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111.
Computational tools occupy the prime position in the analysis of large volume of post-genomic data. These tools have advantage over the wet lab experiments in terms of high coverage, cost and time. Breast cancer is the most common cancer in females worldwide. It is a genetically heterogeneous disorder and many genes are involved in the pathway of the disease. Mutations in metastasis suppressor gene are the major cause of the disease. In this study, the effects of mutations in breast cancer metastasis suppressor 1gene upon protein structure and function were examined by means of computational tools and information from databases.This study can be useful to predict the potential effect of every allelic variant, devise new biological experiments and to interpret and predict the patho-physiological impact of new mutations or non-synonymous polymorphisms.  相似文献   
112.
Heavy metal contamination in soil is an important environmental problem and it has negative effect on agriculture. Bacteria play a major role in phytoremediation of heavy metals contaminated soil. In this study, the effect of Bacillus licheniformis NCCP-59, a halophilic bacterium isolated from salt mines near Karak, Pakistan, were determined on a three week old greenhouse grown seedling and germinating seeds of two rice varieties (Basmati-385 (B-385) and KSK-282) in soil contaminated with different concentrations (0, 100, 250, 500, and 1000 ppm) of Nickel. Nickel significantly reduced the germination rate and germination percentage mainly at 500 and 1000 ppm. Significant decrease in ion contents (Na, K, and Ca) was observed while Ni ion concentration in the plant tissues increases as the concentration of Ni applied increases. The photosynthetic pigments (chlorophyll a (chl a), chlorophyll b (chl b), and carotenoids) were also decreased by the application of different concentrations of Ni. Total protein and organic nitrogen were found to be reduced at higher concentrations of Nickel. Inoculation of Bacillus Licheniformis NCCP-59 improved seed germination and biochemical attribute of the plant under Ni stress. It is clear from the results that the Bacillus Licheniformis NCCP-59 strain has the ability to protect the plants from the toxic effects of nickel and can be used for the phytoremediation of Ni contaminated soil.  相似文献   
113.
The degradation kinetics of 5 × 10−5 M cyanocobalamin (B12) and hydroxocobalamin (B12b) in the presence of ascorbic acid (AH2) was studied in the pH range of 1.0–8.0. B12 is degraded to B12b which undergoes oxidation to corrin ring cleavage products. B12b alone is directly oxidized to the ring cleavage products. B12 and B12b in degraded solutions were simultaneously assayed by a two-component spectrometric method at 525 and 550 nm without interference from AH2. Both degrade by first-order kinetics and the values of the rate constants at pH 1.0–8.0 range from 0.08 to 1.05 × 10−5 s−1 and 0.22–7.62 × 10−5 s−1, respectively, in the presence of 0.25 × 10−3 M AH2. The t1/2 values of B12 and B12b range from 13.7 to 137.5 h and 2.5–87.5 h, respectively. The second-order rate constants for the interaction of AH2 with B12 and B12b are 0.05–0.28 × 10−2 and 1.10–30.08 × 10−2 M−1 s−1, respectively, indicating a greater effect of AH2 on B12b compared to that of B12. The kobs–pH profiles for both B12 and B12b show the highest rates of degradation around pH 5. The degradation of B12 and B12b by AH2 is affected by the catalytic effect of phosphate ions on the oxidation of AH2 in the pH range 6.0–8.0.KEY WORDS: ascorbic acid, cyanocobalamin, degradation, hydroxocobalamin, kinetics, two-component spectrometry  相似文献   
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115.
We investigated effect of farm yard manure (FYM) and compost applied to metal contaminated soil at rate of 1% (FYM-1, compost-1), 2% (FYM-2, compost-2), and 3% (FYM-3, compost-3). FYM significantly (P < 0.001) increased dry weights of shoots and roots while compost increased root dry weight compared to control. Amendments significantly increased nickel (Ni) in shoots and roots of maize except compost applied at 1%. FYM-3 and -1 caused maximum Ni in shoots (11.42 mg kg?1) and roots (80.92 mg kg?1), respectively while compost-2 caused maximum Ni (14.08 mg kg?1) and (163.87 mg kg?1) in shoots and roots, respectively. Plants grown in pots amended with FYM-2 and compost-1 contained minimum Cu (30.12 and 30.11 mg kg?1) in shoots, respectively. FYM-2 and compost-2 caused minimum zinc (Zn) (59.08 and 66.0 mg kg?1) in maize shoots, respectively. FYM-2 caused minimum Mn in maize shoots while compost increased Mn in shoots and roots compared to control. FYM and compost increased the ammonium bicarbonate diethylene triamine penta acetic acid (AB-DTPA) extractable Ni and Mn in the soil and decreased Cu and Zn. Lower remediation factors for all metals with compost indicated that compost was effective to stabilize the metals in soil compared to FYM.  相似文献   
116.
