bluuebunny/crossref_metadata_2025 huggingface dataset:
Proteinase-activated receptor-2 modulates human macrophage differentiation and effector function
Authors: Steven Rachael , Crilly Anne , Lockhart John C , Ferrell William R , McInnes Iain B
Published: April 2013

Proteinase-activated receptor-2 (PAR-2) was shown to influence immune regulation; however, its role in human macrophage subset development and function has not been addressed. Here, PAR-2 expression and activation was investigated on granulocyte macrophage (GM)-CSF(M1) and macrophage (M)-CSF(M2) macrophages. In both macrophages, the PAR-2-activating peptide, SLIGKV, increased PAR-2 expression and regulated TNF-α and IL-10 secretion in a manner similar to LPS. In addition, HLA-DR on M1 cells also increased. Monocytes matured to an M1 phenotype in the presence of SLIGKV had reduced cell area, and released less TNF-α after LPS challenge compared with vehicle ( P < 0.05, n = 3). Cells matured to an M2 phenotype with SLIGKV also had a reduced cell area and made significantly more TNF-α after LPS exposure compared to vehicle ( P < 0.05, n = 3) with reduced IL-10 secretion ( P < 0.05, n = 3). Thus, PAR-2 activation on macrophage subsets regulates HLA-DR and PAR-2 surface expression, and drives cytokine production. In contrast, PAR-2 activation during M1 or M2 maturation induces altered cell morphology and skewing of phenotype, as evidenced by cytokine secretion. These data suggest a complex role for PAR-2 in macrophage biology and may have implications for macrophage-driven disease in which proteinase-rich environments can influence the immune process directly.
Mouse pyrin and HIN domain family member 1 (pyhin1) protein positively regulates LPS-induced IFN-β and NO production in macrophages
Authors: Haque Abedul , Koide Naoki , Odkhuu Erdenezaya , Tsolmongyn Bilegtsaikhan , Naiki Yoshikazu , Komatsu Takayuki , Yoshida Tomoaki , Yokochi Takashi
Published: April 2013

The pyrin and HIN-domain (PYHIN) family member1 (pyhin1) is a member of PYHIN proteins and involved in transcriptional regulation of genes important for cell cycle control, differentiation and apoptosis. The regulatory action of mouse pyhin1 on LPS-induced inflammatory response was examined. LPS augmented the pyhin1 mRNA expression in murine RAW 264.7 macrophage cells and peritoneal macrophages. The augmentation of pyhin1 mRNA expression was abolished by parthenolide, a NF-κB inhibitor. Silencing of pyhin1 with small interfering RNA reduced the production of IFN‐β and NO. However, pyhin1 silencing did not affect the production of TNF-α, IL-6, IL-10 and prostaglandin E2. Reduced IFN-β production by pyhin1 silencing caused inactivation of STAT1 and reduced expression of IRF1. Pyhin1 silencing inhibited the expression of TRAF6, TBK1 and TRIF, which trigger IFN-β production in the MyD88-independent pathway. However, pyhin1 silencing did not affect the expression of MyD88, IRAK4 and several mitogen-activated protein kinases in the MyD88-dependent pathway. Taken together, mouse pyhin1 was suggested to be a NF-κB-responsible gene in response to LPS and positively regulate LPS-induced IFN-β and NO production through up-regulating the MyD88-independent signaling pathway.
Yeast cell wall supplementation alters the metabolic responses of crossbred heifers to an endotoxin challenge
Authors: Sanchez Nicole C Burdick , Young Tanner R , Carroll Jeffery A , Corley Jimmie R , Rathmann Ryan J , Johnson Bradley J
Published: April 2013

This study examined the effect of feeding yeast cell wall (YCW) products on the metabolic responses of newly-received feedlot cattle to an endotoxin challenge. Heifers were separated into treatment groups receiving either a Control diet, YCW-A or YCW-C, and were fed for 52 d. Heifers were weighed on d 0, 14, 36, 38 and 52. On d 37 heifers were challenged i.v. with LPS [0.5 µg/kg body weight (BW)] and blood samples were collected relative to LPS challenge. Heifer BW increased from d 0 to 36 and from d 38 to 52, but was not affected by treatment. Post-LPS, glucose concentrations increased and were less in YCW-A than Control and YCW-C heifers. Pre-LPS, insulin concentrations were greater in YCW-A and YCW-C than Control heifers. Post-LPS, insulin concentrations increased with YCW-C having greater insulin than Control heifers. Pre-LPS, NEFA concentrations tended to be less in YCW-C than Control heifers. Post-LPS non-esterified fatty acids (NEFA) concentrations were less in YCW-C than Control and YCW-A heifers. Post-LPS, blood urea nitrogen (BUN) concentrations were greater in YCW-A than Control and YCW-C. These data indicate, based on NEFA and BUN data, that certain YCW products can enhance energy metabolism during an immune challenge without causing lipolysis or muscle catabolism.
Intermediate-Term Results Following First Metatarsal Cheilectomy
Authors: Bussewitz Bradly W. , Dyment Macaira M. , Hyer Christopher F.
Published: April 2013

Hallux rigidus is a term describing degenerative joint disease (DJD) to the first metatarsal phalangeal joint (MTPJ). It is the most common DJD encountered in the foot and is the second most common pathology of the great toe behind hallux valgus. The goal of a cheilectomy is to relieve pain and increase MTPJ motion. Critical evaluation of the cheilectomy must include longevity of desired results. The primary goal of this study was to determine how long a cheilectomy can be expected to last before an arthrodesis or joint destructive procedure is performed, if ever. We examined 189 cheilectomies with a mean radiographic follow-up of 235 days and mean chart review follow-up of 1184 days (3.2 years). Analysis showed 5 repeat cheilectomies, 1 interpositional arthroplasty, and only 2 arthrodeses subsequently performed. This retrospective study provides intermediate term evidence that cheilectomy is an appropriate procedure for stages 1, 2, and 3 first MTPJ DJD with reliable, lasting results.

