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Asthma, a chronic inflammatory disorder of the airways, is coordinated by Th2 cells in both human asthmatics and animal models of allergic asthma. It has been shown that helminth infections including Schistosoma mansoni may modulate atopic diseases including asthma. In the present study, BALB/c mice were infected with bisexual and unisexual (male) S. japonicum, respectively, prior to ovalbumin (OVA) sensitization and challenge. Compared to mice with OVA sensitization/challenge alone, S. japonicum infection led to a significant decrease of eosinophil accumulation in bronchoalveolar lavage fluid (BALF) collected 48 h postchallenge, as well as to a marked reduction in inflammatory cell infiltration around the airways and pulmonary blood vessels. Compared to OVA-immunized uninfected mice, the level of OVA-specific serum IgE as well as interleukin (IL)-4 and IL-5 in BALF were reduced, but IL-10 was strongly elevated in mice with preexisting S. japonicum infection prior to OVA immunization. These results suggest that both bisexual and male S. japonicum infections may modulate the development of allergic asthma. | Can parasite infections by Schistosoma japonicum prevent or improve asthma? | It has been shown that helminth infections including Schistosoma mansoni may modulate atopic diseases including asthma. |
T-cell acute lymphoblastic leukemia (T-ALL) is characterized as a high-risk stratified disease associated with frequent relapse, chemotherapy resistance, and a poorer prognostic outlook than B-precursor ALL. Many of the challenges in treating T-ALL reflect the lack of prognostic cytogenetic or molecular abnormalities on which to base therapy, including targeted therapy. Notch1 activating mutations were identified in more than 50% of T-ALL cases and can be therapeutically targeted with γ-secretase inhibitors (GSIs). Mutant Notch1 can activate cMyc and PI3K-AKT-mTOR1 signaling in T-ALL. In T-ALLs with wild-type phosphatase and tensin homolog deleted on chromosome ten (PTEN), Notch1 transcriptionally represses PTEN, an effect reversible by GSIs. Notch1 also promotes growth factor receptor (IGF1R and IL7Rα) signaling to PI3K-AKT. Loss of PTEN is common in primary T-ALLs due to mutation or posttranslational inactivation and results in chronic activation of PI3K-AKT-mTOR1 signaling, GSI-resistance, and repression of p53-mediated apoptosis. Notch1 itself might regulate posttranslational inactivation of PTEN. PP2A is activated by Notch1 in PTEN-null T-ALL cells, and GSIs reduce PP2A activity and increase phosphorylation of AKT, AMPK, and p70S6K. This review focuses on the central role of the PI3K-AKT-mTOR1 signaling in T-ALL, including its regulation by Notch1 and potential therapeutic interventions, with emphasis on GSI-resistant T-ALL. | Are Notch mutations related to T-cell Acute Lymphoblastic Leukemia (T-ALL)? | T-cell acute lymphoblastic leukemia (T-ALL) is characterized as a high-risk stratified disease associated with frequent relapse, chemotherapy resistance, and a poorer prognostic outlook than B-precursor ALL. Many of the challenges in treating T-ALL reflect the lack of prognostic cytogenetic or molecular abnormalities on which to base therapy, including targeted therapy. Notch1 activating mutations were identified in more than 50% of T-ALL cases and can be therapeutically targeted with γ-secretase inhibitors (GSIs). |
Adaptive (stationary phase) mutagenesis is a phenomenon by which nondividing cells acquire beneficial mutations as a response to stress. Although the generation of adaptive mutations is essentially stochastic, genetic factors are involved in this phenomenon. We examined how defects in a transcriptional factor, previously reported to alter the acquisition of adaptive mutations, affected mutation levels in a gene under selection. The acquisition of mutations was directly correlated to the level of transcription of a defective leuC allele placed under selection. To further examine the correlation between transcription and adaptive mutation, we placed a point-mutated allele, leuC427, under the control of an inducible promoter and assayed the level of reversion to leucine prototrophy under conditions of leucine starvation. Our results demonstrate that the level of Leu(+) reversions increased significantly in parallel with the induced increase in transcription levels. This mutagenic response was not observed under conditions of exponential growth. Since transcription is a ubiquitous biological process, transcription-associated mutagenesis may influence evolutionary processes in all organisms. | Is transcription-associated mutagenesis (TAM) related to gene expression levels? | The acquisition of mutations was directly correlated to the level of transcription |
Atlanto-axial rotatory fixation (AARF) is a rare cause of childhood torticollis that may occur spontaneously or in association with trauma and upper respiratory infections. We describe the clinical findings, as well as the effectiveness of imaging in the diagnosis and the treatment of 4 children with AARF, in whom acute fixed non-dystonic torticollis was the presenting symptom. Onset of torticollis was spontaneous in Case 1, after general anesthesia for cholesteatoma surgery in Case 2, after a trauma in Case 3, and during hypersomnia in Case 4. Duration of torticollis prior to diagnosis was 3 months in the first two patients and 20 days in the other two. All the patients underwent cervical X-rays examinations, which were not contributory to the diagnosis, followed by CT, which demonstrated C1-C2 rotatory fixation. One patient had a spontaneous resolution; treatment with Gardner's tongs and soft collar permitted restoration of the normal alignment in the other 3 patients. AARF must be considered in all the patients with persistent painful torticollis. | Atlanto-axial rotary instability (Fielding type 1) is common to what diseases? | Atlanto-axial rotatory fixation (AARF) is a rare cause of childhood torticollis that may occur spontaneously or in association with trauma and upper respiratory infections. |
Patau syndrome is a chromosomal disorder associated with multiple malformations caused by inheritance of an extra chromosome (trisomy 13). Some skin defects have been reported in patients with Patau syndrome, such as scalp defects, glabellar stains, deep palmar creases, rocker-bottom feet, convex soles, hyperconvextity of the nails, and multiple hemangiomas. To our knowledge, widespread comedonal and cystic acne have not been previously reported in Patau syndrome. | Which is the main cause of the Patau syndrome? | Patau syndrome is a chromosomal disorder associated with multiple malformations caused by inheritance of an extra chromosome (trisomy 13). |
In 2 large, randomized, double-masked trials reported here, once-daily dosing of netarsudil 0.02% was found to be effective and well tolerated for the treatment of patients with ocular hypertension and open-angle glaucoma. The novel pharmacology and aqueous humor dynamic effects of this molecule suggest it may be a useful addition to the armamentarium of ocular hypotensive medications. | Which diseases are treated with netarsudil? | In 2 large, randomized, double-masked trials reported here, once-daily dosing of netarsudil 0.02% was found to be effective and well tolerated for the treatment of patients with ocular hypertension and open-angle glaucoma. |
Non-alcoholic fatty liver disease (NAFLD) has become one of the most prominent forms of chronic liver disease worldwide, reflecting the epidemic of global obesity. Those with the progressive variant of NAFLD, non-alcoholic steatohepatitis (NASH), are at significantly increased risk of multisystem morbidity and mortality. However, there are currently no approved pharmacologic therapies for NASH. Given the disease burden, there is an important unmet need for pharmacologic treatment options for this patient population. The underlying pathophysiologic mechanisms that contribute to the development and progression of NAFLD and NASH are complex and reflected by the myriad of therapies, with different targets, currently under investigation. In broad strokes, drug development has focused on modulation of metabolic pathways, inflammatory cascades, and/or mechanisms impacting fibrosis. Although much progress has been made in enhancing our understanding of NAFLD pathogenesis, development of pharmacologic treatments has been hindered by challenges in clinical trial enrollment and complexities in clinical trial design. The compounds in phase IIa have provided promising results in terms of potential benefits on various aspects of histopathology. Agents in later stages of development have shown fairly modest results in terms of reduction of hepatic steatosis, necroinflammation and fibrosis. If longer term safety and efficacy are established among heterogeneous cohorts, these medications may help mitigate potential morbidity and mortality for this burgeoning patient population. | Is there any approved treatment for NAFLD? | Non-alcoholic fatty liver disease (NAFLD) has become one of the most prominent forms of chronic liver disease worldwide, reflecting the epidemic of global obesity. Those with the progressive variant of NAFLD, non-alcoholic steatohepatitis (NASH), are at significantly increased risk of multisystem morbidity and mortality. However, there are currently no approved pharmacologic therapies for NASH. |
Thirty-two children with refractory partial epilepsy received open-label gabapentin as an additional medication to their antiepileptic drug regimen. Gabapentin was given in a dose ranging from 10 to 50 mg/kg per day (mean dose, 26.7 mg/kg daily). All patients had partial seizures with or without secondary generalization. Compared with baseline, 11 patients (34.4%) had a greater than 50% decrease in seizure frequency, and 4 (12.5%) had a 25% to 50% decrease in seizure frequency. Of the seven children who received the medication for 6 months or longer, two were seizure free and four were almost seizure free (having one seizure every few months). Mean gabapentin concentration was 4.8 micrograms/ml, and mean apparent clearance was 372 ml/kg per hour. The major reported side effects were behavioral. These consisted of hyperactivity, irritability, and agitation that occurred in patients with baseline mental retardation with attention deficit. We conclude that gabapentin can be a useful adjunctive medication in the treatment of refractory partial epilepsy in children. | What are the reported adverse effects of gabapentin used in children? | The major reported side effects were behavioral. These consisted of hyperactivity, irritability, and agitation that occurred in patients with baseline mental retardation with attention deficit. |
A Chinese family affected with autosomal dominant disorder-neurofibromatosis type I was identified in this study. Linkage analysis was performed, and DNA sequencing for whole coding region of NF1 was carried out to identify the disease-causing mutation. The disease gene of the Chinese NF1 family was linked to NF1 locus, and a nonsense mutation, G1336X in the NF1 gene was identified. This mutation truncates the NF1 protein by 1 483 amino acid residues at the C-terminus, and is co-segregate with all the patients, but not present in unaffected individuals in the family. The present study demonstrated that G1336X mutation in the NF1 gene cause Neurofibromatosis type I in the family. To our knowledge, this mutation is firstly reported in Chinese population. | Mutation of which gene and which chromosome cause Neurofibromatosis type I? | The present study demonstrated that G1336X mutation in the NF1 gene cause Neurofibromatosis type I in the family. |
Aberrant expression of microRNAs (miRNAs) plays important roles in carcinogenesis and tumor progression. However, the expression and biological role of miR-301b in triple-negative breast cancer (TNBC) remains unclear. Here we aimed to evaluate the roles and mechanisms of miR-301b in TNBC cells. miR-301b expression was assessed in TNBC specimens and cell lines by quantitative Real-Time PCR (qRT-PCR). TNBC cells were transfected with miR-301b mimics, inhibitors or Cylindromatosis (CYLD) small interfering RNA (siRNA) using Lipofectamine 2000. The functional roles of miR-301b were determined by cell proliferation, colony formation, and apoptosis assays. Western blots and qRT-PCR were used to measure the expression of mRNAs and proteins in the cells. We found that miR-301b was upregulated in TNBC specimens and cell lines. Overexpression of miR-301b promoted cell proliferation in TNBC cells, while inhibited the apoptosis induced by 5-FU. CYLD was downregulated by miR-301b at both mRNA and protein levels in TNBC cells. Dual-luciferase report assay confirmed that miR-301b downregulated CYLD by direct interaction with the 3'-untranslated region(3'-UTR) of CYLD mRNA. NF-κB activation was mechanistically associated with miR-301b-mediated downregulation of CYLD. However, inhibition of miR-301b reversed all the effects of miR-301b. In conclusion, miR-301b plays an oncogenic role in TNBC possibly by downregulating CYLD and subsequently activating NF-κB p65, and this may provide a novel therapeutic approach for TNBC. [BMB Reports 2018; 51(11): 602-607]. | Which microRNAs are involved in targeting CYLD in triple negative breast cancer? | Aberrant expression of microRNAs (miRNAs) plays important roles in carcinogenesis and tumor progression. However, the expression and biological role of miR-301b in triple-negative breast cancer (TNBC) remains unclear. Here we aimed to evaluate the roles and mechanisms of miR-301b in TNBC cells. miR-301b expression was assessed in TNBC specimens and cell lines by quantitative Real-Time PCR (qRT-PCR). TNBC cells were transfected with miR-301b mimics, inhibitors or Cylindromatosis (CYLD) small interfering RNA (siRNA) using Lipofectamine 2000. The functional roles of miR-301b were determined by cell proliferation, colony formation, and apoptosis assays. Western blots and qRT-PCR were used to measure the expression of mRNAs and proteins in the cells. We found that miR-301b was upregulated in TNBC specimens and cell lines. Overexpression of miR-301b promoted cell proliferation in TNBC cells, while inhibited the apoptosis induced by 5-FU. CYLD was downregulated by miR-301b at both mRNA and protein levels in TNBC cells. Dual-luciferase report assay confirmed that miR-301b downregulated CYLD by direct interaction with the 3'-untranslated region(3'-UTR) of CYLD mRNA. NF-κB activation was mechanistically associated with miR-301b-mediated downregulation of CYLD. However, inhibition of miR-301b reversed all the effects of miR-301b. In conclusion, miR-301b plays an oncogenic role in TNBC possibly by downregulating CYLD and subsequently activating NF-κB p65, and this may provide a novel therapeutic approach for TNBC. |
REPAIRtoire is the first comprehensive database resource for systems biology of DNA damage and repair. The database collects and organizes the following types of information: (i) DNA damage linked to environmental mutagenic and cytotoxic agents, (ii) pathways comprising individual processes and enzymatic reactions involved in the removal of damage, (iii) proteins participating in DNA repair and (iv) diseases correlated with mutations in genes encoding DNA repair proteins. REPAIRtoire provides also links to publications and external databases. REPAIRtoire contains information about eight main DNA damage checkpoint, repair and tolerance pathways: DNA damage signaling, direct reversal repair, base excision repair, nucleotide excision repair, mismatch repair, homologous recombination repair, nonhomologous end-joining and translesion synthesis. The pathway/protein dataset is currently limited to three model organisms: Escherichia coli, Saccharomyces cerevisiae and Homo sapiens. The DNA repair and tolerance pathways are represented as graphs and in tabular form with descriptions of each repair step and corresponding proteins, and individual entries are cross-referenced to supporting literature and primary databases. REPAIRtoire can be queried by the name of pathway, protein, enzymatic complex, damage and disease. In addition, a tool for drawing custom DNA-protein complexes is available online. REPAIRtoire is freely available and can be accessed at http://repairtoire.genesilico.pl/. | What is the content of the REPAIRtoire database? | The database collects and organizes the following types of information: (i) DNA damage linked to environmental mutagenic and cytotoxic agents, (ii) pathways comprising individual processes and enzymatic reactions involved in the removal of damage, (iii) proteins participating in DNA repair and (iv) diseases correlated with mutations in genes encoding DNA repair proteins. REPAIRtoire provides also links to publications and external databases. |
An overexpression of the transmembrane ATP-binding cassette transporter G2 (ABCG2, BCRP) in cancer tissues is supposed to play a role in the multidrug resistance (MDR) of tumors resulting in an inefficient chemotherapy. Therefore, co-administration of selective and non-toxic ABCG2 inhibitors is a promising strategy for improving the efficacy of chemotherapy by blocking ABCG2-mediated export of the cytostatic drugs. In the present study, we designed a small library of 38 novel compounds containing a heteroaryl-phenyl scaffold possessing several (bioisosteric) moieties, and twelve new precursors. We investigated the library for ABCG2 inhibition, for the selectivity against MDR-involved efflux pump ABCB1 (P-gp) and for toxicity. Structure activity relationship (SAR) studies revealed that, at least a phenylheteroaryl-phenylamide scaffold is necessary for observing an ABCG2 inhibition. 4-Methoxy-N-(2-(2-(6-methoxypyridin-3-yl)-2H-tetrazol-5-yl)phenyl)benzamide (43) exhibited a high potency (IC = 61 nM)), selectivity, low intrinsic toxicity and reversed the ABCG2-mediated drug resistance in presence of only 0.1 μM. | Is the protein ABCG2 transmembrane? | the transmembrane ATP-binding cassette transporter G2 |
The authors present a 21-year-old woman who has been receiving rapamycin for 5 months for bilateral subependymal giant cell astrocytomas. The patient was started at a dose of 0.2 mg/kg/day. Levels were maintained between 11 and 13 ng/mL. Magnetic resonance imaging of the brain 2(1/2) months after initiating rapamycin demonstrated a decrease in size of both astrocytomas (11 to 7.5 mm on the right and 8 to 5 mm on the left). Further studies are needed with prolonged observation to confirm these findings, determine the length of necessary treatment, and evaluate recurrence risk after discontinuation of rapamycin. | List two chemotherapeutic agents that are used for treatment of Subependymal Giant Cell Astrocytoma | The authors present a 21-year-old woman who has been receiving rapamycin for 5 months for bilateral subependymal giant cell astrocytomas. |
