THYMOL TEMPERS As (III) AND Hg (II) CAUSED HYPERCONTRACTILITY BY SIMILAR PATHWAYS IN ISOLATED AORTIC AND TRACHEAL RINGS

Objective: Thymol is known to cause smooth muscle relaxation, possibly by inhibition of Ca2+influx, release or loss of its sensitivity. It is, however, also reported to be a strong antioxidant in several other systems. In this study, we investigate other possible pathways of thymol caused relaxation of aortic and tracheal segments by using specific blockers, and explore it as potential ameliorator of arsenic and mercury caused hyper contraction.Methods: Male Wistar rats were used in all experiments. Aorta/trachea was carefully removed, cleaned, and cut into 2-mm thick rings. Isometric contractions were measured using organ bath system. One-way analysis of variance (ANOVA) and Student's t-test were used for statistical analyses. P<0.05 was considered significant.Results: In pollutant unexposed aortic and tracheal segments, thymol is found to inhibit contractions through quenching of reactive oxygen species (ROS) in addition to its previously reported effects on Ca2+movements. Equal effectiveness in absence and presence of NG-nitro-L-arginine methyl ester (L-NAME) indicates that nitric oxide (NO) has no significant role in the thymol caused relaxation.Conclusion: In both muscle types, thymol is found to be an effective ameliorator of As (III) and Hg (II) caused hyper contraction, at low concentrations; it acts by inhibiting the Ca2+influx whereas at high concentration, it acts by blocking Ca2+influx and neutralizing ROS.Â

Detection of mutations in gyrB using denaturing high performance liquid chromatography (DHPLC) among Salmonella enterica serovar Typhi and Paratyphi A

Background:- Fluoroquinolone resistance is mediated by mutations in the quinolone-resistance determining region (QRDR) of the topoisomerase genes. Denaturing high performance liquid chromatography (DHPLC) was evaluated for detection of clinically important mutations in gyrB among Salmonella. Method:- S. Typhi and S. ParatyphiA characterised for mutation in QRDR of gyrA, parC and parE were studied for mutation in gyrB by DHPLC and validated by sequencing. Result:- The DHPLC analysis was able to resolve the test mutant from isolates with wild type gyrB and distinguished mutants from other mutant by peak profile and shift in retention time. Three sequence variants were detected at codon 464, and a novel mutation Ser→Thr was also detected. gyrB mutation was associated with non classical quinolone resistance (NALS-CIPDS) in 34 isolates of S. Typhi only and was distinct from classical quinolone resistance associated with gyrA mutations (NALR-CIPDS). Conclusion: DHPLC is effective for the detection of mutation and can reduce the need forsequencing to detect clinically significant gyrB mutations.

Transcription factor AP-1 in esophageal squamous cell carcinoma: Alterations in activity and expression during Human Papillomavirus infection

<p>Abstract</p> <p>Background</p> <p>Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer-related deaths in Jammu and Kashmir (J&K) region of India. A substantial proportion of esophageal carcinoma is associated with infection of high-risk HPV type 16 and HPV18, the oncogenic expression of which is controlled by host cell transcription factor Activator Protein-1 (AP-1). We, therefore, have investigated the role of DNA binding and expression pattern of AP-1 in esophageal cancer with or without HPV infection.</p> <p>Methods</p> <p>Seventy five histopathologically-confirmed esophageal cancer and an equal number of corresponding adjacent normal tissue biopsies from Kashmir were analyzed for HPV infection, DNA binding activity and expression of AP-1 family of proteins by PCR, gel shift assay and immunoblotting respectively.</p> <p>Results</p> <p>A high DNA binding activity and elevated expression of AP-1 proteins were observed in esophageal cancer, which differed between HPV positive (19%) and HPV negative (81%) carcinomas. While JunB, c-Fos and Fra-1 were the major contributors to AP-1 binding activity in HPV negative cases, Fra-1 was completely absent in HPV16 positive cancers. Comparison of AP-1 family proteins demonstrated high expression of JunD and c-Fos in HPV positive tumors, but interestingly, Fra-1 expression was extremely low or nil in these tumor tissues.</p> <p>Conclusion</p> <p>Differential AP-1 binding activity and expression of its specific proteins between HPV - positive and HPV - negative cases indicate that AP-1 may play an important role during HPV-induced esophageal carcinogenesis.</p

Strengthening of antioxidant defense by Azadirachta indica in alloxan-diabetic rat tissues

