3,240 research outputs found
Recommended from our members
National Institute of Allergy and Infectious Diseases workshop report: "Chlamydia vaccines: The way forward".
Chlamydia trachomatis (Ct), an intracellular pathogen, is the most common bacterial sexually transmitted infection. In addition to acute cervicitis and urethritis, Ct can lead to serious sequelae of significant public health burden including pelvic inflammatory disease (PID) and infertility. Ct control efforts have not resulted in desired outcomes such as reduced incidence and reinfection, and this highlights the need for the development of an effective Ct vaccine. To this end, NIAID organized a workshop to consider the current status of Ct vaccine research and address critical questions in Ct vaccine design and clinical testing. Topics included the goal(s) of a vaccine and the feasibility of achieving these goals, animal models of infection including mouse and nonhuman primate (NHP) models, and correlates of protection to guide vaccine design. Decades of research have provided both whole cell-based and subunit vaccine candidates for development. At least one is currently in clinical development and efforts now need to be directed toward further development of the most attractive candidates. Overall, the discussions and presentations from the workshop highlighted optimism about the current status of Ct vaccine research and detailed the remaining gaps and questions needed to move vaccines forward
The role of the novel Th17 cytokine IL-26 in intestinal inflammation
Background and aims: Interleukin 26 (IL-26), a novel IL-10-like cytokine without a murine homologue, is expressed in T helper 1 (Th1) and Th17 cells. Currently, its function in human disease is completely unknown. The aim of this study was to analyse its role in intestinal inflammation.Methods: Expression studies were performed by reverse transcription-PCR (RT-PCR), quantitative PCR, western blot and immunohistochemistry. Signal transduction was analysed by western blot experiments and ELISA. Cell proliferation was measured by MTS (3-(4,5-dimethylthiazol-2-yl)-5-(carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. IL-26 serum levels were determined by an immunoluminometric assay (ILMA).Results: All examined intestinal epithelial cell (IEC) lines express both IL-26 receptor subunits IL-20R1 and IL-10R2. IL-26 activates extracellular signal-related kinase (ERK)-1/2 and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) mitogen-activated protein (MAP) kinases, Akt and signal transducers and activators of transcription (STAT) 1/3. IL-26 stimulation increases the mRNA expression of proinflammatory cytokines but decreases cell proliferation. In inflamed colonic lesions of patients with Crohn's disease, an elevated IL-26 mRNA expression was found that correlated highly with the IL-8 and IL-22 expression. Immunohistochemical analysis demonstrated IL-26 protein expression in colonic T cells including Th17 cells expressing the orphan nuclear receptor ROR\textgreekgt, with an increased number of colonic IL-26-expressing cells in active Crohn's disease.Conclusion: Intestinal cells express the functional IL-26 receptor complex. IL-26 modulates IEC proliferation and proinflammatory gene expression and its expression is upregulated in active Crohn's disease, indicating a role for this cytokine system in the innate host cell response during intestinal inflammation. For the first time, IL-26 expression is demonstrated in colonic ROR\textgreekgt-expressing Th17 cells in situ, supporting a role for this cell type in the pathogenesis of Crohn's disease
Cell cycle progression or translation control is not essential for vesicular stomatitis virus oncolysis of hepatocellular carcinoma.
