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Prolyl hydroxylase domain 2 containing protein (PHD2) is a key protein in regulation of angiogenesis and metastasis. In normoxic condition, PHD2 triggers the degradation of hypoxia-inducible factor 1 (HIF-1α) that induces the expression of hypoxia response genes. Therefore the correct function of PHD2 would inhibit angiogenesis and consequent metastasis of tumor cells in normoxic condition. PHD2 mutations were reported in some common cancers. However, high levels of HIF-1α protein were observed even in normoxic metastatic tumors with normal expression of wild type PHD2. PHD2 malfunctions due to protein misfolding may be the underlying reason of metastasis and invasion in such cases. In this study, we scrutinize the unfolding pathways of the PHD2 catalytic domain’s possible species and demonstrate the properties of their unfolding states by computational approaches. Our study introduces the possibility of aggregation disaster for the prominent species of PHD2 during its partial unfolding. This may justify PHD2 inability to regulate HIF-1α level in some normoxic tumor types.  相似文献   
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The tomato looper, Chrysodeixis chalcites (Esper), is one of the polyphagous pests of several economically crops worldwide. Two-sex life table parameters of C. chalcites reared on eight bean cultivars including white kidney bean (cultivars Daneshkadeh and Dehghan), red kidney bean (cultivars Goli and Naz), common bean (cultivars Khomein, Talash and Sadra) and cowpea (cultivar Mashhad) were studied under laboratory conditions (25 ± 1 °C, 65 ± 5 % RH, a 16:8-h light–dark photoperiod). The shortest larval period of C. chalcites was 14.15 days on common bean Sadra. The longest and shortest development time of total preadult was on white kidney bean Daneshkadeh and common bean Sadra (25.77 and 23.42 days, respectively). The highest total fecundity was on common bean Sadra (674.4 eggs), and the lowest was observed on white kidney bean Daneshkadeh (136.7 eggs). The intrinsic rate of increase (r m ) ranged from 0.0976 to 0.1599 female/female/day, which was lowest on white kidney bean Daneshkadeh and highest on common bean Sadra. The net reproductive rate (R 0) was highest on common bean Sadra (265.82 offspring) and lowest on white kidney bean Daneshkadeh (46.88 offspring). The results revealed that the cultivar Daneshkadeh was unsuitable host to C. chalcites in comparison to the other cultivars tested.  相似文献   
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The electro-oxidation of epinephrine (EP), uric acid (UA), folic acid (FA), and their mixture has been studied by modified carbon nanotube paste electrode of 2,2'-[1,2-ethanediylbis(nitriloethylidyne)]-bis-hydroquinone using cyclic voltammetry, chronoamperometry and differential pulse voltammetry. This modified electrode exhibited potent and persistent electron mediating behavior followed by well-separated oxidation peaks towards EP, UA and FA with activation overpotential. For the ternary mixture containing EP, UA and FA the three compounds can be well separated from each other at the scan rate of 20mVs(-1). The obtained catalytic peak current, was linearly dependent on the EP, UA and FA concentrations in the range of 0.7-1200muM, 25-750muM and 15-800muM and the detection limits for EP, UA and FA were 0.216+/-0.004, 8.8+/-0.2 and 11.0+/-0.3muM, respectively. The diffusion coefficient (D), and the kinetic parameters such as electron transfer coefficient, (alpha) and heterogeneous rate constant, (k') for EP were also determined using electrochemical approaches. The modified electrode showed good sensitivity, selectivity and stability, and was employed for the determination of EP, UA and FA in the real samples.  相似文献   
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Present study investigates relationships between total and bioaccessibility of trace elements (Cd, Co, Cr, Cu, Mn, NI, Pb, V, and Zn) concentrations in sediment and their bioaccumulation in species in Shadegan wetland in southwest of Iran. Bioavailability factor (BAF) and translocation factor (TF) were calculated in plants and trophic transfer factor (TTF) was determined in bird species. For this purpose, sampling of sediments, aquatic plants including Phragmites australis, Typha australis, Scripus maritimus and two bird species encircling Porphyrio porphyrio and globally threatened Marmaronetta angustirostris were carried out during winter 2009. Result of chemical analysis show that bioaccessibility concentrations of Mn (8.31 mg/kg), V (1.33 mg/kg), and Pb (1.03 mg/kg) are higher than other metals. The uptake trend of trace elements in plant decreases as root > stem > leaf. Accumulation levels of trace elements in different tissues of P. porphyrio and M. angustirostris are almost identical and considerable. Accumulation and toxicity of Cd in birds is more than plants. In addition, BAF of V, Pb, and Cr indicates high accumulation by plants and great pollution rate in the area of study. In S. maritimus TF for Mn, Cu, Pb, and V are high whereas in T. australis, Cu and Pb posses the highest TF. Also Cr, Co, Mn, Ni, and Zn have higher TF from stem to leaf than root to stem in P. australis. Finally, TTFs were compared in various bird species.  相似文献   