Levels of Evidence: Therapeutic, Level III
Trends and Factors Associated with Initial and Recurrent Methicillin-Resistant Staphylococcus aureus (MRSA) Skin and Soft-Tissue Infections among HIV-Infected Persons
Authors: Vyas Kartavya J. , Shadyab Aladdin H. , Lin Chii-Dean , Crum-Cianflone Nancy F.
Published: April 2013

Background:

Factors associated with initial methicillin-resistant Staphylococcus aureus (MRSA) skin and soft-tissue infections (SSTIs) and their recurrence have not been fully elucidated among HIV-infected persons.

Methods:

We retrospectively evaluated a large cohort of HIV-infected patients from 1993 to 2010 for culture-proven MRSA SSTIs. Separate logistic regression models evaluated factors associated with initial and recurrent infections.

Results:

Of the 794 patients, 63 (8%) developed an initial infection (19.8 infections/1000 person years [PY]); risk factors included CD4 count <500 cells/mm3 and HIV RNA level ≥400 copies/mL ( P < .01), US Centers for Disease Control and Prevention (CDC) stage C versus A/B ( P < .01), and injection drug use (IDU, P < .01). In all, 27% developed recurrence (206 infections/1000 PY); risk factors included hospital admission ( P = .02). Minocycline for treatment of the initial infection was associated with an 80% decreased odds for recurrence ( P = .03).

Conclusion:

HIV control and avoidance of IDU may be useful in reducing rates of MRSA SSTIs among HIV-infected persons.
Whole-exome sequencing in adult ETP-ALL reveals a high rate of DNMT3A mutations
Authors: Neumann Martin , Heesch Sandra , Schlee Cornelia , Schwartz Stefan , Gökbuget Nicola , Hoelzer Dieter , Konstandin Nikola P. , Ksienzyk Bianka , Vosberg Sebastian , Graf Alexander , Krebs Stefan , Blum Helmut , Raff Thorsten , Brüggemann Monika , Hofmann Wolf-Karsten , Hecht Jochen , Bohlander Stefan K. , Greif Philipp A. , Baldus Claudia D.
Published: April 2013

Key Points

Exome sequencing of adult ETP-ALL reveals new recurrent mutations; in particular, DNMT3A is frequently mutated in adult ETP-ALL. More than 60% of all adult patients with ETP-ALL harbor a mutation that could potentially be targeted by a specific therapy.
Comparison of automated and manual FISH for evaluation of HER2 gene status on breast carcinoma core biopsies
Authors: Öhlschlegel Christian , Kradolfer Doris , Hell Margreth , Jochum Wolfram
Published: April 2013

Background

Positive HER2 status identifies breast carcinomas that might respond to trastuzumab treatment. Manual HER2 fluorescent in situ hybridisation (FISH) is the most readily used method to detect HER2 gene amplification which defines positive HER2 status in addition to HER2 protein overexpression. Automation of HER2 FISH may improve HER2 gene testing. The aim of our study was to evaluate an automated HER2 FISH assay for assessing the HER2 genomic status.

Methods

Core biopsies of 100 invasive breast carcinomas were analysed in parallel using the PathVysion™ HER-2 DNA Probe Kit and the Leica HER2 FISH System for BOND™. To assess inter-method agreement, concordance analysis was performed for various numerical and categorical HER2/CEP17 FISH parameters.

Results

Carcinomas with all HER2 immunohistochemical scores were included (0+: 20; 1+: 20; 2+: 30; 3+: 30). Using either HER2/CEP17 ratio >2.2 or ≥2.0 as criterion for HER2 amplification, high levels of concordance were observed between automated and manual FISH (concordance rate 96%, κ coefficient 0.92). High levels of inter-method agreement were also found for HER2 copy number, CEP17 copy number, HER2/CEP17 ratio, the percentage of carcinoma cells with HER2/CEP17 ratio >2.2, and the presence of HER2 genetic heterogeneity, HER2 clusters and CEP17 polyploidy.

Conclusions

HER2 testing using automated FISH is feasible on breast carcinoma core biopsies. Automated HER2 FISH using the Leica HER2 FISH System for BOND is a practical and efficient alternative to manual HER2 FISH in evaluating the HER2 status of primary invasive breast carcinomas.
Diesel exhaust but not ozone increases fraction of exhaled nitric oxide in a randomized controlled experimental exposure study of healthy human subjects
Authors: Barath Stefan , Mills Nicholas L , Ädelroth Ellinor , Olin Anna-Carin , Blomberg Anders
Published: April 2013

Background

Fraction of exhaled nitric oxide (FENO) is a promising non-invasive index of airway inflammation that may be used to assess respiratory effects of air pollution. We evaluated FENO as a measure of airway inflammation after controlled exposure to diesel exhaust or ozone.

Methods

Healthy volunteers were exposed to either diesel exhaust (particle concentration 300 μg/m3) and filtered air for one hour, or ozone (300 ppb) and filtered air for 75 minutes. FENO was measured in duplicate at expiratory flow rates of 10, 50, 100 and 270 mL/s before, 6 and 24 hours after each exposure.