The intrinsic oncolytic specificity of vesicular stomatitis virus (VSV) is currently being exploited to develop alternative therapeutic strategies for hepatocellular carcinoma (HCC). Identifying key regulators in diverse transduction pathways that define VSV oncolysis in cancer cells represents a fundamental prerequisite to engineering more effective oncolytic viral vectors and adjusting combination therapies. After having identified defects in the signalling cascade of type I interferon induction, responsible for attenuated antiviral responses in human HCC cell lines, we have now investigated the role of cell proliferation and translation initiation. Cell cycle progression and translation initiation factors eIF4E and eIF2Bepsilon have been recently identified as key regulators of VSV permissiveness in T-lymphocytes and immortalized mouse embryonic fibroblasts, respectively. Here, we show that in HCC, decrease of cell proliferation by cell cycle inhibitors or siRNA-mediated reduction of G(1) cyclin-dependent kinase activities (CDK4) or cyclin D1 protein expression, do not significantly alter viral growth. Additionally, we demonstrate that translation initiation factors eIF4E and eIF2Bepsilon are negligible in sustaining VSV replication in HCC. Taken together, these results indicate that cellular proliferation and the initiation phase of cellular protein synthesis are not essential for successful VSV oncolysis of HCC. Moreover, our observations indicate the importance of cell-type specificity for VSV oncolysis, an important aspect to be considered in virotherapy applications in the future
Development of a Disposable Gold Electrodes-Based Sensor for Electrochemical Measurements of cDNA Hybridization
AbstractThis work deals with the development of a disposable electrochemical biosensor for the speciïŹc detection of short DNA sequences. The sensor is an amperometric transducer with three planar electrodes, comprising a working, a counter and a pseudo-reference electrode, all made of a gold layer over a polycarbonate substrate. For the development of the genosensor, the working electrode was modiïŹed using thiol-tethered 33-mer DNA probe by chemisorptions, in a concentration range from 0.1 ÎŒM to 5 ÎŒM. Immobilization of ssDNA on gold surface was monitored with electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) in Fe(CN)64â/13â and Ruthenium(II)/(III) solutions. The time dependence of ssDNA probe immobilization was also studied. The hybridization detection is then compared with EIS and DPV measurements
Heat Sensing Receptor TRPV1 Is a Mediator of Thermotaxis in Human Spermatozoa
The molecular bases of sperm thermotaxis, the temperature-oriented cell motility, are currently under investigation. Thermal perception relies on a subclass of the transient receptor potential [TRP] channels, whose member TRPV1 is acknowledged as the heat sensing receptor. Here we investigated the involvement of TRPV1 in human sperm thermotaxis. We obtained semen samples from 16 normozoospermic subjects attending an infertility survey programme, testis biopsies from 6 patients with testicular germ cell cancer and testis fine needle aspirates from 6 patients with obstructive azoospermia undergoing assisted reproductive technologies. Expression of TRPV1 mRNA was assessed by RT-PCR. Protein expression of TRPV1 was determined by western blot, flow cytometry and immunofluorescence. Sperm motility was assessed by Sperm Class Analyser. Acrosome reaction, apoptosis and intracellular-Ca2+ content were assessed by flow cytometry. We found that TRPV1 mRNA and protein were highly expressed in the testis, in both Sertoli cells and germ-line cells. Moreover, compared to no-gradient controls at 31°C or 37°C (Ctrl 31°C and Ctrl 37°C respectively), sperm migration towards a temperature gradient of 31-37°C (T gradient) in non-capacitated conditions selected a higher number of cells (14,9 ± 4,2Ă106 cells T gradient vs 5,1± 0,3Ă106 cells Ctrl 31°C and 5,71±0,74Ă106 cells Ctrl 37°C; P = 0,039). Capacitation amplified the migrating capability towards the T gradient. Sperms migrated towards the T gradient showed enriched levels of both TRPV1 protein and mRNA. In addition, sperm cells were able to migrate toward a gradient of capsaicin, a specific agonist of TRPV1, whilst capsazepine, a specific agonist of TRPV1, blocked this effect. Finally, capsazepine severely blunted migration towards T gradient without abolishing. These results suggest that TRPV1 may represent a facilitating mediator of sperm thermotaxis
Supersymmetric AdS_3 solutions of type IIB supergravity
For every positively curved Kahler-Einstein manifold in four dimensions we
construct an infinite family of supersymmetric solutions of type IIB
supergravity. The solutions are warped products of AdS_3 with a compact
seven-dimensional manifold and have non-vanishing five-form flux. Via the
AdS/CFT correspondence, the solutions are dual to two-dimensional conformal
field theories with (2,0) supersymmetry. The corresponding central charges are
rational numbers.Comment: Dedicated to Rafael Sorkin in celebration of his 60th birthday; 5
pages, latex. v2, typos corrected, to appear in PR
Histological analysis of thrombi retrieved after acute ischemic stroke from large vessel occlusion: from research to clinical practice
Emergent reperfusion therapies have improved acute ischemic stroke prognosis, but many patients are still bound to bad clinical outcome, probably because of our incomplete knowledge of its pathophysiology. Thanks to mechanical thrombectomy, occluding material is available for histological analysis. Several studies investigated the possible relationship between thrombus composition and clinical, procedural, and radiological variables of acute ischemic stroke. The potential value of thrombus analysis as a tool for clinical practice and research is still not defined, as data from the literature are heterogeneous and sometimes conflicting. We propose a review of the existing literature regarding histological analysis of thrombi in acute ischemic stroke. We classified articles on clot composition according to the clinical variable explored in each study. We first distinguished articles about etiology, procedural, and radiological variables, and then we performed a subclassification for each group. This review could help both in the interpretation of thrombus analysis in clinical practice and in its usage for future researc
Utility of the QT interval in predicting outcomes in patients presenting to the emergency department with chest pain.
