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11.
Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium. 相似文献
12.
Asim Mehmood Umal Baneen Ahmad Zaheer Muhammad Wasim Sajid Abrar Hussain Shahzad Saleem Qudsia Yousafi Hamid Rashid Hassan Riaz Awais Ihsan Farrukh Jamil Yasar Sajjad Nageena Zahid Muhammad Shahzad Anjam Muhammad Arshad Zeenat Mirza Sajjad Karim Mahmood Rasool 《Saudi Journal of Biological Sciences》2019,26(7):1485-1491
ObjectivePhosphorous is an essential micronutrient of plants and involved in critical biological functions. In nature, phosphorous is mostly present in immobilized inorganic mineral and in the fixed organic form including phytic acid and phosphoesteric compounds. However, the bioavailability of bound phosphorous could be enhanced by the use of phosphate solubilizing microorganisms such as bacteria and fungi. The phytases are widespread in an environment and have been isolated from different sources comprising bacteria and fungi.MethodologyIn current studies, we show the successful use of gamma rays and EMS (Ethyl Methane Sulphonate) mutagenesis for enhanced activity of phytases in a fungal strain Sporotrichum thermophile.ResultsWe report an improved strain ST2 that could produce a clear halo zone around the colony, up to 24 mm. The maximum enzymatic activity was found of 382 U/mL on pH 5.5. However, the phytase activity was improved to 387 U/ml at 45 °C. We also report that the mutants produced through EMS showed the greater potential for phytase production.ConclusionThe current study highlights the potential of EMS mutagenesis for strain improvement over physical mutagens. 相似文献
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Oral pathogens have created a menace in recent years due to biofilm formation and antimicrobial drug resistance. The current treatment strategy works well with antibiotics. However, constant use of antibiotics creates a selective pressure, which increases adaptability of the pathogens. Therefore, it is of interest to analyze the potential targets of genistein in dental pathogens using computer aided prediction tools. 相似文献
15.
Background
Annotation of sequences that share little similarity to sequences of known function remains a major obstacle in genome annotation. Some of the best methods of detecting remote relationships between protein sequences are based on matching sequence profiles. We analyse the superfamily specific performance of sequence profile-profile matching. Our benchmark consists of a set of 16 protein superfamilies that are highly diverse at the sequence level. We relate the performance to the number of sequences in the profiles, the profile diversity and the extent of structural conservation in the superfamily. 相似文献16.
Background
Existing cut-offs for fasting plasma glucose (FPG) and post-load glucose (2hPG) criteria are not equivalent in the diagnosis of diabetes and glucose intolerance. Adjusting cut-offs of single measurements have not helped so we undertook this project to see if they could be complementary. 相似文献17.
Voltammetric measurements on solutions of human hemoglobin using gold electrodes modified with omega-hydroxyalkanethiols have yielded the first direct measure of the reorganization energy of the protein. The value obtained based on extrapolation of the experimentally measured currents, 0.76 eV, is independent of pH (i.e., over the physiologically relevant rage, pH 6.8-7.4) and is remarkably similar to values obtained for myoglobin. This result is perhaps surprising given the marked dependence of the measured reduction potential of hemoglobin on pH (i.e., the redox Bohr effect). Electron transfer rates from the electrode to hemoglobin were also measured. Using similarly measured heterogeneous electron-transfer rates for cytochrome b(5), it is possible to predict the magnitude of the homogeneous electron-transfer rate from cytochrome b(5) to methemoglobin using a formalism developed by Marcus. These predicted rates are in reasonable agreement with reported rates of this physiological reaction based on stopped-flow kinetics experiments. These results suggest that the intrinsic electroreactivity of these heme proteins is sufficient to account for physiologically observed rates. Residual differences between homogeneous phase kinetics and those predicted by heterogeneous phase reactions are suggested to be due to small reductions in the outer-sphere reorganization energy of both component proteins which arise due to solvent exclusion at the interface between the two proteins in complex. 相似文献
18.
Plant regeneration through indirect somatic embryogenesis was attempted from the immature cotyledon-derived explant of Cassia angustifolia Vahl. — a valuable leguminous shrub. The highest frequency (90.5 %) of somatic embryos was obtained on a Murashige and Skoog (MS) medium augmented with 10.0 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.0 μM benzyladenine (BA) with the production of a maximum of 22.8 embryos per explant, of which 35.3 % germinated on the same medium after 6 weeks of culture. A half strength MS medium without plant growth regulators facilitated better conversion of embryos into complete plantlets compared to a full strength MS medium. Regenerated plantlets were successfully acclimatized in sterile Soilrite and transferred to field conditions with a 70 % survival rate. Histological studies performed at different stages of embryogenesis revealed the mode of differentiation of embryos from the callus. The content of chlorophylls (a + b) and carotenoids, and the net photosynthetic rate (PN) in the regenerated plantlets were tested during different periods of acclimatization. 相似文献
19.
Ahmed S Abdel-Moneim Ahmad E Abdel-Ghany Salama AS Shany 《Journal of biomedical science》2010,17(1):25
Background
The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences. 相似文献20.
Somatic embryogenesis (SE) has been achieved from hypocotyl-derived callus culture in Pterocarpus marsupium. Ninety percent of hypocotyl explants (excised from 12-day-old in vitro germinated axenic seedlings) produced callus on Murashige and Skoog medium supplemented with 5 μM 2,4-dichlorophenoxyacetic acid and 1 μM a 6-benzyladenine (BA). Induction of SE occurred after transfer of callus clumps (200 ± 20 mg fresh mass) to MS medium supplemented with BA at 2.0 μM, where a maximum of 23.0 ± 0.88 globular stage embryos per callus clump were observed after 4 weeks of culture. Subculturing of these embryos on MS medium supplemented with 0.5 μM BA, 0.1 μM α-naphthalene acetic acid and 10 μM abscisic acid significantly enhanced the maturation of somatic embryos to early cotyledonary stage, where 21.4 ± 0.32 embryos per callus clump were recorded after 4 weeks of culture. Of 30-well developed somatic embryos, 16.6 ± 0.33 germinated and subsequently converted into plantlets on half-strength MS medium supplemented with 1.0 μM BA. The morphologically normal plantlets with well-developed roots were first transferred to 1/4-liquid MS medium for 48 h and then to pots containing autoclaved soilrite and acclimatized in a culture room. Thereafter, they were transferred to a greenhouse, where 60% of them survived. 相似文献