bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of anEx VivoLymph Node Explant Model for Identification of Novel Molecules Active against Leishmania major
Authors: Peniche Alex G. , Osorio Yaneth , Renslo Adam R. , Frantz Doug E. , Melby Peter C. , Travi Bruno L.
Published: October 2013

Leishmaniasis is a vector-borne zoonotic infection affecting people in tropical and subtropical regions of the world. Current treatments for cutaneous leishmaniasis are difficult to administer, toxic, expensive, and limited in effectiveness and availability. Here we describe the development and application of a medium-throughput screening approach to identify new drug candidates for cutaneous leishmaniasis using anex vivolymph nodeexplantculture (ELEC) derived from the draining lymph nodes ofLeishmania major-infected mice. The ELEC supported intracellular amastigote proliferation and contained lymph node cell populations (and their secreted products) that enabled the testing of compounds within a system that mimicked the immunopathological environment of the infected host, which is known to profoundly influence parasite replication, killing, and drug efficacy. The activity of known antileishmanial drugs in the ELEC system was similar to the activity measured in peritoneal macrophages infectedin vitrowithL. major. Using the ELEC system, we screened a collection of 334 compounds, some of which we had demonstrated previously to be active againstL. donovani, and identified 119 hits, 85% of which were confirmed to be active by determination of the 50% effective concentration (EC50). We found 24 compounds (7%) that had aninvitrotherapeuticindex (IVTI; 50% cytotoxic/effective concentration [CC50]/EC50) > 100; 19 of the compounds had an EC50below 1 μM. According to PubChem searchs, 17 of those compounds had not previously been reported to be active againstLeishmania. We expect that this novel method will help to accelerate discovery of new drug candidates for treatment of cutaneous leishmaniasis.
Optimization of Pyrrolamides as Mycobacterial GyrB ATPase Inhibitors: Structure-Activity Relationship and
In Vivo
Efficacy in a Mouse Model of Tuberculosis
Authors: P Shahul Hameed , Solapure Suresh , Mukherjee Kakoli , Nandi Vrinda , Waterson David , Shandil Radha , Balganesh Meenakshi , Sambandamurthy Vasan K. , Raichurkar Anand Kumar , Deshpande Abhijeet , Ghosh Anirban , Awasthy Disha , Shanbhag Gajanan , Sheikh Gulebahar , McMiken Helen , Puttur Jayashree , Reddy Jitendar , Werngren Jim , Read Jon , Kumar Mahesh , R Manjunatha , Chinnapattu Murugan , Madhavapeddi Prashanti , Manjrekar Praveena , Basu Reetobrata , Gaonkar Sheshagiri , Sharma Sreevalli , Hoffner Sven , Humnabadkar Vaishali , Subbulakshmi Venkita , Panduga Vijender
Published: October 2013

Moxifloxacin has shown excellent activity against drug-sensitive as well as drug-resistant tuberculosis (TB), thus confirming DNA gyrase as a clinically validated target for discovering novel anti-TB agents. We have identified novel inhibitors in the pyrrolamide class which kill
Mycobacterium tuberculosis
through inhibition of ATPase activity catalyzed by the GyrB domain of DNA gyrase. A homology model of the
M. tuberculosis
H37Rv GyrB domain was used for deciphering the structure-activity relationship and binding interactions of inhibitors with mycobacterial GyrB enzyme. Proposed binding interactions were later confirmed through cocrystal structure studies with the
Mycobacterium smegmatis
GyrB ATPase domain. The most potent compound in this series inhibited supercoiling activity of DNA gyrase with a 50% inhibitory concentration (IC
50
) of <5 nM, an MIC of 0.03 μg/ml against
M. tuberculosis
H37Rv, and an MIC
90
of <0.25 μg/ml against 99 drug-resistant clinical isolates of
M. tuberculosis
. The frequency of isolating spontaneous resistant mutants was ∼10
−6
to 10
−8
, and the point mutation mapped to the
M. tuberculosis
GyrB domain (Ser208 Ala), thus confirming its mode of action. The best compound tested for
in vivo
efficacy in the mouse model showed a 1.1-log reduction in lung CFU in the acute model and a 0.7-log reduction in the chronic model. This class of GyrB inhibitors could be developed as novel anti-TB agents.
Insulin Treatment Modulates the Host Immune System To Enhance Pseudomonas aeruginosa Wound Biofilms
Authors: Watters Chase , Everett Jake A. , Haley Cecily , Clinton Allie , Rumbaugh Kendra P.
Published: October 2013

Diabetes affects 25.8 million people in the United States, or 8.3% of the population, and these numbers are even higher in developing countries. Diabetic patients are more susceptible to the development of chronic wounds with debilitating bacterial infections than nondiabetics. Previously, we compared the ability of the opportunistic pathogen
Pseudomonas aeruginosa
to cause biofilm-associated infections in chronic wounds of diabetic and nondiabetic mice (C. Watters, K. DeLeon, U. Trivedi, J. A. Griswold, M. Lyte, K. J. Hampel, M. J. Wargo, and K. P. Rumbaugh, Med. Microbiol. Immunol.
202:
131–141, 2013). Unexpectedly, we observed that insulin-treated diabetic mice had significantly more biofilm in their wounds, which correlated with higher antibiotic tolerance. Here, we investigated whether insulin treatment modulates the diabetic immune system to favor
P. aeruginosa
biofilm formation. Utilizing a murine chronic wound model, we found that DNA protected
P. aeruginosa
in the wounds of insulin-treated diabetic mice from antibiotic treatment. We also observed increased numbers of neutrophils, reduced numbers of macrophages, and increased cell death in the wounds of diabetic mice on insulin therapy. Taken together, these data suggest that high levels of lysed neutrophils in the wounds of diabetic mice on insulin, combined with fewer macrophages to remove the cellular debris, contribute to increased DNA levels, which enhance
P. aeruginosa
biofilms.
Brucella melitensis T Cell Epitope Recognition in Humans with Brucellosis in Peru
Authors: Cannella Anthony P. , Arlehamn Cecilia S. Lindestam , Sidney John , Patra Kailash P. , Torres Katherine , Tsolis Renee M. , Liang Li , Felgner Philip L. , Saito Mayuko , Gotuzzo Eduardo , Gilman Robert H. , Sette Alessandro , Vinetz Joseph M.
Published: October 2013