Results

Exposure to diesel exhaust increased FENO at 6 hours compared with air at expiratory flow rates of 10 mL/s (p = 0.01) and at 50 mL/s (p = 0.011), but FENO did not differ significantly at higher flow rates. Increases in FENO following diesel exhaust were attenuated at 24 hours. Ozone did not affect FENO at any flow rate or time point.

Conclusions

Exposure to diesel exhaust, but not ozone, increased FENO concentrations in healthy subjects. Differences in the induction of airway inflammation may explain divergent responses to diesel exhaust and ozone, with implications for the use of FENO as an index of exposure to air pollution.
ZnO nanorod array-coated mesh film for the separation of water and oil
Authors: Li Hong , Li Yushan , Liu Qinzhuang
Published: April 2013

Dense and vertically aligned ZnO nanorod arrays with a large area have been fabricated successfully on the stainless steel mesh by a simple chemical vapor deposition method. The coated mesh exhibited both superoleophilic and superhydrophobic properties, even if it was not modified by low surface energy materials. The separation efficiencies were more than 97% in the filtration of water and oil. Besides, the wettability of the coated mesh was still stable after it was soaked in the corrosive solutions for 1 h. A detailed investigation showed that the coated mesh has the best superhydrophobic property when the stainless steel mesh pore size was about 75 μm.
A mutual GrabCut method to solve co-segmentation
Authors: Gao Zhisheng , Shi Peng , Karimi Hamid Reza , Pei Zheng
Published: April 2013

Co-segmentation aims at segmenting common objects from a group of images. Markov random field (MRF) has been widely used to solve co-segmentation, which introduces a global constraint to make the foreground similar to each other. However, it is difficult to minimize the new model. In this paper, we propose a new Markov random field-based co-segmentation model to solve co-segmentation problem without minimization problem. In our model, foreground similarity constraint is added into the unary term of MRF model rather than the global term, which can be minimized by graph cut method. In the model, a new energy function is designed by considering both the foreground similarity and the background consistency. Then, a mutual optimization approach is used to minimize the energy function. We test the proposed method on many pairs of images. The experimental results demonstrate the effectiveness of the proposed method.
The anatomical evaluation of the dental arches using cone beam computed tomography - an investigation of the availability of bone for placement of mini-screws
Authors: Pan Feng , Kau Chung H , Zhou Hong , Souccar Nada
Published: April 2013

Objective

To assess the amount of maxillary and mandibular inter-radicular bone mass and determine the most reliable mini-screw placement sites.

Materials and methods

Retrospective Cone Beam Computed Tomography (CBCT) images of 40 Angle Class I subjects (20 females, 20 males, aged 16 to 32) were obtained. Measurements on the buccal (BI), medial (MI) and lingual (LI) sides of the inter-radicular spaces were taken at 0, 1, 2, 3, 4, 5 mm from the cemento-enamel junction (CEJ) in an apical direction.

Results

The male and female BI scores ranged from 2.99±0.73 mm to 6.18±1.03 mm and 2.69±0.84 mm to 6.21±1.22 mm respectively. The male and female MI scores ranged from 1.36±0.38 mm to 4.50±0.99 and 1.53±0.66 to 4.77±1.99 mm respectively. LI scores ranged from 2.37±0.70 to 6.47±1.0 mm and 2.45±0.56 mm and 6.66±1.33 mm respectively. In both maxillary and mandibular arch, the inter-radicular space increased in the apical direction except for the buccal and medial inter-radicular spaces between the maxillary first and second molars.

Conclusion

The medial inter-radicular spaces are the decisive parameter for mini-screw placement. In the maxillary arch, regions between central and lateral incisors, lateral incisor and canine, first and second molars are not viable for mini-screw insertion. The residual inter-radicular regions are proper for implantation at 3 mm above the CEJ. In the mandible, the regions between incisors and canines are too narrow for mini-screw insertion and the reliable sites for mini-screws are regions between premolars, molars or first molar and second premolar at 2 mm below the CEJ.
Ki-67 labeling in canine perianal glands neoplasms: a novel approach for immunohistological diagnostic and prognostic
Authors: Pereira Rodrigo Storti , Schweigert Augusto , Melo Guilherme Dias de , Fernandes Fernando Vissani , Sueiro Felipe Augusto Ruiz , Machado Gisele Fabrino
Published: April 2013

Background

The antibody Ki-67 is a reliable and easy tool to accurately assess the growth fraction of neoplasms in humans and animals, and it has been used to predict the clinical outcome. Therefore, the aim of the present study was to investigate the immunohistochemical expression pattern of Ki-67 in normal and neoplastic perianal glands of dogs to evaluate the possible use of this proliferation marker as an ancillary method of perianal tumor diagnosis. We studied 42 cases of perianal gland neoplasms including adenomas (n = 15), epitheliomas (n = 15), and carcinomas (n = 12). As controls, 13 tissue samples from normal perianal glands were used. A Ki-67 index was established by a computer-assisted image analysis and compared with manual counting.

Results

Out of the 42 cases of perianal gland neoplasms, 34 were from males and eight from females. Recurrence was reported in 14 cases, being higher (8/12) in carcinomas. Immunostaining for Ki-67 revealed that the carcinomas showed a higher proliferation rate (9.87%) compared to groups of epitheliomas (2.66%) and adenomas (0.36%). For adenomas and epitheliomas of the perianal glands the computer-assisted counting and the manual counting gave similar results; however, only the computer-assisted image analysis was efficient to predict the perianal gland carcinoma recurrence.