Cystic fibrosis (CF) was considered to be non-existent in Indian subcontinent. Reports in last one decade have suggested that cystic fibrosis occurs in India but its precise magnitude is not known. Studies on migrant Indian population in United States and United Kingdom estimate frequency of CF as 1:10,000 to 1:40,000. The clinical features are similar to that reported in Caucasian population. CF in Indian children is usually diagnosed late and in advanced stage. Children are more malnourished and may have clinically evident deficiency of fat soluble vitamins. The frequency of clubbing, colonization with Pseudomonas, and laboratory evidence of pseudo-Bartter syndrome is relatively more at the time of diagnosis. Diagnostic facilities in form of sweat chloride estimation and genetic studies are not available readily. Mutation profile is different. The frequency of common mutation F508del in Indian children is between 19% and 34%. Other mutations are heterogeneous. Management of CF in India is difficult due to less number of trained manpower, limited availability, and high cost of pharmacologic agents. The determinants of early death include: severe malnutrition and colonization with Pseudomonas at the time of diagnosis, more than four episodes of lower respiratory infection per year and age of onset of symptoms before 2 months of age. To conclude, CF does occur in India; however, precise magnitude of problem is not known. There is need to create awareness amongst pediatricians, developing diagnostic facilities, and management protocols based on locally available resources. | What is the incidence of cystic fibrosis in the caucasian population? | Studies on migrant Indian population in United States and United Kingdom estimate frequency of CF as 1:10,000 to 1:40,000 |
Arrhythmias can develop in various cardiac diseases, such as ischemic heart disease, cardiomyopathy and congenital heart disease. It can also contribute to the aggravation of heart failure and sudden cardiac death. Redox stress and Ca(2+) overload are thought to be the important triggering factors in the generation of arrhythmias in failing myocardium. From recent studies, it appears evident that Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) plays a central role in the arrhythmogenic processes in heart failure by sensing intracellular Ca(2+) and redox stress, affecting individual ion channels and thereby leading to electrical instability in the heart. CaMKII, a multifunctional serine/threonine kinase, is an abundant molecule in the neuron and the heart. It has a specific property as "a memory molecule" such that the binding of calcified calmodulin (Ca(2+)/CaM) to the regulatory domain on CaMKII initially activates this enzyme. Further, it allows autophosphorylation of T287 or oxidation of M281/282 in the regulatory domain, resulting in sustained activation of CaMKII even after the dissociation of Ca(2+)/CaM. This review provides the understanding of both the structural and functional properties of CaMKII, the experimental findings of the interactions between CaMKII, redox stress and individual ion channels, and the evidences proving the potential participation of CaMKII and oxidative stress in the diverse arrhythmogenic processes in a diseased heart. | Is Calcium/Calmodulin dependent protein kinase II (CaMKII) involved in cardiac arrhythmias and heart failure? | From recent studies, it appears evident that Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) plays a central role in the arrhythmogenic processes in heart failure by sensing intracellular Ca(2+) and redox stress, affecting individual ion channels and thereby leading to electrical instability in the heart. |
Genital herpes is the most prevalent sexually transmitted infection in the USA. While sometimes mild in severity, it can be a distressing and painful chronic condition. Likewise, herpes labialis and herpes zoster can be both physically and psychologically painful. While there is no cure for these conditions, treatment to alleviate symptoms, suppress recurrences and reduce transmission has been drastically improved over the past 20 years with the use of guanine nucleoside antivirals, such as valacyclovir hydrochloride (Valtrex), GlaxoSmithKline) the highly bioavailable prodrug of acyclovir (Zovirax((R)), GlaxoSmithKline), and famciclovir (Famvir, Novartis), a highly bioavailable prodrug of penciclovir (Denavir, Novartis). Clinical trials involving approximately 10,000 patients (including patients from nongenital herpes studies, such as herpes zoster) have assessed the safety and efficacy of valacyclovir in the treatment of initial genital herpes outbreaks, episodic treatment of recurrent episodes and daily suppressive therapy. It was shown that valacyclovir has similar efficacy to acyclovir in the episodic and suppressive treatment of genital herpes. Valacyclovir is the only antiviral drug approved for a once-daily dose of suppressive therapy for genital herpes, as well as the only antiviral drug US FDA approved for a 3-day regimen of episodic treatment of recurrent genital herpes. In addition, valacyclovir is also indicated in the reduction of the sexual transmission of herpes simplex virus infection and for the treatment of herpes labialis. In herpes zoster, valacyclovir is more effective than acyclovir or placebo (and as equally effective as famciclovir) in shortening the length and severity of herpes zoster-associated pain and postherpetic neuralgia. Valacyclovir has an acceptable safety profile in patients with herpes simplex and herpes zoster. The less frequent dosing regimen makes it an attractive option in the treatment of genital herpes and other viral infections, and may contribute to increased patient adherence to therapy. | Please list 3 diseases treated with Valtrex(valacyclovir) | n herpes zoster, valacyclovir is more effective than acyclovir or placebo (and as equally effective as famciclovir) in shortening the length and severity of herpes zoster-associated pain and postherpetic neuralgia. |
Calcification, fibrosis, and chronic inflammation are the predominant features of calcific aortic valve disease, a life-threatening condition. Drugs that induce serotonin (5-hydroxytryptamine [5-HT]) are known to damage valves, and activated platelets, which carry peripheral serotonin, are known to promote calcific aortic valve stenosis. However, the role of 5-HT in valve leaflet pathology is not known. We tested whether serotonin mediates inflammation-induced matrix mineralization in valve cells. Real-time reverse transcription-polymerase chain reaction analysis showed that murine aortic valve interstitial cells (VICs) expressed both serotonin receptor types 2A and 2B (Htr2a and Htr2b). Although Htr2a expression was greater at baseline, Htr2b expression was induced several-fold more than Htr2a in response to the pro-calcific tumor necrosis factor-α (TNF-α) treatment. 5-HT also augmented TNF-α-induced osteoblastic differentiation and matrix mineralization of VIC, but 5-HT alone had no effects. Inhibition of serotonin receptor type 2B, using specific inhibitors or lentiviral knockdown in VIC, attenuated 5-HT effects on TNF-α-induced osteoblastic differentiation and mineralization. 5-HT treatment also augmented TNF-α-induced matrix metalloproteinase-3 expression, which was also attenuated by Htr2b knockdown. Htr2b expression in aortic roots and serum levels of peripheral 5-HT were also greater in the hyperlipidemic Apoe mice than in control normolipemic mice. These findings suggest a new role for serotonin signaling in inflammation-induced calcific valvulopathy. | Is serotonin transported by platelets? | activated platelets, which carry peripheral serotonin, |
We present a simple, time- and cost-efficient approach to tackle the proteome of prokaryotic organisms. To obtain large data sets of complex biological experiments high-throughput and time- and cost-efficient methods still have to be developed and refined. In this study, we combined well-approved techniques, namely elevated chromatographic temperatures, long RP columns and the multidimensional protein identification technology MudPIT to achieve high proteome coverage. The advanced MudPIT approach has been evaluated and delivered very comprehensive results for Gram-positive as well as Gram-negative bacteria (53% proteome coverage for Corynebacterium glutamicum and 46% proteome coverage for Escherichia coli). Also, a high identification rate for the challenging integral membrane proteins was achieved. The competitiveness of the advanced MudPIT technology is strengthened by the fact that in this approach only two fractions were analyzed with both, simple and time-efficient sample preparation, and a moderate data acquisition time. | What is the advantage of using long nano columns in proteomics? | Also, a high identification rate for the challenging integral membrane proteins was achieved. |
Inherited and acquired changes in DNA can influence the coding for gene products (proteins). When the function of a protein is disturbed, this may lead to disease. DNA in chromatin can be condensed or be arranged in an open structure. The activity of genes is significantly affected by the accessibility to DNA by transcription factors and other proteins involved in the transcription of genes. The accessibility of DNA is regulated by epigenetic processes, including methylation of cytosine. In these circumstances the nucleic sequence of the DNA does not change. Nevertheless, disturbances of these processes can also culminate in disease. Epigenetic changes to DNA are reversible. This offers opportunities for treatment and recovery in conditions that are a result of disturbed epigenetic processes. | Do epigenetic changes change the DNA sequence? | The accessibility of DNA is regulated by epigenetic processes, including methylation of cytosine. In these circumstances the nucleic sequence of the DNA does not change. |
During 'emergency' situations such as infections, host defense requires rapid mobilization of bone marrow granulocyte progenitors. 'Steady-state' granulopoiesis is absolutely dependent on the C/EBPalpha transcription factor, but the transcriptional mechanisms underlying emergency granulopoiesis remain unclear. Here we show that large numbers of granulocytes were generated from C/EBPalpha-deficient progenitors after cytokine stimulation in vivo. Cytokine treatment or fungal infection induced upregulation of C/EBPbeta but not C/EBPalpha or C/EBPepsilon transcripts in granulocyte progenitors, and C/EBPbeta-deficient progenitors showed decreased emergency-induced granulopoiesis in vitro and in vivo. C/EBPbeta inhibited proliferation less severely than did C/EBPalpha. These data suggest a critical function for C/EBPbeta in emergency granulopoiesis, which demands both differentiation and proliferation of granulocyte precursors. | Which transcription factor regulates emergency granulopoiesis? | Cytokine treatment or fungal infection induced upregulation of C/EBPbeta but not C/EBPalpha or C/EBPepsilon transcripts in granulocyte progenitors, and C/EBPbeta-deficient progenitors showed decreased emergency-induced granulopoiesis in vitro and in vivo. |
Relatively little is known about programmed cell death (PCD) in plants. It is nonetheless suggested here that tonoplast rupture and the subsequent rapid destruction of the cytoplasm can distinguish two large PCD classes. One class, which is here called 'autolytic', shows this feature, whilst the second class (called 'non-autolytic') can include tonoplast rupture but does not show the rapid cytoplasm clearance. Examples of the 'autolytic' PCD class mainly occur during normal plant development and after mild abiotic stress. The 'non-autolytic' PCD class is mainly found during PCD that is due to plant-pathogen interactions. Three categories of PCD are currently recognized in animals: apoptosis, autophagy, and necrosis. An attempt is made to reconcile the recognized plant PCD classes with these groups. Apoptosis is apparently absent in plants. Autophagic PCD in animals is defined as being accompanied by an increase in the number of autophagosomes, autolysosomes, and small lytic vacuoles produced by autolysosomes. When very strictly adhering to this definition, there is no (proof for) autophagic PCD in plants. Upon a slightly more lenient definition, however, the 'autolytic' class of plant PCD can be merged with the autophagic PCD type in animal cells. The 'non-autolytic' class of plant PCD, as defined here, can be merged with necrotic PCD in animals. | What is the definition of autophagy? | Autophagic PCD in animals is defined as being accompanied by an increase in the number of autophagosomes, autolysosomes, and small lytic vacuoles produced by autolysosomes |
Devic's neuromyelitis optica is a rare syndrome characterised by the combination of acute or subacute optic neuritis and transverse myelitis, in some cases considered to be a variant of multiple sclerosis. Mutations of mitochondrial DNA (mtDNA) associated with Leber hereditary optic neuropathy (LHON) have been identified in some patients with multiple sclerosis in whom optic neuritis is a prominent early feature. Using restriction enzyme digestion of mtDNA products amplified by the polymerase chain reaction, the primary LHON mtDNA mutations at positions 3460 bp, 11,778 bp, and 14,484 bp have been excluded in four women with Devic's neuromyelitis optica. A mutation at 4160 bp associated in some LHON families with more widespread neurological disease was also not detected. It is concluded that the primary mtDNA mutations currently associated with LHON are not responsible for the prominence of optic nerve disease in Devic's neuromyelitis optica. | What is LHON, also known as Lebers syndrome? | Leber hereditary optic neuropathy (LHON) |
Ingestion of soapberry fruit toxins hypoglycin A and methylenecyclopropylglycine has been linked to public health challenges worldwide. In 1976, over 100 years after Jamaican vomiting sickness (JVS) was first reported, the cause of JVS was linked to the ingestion of the toxin hypoglycin A produced by ackee fruit. A structural analogue of hypoglycin A, methylenecyclopropylglycine (MCPG), was implicated as the cause of an acute encephalitis syndrome (AES). Much of the evidence linking hypoglycin A and MCPG to these diseases has been largely circumstantial due to the lack of an analytical method for specific metabolites. This study presents an analytical approach to identify and quantify specific urine metabolites for exposure to hypoglycin A and MCPG. The metabolites are excreted in urine as glycine adducts methylenecyclopropylacetyl-glycine (MCPA-Gly) and methylenecyclopropylformyl-glycine (MCPF-Gly). These metabolites were processed by isotope dilution, separated by reverse-phase liquid chromatography, and monitored by electrospray ionization tandem mass spectrometry. The analytical response ratio was linearly proportional to the concentration of MCPF-Gly and MCPA-Gly in urine from 0.10 to 20 μg/mL with a correlation coefficient of r > 0.99. The assay demonstrated accuracy ≥80% and precision ≤20% RSD across the calibration range. This method has been applied to assess exposure to hypoglycin A and MCPG as part of a larger public health initiative and was used to provide the first reported identification of MCPF-Gly and MCPA-Gly in human urine. | What fruit causes Jamaican vomiting sickness? | In 1976, over 100 years after Jamaican vomiting sickness (JVS) was first reported, the cause of JVS was linked to the ingestion of the toxin hypoglycin A produced by ackee fruit. |
Guanidino compounds (GCs), such as creatine, phosphocreatine, guanidinoacetic acid, creatinine, methylguanidine, guanidinosuccinic acid, γ-guanidinobutyric acid, β-guanidinopropionic acid, guanidinoethane sulfonic acid and α-guanidinoglutaric acid, are present in the mammalian brain. Although creatine and phosphocreatine play important roles in energy homeostasis in the brain, accumulation of GCs may induce epileptic discharges and convulsions. This review focuses on how physiologically important and/or neurotoxic GCs are distributed in the brain under physiological and pathological conditions. Transporters for GCs at the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (BCSFB) have emerged as substantial contributors to GCs distribution in the brain. Creatine transporter (CRT/solute carrier (SLC) 6A8) expressed at the BBB regulates creatine concentration in the brain, and represents a major pathway for supply of creatine from the circulating blood to the brain. CRT may be a key factor facilitating blood-to-brain guanidinoacetate transport in patients deficient in S-adenosylmethionine:guanidinoacetate N-methyltransferase, the creatine biosynthetic enzyme, resulting in cerebral accumulation of guanidinoacetate. CRT, taurine transporter (TauT/SLC6A6) and organic cation transporter (OCT3/SLC22A3) expressed at the BCSFB are involved in guanidinoacetic acid or creatinine efflux transport from CSF. Interestingly, BBB efflux transport of GCs, including guanidinoacetate and creatinine, is negligible, though the BBB has a variety of efflux transport systems for synthetic precursors of GCs, such as amino acids and neurotransmitters. Instead, the BCSFB functions as a major cerebral clearance system for GCs. In conclusion, transport of GCs at the BBB and BCSFB appears to be the key determinant of the cerebral levels of GCs, and changes in the transport characteristics may cause the abnormal distribution of GCs in the brain seen in patients with certain neurological disorders. | Is SLC22A3 expressed in the brain? | CRT, taurine transporter (TauT/SLC6A6) and organic cation transporter (OCT3/SLC22A3) expressed at the BCSFB are involved in guanidinoacetic acid or creatinine efflux transport from CSF. |
X-Linked Emery-Dreifuss muscular dystrophy is caused by mutations in the gene encoding emerin. Emerin is an inner nuclear membrane protein important for repressive chromatin organization at the nuclear periphery. Myogenic differentiation is a tightly regulated process characterized by genomic reorganization leading to coordinated temporal expression of key transcription factors, including MyoD, Pax7, and Myf5. Emerin was shown to interact with repressive histone modification machinery, including HDAC3 and EZH2. Using emerin-null myogenic progenitor cells we established several EDMD-causing emerin mutant lines in the effort to understand how the functional interaction of emerin with HDAC3 regulates histone methyltransferase localization or function to organize repressive chromatin at the nuclear periphery. We found that, in addition to its interaction with HDAC3, emerin interacts with the histone methyltransferases EZH2 and G9a in myogenic progenitor cells. Further, we show enhanced binding of emerin HDAC3-binding mutants S54F and Q133H to EZH2 and G9a. Treatment with small molecule inhibitors of EZH2 and G9a reduced H3K9me2 or H3K27me3 throughout differentiation. EZH2 and G9a inhibitors impaired cell cycle withdrawal, differentiation commitment, and myotube formation in wildtype progenitors, while they had no effect on emerin-null progenitors. Interestingly, these inhibitors exacerbated the impaired differentiation of emerin S54F and Q133H mutant progenitors. Collectively, these results suggest the functional interaction between emerin and HDAC3, EZH2, and G9a are important for myogenic differentiation. | What is Emery-Dreifuss Muscular Dystrophy (EDMD)? | X-Linked Emery-Dreifuss muscular dystrophy is caused by mutations in the gene encoding emerin. |
mRNA? | With this step, a pre-messenger RNA is processed and polyadenylated, giving rise to a mature mRNA bearing the characteristic poly(A) tract. | null |
