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Alīgarh, India

Ahmad A.,Central Drug Research Institute | Rasheed N.,Central Drug Research Institute | Banu N.,Am University | Palit G.,Central Drug Research Institute
Stress | Year: 2010

Stress plays a key role in the induction of various clinical disorders by altering monoaminergic response and antioxidant defenses. In the present study, alterations in the concentrations of dopamine (DA), serotonin (5-HT) and their metabolites, and simultaneous changes in the antioxidant defense system and lipid peroxidation in different brain regions (frontal cortex, striatum, and hippocampus) were investigated immediately and 24 h after exposure to chronic unpredictable stress (CUS). CUS involved subjecting SpragueDawley rats to two different types of stressors varying from mild to severe intensity every day in an unpredictable manner, over a period of 7 days. CUS significantly decreased DA and 5-HT concentrations, with increased DA turnover ratios in the selected brain regions. In the frontal cortex and striatum, DA metabolite concentrations were increased; however, in the hippocampus they remained unaltered. Further, a decrease of 5-hydroxyindoleacetic acid content was observed in the frontal cortex and striatum, with no significant alteration in the hippocampus. CUS also reduced the activities of superoxide dismutase and catalase, with increased lipid peroxidation and decreased glutathione levels in the selected brain regions. Glutathione peroxidase activity was increased in the frontal cortex and hippocampus only. The pattern of CUS-induced monoamine and oxidative changes immediately after the last stressor and 24 h later were similar when compared with the control group, indicating that the observed changes were due to the chronic exposure to the various stressors and were not merely acute effects of the last stressor. The altered redox state in the striatum and frontal cortex might be related to the perturbed DA and/or 5HT levels, while the hippocampus seems to be less influenced by CUS in terms of monoamine metabolite changes. These results suggest that the perturbed monoamine levels could interact with the oxidative load during CUS. Hence, the current study has implications for pharmacological interventions targeting both central monoamines and cellular antioxidants as a potential stress management strategy for protecting against central stress-induced disorders. © 2010 Informa Healthcare USA, Inc.

Naqvi A.R.,Plant Molecular Biology Group | Naqvi A.R.,University of North Carolina at Chapel Hill | Sarwat M.,Plant Molecular Biology Group | Sarwat M.,Amity University | And 3 more authors.
Journal of Cellular Physiology | Year: 2012

microRNAs (miRNAs), a recently discovered class of small RNAs, are endogenously transcribed non-coding RNAs that are known to control diverse developmental processes and defense responses. They regulate these pathways by fine-tuning the levels of transcripts to which they bind and cause their cleavage or translation repression. Several studies on the processing of miRNA precursors have shed light on the essential structural features for precise release of miRNA duplexes. The identification of a protein that degrade single stranded small RNA has provided us with some understanding of how miRNA flux is maintained in plants. This review focuses on the genome organization, biogenesis, miRNA activity, and the fate of miRNAs. © 2012 Wiley Periodicals, Inc.

Khan M.W.A.,Al Gomail University of 7th of April | Qadrie Z.L.,University of 7th of April | Khan W.A.,Am University | Khan W.A.,King Khalid University
International Archives of Allergy and Immunology | Year: 2010

Background: Glycated proteins present new immunological epitopes on their surface against which autoantibodies are generated that have a possible role in immunopathogenesis in diabetic complications. Methods: In the present study, in vitro glycation- and reactive oxygen species (ROS)-modified human serum albumin (HSA) has been studied by different spectroscopic techniques (UV and fluorescence) and thermal denaturation profiles. The binding characteristics of circulating autoantibodies in diabetic patients and diabetic patients with secondary complications against native HSA (N-HSA) and ROS-modified glycated HSA (RG-HSA) were assessed by direct and competition enzyme-linked immunosorbent assay (ELISA). In another approach, antibodies against RG-HSA (RG-HSA-Abs) induced in experimental animals were used as an immunochemical probe for the detection of gluco-oxidative lesions in blood proteins of patients (n = 8) with diabetic retinopathy. Results: Modified RG-HSA showed marked structural changes. High recognition of RG-HSA was shown by diabetic serum autoantibodies. Diabetic patients with retinopathy, nephropathy and atherosclerosis showed significantly (p < 0.001) stronger binding to RG-HSA over N-HSA. Normal human sera exhibited negligible binding with either antigen. Competitive inhibition ELISA results show significantly high binding of RG-HSA-Abs to albumin, immunoglobulin G and red blood cell membrane isolated from diabetic retinopathic patients. Conclusion: In conclusion, these results suggest that hyperglycemia together with ROS may contribute to the immunopathogenesis of diabetes-associated complications. Copyright © 2010 S. Karger AG, Basel.

Tabish S.,Am University | Ashraf I.,Am University
International Journal of Ambient Energy | Year: 2015

With rapidly growing energy demands and increased consciousness about the environment, PV installations are being increasingly used in various applications such as communications and lighting. However, one of the major challenges in using a PV source is that they are often subjected to partial shading and rapid fluctuations of shading. In many cases, the PV arrays get partially shaded due to various reasons, resulting in lower energy production yields. This further leads to nonlinearities in characteristics, causing it to get more complicated if the entire array does not receive uniform insolation. In this study, a Simulink-based mathematical model of a PV system has been developed to simulate the performance of a PV system for the various conditions of partial shading. The simulated results have been compared with experimentally obtained results of the various configurations of shading that were used for the partial shading conditions on a commercially available PV module. © 2015 Taylor & Francis

Yadav A.,Am University | Sharma V.R.,Am University | Singh P.P.,Helmholtz Center for Heavy Ion Research | Singh P.P.,TU Darmstadt | And 6 more authors.
Physical Review C - Nuclear Physics | Year: 2012

The probability of incomplete fusion in 13C+159Tb interactions has been measured in the energy range ≈4-7 MeV/nucleon. The variation of the incomplete fusion fraction has been studied in terms of projectile energy and type. Present results are compared with the existing 12C+159Tb data, where a strong projectile structure effect on the incomplete fusion fraction has been observed. It has been found that the probability of incomplete fusion is higher in the case of 12C than for a one-neutron rich 13C projectile. For better insight into the projectile structure effect, a systematic study is presented on the incomplete fusion measured in 12 ,13C,16O+159Tb and 12 ,13C,16O+181Ta systems by Singh and by Babu. The present analysis indicates a strong dependence of incomplete fusion probability on the α-Q value of the projectile at these low energies. © 2012 American Physical Society.

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