Conclusion

Since there were significant differences in the number of Ki-67-positive nuclei, this marker proved to be effective in helping the classification of perianal gland neoplasms and to refine the diagnosis criteria, especially in those samples with high variation in morphology/area. Also, higher Ki-67 index is related to recurrence in cases of perianal gland carcinomas. Further, the computer-assisted image analysis proved to be a fast and reliable method to assess the Ki-67 index in perianal gland neoplasms.
Synthesis and characterization of ZnO nanostructures using palm olein as biotemplate
Authors: Ramimoghadam Donya , Hussein Mohd Zobir Bin , Taufiq-Yap Yun Hin
Published: April 2013

Background

A green approach to synthesize nanomaterials using biotemplates has been subjected to intense research due to several advantages. Palm olein as a biotemplate offers the benefits of eco-friendliness, low-cost and scale-up for large scale production. Therefore, the effect of palm olein on morphology and surface properties of ZnO nanostructures were investigated.

Results

The results indicate that palm olein as a biotemplate can be used to modify the shape and size of ZnO particles synthesized by hydrothermal method. Different morphology including flake-, flower- and three dimensional star-like structures were obtained. FTIR study indicated the reaction between carboxyl group of palm olein and zinc species had taken place. Specific surface area enhanced while no considerable change were observed in optical properties.

Conclusion

Phase-pure ZnO particles were successfully synthesized using palm olein as soft biotemplating agent by hydrothermal method. The physico-chemical properties of the resulting ZnO particles can be tuned using the ratio of palm olein to Zn cation.
Sustained release formulation of an anti-tuberculosis drug based on para-amino salicylic acid-zinc layered hydroxide nanocomposite
Authors: Saifullah Bullo , Hussein Mohd Zobir , Hussein-Al-Ali Samer Hasan , Arulselvan Palanisamy , Fakurazi Sharida
Published: April 2013

Background

Tuberculosis (TB), is caused by the bacteria, Mycobacterium tuberculosis and its a threat to humans since centuries. Depending on the type of TB, its treatment can last for 6–24 months which is a major cause for patients non-compliance and treatment failure. Many adverse effects are associated with the currently available TB medicines, and there has been no new anti-tuberculosis drug on the market for more than 50 year, as the drug development is very lengthy and budget consuming process.

Development of the biocompatible nano drug delivery systems with the ability to minimize the side effects of the drugs, protection of the drug from enzymatic degradation. And most importantly the drug delivery systems which can deliver the drug at target site would increase the therapeutic efficacy. Nanovehicles with their tendency to release the drug in a sustained manner would result in the bioavalibilty of the drugs in the body for a longer period of time and this would reduce the dosing frequency in drug administration. The biocompatible nanovehicles with the properties like sustained release of drug of the target site, protection of the drug from physio-chemical degradation, reduction in dosing frequency, and prolong bioavailability of drug in the body would result in the shortening of the treatment duration. All of these factors would improve the patient compliance with chemotherapy of TB.

Result

An anti-tuberculosis drug, 4-amino salicylic acid (4-ASA) was successfully intercalated into the interlamellae of zinc layered hydroxide (ZLH) via direct reaction with zinc oxide suspension. The X-ray diffraction patterns and FTIR analyses indicate that the molecule was successfully intercalated into the ZLH interlayer space with an average basal spacing of 24 Å. Furthermore, TGA and DTG results show that the drug 4-ASA is stabilized in the interlayers by electrostatic interaction. The release of 4-ASA from the nanocomposite was found to be in a sustained manner. The nanocomposite treated with normal 3T3 cells shows it reduces cell viability in a dose- and time-dependent manner.

Conclusions

Sustained release formulation of the nanocomposite, 4-ASA intercalated into zinc layered hydroxides, with its ease of preparation, sustained release of the active and less-toxic to the cell is a step forward for a more patient-friendly chemotherapy of Tuberculosis.
Identification of Trypanosoma cruzi Discrete Typing Units (DTUs) through the implementation of a High-Resolution Melting (HRM) genotyping assay
Authors: Higuera Sonia L , Guhl Felipe , Ramírez Juan David
Published: April 2013

Background

Chagas disease, caused by Trypanosoma cruzi, is a geographically widespread anthropozoonosis that is considered a major public health problem in Latin America. Because this parasite presents high genetic variability, a nomenclature has been adopted to classify the parasite into six discrete typing units (DTUs): TcI, TcII, TcIII, TcIV, TcV, and TcVI, which present different eco-epidemiological, clinical, and geographic associations. Currently, the available genotyping methods present a series of drawbacks that implies the need for developing new methods for characterizing T. cruzi DTU’s. The aim of this work was to genotype reference populations from T. cruzi by means of a High-Resolution Melting (HRM) genotyping assay.

To genotype the DTUs of 38 strains and 14 reference clones of T. cruzi from diverse sources, real-time PCR (qPCR) was coupled to high-resolution melting (HRM) based on the amplification of two molecular markers—the divergent domain of the 24 sα rRNA gene and the intergenic region of the mini-exon gene.

Findings

Amplification of the mini-exon gene allowed the genotyping of three distinct groups: TcI, TcII- TcIV- TcV, and TcIII-TcVI, while amplification of the 24sα gene generated non-overlapping melting temperature ranges for each DTU that were used to identify the groups in the six existing DTUs of Trypanosoma cruzi.