Hirschsprung disease (HSCR, OMIM 142623) is a developmental disorder characterized by the absence of ganglion cells along variable lengths of the distal gastrointestinal tract, which results in tonic contraction of the aganglionic gut segment and functional intestinal obstruction. The RET proto-oncogene is the major gene for HSCR with differential contributions of its rare and common, coding and noncoding mutations to the multifactorial nature of this pathology. Many other genes have been described to be associated with the pathology, as NRG1 gene (8p12), encoding neuregulin 1, which is implicated in the development of the enteric nervous system (ENS), and seems to contribute by both common and rare variants. Here we present the results of a comprehensive analysis of the NRG1 gene in the context of the disease in a series of 207 Spanish HSCR patients, by both mutational screening of its coding sequence and evaluation of 3 common tag SNPs as low penetrance susceptibility factors, finding some potentially damaging variants which we have functionally characterized. All of them were found to be associated with a significant reduction of the normal NRG1 protein levels. The fact that those mutations analyzed alter NRG1 protein would suggest that they would be related with HSCR disease not only in Chinese but also in a Caucasian population, which reinforces the implication of NRG1 gene in this pathology. | Is RET the major gene involved in Hirschsprung disease? | The RET proto-oncogene is the major gene for HSCR with differential contributions of its rare and common, coding and noncoding mutations to the multifactorial nature of this pathology |
We now recognize that not all breast cancers are the same. Different characteristics in gene expression profiles result in differential clinical behavior. With the use of gene microarrays, different subtypes of breast cancer have been characterized. These subtypes include the basal, the ERBB2+, and the luminal A, B and C subtypes. The importance of these different subtypes lies in the fact that they differ in clinical outcome, with the basal and ERBB2+ subtypes having the worst prognosis and the luminal A group having the best prognosis. However, identification of these subtypes is still not clinically used. Other strategies for evaluating tumors in a clinical setting have been developed using smaller sets of genes. One such strategy is the 21-gene assay (Oncotype DX), which is currently in commercial use in the USA. One advantage of this test is the use of paraffin-embedded blocks instead of previous methods, which required fresh frozen tissue. Oncotype DX has been shown to predict 10-year distant recurrence in patients with estrogen receptor-positive, axillary lymph node-negative breast cancer. This genomic assay has also been shown to predict chemotherapy and endocrine therapy response. Large, prospective, randomized clinical trials are currently underway using this genomic test. Other similar tests are also finding their way in clinical practice. A 70-gene assay, which has been developed by a group in The Netherlands, is currently being used as a tool to assign treatment in women with early stage breast cancer. In the near future, clinical decisions will most likely be dictated by the genetic characteristics of the tumor, with the clinical characteristics becoming less important. Tailoring our treatment based on individual tumor characteristics will help us develop better therapeutic strategies and save many of our patients from receiving unnecessary toxic therapy. | Does the Oncotype DX test work with paraffin embedded tissues? | One such strategy is the 21-gene assay (Oncotype DX), which is currently in commercial use in the USA. One advantage of this test is the use of paraffin-embedded blocks instead of previous methods, which required fresh frozen tissue. |
Although it is debated whether chronic cerebro-spinal venous insufficiency (CCSVI) plays a role in multiple sclerosis (MS) development, many patients undergo endovascular treatment (ET) of CCSVI. A study is ongoing in Italy to evaluate the clinical outcome of ET. Severe adverse events (AEs) occurred in 15/462 subjects at a variable interval after ET: jugular thrombosis in seven patients, tetraventricular hydrocephalus, stroke, paroxysmal atrial fibrillation, status epilepticus, aspiration pneumonia, hypertension with tachicardia, or bleeding of bedsore in the remaining seven cases. One patient died because of myocardial infarction 10 weeks after ET. The risk of severe AEs related to ET for CCSVI must be carefully considered. | What is the lay name of the treatment for CCSVI (chronic cerebro-spinal venous insufficiency) in multiple sclerosis. | Although it is debated whether chronic cerebro-spinal venous insufficiency (CCSVI) plays a role in multiple sclerosis (MS) development, many patients undergo endovascular treatment (ET) of CCSVI |
Regulatory sequences recognized by the unique pair of paralogous factors, CTCF and BORIS, have been implicated in epigenetic regulation of imprinting and X chromosome inactivation. Lung cancers exhibit genome-wide demethylation associated with derepression of a specific class of genes encoding cancer-testis (CT) antigens such as NY-ESO-1. CT genes are normally expressed in BORIS-positive male germ cells deficient in CTCF and meCpG contents, but are strictly silenced in somatic cells. The present study was undertaken to ascertain if aberrant activation of BORIS contributes to derepression of NY-ESO-1 during pulmonary carcinogenesis. Preliminary experiments indicated that NY-ESO-1 expression coincided with derepression of BORIS in cultured lung cancer cells. Quantitative reverse transcription-PCR analysis revealed robust, coincident induction of BORIS and NY-ESO-1 expression in lung cancer cells, but not normal human bronchial epithelial cells following 5-aza-2'-deoxycytidine (5-azadC), Depsipeptide FK228 (DP), or sequential 5-azadC/DP exposure under clinically relevant conditions. Bisulfite sequencing, methylation-specific PCR, and chromatin immunoprecipitation (ChIP) experiments showed that induction of BORIS coincided with direct modulation of chromatin structure within a CpG island in the 5'-flanking noncoding region of this gene. Cotransfection experiments using promoter-reporter constructs confirmed that BORIS modulates NY-ESO-1 expression in lung cancer cells. Gel shift and ChIP experiments revealed a novel CTCF/BORIS-binding site in the NY-ESO-1 promoter, which unlike such sites in the H19-imprinting control region and X chromosome, is insensitive to CpG methylation in vitro. In vivo occupancy of this site by CTCF was associated with silencing of the NY-ESO-1 promoter, whereas switching from CTCF to BORIS occupancy coincided with derepression of NY-ESO-1. Collectively, these data indicate that reciprocal binding of CTCF and BORIS to the NY-ESO-1 promoter mediates epigenetic regulation of this CT gene in lung cancer cells, and suggest that induction of BORIS may be a novel strategy to augment immunogenicity of pulmonary carcinomas. | Are CTCF and BORIS involved in genome regulation and cancer? | Collectively, these data indicate that reciprocal binding of CTCF and BORIS to the NY-ESO-1 promoter mediates epigenetic regulation of this CT gene in lung cancer cells, and suggest that induction of BORIS may be a novel strategy to augment immunogenicity of pulmonary carcinomas. |
Mutation of EMD can underlie X-linked familial AF. Lys37del is associated with epithelial cell emerin deficiency, as in EDMD, yet it causes electrical atriomyopathy in the absence of skeletal muscle disease. Targeted genetic testing of EMD should be considered in patients with SND-associated AF and/or family history suggesting X-linked inheritance. | What is the inheritance pattern of Emery-Dreifuss muscular dystrophy? | Mutation of EMD can underlie X-linked familial AF. Lys37del is associated with epithelial cell emerin deficiency, as in EDMD, yet it causes electrical atriomyopathy in the absence of skeletal muscle disease. Targeted genetic testing of EMD should be considered in patients with SND-associated AF and/or family history suggesting X-linked inheritance. |
Multiple loss-of-function (LOF) alleles at the same gene may influence a phenotype not only in the homozygote state when alleles are considered individually, but also in the compound heterozygote (CH) state. Such LOF alleles typically have low frequencies and moderate to large effects. Detecting such variants is of interest to the genetics community, and relevant statistical methods for detecting and quantifying their effects are sorely needed. We present a collapsed double heterozygosity (CDH) test to detect the presence of multiple LOF alleles at a gene. When causal SNPs are available, which may be the case in next generation genome sequencing studies, this CDH test has overwhelmingly higher power than single SNP analysis. When causal SNPs are not directly available such as in current GWA settings, we show the CDH test has higher power than standard single SNP analysis if tagging SNPs are in linkage disequilibrium with the underlying causal SNPs to at least a moderate degree (r²>0.1). The test is implemented for genome-wide analysis in the publically available software package GenABEL which is based on a sliding window approach. We provide the proof of principle by conducting a genome-wide CDH analysis of red hair color, a trait known to be influenced by multiple loss-of-function alleles, in a total of 7,732 Dutch individuals with hair color ascertained. The association signals at the MC1R gene locus from CDH were uniformly more significant than traditional GWA analyses (the most significant P for CDH = 3.11×10⁻¹⁴² vs. P for rs258322 = 1.33×10⁻⁶⁶). The CDH test will contribute towards finding rare LOF variants in GWAS and sequencing studies. | Which gene is responsible for red hair? | The association signals at the MC1R gene locus from CDH were uniformly more significant than traditional GWA analyses (the most significant P for CDH = 3.11×10⁻¹⁴² vs. P for rs258322 = 1.33×10⁻⁶⁶). The CDH test will contribute towards finding rare LOF variants in GWAS and sequencing studies. |
Intracranial complications of paranasal sinusitis have become rare due to the use of antibiotics nowadays. However, several cases have been reported due the ability of paranasal sinusitis to cause serious complications. Once the infection spreads over the cranial structure, it could infect the orbits, underlying bones, meninges, adjacent veins, and brain. Subdural empyema is a rare but potentially life-threatening complication following paranasal sinusitis and should be considered as a neurological emergency. The location where subdural empyema may appear is a challenge in diagnosis and treatment. We report the case of a 17-year-old boy who presented in a state of somnolence due to interhemispheric and infratentorial subdural empyema with preseptal cellulitis secondary to pansinusitis. Early diagnosis and aggressive antibiotic treatment combined with neurosurgical operation were mandatorily implemented. The case was managed using a multidisciplinary approach including the ENT, eye, and nutrition departments. The boy achieved clinical improvement, with impairment of eye movement as the only persistent symptom before discharge. Daily supervision at the primary health care center with continuous antibiotic treatment was recommended to the patient. Pertinent literature with controversies in the management of subdural empyema will be briefly discussed in this case report. | Is subdural empyema a complication of sinusitis? | Subdural empyema is a rare but potentially life-threatening complication following paranasal sinusitis and should be considered as a neurological emergency. |
Transcription factor binding sites (TFBSs) are most commonly characterized by the nucleotide preferences at each position of the DNA target. Whereas these sequence motifs are quite accurate descriptions of DNA binding specificities of transcription factors (TFs), proteins recognize DNA as a three-dimensional object. DNA structural features refine the description of TF binding specificities and provide mechanistic insights into protein-DNA recognition. Existing motif databases contain extensive nucleotide sequences identified in binding experiments based on their selection by a TF. To utilize DNA shape information when analysing the DNA binding specificities of TFs, we developed a new tool, the TFBSshape database (available at http://rohslab.cmb.usc.edu/TFBSshape/), for calculating DNA structural features from nucleotide sequences provided by motif databases. The TFBSshape database can be used to generate heat maps and quantitative data for DNA structural features (i.e., minor groove width, roll, propeller twist and helix twist) for 739 TF datasets from 23 different species derived from the motif databases JASPAR and UniPROBE. As demonstrated for the basic helix-loop-helix and homeodomain TF families, our TFBSshape database can be used to compare, qualitatively and quantitatively, the DNA binding specificities of closely related TFs and, thus, uncover differential DNA binding specificities that are not apparent from nucleotide sequence alone. | What is TFBSshape? | To utilize DNA shape information when analysing the DNA binding specificities of TFs, we developed a new tool, the TFBSshape database (available at http://rohslab.cmb.usc.edu/TFBSshape/), for calculating DNA structural features from nucleotide sequences provided by motif databases. The TFBSshape database can be used to generate heat maps and quantitative data for DNA structural features (i.e., minor groove width, roll, propeller twist and helix twist) for 739 TF datasets from 23 different species derived from the motif databases JASPAR and UniPROBE. As demonstrated for the basic helix-loop-helix and homeodomain TF families, our TFBSshape database can be used to compare, qualitatively and quantitatively, the DNA binding specificities of closely related TFs and, thus, uncover differential DNA binding specificities that are not apparent from nucleotide sequence alone. |
Somatic mutations of calreticulin (CALR) have been identified as a main disease driver of myeloproliferative neoplasms, suggesting that development of drugs targeting mutant CALR is of great significance. Site-directed mutagenesis in the N-glycan binding domain (GBD) abolishes the ability of mutant CALR to oncogenically activate the thrombopoietin receptor (MPL). We therefore hypothesized that a small molecule targeting the GBD might inhibit the oncogenicity of the mutant CALR. Using an in silico molecular docking study, we identified candidate binders to the GBD of CALR. Further experimental validation of the hits identified a group of catechols inducing a selective growth inhibitory effect on cells that depend on oncogenic CALR for survival and proliferation. Apoptosis-inducing effects by the compound were significantly higher in the CALR-mutated cells than in CALR wild-type cells. Additionally, knockout or C-terminal truncation of CALR eliminated drug hypersensitivity in CALR-mutated cells. We experimentally confirmed the direct binding of the selected compound to CALR, disruption of the mutant CALR-MPL interaction, inhibition of the JAK2-STAT5 pathway, and reduction at the intracellular level of mutant CALR upon drug treatment. Our data indicate that small molecules targeting the GBD of CALR can selectively kill CALR-mutated cells by disrupting the CALR-MPL interaction and inhibiting oncogenic signaling. | Which disease is caused by mutations in the gene CALR? | Somatic mutations of calreticulin (CALR) have been identified as a main disease driver of myeloproliferative neoplasms, |
On the histone H3 tail, Lys 9 and Lys 27 are both methylation sites associated with epigenetic repression, and reside within a highly related sequence motif ARKS. Here we show that the chromodomain proteins Polycomb (Pc) and HP1 (heterochromatin protein 1) are highly discriminatory for binding to these sites in vivo and in vitro. In Drosophila S2 cells, and on polytene chromosomes, methyl-Lys 27 and Pc are both excluded from areas that are enriched in methyl-Lys 9 and HP1. Swapping of the chromodomain regions of Pc and HP1 is sufficient for switching the nuclear localization patterns of these factors, indicating a role for their chromodomains in both target site binding and discrimination. To better understand the molecular basis for the selection of methyl-lysine binding sites, we solved the 1.8 A structure of the Pc chromodomain in complex with a H3 peptide bearing trimethyl-Lys 27, and compared it with our previously determined structure of the HP1 chromodomain in complex with a H3 peptide bearing trimethyl-Lys 9. The Pc chromodomain distinguishes its methylation target on the H3 tail via an extended recognition groove that binds five additional residues preceding the ARKS motif. | Which histone mark is recognized by HP1? | To better understand the molecular basis for the selection of methyl-lysine binding sites, we solved the 1.8 A structure of the Pc chromodomain in complex with a H3 peptide bearing trimethyl-Lys 27, and compared it with our previously determined structure of the HP1 chromodomain in complex with a H3 peptide bearing trimethyl-Lys 9. |
Inflammatory bowel diseases (IBD) are known as chronic inflammatory disorders of the digestive tract, represented mainly by Crohn's disease (CD) and ulcerative colitis (UC). Among the main oral manifestations of IBD are cobblestoning of the oral mucosa, labial swellings with vertical fissures, pyostomatitis vegetans, angular cheilitis, perioral erythema, and glossitis. In this sense, understanding these nosological entities by dentists would help reach early and differential diagnosis. Thus, two case reports are presented and discussed based on theoretical references obtained by a literature review. The first case report refers to an adult patient whose IBD diagnosis was established after stomatological assessment. The second case was a patient with CD diagnosed in childhood with characteristic oral lesions. | Is there an association between pyostomatitis vegetans and Crohn's disease? | Among the main oral manifestations of IBD are cobblestoning of the oral mucosa, labial swellings with vertical fissures, pyostomatitis vegetans, angular cheilitis, perioral erythema, and glossitis. |
Oral amitriptyline has been used as an analgesic in a wide range of pain settings. Despite long-term availability of a parenteral form, the few reports about this formulation have been limited to pharmacokinetic studies in normal volunteers, trials in depressed patients, and analyses of electroencephalogram (EEG) activation. We retrospectively reviewed our experience using intravenous (IV) amitriptyline at Children's Hospital, Boston and at Children's Hospital at Stanford. Eight children (aged 5-16.6 years), who were unable to tolerate medications by the oral route, received IV amitriptyline for a variety of indications, including neuropathic pain, depression, sleep disturbance, and as an adjuvant agent for opioid analgesia. One patient experienced an extrapyramidal reaction temporally related to the administration of IV amitriptyline, which was successfully managed with diphenhydramine. Further prospective, controlled studies are needed to further assess the safety, efficacy and tolerability of this novel use of amitriptyline. | What is the treatment of neuropathic pain in children? | Oral amitriptyline has been used as an analgesic in a wide range of pain settings. Despite long-term availability of a parenteral form, the few reports about this formulation have been limited to pharmacokinetic studies in normal volunteers, trials in depressed patients, and analyses of electroencephalogram (EEG) activation. We retrospectively reviewed our experience using intravenous (IV) amitriptyline at Children's Hospital, Boston and at Children's Hospital at Stanford. Eight children (aged 5-16.6 years), who were unable to tolerate medications by the oral route, received IV amitriptyline for a variety of indications, including neuropathic pain, depression, sleep disturbance, and as an adjuvant agent for opioid analgesia. |