Water is essential for the growth period of crops; however, water unavailability badly affects the growth and physiological attributes of crops, which considerably reduced the yield and yield components in crops. Therefore, a pot experiment was conducted to investigate the effect of foliar phosphorus (P) on morphological, gas exchange, biochemical traits, and phosphorus use efficiency (PUE) of maize (Zea mays L.) hybrids grown under normal as well as water deficit situations at the Department of Agronomy, University of Agriculture Faisalabad, Pakistan in 2014. Two different treatments (control and P @ 8 kg ha−1 ) and four hybrids (Hycorn, 31P41, 65625, and 32B33) of maize were tested by using a randomized complete block design (RCBD) with three replications. Results showed that the water stress caused a remarkable decline in total soluble protein (9.7%), photosynthetic rate (9.4%) and transpiration rate (13.4%), stomatal conductance (10.2%), and internal CO2 rate (20.4%) comparative to well-watered control. An increase of 37.1%, 36.8%, and 24.5% were recorded for proline, total soluble sugar, and total free amino acid, respectively. However, foliar P application minimized the negative impact of drought by improving plant growth, physio-biochemical attributes, and PUE in maize plants under water stress conditions. Among the hybrids tested, the hybrid 6525 performed better both under stress and non-stress conditions. These outcomes confirmed that the exogenous application of P improved drought stress tolerance by modulating growth, physio-biochemical attributes, and PUE of maize hybrids.  相似文献   
117.
The mitochondrial permeability transition (MPT) plays an important role in hepatocyte death caused by ischemia-reperfusion (IR). This study investigated whether activation of the cellular oxygen-sensing signal cascade by prolyl hydroxylase inhibitors (PHI) protects against the MPT after hepatic IR. Ethyl 3,4-dihyroxybenzoate (EDHB, 100 mg/kg ip), a PHI, increased mouse hepatic hypoxia-inducible factor-1alpha and heme oxygenase-1 (HO-1). EDHB-treated and untreated mice were subjected to 1 h of warm ischemia to approximately 70% of the liver followed by reperfusion. Mitochondrial polarization, cell death, and the MPT were assessed by intravital confocal/multiphoton microscopy of rhodamine 123, propidium iodide, and calcein. EDHB largely blunted alanine aminotransferase (ALT) release and necrosis after reperfusion. In vehicle-treated mice at 2 h after reperfusion, viable cells with depolarized mitochondria were 72%, and dead cells were 2%, indicating that depolarization preceded necrosis. Mitochondrial voids excluding calcein disappeared, indicating MPT onset in vivo. NIM811, a specific inhibitor of the MPT, blocked mitochondrial depolarization after IR, further confirming that mitochondrial depolarization was due to MPT onset. EDHB decreased mitochondrial depolarization to 16% and prevented the MPT. Tin protoporphyrin (10 micromol/kg sc), an HO-1 inhibitor, partially abrogated protection by EDHB against ALT release, necrosis, and mitochondrial depolarization. In conclusion, IR causes the MPT and mitochondrial dysfunction, leading to hepatocellular death. PHI prevents MPT onset and liver damage through an effect mediated partially by HO-1.  相似文献   
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119.
The status of vitamin D in individuals infected with human immunodeficiency virus (HIV), particularly in naïve as well as treated patients, has never been reported in the Pakistani population. A cross-sectional study was performed to measure vitamin D in individuals infected with HIV living in various districts of the Punjab, Pakistan. 1000 persons attending various treatment centers of the Punjab were screened for HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), and Syphilis. Total 398 patients met inclusion criteria and vitamin D level was measured in respective cases by using enzyme-linked immunosorbent assay (ELISA) technique. 232 samples from the healthy population were also included in present research. Demographic history and clinical parameters regarding HIV disease were evaluated. Comparison of variables was done to find out the link between vitamin D levels and characteristics of HIV infected persons and comparison to that of healthy individuals was performed. Among 398 HIV patients vitamin D deficiency and insufficiency was found among 15 % and 39 % while majority of the control participants had sufficient levels of vitamin D (78 %). Most of the HIV infected individuals were males (68.6 %) and had age between 24 and 47 years (67.8 %). A significant relationship was found for vitamin D level, lifestyle and CD4 count among HIV + ve non acquired immunodeficiency syndrome (AIDS) subjects (95 % CI; p < 0.001, p = 0.09). For HIV + ve AIDS patients vitamin D had a significant relationship with lifestyle along with HIV viral load and CD4 count. Hypovitaminosis D prevails among the HIV infected population of Punjab, Pakistan.  相似文献   
120.
The life cycles of apicomplexan parasites progress in accordance with fluxes in cytosolic Ca2+. Such fluxes are necessary for events like motility and egress from host cells. We used genetically encoded Ca2+ indicators (GCaMPs) to develop a cell-based phenotypic screen for compounds that modulate Ca2+ signaling in the model apicomplexan Toxoplasma gondii. In doing so, we took advantage of the phosphodiesterase inhibitor zaprinast, which we show acts in part through cGMP-dependent protein kinase (protein kinase G; PKG) to raise levels of cytosolic Ca2+. We define the pool of Ca2+ regulated by PKG to be a neutral store distinct from the endoplasmic reticulum. Screening a library of 823 ATP mimetics, we identify both inhibitors and enhancers of Ca2+ signaling. Two such compounds constitute novel PKG inhibitors and prevent zaprinast from increasing cytosolic Ca2+. The enhancers identified are capable of releasing intracellular Ca2+ stores independently of zaprinast or PKG. One of these enhancers blocks parasite egress and invasion and shows strong antiparasitic activity against T. gondii. The same compound inhibits invasion of the most lethal malaria parasite, Plasmodium falciparum. Inhibition of Ca2+-related phenotypes in these two apicomplexan parasites suggests that depletion of intracellular Ca2+ stores by the enhancer may be an effective antiparasitic strategy. These results establish a powerful new strategy for identifying compounds that modulate the essential parasite signaling pathways regulated by Ca2+, underscoring the importance of these pathways and the therapeutic potential of their inhibition.  相似文献   
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