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Human immunodeficiency virus type 1 encoded viral protein Vpr is essential for infection of macrophages by HIV-1. Furthermore, these macrophages are resistant to cell death and are viral reservoir. However, the impact of Vpr on the macrophage proteome is yet to be comprehended. The goal of the present study was to use a stable-isotope labeling by amino acids in cell culture (SILAC) coupled with mass spectrometry-based proteomics approach to characterize the Vpr response in macrophages. Cultured human monocytic cells, U937, were differentiated into macrophages and transduced with adenovirus construct harboring the Vpr gene. More than 600 proteins were quantified in SILAC coupled with LC-MS/MS approach, among which 136 were significantly altered upon Vpr overexpression in macrophages. Quantified proteins were selected and clustered by biological functions, pathway and network analysis using Ingenuity computational pathway analysis. The proteomic data illustrating increase in abundance of enzymes in the glycolytic pathway (pentose phosphate and pyruvate metabolism) was further validated by western blot analysis. In addition, the proteomic data demonstrate down regulation of some key mitochondrial enzymes such as glutamate dehydrogenase 2 (GLUD2), adenylate kinase 2 (AK2) and transketolase (TKT). Based on these observations we postulate that HIV-1 hijacks the macrophage glucose metabolism pathway via the Vpr-hypoxia inducible factor 1 alpha (HIF-1 alpha) axis to induce expression of hexokinase (HK), glucose-6-phosphate dehyrogenase (G6PD) and pyruvate kinase muscle type 2 (PKM2) that facilitates viral replication and biogenesis, and long-term survival of macrophages. Furthermore, dysregulation of mitochondrial glutamate metabolism in macrophages can contribute to neurodegeneration via neuroexcitotoxic mechanisms in the context of NeuroAIDS.  相似文献   
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Onosma echioides Linn (Boraginaceae) is the most frequently used curative herb widely used for kidney obstruction, sciatic pain, and gout. The present study was designed to investigate the therapeutic effects of n-hexane bark extract of O. echioides (OE) L. root in vivo against Streptozotocin-induced diabetic neuropathy in SD rats. For in vivo activity, the experiment was categorized into five different groups (n = 5). Group-I was considered as nondiabetic/normal control (NC) treated with 0.5% carboxymethyl cellulose (CMC), Group II as diabetic control, Group-III, IV, and V served as diabetic treated with OE 50, OE 100, and pregabalin at a dose of 50, 100, and 10 mg/kg body weight, orally, respectively. Body weight, blood glucose, oral glucose tolerance test, behavioral studies (motor coordination test, thermal hyperalgesia, cold allodynia, locomotor activity, oxidative biomarkers (thio barbituric acid reactive substances [TBARS], superoxide dismutase [SOD], glutathione [GSH], and catalase), and histopathology of the sciatic nerve were performed. Treatment with OE showed a dose-dependent increase in neuroprotective activity by improving the myelination and decreasing the axonal swelling of nerve fibers. The verdicts of behavioral activities showed a remarkable effect on animals after the treatment of extract and standard drug pregabalin. In conclusion, our findings supported the traditional application of OE and explored its importance in the management of diabetic neuropathy. Additional clinical experiments may provide novel therapeutic drugs for diabetes and its complications.  相似文献   
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Summary Dantrolene-Na is a muscular relaxant which binds to sarcoplasmic reticulum (SR) with high affinity and decreases the availability of Ca2+ channels. The binding of fluorescent compounds, dantrolene-Na, nifedipine and chlortetracycline to the ciliary membrane ofParamecium aurelia has been studied. Dantrolene at the concentrations of 1.9 · 10–5, 3.8 · 10–5 and 7.9 · 10–5 M manifested a punctuated binding pattern to the cell membrane. Isolated cilia also bound dantrolene at their basal portion, whereas deciliated cell bodies lost their dotted binding pattern. Chlortetracycline showed a similar but weaker fluorescent staining. Nifedipine treated cells revealed no sign of fluorescent binding to the membrane and was only taken up in food vacuoles.Based on these observations we propose that dantrolene binding regular arrays ofParamecium cell membrane could be identical to granular plaques observed by electron microscope. The possible functioning of these structures as Ca2+ reservoirs is also discussed.  相似文献   
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Abstract

The present study was conducted to assess the magnitude and health impacts of As in drinking water. Drinking water samples (n?=?60) were collected from twenty different sites of Shiekhupura District (Pakistan). Health risk assessment through average daily dose (ADD), hazard indices (HI), hazard quotient (HQ), carcinogenic risk (CR), and cancer indices (CI) for dermal and oral exposure were determined. Results revealed that As concentration ranged from 2 to 900?µg?L?1 in water samples, which was significantly greater than the safe limit of As (10?µg?L?1) in water. Health risk assessment of As showed that ADD (1.07E?02–9.85E?04), HQ (1.06E+01–9.85E+00), and CR (1.60E?02–9.85E?04) for oral exposure and ADD (1.03E?05–9.69E?06), HQ (1.19E?02–7.96E?03), and CR (1.11E?05–8.98E?05) for dermal exposure which were exceeded the toxic risk index value. Comparison of the two exposure pathways indicated that the oral exposure is much higher risk than the dermal contact. Both values of HI and CI were greater than WHO limit. It is concluded that residents of study area are at higher risk of As induced diseases and carcinogenicity.  相似文献   
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Plant and Soil - Success in agronomic biofortification of maize and wheat is highly variable. This study aimed to elucidate the differences in uptake and translocation of foliar-applied zinc (Zn)...  相似文献   
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International Journal of Peptide Research and Therapeutics - Natural compounds extracted from marine organisms consisting of biological active materials like collagen provide a major source of...  相似文献   
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The relationship between serum anti-heat shock protein (Hsp)27 antibody and high sensitive C-reactive protein (hs-CRP) levels and indices of cardiac function were investigated in patients undergoing coronary artery bypass grafting (CABG) or heart valve replacement. The changes in anti-Hsp27 antibody titers and hs-CRP levels were compared among patients undergoing off-pump and on-pump CABG or valvular heart replacement. Fifty-three patients underwent off-pump, on-pump CABG, and heart valvular replacement in each group. Serum anti-Hsp27 titers and hs-CRP values were measured 24 h before and after the operation and at discharge. Echocardiography was performed before surgery and before discharge. The results were compared with values from 83 healthy controls. hs-CRP levels increased and anti-Hsp27 antibody decreased following surgery (P < 0.001 and P < 0.05, respectively), although these changes were independent of operative procedure (P = 0.361 and P = 0.120, respectively). Anti-Hsp27 antibody levels were higher at the time of discharge (P = 0.016). Only in coronary patients were anti-Hsp27 antibody levels negatively associated with E/E′ (r = −0.268, P = 0.022), a marker of pulmonary capillary wedge pressure. In conclusions, anti-Hsp27 antibody levels are associated with indices of cardiac function in coronary patients. Cardiopulmonary bypass had no significant effect on the induction of changes in anti-Hsp27 levels. Moreover, anti-Hsp27 antibody levels fell in all groups postoperatively; this may be due to the formation of immune complexes of antigen–antibody, and antibody levels were higher at the time of discharge.

Electronic supplementary material

The online version of this article (doi:10.1007/s12192-012-0358-y) contains supplementary material, which is available to authorized users.  相似文献   
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