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161.
Putative stem cells have been isolated from various tissue fluids such as synovial fluid, amniotic fluid, menstrual blood, etc. Recently the presence of nestin positive putative mammary stem cells has been reported in human breast milk. However, it is not clear whether they demonstrate multipotent nature. Since human breast milk is a non-invasive source of mammary stem cells, we were interested in examining the nature of these stem cells. In this pursuit, we could succeed in isolating and expanding a mesenchymal stem cell-like population from human breast milk. These cultured cells were examined by immunofluorescent labeling and found positive for mesenchymal stem cell surface markers CD44, CD29, SCA-1 and negative for CD33, CD34, CD45, CD73 confirming their identity as mesenchymal stem cells. Cytoskeletal protein marker analysis revealed that these cells expressed mesenchymal stem cells markers, namely, nestin, vimentin, smooth muscle actin and also manifests presence of E-Cadherin, an epithelial to mesenchymal transition marker in their early passages. Further we tested the multipotent differentiation potential of these cells and found that they can differentiate into adipogenic, chondrogenic and oesteogenic lineage under the influence of specific differentiation cocktails. This means that these mesenchymal stem cells isolated from human breast milk could potentially be “reprogrammed” to form many types of human tissues. The presence of multipotent stem cells in human milk suggests that breast milk could be an alternative source of stem cells for autologous stem cell therapy although the significance of these cells needs to be determined. 相似文献
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A co-culture of bacteria responsible for the conversion of butyrate to methane and CO2 was isolated from a cattle-waste treatment plant. The non-methanogenic partner of the co-culture was Syntrophomonas wolfei and the methanogenic partner was Methanobacterium formicicum. Although butyrate degradation occurred at pH<6.0 and below 45°C, methanogenesis was observed at pH>6.5 and above 40°C. 相似文献
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Summary A field experiment was conducted to study the effect of Rhizobium inoculation, nitrogen and simazine application, individually
and in combination, on yield and quality of Bengal gram. Application of nitrogen and simazine, and seed inoculation with Rhizobium
increased the grain yield significantly. The combined treatment of Rhizobium, simazine and nitrogen increased the grain yield
to the extent of 70 per cent over control. Application of simazine increased the methionine content. re]19760609 相似文献
167.
Abstract Sea sediments in tropical regions have been less studied for methanogenesis and methanogens present therein. Three species of methanogens viz. Methanobacterium bryantii, Methanococcus voltae and Methanosarcina barkeri were isolated from Arabian sea sediments collected near the west coast of India. Maximum methane was formed by M. voltae at 3.0% (w/v) NaCl and other two methanogens at 0.06% (w/v) NaCl. M. bryantii and M. barkeri tolerated 2.5 and 3.0% (w/v) NaCl respectively due to which these methanogens must have survived in salt conditions of the sea sediments. 相似文献
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M. S. Kadam A. B. Chaudhari S. B. Chincholkar 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2012,6(3):249-254
Optical fluorescence-quenching-based biosensing cell is described and optimization of covalent binding of highly selective natural iron-chelating peptide secreted by bacteria is suggested. Pyoverdin biosynthesized by Pseudomonas monteilii and having 70% iron chelating activity was immobilized on amino alkylated controlled pore glass (CPG) and cross-linked with glutaraldehyde (2.5%, 28°C, 30 min). The pyoverdin-CPG immobilization was confirmed using fluorescence microscopic images (excitation range, 465–495 nm) for bright green fluorescence and by FTIR spectrum stretching at 3406.4 cm−1 for amino group. The pyoverdin loading capacity of activated CPG matrix was 25 mg g−1 of CPG and its rinsing analysis (leaking profile of the immobilized peptide vs. washing) detected negligible (2–3 μg) pyoverdin in the second wash. 相似文献
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