The interaction between β-K 4H 3 [SiW 9O 37(CpTi) 3]·11H 2O and DNA was investigated by agarose gel electrophoresis. The results suggest that β-K 4H 3[SiW 9O 37(CpTi) 3]·11H 2O can degrade the genomic DNA....The interaction between β-K 4H 3 [SiW 9O 37(CpTi) 3]·11H 2O and DNA was investigated by agarose gel electrophoresis. The results suggest that β-K 4H 3[SiW 9O 37(CpTi) 3]·11H 2O can degrade the genomic DNA. The treatment of plasmid DNA with β-K 4H 3 [SiW 9O 37(CpTi) 3]·11H 2O resulted in a fast moving band in front of the three normal conformations(super coiled DNA, linear DNA and relaxed circular DNA) in agarose gel electrophoresis . These results indicate that this chemical material may have the ability to specifically cleavage DNA or to alter conformation of DNA molecules.展开更多
Background: Recently micro-organisms that synthesize extended-spectrum β-lactamase (ESBLs) were increased. The peculiarities of ESBL synthesis of Escherichia coli and Klebsiella pneumoniae strains that cause nosocomi...Background: Recently micro-organisms that synthesize extended-spectrum β-lactamase (ESBLs) were increased. The peculiarities of ESBL synthesis of Escherichia coli and Klebsiella pneumoniae strains that cause nosocomial urinary tract infections, surgical site infections and pneumonia in surgical clinic were studied. ESBL synthesis were observed 38.9% of E. coli strains obtained from urine, 92.3% of strains obtained from surgical site infections, and 50% of strains obtained from sputum. ESBL synthesis were observed 37.5% of K. pneumoniae strains obtained from urine, 85.7% of strains obtained from surgical site infections, and 60% of strains obtained from sputum. Different levels of ESBL synthesize of E. coli and K. pneumoniae strains isolated from different pattern is discussed. Conclusion. ESBL synthesis is common in E. coli and K. pneumoniae strains, which cause nosocomial infections. The frequency of occurrence of ESBL s synthesis among of these strains depends on clinical forms of nosocomial infections.展开更多
Hyperkalemia is one of the most important risk factors in patients suffering from crush syndrome with rhabdomyolysis. Glycerol-injected animals have been used as an experimental model of rhabdomyolysis-induced acute k...Hyperkalemia is one of the most important risk factors in patients suffering from crush syndrome with rhabdomyolysis. Glycerol-injected animals have been used as an experimental model of rhabdomyolysis-induced acute kidney injury (AKI), but little information is available for the onset and molecular mechanism of hyperkalemia. In our murine model, plasma potassium levels increased after a single injection of 50%-glycerol solution (10 ml/kg, i.m.) during the progression of muscular and renal injuries. Renal tubular Na<sup>+</sup>-K<sup>+</sup>-ATPase functions as ion-exchange pomp for potassium clearance from blood into renal tubular epithelial cells. Renal histochemistry revealed an apparent decrease in the tubular Na<sup>+</sup>-K<sup>+</sup>-ATPase expression, especially at 24 hours post-glycerol challenge in our AKI model. In contrast to the loss in active Na+-K+-ATPase, there was a significant increase in the renal levels of transforming growth factor-β (TGF-β) that is known to suppress Na<sup>+</sup>-K<sup>+</sup>-ATPase production in vitro. When anti-TGF-β antibody was administered in mice after the glycerol challenge, the suppression of renal Na<sup>+</sup>-K<sup>+</sup>-ATPase activity was partially restored. As a result, hyperkalemia was improved in the TGF-β-neutralized AKI mice, associated with a significant decrease in plasma potassium concentration. Taken together, we predict that endogenous TGF-β is a key regulator for inhibiting Na<sup>+</sup>-K<sup>+</sup>-ATPase production and, in part, enhancing hyperkalemia during progression of rhabdomyolysis-induced AKI. This is, to our knowledge, the first report to determine a critical role of endogenous TGF-β in renal potassium metabolism during crush syndrome.展开更多
A mutant strain T199 producing about 8 times as much β-glucanase as its parent strain trichoderma kningii T3 was obtained by treatment with ultraviolet light and N-methyl-N-nitro-N-nitrosoguanidine.Fermentation was...A mutant strain T199 producing about 8 times as much β-glucanase as its parent strain trichoderma kningii T3 was obtained by treatment with ultraviolet light and N-methyl-N-nitro-N-nitrosoguanidine.Fermentation was conducted in 250mL flask,each containing 30mL of medium consisted of 5% corn cob powder,3% wheat bran and 1.4% nitrogen source No.10 ((NH 4) 2SO 4 10%,Peptone 20%,Yeast extract 15%).The optima culture conditions were as below:initial pH5.0,30℃,shaking speed 280r/min,and cultivation time 5d.Enzyme activity toward CMC-Na,lichenin,laminarin and barley β-glucan at pH 5.0 and 60℃ for 10min were 300,1100,12 and 1600 IU/mL,respectively.The optima pH and temperature for enzyme action toward barley β-glucan were pH 5.0 and 70℃,respectively.The enzyme was stable under below 50℃ and at pH 4.5～6.5.展开更多
文摘The interaction between β-K 4H 3 [SiW 9O 37(CpTi) 3]·11H 2O and DNA was investigated by agarose gel electrophoresis. The results suggest that β-K 4H 3[SiW 9O 37(CpTi) 3]·11H 2O can degrade the genomic DNA. The treatment of plasmid DNA with β-K 4H 3 [SiW 9O 37(CpTi) 3]·11H 2O resulted in a fast moving band in front of the three normal conformations(super coiled DNA, linear DNA and relaxed circular DNA) in agarose gel electrophoresis . These results indicate that this chemical material may have the ability to specifically cleavage DNA or to alter conformation of DNA molecules.
