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91.
The mechanism of transport of trace elements from the mother to the newborn is still not well known. The aim of present study was to compare the status of trace toxic elements, arsenic (As), cadmium (Cd), and lead (Pb) in biological samples (whole blood, urine and scalp hair) of insulin-dependent diabetic mothers (age ranged 30-40) and their newly born infants (n = 76). An age and socioeconomics matched 68 nondiabetic mothers and their infants, residing in the same locality, who were selected as referents. The elemental concentrations in all three biological samples were determined by an electrothermal atomic absorption spectrometer, prior to microwave-assisted acid digestion. The mean values of As, Cd, and Pb in all biological samples of diabetic mothers and their infants were significantly higher as compared to the referent mother-infant pair samples (p < 0.01). The high levels of As, Cd, and Pb in biological samples of diabetic women may play a role in the pathogenesis of diabetes mellitus and impacts on their neonates.  相似文献   
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Recombinant human β-mannosidase (rhMANB) is an important glycosidase enzyme that degrades mannose-linked glycoproteins and mannan polysaccharides. rhMANB was purified and covalently immobilized onto magnetic nanoparticles. The immobilization of the enzyme was confirmed by Fourier-transform infrared spectroscopy (FTIR) and magnetic nanoparticles linked immunosorbent assay (MagLISA). Antibodies against rhMANB were raised, purified and characterized for MagLISA. The binding of rhMANB onto magnetic nanoparticles was found to be 65%. The V( max ) and K( m ) of immobilized rhMANB was observed 3.0-fold higher and 2.024-fold lower, respectively, as compared to unbound rhMANB. The stability and activity of immobilized enzyme was observed at different pH, temperature, and after storage at 4°C. Metal chelators (oxalic acid, citric acid, and ascorbic acid) did not affect the enzyme activity of immobilized enzyme, whereas ethylenediamine tetraacetic acid reduced the activity. The results obtained from thin-layer chromatography indicate that immobilized rhMANB is more efficient than the unbound form to hydrolyze mannobiose, mannotriose, mannotetraose, mannopentose, galactoglucomannan, and locust bean gum. Magnetic nanoparticles suspended gel-permeation chromatography showed that 29% locust bean gum hydrolyzed efficiently during flow in the column. The immobilization of rhMANB will be a good process for gelling and saccharification of mannan polymers at industrial scale.  相似文献   
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Immune cells within the granulomas of murine schistosomiasis mansoni make the neuropeptide substance P (SP) and express neurokine 1 receptor, which is the specific receptor for substance P (SPr). It was determined if mice with deletion of the SPr (SPr-/-) would develop a normal granulomatous response to schistosome ova during the course of natural infection. Mean liver granuloma size was smaller in SPr-/- mice compared with that of wild-type control animals. Although flow analysis revealed little difference in the cellular composition of the granulomas, both splenocytes and granuloma cells from SPr-/- mice produced much less IFN-gamma and IgG2a and less IgE. The expression of Th2 cytokines (IL-4/IL-5) and IgG1 was comparable to the wild-type control. The mouse with targeted disruption of its SPr had the nonmammalian gene encoding the enzyme beta-galactosidase inserted in exon 1 of the SPr gene. There was beta-galactosidase activity in many mononuclear cells scattered throughout the schistosome granulomas of SPr-/- mice. Also, a granuloma T cell line derived from this transgenic mouse produced beta-galactosidase. These results provide further evidence that in murine schistosomiasis SPr is displayed commonly on granuloma inflammatory cells and is important for granuloma development and expression of IFN-gamma circuitry in this natural infection.  相似文献   
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Molecular Biology Reports - Pakistan ranked highest with reference to average temperatures in cotton growing areas of the world. The heat waves are becoming more intense and unpredictable due to...  相似文献   
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The present study aimed to evaluate the effect of soil-applied Zn and Cu on absorption and accumulation of Cd applied through irrigation water in legume (chickpea and mung bean) and cereal (wheat and maize) crops. The results revealed that Cd in irrigation water at higher levels (2 and 5 mg L?1) significantly (p < 0.05) reduced the plant biomass while the soil application of Zn and Cu, singly or combined, favored the biomass production. Plant tissue Cd concentration increased linearly with the increasing application of Cd via irrigation water. While Cd application caused a redistribution of metals in grains, straw, and roots with the highest concentration of Cd, Zn, and Cu occurred in roots followed by straw and grains. Zinc addition to soil alleviated Cd toxicity by decreasing Cd concentration in plant tissues due to a possible antagonistic effect. The addition of Cu to the soil had no consistent effects on Zn and Cd contents across all crops. Inhibitory effects of Cd on the uptake and accumulation of Zn and Cu have also been observed at higher Cd load. Thus, soil-applied Zn and Cu antagonized Cd helping the plant to cope with its toxicity and suppressed the toxic effects of Cd in plant tissues, thus favoring plant growth.  相似文献   
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Molecular Biology Reports - Vitamin D receptor (VDR) mediates cellular processes like cell cycle arrest and apoptosis which effect cancer susceptibility. VDR single nucleotide polymorphisms (SNPs)...  相似文献   
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