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101.
GV Pavlova AA Vergun EY Rybalkina PR Butovskaya AP Ryskov 《Cell cycle (Georgetown, Tex.)》2015,14(2):200-205
Random amplified polymorphic DNA (RAPD) analysis was adapted for genomic identification of cell cultures and evaluation of DNA stability in cells of different origin at different culture passages. DNA stability was observed in cultures after no more than 5 passages. Adipose-derived stromal cells demonstrated increased DNA instability. RAPD fragments from different cell lines after different number of passages were cloned and sequenced. The chromosomal localization of these fragments was identified and single-nucleotide variations in RAPD fragments isolated from cell lines after 8–12 passages were revealed. Some of them had permanent localization, while most variations demonstrated random distribution and can be considered as de novo mutations. 相似文献
102.
A L-lactate-selective microbial biosensor was developed using permeabilized cells of gene-engineered thermotolerant methylotrophic yeast Hansenula polymorpha, over-producing L-lactate:cytochrome c-oxidoreductase (EC 1.1.2.3, flavocytochrome b(2), FC b(2)). The construction of FC b(2)-producers by over-expression of the gene CYB2 H. polymorpha encoding FC b(2) is described. The HpCYB2 gene under the control of the strong H. polymorpha alcohol oxidase promoter in the frame of a plasmid for multicopy integration was transformed to the recipient strain H. polymorpha C-105 (gcr1 catX) impaired in glucose repression and devoid of catalase activity. The permeabilized cells were either immobilized on the graphite working electrode by physical entrapment of the cell suspension by means of a dialysis membrane or by integration of the cells in an electrochemically generated layer using a cathodic electrodeposition polymer. Phenazine methosulphate was used as a free-diffusing redox mediator. It was assumed that the mediator reacts with mitochondrial FC b(2) after entering the cells in the presence of L-lactate. The biosensor based on recombinant yeast cells exhibited a higher K(M)(app) value and hence expanded linear range toward L-lactate as compared to a similar sensor based on the initial cells of H. polymorpha C-105. 相似文献
103.
Abstact Milk and dairy products purchased at Egyptian markets and breast milk from lactating mothers in Cairo and Giza governorates
were analyzed for some mycotoxins. Three of 15 cows’ milk samples were found positive for Afl. M1 with mean value 6.3 ppb. Only one sample of dried milk was positive (5 ppb). Two of 10 hard cheese samples contained detectable
levels of Afl. M1 (3and 6 ppb), whereas one sample containing Afl. B1 and G1 (10 and 4 ppb resp.). For soft cheese one sample of 10 was positive for Afl. M1 (0.5 ppb). Blue veined cheeses were free of Afl. M1 and PR-toxins.
For breast milk two of 10 samples were positive for Afl. M1 (20%) with mean value 2.75 ppb, while 3 of 10 samples were positive for Ochratoxin A (30 %). 相似文献
104.
Background
Monetary incentives are an effective way of increasing response rates to surveys, though they are generally less effective in physicians, and are more effective when the incentive is paid up-front rather than when made conditional on completion. 相似文献105.
Geert Zegels Geert AA Van Raemdonck Wiebren AA Tjalma Xaveer WM Van Ostade 《Proteome science》2010,8(1):63
Cervicovaginal fluid has an important function in the homeostasis and immunity of the lower female genital tract. Analysis
of the cervicovaginal fluid proteome may therefore yield important information about the pathogenesis of numerous gynecological
pathologies. Additionally, cervicovaginal fluid has great potential as a source of biomarkers for these conditions. 相似文献
106.
Lauren Anton David C Merrill Liomar AA Neves Courtney Gruver Cheryl Moorefield K Bridget Brosnihan 《Reproductive biology and endocrinology : RB&E》2010,8(1):135
Background
During preeclampsia, placental angiogenesis is impaired. Factors released from the placenta including vascular endothelial growth factor (VEGF), placental growth factor (PLGF), soluble VEGF receptor 1 (sFlt1), and soluble endoglin (sEng) are regulatory molecules of placental development and function. While the renin angiotensin system has been shown to regulate angiogenic factors in other research fields, these mechanisms have not been extensively studied during pregnancy. 相似文献107.
