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51.
52.
The cancer profile in the Indian state of Uttarakhand reveals that the breast cancer is the most prevalent type of cancers in females followed by cervical and ovarian type. Literature survey shows that the E6 protein of Human Papilloma Virus-16 (HPV-16) is responsible for causing several forms of cancer in human. Therefore, it is of interest to screen HPV-16 E6 target protein with known natural compounds using computer aided molecular modeling and docking tools. The complete structure of E6 is unknown. Hence, the E6 structure model was constructed using different online servers followed by molecular docking of Colchine, Curcumin, Daphnoretin, Ellipticine and Epigallocatechin-3-gallate; five known natural compounds with best E6 protein model predicted by Phyre2 server. The screening exercise shows that Daphnoretin (with binding free energy of -8.3 kcal/mol), a natural compound derived from Wikstroemia indica has the top binding properties. Thus, it is of interest to consider the compound for further validation.  相似文献   
53.
Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteinases that are capable of cleaving all extra cellular matrix (ECM) substrates. Degradation of matrix is a key event in progression, invasion and metastasis of potentially malignant and malignant lesions of the head and neck. It might have an important polymorphic association at the promoter regions of several MMPs such as MMP-1 (-1607 1G/2G), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T) and TIMP-2 (-418 G/C or C/C). Tissue inhibitors of metalloproteinases (TIMPs) are naturally occurring inhibitors of MMPs, which inhibit the activity of MMPs and control the breakdown of ECM. Currently, many MMP inhibitors (MMPIs) are under development for treating different malignancies. Useful markers associated with molecular aggressiveness might have a role in prognostication of malignancies and to better recognize patient groups that need more antagonistic treatment options. Furthermore, the introduction of novel prognostic markers may also promote exclusively new treatment possibilities, and there is an obvious need to identify markers that could be used as selection criteria for novel therapies. The objective of this review is to discuss the molecular functions and polymorphic association of MMPs and TIMPs and the possible therapeutic aspects of these proteinases in potentially malignant and malignant head and neck lesions. So far, no promising drug target therapy has been developed for MMPs in the lesions of this region. In conclusion, further research is required for the development of their potential diagnostic and therapeutic possibilities.  相似文献   
54.
Citrus tristeza virus (CTV) is a major pathogen of Citrus. A single dominant gene Ctv present in the trifoliate relative of Citrus, Poncirus trifoliata confers broad spectrum resistance against CTV. Refinement of genetic maps has delimited this gene to a 121 kb region, comprising of ten candidate Ctv resistance genes. The ten candidate genes were individually cloned in Agrobacterium based binary vector and transformed into three CTV susceptible grapefruit varieties. Two of the candidate R-genes, R-2 and R-3 are exclusively expressed in transgenic plants and in Poncirus trifoliata, while five other genes are also expressed in non-transformed Citrus controls. Northern blotting with a CTV derived probe for assessment of infection in virus inoculated plants over a span of three growth periods, each comprising of six to eight weeks, indicates either an absence of initiation of infection or it’s slow spread in R-2 plant lines or an initial appearance of infection and it’s subsequent obliteration in some R-1 and R-4 plant lines. Limited genome walk up- and downstream form R-1 gene, based on it’s 100% sequence identity between Poncirus and Citrus, indicates promoter identity of 92% between the two varieties. Further upstream and downstream sequencing indicates the presence of an O-methyl transferase and a Copia like gene respectively in Citrus instead of the amino acid transporter like gene upstream and a sugar transporter like gene downstream in Poncirus. The possibility of recombinations in the resistance locus of Citrus and the need for consistent monitoring for virus infection and gene expression in the transgenic Citrus trees is discussed. Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users.  相似文献   
55.
The biochemical and molecular basis of the defense in a mild tolerant (ICPL-332) and susceptible (ICPL-87) cultivars of pigeon pea (Cajanus cajan) due to Helicoverpa. armigera infestation was studied. We found that feeding by the larvae generated H2O2 in a localized manner and activity was observed upto 12?h (hrs) of with a sharp decline within 24?h. Similarly, PPO activity was also detected till 12?h of treatment, which decreased after 24?h of feeding by larvae. The activity of trypsin inhibitor was detected in all the treatments when assayed at 12 and 24?h after larval feeding. The expression of defense genes like the Pre-hevein-like protein PR-4 precursor (PR-4), protease inhibitor/seed storage/LTP family protein (Ltp) were significantly up-regulated in ICPL-332 upon infestation after 12?h as compared to ICPL-87, whereas the endo 1, 4 -β-glucanase (Kor-1) gene was expressed in both the cultivars after 24?h of infestation. Both the cultivars varied with respect to the induction of defense-related genes during larval feeding, both the PR-4 and Ltp genes appeared to be important for defense against H. armigera in pigeon pea. Thus, the present study revealed an insight of herbivore-induced biochemical and molecular changes in pigeon pea.  相似文献   
56.
The objective of this study was to functionally assess gamma/delta (γδ) T cells following pathogenic human immunodeficiency virus (HIV) infection of humans and nonpathogenic simian immunodeficiency virus (SIV) infection of sooty mangabeys. γδ T cells were obtained from peripheral blood samples from patients and sooty mangabeys that exhibited either a CD4-healthy (>200 CD4+ T cells/μl blood) or CD4-low (<200 CD4 cells/μl blood) phenotype. Cytokine flow cytometry was utilized to assess production of Th1 cytokines tumor necrosis factor alpha and gamma interferon following ex vivo stimulation with either phorbol myristate acetate/ionomycin or the Vδ2 γδ T-cell receptor agonist isopentenyl pyrophosphate. Sooty mangabeys were observed to have higher percentages of γδ T cells in their peripheral blood than humans did. Following stimulation, γδ T cells from SIV-positive (SIV+) mangabeys maintained or increased their ability to express the Th1 cytokines regardless of CD4+ T-cell levels. In contrast, HIV-positive (HIV+) patients exhibited a decreased percentage of γδ T cells expressing Th1 cytokines following stimulation. This dysfunction is primarily within the Vδ2+ γδ T-cell subset which incurred both a decreased overall level in the blood and a reduced Th1 cytokine production. Patients treated with highly active antiretroviral therapy exhibited a partial restoration in their γδ T-cell Th1 cytokine response that was intermediate between the responses of the uninfected and HIV+ patients. The SIV+ sooty mangabey natural hosts, which do not proceed to clinical AIDS, provide evidence that γδ T-cell dysfunction occurs in HIV+ patients and may contribute to HIV disease progression.  相似文献   
57.
58.