Conclusions

The proposed genotyping assay allowed discrimination of the six genetic groups by obtaining specific melting curves for each DTU. The application of this technique is proposed because of its specificity, sensitivity, high performance, and low cost compared with other previously described characterization methods.
Factor Inhibiting HIF-1 (FIH-1) modulates protein interactions of Apoptosis-Stimulating p53 binding Protein 2 (ASPP2)
Authors: Janke Kirsten , Brockmeier Ulf , Kuhlmann Katja , Eisenacher Martin , Nolde Jan , Meyer Helmut E. , Mairbäurl Heimo , Metzen Eric
Published: April 2013

The asparaginyl hydroxylase Factor Inhibiting HIF-1 (FIH-1) is an important suppressor of hypoxia-inducible factor (HIF) activity. Besides HIF-α, FIH-1 was previously shown to hydroxylate other substrates within a highly conserved protein interaction domain, termed the ankyrin repeat domain (ARD). However, the biological role of FIH-1-dependent ARD hydroxylation could not be clarified for any ARD containing substrate to date. The apoptosis-stimulating p53-binding protein (ASPP) family members were initially identified as highly conserved regulators of the tumour suppressor p53. In addition, ASPP2 was shown to be important for the regulation of cell polarity via interaction with partitioning defective 3 homolog (Par-3). We identified ASPP2 as a new substrate of FIH-1 by mass spectrometry while inhibitory ASPP (iASPP) was not hydroxylated. We demonstrated that ASPP2 asparagine 986 (N986) is a single hydroxylation site located within the ARD. ASPP2 protein levels and stability were not affected by depletion or inhibition of the enzyme. However, FIH-1 depletion led to impaired binding of Par-3 to ASPP2 while neither interaction between ASPP2 and p53, nor apoptosis or proliferation of the cancer cells were affected. Depletion of FIH-1 and incubation with the hydroxylase inhibitor dimethyloxalylglycine (DMOG) resulted in dislocation of ASPP2 from cell cell contacts to the cytosol. Our data thus demonstrate that protein interactions of ARD containing substrates can be modified by FIH-1 dependent hydroxylation. The large cellular pool of ARD containing proteins may imply effects of FIH-1 on a broad range of cellular functions and signalling pathways, for example in response to severe hypoxia.
Cytoplasmic localization of DGKζ exerts a protective effect against p53-mediated cytotoxicity
Authors: Tanaka Toshiaki , Okada Masashi , Hozumi Yasukazu , Tachibana Ken , Kitanaka Chifumi , Hamamoto Yoshioki , Martelli Alberto M. , Topham Matthew K. , Iino Mitsuyoshi , Goto Kaoru
Published: April 2013

The transcription factor p53 plays a crucial role in coordinating the cellular response to various stresses. Therefore, p53 protein levels and activity need to be kept under tight control. We report here that diacylglycerol kinase ζ (DGKζ) binds to p53 and modulates its function both in the cytoplasm and nucleus. DGKζ, one of the DGK family that metabolizes a lipid second messenger diacylglycerol, localizes primarily to the nucleus in various cell types. Recently, reports have described that excitotoxic stress induces DGKζ nucleocytoplasmic translocation in hippocampal neurons. In this study, we found that cytoplasmic DGKζ attenuates p53-mediated cytotoxicity against doxorubicin-induced DNA damage by facilitating cytoplasmic anchoring and degradation of p53 through a ubiquitin–proteasome system. Concomitantly, decreased levels of nuclear DGKζ engender down-regulation of p53 transcriptional activity. Consistent with these in vitro cellular experiments, DGKζ-deficient brain exhibits high levels of p53 protein after kainate-induced seizures and even under normal conditions. These findings provide novel insights into the regulation of p53 function and suggest that DGKζ serves as a sentinel to control p53 function both during normal homeostasis and in stress responses.
Cell wall stress induces alternative fungal cytokinesis and septation strategies
Authors: Walker Louise A. , Lenardon Megan D. , Preechasuth Kanya , Munro Carol A. , Gow Neil A. R.
Published: April 2013

In fungi, as with all walled organisms, cytokinesis followed by septation marks the end of the cell cycle and is essential for cell division and viability. For yeasts, the septal cross-wall comprises a ring and primary septal plate composed of chitin, and a secondary septum thickened with β(1,3)-glucan. In the human pathogen Candida albicans, chitin synthase enzyme Chs1 builds the primary septum that is surrounded by a chitin ring made by Chs3. Here we show that the lethal phenotype induced by repression of CHS1 was abrogated by stress-induced synthesis of alternative and novel septal types synthesized by other chitin synthase enzymes that have never before been implicated in septation. Chs2 and Chs8 formed a functional salvage septum, even in the absence of both Chs1 and Chs3. A second type of salvage septum formed by Chs2 in combination with Chs3 or Chs8 was proximally offset in the mother-bud neck. Chs3 alone or in combination with Chs8 formed a greatly thickened third type of salvage septum. Therefore, cell wall stress induced alternative forms of septation that rescued cell division in the absence of Chs1, demonstrating that fungi have previously unsuspected redundant strategies to enable septation and cell division to be maintained, even under potentially lethal environmental conditions.
Membrane-associated RING-CH (MARCH) 8 mediates the ubiquitination and lysosomal degradation of the transferrin receptor
Authors: Fujita Hideaki , Iwabu Yukie , Tokunaga Kenzo , Tanaka Yoshitaka
Published: April 2013