Brucella melitensis
, one of the causative agents of human brucellosis, causes acute, chronic, and relapsing infection. While T cell immunity in brucellosis has been extensively studied in mice, no recognized human T cell epitopes that might provide new approaches to classifying and prognosticating
B. melitensis
infection have ever been delineated. Twenty-seven pools of 500 major histocompatibility complex class II (MHC-II) restricted peptides were created by computational prediction of promiscuous MHC-II CD4
+
T cell derived from the top 50 proteins recognized by IgG in human sera on a genome level
B. melitensis
protein microarray. Gamma interferon (IFN-γ) and interleukin-5 (IL-5) enzyme-linked immunospot (ELISPOT) analyses were used to quantify and compare Th1 and Th2 responses of leukapheresis-obtained peripheral blood mononuclear cells from Peruvian subjects cured after acute infection (
n
= 9) and from patients who relapsed (
n
= 5). Four peptide epitopes derived from 3
B. melitensis
proteins (BMEI 1330, a DegP/HtrA protease; BMEII 0029, type IV secretion system component VirB5; and BMEII 0691, a predicted periplasmic binding protein of a peptide transport system) were found repeatedly to produce significant IFN-γ ELISPOT responses in both acute-infection and relapsing patients; none of the peptides distinguished the patient groups. IL-5 responses against the panel of peptides were insignificant. These experiments are the first to systematically identify
B. melitensis
MHC-II-restricted CD4
+
T cell epitopes recognized by the human immune response, with the potential for new approaches to brucellosis diagnostics and understanding the immunopathogenesis related to this intracellular pathogen.
New Frontiers in Type III Secretion Biology: the Chlamydia Perspective
Authors: Mueller K. E. , Plano G. V. , Fields K. A.
Published: October 2013

Members of the order
Chlamydiales
comprise a group of exquisitely evolved parasites of eukaryotic hosts that extends from single-celled amoeba to mammals. The most notable are human pathogens and include the agent of oculogenital disease
Chlamydia trachomatis
, the respiratory pathogen
C. pneumoniae
, and the zoonotic agent
C. psittaci
. All of these species are obligate intracellular bacteria that develop within parasitophorous vesicles termed inclusions. This demanding lifestyle necessitates orchestrated entry into nonphagocytic cells, creation of a privileged intracellular niche, and subversion of potent host defenses. All chlamydial genomes contain the coding capacity for a nonflagellar type III secretion system, and this mechanism has arisen as an essential contributor to chlamydial virulence. The emergence of tractable approaches to the genetic manipulation of chlamydiae raises the possibility of explosive progress in understanding this important contributor to chlamydial pathogenesis. This minireview considers challenges and recent advances that have revealed how chlamydiae have maintained conserved aspects of T3S while exploiting diversification to yield a system that exerts a fundamental role in the unique biology of
Chlamydia
species.
Cross-Reactive Immune Responses as Primary Drivers of Malaria Chronicity
Authors: Klein Eili Y. , Graham Andrea L. , Llinás Manuel , Levin Simon
Published: October 2013

The within-host dynamics of an infection with the malaria parasite
Plasmodium falciparum
are the result of a complex interplay between the host immune system and parasite. Continual variation of the
P. falciparum
erythrocyte membrane protein (PfEMP1) antigens displayed on the surface of infected red blood cells enables the parasite to evade the immune system and prolong infection. Despite the importance of antigenic variation in generating the dynamics of infection, our understanding of the mechanisms by which antigenic variation generates long-term chronic infections is still limited. We developed a model to examine the role of cross-reactivity in generating infection dynamics that are comparable to those of experimental infections. The hybrid computational model we developed is attuned to the biology of malaria by mixing discrete replication events, which mimics the synchrony of parasite replication and invasion, with continuous interaction with the immune system. Using simulations, we evaluated the dynamics of a single malaria infection over time. We then examined three major mechanisms by which the dynamics of a malaria infection can be structured: cross-reactivity of the immune response to PfEMP1, differences in parasite clearance rates, and heterogeneity in the rate at which antigens switch. The results of our simulations demonstrate that cross-reactive immune responses play a primary role in generating the dynamics observed in experimentally untreated infections and in lengthening the period of infection. Importantly, we also find that it is the primary response to the initially expressed PfEMP1, or small subset thereof, that structures the cascading cross-immune dynamics and allows for elongation of the infection.
MBL2Variations and Malaria Susceptibility in Indian Populations
Authors: Jha Aditya Nath , Sundaravadivel Pandarisamy , Singh Vipin Kumar , Pati Sudhanshu S. , Patra Pradeep K. , Kremsner Peter G. , Velavan Thirumalaisamy P. , Singh Lalji , Thangaraj Kumarasamy
Published: October 2013