Genomic aberrations and gene expression-defined subtypes in the large METABRIC patient cohort have been used to stratify and predict survival. The present study used normalized gene expression signatures of paclitaxel drug response to predict outcome for different survival times in METABRIC patients receiving hormone (HT) and, in some cases, chemotherapy (CT) agents. This machine learning method, which distinguishes sensitivity vs. resistance in breast cancer cell lines and validates predictions in patients; was also used to derive gene signatures of other HT (tamoxifen) and CT agents (methotrexate, epirubicin, doxorubicin, and 5-fluorouracil) used in METABRIC. Paclitaxel gene signatures exhibited the best performance, however the other agents also predicted survival with acceptable accuracies. A support vector machine (SVM) model of paclitaxel response containing genes and was 78.6% accurate in predicting survival of 84 patients treated with both HT and CT (median survival ≥ 4.4 yr). Accuracy was lower (73.4%) in 304 untreated patients. The performance of other machine learning approaches was also evaluated at different survival thresholds. Minimum redundancy maximum relevance feature selection of a paclitaxel-based SVM classifier based on expression of genes and was 81.1% accurate in 53 CT patients. In addition, a random forest (RF) classifier using a gene signature ( and ) predicted >3-year survival with 85.5% accuracy in 420 HT patients. A similar RF gene signature showed 82.7% accuracy in 504 patients treated with CT and/or HT. These results suggest that tumor gene expression signatures refined by machine learning techniques can be useful for predicting survival after drug therapies. | What is the aim of the METABRIC project? | The present study used normalized gene expression signatures of paclitaxel drug response to predict outcome for different survival times in METABRIC patients receiving hormone (HT) and, in some cases, chemotherapy (CT) agents. |
Williams syndrome (WS) is a neurodevelopmental genetic disorder associated with high rates of anxiety and social issues. We examined diurnal cortisol, a biomarker of the stress response, in adults with WS in novel and familiar settings, and compared these profiles to typically developing (TD) adults. WS and TD participants had similar profiles in a familiar setting, while participants with WS had elevated cortisol late in the day in the novel setting when social demands were higher. The cortisol awakening response in WS was associated with parent-reported levels of somatic complaints and social difficulties. Results suggest that adults with WS have a typical diurnal cortisol profile that may be sensitive to social and activity transitions throughout the day. | Which hormone abnormalities are common in Williams syndrome | Results suggest that adults with WS have a typical diurnal cortisol profile |
In eukaryotic organisms, initiation of mRNA turnover is controlled by progressive shortening of the poly-A tail, a process involving the mega-Dalton Ccr4-Not complex and its two associated 3'-5' exonucleases, Ccr4p and Pop2p (Caf1p). RNA degradation by the 3'-5' DEDDh exonuclease, Pop2p, is governed by the classical two metal ion mechanism traditionally assumed to be dependent on Mg(2+) ions bound in the active site. Here, we show biochemically and structurally that fission yeast (Schizosaccharomyces pombe) Pop2p prefers Mn(2+) and Zn(2+) over Mg(2+) at the concentrations of the ions found inside cells and that the identity of the ions in the active site affects the activity of the enzyme. Ion replacement experiments further suggest that mRNA deadenylation could be subtly regulated by local Zn(2+) levels in the cell. Finally, we use site-directed mutagenesis to propose a mechanistic model for the basis of the preference for poly-A sequences exhibited by the Pop2p-type deadenylases as well as their distributive enzymatic behavior. | What is the role of deadenylases in the cell? | Here, we show biochemically and structurally that fission yeast (Schizosaccharomyces pombe) Pop2p prefers Mn(2+) and Zn(2+) over Mg(2+) at the concentrations of the ions found inside cells and that the identity of the ions in the active site affects the activity of the enzyme. |
Cri-du-chat syndrome is caused by haploinsufficiency of the genes on the distal part of the short arm of chromosome 5, and characteristic features include microcephaly, developmental delays, and a distinctive high-pitched mewing cry. Most cri-du-chat syndrome cases result from a sporadic de novo deletion that is associated with a low recurrence risk. On rare occasions, however, cri-du-chat syndrome with 5p monosomy can be accompanied by 5q trisomy. This combination is virtually always associated with parental large pericentric inversions. Among previously reported cri-du-chat syndrome cases with 5p monosomy accompanied by 5q trisomy, the aneusomy of chromosome 5 in all but one case was cytogenetically visible using G-banding. When an accompanying 5q trisomy is detected, a significant recurrence risk is expected. We here report on a patient with cri-du-chat syndrome phenotype who initially exhibited a normal karyotype on G-banding but in whom molecular analysis using multiplex ligation-dependent probe amplification and array comparative genomic hybridization revealed a 5p deletion accompanied by a 5q duplication. Parental chromosomal testing led to the identification of a very large pericentric inversion, of which breakpoints resided at the terminal regions of 5p15.31 and 5q35.1. This information was vital for counseling the family regarding the significantly high recurrence risk. | Is Cri Du Chat associated with an expansion of a repeat with in the gene found on chromosome 5? | Cri-du-chat syndrome is caused by haploinsufficiency of the genes on the distal part of the short arm of chromosome 5, and characteristic features include microcephaly, developmental delays, and a distinctive high-pitched mewing cry. |
Mowat-Wilson syndrome (MWS) is a genetic disease caused by heterozygous mutations or deletions of the ZEB2 gene and is characterized by distinctive facial features, epilepsy, moderate to severe intellectual disability, corpus callosum abnormalities and other congenital malformations. Epilepsy is considered a main manifestation of the syndrome, with a prevalence of about 70-75%. In order to delineate the electroclinical phenotype of epilepsy in MWS, we investigated epilepsy onset and evolution, including seizure types, EEG features, and response to anti-epileptic therapies in 22 patients with genetically confirmed MWS. Onset of seizures occurred at a median age of 14.5 months (range: 1-108 months). The main seizure types were focal and atypical absence seizures. In all patients the first seizure was a focal seizure, often precipitated by fever. The semiology was variable, including hypomotor, versive, or focal clonic manifestations; frequency ranged from daily to sporadic. Focal seizures were more frequent during drowsiness and sleep. In 13 patients, atypical absence seizures appeared later in the course of the disease, usually after the age of 4 years. Epilepsy was usually quite difficult to treat: seizure freedom was achieved in nine out of the 20 treated patients. At epilepsy onset, the EEGs were normal or showed only mild slowing of background activity. During follow-up, irregular, diffuse frontally dominant and occasionally asymmetric spike and waves discharges were seen in most patients. Sleep markedly activated these abnormalities, resulting in continuous or near-to-continuous spike and wave activity during slow wave sleep. Slowing of background activity and poverty of physiological sleep features were seen in most patients. Our data suggest that a distinct electroclinical phenotype, characterized by focal and atypical absence seizures, often preceded by febrile seizures, and age-dependent EEG changes, can be recognized in most patients with MWS. | Have mutations in the ZEB2 gene been found in any human syndrome? | owat-Wilson syndrome (MWS) is a genetic disease caused by heterozygous mutations or deletions of the ZEB2 gene |
Glycogen storage disease type II (Pompe disease) is inherited by autosomal recessive transmission and caused by a deficiency of acid alpha-glucosidase (GAA), resulting in impaired degradation and lysosomal accumulation of glycogen. The GAA gene, responsible for this disease, has been mapped to chromosome 17q25.2-25.3. To date, more than 70 disease-causing mutations have been identified. In this study, we present four mutations found in three Japanese patients with the juvenile form of glycogen storage disease type II; three of these mutations were new (R224W, S619R, and R660H). The pathogenicity of these new mutations was verified by the loss of function of the mutant enzymes expressed in COS cells. | Is acid alpha-glucosidase the enzyme that causes Pompe disease when mutant? | Glycogen storage disease type II (Pompe disease) is inherited by autosomal recessive transmission and caused by a deficiency of acid alpha-glucosidase (GAA), resulting in impaired degradation and lysosomal accumulation of glycogen |
Functional intracellular Ca(2+) signaling is essential for the upregulation of the canonical mTOR-controlled autophagy pathway triggered by rapamycin or by nutrient deprivation. Moreover, modifications in the Ca(2+)-signaling machinery coincide with autophagy stimulation. This results in enhanced intracellular Ca(2+) signaling essential for driving the autophagy process. Yet, the mechanisms upstream (the players causing the changes in Ca(2+) signaling) and downstream (the targets of the altered Ca(2+) signals) of this Ca(2+)-dependent autophagy pathway remain elusive. Here, we speculate about these mechanisms based on our current knowledge. | Does the protein mTOR regulate autophagy? | the canonical mTOR-controlled autophagy pathway |
Gaucher's disease (GD) results from a deficiency of the lysosomal enzyme glucocerebrosidase and, in very rare occasions, a deficiency of its activator, the saposin C. The complexity of identification and characterization of mutations in the gene of glucocerebrosidase (GBA1) is caused by a great amount of mutated alleles, the existence of a highly homologous pseudogene and its location in a very rich zone in genes, which promotes the presence of complex alleles. Although genotype-phenotype correlations in EG are not completely established, there are a series of generalities, as the mutation c.1226A>G (N370S) is often associated with a certain degree of neuroprotection and the homozygosity for the c.1448T>C (L444P) mutation presents with neurological symptoms. | What is the gene mutated in the Gaucher disease? | (GD) results from a deficiency of the lysosomal enzyme glucocerebrosidase |
Metabolic syndrome (MetS), conventionally defined by the presence of at least three out of five dismetabolic traits (abdominal obesity, hypertension, low plasma HDL-cholesterol and high plasma glucose and triglycerides), has been associated with both breast cancer (BC) incidence and prognosis. We investigated the association between the prevalence of MetS and a score of adherence to the World Cancer Research Fund (WCRF) and American Institute for Cancer Research (AICR) recommendations for the prevention of cancer in a cross-sectional study of BC patients. The DIet and ANdrogen-5 study (DIANA-5) for the prevention of BC recurrences recruited 2092 early stage BC survivors aged 35-70. At recruitment, all women completed a 24-hour food frequency and physical activity diary on their consumption and activity of the previous day. Using these diaries we created a score of adherence to five relevant WCRF/AICR recommendations. The prevalence ratios (PRs) and 95% confidence intervals (CIs) of MetS associated with the number of recommendations met were estimated using a binomial regression model. The adjusted PRs of MetS decreased with increasing number of recommendations met (p < 0.001). Meeting all the five recommendations versus meeting none or only one was significantly associated with a 57% lower MetS prevalence (95% CI 0.35-0.73). Our results suggest that adherence to WCRF/AICR recommendations is a major determinant of MetS and may have a clinical impact. | What are the five traits associated with metabolic syndrome? | Metabolic syndrome (MetS), conventionally defined by the presence of at least three out of five dismetabolic traits (abdominal obesity, hypertension, low plasma HDL-cholesterol and high plasma glucose and triglycerides), has been associated with both breast cancer (BC) incidence and prognosis. We inv |
Diacylglycerol-O-acyltransferase (DGAT1) gene encodes the rate-limiting enzyme of triglyceride synthesis. A polymorphism in this gene, DGAT1 K232A, has been associated with milk production and composition in taurine breeds. However, this polymorphism is not a good tool for ascertaining the effects of this QTL in Bos indicus (Zebu), since the frequency of the DGAT1 232A allele is too low in these breeds. We sequenced the 3'-untranslated region of DGAT1 gene in a sample of bulls of the breeds Guzerá (Bos indicus) and Holstein (Bos taurus) and, using in silico analysis, we searched for genetic variation, evolutionary conservation, regulatory elements, and possible substitution effects. Six single nucleotide (SNPs) and one insertion-deletion (INDEL) polymorphisms were found in the Guzerá bulls. Additionally, we developed a preliminary association study, using this INDEL polymorphism as a genetic marker. A significant association was detected (P ≤ 0.05) between the INDEL (DGAT1 3'UTR INDEL) and the breeding values (BV) for protein, fat, and milk yields over a 305-day lactation period. The DGAT1 3' UTR INDEL genotype I/I (I, for insertion) was associated with lower BVs (-38.77 kg for milk, -1.86 kg for fat, and -1.48 kg for protein yields), when compared to the genotype I/D (D, for deletion). I/D genotype was lower D/D genotype (-34.98 kg milk, -1.73 kg fat, and -1.09 kg protein yields). This study reports the first polymorphism of DGAT1 3'UTR in the Guzerá breed, as well as its association with BV for milk protein, fat, and milk yields. | What is the function of the DGAT1 gene product? | Diacylglycerol-O-acyltransferase (DGAT1) gene encodes the rate-limiting enzyme of triglyceride synthesis. |
Nephropathic cystinosis is an autosomal recessive inborn error of metabolism characterized by the lysosomal storage of the disulphide amino acid cystine. It produces a variety of clinical manifestations including failure to thrive, the renal Fanconi syndrome, eye findings, and end-stage renal disease. A variety of phenotypes are known; however, the molecular defect underlying any of the forms has not yet been identified. Therapy of cystinosis with cysteamine averts the otherwise inevitable renal failure, but systemic therapy does not improve the corneal keratopathy. A number of presentations in this review detail approaches to gene identification, systemic therapy with cysteamine, measurement of cystine, and pathophysiological effects at the cellular and clinical level. | What is nephropathic cystinosis? | Nephropathic cystinosis is an autosomal recessive inborn error of metabolism characterized by the lysosomal storage of the disulphide amino acid cystine. |
Not too long ago, the concept of selectively targeting mRNA with small molecules was perceived as a formidable scientific challenge. The discovery of small molecule splicing modifiers and the development of risdiplam for the treatment of spinal muscular atrophy (SMA) have firmly established proof of concept for this exciting new platform and transformed a scientific curiosity into a viable technology to target disease. Today, several approaches to target mRNA with small molecules, supported by biophysical and screening methods, are in place to deliver new drugs with high therapeutic relevance. | Which disease is treated with Risdiplam? | The discovery of small molecule splicing modifiers and the development of risdiplam for the treatment of spinal muscular atrophy (SMA) have firmly established proof of concept for this exciting new platform and transformed a scientific curiosity into a viable technology to target disease. |
The carpal tunnel syndrome is the most frequent entrapment syndrome of peripheral nerves. Either a diminution of the volume of the whole carpal tunnel or increasement of the intracarpal structures can enhance the pressure on the median nerve and so develop a carpal tunnel syndrome. Fibrosis or thickening of the synovia of the wrist joint is the most common cause of the syndrome, that appears usually in women more than 50 years old. Irradiating pain and sensory disturbances are the most frequent subjective complaints. Motoric changes appear in a minority of patients with the syndrome. The operative procedure is done ambulatory with brachial plexus anesthesia. The subcutaneous 'ramus palmaris nervi mediani' should be treated carefully when releasing the transverse ligament. After a mean time of 24.1 months, 28 of carpal tunnel syndromes treated operatively had a significant amelioration. Seven patients had recurrent sensible or motoric complaints, one of them was operated on a second time. Postoperative recurrent carpal tunnel syndrome mostly is due to inadequate technique or fibrous proliferations. | Is carpal tunnel syndrome a type of nerve entrapment? | The carpal tunnel syndrome is the most frequent entrapment syndrome of peripheral nerves. |
A dysfunction of multiple neurotransmitter systems is assumed as a neurochemical basis of the akinetic-rigid syndrome of progressive supranuclear palsy (PSP). In vitro studies have produced conflicting results on the serotoninergic system in PSP. We, therefore, studied the binding potential of the serotonin 2A (5-HT(2A)) receptor ligand [18F]altanserin in 8 patients with clinically probable PSP and 13 healthy controls using positron emission tomography. We found an up-regulation of 5-HT(2A) receptors in the substantia nigra and, to a lower degree, in the striatum, while neocortical 5- HT(2A) receptor densities showed no changes upon partial-volume correction. Nigral and striatal receptor changes were significantly correlated with patients' scores of motor dysfunction (UPDRS III, PSP-rating scale) pointing to a functional relevance of the described findings. | Which receptors can be evaluated with the [18F]altanserin? | We, therefore, studied the binding potential of the serotonin 2A (5-HT(2A)) receptor ligand [18F]altanserin in 8 patients with clinically probable PSP and 13 healthy controls using positron emission tomography. |
