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1.
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   
2.
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   
3.
The plankton flora on the northeastern coast of the Gulf of Persia consists of many diatom species, the coccolithophores Gephyrocapsa oceanica and Coccolithus huxleyi, and the blue-green alga, Trichodesmium thiebautii. These are prevalent throughout the year and always at low concentrations, with an average maximum in January of 14463 cells/liter and minimum in June of 802/liter. Such comparative constancy suggests that the flora has the attribute of stability. The individual species fluctuate in a patternless, uncorrelated manner, so that the flora is characterized by the attribute of unpredictability. The turbidity of the shallow water reduces the light so that light is usually neither limiting nor inhibitory. There is a small amount of nitrate always available and ample phosphate and silicate. Pure culture studies of several species show growth from about 12° to 34°. The water was 34° in August of 1977. The flora's responsiveness to these light, nutrient, and temperature quantities makes possible its recovery to normal after advective disturbance in June 1977.Contribution number 4574 from the Woods Hole Oceanographic Institution.Contribution number 4574 from the Woods Hole Oceanographic Institution.  相似文献   
4.
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   
5.
This article presents the COVID-19 situation and control measures taken by the Government of Pakistan. Two waves of pandemic are faced globally and similar in the study area. We have investigated the risk management decision in two phases. Primarily, strict lockdown was observed from March 2020 to July 2020 and smart lockdown was enforced from August 2020 to December 2020. It has been studied that during strict lockdown, COVID cases reduced gradually but reopening of institutes and smart lockdown strategy resulted gradual increase in confirmed cases and death rates. During first wave of COVID-19 in Pakistan, a total confirmed number of patients of COVID-19 were 263,496 till 18th of July 2020 with total deaths of 5,568 people and 204,276 recoveries, while total number of COVID-19 patients reached 555,511 till 9th of February 2021 with total deaths of 12,026 people. Province of Sindh was affected badly with total number of 251,434 COVID-19 cases followed by Punjab Province with total number of 161,347 COVID-19 till 9th of February 2020.  相似文献   
6.
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   
7.
8.
Numerous reagents were employed for differentiating induced pluripotent stem cells (iPSCs) into male germ cells; however, the induction procedure was ineffective. The aim of this study was to improve the in vitro differentiation of mice iPSCs (miPSCs) into male germ cells with retinoic acid (RA) and progesterone (P). miPSCs were differentiated to embryoid bodies (EBs) in suspension with RA with or without progesterone for 0, 4, and 7 days. Then, the expression of certain genes at different stages of male germ cell development including Ddx4 (pre meiosis), Stra8 (meiosis), AKAP3 (post meiosis), and Mvh protein was examined in RNA and/or protein levels by real-time polymerase chain reaction or flow cytometry, respectively. The Stra8 gene expression increased in the RA groups on all days. But, expression of this gene declined in RA + P groups. In addition, an increased expression of Ddx4 gene was observed on day 0 in the P group. Also, a significant upregulation was observed in the expression of AKAP3 gene in the RA + P group on days 0 and 4. However, gene expression decreased in P and RA groups on day 7. The expression of Mvh protein significantly increased in the RA group on day 7. The Mvh expression was also enhanced in the P group on day 4, but it decreased on day 7, while this protein upregulated on day 0 and 7 in the RA + P group. The miPSCs have the capacity for in vitro differentiation into male germ cells by RA and/or progesterone. However, the effects of these inducers depend on the type of combination and an effective time.  相似文献   
9.

Candida albicans (C. albicans) cell wall beta-glucan has been considered as a potential agent in the treatment of cancers due to its anti-tumor properties. Therefore, in the present study, we investigated the anti-cancer effects of Candida cell wall beta-glucan on Lewis lung carcinoma cell line (LL/2) cells. Beta-glucan of C. albicans cell wall was extracted. LL/2 cell line was cultured, then sphere cells and parental cells were exposed to the different concentrations of beta-glucan extracted from C. albicans (10–6000 μg/ml), for 24, 48 and 72 h. Cytotoxicity of beta-glucan was assayed by MTT test, then RNA extracted from cells population (treated and untreated cells), cDNA synthetized and expression level of Sox2, Oct4, C-myc, Nanog genes were also investigated using Real-time methods. At optimal concentrations of 800 and 1000 μg/ml, the extracted beta-glucan showed a significant cytotoxic effect on both parental and sphere cell populations (p?<?0.05). Real-time PCR analysis revealed a decreased expression of Oct4 and Sox2 genes in treatment of cells with beta-glucan compared with control group. Since the extracted beta-glucan showed an inhibitory effect on the expression of Oct4 and Sox2 genes involved in LL/2 metastasis, therefore, beta-glucan can be considered as an anti-tumor agent because of its anti-metastatic properties, however, more in vitro and in vivo studies are needed to provide further evidence on this topic in the future.

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10.
Insect midgut proteases are excellent targets for insecticidal agents such as protease inhibitors. These inhibitors are used for producing transgenic plants, resistant to pests. For achieving this goal, it is necessary to find the nature of specific proteases and their properties for adopting possible pest management procedure. Therefore, characterisation of the enzymes in the gut of the rose sawfly, Arge rosae (Hymenoptera: Argidae), responsible for proteolysis, was performed using a range of synthetic substrates and specific inhibitors. The optimum conditions for general proteases and trypsin were achieved at pH 10. The highest activity for general proteases was obtained at a temperature of 45°C. The use of specific inhibitors and SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) provided evidence to suggest that most of the proteases belonged to the serine group because of high inhibitory effect of phenyl methane sulfonyl fluoride on total proteolytic activity. Also, inhibition assays and zymogram analysis showed that metalloproteases are present in A. rosae digestive system. These results indicated that A. rosae larvae mainly used serine proteases for protein digestion, with chymotrypsin as the dominant form. The kinetic parameters of trypsin-like proteases using N-benzoyl-dl-arg-p-nitroanilide as substrate indicated that the K m and V max values of trypsin in the gut of the fifth instar larvae were 730 ± 17.3 μM and 456 ± 13.85 nmol min?1 mg?1 protein, respectively.  相似文献   
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