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441.
An extracellular thermostable alkaline serine protease enzyme from Aeribacillus pallidus C10 (GenBank No: KC333049), was purified 4.85 and 17. 32-fold with a yield of 26.9 and 19.56%, respectively, through DE52 anion exchange and Probond affinity chromatography. The molecular mass of the enzyme was determined through sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), with approximately 38.35?kDa. The enzyme exhibited optimum activity at pH 9 and at temperature 60?°C. It was determined that the enzyme had remained stable at the range of pH 7.0–10.0, and that it had preserved more than 80% of its activity at a broad temperature range (20–80?°C). The enzyme activity was found to retain more than 70% and 55% in the presence of organic solvents and commercial detergents, respectively. In addition, it was observed that the enzyme activity had increased in the presence of 5% SDS. KM and Vmax values were calculated as 0.197?mg/mL and 7.29?μmol.mL?1.min?1, respectively.  相似文献   
442.
In this research, protease enzyme was purified and characterized from milk of Euphorbia amygdaloides. (NH4)2SO4 fractionation and CM-cellulose ion exchange chromatography methods were used for purification of the enzyme. The optimum pH value was determined to be 5, and the optimum temperature was determined to be 60 degrees C. The V(max) and K(M) values at optimum pH and 25 degrees C were calculated by means of Linewearver-Burk graphs as 0.27 mg/L min(-1) and 16 mM, respectively. The purification degree was controlled by using SDS-PAGE and molecular weight was found to be 26 kD. The molecular weight of the enzyme was determined as 54 kD by gel filtration chromatography. These results show that the enzyme has two subunits.In the study, it was also researched whether purified and characterized protease can be collapsed to milk. It was determined that protease enzyme can collapse milk and it can be used to produce cheese.  相似文献   
443.

