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991.
Apoptosis is a step of the cell cycle which is important in the regulation of immune cell populations. Chungkookjang is a Korean traditional fermented soybean containing microorganisms, enzymes, and bioactive compounds which was used in the treatment of mouse spleen as well as thymus cells (CH1-fermented soybean containing barley, wormwood, and sea tangle; CH2-fermented soybean) and was found to exhibit substantially reduced small DNA fragmentation. An MTT assay showed that the treatment of CH1 and CH2 into the mouse splenocytes and thymocytes sharply increased their survival. Moreover, a FACS analysis also showed that CH1 and CH2 are effective at suppressing the apoptosis of splenocytes and thymocytes. The fermented soybean isoflavone concentrations, which are implicated in lowering breast and prostate cancers, lowering the risk of cardiovascular diseases, and improving bone health, were determined using Capillary Electrophoresis-Electrochemical Detection (CE-ED). The amount of Daidzein in fermented soybean significantly increased by 44-fold dramatically, compared with those in unfermented soybean. In this study, we demonstrated that ethanol extracts of Chungkookjang promote the survival of the mouse spleen and thymus cells in culture by suppressing their apoptotic death. Future studies should investigate which genes are related to apoptosis of the immune cells.  相似文献   
992.
Burkholderia sp. HY-10 isolated from the digestive tracts of the longicorn beetle, Prionus insularis, produced an extracellular lipase with a molecular weight of 33.5 kDa estimated by SDS-PAGE. The lipase was purified from the culture supernatant to near electrophoretic homogenity by a one-step adsorption-desorption procedure using a polypropylene matrix followed by a concentration step. The purified lipase exhibited highest activities at pH 8.5 and 60 degrees . A broad range of lipase substrates, from C4 to C18 rho-nitrophenyl esters, were hydrolyzed efficiently by the lipase. The most efficient substrate was rho-nitrophenyl caproate (C6). A 2485 bp DNA fragment was isolated by PCR amplification and chromosomal walking which encoded two polypeptides of 364 and 346 amino acids, identified as a lipase and a lipase foldase, respectively. The N-terminal amino acid sequence of the purified lipase and nucleotide sequence analysis predicted that the precursor lipase was proteolytically modified through the secretion step and produced a catalytically active 33.5 kDa protein. The deduced amino acid sequence for the lipase shared extensive similarity with those of the lipase family I.2 of lipases from other bacteria. The deduced amino acid sequence contained two Cystein residues forming a disulfide bond in the molecule and three, well-conserved amino acid residues, Ser131, His330, and Asp308, which composed the catalytic triad of the enzyme.  相似文献   
993.
We have isolated previously three synthetic lethal mutants in Schizosaccharomyces pombe, which genetically interact with mex67, in order to identify the genes involved in mRNA export. A novel nup97 gene was isolated by complementation of the growth defect in one of the synthetic lethal mutants, SLMex3. The nup97 gene contains one intron and encodes an 851 amino-acid protein that is similar to nucleoporins, Npp106p in S. pombe and Nic96p in Saccharomyces cerevisiae. The nup97 gene is essential for vegetative growth, and nup97 null mutant harboring pREP41X-Nup97 showed poly(A)+ RNA export defect when expression of nup97 is repressed in the presence of thiamine. These results suggest that nup97 is involved in mRNA export from the nucleus to cytoplasm.  相似文献   
994.
The new technology, two-dimensional difference gel electrophoresis (2D DIGE), uses fluorescent dyes to simplify the process of detecting and matching proteins between multiple gels by allowing for the separation of up to three separate protein samples within the same gel. In this study, recombinant human cytotoxic T lymphocyte-associated antigen 4-immunoglobulin (hCTLA4lg) was produced in transgenic rice suspension cell cultures and the intracellular proteins were analyzed by 2D DIGE. The highest level of hCTLA4Ig (25.4 mg/L) was obtained five days after induction. The intracellular proteins expressed at both the growth and induction culture stages were separated and analyzed using DeCyder software. At least 2,218 spots were detected with two-fold thresholds and 95% confidence. We found that 29 spots increased and 20 spots decreased in their intensities during the production of recombinant hCTLA4Ig. In addition, the 2D Western blot of hCTLA4Ig revealed that this fusion protein was expressed in a variety of isoforms.  相似文献   
995.