Binding of heterochromatin protein 1 (HP1) to the histone H3 lysine 9 trimethylation (H3K9me3) mark is a hallmark of establishment and maintenance of heterochromatin. Although genetic and cell biological aspects have been elucidated, the molecular details of HP1 binding to H3K9me3 nucleosomes are unknown. Using a combination of NMR spectroscopy and biophysical measurements on fully defined recombinant experimental systems, we demonstrate that H3K9me3 works as an on/off switch regulating distinct binding modes of hHP1β to the nucleosome. The methyl-mark determines a highly flexible and very dynamic interaction of the chromodomain of hHP1β with the H3-tail. There are no other constraints of interaction or additional multimerization interfaces. In contrast, in the absence of methylation, the hinge region and the N-terminal tail form weak nucleosome contacts mainly with DNA. In agreement with the high flexibility within the hHP1β-H3K9me3 nucleosome complex, the chromoshadow domain does not provide a direct binding interface. Our results report the first detailed structural analysis of a dynamic protein-nucleosome complex directed by a histone modification and provide a conceptual framework for understanding similar interactions in the context of chromatin. | Which histone mark is recognized by HP1? | Binding of heterochromatin protein 1 (HP1) to the histone H3 lysine 9 trimethylation (H3K9me3) mark is a hallmark of establishment and maintenance of heterochromatin. Al |
In normal weight persons with impaired glucose tolerance (IGT; normal fasting glycaemia and pathological glucose tolerance) and still normal or already decreased insulin secretion the influence of glibenclamide (maninil) on the carbohydrate and lipid metabolism as well as the insulin secretion was studied after one year (n = 18), after 2 years (n =13), after 3 years (n = 10) and after 5 years (n = 6). Glucose tolerance and insulin secretion were characterized by means of a 2 hours' glucose infusion test (0.33 g/kg as bolus and 12 mg/kg/min over 120 min). In no case the diabetes became manifest during the 5-year duration of the observation. An improvement of the glucose tolerance could be observed up to 3 years, whereas after a 5-year glibenclamide therapy no certain influence on the glucose tolerance and insulin secretion could be proved. In general the improvement of the glucose tolerance was not associated with an increased secretion of insulin, so that an extrapancreatic effect of glibenclamide (improvement of the peripheral insulin sensitivity?) seems to be possible. A complete normalization of the glucose tolerance could be observed only in some individual cases. The body-weight remained constant in all groups, whereas the concentration of triglyceride and cholesterol decreased in their tendency. From clinical and practical point of view the findings would support the opinion that normal weight persons with IGT, particularly in already decreased insulin secretion, have an indication for a glibenclamide therapy. | What is the indication of Daonil (Glibenclamide)? | In general the improvement of the glucose tolerance was not associated with an increased secretion of insulin, so that an extrapancreatic effect of glibenclamide (improvement of the peripheral insulin sensitivity?) seems to be possible. |
miRNAs have recently emerged as key regulators of the immune system, being involved in lymphocyte selection and proliferation, in T(reg) cells differentiation, and in hematopoiesis in general. Rheumatoid arthritis (RA) is an autoimmune pathology the etiology of which is still obscure. Although a multifactorial pathogenesis has been hypothesized, the precise mechanisms leading to the disease are still poorly understood at the molecular level. miRNA expression profile analysis highlighted that miR-223 is the only miRNA that is strikingly deregulated in peripheral T-lymphocytes from RA patients compared with healthy donors. Further analysis by quantitative reverse transcription-polymerase chain analysis confirmed that miR-223 is overexpressed in T-lymphocytes from RA patients (n = 28) compared with healthy donors (n = 10). Moreover, purification of different T-lymphocyte populations from RA patients highlights that miR-223 is expressed at higher levels in naive CD4(+) lymphocytes, whereas its expression is barely detectable in T(h)-17 cells. In summary, our data provide a first characterization of the miRNA expression profiles of peripheral T-lymphocytes of RA patients, identifying miR-223 as overexpressed in CD4(+) naive T-lymphocytes from these individuals. A deeper analysis of the biologic functions and effects of the expression of miR-223 in T-lymphocytes is needed to clarify the exact link between our observation and the disease. | Which micro-RNAs have been associated in the pathogenesis of Rheumatoid Arthritis? | Although a multifactorial pathogenesis has been hypothesized, the precise mechanisms leading to the disease are still poorly understood at the molecular level. miRNA expression profile analysis highlighted that miR-223 is the only miRNA that is strikingly deregulated in peripheral T-lymphocytes from RA patients compared with healthy donors |
Allogeneic hematopoietic cell transplants (allo-HCT) recipients are at the high-risk of reactivation of cytomegalovirus (CMV), and reactivation is associated with significant morbidity and mortality. Although available anti-CMV therapies may be effective for the prevention of CMV, they are plagued by unacceptable toxicities that prohibit their use in the post-transplant period. Recently studied CMV-active agents, such as maribavir and brincidofovir, failed to reduce the incidence of CMV infection in HCT recipients. Letermovir represents the first agent in the non-nucleoside 3,4 dihydro-quinazoline class of CMV viral terminase complex inhibitors, with activity solely against CMV. The positive results from the recently published Phase III study of letermovir for prevention of CMV infection in CMV-seropositive allo-HCT recipients led to its approval as a prophylactic agent for CMV in multiple countries. Areas covered: In this review, we will evaluate this novel agent with a focus on letermovir mechanism of action, pharmacokinetics and metabolism, clinical efficacy, and safety and toxicities. Expert commentary: With the introduction of letermovir, prevention of CMV infection in allo-HCT recipients may shift considerably, from a predominantly preemptive strategy to one that utilizes this novel therapy for prophylaxis. | List two indications of Letermovir? | Expert commentary: With the introduction of letermovir, prevention of CMV infection in allo-HCT recipients may shift considerably, from a predominantly preemptive strategy to one that utilizes this novel therapy for prophylaxis. |
Type 1 fimbriae and flagella, two surface organelles critical for colonization of the urinary tract by uropathogenic Escherichia coli (UPEC), mediate opposing virulence objectives. Type 1 fimbriae facilitate adhesion to mucosal cells and promote bacterial persistence in the urinary tract, while flagella propel bacteria through urine and along mucous layers during ascension to the upper urinary tract. Using a transposon screen of the E. coli CFT073 fim locked-ON (L-ON) mutant, a construct that constitutively expresses type 1 fimbriae and represses motility, we identified six mutants that exhibited a partial restoration of motility. Among these six mutated genes was mutS, which encodes a component of the methyl-directed mismatch repair (MMR) system. When complemented with mutS in trans, motility was again repressed. To determine whether the MMR system, in general, is involved in this reciprocal control, we characterized the effects of gene deletions of other MMR components on UPEC motility. Isogenic deletions of mutS, mutH, and mutL were constructed in both wild-type CFT073 and fim L-ON backgrounds. All MMR mutants showed an increase in motility in the wild-type background, and ΔmutH and ΔmutS mutations increased motility in the fim L-ON background. Cochallenge of the wild-type strain with an MMR-defective strain showed a subtle but significant competitive advantage in the bladder and spleen for the MMR mutant using the murine model of ascending urinary tract infection after 48 h. Our findings demonstrate that the MMR system generally affects the reciprocal regulation of motility and adherence and thus could contribute to UPEC pathogenesis during urinary tract infections. | Which proteins constitute the methyl-directed mismatch repair system (MMR) in bacteria? | Among these six mutated genes was mutS, which encodes a component of the methyl-directed mismatch repair (MMR) system. |
Nup153 is a large (153 kD) O-linked glyco-protein which is a component of the basket structure located on the nucleoplasmic face of nuclear pore complexes. This protein exhibits a tripartite structure consisting of a zinc finger domain flanked by large (60-70 kD) NH2- and COOH-terminal domains. When full-length human Nup153 is expressed in BHK cells, it accumulates appropriately at the nucleoplasmic face of the nuclear envelope. Targeting information for Nup153 resides in the NH2-terminal domain since this region of the molecule can direct an ordinarily cytoplasmic protein, pyruvate kinase, to the nuclear face of the nuclear pore complex. Overexpression of Nup153 results in the dramatic accumulation of nuclear poly (A)+ RNA, suggesting an inhibition of RNA export from the nucleus. This is not due to a general decline in nucleocytoplasmic transport or to occlusion or loss of nuclear pore complexes since nuclear protein import is unaffected. While overexpression of certain Nup153 constructs was found to result in the formation of unusual intranuclear membrane arrays, this structural phenotype could not be correlated with the effects on poly (A)+ RNA distribution. The RNA trafficking defect was, however, dependent upon the Nup153 COOH-terminal domain which contains most of the XFXFG repeats. It is proposed that this region of Nup153, lying within the distal ring of the nuclear basket, represents a docking site for mRNA molecules exiting the nucleus. | Which proteins form the nuclear pore basket in human cells? | Targeting information for Nup153 resides in the NH2-terminal domain since this region of the molecule can direct an ordinarily cytoplasmic protein, pyruvate kinase, to the nuclear face of the nuclear pore complex. |
Chronic spontaneous urticaria (CSU) is considered to be primarily a mast cell-driven disease. However, recent evidence suggests that eosinophils may also have an axial role in symptomology. Histologic studies have demonstrated the presence of both eosinophils and eosinophil granules, indicative of activation, in CSU lesions. Although many allergic and inflammatory conditions are associated with a peripheral blood eosinophilia, the converse appears to be the case in CSU, with a peripheral blood eosinopenia being observed in many patients. Possible mechanisms include the depletion of blood eosinophils by recruitment into the skin during active disease and immunologic destruction in the blood. We also address in some detail the interactions between eosinophils and mast cells, particularly the cytokine cross-talk of these cells and mediator release possibly leading to clinical symptoms. Also, activation by eosinophil proteins of the coagulation pathway leads to the generation of thrombin and increased mast cell degranulation. Finally, treatments aimed at reducing eosinophil accumulation and activation, such as the anti-IL-5 antibodies mepolizumab, reslizumab, and benralizumab, have been reported to reduce CSU symptoms. Clearly, a new picture of an important role of eosinophils in the pathogenesis of CSU is emerging. | Is Benralizumab effective for Chronic Spontaneous Urticaria? | Finally, treatments aimed at reducing eosinophil accumulation and activation, such as the anti-IL-5 antibodies mepolizumab, reslizumab, and benralizumab, have been reported to reduce CSU symptoms. |
With the development of highly effective, well-tolerated third-generation aromatase inhibitors (AIs), these drugs will probably play an increasingly important role in all phases of breast cancer treatment. As a result, the impact of such hormonal agents on patients' quality of life bears rigorous investigation. In a randomized, multicenter, single-blind cross-over study, the AIs letrozole and anastrozole were evaluated for quality of life, toxicity, and patient preference. A total of 72 patients were enrolled and were treated with each drug for a 4-week period, with a 1-week drug-free washout period before cross-over to the alternate agent. Assessments included the FACT-ES, toxicity, and patient preference. The FACT-ES is a validated questionnaire designed to measure quality of life of women with breast cancer who are being treated with endocrine therapies. Letrozole was superior to anastrozole with respect to both quality of life and toxicity evaluations. In addition, at the conclusion of the trial, reduced nausea, hot flashes, and abdominal discomfort caused almost twice as many patients to prefer to continue with letrozole therapy than with anastrozole. Data from this recent trial indicate that letrozole is better tolerated and provides better quality of life than anastrozole for women with metastatic breast cancer. | Could Arimidex (anastrozole) cause hot flashes? | reduced nausea, hot flashes, and abdominal discomfort caused almost twice as many patients to prefer to continue with letrozole therapy than with anastrozole |
The endothelin signaling pathway plays a crucial role in melanocyte differentiation and migration. In this study, we investigated whether germline mutations of endothelin receptor B (EDNRB), a gene involved in Hirschsprung disease (HSCR), could also predispose for malignant melanoma (MM). The coding region of EDNRB was sequenced in 137 MM patients and in 130 ethnically matched Caucasian control subjects. Six nonsynonymous EDNRB variants were found in 15 patients (11%), but only two were found in four control subjects (3%, odds ratio [OR] = 3.87, 95% confidence interval [CI] = 1.25 to 12; P = .012). Overall, 14 out of 15 MM patients carried EDNRB mutations reported in HSCR, some of which had previously been shown to lead to loss of function. In multivariable logistic regression analysis including skin type, eye and hair color, number of nevi, and dorsal lentigines (freckles), the association between EDNRB mutations and MM risk remained statistically significant (OR = 19.9, 95% CI = 1.34 to 296.2; P = .03). Our data strongly suggest that EDNRB is involved in predisposition for two different multigenic disorders, HSCR and melanoma. | Are EDNRB mutations involved in the development of Hirschsprung disease? | Our data strongly suggest that EDNRB is involved in predisposition for two different multigenic disorders, HSCR and melanoma. |
Certain anticonvulsants, cyclosporine, and a variety of calcium channel blockers have been shown to produce clinically and histologically similar gingival enlargements in certain susceptible patients. These drugs appear to be similar with respect to their pharmacologic mechanism of action at the cellular level. The primary target tissue is the most essential difference among them. Therefore it is tempting to speculate that these agents may act similarly on a common secondary target tissue, such as gingival connective tissue, and cause a hyperplastic response. This tissue reaction may involve a disturbance of calcium ion influx into specific cell populations with a resulting alteration in collagen metabolism and other host cell response mechanisms. A connection between ion exchange, folate uptake, collagenase activation, and bacterial inflammation may exist. Until a more effective approach can be developed from future research results, treatment should continue to emphasize plaque control, professional debridement, and resective gingival procedures to improve function, esthetics, and access for home care. | What is the mechanism of drug-induced gingival overgrowth? | Certain anticonvulsants, cyclosporine, and a variety of calcium channel blockers have been shown to produce clinically and histologically similar gingival enlargements in certain susceptible patients |
Feline infectious peritonitis (FIP) is one of the most important infectious diseases in cats and is caused by feline coronavirus (FCoV). Tissue culture-adapted type I FCoV shows reduced FIP induction in experimental infections, which complicates the understanding of FIP pathogenesis caused by type I FCoV. We previously found that the type I FCoV strain C3663 efficiently induces FIP in specific-pathogen-free cats through the naturally infectious route. In this study, we employed a bacterial artificial chromosome-based reverse genetics system to gain more insights into FIP caused by the C3633 strain. We successfully generated recombinant virus (rC3663) from Fcwf-4 cells transfected with infectious cDNA that showed growth kinetics similar to those shown by the parental virus. Next, we constructed a reporter C3663 virus carrying the nanoluciferase (Nluc) gene to measure viral replication with high sensitivity. The inhibitory effects of different compounds against rC3663-Nluc could be measured within 24 h postinfection. Furthermore, we found that A72 cells derived from canine fibroblasts permitted FCoV replication without apparent cytopathic effects. Thus, our reporter virus is useful for uncovering the infectivity of type I FCoV in different cell lines, including canine-derived cells. Surprisingly, we uncovered aberrant viral RNA transcription of rC3663 in A72 cells. Overall, we succeeded in obtaining infectious cDNA clones derived from type I FCoV that retained its virulence. Our recombinant FCoVs are powerful tools for increasing our understanding of the viral life cycle and pathogenesis of FIP-inducing type I FCoV. Feline coronavirus (FCoV) is one of the most significant coronaviruses, because this virus induces feline infectious peritonitis (FIP), which is a lethal disease in cats. Tissue culture-adapted type I FCoV often loses pathogenicity, which complicates research on type I FCoV-induced feline infectious peritonitis (FIP). Since we previously found that type I FCoV strain C3663 efficiently induces FIP in specific-pathogen-free cats, we established a reverse genetics system for the C3663 strain to obtain recombinant viruses in the present study. By using a reporter C3663 virus, we were able to examine the inhibitory effect of 68 compounds on C3663 replication in Fcwf-4 cells and infectivity in a canine-derived cell line. Interestingly, one canine cell line, A72, permitted FCoV replication but with low efficiency and aberrant viral gene expression. | The virus that causes FIP, Feline Infectious Peritonitis belongs to what family? | Feline infectious peritonitis (FIP) is one of the most important infectious diseases in cats and is caused by feline coronavirus (FCoV). |