Background  

We have examined the evolution of the genes at the major human β-defensin locus and the orthologous loci in a range of other primates and mouse. For the first time these data allow us to examine selective episodes in the more recent evolutionary history of this locus as well as the ancient past. We have used a combination of maximum likelihood based tests and a maximum parsimony based sliding window approach to give a detailed view of the varying modes of selection operating at this locus.  相似文献   
444.
Recent studies have demonstrated the utility of recombinant adeno-associated viral (rAAV) vectors in the generation of human knockout cell lines. The efficiency with which such cell lines can be generated using rAAV, in comparison with more extensively described plasmid-based approaches, has not been directly tested. In this report, we demonstrate that targeting constructs delivered by rAAV vectors were nearly 25-fold more efficient than transfected plasmids that target the same exon. In addition, we describe a novel vector configuration which we term the synthetic exon promoter trap (SEPT). This targeting element further improved the efficiency of knockout generation and uniquely facilitated the generation of knockin alterations. An rAAV-based SEPT targeting construct was used to transfer a mutant CTNNB1 allele, encoding an oncogenic form of β-catenin, from one cell line to another. This versatile method was thus shown to facilitate the efficient integration of small, defined sequence alterations into the chromosomes of cultured human cells.  相似文献   
445.
Cyromazine seed treatments were evaluated for onion maggot control in green onion crops. The more tolerant to organophosphates of two populations of onion maggots was chosen for further research, based on the results of adult assays in a Potter spray tower. In the laboratory, first-instar mortality was compared between film-coated seed treatment and soil drench treatment. The LC50 for the film-coated seed treatment was approximately one fourth that of the soil drench treatment. In choice assays, no significant difference was observed between the number of eggs deposited on seedlings grown from film-coated seeds with cyromazine and film-coated seeds without cyromazine. Field studies demonstrated that all rates of cyromazine seed treatment resulted in protection of onion plants from onion maggot damage. Green onions may not require as high a rate of cyromazine for control of onion maggots as the rate established for use in dry onions for two reasons: the seeding rate is much higher for green onions resulting in more AI/ha for a given amount of AI/kg of seed, and a given percentage of stand loss is more difficult to detect in green onions than in dry onions.  相似文献   
446.
In the present study streptococci of serological group B isolated from canines (n=48) and felines (n=7) were comparatively investigated with group B streptococci from humans and bovines for cultural, biochemical and serological properties for antibiotic resistancies and by molecular analysis. An identification was performed with group B-specific antiserum, biochemical reactions, by PCR amplification and subsequent endonuclease digestion of the 16S rRNA gene and by amplification of species-specific parts of the 16S rDNA the 16S-23S rDNA intergenic spacer region and the CAMP factor gene cfb. Phenotypic similarities of group B streptococci of canine and feline origin with group B streptococci from humans and differences to group B streptococci of bovine origin could be observed in lactose fermentation, serotype patterns, pigmentation, growth properties of the bacteria in fluid medium and soft agar, hemagglutination reactions and in minocycline and tetracycline resistance. A negative hyaluronidase plate test, a hylB amplicon with a size of 4.6 kb and an insertion sequence 1548 could be observed among canine, feline and human group B streptococci of serotype III. The remaining hyaluronidase positive strains, also including all isolates of bovine origin, had a hylB gene with a size of 3.3 kb. Further genotypic differences could be observed in the occurrence of the genes lmb and scpB which appeared generally among canine, feline and human group B streptococci, but less pronounced among bovine isolates of this species. According to the presented data group B streptococci of canine and feline origin seemed to be more related to human than to bovine isolates of this species possibly indicating some epidemiological relation.  相似文献   
447.
The effect of cobalt(II) chloride (CoCl2) and CoCl2 with ascorbic acid (AA) on components of the antioxidant defense system and lipid oxidative damage were studied in controls and streptozotocin-induced diabetic rat livers. Three days after injection, rats received either 0.5 mM CoCl2 or 0.5 mM CoCl2 with a combination of 1 g/L AA in drinking water up to 6 wk. The elevated blood glucose levels in diabetic rats were about 12% restored by oral administration of CoCl2 (0.05 mM) and were significant reduced (46%) following AA addition (1 g/L) to CoCl2. Cobalt therapy effectively decreased the increased activities of catalase (CAT), superoxide dismutase (SOD), and thiobarbituric acid reactant substances (TBARS) but could not restore the increased glutathione peroxidase (GSH-Px) in the liver of diabetic rats. Our findings suggest that cobalt therapy may prove effective in improving the impaired antioxidant status during the early state of diabetes, and ascorbic acid supplementation at this dose potentiates the effectiveness of cobalt action.  相似文献   
448.
Various protocols may be used for acute pancreatitis treatment. Recently, the benefit of hyperbaric oxygen (HBO) has been demonstrated. To clarify the mechanism of HBO on the process of the acute pancreatitis, we determined the levels of antioxidant enzymes in an acute pancreatitis model. Forty-five Sprague-Dawley rats were randomly divided into three groups: Group I: sham group (n=15), Group II: pancreatitis group (n=15), Group III: pancreatitis group undergoing HBO therapy (n=15). HBO was applied postoperatively for 5 days, two sessions per day at 2.5 fold absolute atmospheric pressure (ATA) for 90 min. Superoxide dismutase (Cu/Zn-SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH Px) activity were measured in pancreatic tissue and erythrocyte lysate. MDA and GSH Px were also determined in plasma. In addition, amylase levels were measured in the serum. While serum amylase levels and MDA values in erythrocyte, plasma and pancreatic tissue were decreased, the levels of GSH Px and SOD were found to be significantly increased in the Group III as compared to those of the Group II. The findings of our study suggest that HBO has beneficial effects on the course of acute pancreatitis and this effect may occur through the antioxidant systems.  相似文献   
449.

Background

Invasive Aspergillus infections are frequently seen in immunocompromised patients but arthritis is a rare complication of Aspergillus infections in the absence of immune suppressive therapy, trauma or surgical intervention.

Case presentation

A 17 years old male patient with arthritis and patellar osteomyelitis of the left knee whose further investigations revealed chronic granulomatous disease as the underlying disease is followed. Aspergillus fumigatus was isolated from the synovial fluid and the tissue samples cultures. He was treated with Amphotericin B deoxicolate 0.7 mg/kg/day. Also surgical debridement was performed our patient. Amphotericin B nephrotoxicity developed and the therapy switched to itraconazole 400 mg/day. Itraconazole therapy were discontinued at the 6th month. He can perform all the activities of daily living including.

Conclusion

We think that, chronic granulomatous disease should be investigated in patients who have aspergillar arthritis and osteomyelitis.  相似文献   
450.
Kinetoplastida are protozoan organisms that probably diverged early in evolution from other eukaryotes. They are characterized by a number of unique features with respect to their energy and carbohydrate metabolism. These organisms possess peculiar peroxisomes, called glycosomes, which play a central role in this metabolism; the organelles harbour enzymes of several catabolic and anabolic routes, including major parts of the glycolytic and pentosephosphate pathways. The kinetoplastid mitochondrion is also unusual with regard to both its structural and functional properties.  相似文献   
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