Background: Azadirachta indica has been reported to correct altered glycaemia in diabetes. Objective: The aqueous extract of A. indica leaf and bark has been evaluated for its effect on antioxidant status of alloxan diabetic rats and compared with insulin treatment. Materials and Methods: The oral effective dose of A. indica leaf (500 mg/kg body weight) and A. indica bark (100 mg/kg body weight) were given once daily for 21 days to separate groups of diabetic rats. At the end of the experimental period blood glucose level and activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G-6-PD), and membrane lipid peroxidation were determined in different fractions of liver and kidney tissues. Results: Diabetic rats showed high blood glucose (P<0.01), increased level of malondialdehyde (P<0.05) and a significant decrease in the activity of antioxidant enzymes. Treatment with insulin, A. indica leaf extract (AILE), and A. indica bark extract (AIBE) restored the above altered parameters close to the control ones. Conclusions: Both AILE and AIBE were found significantly effective in reducing hyperglycemia-induced oxidative stress. The findings suggest further investigations for the possible use of A. indica as alternative medicine to prevent long-term complications of diabetes

Interferons Horizon Therapeutics

Interferons (IFNs) are a family of multi-functional proteins, called cytokines, that are produced by immune cells such as leukocytes, natural killer (NK) cells, macrophages, fibroblasts, and epithelial cells. The minute amount of these α-helical glycoproteins, produced by mammalian cells, are firm components of the innate arm of the immune system providing rapid and broad protection against numerous types of invading pathogens. Interferons, from their discovery in the 19th century, have always held out a promise of important clinical utility first as an antiviral agent and more recently holding anti-inflammatory and regenerative effects for treating various neurological diseases such as multiple sclerosis, encephalopathies, Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), etc. IFNs elicit anti-viral and anti-inflammatory properties by inducing transcription of multiple IFN stimulated genes (ISG), a response that is partly mediated by Interferon regulatory factors (IRFs). This chapter provides a brief introduction of the interferon system as well as an in-depth assessment of the interferon signature and the various assay procedures for synthesizing non-natural interferon analogs for structural analysis, which may be helpful in designing improved products and act as a diagnostic tool for neurodegenerative disorders

Effect of sodium nitroprusside on H⁺ -ATPase activity and ATP concentration in <i>Candida albicans</i>

873-879ATP hydrolysis by plasma membrane H+-ATPase from Candida albicans has been investigated in presence of nitric oxide and various nutrients (sugars and amino acids). Sodium nitroprusside (SNP) was used as nitric oxide donor. It was found that ATP concentration decreased in SNP treated cells which was more in presence of sugars like glucose, xylose and 2-deoxy-D-glucose and amino acids as compared to their respective controls. The activity of H+-ATPase from plasma membrane decreased by 70 % in SNP treated cells. Both in vivo and in vitro treatments of SNP showed almost similar effects of decrease in ATPase activity. Effect of SNP was more pronounced in presence of nutrients. Interestingly, it was observed that vanadate did not show any independent effect in presence of nitric oxide. Several workers have reported similar type of results with other P-type A TPases. For the first time, it was observed in the present study that in presence of nitric oxide, H+-ATPase activity decreased like other P-type ATPases. Our study indicated that NO had a significant effect on ATP synthesis and activity of H+- ATPase. In the presence of NO, the ATP concentration was decreased indicating it affected mitochondrial electron transport chain. It may be concluded that NO, not only affects (inhibit) mitochondrial electron transport chain but also interferes with H+- ATPase of plasma membrane by changing its conformation resulting in decreased activity

Increased A(3)AR-dependent Vasoconstriction in Diabetic Mice Is Promoted by Myeloperoxidase

Vascular dysfunction importantly contributes to mortality and morbidity in various cardiac and metabolic diseases. Among endogenous molecules regulating vascular tone is adenosine, with the adenosine A(3) receptor (A(3)AR) exerting cardioprotective properties in ischemia and reperfusion. However, overexpression of A(3)AR is suggested to result in vascular dysfunction and inflammation. The leukocyte enzyme myeloperoxidase (MPO) is an important modulator of vascular function with nitric oxide-consuming and proinflammatory properties. Increased MPO plasma levels are observed in patients with cardiovascular disorders like heart failure, acute coronary syndromes, and arrhythmias. Given that vascular dysfunction and inflammation are also hallmarks of diabetes, the role of MPO in adenosine-dependent vasomotor function was investigated in a murine model of diabetes mellitus. Wild-type (WT) and MPO-deficient (Mpo(-/-)) mice were treated with Streptozotocin (STZ), which induced an increase of MPO plasma levels in WT mice and led to enhanced aortic superoxide generation as assessed by dihydroethidium staining in STZ-treated WT mice as compared with controls. The vasoconstriction of aortic segments in response to the A(3)AR agonist Cl-IB-MECA (2-Chloro-N6-(3-iodobenzyl)-N-methyl-5-carbamoyladenosine) as determined by isometric force measurements was augmented in diabetic WT as compared with diabetic Mpo(-/-) mice. Moreover, A(3)AR protein expression was enhanced in STZ-treated mice but was attenuated by MPO deficiency. The current data reveal an MPO-mediated increase of vascular A(3)AR expression under diabetic conditions, which leads to enhanced vasoconstriction in response to A(3)AR agonists and discloses an additional mechanism of MPO-mediated vascular dysfunction