The utility of measuring salivary cortisol has become increasingly appreciated since the early 1980s. Salivary cortisol is a measure of active free cortisol and follows the diurnal rhythm of serum or plasma cortisol. The saliva sample may be collected by drooling or through the use of absorbent swabs which are placed into the mouth until saturated. Salivary cortisol is therefore convenient for patients and research participants to collect noninvasively on an outpatient basis. Several assay techniques have been used to measure salivary cortisol, including radioimmunoassay and more recently liquid chromatography-tandem mass spectrometry. The analytical sensitivity varies between these assay methods, as does the potential for cross-reactivity with other steroids. The interpretation of salivary cortisol levels relies on rigorous standardization of sampling equipment, sampling protocols and assay technology with establishment of a local reference range. Clinically, the commonest use for salivary cortisol is measuring late-night salivary cortisol as a screening test for Cushing's syndrome. Several studies have shown diagnostic sensitivities and specificities of over 90%, which compares very favourably with other screening tests for Cushing's syndrome such as the 24-h urinary-free cortisol and the 1-mg overnight dexamethasone suppression test. There are emerging roles for the use of salivary cortisol in diagnosing adrenal insufficiency, particularly in conditions associated with low cortisol-binding globulin levels, and in the monitoring of glucocorticoid replacement. Finally, salivary cortisol has been used extensively as a biomarker of stress in a research setting, especially in studies examining psychological stress with repeated measurements. | Salivary Cortisol is a biomarker for what disease/syndrome/condition? | Finally, salivary cortisol has been used extensively as a biomarker of stress in a research setting, especially in studies examining psychological stress with repeated measurements. |
The Nkx2-5 homeodomain protein plays a key role in cardiomyogenesis. Ectopic expression in frog and zebrafish embryos results in an enlarged myocardium; however, expression of Nkx2-5 in fibroblasts was not able to trigger the development of beating cardiac muscle. In order to examine the ability of Nkx2-5 to modulate endogenous cardiac specific gene expression in cells undergoing early stages of differentiation, P19 cell lines overexpressing Nkx2-5 were differentiated in the absence of Me2SO. Nkx2-5 expression induced cardiomyogenesis in these cultures aggregated without Me2SO. During differentiation into cardiac muscle, Nkx2-5 expression resulted in the activation of myocyte enhancer factor 2C (MEF2C), but not MEF2A, -B, or -D. In order to compare the abilities of Nkx2-5 and MEF2C to induce cellular differentiation, P19 cells overexpressing MEF2C were aggregated in the absence of Me2SO. Similar to Nkx2-5, MEF2C expression initiated cardiomyogenesis, resulting in the up-regulation of Brachyury T, bone morphogenetic protein-4, Nkx2-5, GATA-4, cardiac alpha-actin, and myosin heavy chain expression. These findings indicate the presence of a positive regulatory network between Nkx2-5 and MEF2C and show that both factors can direct early stages of cell differentiation into a cardiomyogenic pathway. | what is the role of MEF-2 in cardiomyocyte differentiation? | Similar to Nkx2-5, MEF2C expression initiated cardiomyogenesis, resulting in the up-regulation of Brachyury T, bone morphogenetic protein-4, Nkx2-5, GATA-4, cardiac alpha-actin, and myosin heavy chain expression. |
7p22.1 microduplication syndrome is mainly characterized by developmental and speech delay, craniofacial dysmorphisms and skeletal abnormalities. The minimal critical region includes two OMIM genes: ACTB and RNF216. Here, we report on a girl carrying the smallest 7p22.1 microduplication detected to date, contributing to the delineation of the clinical phenotype of the 7p22.1 duplication syndrome and to the refinement of the minimal critical region. Our patient shares several major features of the 7p22.1 duplication syndrome, including craniofacial dysmorphisms and speech and motor delay, but she also presents with renal anomalies. Based on present and published dup7p22.1 patients we suggest that renal abnormalities might be an additional feature of the 7p22.1 microduplication syndrome. We also pinpoint the ACTB gene as the key gene affecting the 7p22.1 duplication syndrome phenotype. | List critical regions for 7p22.1 microduplication syndrome | 7p22.1 microduplication syndrome is mainly characterized by developmental and speech delay, craniofacial dysmorphisms and skeletal abnormalities. The minimal critical region includes two OMIM genes: ACTB and RNF216. Here, we report on a girl carrying the smallest 7p22.1 microduplication detected to date, contributing to the delineation of the clinical phenotype of the 7p22.1 duplication syndrome and to the refinement of the minimal critical region. Our patient shares several major features of the 7p22.1 duplication syndrome, including craniofacial dysmorphisms and speech and motor delay, but she also presents with renal anomalies. Based on present and published dup7p22.1 patients we suggest that renal abnormalities might be an additional feature of the 7p22.1 microduplication syndrome. We also pinpoint the ACTB gene as the key gene affecting the 7p22.1 duplication syndrome phenotype. |
Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc) are highly expressed in embryonic stem (ES) cells, and their over-expression can induce pluripotency in both mouse and human somatic cells, indicating that these factors regulate the developmental signaling network necessary for ES cell pluripotency. However, systemic analysis of the signaling pathways regulated by Yamanaka factors has not yet been fully described. In this study, we identified the target promoters of endogenous Yamanaka factors on a whole genome scale using ChIP (chromatin immunoprecipitation)-on-chip in E14.1 mouse ES cells, and we found that these four factors co-occupied 58 promoters. Interestingly, when Oct4 and Sox2 were analyzed as core factors, Klf4 functioned to enhance the core factors for development regulation, whereas c-Myc seemed to play a distinct role in regulating metabolism. The pathway analysis revealed that Yamanaka factors collectively regulate a developmental signaling network composed of 16 developmental signaling pathways, nine of which represent earlier unknown pathways in ES cells, including apoptosis and cell-cycle pathways. We further analyzed data from a recent study examining Yamanaka factors in mouse ES cells. Interestingly, this analysis also revealed 16 developmental signaling pathways, of which 14 pathways overlap with the ones revealed by this study, despite that the target genes and the signaling pathways regulated by each individual Yamanaka factor differ significantly between these two datasets. We suggest that Yamanaka factors critically regulate a developmental signaling network composed of approximately a dozen crucial developmental signaling pathways to maintain the pluripotency of ES cells and probably also to induce pluripotent stem cells. | Which are the Yamanaka factors? | Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc) are highly expressed in embryonic stem (ES) cells, and their over-expression can induce pluripotency in both mouse and human somatic cells, indicating that these factors regulate the developmental signaling network necessary for ES cell pluripotency. |
The segregation of brown (type IV) oculocutaneous albinism was analyzed in 18 Nigerian families. Analysis using the POINTER program showed that this type of oculocutaneous albinism was inherited in an autosomal recessive pattern, with an estimated gene frequency of 0.025 +/- 0.007 in this population. The enzyme defect responsible for brown oculocutaneous albinism is unknown. | Does oculocutaneous albinism show an autosomal recessive inheritance? | Analysis using the POINTER program showed that this type of oculocutaneous albinism was inherited in an autosomal recessive pattern, with an estimated gene frequency of 0.025 +/- 0.007 in this population. |
Whole genome duplications (WGDs) have been hypothesized to be responsible for major transitions in evolution. However, the effects of WGD and subsequent gene loss on cellular behavior and metabolism are still poorly understood. Here we develop a genome scale evolutionary model to study the dynamics of gene loss and metabolic adaptation after WGD. Using the metabolic network of Saccharomyces cerevisiae as an example, we primarily study the outcome of WGD on yeast as it currently is. However, similar results were obtained using a recontructed hypothetical metabolic network of the pre-WGD ancestor. We show that the retention of genes in duplicate in the model, corresponds nicely with those retained in duplicate after the ancestral WGD in S. cerevisiae. Also, we observe that transporter and glycolytic genes have a higher probability to be retained in duplicate after WGD and subsequent gene loss, both in the model as in S. cerevisiae, which leads to an increase in glycolytic flux after WGD. Furthermore, the model shows that WGD leads to better adaptation than small-scale duplications, in environments for which duplication of a whole pathway instead of single reactions is needed to increase fitness. This is indeed the case for adaptation to high glucose levels. Thus, our model confirms the hypothesis that WGD has been important in the adaptation of yeast to the new, glucose-rich environment that arose after the appearance of angiosperms. Moreover, the model shows that WGD is almost always detrimental on the short term in environments to which the lineage is preadapted, but can have immediate fitness benefits in "new" environments. This explains why WGD, while pivotal in the evolution of many lineages and an apparent "easy" genetic operator, occurs relatively rarely. | Are whole-genome duplications more divergent than small-scale duplications in yeast? | We show that the retention of genes in duplicate in the model, corresponds nicely with those retained in duplicate after the ancestral WGD in S. cerevisiae |
Duchenne muscular dystrophy (DMD) is a rare, fatal X-linked disorder characterized by the lack of dystrophin, a key sarcolemma muscle protein. Cardiac failure is a significant cause of death in DMD subjects. The purpose of our research was to identify potential cardiac serum biomarkers associated with DMD cardiomyopathy. This is an observational, case-controlled study using subjects from the CINRG DMD natural history study with cardiomyopathy (ejection fraction (EF) <55%; shortening fraction (SF) <28%), subjects without cardiomyopathy (EF ≥ 55%; SF ≥ 28%) compared to normal healthy volunteer subjects. The DMD with cardiomyopathy group had significantly lower average EF and SF (EF = 45 ± 10/SF = 25 ± 2%) than the DMD without cardiomyopathy group (EF = 58 ± 5% and SF = 32 ± 3%; p < 0.01). Among a selected set of potential biomarkers for cardiomyopathy (MMP9, BNP, GAL3, CRP, LEP, TNC, TLR4 and ST2) we validated ST2 as significantly elevated in the serum of DMD cardiomyopathy group (35,798 ± 4884 pg/mL) compared to normal controls (9940 ± 2680 pg/mL; p < 0.01; n = 6). Matrix metallopeptidase 9 (MMP9) levels were found significantly increased in both DMD groups compared to controls (p < 0.01). No significant differences were seen in BNP, GAL3, CRP, LEP, TNC or TLR4 levels. Increased ST2 levels were found in serum of DMD subjects compared to healthy volunteers and further elevated in DMD subjects with cardiomyopathy. Future studies correlating cardiomyopathy with ST2 levels may allow for improved non-invasive monitoring of cardiac disease in DMD subjects. | Which biomarkers are currently used for Duchenne Muscular Dystrophy? | Matrix metallopeptidase 9 (MMP9) levels were found significantly increased in both DMD groups compared to controls (p < 0.01). |
Peptidylarginine deiminases (PADs) are a group of posttranslational modification enzymes that citrullinate (deiminate) protein arginine residues in a Ca(2+)-dependent manner. Enzymatic citrullination abolishes positive charges of native protein molecules, inevitably causing significant alterations in their structure and functions. Among the five isoforms of PADs, PAD2 and PAD4 are proved occupants of the central nervous system (CNS), and especially PAD2 is a main PAD enzyme expressed in the CNS. We previously reported that abnormal protein citrullination by PAD2 has been closely associated with the pathogenesis of neurodegenerative disorders such as Alzheimer's disease and prion disease. Protein citrullination in these patients is thought to play a role during the initiation and/or progression of disease. However, the contribution of changes in PAD2 levels, and consequent citrullination, during developmental and aging processes remained unclear. Therefore, we used quantitative real-time RT-PCR, Western blot analysis, and immunohistochemical methods to measure PAD2 expression and localization in the brain during those processes. PAD2 mRNA expression was detected in the brains of mice as early as embryonic day 15, and its expression in cerebral cortex, hippocampus, and cerebellum increased significantly as the animals aged from 3 to 30 months old. No citrullinated proteins were detected during that period. Moreover, we found here, for the first time, that PAD2 localized specifically in the neuronal cells of the cerebral cortex and Purkinje cells of the cerebellum. These findings indicate that, despite PAD2's normally inactive status, it becomes active and citrullinates cellular proteins, but only when the intracellular Ca(2+) balance is upset during neurodegenerative changes. | List diseases where protein citrullination plays an important role. | We previously reported that abnormal protein citrullination by PAD2 has been closely associated with the pathogenesis of neurodegenerative disorders such as Alzheimer's disease and prion disease |
Traffic between the nucleus and cytoplasm takes place through a macromolecular structure termed the nuclear pore complex. To understand how the vital process of nucleocytoplasmic transport occurs, the contribution of individual pore proteins must be elucidated. One such protein, the nucleoporin Nup153, is localized to the nuclear basket of the pore complex and has been shown to be a central component of the nuclear transport machinery. Perturbation of Nup153 function was demonstrated previously to block the export of several classes of RNA cargo. Moreover, these studies also showed that Nup153 can stably associate with RNA in vitro. In this study, we have mapped a domain within Nup153, encompassing amino acids 250-400 in human Nup153, that is responsible for RNA association. After cloning this region of Xenopus Nup153, we performed a cross-species analysis. Despite variation in sequence conservation between Drosophila, Xenopus, and human, this domain of Nup153 displayed robust RNA binding activity in each case, indicating that this property is a hallmark feature of Nup153 and pointing toward a subset of amino acid residues that are key to conferring this ability. We have further determined that a recombinant fragment of Nup153 can bind directly to RNA and that this fragment can interact with endogenous RNA targets. Our findings identify a functionally conserved domain in Nup153 and suggest a role for RNA binding in Nup153 function at the nuclear pore. | Which proteins form the nuclear pore basket in human cells? | One such protein, the nucleoporin Nup153, is localized to the nuclear basket of the pore complex and has been shown to be a central component of the nuclear transport machinery. |
The thyroid hormones triiodothyronine (T3) and L-thyroxine appear to enhance regeneration in the peripheral and central nervous system (CNS). The following experiments examine possible metabolic substrates for the action of T3 on the adult rat CNS after spinal hemisection. The protein incorporation of (3H)lysine after a left spinal hemisection (T2) or control operations was examined 1, 3, 7, and 14 days postoperation. Triiodothyronine (1 microgram/kg body weight in a bicarbonate buffer) was injected daily for the postoperation or equivalent time period. One hour prior to decapitation, animals were given a subcutaneous injection of 200 microCi of (3H)lysine. Samples of brain and spinal cord were dissolved, and the radioactivity of acid-precipitable protein and acid-soluble fractions were determined by scintillation counting. T3 treatment influenced the general levels of incorporation of all treated groups over all days postoperation. Specific effects were observed in spinal hemisected T3-treated animals. A significant hemispheric (P less than 0.05) asymmetry was present at 3 days postoperation with the right somatomotor cortex higher in protein radioactivity than the left. In spinal cord, the area of the lesion and areas just caudal to the lesion were higher in (3H)lysine incorporation in T3-treated rats relative to controls. T3 effects appear to involve an increased sensitivity of the cells of the injured nervous system to the hormone. | Is there evidence to suggest that triiodothyronine has neuroprotective properties in traumatic brain injury? | T3 effects appear to involve an increased sensitivity of the cells of the injured nervous system to the hormone. |
Patients with deletions of the TWIST gene did not differ from those with intragenic TWIST mutations in frequency or severity of craniofacial abnormalities. However, they did distinguish themselves by the presence of many additional anomalies and diseases and--most importantly--the high frequency of mental retardation, which was borderline significant. The authors conclude that when using stringent inclusion criteria for studies of Saethre-Chotzen syndrome, patients who have a pathogenic mutation of the TWIST gene should be excluded. | Which gene is primarily associated with the Saethre-Chotzen syndrome? | The authors conclude that when using stringent inclusion criteria for studies of Saethre-Chotzen syndrome, patients who have a pathogenic mutation of the TWIST gene should be excluded. |
Bartter syndrome is an uncommon tubular disorder inherited as an autosomal recessive entity. It is associated with hypokalemic metabolic alkalosis with high renin and aldosterone plasma concentration with low or normal blood pressure. Recent studies have demonstrated genetic heterogeneity in Bartter syndrome. Mutations of two genes encoding the Na/K/2Cl cotransporter and potassium channel ROMK are responsible for clinical features of neonatal Bartter syndrome. Mutations of gen encoding the chloride channel ClC-Kb is identified as being causative for the classic Bartter syndrome. And dysfunction of Na/Cl cotransporter in the distal convoluted renal tubule is described as Gitelman syndrome. | What is the Bartter syndrome? | Bartter syndrome is an uncommon tubular disorder inherited as an autosomal recessive entity. |