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Molecular Biology Reports - Monoclonal antibodies (mAbs) are widely employed as invaluable therapeutics for a vast number of human disorders. Several approaches have been introduced for the...  相似文献   
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Next-generation sequencing of cell-free circulating solid tumor DNA addresses two challenges in contemporary cancer care. First this method of massively parallel and deep sequencing enables assessment of a comprehensive panel of genomic targets from a single sample, and second, it obviates the need for repeat invasive tissue biopsies. Digital SequencingTM is a novel method for high-quality sequencing of circulating tumor DNA simultaneously across a comprehensive panel of over 50 cancer-related genes with a simple blood test. Here we report the analytic and clinical validation of the gene panel. Analytic sensitivity down to 0.1% mutant allele fraction is demonstrated via serial dilution studies of known samples. Near-perfect analytic specificity (> 99.9999%) enables complete coverage of many genes without the false positives typically seen with traditional sequencing assays at mutant allele frequencies or fractions below 5%. We compared digital sequencing of plasma-derived cell-free DNA to tissue-based sequencing on 165 consecutive matched samples from five outside centers in patients with stage III-IV solid tumor cancers. Clinical sensitivity of plasma-derived NGS was 85.0%, comparable to 80.7% sensitivity for tissue. The assay success rate on 1,000 consecutive samples in clinical practice was 99.8%. Digital sequencing of plasma-derived DNA is indicated in advanced cancer patients to prevent repeated invasive biopsies when the initial biopsy is inadequate, unobtainable for genomic testing, or uninformative, or when the patient’s cancer has progressed despite treatment. Its clinical utility is derived from reduction in the costs, complications and delays associated with invasive tissue biopsies for genomic testing.  相似文献   
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The immunomodulatory and anti-inflammatory properties of bone marrow-derived mesenchymal stem cells (BM-MSCs) have been considered as an appropriate candidate for treatment of autoimmune diseases. Previous studies have revealed that treatment with BM-MSCs may modulate immune responses and alleviate the symptoms in experimental autoimmune encephalomyelitis (EAE) mice, an animal model of multiple sclerosis. Therefore, the present study was designed to examine immunomodulatory effects of BM-MSCs in the treatment of myelin oligodendrocyte glycoprotein (MOG) 35-55-induced EAE in C57BL/6 mice. MSCs were obtained from the bone marrow of C57BL mice, cultured with DMEM/F12, and characterized with flow cytometry for the presence of cell surface markers for BM-MSCs. Following three passages, BM-MSCs were injected intraperitoneally into EAE mice alone or in combination with rapamycin. Immunological and histopathological effects of BM-MSCs and addition of rapamycin to BM-MSCs were evaluated. The results demonstrated that adding rapamycin to BM-MSCs transplantation in EAE mice significantly reduced inflammation infiltration and demyelination, enhanced the immunomodulatory functions, and inhibited progress of neurological impairments compared to BM-MSC transplantation and control groups. The immunological effects of rapamycin and BM-MSC treatments were associated with the inhibition of the Ag-specific lymphocyte proliferation, CD8+ cytolytic activity, and the Th1-type cytokine (gamma-interferon (IFN-γ)) and the increase of Th-2 cytokine (interleukin-4 (IL-4) and IL-10) production. Addition of rapamycin to BM-MSCs was able to ameliorate neurological deficits and provide neuroprotective effects in EAE. This suggests the potential of rapamycin and BM-MSC combined therapy to play neuroprotective roles in the treatment of neuroinflammatory disorders.  相似文献   
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