Human mannose-binding lectin (MBL) encoded by theMBL2gene is a pattern recognition protein and has been associated with many infectious diseases, including malaria. We sought to investigate the contribution of functionalMBL2gene variations toPlasmodium falciparummalaria in well-defined cases and in matched controls. We resequenced the 8.7 kb of the entireMBL2gene in 434 individuals clinically classified with malaria from regions of India where malaria is endemic. The study cohort included 176 patients with severe malaria, 101 patients with mild malaria, and 157 ethnically matched asymptomatic individuals. In addition, 830 individuals from 32 socially, linguistically, and geographically diverse endogamous populations of India were investigated for the distribution of functionalMBL2variants. TheMBL2 −221C(X) allelic variant is associated with increased risk of malaria (mild malaria odds ratio [OR] = 1.9, correctedPvalue [PCorr] = 0.0036; severe malaria OR = 1.6,PCorr= 0.02). The exon1 variantsMBL2*B(severe malaria OR = 2.1,PCorr= 0.036; mild versus severe malaria OR = 2.5,PCorr= 0.039) andMBL2*C(mild versus severe malaria OR = 5.4,PCorr= 0.045) increased the odds of having malaria. The exon1MBL2*D/*B/*Cvariant increased the risk for severe malaria (OR = 3.4,PCorr= 0.000045). The frequencies of low MBL haplotypes were significantly higher in severe malaria (14.2%) compared to mild malaria (7.9%) and asymptomatic (3.8%). TheMBL2*LYPAhaplotypes confer protection, whereasMBL2*LXPAincreases the malaria risk. Our findings in Indian populations demonstrate thatMBL2functional variants are strongly associated with malaria and infection severity.
Protein Antigens Increase the Protective Efficacy of a Capsule-Based Vaccine against Staphylococcus aureus in a Rat Model of Osteomyelitis
Authors: Lattar Santiago M. , Noto Llana Mariángeles , Denoël Philippe , Germain Sophie , Buzzola Fernanda R. , Lee Jean C. , Sordelli Daniel O.
Published: October 2013

Staphylococcus aureus
is an invasive bacterial pathogen, and antibiotic resistance has impeded adequate control of infections caused by this microbe. Moreover, efforts to prevent human infections with single-component
S. aureus
vaccines have failed. In this study, we evaluated the protective efficacy in rats of vaccines containing both
S. aureus
capsular polysaccharides (CPs) and proteins. The serotypes 5 CP (CP5) and 8 CP (CP8) were conjugated to tetanus toxoid and administered to rats alone or together with domain A of clumping factor A (ClfA) or genetically detoxified alpha-toxin (dHla). The vaccines were delivered according to a preventive or a therapeutic regimen, and their protective efficacy was evaluated in a rat model of osteomyelitis. Addition of dHla (but not ClfA) to the CP5 or CP8 vaccine induced reductions in bacterial load and bone morphological changes compared with immunization with either conjugate vaccine alone. Both the prophylactic and therapeutic regimens were protective. Immunization with dHla together with a pneumococcal conjugate vaccine used as a control did not reduce staphylococcal osteomyelitis. The emergence of unencapsulated or small-colony variants during infection was negligible and similar for all of the vaccine groups. In conclusion, addition of dHla to a CP5 or CP8 conjugate vaccine enhanced its efficacy against
S. aureus
osteomyelitis, indicating that the inclusion of multiple antigens will likely enhance the efficacy of vaccines against both chronic and acute forms of staphylococcal disease.
Hemoglobin Receptor Protein from Porphyromonas gingivalis Induces Interleukin-8 Production in Human Gingival Epithelial Cells through Stimulation of the Mitogen-Activated Protein Kinase and NF-κB Signal Transduction Pathways
Authors: Fujita Yuki , Nakayama Masaaki , Naito Mariko , Yamachika Eiki , Inoue Tetsuyoshi , Nakayama Koji , Iida Seiji , Ohara Naoya
Published: October 2013

Periodontitis is an inflammatory disease of polymicrobial origin affecting the tissues supporting the tooth. The oral anaerobic bacteriumPorphyromonas gingivalis, which is implicated as an important pathogen for chronic periodontitis, triggers a series of host inflammatory responses that promote the destruction of periodontal tissues. Among the virulence factors ofP. gingivalis, hemoglobin receptor protein (HbR) is a major protein found in culture supernatants. In this study, we investigated the roles of HbR in the production of inflammatory mediators. We found that HbR induced interleukin-8 (IL-8) production in the human gingival epithelial cell line Ca9-22. p38 mitogen-activated protein kinase (MAPK) and extracellular signal-related kinase 1/2 (Erk1/2) were activated in HbR-stimulated Ca9-22 cells. Inhibitors of p38 MAPK (SB203580) and Erk1/2 (PD98059) blocked HbR-induced IL-8 production. Additionally, HbR stimulated the translocation of NF-κB-p65 to the nucleus, consistent with enhancement of IL-8 expression by activation of the NF-κB pathway. In addition, small interfering RNA (siRNA) targeting activating transcription factor 2 (ATF-2) or cyclic AMP-response element-binding protein (CREB) inhibited HbR-induced IL-8 production. Moreover, pretreatment with SB203580 and PD98059 reduced HbR-induced phosphorylation of CREB and ATF-2, respectively. Combined pretreatment with an inhibitor of NF-κB (BAY11-7082) and SB203580 was more efficient in inhibiting the ability of HbR to induce IL-8 production than pretreatment with either BAY11-7082 or SB203580 alone. Thus, in Ca9-22 cells, the direct activation of p38 MAPK and Erk1/2 by HbR caused the activation of the transcription factors ATF-2, CREB, and NF-κB, thus resulting in the induction of IL-8 production.
Hypoglycaemic haemiparesis
Authors: Kirresh Othman , Kamara Achmed , Samadian Samad
Published: October 2013