Transcription-coupled repair (TCR) is a cellular process by which some forms of DNA damage are repaired more rapidly from transcribed strands of active genes than from nontranscribed strands or the overall genome. In humans, the TCR coupling factor, CSB, plays a critical role in restoring transcription following both UV-induced and oxidative DNA damage. It also contributes indirectly to the global repair of some forms of oxidative DNA damage. The Escherichia coli homolog, Mfd, is similarly required for TCR of UV-induced lesions. However, its contribution to the restoration of transcription and to global repair of oxidative damage has not been examined. Here, we report the first direct study of transcriptional recovery following UV-induced and oxidative DNA damage in E. coli. We observed that mutations in mfd or uvrA reduced the rate that transcription recovered following UV-induced damage. In contrast, no difference was detected in the rate of transcription recovery in mfd, uvrA, fpg, nth, or polB dinB umuDC mutants relative to wild-type cells following oxidative damage. mfd mutants were also fully resistant to hydrogen peroxide (H(2)O(2)) and removed oxidative lesions from the genome at rates comparable to wild-type cells. The results demonstrate that Mfd promotes the rapid recovery of gene expression following UV-induced damage in E. coli. In addition, these findings imply that Mfd may be functionally distinct from its human CSB homolog in that it does not detectably contribute to the recovery of gene expression or global repair following oxidative damage. | Which proteins act as factors that promote transcription-coupled repair in bacteria? | Transcription-coupled repair (TCR) is a cellular process by which some forms of DNA damage are repaired more rapidly from transcribed strands of active genes than from nontranscribed strands or the overall genome. In humans, the TCR coupling factor, CSB, plays a critical role in restoring transcription following both UV-induced and oxidative DNA damage. It also contributes indirectly to the global repair of some forms of oxidative DNA damage. The Escherichia coli homolog, Mfd, is similarly required for TCR of UV-induced lesions. |
The cylindromatosis tumor suppressor gene (Cyld) encodes a deubiquitinating enzyme (CYLD) with immunoregulatory function. In this study, we evaluated the role of Cyld in T cell ontogeny by generating a mouse (Cyld(Delta9)) with a thymocyte-restricted Cyld mutation that causes a C-terminal truncation of the protein and reciprocates catalytically inactive human mutations. Mutant mice had dramatically reduced single positive thymocytes and a substantial loss of peripheral T cells. The analyses of polyclonal and TCR-restricted thymocyte populations possessing the mutation revealed a significant block in positive selection and an increased occurrence of apoptosis at the double-positive stage. Interestingly, in the context of MHC class I and II restricted TCR transgenes, lack of functional CYLD caused massive deletion of thymocytes that would have been positively selected, which is consistent with an impairment of positive selection. Biochemical analysis revealed that Cyld(Delta9) thymocytes exhibit abnormally elevated basal activity of NF-kappaB and JNK. Most importantly, inactivation of NF-kappaB essential modulator fully restored the NF-kappaB activity of Cyld(Delta9) thymocytes to physiologic levels and rescued their developmental and survival defect. This study identifies a fundamental role for functional CYLD in establishing the proper threshold of activation for thymocyte selection by a mechanism dependent on NF-kappaB essential modulator. | Is the protein product of the cylindromatosis gene (CYLD) a deubiquitinating enzyme? | The cylindromatosis tumor suppressor gene (Cyld) encodes a deubiquitinating enzyme (CYLD) with immunoregulatory function. |
A previous randomized phase 2 study of hepatocellular carcinoma revealed that the c-Met inhibitor tivantinib as second-line treatment significantly prolonged progression-free survival in a subpopulation whose tumor samples highly expressed c-Met (MET-high). Accordingly, this phase 3 study was conducted to evaluate the efficacy of tivantinib as a second-line treatment for Japanese patients with MET-high hepatocellular carcinoma. This randomized, double-blind, placebo-controlled study was conducted at 60 centers in Japan. Hepatocellular carcinoma patients with one prior sorafenib treatment and those with MET-high tumor samples were eligible for inclusion. Registered patients were randomly assigned to either the tivantinib or placebo group at a 2:1 ratio and were treated with twice-a-day oral tivantinib (120 mg bid) or placebo until the discontinuation criteria were met. The primary endpoint was progression-free survival while the secondary endpoints included overall survival and safety. Between January 2014 and June 2016, 386 patients provided consent, and 195 patients were randomized to the tivantinib (n = 134) or placebo (n = 61) group. Median progression-free survival was 2.8 (95% confidence interval: 2.7-2.9) and 2.3 (1.5-2.8) mo in the tivantinib and placebo groups, respectively (hazard ratio = 0.74, 95% confidence interval: 0.52-1.04, P = .082). Median overall survival was 10.3 (95% confidence interval: 8.1-11.6) and 8.5 (6.2-11.4) mo in the tivantinib and placebo group, respectively (hazard ratio = 0.82, 95% confidence interval: 0.58-1.15). The most common tivantinib-related grade ≥3 adverse events were neutropenia (31.6%), leukocytopenia (24.8%), and anemia (12.0%). This study did not confirm the significant efficacy of tivantinib as a second-line treatment for Japanese patients with MET-high hepatocellular carcinoma. (NCT02029157). | Is tivantinib effective for MET-high hepatocellular carcinoma? | Median progression-free survival was 2.8 (95% confidence interval: 2.7-2.9) and 2.3 (1.5-2.8) mo in the tivantinib and placebo groups, respectively (hazard ratio = 0.74, 95% confidence interval: 0.52-1.04, P = .082). Median overall survival was 10.3 (95% confidence interval: 8.1-11.6) and 8.5 (6.2-11.4) mo in the tivantinib and placebo group, respectively (hazard ratio = 0.82, 95% confidence interval: 0.58-1.15). |
A homogeneous group of 214 infertile women with endometriosis treated at the Johns Hopkins Hospital from 1960 to 1979 received conservative surgery as the sole therapeutic modality. Among this group, 115 patients (54%) conceived following surgery; of these conceptions, 109 resulted in a living child. Among 49 patients with secondary infertility, the spontaneous abortion rate was reduced from 49% to 20% after conservative surgery (P less than or equal to 0.01). Three contemporary classification systems were utilized to categorize patients according to the sites and amount of endometriosis at the time of conservative surgery. Those systems suggested by Buttram (Fertil Steril 30:240, 1978) and by Kistner and coauthors (Fertil Steril 28:108, 1977) revealed differences among fecundability rates among the different categories (P less than or equal to 0.01); however, the system suggested by The American Fertility Society (AFS) (Fertil Steril 32:633, 1979) revealed significant differences only if categories were combined (mild plus moderate versus severe plus extensive, P less than or equal to 0.05). Nevertheless, the AFS system revealed that pregnancy success was significantly reduced if an ovarian endometrioma was greater than 3 cm or had ruptured (P less than or equal to 0.01). | Does surgery for ovarian endometriomas improve fertility? | Among this group, 115 patients (54%) conceived following surgery; of these conceptions, 109 resulted in a living child. |
Evans syndrome is a very rare hematologic autoimmune disease, characterized by a direct Coombs' positive hemolytic anemia and immune thrombocytopenic purpura without a known underlying etiology. The clinical course is generally chronic with frequent relapses and remissions. Evans syndrome usually is complicated by hemolytic or thrombocytopenic symptoms. This is seldom associated with thrombosis or infarction. Reported here is a case with massive hemoperitoneum because of splenic infarction with rupture, in an 18-month-old male patient with Evans syndrome, and the embolization of splenic artery. This article also carries clinical and imaging features and the review of medical literature. | List the two most important hematological features of the Evans syndrome | Evans syndrome usually is complicated by hemolytic or thrombocytopenic symptoms. |
Soon after qualification, Fortescue Fox (1858-1940) began practice in a Scottish spa where he acquired a lifelong interest in chronic disorders, especially arthritis. He worked to improve the status of spa medicine, recasting it as medical hydrology. At the start of the First World War, his interests turned to the handling of war casualties and a seminal work on physical treatment and rehabilitation was published in 1916. He set up a physical treatment clinic for damaged soldiers and co-founded a residential community where such treatment could be coupled with paid work in rural crafts. After the war Fox was a founder and president of the International League against Rheumatism and helped establish a groundbreaking outpatient clinic from which academic rheumatology in the UK developed. Yet he is not seen as a founding father of British rheumatology, having been on the losing side of an argument about the focus of the specialty. In medical rehabilitation he does have that honour. | Is medical hydrology the same as Spa therapy? | Soon after qualification, Fortescue Fox (1858-1940) began practice in a Scottish spa where he acquired a lifelong interest in chronic disorders, especially arthritis. He worked to improve the status of spa medicine, recasting it as medical hydrology |
Large intergenic noncoding RNAs (lincRNAs) are still poorly functionally characterized. We analyzed the genetic and epigenetic regulation of human lincRNA expression in the GenCord collection by using three cell types from 195 unrelated European individuals. We detected a considerable number of cis expression quantitative trait loci (cis-eQTLs) and demonstrated that the genetic regulation of lincRNA expression is independent of the regulation of neighboring protein-coding genes. lincRNAs have relatively more cis-eQTLs than do equally expressed protein-coding genes with the same exon number. lincRNA cis-eQTLs are located closer to transcription start sites (TSSs) and their effect sizes are higher than cis-eQTLs found for protein-coding genes, suggesting that lincRNA expression levels are less constrained than that of protein-coding genes. Additionally, lincRNA cis-eQTLs can influence the expression level of nearby protein-coding genes and thus could be considered as QTLs for enhancer activity. Enrichment of expressed lincRNA promoters in enhancer marks provides an additional argument for the involvement of lincRNAs in the regulation of transcription in cis. By investigating the epigenetic regulation of lincRNAs, we observed both positive and negative correlations between DNA methylation and gene expression (expression quantitative trait methylation [eQTMs]), as expected, and found that the landscapes of passive and active roles of DNA methylation in gene regulation are similar to protein-coding genes. However, lincRNA eQTMs are located closer to TSSs than are protein-coding gene eQTMs. These similarities and differences in genetic and epigenetic regulation between lincRNAs and protein-coding genes contribute to the elucidation of potential functions of lincRNAs. | How are lincRNA affecting the regulation of gene expression? | We detected a considerable number of cis expression quantitative trait loci (cis-eQTLs) and demonstrated that the genetic regulation of lincRNA expression is independent of the regulation of neighboring protein-coding genes. |
Stimulating microbial reduction of soluble U(VI) to insoluble U(IV) shows promise as a strategy for immobilizing uranium in uranium-contaminated subsurface environments. In order to learn more about which microorganisms might be involved in U(VI) reduction in situ, the changes in the microbial community when U(VI) reduction was stimulated with the addition of acetate were monitored in sediments from three different uranium-contaminated sites in the floodplain of the San Juan River in Shiprock, N.Mex. In all three sediments U(VI) reduction was accompanied by concurrent Fe(III) reduction and a dramatic enrichment of microorganisms in the family Geobacteraceae, which are known U(VI)- and Fe(III)-reducing microorganisms. At the point when U(VI) reduction and Fe(III) reduction were nearing completion, Geobacteraceae accounted for ca. 40% of the 16S ribosomal DNA (rDNA) sequences recovered from the sediments with bacterial PCR primers, whereas Geobacteraceae accounted for fewer than 5% of the 16S rDNA sequences in control sediments that were not amended with acetate and in which U(VI) and Fe(III) reduction were not stimulated. Between 55 and 65% of these Geobacteraceae sequences were most similar to sequences from Desulfuromonas species, with the remainder being most closely related to Geobacter species. Quantitative analysis of Geobacteraceae sequences with most-probable-number PCR and TaqMan analyses indicated that the number of Geobacteraceae sequences increased from 2 to 4 orders of magnitude over the course of U(VI) and Fe(III) reduction in the acetate-amended sediments from the three sites. No increase in Geobacteraceae sequences was observed in control sediments. In contrast to the predominance of Geobacteraceae sequences, no sequences related to other known Fe(III)-reducing microorganisms were detected in sediments. These results compare favorably with an increasing number of studies which have demonstrated that Geobacteraceae are important components of the microbial community in a diversity of subsurface environments in which Fe(III) reduction is an important process. The combination of these results with the finding that U(VI) reduction takes place during Fe(III) reduction and prior to sulfate reduction suggests that Geobacteraceae will be responsible for much of the Fe(III) and U(VI) reduction during uranium bioremediation in these sediments. | List bacteria that may be useful in uranium bioremediation. | Geobacteraceae |
Neurofibromatosis type 1 and Noonan syndrome are both common genetic disorders with autosomal dominant inheritance. Similarities between neurofibromatosis type 1 and Noonan syndrome have been noted for over 20 years and patients who share symptoms of both conditions are often given the diagnosis of neurofibromatosis-Noonan syndrome (NFNS). The molecular basis of these combined phenotypes was poorly understood and controversially discussed over several decades until the discovery that the syndromes are related through disturbances of the Ras pathway. We present an infant male with coarse facial features, severe supravalvar pulmonic stenosis, automated atrial tachycardia, hypertrophic cardiomyopathy, airway compression, severe neurological involvement, and multiple complications that lead to death during early infancy. The severity of clinical presentation and significant dysmorphic features suggested the possibility of a double genetic disorder in the Ras pathway instead of NFNS. Molecular analysis showed a missense mutation in exon 25 of the NF1 gene (4288A>G, p.N1430D) and a pathogenic mutation on exon 8 (922A>G, p.N308D) of the PTPN11 gene. Cardiovascular disease has been well described in patients with Noonan syndrome with PTPN11 mutations but the role of haploinsufficiency for neurofibromin in the heart development and function is not yet well understood. Our case suggests that a double genetic defect resulting in the hypersignaling of the Ras pathway may lead to complex cardiovascular abnormalities, cardiomyopathy, refractory arrhythmia, severe neurological phenotype, and early death. | Which is the genetic defect causing Neurofibromatosis type 1? | Molecular analysis showed a missense mutation in exon 25 of the NF1 gene (4288A>G, p.N1430D) |
Psychologists, quality of life and well-being researchers have grown increasingly interested in understanding the factors that are associated with human happiness. Although twin studies estimate that genetic factors account for 35-50% of the variance in human happiness, knowledge of specific genes is limited. However, recent advances in molecular genetics can now provide a window into neurobiological markers of human happiness. This investigation examines association between happiness and monoamine oxidase A (MAOA) genotype. Data were drawn from a longitudinal study of a population-based cohort, followed for three decades. In women, low expression of MAOA (MAOA-L) was related significantly to greater happiness (0.261 SD increase with one L-allele, 0.522 SD with two L-alleles, P=0.002) after adjusting for the potential effects of age, education, household income, marital status, employment status, mental disorder, physical health, relationship quality, religiosity, abuse history, recent negative life events and self-esteem use in linear regression models. In contrast, no such association was found in men. This new finding may help explain the gender difference on happiness and provide a link between MAOA and human happiness. | Is there a genetic component for happiness? | This investigation examines association between happiness and monoamine oxidase A (MAOA) genotype. |
Neuromedin U (NMU) is a neuropeptide with potent activity on smooth muscle which was isolated first from porcine spinal cord and later from other species. It is widely distributed in the gut and central nervous system. Peripheral activities of NMU include stimulation of smooth muscle, increase of blood pressure, alteration of ion transport in the gut, control of local blood flow and regulation of adrenocortical function. An NMU receptor has not been molecularly identified. Here we show that the previously described orphan G-protein-coupled receptor FM-3 (ref. 15) and a newly discovered one (FM-4) are cognate receptors for NMU. FM-3, designated NMU1R, is abundantly expressed in peripheral tissues whereas FM-4, designated NMU2R, is expressed in specific regions of the brain. NMU is expressed in the ventromedial hypothalamus in the rat brain, and its level is significantly reduced following fasting. Intracerebroventricular administration of NMU markedly suppresses food intake in rats. These findings provide a molecular basis for the biochemical activities of NMU and may indicate that NMU is involved in the central control of feeding. | What is Neuromedin U (NmU) | Neuromedin U (NMU) is a neuropeptide with potent activity on smooth muscle which was isolated first from porcine spinal cord and later from other species. |
We aimed to investigate potential synovial autoantigens in rheumatoid arthritis (RA) that could trigger the induction of B-cell autoantibodies. Total protein extract of synovial tissue obtained from seven RA patients was pooled and separated by 1-DE and 2-DE. The corresponding blots were probed with sera from RA (n = 30) and disease control samples (n = 30). Protein spots showing a sensitivity of >15% were identified by MS. 1-D immunoblots revealed one protein band with a specificity in RA of 100%, a sensitivity of 43%, which was identified as fibrinogen β chain. 2-D analysis revealed the subunits of fibrinogen, especially the β and γ chain, as the most prominent synovial autoantigens. We also identified vimentin, the Sa-antigen and carbonic anhydrase I as a potentially new synovial autoantigen. The protein patterns of these immunoreactive spots were observed as trains. The spots showing the highest autoimmune reactivity occurred at the acidic side of these trains and were recognized by anticitrullinated protein/peptide antibodies positive RA sera. Antimodified citrulline staining of these patterns confirmed protein citrullination. Therefore, PTMs such as citrullination due to alterations of peptidylarginine deiminase activity or generation of RA-specific epitopes, should be considered as a trigger in tolerance break. | List diseases where protein citrullination plays an important role. | PTMs such as citrullination due to alterations of peptidylarginine deiminase activity or generation of RA-specific epitopes, should be considered as a trigger in tolerance break. |
