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1.
Kalbolandi Sanaz Moradi Gorji Armita Valizadeh Babaahmadi-Rezaei Hossein Mansouri Esrafil 《Molecular biology reports》2019,46(4):4039-4047
Molecular Biology Reports - This work aims to evaluate the renoprotective effect of luteolin on expression of Nrf2 and miR320 in ischemia–reperfusion (I/R) injury in rats. Thirty rats were... 相似文献
2.
Cryptococcus neoformans was instilled intranasally into mice which were periodically sacrificed to determine the course of infection. Cryptococci persisted within the nasal passages throughout the 90 day study. Extranasal dissemination began 14–28 days after instillation and was still demonstrable 90 days post-exposure. Ten percent mortality was observed in mice receiving 106 cryptococci, while no mortality was observed in mice exposed to 103 or 104 cryptococci. Our research suggests that nasal colonization with C. neoformans can precede pulmonary and systemic cryptococcosis by weeks or months. 相似文献
3.
Philip Himmelfarb Hamed M. El-Bisi R. B. Read Jr. Warren Litsky 《Applied microbiology》1962,10(5):431-435
Because of the low toxicity of its breakdown product, propylene oxide (PO) vapor will play an increasingly important role in the preservation of foods. It is therefore necessary that the diversified variables which influence effectiveness of PO treatment be thoroughly investigated and understood prior to advocating its general use in industry. Accordingly, the present study was undertaken to determine the effect of relative humidity (RH) upon the bactericidal activity of PO sterilant atmospheres. Death rates were established at increasing RH values of < 1, 52, 65, 80, and 98% and under constant conditions of concentration, pressure, and temperature. Test bacterial populations were preconditioned to corresponding moisture levels. Results indicate that gram-positive cocci were relatively insensitive to PO vapor at dry conditions but became progressively less resistant with the increase in RH up to a maximum of 65 to 70%. Lactic acid bacteria and gram-negative rods were much more sensitive at dry conditions, showing much less dependency upon water vapor. Bacillus subtilis spores elicited the highest degree of resistance but the death rate substantially increased with the increase in RH. 相似文献
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The effect of Cl−, HCO3−, Br−, acetazolamide, thiocyanate and amiloride on urine formation in Locusta migratoria Malpighian tubules have been determined. The rate of fluid secretion depends markedly on the concentration of Cl− in the bathing solution with concentrations less than 90 mM resulting in reduced fluid secretion. Substitution of Br− for Cl− had no significant effect on the rate of the fluid secretion. Replacement of NaHCO3 with NaCl in Hepes buffered Ringer solution reduced the rate of urine production by 23%. Fluid secretions were reduced in the presence of 10−4–10−2 M acetazolamide, a carbonic anhydrase inhibitor. The combined effect of acetazolamide in the absence of HCO3− appears to be additive. A 1 mM concentration of thiocyanate, an ionic inhibitor, reduced fluid secretion by 35%. Amiloride interferes with the electrogenic entry of Na+ into the cell and a 1 mM solution reduced fluid secretion by 94% with secretion completely inhibited in 80% of the tubules tested. 相似文献
6.
The objective of this study was to examine membrane filtration of a single stranded DNA (ssDNA) with 60 thymine nucleotides, and to elucidate the variables controlling its transmission across track-etched porous membranes. Dead end filtration measurements were performed using different pore size membranes (10, 15, and 30 nm) at different transmembrane pressures in solutions with ionic strength ranging from 0 to 1000 mM NaCl. The diffusivity of the ssDNA was determined using fluorescence recovery after photobleaching, yielding hydrodynamic radii ranging from 1.6 to 2.8 nm, with values decreasing with increasing solution ionic strength. Despite the small ssDNA/membrane pore size, nearly 100% rejection was observed for measurements performed with the 10 and 15 nm pore size membranes under low-ionic strength conditions. These high rejections can be attributed to strong repulsive electrostatic ssDNA-membrane interactions. With increasing ionic strength, electrostatic interactions as well as the effective size of the ssDNA decreases and the flexibility of the ssDNA increases, leading to a reduction in ssDNA rejection. A design of experiments approach was used to plan filtration experiments that adequately covered the variable space with a manageable number of experiments. The results yielded an empirical expression relating ssDNA rejection to pore size, solution ionic strength and transmembrane pressure. There was evidence of flow induced elongation at high-transmembrane pressures in the 30 nm pore size membranes, but not in the smaller pore size membranes. These results are consistent with critical flux estimates developed using a free draining model for the ssDNA. 相似文献
7.