Hypoglycaemic haemiparesis (HH) is an uncommon but important presentation to the emergency department, and it often mimics stroke and is therefore frequently misdiagnosed by clinicians. The mechanism of haemiparesis is not fully understood. This case outlines a diabetic elderly woman, who had been having frequent hypoglycaemic episodes and presented to paramedics with hypoglycaemia associated with a right-sided haemiparesis. She was immediately transferred to the local stroke centre after presenting to the emergency department. CT and MRI did not fit in with her presenting neurology. Her weakness resolved, after normoglycaemia was achieved with dextrose infusion; however, she was reported to be more sleepy and drowsy than usual. After extensive and costly investigations during her prolonged inpatient stay, her unifying diagnosis was an HH which triggered of a hypoactive delirium.
Primary presentation of chronic calcific pancreatitis with massive unilateral pleural effusion
Authors: Naha Kushal , Dasari Sowjanya , Vivek G , Hande Manjunath , Acharya Vasudev
Published: October 2013

We described a 45-year-old previously healthy man presenting with progressively worsening breathlessness for 10 days. Physical examination was suggestive of a left-sided pleural effusion. A chest X-ray was confirmatory. Analysis of aspirated fluid showed a lymphocytic exudate with grossly elevated amylase and lipase levels. CT revealed chronic calcific pancreatitis as the underlying cause of effusion. Retrospective questioning failed to identify classical symptoms of chronic pancreatitis including abdominal pain and steatorrhoea. The patient was managed with intercostal drainage and supportive care. Although unusual, chronic pancreatitis should be kept as a differential diagnosis in patients with unilateral exudative pleural effusion. Elevated fluid levels of amylase and lipase are useful clues to this uncommon diagnosis.
Transient bradycardia induced by thiopentone sodium: a unique challenge in the management of refractory status epilepticus
Authors: Sharma Sushma , Nair Pradeep P , Murgai Aditya , Selvaraj Raja J
Published: October 2013

Thiopentone sodium is one of the important drugs in the armamentarium for terminating refractory status epilepticus, a neurological emergency. We report a case of thiopentone-related bradycardia during the management of the new onset refractory status epilepticus in a young man, which was circumvented by prophylactic insertion of temporary pacemaker while thiopentone infusion was continued. A systematic approach was employed to manage the status epilepticus, including infusion of thiamine and glucose followed by antiepileptic drugs. The patient was ventilated and infused with lorazepam, phenytoin, sodium valproate, levetiracetam and midazolam followed by thiopentone sodium. With the introduction of thiopentone the seizures could be controlled but the patient developed severe bradycardia and junctional rhythm. The bradycardia disappeared when thiopentone was withdrawn and reappeared when the drug was reintroduced. Propofol infusion was tried with no respite in seizures. Later thiopentone sodium was reintroduced after inserting temporary cardiac pacemaker. Seizure was controlled and patient was weaned off the ventilator.
Medical management of Captured Persons
Authors: Simpson Robin G , Wilson D , Tuck J J
Published: October 2013

In most conflicts there is the potential that there will be Captured Persons (CPERS) whose medical care is the responsibility of the capturing army. The standard of this care should be to the same standard as that afforded to one's own troops. However the medical practicalities of maintaining such standards can be difficult. This article reviews the practicalities of the medical care of CPERS as part of the UK deployment in Afghanistan on Operation HERRICK.
Widespread declines in woodland caribou (Rangifer tarandus caribou) continue in Alberta
Authors: Hervieux D. , Hebblewhite M. , DeCesare N.J. , Russell M. , Smith K. , Robertson S. , Boutin S.
Published: October 2013

Nowhere across Canada is the continued persistence of woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) more uncertain than in Alberta due to widespread industrial development. A recent Government of Canada critical habitat review determined that habitat conditions within all Alberta boreal ecotype caribou ranges are unlikely or very unlikely to allow for self-sustaining caribou populations. This habitat-based assessment was based only indirectly on empirical population trends. Here, we estimated empirical population trend and growth rate (λ) for 13 of Alberta’s 16 remaining woodland caribou populations (plus one adjacent population from Saskatchewan) from 1994 to 2012 using demographic monitoring of adult female survival and calf recruitment. We captured and radio-collared a total of 1337 adult female caribou in 14 populations and estimated the mean annual adult female survival across all populations as 0.851. We conducted 158 late-winter calf recruitment surveys across the 14 populations classifying 20 872 caribou and estimated mean recruitment of 0.154 calves/cow (i.e., 0.077 female calves/cow). We then combined annual estimates of adult female survival and female calf recruitment within each population in a simple age-structured population model to estimate population trend. Annual population growth rate across caribou populations averaged 0.918, and was significantly declining, λ < 1.0, for 10 of the 14 caribou populations. Our results confirm that woodland caribou are declining rapidly (with a realized decline of approximately 50% every 8 years) across Alberta, and support conclusions from previous habitat-based assessments that the population viability of caribou is currently compromised, supporting development and implementation of recovery actions to reverse trends.
Environmental factors influencing immigration behaviour of the invasive earthworm Lumbricus terrestris
Authors: McTavish Michael J. , Basiliko Nathan , Sackett Tara E.
Published: October 2013