The transferrin receptor (TfR) mediates the uptake of transferrin (Tf)-bound iron from the plasma into the cells of peripheral tissues. The TfR continuously recycles between the plasma membrane (PM) and early/recycling endosomes. TfR expression is tightly controlled by intracellular iron concentration through the regulation of TfR mRNA stability. However, much less is known about the mechanism by which TfR is degraded in cells. Previously, we reported a correlation between TfR ubiquitination and its iron-induced lysosomal degradation. The identification and characterization of a specific ubiquitin ligase for TfR is important to understand the mechanism of iron homeostasis. Here, we show that membrane-associated RING-CH (MARCH) 8 ubiquitinates TfR and promotes its lysosomal degradation. Similar to other RING-type ubiquitin ligases, the RING-CH domain of MARCH8, which is located in the N-terminal cytoplasmic (CT) domain, is essential for the ubiquitination and down-regulation of TfR. MARCH8 specifically recognizes the transmembrane (TM) domain of TfR and mediates ubiquitination of its CT domain. In addition, the six amino acid sequence located in the C-terminal CT domain of MARCH8, which is highly conserved among different species, is required for the down-regulation of TfR. Finally, and most importantly, TfR expression was markedly increased by siRNA-mediated knockdown of endogenous MARCH8. These findings demonstrate that the endogenous level of MARCH8 regulates TfR protein turnover via the down-regulation and ubiquitination of TfR.
A specific subset of RabGTPases controls cell surface exposure of MT1-MMP, extracellular matrix degradation and 3D invasion of macrophages
Authors: Wiesner Christiane , Azzouzi Karim el , Linder Stefan
Published: April 2013

The matrix metalloproteinase MT1-MMP has a decisive impact on invasive cell migration in both physiological and pathological settings such as immune cell extravasation or metastasis of cancer cells. Surface-associated MT1-MMP is able to cleave components of the extracellular matrix, which is a prerequisite for proteolytic invasive migration. However, current knowledge on the molecular mechanisms that regulate MT1-MMP trafficking to and from the cell surface is limited. Here, we identify three members of the RabGTPase family, Rab5a, Rab8a, and Rab14, as critical regulators of MT1-MMP trafficking and function in primary human macrophages. Both overexpressed and endogenous forms show prominent colocalisation with MT1-MMP-positive vesicles, while expression of mutant constructs as well as siRNA-induced knockdown reveal that these RabGTPases critically regulate MT1-MMP surface exposure, contact of MT1-MMP-positive vesicles with podosomes, extracellular matrix degradation in 2D and 3D, as well as 3D proteolytic invasion of macrophages. Collectively, our results identify Rab5a, Rab8a, and Rab14 as major regulators of MT1-MMP trafficking and invasive migration of primary human macrophages, pointing to them as promising potential targets for manipulation of immune cell invasion.
Autosomal recessiveGJA1(Cx43) gene mutations cause oculodentodigital dysplasia by distinct mechanisms
Authors: Huang Tao , Shao Qing , MacDonald Andrew , Xin Li , Lorentz Robert , Bai Donglin , Laird Dale W.
Published: April 2013

Oculodentodigital dysplasia (ODDD) is mainly an autosomal dominant human disease caused by mutations in the GJA1 gene encoding the gap junction protein connexin43 (Cx43). Surprisingly, there have been two autosomal recessive mutations reported that cause ODDD; a single amino acid substitution (R76H) and a premature truncation mutation (R33X). When expressed in either gap junctional intercellular communication (GJIC)-deficient HeLa cells or Cx43-expressing NRK cells, the R76H mutant trafficked to the plasma membrane to form gap junction-like plaques while the R33X mutant remained diffusely localized throughout the cell including the nucleus. As expected, the R33X mutant failed to form functional channels. In the case of the R76H mutant, dye transfer studies in HeLa cells and electrical conductance analysis in GJIC-deficient N2a cells revealed that this mutant could form functional gap junction channels, albeit with reduced macroscopic and single channel conductance. Alexa 350 dye transfer studies further revealed that the R76H mutant had no detectable negative effect on the function of co-expressed Cx26, Cx32, Cx37 or Cx40 while the R33X mutant exhibited significant dominant or trans-dominant effects on Cx43 and Cx40 as manifested by a reduction in wild-type connexin gap junction plaques. Taken together, our results suggest that trans-dominant effect of R33X together with its complete inability to form a functional channel may explain why patients harboring this autosomal recessive R33X mutant exhibit greater disease burden than patients harboring the R76H mutant.
Fabrication of 14 different RNA nanoparticles for specific tumor targeting without accumulation in normal organs
Authors: Shu Yi , Haque Farzin , Shu Dan , Li Wei , Zhu Zhenqi , Kotb Malak , Lyubchenko Yuri , Guo Peixuan
Published: April 2013

Due to structural flexibility, RNase sensitivity, and serum instability, RNA nanoparticles with concrete shapes for in vivo application remain challenging to construct. Here we report the construction of 14 RNA nanoparticles with solid shapes for targeting cancers specifically. These RNA nanoparticles were resistant to RNase degradation, stable in serum for >36 h, and stable in vivo after systemic injection. By applying RNA nanotechnology and exemplifying with these 14 RNA nanoparticles, we have established the technology and developed “toolkits” utilizing a variety of principles to construct RNA architectures with diverse shapes and angles. The structure elements of phi29 motor pRNA were utilized for fabrication of dimers, twins, trimers, triplets, tetramers, quadruplets, pentamers, hexamers, heptamers, and other higher-order oligomers, as well as branched diverse architectures via hand-in-hand, foot-to-foot, and arm-on-arm interactions. These novel RNA nanostructures harbor resourceful functionalities for numerous applications in nanotechnology and medicine. It was found that all incorporated functional modules, such as siRNA, ribozymes, aptamers, and other functionalities, folded correctly and functioned independently within the nanoparticles. The incorporation of all functionalities was achieved prior, but not subsequent, to the assembly of the RNA nanoparticles, thus ensuring the production of homogeneous therapeutic nanoparticles. More importantly, upon systemic injection, these RNA nanoparticles targeted cancer exclusively in vivo without accumulation in normal organs and tissues. These findings open a new territory for cancer targeting and treatment. The versatility and diversity in structure and function derived from one biological RNA molecule implies immense potential concealed within the RNA nanotechnology field.
Review of Economics and Cost-Effectiveness Analyses of Anticoagulant Therapy for Stroke Prevention in Atrial Fibrillation in the US
Authors: von Schéele Birgitta , Fernandez Maria , Hogue Susan Lynn , Kwong Winghan Jacqueline
Published: April 2013