文摘Background: Recently micro-organisms that synthesize extended-spectrum β-lactamase (ESBLs) were increased. The peculiarities of ESBL synthesis of Escherichia coli and Klebsiella pneumoniae strains that cause nosocomial urinary tract infections, surgical site infections and pneumonia in surgical clinic were studied. ESBL synthesis were observed 38.9% of E. coli strains obtained from urine, 92.3% of strains obtained from surgical site infections, and 50% of strains obtained from sputum. ESBL synthesis were observed 37.5% of K. pneumoniae strains obtained from urine, 85.7% of strains obtained from surgical site infections, and 60% of strains obtained from sputum. Different levels of ESBL synthesize of E. coli and K. pneumoniae strains isolated from different pattern is discussed. Conclusion. ESBL synthesis is common in E. coli and K. pneumoniae strains, which cause nosocomial infections. The frequency of occurrence of ESBL s synthesis among of these strains depends on clinical forms of nosocomial infections.
文摘Hyperkalemia is one of the most important risk factors in patients suffering from crush syndrome with rhabdomyolysis. Glycerol-injected animals have been used as an experimental model of rhabdomyolysis-induced acute kidney injury (AKI), but little information is available for the onset and molecular mechanism of hyperkalemia. In our murine model, plasma potassium levels increased after a single injection of 50%-glycerol solution (10 ml/kg, i.m.) during the progression of muscular and renal injuries. Renal tubular Na<sup>+</sup>-K<sup>+</sup>-ATPase functions as ion-exchange pomp for potassium clearance from blood into renal tubular epithelial cells. Renal histochemistry revealed an apparent decrease in the tubular Na<sup>+</sup>-K<sup>+</sup>-ATPase expression, especially at 24 hours post-glycerol challenge in our AKI model. In contrast to the loss in active Na+-K+-ATPase, there was a significant increase in the renal levels of transforming growth factor-β (TGF-β) that is known to suppress Na<sup>+</sup>-K<sup>+</sup>-ATPase production in vitro. When anti-TGF-β antibody was administered in mice after the glycerol challenge, the suppression of renal Na<sup>+</sup>-K<sup>+</sup>-ATPase activity was partially restored. As a result, hyperkalemia was improved in the TGF-β-neutralized AKI mice, associated with a significant decrease in plasma potassium concentration. Taken together, we predict that endogenous TGF-β is a key regulator for inhibiting Na<sup>+</sup>-K<sup>+</sup>-ATPase production and, in part, enhancing hyperkalemia during progression of rhabdomyolysis-induced AKI. This is, to our knowledge, the first report to determine a critical role of endogenous TGF-β in renal potassium metabolism during crush syndrome.
文摘A mutant strain T199 producing about 8 times as much β-glucanase as its parent strain trichoderma kningii T3 was obtained by treatment with ultraviolet light and N-methyl-N-nitro-N-nitrosoguanidine.Fermentation was conducted in 250mL flask,each containing 30mL of medium consisted of 5% corn cob powder,3% wheat bran and 1.4% nitrogen source No.10 ((NH 4) 2SO 4 10%,Peptone 20%,Yeast extract 15%).The optima culture conditions were as below:initial pH5.0,30℃,shaking speed 280r/min,and cultivation time 5d.Enzyme activity toward CMC-Na,lichenin,laminarin and barley β-glucan at pH 5.0 and 60℃ for 10min were 300,1100,12 and 1600 IU/mL,respectively.The optima pH and temperature for enzyme action toward barley β-glucan were pH 5.0 and 70℃,respectively.The enzyme was stable under below 50℃ and at pH 4.5～6.5.