Despite the ecological threats posed to northeastern North American forests by the invasive earthworm Lumbricus terrestris L., 1758 (Oligochaeta: Lumbricidae), the dispersal behaviour of this organism is poorly understood. This study investigated how environmental conditions influence the immigration behaviour of L. terrestris. Experimental mesocosms were used to test for differences in burrow establishment depending on leaf-litter type (sugar maple (Acer saccharum Marsh.) or white pine (Pinus strobus L.)) or the background population density of conspecifics (0, 25, or 100 m−2). Choice chambers were used to test for selection between habitat conditions. Video recording was used to measure the latency between introduction and establishment. A significantly greater proportion of individuals established burrows in the presence of maple over pine litter, although this preference did not result in a significant difference in latency. For higher population density treatments, the time since establishment of the background population of conspecifics had a significant effect on earthworm habitat selection, with an increasing preference for the high-density habitat over time. Population density had a significant effect on latency, with greater latency under low-density conditions. These results suggest that L. terrestris detects differences in litter type and conspecific population density and modifies its immigration behaviour accordingly. Findings may be useful in predicting and responding to future dispersal patterns of this invader.
Optical Metabolic Imaging Identifies Glycolytic Levels, Subtypes, and Early-Treatment Response in Breast Cancer
Authors: Walsh Alex J. , Cook Rebecca S. , Manning H. Charles , Hicks Donna J. , Lafontant Alec , Arteaga Carlos L. , Skala Melissa C.
Published: October 2013

Abnormal cellular metabolism is a hallmark of cancer, yet there is an absence of quantitative methods to dynamically image this powerful cellular function. Optical metabolic imaging (OMI) is a noninvasive, high-resolution, quantitative tool for monitoring cellular metabolism. OMI probes the fluorescence intensities and lifetimes of the autofluorescent metabolic coenzymes reduced NADH and flavin adenine dinucleotide. We confirm that OMI correlates with cellular glycolytic levels across a panel of human breast cell lines using standard assays of cellular rates of glucose uptake and lactate secretion (P < 0.05, r = 0.89). In addition, OMI resolves differences in the basal metabolic activity of untransformed from malignant breast cells (P < 0.05) and between breast cancer subtypes (P < 0.05), defined by estrogen receptor and/or HER2 expression or absence. In vivo OMI is sensitive to metabolic changes induced by inhibition of HER2 with the antibody trastuzumab (herceptin) in HER2-overexpressing human breast cancer xenografts in mice. This response was confirmed with tumor growth curves and stains for Ki67 and cleaved caspase-3. OMI resolved trastuzumab-induced changes in cellular metabolism in vivo as early as 48 hours posttreatment (P < 0.05), whereas fluorodeoxyglucose-positron emission tomography did not resolve any changes with trastuzumab up to 12 days posttreatment (P > 0.05). In addition, OMI resolved cellular subpopulations of differing response in vivo that are critical for investigating drug resistance mechanisms. Importantly, OMI endpoints remained unchanged with trastuzumab treatment in trastuzumab-resistant xenografts (P > 0.05). OMI has significant implications for rapid cellular-level assessment of metabolic response to molecular expression and drug action, which would greatly accelerate drug development studies. Cancer Res; 73(20); 6164–74. ©2013 AACR.
Exploration of Genome-Wide Circulating MicroRNA in Hepatocellular Carcinoma: MiR-483-5p as a Potential Biomarker
Authors: Shen Jing , Wang Antai , Wang Qiao , Gurvich Irina , Siegel Abby B. , Remotti Helen , Santella Regina M.
Published: October 2013

Background: MicroRNAs (miRNA) are abundant in the circulation and play a central role in diverse biologic processes; they may be useful for early diagnosis of hepatocellular carcinoma.

Methods: We conducted a two-phase, case–control study (20 pairs for the discovery set and 49 pairs for the validation set) to test the hypothesis that genome-wide dysregulation of circulating miRNAs differentiates hepatocellular carcinoma cases from controls. Taqman low-density arrays were used to examine genome-wide miRNA expression for the discovery set, and quantitative real-time PCR was used to validate candidate miRNAs for both discovery and validation sets.

Results: Sixty-six miRNAs were found to be significantly overexpressed in plasma of hepatocellular carcinoma cases compared with controls after adjusting for false discovery rate (P < 0.05). A volcano plot indicated that seven miRNAs had greater than 2-fold case–control differences with P < 0.01. Four significant miRNAs (miR-150, miR-30c, miR-483-5p, and miR-520b) detectable in all samples with varied expression levels were further validated in a validation set. MiR-483-5p was statistically significantly overexpressed in hepatocellular carcinoma cases compared with controls (3.20 vs. 0.82, P < 0.0001). Hepatocellular carcinoma risk factors and clinic-pathological characteristics did not influence miR-483-5p expression. The combination of plasma miR-483-5p level and hepatitis C virus status can significantly differentiate hepatocellular carcinoma cases from controls with an area under the curve of 0.908 (P < 0.0001). The sensitivity and specificity were, respectively, 75.5% and 89.8%.

Conclusions: These preliminary results suggest the importance of dysregulated circulating miR-483-5p as a potential hepatocellular carcinoma biomarker.