OBJECTIVE

To summarize the available evidence on the issues in health economics related to oral anticoagulation for stroke prevention in atrial fibrillation (AF) in the US.

DATA SOURCES

A literature review was performed using PubMed, EMBASE, Cochrane Library, and International Pharmaceutical Abstracts, as well as the websites of professional organizations.

STUDY SELECTION AND DATA EXTRACTION

The search was conducted according to a prespecified protocol, limiting articles to those published in English from 2001 to October 2012 and focused on the economics associated with AF and AF-related stroke in the US. Data from 27 studies were extracted and included in the review.

DATA SYNTHESIS

Strokes in patients with AF are more debilitating and have higher recurrence rates and mortality compared with strokes unrelated to AF. However, data describing the long-term cost of AF-related stroke and stroke subtypes remain limited. The costs of major gastrointestinal (GI) bleeding and intracranial bleeding related to warfarin are significant, whereas the costs of the more frequent minor GI bleeding are relatively low. Overall, the cost-effectiveness of warfarin versus aspirin or no treatment in patients with at least 1 risk factor for stroke is well established. Economic evaluations based on results from random ized controlled clinical trials generally found that new anticoagulants were a cost-effective alternative to warfarin for stroke prevention in AF. However, these cost-effectiveness results are highly sensitive to how well optimal international normalized ratio control is maintained (within target of 2.0–3.0) for warfarin and the time horizon used for analysis. Time in therapeutic range for warfarin in routine clinical practice was lower than in clinical trials, as shown by previous studies.

CONCLUSIONS

This review identified several areas of uncertainty regarding the economic benefit of anticoagulants. The generalizability of cost-effectiveness results of anticoagulant therapy in AF based on clinical trial data must be confirmed by comparative effectiveness research conducted in the real-world setting.
Characterization of Unbound Phenytoin Concentrations in Neurointensive Care Unit Patients Using a Revised Winter-Tozer Equation
Authors: Kane Sean P , Bress Adam P , Tesoro Eljim P
Published: April 2013

BACKGROUND

Prior studies examining the accuracy of the Winter-Tozer (WT) equation for correcting total phenytoin concentrations in critically ill patients have yielded conflicting results and are limited by small sample sizes and stringent exclusion criteria, which lessen external validity.

OBJECTIVE

To determine whether the traditional WT equation is appropriate in correcting total phenytoin concentrations in a large sample of patients in a neurointensive care unit (NICU) and whether a new equation may be more predictive.

METHODS

In a retrospective study, NICU patients with reports of a concurrent total and unbound phenytoin concentration and albumin level were analyzed. Two new predictive equations were generated using a revised WT equation and regression model of baseline and laboratory characteristics. Prediction error analysis using a 20% validation cohort was conducted on all 3 equations for comparison.

RESULTS

A total of 140 adults were included for data analysis, with data on 80% used for derivation and 20% as validation of all equations. The mean unbound phenytoin concentration was 1.4 μg/mL, which represented a free fraction of 10%. Most samples were collected within 24 hours of NICU admission. Multivariate regression analysis demonstrated that albumin, total phenytoin concentration, sex, and creatinine clearance were predictive of measured unbound phenytoin concentrations. The traditional WT equation significantly underpredicted true unbound phenytoin concentrations, with 32.1% of patients having a prediction error of more than 50% in the validation cohort.

CONCLUSIONS

The traditional WT equation was significantly biased in underpredicting true unbound phenytoin concentrations in neurointensive care unit patients and should not be used in this setting. Two modified equations were more accurate and precise and should be considered for use when unbound phenytoin concentrations are not readily available in an NICU population.
Effect of the Human Chorionic Gonadotropin Diet on Patient Outcomes
Authors: Goodbar Nancy H , Foushee Jaime A , Eagerton David H , Haynes Katie B , Johnson Amanda A
Published: April 2013

OBJECTIVE

To report a case of left lower extremity deep vein thrombosis (DVT) and bilateral pulmonary embolisms in a patient who initiated the human chorionic gonadotropin (HCG) diet 2 weeks prior to presentation.

CASE SUMMARY

A 64-year-old white female presented with leg swelling and shortness of breath. Lower extremity ultrasound revealed left leg DVT, and a computed tomography angiogram revealed bilateral pulmonary embolisms. A complete history and physical examination were unremarkable for any risk factors for acute thrombosis, with the exception of the initiation of the HCG diet approximately 2 weeks prior to presentation; the patient was taking 20 sublingual drops of HCG twice daily. Results of her hypercoagulable workup were negative. Upon admission, therapy was started with enoxaparin 120 mg subcutaneously twice daily and warfarin 5 mg orally once daily. According to the Naranjo probability scale, initiation of the HCG diet was a probable cause of our patient's adverse effects.