Background

Little is known about the treatment of multidrug-resistant tuberculosis (MDR-TB) in HIV-co-infected adolescents. This study aimed to present the intermediate outcomes of HIV-infected adolescents aged 10–19 years receiving second-line anti-TB treatment in a Médecins Sans Frontières (MSF) project in Mumbai, India.

Methods

A retrospective review of medical records of 11 adolescents enrolled between July 2007 and January 2013 was undertaken. Patients were initiated on either empirical or individualized second-line ambulatory anti-TB treatment under direct observation.

Results

The median age was 16 (IQR 14–18) years and 54% were female. Five (46%) adolescents had pulmonary TB (PTB), two (18%) extrapulmonary disease (EPTB) and four (36%) had both. Median CD4 count at the time of MDR-TB diagnosis was 162.7 cells/µl (IQR: 84.8–250.5). By January 2013, eight patients had final and 3 had interim outcomes. Favourable results were seen in four (36.5%) patients: one was cured and three were still on treatment with negative culture results. Seven patients (64%) had poor outcomes: four (36.5%) died and three (27%) defaulted. Three of the patients who died never started on antiretroviral and/or TB treatment and one died 16 days after treatment initiation. Two of the defaulted died soon after default. All patients (100%) on-treatment experienced adverse events (AEs): two required permanent discontinuation of the culprit drug and two were hospitalized due to AEs. No patient required permanent discontinuation of the entire second-line TB or antiretroviral regimens.

Conclusions

Early mortality and mortality after default were the most common reasons for poor outcomes in this study. Early mortality suggests the need for rapid diagnosis and prompt treatment initiation, and adolescents might benefit from active contact-tracing and immediate referral. Default occurred at different times, suggesting the need for continuous, intensified and individualized psychosocial support for co-infected adolescents. Operational research among co-infected adolescents will be especially important in designing effective interventions for this vulnerable group.  相似文献   
59.

Background

NRTI-sparing regimens may avoid long-term mitochondrial, bone and renal toxicities and maintain viral suppression.

Methods

In the RADAR study, 85 antiretroviral-naïve HIV-infected patients were randomized to receive either raltegravir (RAL) (n = 42) or tenofovir/emtricitabine (TDF/FTC) (n = 43), each with ritonavir-boosted darunavir (DRV/r). Virologic efficacy was assessed at weeks 24 and 48. Bone mineral density (BMD) was assessed by dual energy X-ray absorptiometry (DXA) scan at baseline and week 48, and bone turnover markers (BTM) assessed at weeks 0, 16 and 48.

Results

Using an intention-to-treat analysis, 62.5% of RAL subjects and 83.7% of TDF/FTC subjects were responders (VL<48 copies/mL) at week 48 (p = 0.045; chi-square test). The proportions of patients achieving VL<200 copies/mL were similar: 72.5% and 86.0% (p = 0.175). Premature treatment discontinuation was the main cause for failure. No treatment-emergent resistance was observed. Changes from baseline in RAL vs. TDF/FTC for CD4+ (+199 vs. +216 cells/µL, p = 0.63), total cholesterol/HDL (−0.25 vs. −0.71 mg/dL (p = 0.270), and eGFR (−4.4 vs. −7.9 ml/min, p = 0.44) were comparable between groups. Changes in subtotal BMD to week 48 were: +9.2 with RAL vs. −7 g/cm2 with TDF/FTC (p = 0.002). Mean CTX changes were +0.04 vs. +0.24 ng/mL (p = 0.001), and mean P1NP changes were +3.59 vs. +30.09 ng/mL (p = 0.023). BTM changes at week 16 predicted change in BMD by week 48 (R = −0.394, p = 0.003 for CTX; and R = −0.477, p<0.001 for P1NP).

Conclusion

The NRTI-sparing regimen RAL+DRV/r did not achieve similar week 48 virologic efficacy compared with TDF/FTC+DRV/r, but was better with regard to markers of bone health.

Trial Registration

ClinicalTrials.gov NCT 00677300  相似文献   
60.
Administration of simvastatin (80 mg/kg, po. evening dose) and gemfibrozil (600 mg/kg, po twice) for 30 days produced significant decrease in the level of reduced glutathione, superoxide dismutase, catalase and increase in the level of lipid peroxidation and various serum parameters (creatine phosphokinase, lactate dehydrogenase, serum glutamate oxaloacetate transaminase, creatinine, urea and blood urea nitrogen). This suggested involvement of oxidative stress in rhabdomyolysis. Increase in the level of reduced glutathione, superoxide dismutase, catalase and decrease in the level of lipid peroxidation and serum parameters after administration of antioxidant CoQ10 (10 mg/kg.ip) proved the protective effect of CoQ10 in rhabdomyolysis.  相似文献   
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