Impact: Confirmation of aberrant expression of miR-483-5p in a large prospective hepatocellular carcinoma study will provide support for its application to hepatocellular carcinoma detection. Cancer Epidemiol Biomarkers Prev; 22(12); 2364–73. ©2013 AACR.
Body Mass Index and Microsatellite Instability in Colorectal Cancer: A Population-based Study
Authors: Hoffmeister Michael , Bläker Hendrik , Kloor Matthias , Roth Wilfried , Toth Csaba , Herpel Esther , Frank Bernd , Schirmacher Peter , Chang-Claude Jenny , Brenner Hermann
Published: October 2013

Background: Previous studies reported a positive association of body mass index (BMI) with microsatellite-stable (MSS) but not with microsatellite-instable (MSI-high) colorectal cancer. However, information from population-based studies conducted in representative age groups is so far limited.

Methods: We conducted a population-based case–control study (DACHS) in Southern Germany, including 1,215 patients with incident colorectal cancer and 1,891 matched controls with no upper age limit. Information on risk factors of colorectal cancer was obtained in standardized interviews. Microsatellite instability was analyzed using a mononucleotide marker panel.

Results: Median age among cases was 69 years, and 115 cases were classified MSI-high (9.5%). In multivariate analyses, BMI was positively associated with both risk of MSI-high colorectal cancer [per 5 kg/m2: OR, 1.71; 95% confidence interval (CI), 1.35–2.17] and risk of MSS colorectal cancer (OR, 1.20; 95% CI, 1.07–1.33). The association with MSI-high colorectal cancer was limited to women (OR, 2.04; 95% CI, 1.50–2.77; P interaction = 0.02) and most pronounced among ever users of postmenopausal hormone replacement therapy (OR, 4.68; 95% CI, 2.36–9.30; P interaction = 0.01). In case-only analyses, BMI was more strongly associated with MSI-high colorectal cancer than with MSS colorectal cancer among women (OR, 1.84; 95% CI, 1.13–1.82; P interaction = 0.01).

Conclusions: This population-based study confirms previous findings of increased risk of MSS colorectal cancer with obesity between both sexes and suggests that overweight and obesity may also be associated with increased risk of MSI-high colorectal cancer among women.

Impact: These findings extend available data on the association of BMI and microsatellite instability in colorectal cancer and may suggest a link between overweight and obesity with sporadic MSI-high colorectal cancer in women. Cancer Epidemiol Biomarkers Prev; 22(12); 2303–11. ©2013 AACR.
Apigenin Sensitizes Colon Cancer Cells to Antitumor Activity of ABT-263
Authors: Shao Huanjie , Jing Kai , Mahmoud Esraa , Huang Haihong , Fang Xianjun , Yu Chunrong
Published: October 2013

Apigenin is an edible plant-derived flavonoid that shows modest antitumor activities in vitro and in vivo. Apigenin treatment resulted in cell growth arrest and apoptosis in various types of tumors by modulating several signaling pathways. In the present study, we evaluated interactions between apigenin and ABT-263 in colon cancer cells. We observed a synergistic effect between apigenin and ABT-263 on apoptosis of colon cancer cells. ABT-263 alone induced limited cell death while upregulating expression of Mcl-1, a potential mechanism for the acquired resistance to ABT-263. The presence of apigenin antagonized ABT-263–induced Mcl-1 upregulation and dramatically enhanced ABT-263–induced cell death. Meanwhile, apigenin suppressed AKT and ERK activation. Inactivation of either AKT or ERK by lentivirus-transduced shRNA or treatment with specific small-molecule inhibitors of these pathways enhanced ABT-263–induced cell death, mirroring the effect of apigenin. Moreover, the combination response was associated with upregulation of Bim and activation of Bax. Downregulation of Bax eliminated the synergistic effect of apigenin and ABT-263 on cell death. Xenograft studies in SCID mice showed that the combined treatment with apigenin and ABT-263 inhibited tumor growth by up to 70% without obvious adverse effects, while either agent only inhibited around 30%. Our results demonstrate a novel strategy to enhance ABT-263–induced antitumor activity in human colon cancer cells by apigenin via inhibition of the Mcl-1, AKT, and ERK prosurvival regulators. Mol Cancer Ther; 12(12); 2640–50. ©2013 AACR.
Neuropsychological Outcome after Deep Brain Stimulation in the Ventral Capsule/Ventral Striatum for Highly Refractory Obsessive-Compulsive Disorder or Major Depression
Authors: Kubu Cynthia S. , Malone Donald A. , Chelune Gordon , Malloy Paul , Rezai Ali R. , Frazier Tom , Machado Andre , Rasmussen Steven , Friehs Gerhard , Greenberg Benjamin D.
Published: October 2013

Background: Deep brain stimulation (DBS) has shown promise as a treatment for severe, highly treatment-refractory obsessive-compulsive disorder (OCD) or major depressive disorder (MDD). We describe the neuropsychological outcome in 21 patients (10 OCD and 11 MDD) who received DBS in the anterior limb of the internal capsule/ventral striatum (VC/VS). Methods: All patients completed a preoperative and postoperative neuropsychological battery. Average duration of DBS stimulation was 8.91 months (SD = 4.63) at the time of follow-up testing. Data were analyzed using practice-effect-corrected change scores. Results: No significant cognitive declines were seen. There were significant improvements in prose passage recall after chronic DBS. The cognitive improvements were not related to change in severity of OCD, depression or global impairment. Conclusions: This preliminary study suggests that VC/VS DBS does not result in cognitive declines. The observations that verbal memory improved are consistent with current theories on the role of the VS in the memory, but require replication in larger studies.
Safety and Efficacy of Motor Mapping Utilizing Short Pulse Train Direct Cortical Stimulation
Authors: Tate Matthew C. , Guo LanJun , McEvoy Jennifer , Chang Edward F.
Published: October 2013