Indole reacts with sodium nitrite and glycine-HCl buffer, pH 2.6, to form a red color that is stable for more than 1 week. The reaction is reproducible and is linear over a wide range of indole concentrations (0.05–1.00 μmol). Twelve indole derivatives, including tryptophan, and 17 protein amine acids do not interfere. Indole-3-acetic acid, indole-3-acrylic acid, indole-3-pyruvic acid, 5-indole carboxylic acid, and 5-hydroxyindole-3-acetic acid interfere to varying extents (16–27%). Free indole was determined in biological material containing tryptophan by the present method. The method is also applicable to the assay of tryptophanase activity without prior indole extraction. 相似文献
8.
Abdolkarim Moazeni-Roodi Saeid Ghavami Hossein Ansari Mohammad Hashemi 《Journal of cellular biochemistry》2019,120(8):13583-13597
Flap endonuclease 1 (FEN1) has emerged as an important enzyme in the maintenance of genomic instability and preventing carcinogenesis. The relationship between FEN1 −69G>A (rs174538)+4150G>T (rs4246215) polymorphisms and cancer susceptibility has been reported; however, results were inconclusive. In the present study, a meta-analysis of data from eligible reports was carried out to summarize the possible relationship between FEN1 polymorphisms and cancer risk. A total of 11 articles, including 20 studies with 7366 cases and 9028 controls and 18 studies with 6649 cases and 8325 controls for FEN1 rs174538 and FEN1 rs4246215 polymorphisms, respectively, were recruited for meta-analysis. Overall, meta-analyses showed that FEN1 rs174538 and rs4246215 polymorphisms are significantly associated with the decreased risk of cancer. The stratified analysis proposed that both variants were associated with protection against gastrointestinal cancer, breast cancer, hepatocellular cancer, esophageal cancer, gastric cancer, colorectal cancer, and lung cancer. In conclusion, this meta-analysis revealed an association between FEN1 polymorphisms and cancer risk. Additional studies in a larger study population that include subjects from a variety of ethnicities are warranted to further verify our findings. 相似文献
9.
In vitro improvement of quail primordial germ cell expansion through activation of TGF‐beta signaling pathway 下载免费PDF全文
10.
Mashitoh Abd Rahman Faiqah Ramli Hamed Karimian Firouzeh Dehghan Noraziah Nordin Hapipah Mohd Ali Syam Mohan Najihah Mohd Hashim 《PloS one》2016,11(3)
Artonin E is a prenylated flavonoid isolated from the stem bark of Artocarpus elasticus Reinw.(Moraceae). This study aimed to investigate the apoptotic mechanisms induced by artonin E in a metastatic human ovarian cancer cell line SKOV-3 in vitro. MTT assay, clonogenic assay, acridine orange and propidium iodide double staining, cell cycle and annexin V analyses were performed to explore the mode of artonin E-induced cell death at different time points. DNA laddering, activation of caspases-3, -8, and -9, multi-parametric cytotoxicity-3analysis by high-content screening, measurement of reactive oxygen species generation, and Western blot were employed to study the pathways involved in the apoptosis. MTT results showed that artonin E inhibited the growth of SKOV-3 cells, with IC50 values of 6.5±0.5μg/mL after 72 h treatment, and showed less toxicity toward a normal human ovarian cell lineT1074, with IC50 value of 32.5±0.5μg/mL. Results showed that artonin E induced apoptosis and cell cycle arrest at the S phase. This compound also promoted the activation of caspases-3, -8, and -9. Further investigation into the depletion of mitochondrial membrane potential and release of cytochrome c revealed that artonin E treatment induced apoptosis via regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. The expression levels of survivin and HSP70 proteins were also down regulated in SKOV-3 cells treated with artonin E. We propose that artonin E induced an antiproliferative effect that led to S phase cell cycle arrest and apoptosis through dysregulation of mitochondrial pathways, particularly the pro- and anti-apoptosis signaling pathways. 相似文献