DISCUSSION

The HCG diet has very few efficacy studies and no significant safety studies associated with its use. Six relevant studies were identified for assessment of efficacy, and only 1 was associated with a significant weight reduction in the HCG diet study population. All of these studies evaluated the use of the HCG diet via injections of the hormone and significant calorie restriction, which is known as the Simeons method. Currently marketed HCG products include sublingual drops, lozenges, and pellets, but none of these methods has an evidence-based efficacy and safety standard.

CONCLUSIONS

As popularity of the HCG diet continues to increase, so do the potential adverse events associated with the management of weight loss via an unproven strategy. Patient safety information regarding this dieting strategy should be recognized by medical professionals.
Accidental Overdose of Intrathecal Cytarabine in Children
Authors: Thienprayoon Rachel , Heym Kenneth M , Pelfrey Lindsay , Bowers Daniel C
Published: April 2013

OBJECTIVE

To report 2 cases of intrathecal cytarabine overdose in children with cancer, neither of whom underwent cerebrospinal fluid (CSF) exchange per current recommendations or developed apparent toxicity related to the event.

CASE SUMMARY

A 17-year-old female with newly diagnosed acute myeloid leukemia received 177 mg of intrathecal cytarabine rather than the appropriate dose of 70 mg. She was monitored closely with no apparent toxicity from the event. A 4-year-old boy with newly diagnosed precursor B-cell acute lymphoblastic leukemia received 175 mg of intrathecal cytarabine rather than the appropriate dose of 70 mg. CSF was immediately withdrawn and intrathecal hydrocortisone was instilled for possible antiinflammatory effect. He developed no apparent toxicity from the event.

DISCUSSION

Cytarabine is an important chemotherapeutic agent in the treatment of leukemia. One case report of intrathecal cytarabine overdose was identified in the literature, which recommended CSF exchange as management. Neither child in our report underwent CSF exchange or developed apparent toxicity related to the event. Institutional changes were made in both cases to prevent similar events.

CONCLUSIONS

These cases demonstrate that measures such as CSF exchange are not uniformly required for cytarabine overdose.
High-Resolution Profiling of Fetal DNA Clearance from Maternal Plasma by Massively Parallel Sequencing
Authors: Yu Stephanie CY , Lee Shara WY , Jiang Peiyong , Leung Tak Y , Chan KC Allen , Chiu Rossa WK , Lo YM Dennis
Published: April 2013

BACKGROUND

With the advent of massively parallel sequencing (MPS), DNA analysis can now be performed in a genomewide manner. Recent studies have demonstrated the high precision of MPS for quantifying fetal DNA in maternal plasma. In addition, paired-end sequencing can be used to determine the size of each sequenced DNA fragment. We applied MPS in a high-resolution investigation of the clearance profile of circulating fetal DNA.

METHODS

Using paired-end MPS, we analyzed serial samples of maternal plasma collected from 13 women after cesarean delivery. We also studied the transrenal excretion of circulating fetal DNA in 3 of these individuals by analyzing serial urine samples collected after delivery.

RESULTS

The clearance of circulating fetal DNA occurred in 2 phases, with different kinetics. The initial rapid phase had a mean half-life of approximately 1 h, whereas the subsequent slow phase had a mean half-life of approximately 13 h. The final disappearance of circulating fetal DNA occurred at about 1 to 2 days postpartum. Although transrenal excretion was involved in the clearance of circulating fetal DNA, it was not the major route. Furthermore, we observed significant changes in the size profiles of circulating maternal DNA after delivery, but we did not observe such changes in circulating fetal DNA.

CONCLUSIONS

MPS of maternal plasma and urinary DNA permits high-resolution study of the clearance profile of circulating fetal DNA.
Endocrine effects of tobacco smoke exposure during lactation in weaned and adult male offspring
Authors: Santos-Silva A P , Oliveira E , Pinheiro C R , Santana A C , Nascimento-Saba C C , Abreu-Villaça Y , Moura E G , Lisboa P C
Published: April 2013

Children from pregnant smokers show more susceptibility to develop obesity in adult life. Previously, we failed to demonstrate a program for obesity in rat offspring only when the mothers were exposed to tobacco smoke during lactation. Here, we studied the short- and long-term effects of smoke exposure (SE) to both dams and their pups during lactation on endocrine and metabolic parameters. For this, we designed an experimental model where nursing rats and their pups were divided into two groups: SE group, exposed to smoke in a cigarette smoking machine (four times/day, from the third to the 21st day of lactation), and group, exposed to filtered air. Pups were killed at 21 and 180 days. At weaning, SE pups showed lower body weight (7%), length (5%), retroperitoneal fat mass (59%), visceral adipocyte area (60%), and higher subcutaneous adipocyte area (95%) with hypoinsulinemia (−29%), hyperthyroxinemia (59%), hypercorticosteronemia (60%), and higher adrenal catecholamine content (+58%). In adulthood, SE offspring showed higher food intake (+10%), body total fat mass (+50%), visceral fat mass (retroperitoneal: 55%; mesenteric: 67%; and epididymal: 55%), and lower subcutaneous adipocyte area (24%) with higher serum glucose (11%), leptin (85%), adiponectin (1.4-fold increase), total triiodothyronine (71%), free thyroxine (57%), TSH (36%), triglycerides (65%), VLDL cholesterol (+66%), and HDL cholesterol (91%) levels and lower corticosteronemia (41%) and adrenal catecholamine content (57%). Our present findings suggest that tobacco SE to both dams and their pups during lactation causes malnutrition in early life that programs for obesity and hormonal and metabolic disturbances in adulthood, only if the pups are submitted to the same smoke environment as the mother.