Background/Aims: A major goal of intracranial surgery is to maximize resection while minimizing neurological morbidity, particularly motor dysfunction. Direct cortical stimulation (DCS) is a common intraoperative adjunct used to identify functional motor cortex. In this study, we report on the safety/efficacy of short pulse train DCS (direct cortical stimulation motor-evoked potential, dcMEP) for motor mapping and monitoring during intracranial surgery. Methods: A retrospective analysis of 29 patients undergoing elective craniotomy for lesions near the motor cortex was performed. dcMEP mapping (40-120 V, 500-1,000 Hz, 5-9 pulses/s, 1- to 3-ms interstimulus interval, monopolar, 50-μs pulse width) was performed either alone (n = 29) or in addition to standard DCS (n = 6). Outcome measures were positive MEPs and the presence of seizures during stimulation. dcMEP-based continuous corticospinal tract (CST) monitoring was also performed. Changes in stimulation threshold and new postoperative neurological deficits were recorded. Results: dcMEP mapping success was 96% and was not affected by preoperative motor status. Intraoperative seizure rates for dcMEP were 3% and were not related to preoperative seizure status. CST monitoring success rate was 96%, and changes in stimulation threshold were predictive of new permanent motor deficits. Conclusions: dcMEP is an effective method for mapping motor function and may prove useful for continuous CST monitoring.
Clevidipine Rapidly and Safely Reduces Blood Pressure in Acute Intracerebral Hemorrhage: The ACCELERATE Trial
Authors: Graffagnino Carmelo , Bergese Sergio , Love James , Schneider Dietmar , Lazaridis Christos , LaPointe Marc , Lee Kiwon , Lynch Gwendolyn , Hu Ming-yi , Williams Gregory C.
Published: October 2013

Background: Intracerebral hemorrhage (ICH) causes 10-15% of primary strokes, with mortality related to hematoma volume. Blood pressure (BP) reduction may attenuate hematoma expansion. ACCELERATE (the Evaluation of Patients with Acute Hypertension and Intracerebral Hemorrhage with Intravenous Clevidipine Treatment) is a pilot study representing the first evaluation of safety and efficacy of intravenous clevidipine for the rapid treatment of hypertension in ICH patients. Methods: ICH patients with a systolic BP (SBP) >160 mm Hg who present within 6 h (n = 27) or 12 h (n = 10) of symptoms were prospectively enrolled, treated with open-label clevidipine until SBP ≤160 mm Hg was achieved and then titrated to keep target SBP between 140-160 mm Hg. Results: A total of 35 patients with baseline median Glasgow Coma Scale score of 12, median NIH Stroke Scale score of 14, mean SBP of 186 mm Hg and a mean time from onset of symptoms of 5.5 h received clevidipine. Median time to achieve SBP target range was 5.5 min. All patients achieved target SBP within 30 min; 96.9% achieved target SBP with clevidipine monotherapy. CT scans showed minimal hematoma volume change for the overall population (median change 0.01 ml, -2.9%). Mild/moderate hypotension was reported in 3 patients and resolved with dose reduction or drug discontinuation. Conclusion: Clevidipine monotherapy was effective and safe for rapid BP reduction in this cohort of critically ill ICH patients. Overall, patients showed minimal hematoma expansion with BP reduction, suggesting that rapid BP control with clevidipine may have a beneficial impact on hematoma expansion and warrants further investigation.
Implementing Conventional Zamorano Dujovny Frames versus Individually Manufactured microTargeting™ Platforms - A Comparative Study on Deep Brain Stimulation in Parkinson Patients
Authors: Winkler Dirk , Hammer Niels , Oehlwein Christian , Schwarz Johannes , Strecker Karl , Fritzsch Dominik , Meixensberger Jürgen
Published: October 2013

Background and Objectives: Individually manufactured microTargeting™ platforms (MT) provide a novel generation of stereotactic systems based on preoperatively implanted bone markers and screws. The feasibility and reliability of these frames were evaluated for bilateral deep brain stimulation (DBS) in patients with idiopathic Parkinson's disease (IPD). Surgical and clinical results were compared to conventional Zamorano Dujovny frames (ZD) in this prospective study. Materials and Methods: Twenty-six IPD patients undergoing surgery for DBS were divided into 2 groups. In group I, electrode implantation was accomplished using conventional ZD. Group II underwent electrode implantation using MT. Microrecording and macrostimulation were performed and surgery time was measured. The clinical outcome was determined using the Unified Parkinson's Disease Rating Scale Part III (UPDRS III) and L-dopa-equivalent doses for a 12-month follow-up postoperatively. Results: Clinical evaluation confirmed comparable outcomes for both targeting procedures and electrode positioning. Surgical time was lower in group II than in group I. Significant improvements were determined for both groups in UPDRS III and L-dopa-equivalent dose. Conclusions: Both systems allow for reliable and safe neurosurgical procedures, yielding comparable clinical results. MT improved handling and automatic adjustment of frame coordinates. Surgery time was reduced markedly compared to conventional frames.
Relationship between Changes in Plasma Leptin Concentrations and Plasminogen Activator Inhibitor-1 in Obese Prepubertal Children after Nine Months of Treatment
Authors: Valle Jiménez Miguel , Martos Rosario , Morales Rosario M. , Valle Rosario , Cañete María Dolores , Urbano M. Mar , Bermudo Francisco , Cañete Ramón
Published: October 2013