OBJECTIVES: The aim of this study was to investigate whether prolongation of the heart rate-corrected QT interval (QTc) is an independent risk factor for predicting future acute coronary syndrome (ACS) occurrence or mortality in patients with at least one cardiac risk factor presenting with chest pain to the emergency department (ED).
METHODS: This is a single-center, retrospective study of patients presenting with chest pain to the ED of Einstein Medical Center, Philadelphia, between 2011 and 2012. Proportional hazards models were used to calculate hazard ratios (HRs) for occurrence of ACS or death within 1 year. Kaplan-Meier curves were used to determine the time to event for QTc low (\u3c460 \u3ems) versus QTc high (â„460âms) groups.
RESULTS: A total of 595 patients met the inclusion criteria. Older age, hypertension, diabetes mellitus, and hyperlipidemia were more common in the QTc high group. Patients in the QTc high group were more likely to experience subsequent ACS or death (HR 8.12, 95% confidence interval 4.00-16.72), even after adjusting for traditional cardiac risk factors (HR 7.68, 95% confidence interval 3.57-16.61).
CONCLUSION: QTc prolongation at ED presentation with chest pain and at least one cardiac risk factor predicts subsequent ACS and death
Direct versus indirect treatment for preschool children who stutter: The RESTART randomized trial
Objective Stuttering is a common childhood disorder. There is limited high quality evidence regarding options for best treatment. The aim of the study was to compare the effectiveness of direct treatment with indirect treatment in preschool children who stutter. Methods In this multicenter randomized controlled trial with an 18 month follow-up, preschool children who stutter who were referred for treatment were randomized to direct treatment (Lidcombe Program; n = 99) or indirect treatment (RESTART-DCM treatment; n = 100). Main inclusion criteria were age 3-6 years, â„ 3% syllables stuttered (%SS), and time since onset â„ 6 months. The primary outcome was the percentage of non-stuttering children at 18 months. Secondary outcomes included stuttering frequency (%SS), stuttering severity ratings by the parents and therapist, severity rating by the child, health-related quality of life, emotional and behavioral problems, and speech attitude. Results Percentage of non-stuttering children for direct treatment was 76.5% (65/85) versus 71.4% (65/91) for indirect treatment (Odds Ratio (OR), 0.6; 95% CI, 0.1-2.4, p = .42). At 3 months, children treated by direct treatment showed a greater decline in %SS (significant interaction time x therapy: ÎČ = -1.89; t(282.82) = -2.807, p = .005). At 18 months, stuttering frequency was 1.2% (SD 2.1) for direct treatment and 1.5% (SD 2.1) for indirect treatment. Direct treatment had slightly better scores on most other secondary outcome measures, but no differences between treatment approaches were significant. Conclusions Direct treatment decreased stuttering more quickly during the first three months of treatment. At 18 months, however, clinical outcomes for direct and indirect treatment were comparable. These results imply that at 18 months post treatment onset, both treatments are roughly equal in treating developmental stuttering in ways that surpass expectations of natural recovery. Follow-up data are needed to confirm these findings in the longer term
- âŠ