Formation of myelin sheaths by Schwann cells (SCs) enables rapid and efficient transmission of action potentials in peripheral axons, and disruption of myelination results in disorders that involve decreased sensory and motor functions. Given that construction of SC myelin requires high levels of lipid and protein synthesis, mitochondria, which are pivotal in cellular metabolism, may be potential regulators of the formation and maintenance of SC myelin. Supporting this notion, abnormal mitochondria are found in SCs of neuropathic peripheral nerves in both human patients and the relevant animal models. However, evidence for the importance of SC mitochondria in myelination has been limited, until recently. Several studies have recently used genetic approaches that allow SC-specific ablation of mitochondrial metabolic activity in living animals to show the critical roles of SC mitochondria in the development and maintenance of peripheral nerve axons. Here, we review current knowledge about the involvement of SC mitochondria in the formation and dysfunction of myelinated axons in the peripheral nervous system. | What is myelin? | Formation of myelin sheaths by Schwann cells (SCs) enables rapid and efficient transmission of action potentials in peripheral axons, and disruption of myelination results in disorders that involve decreased sensory and motor functions. |
Urinary incontinence imposes a significant financial burden on individuals, their families, and healthcare organizations. For individuals 65 years of age and older these costs are substantial, increasing from $8.2 billion (1984 dollars) to $16.4 billion (1993 dollars). Both of these cost-of-illness estimates, however, relied on data and factors that have changed over time. This study updates these cost estimates. The 1995 societal cost of incontinence for individuals aged 65 years and older was $26.3 billion, or $3565 per individual with urinary incontinence. Limitations, implications, and directions for future research are also discussed. | What is known about the economic cost of urinary incontinence? | The 1995 societal cost of incontinence for individuals aged 65 years and older was $26.3 billion, or $3565 per individual with urinary incontinence. |
Friedreich's ataxia (FRDA) is a genetic neurodegenerative disease that is caused by guanine-adenine-adenine (GAA) nucleotide repeat expansions in the first intron of the frataxin (FXN) gene. Although present in the intron, this mutation leads to a substantial decrease in protein expression. Currently, no effective treatment is available for FRDA, and, in addition to FXN, other targets with therapeutic potential are continuously sought. As miRNAs can regulate the expression of a broad spectrum of genes, are used as biomarkers, and can serve as therapeutic tools, we decided to identify and characterize differentially expressed miRNAs and their targets in FRDA cells compared to unaffected control (CTRL) cells. In this study, we performed an integrated miRNAseq and RNAseq analysis using the same cohort of primary FRDA and CTRL cells. The results of the transcriptome studies were supported by bioinformatic analyses and validated by qRT-PCR. miRNA interactions with target genes were assessed by luciferase assays, qRT-PCR, and immunoblotting. In silico analysis identified the FXN transcript as a target of five miRNAs upregulated in FRDA cells. Further studies confirmed that miRNA-224-5p indeed targets FXN, resulting in decreases in mRNA and protein levels. We also validated the ability of miRNA-10a-5p to bind and regulate the levels of brain-derived neurotrophic factor (BDNF), an important modulator of neuronal growth. We observed a significant decrease in the levels of miRNA-10a-5p and increase in the levels of BDNF upon correction of FRDA cells via zinc-finger nuclease (ZFN)-mediated excision of expanded GAA repeats. Our comprehensive transcriptome analyses identified miRNA-224-5p and miRNA-10a-5p as negative regulators of the FXN and BDNF expression, respectively. These results emphasize not only the importance of miRNAs in the pathogenesis of FRDA but also their potential as therapeutic targets for this disease. | What gene is mutated in Friedreich's ataxia? | Friedreich's ataxia (FRDA) is a genetic neurodegenerative disease that is caused by guanine-adenine-adenine (GAA) nucleotide repeat expansions in the first intron of the frataxin (FXN) gene. |
A number of disorders have been described to cause protein losing enteropathy (PLE) in children. Primary intestinal lymphangiectasia (PIL) is one mechanism leading to PLE. Few syndromes are associated with PIL; Hennekam syndrome (HS) is one of them. The principal treatment for PIL is a high protein, low fat diet with medium chain triglycerides supplementation. Supportive therapy includes albumin infusion. Few publications have supported the use of octreotide to diminish protein loss and minimize hypoalbuminemia seen in PIL. There are no publications on the treatment of PIL with octreotide in patients with HS. We report two children with HS and PLE in which we used octreotide to decrease intestinal protein loss. In one patient, octreotide increased serum albumin to an acceptable level without further need for albumin infusions. The other patient responded more dramatically with near normal serum albumin levels and cessation of albumin infusions. In achieving a good response to octreotide in both patients, we add to the publications supporting the use of octreotide in PIL and suggest that octreotide should be tried in patients with PIL secondary to HS. To the best of our knowledge, this is the first case report on the use of octreotide in HS-associated PIL. | Which diseases are associated with Primary intestinal lymphangiectasia (PIL)? | Few syndromes are associated with PIL; Hennekam syndrome (HS) is one of them. |
These results suggest that long-term T4 treatment after MI has beneficial effects on myocyte, arteriolar, and collagen matrix remodeling in the non-infarcted area. Most importantly, results suggest improved survival of myocytes in the peri-infarct area. | Does thyroid hormone affect cardiac remodeling ? | These results suggest that long-term T4 treatment after MI has beneficial effects on myocyte, arteriolar, and collagen matrix remodeling in the non-infarcted area. Most importantly, results suggest improved survival of myocytes in the peri-infarct area. |
Macroautophagy was thought to be an unspecific bulk degradation process. However, Ponpuak et al. (2010) show in this issue of Immunity that cytosolic proteins are selectively recruited to autophagosomes to become metabolized to bactericidal peptides. | Is macroautophagy a selective degradation process? | Macroautophagy was thought to be an unspecific bulk degradation process. |
Acute sport exercise leads to a strong stimulation of muscle tissue and a change in the organism energy demands. This study was designed to investigate the effect of oral melatonin supplementation on human physiological functions associated with acute exercise. Immune, endocrine and metabolic parameters were measured in 16 young male football players, who were divided into two groups, an experimental group (supplementation with 6 mg of melatonin administered 30 min prior to exercise) and a control group (placebo without melatonin). They performed a continuous exercise of high intensity (135 beats/min). Samples were collected 30 min before the exercise and 3, 15 and 60 min during the exercise. The results indicated that the acute sport training presented: a) increased lipid peroxidation products (MDA) in both groups, control and experimental, with levels significantly decreased in the group treated with melatonin after 15 and 60 min of high-intensity exercise, b) the total antioxidant activity (TAS) was lower in the control group than in the experimental, the latter showing significant differences at 60 min of high-intensity exercise c) the lipid profile of subjects in the experimental group showed lower triglyceride levels than the control group after 15 and 60 min of high-intensity exercise, d) immunological studies only showed, in the experimental group, an increase in IgA levels at 60 min after the exercise, and finally there were no significant differences between the groups for any of the other variables. In conclusion these results indicated that treatment with melatonin in acute sports exercise reversed oxidative stress, improved defenses and lipid metabolism, which would result in an improvement in fitness. | Which are the supplemental antioxidant in athletes? | In conclusion these results indicated that treatment with melatonin in acute sports exercise reversed oxidative stress, improved defenses and lipid metabolism, which would result in an improvement in fitness. |
Virtually all patients of the rare inflammatory eye disease birdshot chorioretinopathy (BSCR) carry the HLA-A*29:02 allele. BSCR is also associated with endoplasmic reticulum aminopeptidase 2 (ERAP2), an enzyme involved in processing HLA class I ligands, thus implicating the A*29:02 peptidome in this disease. To investigate the relationship between both risk factors we employed label-free quantitative mass spectrometry to characterize the effects of ERAP2 on the A*29:02-bound peptidome. An ERAP2-negative cell line was transduced with lentiviral constructs containing GFP-ERAP2 or GFP alone, and the A*29:02 peptidomes from both transduced cells were compared. A similar analysis was performed with two additional A*29:02-positive, ERAP1-concordant, cell lines expressing or not ERAP2. In both comparisons the presence of ERAP2 affected the following features of the A*29:02 peptidome: 1) Length, with increased amounts of peptides >9-mers, and 2) N-terminal residues, with less ERAP2-susceptible and more hydrophobic ones. The paradoxical effects on peptide length suggest that unproductive binding to ERAP2 might protect some peptides from ERAP1 over-trimming. The influence on N-terminal residues can be explained by a direct effect of ERAP2 on trimming, without ruling out and improved processing in concert with ERAP1. The alterations in the A*29:02 peptidome suggest that the association of ERAP2 with BSCR is through its effects on peptide processing. These differ from those on the ankylosing spondylitis-associated HLA-B*27. Thus, ERAP2 alters the peptidome of distinct HLA molecules as a function of their specific binding preferences, influencing different pathological outcomes in an allele-dependent way. | Is the enzyme ERAP2 associated with the disease birdshot chorioretinopathy? | BSCR is also associated with endoplasmic reticulum aminopeptidase 2 (ERAP2), an enzyme involved in processing HLA class I ligands, thus implicating the A*29:02 peptidome in this disease. |
Pain is a complex and subjective experience. Previous studies have shown that mice lacking the dopamine D3 receptor (D3RKO) exhibit hypoalgesia, indicating a role of the D3 receptor in modulation of nociception. Given that there are sex differences in pain perception, there may be differences in responses to nociceptive stimuli between male and female D3RKO mice. In the current study, we examined the role of the D3 receptor in modulating nociception in male and female D3RKO mice. Acute thermal pain was modeled by hot-plate test. This test was performed at different temperatures including 52°C, 55°C, and 58°C. The von Frey hair test was applied to evaluate mechanical pain. And persistent pain produced by peripheral tissue injury and inflammation was modeled by formalin test. In the hot-plate test, compared with wild-type (WT) mice, D3RKO mice generally exhibited longer latencies at each of the three temperatures. Specially, male D3RKO mice showed hypoalgesia compared with male WT mice when the temperature was 55°C, while for the female mice, there was a statistical difference between genotypes when the test condition was 52°C. In the von Frey hair test, both male and female D3RKO mice exhibited hypoalgesia. In the formalin test, the male D3RKO mice displayed a similar nociceptive behavior as their sex-matched WT littermates, whereas significantly depressed late-phase formalin-induced nociceptive behaviors were observed in the female mutants. These findings indicated that the D3 receptor affects nociceptive behaviors in a sex-specific manner and that its absence induces more analgesic behavior in the female knockout mice. © 2016 Wiley Periodicals, Inc. | What is the Formalin test used for? | And persistent pain produced by peripheral tissue injury and inflammation was modeled by formalin test. |
Formation of centromeric heterochromatin in fission yeast requires the combined action of chromatin modifying enzymes and small RNAs derived from centromeric transcripts. Positive feedback mechanisms that link the RNAi pathway and the Clr4/Suv39h1 histone H3K9 methyltransferase complex (Clr-C) result in requirements for H3K9 methylation for full siRNA production and for siRNA production to achieve full histone methylation. Nonetheless, it has been proposed that the Argonaute protein, Ago1, is the key initial trigger for heterochromatin assembly via its association with Dicer-independent "priRNAs." The RITS complex physically links Ago1 and the H3-K9me binding protein Chp1. Here we exploit an assay for heterochromatin assembly in which loss of silencing by deletion of RNAi or Clr-C components can be reversed by re-introduction of the deleted gene. We showed previously that a mutant version of the RITS complex (Tas3(WG)) that biochemically separates Ago1 from Chp1 and Tas3 proteins permits maintenance of heterochromatin, but prevents its formation when Clr4 is removed and re-introduced. Here we show that the block occurs with mutants in Clr-C, but not mutants in the RNAi pathway. Thus, Clr-C components, but not RNAi factors, play a more critical role in assembly when the integrity of RITS is disrupted. Consistent with previous reports, cells lacking Clr-C components completely lack H3K9me2 on centromeric DNA repeats, whereas RNAi pathway mutants accumulate low levels of H3K9me2. Further supporting the existence of RNAi-independent mechanisms for establishment of centromeric heterochromatin, overexpression of clr4(+) in clr4Δago1Δ cells results in some de novo H3K9me2 accumulation at centromeres. These findings and our observation that ago1Δ and dcr1Δ mutants display indistinguishable low levels of H3K9me2 (in contrast to a previous report) challenge the model that priRNAs trigger heterochromatin formation. Instead, our results indicate that RNAi cooperates with RNAi-independent factors in the assembly of heterochromatin. | What is the function of yeast Clr4 on chromatin? | Positive feedback mechanisms that link the RNAi pathway and the Clr4/Suv39h1 histone H3K9 methyltransferase complex (Clr-C) result in requirements for H3K9 methylation for full siRNA production and for siRNA production to achieve full histone methylation. |
Amniotic band syndrome is a well described clinical entity presenting with deformities of the limbs, thorax, craniofacial skeleton, soft tissues and umbilical cord, but it still lacks a precise definition and a coherent hypothesis for its pathogenesis. We report on a case of first trimester diagnosis of amniotic band syndrome by sonography and fetoscopy. This revealed multiple abnormalities including facial cleft, brain and limb deformities; the appearance of the amniotic cavity was that of a cobweb containing the fetus. Post-mortem examination and histopathological studies confirmed the diagnosis of amniotic band syndrome. These results may enhance the knowledge of its natural course. In addition, based on histological and newly identified ultrastructural features, we present a hypothesis which could help to explain the aetiopathogenesis of the amniotic band syndrome. | Explain amniotic band syndrome. | Amniotic band syndrome is a well described clinical entity presenting with deformities of the limbs, thorax, craniofacial skeleton, soft tissues and umbilical cord, but it still lacks a precise definition and a coherent hypothesis for its pathogenesis. We re |
Literature search was done on PubMed using the search terms 'golimumab' AND 'ulcerative colitis' from inception till March 2016. Golimumab, a fully human monoclonal antibody against TNF-α, was approved by FDA for clinical use in UC in 2013. In vitro studies showed golimumab to be better than infliximab and adalimumab in terms of affinity and neutralization of TNF-α and its conformational stability. Golimumab was found to be effective and safe in inducing and maintaining clinical remission, clinical response and mucosal healing in patients with UC in the two registration trials. Expert commentary: Although there is no difference in terms of efficacy between golimumab, infliximab and adalimumab, golimumab is better than infliximab in terms of route of administration (subcutaneous vs intravenous) and better than adalimumab in terms of frequency of dosing (4 weeks vs 2 weeks). | Is golimumab effective for ulcerative colitis? | Golimumab was found to be effective and safe in inducing and maintaining clinical remission, clinical response and mucosal healing in patients with UC in the two registration trials. |
Hepcidin is encoded as an 84 amino acid prepropeptide containing a typical N-terminal 24 amino acid endoplasmic reticulum targeting signal sequence, and a 35 amino acid proregion (pro) with a consensus furin cleavage site immediately followed by the C-terminal 25 amino acid bioactive iron-regulatory hormone (mature peptide). We performed pulse-chase studies of posttranslational processing of hepcidin in human hepatoma HepG2 cells and in primary human hepatocytes induced with bone morphogenic protein (BMP-9). In some experiments, the cells were treated with the furin protease inhibitor decanoyl-Arg-Val-Lys-Arg-chloromethylketone (CMK) or furin siRNA. In the absence of furin inhibitor, hepcidin was found to be processed in less than 1 h and secreted as a 3 kDa form reactive with anti-mature but not anti-pro antibody. In the presence of furin inhibitors or furin siRNA, a 6 kDa form reactive with both anti-pro and anti-mature antibody was rapidly secreted into the medium. Processing was not affected by inhibitors of the hypoxia inducible factor (HIF) pathway, or by treatment with 30 microM holo- or apo-transferrin. In conclusion, the hepatic prohormone convertase furin mediates the posttranslational processing of hepcidin. The proteolytic cleavage of prohepcidin to hepcidin is not regulated by iron-transferrin or the HIF pathway. | What is the connection between furin and hepcidin? | In conclusion, the hepatic prohormone convertase furin mediates the posttranslational processing of hepcidin. |