Background/Aims: The metabolic syndrome (MS) is associated with insulin resistance (IR), inappropriate fibrinolysis and high plasma leptin concentrations. The aim of this study was to quantify fibrinolysis and MS-related variables in obese prepubertal children and to evaluate changes in these variables as a result of improved body mass index (BMI), IR and leptin levels following 9 months of treatment. Methods: The homeostasis model assessment for insulin resistance (HOMA-IR), leptin, plasminogen activator inhibitor-1 (PAI-1) and lipid profile were studied at baseline in obese (n = 50) and nonobese children (n = 50), and after 9 months of treatment in obese children. Results: In the cross-sectional study the mean values for insulin, HOMA-IR, triglycerides, leptin and PAI-1 were significantly higher in obese children than in controls. High-density lipoprotein cholesterol (HDLc) and apolipoprotein A-1 were significantly lower. In the longitudinal study, after 9 months, children with lowered BMI standard deviation score displayed a significant decrease in insulin, HOMA-IR, PAI-1, leptin and triglyceride levels, and an increase in HDLc. Only leptin proved to be an independent predictive factor for changes in PAI-1 (p = 0.010). Conclusion: Obesity-linked disorders appear in obese children prior to puberty; these disorders can be improved by decreasing BMI. Changes in leptin levels were found to independently predict changes in PAI-1 in obese children and can help to diagnose complications associated with the obesity.
Nystagmus-Based Approach to Vertebrobasilar Stroke Presenting as Vertigo without Initial Neurologic Signs
Authors: Kim Min-Beom , Boo Sung Hyun , Ban Jae Ho
Published: October 2013

Background: We aimed to investigate the clinical courses and common nystagmus of isolated vertigo patients with vertebrobasilar stroke. Methods: The patients who presented with isolated acute spontaneous vertigo with spontaneous nystagmus (acute vestibular syndrome) at the Emergency Department were retrospectively analyzed. They were referred to the Otolaryngology Department due to the absence of neurologic signs or even of imaging abnormalities after the initial examination at the Emergency Department. Various clinical features, including presenting symptoms, delayed neurologic signs, the site of infarction, and videonystagmographic (VNG) findings were analyzed. Results: Of the 468 cases of acute vestibular syndrome, 23 (4.9%) cases of radiologically proven vertebrobasilar stroke were identified. Of the 23 patients, 17 (74%) showed aggravation of vertigo or delayed neurologic signs during the admission. In the analysis of VNG, 11 (48%) cases of direction-changing gaze-evoked nystagmus, 7 (30%) cases of fixation failure in the caloric test, 6 (27%) cases of periodic alternating nystagmus, and 4 (17%) cases of atypical head-shaking nystagmus were presented. Stroke occurred in the cerebellum (n = 18, 78%), medulla (n = 4, 17%), and pons (n = 1, 4%). Conclusion: In the early stage of vertebrobasilar stroke, an accurate diagnosis was difficult in the Emergency Department even though a radiologic study was performed, but various VNG abnormalities and delayed neurologic signs could help to diagnose whether the origin is central or not.
Risk of Vascular Events after Nondisabling Small and Large Vessel Cerebral Ischemia
Authors: Achterberg S. , Pruissen D.M.O. , Kappelle L.J. , Algra A. ,   for the SMART Study Group
Published: October 2013

Background: Small- and large-vessel disease (SVD and LVD, respectively) might have a different pathogenesis and prognosis but the long-term risk of death and recurrent stroke appears to be similar in previous studies. In this study, we investigated the long-term vascular prognosis of patients with LVD and SVD in a large cohort of well-documented patients. Methods: We included 971 patients with transient ischemic attack (TIA) or nondisabling ischemic stroke of atherosclerotic origin referred to a university hospital in the Netherlands between 1994 and 2005 and followed them for the occurrence of vascular events or death. The primary outcome was a composite of stroke, myocardial infarction and vascular death, whichever happened first. Classification of SVD/LVD was primarily based on brain imaging. We used regression analyses to generate hazard ratios (HRs) with 95% confidence intervals (CIs). Sensitivity analyses were performed in subsets of the population, i.e. patients with subtype classification based on imaging, excluding TIA patients, first-ever stroke patients and LVD patients without a symptomatic carotid stenosis. Results: During a mean follow-up of 6.3 years, new vascular events occurred in 56 of 312 SVD patients (3.3%/year) and in 128 of 659 LVD patients (2.9%/year). These were ischemic strokes in 33 of the 56 events in SVD patients (2.0%/year) and 54 of the 128 events in LVD patients (1.2%/year). The corresponding age- and sex-adjusted HR for all new vascular events for LVD versus SVD was 0.76 (95% CI 0.56-1.05) for the total follow-up period. When this risk was split into early risk (<1 year) and late risk (>1 year), it was not significantly different for the 1-year risk of vascular events (HR 1.04, 95% CI 0.57-1.91); however, after 1 year of follow-up, LVD patients had fewer outcome events compared with SVD patients (HR 0.66, 95% CI 0.46-0.96). For ischemic strokes, the overall HR was 0.60 (95% CI 0.39-0.94). As with the primary outcome, here also the 1-year risk was not significantly different from >1-year risk (HR 1.31, 95% CI 0.62-2.81, and HR 0.36, 95% CI 0.21-0.63, respectively). The sensitivity analyses showed virtually the same results. Conclusion: In patients with nondisabling cerebrovascular disease, we found, despite no differences at baseline in terms of vascular risk factors, a better long-term prognosis for patients with LVD for all vascular events, especially for recurrent strokes. Our observations support a different pathogenesis in SVD and LVD patients, and optimal prevention is indicated for patients with what was formerly regarded as ‘benign' SVD stroke.