Oleksandra V. Blazhenko Martin Zimmermann Hyun Ah Kang Grzegorz Bartosz Michel J. Penninckx Vira M. Ubiyvovk Andriy A. Sibirny 《Biometals》2006,19(6):593-599
Intracellular cadmium (Cd2+) ion accumulation and the ability to produce specific Cd2+ ion chelators was studied in the methylotrophic yeast Hansenula polymorpha. Only one type of Cd2+ intracellular chelators, glutathione (GSH), was identified, which suggests that sequestration of this heavy metal in H. polymorpha occurs similarly to that found in Saccharomyces cerevisiae, but different to Schizosaccharomys pombe and Candida glabrata which both synthesize phytochelatins. Cd2+ ion uptake in the H. polymorpha wild-type strains appeared to be an energy dependent process. It was found that Δgsh2 mutants, impaired in the first step of GSH biosynthesis, are characterized by increase in net Cd2+ ion uptake by the cells, whereas Δgsh1/Δmet1 and Δggt1 mutants impaired in sulfate assimilation and GSH catabolism, respectively, lost the ability to accumulate Cd2+ intracellularly. Apparently H. polymorpha, similarly to S. cerevisiae, forms a Cd-GSH complex in the cytoplasm, which in turn regulates Cd2+ uptake. Genes GSH1/MET1 and GGT1 are involved in maturation and metabolism of cellular Cd-GSH complex, respectively. Transport of [3H]N-ethylmaleimide-S-glutathione ([3H]NEM-SG) conjugate into crude membrane vesicules, purified from the wild-type cells of H. polymorpha appeared to be MgATP dependent, uncoupler insensitive and vanadate sensitive. We suggest that MgATP dependent transporter involved in Cd-GSH uptake in H. polymorpha, is similar to S. cerevisiae Ycf1-mediated vacuolar transporter responsible for accumulation of organic GS-conjugates and Cd-GSH complex. 相似文献
108.
Stasyk OV Stasyk OG Mathewson RD Farré JC Nazarko VY Krasovska OS Subramani S Cregg JM Sibirny AA 《Autophagy》2006,2(1):30-38
In methylotrophic yeasts, peroxisomes are required for methanol utilization, but are dispensable for growth on most other carbon sources. Upon adaptation of cells grown on methanol to glucose or ethanol, redundant peroxisomes are selectively and quickly shipped to, and degraded in, vacuoles via a process termed pexophagy. We identified a novel gene named ATG28 (autophagy-related genes) involved in pexophagy in the yeast Pichia pastoris. This yeast exhibits two morphologically distinct pexophagy pathways, micro- and macropexophagy, induced by glucose or ethanol, respectively. Deficiency in ATG28 impairs both pexophagic mechanisms but not general (bulk turnover) autophagy, a degradation pathway in yeast triggered by nitrogen starvation. It is known that the micro-, macropexophagy, and general autophagy machineries are distinct but share some molecular components. The identification of ATG28 suggests that pexophagy may involve species-specific components, since this gene appears to have only weak homologues in other yeasts. 相似文献
109.
Zirconyl hematoxylin stains acidic mucins darkly and specifically using a solution of 100 mg hematoxylin, 5 ml ethanol, 5 ml 0.5% sodium iodate, 400 mg zirconyl chloride octahydrate, and 30 ml 25% aqueous glycerol. The stain is especially advantageous for studying goblet cells and Paget cells. 相似文献
110.
Lyubov R. Fayura Yuriy R. Boretsky Yuriy V. Pynyaha Denys N. Wheatley Andriy A. Sibirny 《Journal of biotechnology》2013
Arginine deiminase is a promising anticancer drug active against melanoma, hepatocarcinoma and other tumors. Recombinant strains of Escherichia coli that express arginine deiminase from pathogenic bacteria Mycoplasma have been developed. However, production costs of heterologous arginine deiminase are high due to use of an expensive inducer and extraction buffer, as well as using diluted culture for enzyme induction. We report on a new advanced protocol for Mycoplasma hominis arginine deiminase expression, extraction and renaturation. The main improvements include manipulation with dense suspensions of E. coli, use of lactose instead of isopropyl β-d-1-thiogalactopyranoside as an inducer and a cheaper but not less efficient buffer for solubilization of arginine deiminase inclusion bodies. In addition, supplementation of the storage culture medium with glucose and substrate (arginine) significantly stabilized the recombinant arginine deiminase producer. Homogenous preparations of recombinant arginine deiminase were obtained using anion-exchange and hydrophobic chromatography. The purified enzyme retained a specific activity of 30–34 U/mg for 12 months when stored at 4 °C in 20 mM sodium phosphate buffer pH 7.2 containing 1 M NaCl. 相似文献