Members of the cyclophilin (Cyp) family are known to function as co-chaperones, interacting with chaperones such as heat shock protein 90, and perform important roles in protein folding under high temperature stress. In addition, they have been isolated from a wide range of organisms. However, there have been no reports on the functions of algal Cyps under other stress conditions. To study the functions of the cDNAGjCyp-1 isolated from the red alga (Griffithsia japonica), a recombinant GjCyp-1 containing a hexahistidine tag at the amino-terminus was constructed and expressed inEscherichia coli. Most of the gene product expressed inE. coli was organized as aggregate insoluble particles known as inclusion bodies. Thus, the optimal time, temperature, and concentration ofl(+)-arabinose for expressing the soluble and nonaggregated form of GjCyp-1 inE. coli were examined. The results indicate that the induction of Cyp, at 0.2%l(+)-arabinose for 2 h at 25°C, had a marked effect on the yield of the soluble and active form of the co-chaperone as PPlase. An expressed fusion protein, H6GjCyp-1, maintained the stability ofE. coli proteins up to-75°C. In a functional bioassay of the recombinant H6GjCyp-1, the viability ofE. coli cells overexpressing H6GjCyp-1 was compared to that of cells not expressing H6GjCyp-1 at −75°C. For all the cycles of a freeze/thaw treatment, a significant increase in viability was observed in theE. coli cells overexpressing H6GjCyp-1. The results of the GjCyp-1 bioassays, as well asin vitro studies, strongly suggest that the algal Cyp confers freeze tolerance toE. coli.  相似文献   
996.
BACKGROUND/AIM: Although transplantation of MSC derived from bone marrow or adipose tissues has been shown in proangiogenic action in hindlimb ischemia model of nude mice, little information is available regarding comparison of the angiogenic potency between human adipose stromal cells (hADSC) and bone marrow stromal cells (hBMSC). We compared their therapeutic potential by transplantation of equal numbers of hADSC or hBMSC in a nude mice model of hindlimb ischemia. METHODS AND RESULTS: One day after creating hindlimb ischemia, mice were randomized to receive hADSC transplantation (hADSC group), hBMSC transplantation (hBMSC group), or vehicle transplantation (Control group). Two weeks after transplantation, the laser Doppler perfusion index was significantly higher in the hADSC group and hBMSC group than in the control group. Comparison between hADSC and hBMSC group showed better recovery of blood flow in hADSC group than in hBMSC group. Conditioned media from hADSC (hADSC-CM) showed better in vitro tube formation of hADSC than conditioned media from hBMSC (hBMSC-CM). hADSC showed higher expression of MMP3 and MMP9 than hBMSC. A MMP inhibitor, GM6001, and the transfection of MMP3 or MMP9 siRNA oligonucleotides inhibited in vitro tube formation of hADSC. Transplantation of MMP3 or MMP9 siRNA oligonucleotieds-transfected hADSC showed lower blood flow recovery and higher tissue injury than control oligonucelotide-transfected cells. CONCLUSION: This study showed that hADSC can be an ideal source for therapeutic angiogenesis in ischemic disease in terms of efficacy, accessibility and available tissue amounts.  相似文献   
997.
998.
Recently, quorum sensing has been implicated as an important global regulator controlling the production of numerous virulence factors such as capsular polysaccharides in bacterial pathogens. The nucleotide and deduced amino acid sequences of smcR, a homolog of V. harveyi luxR identified from V. vulnificus ATCC29307, were analyzed. The amino acid sequence of SmcR from V. vulnificus was 72 to 92% similar to those of LuxR homologs from Vibrio spp. Functions of SmcR were assessed by the construction of an isogenic mutant, whose smcR gene was inactivated by allelic exchanges, and by evaluating its phenotype changes in vitro and in mice. The disruption of smcR resulted in a significant alteration in biofilm formation, in type of colony morphology, and in motility. When compared with the wild-type, the smcR mutant exhibited reduced survival under adverse conditions, such as acidic pH and hyperosmotic stress. The smcR mutant exhibited decreased cytotoxic activity toward INT 407 cells in vitro. Furthermore, the intraperitoneal LD50 of the smcR mutant was approximately 10(2) times higher than that of parental wild-type. Therefore, it appears that SmcR is a novel global regulator, controlling numerous genes contributing to the pathogenesis as well as survival of V. vulnificus.  相似文献   
999.
Beta-1,3-glucans enhance immune reactions such as antitumor, antibacterial, antiviral, anticoagulatory, and wound healing activities. beta-1,3-Glucans have various functions depending on the molecular weight, degree of branching, conformation, water solubility, and intermolecular association. The molecular weight of the soluble glucan was about 15,000 as determined by a high-performance size exclusion chromatography. From the infrared (IR) and 13C NMR analytical data, the purified soluble glucan was found to exclusively consist of beta-D-glucopyranose with 1,3 linkage. We tested the immunestimulating activities of the soluble beta-1,3-glucan extracted from Agrobacterium sp. R259 KCTC 1019 and confirmed the following activities. IFN-gamma and each cytokines were induced in the spleens and thymus of mice treated with soluble beta-1,3-glucan. Adjuvant effect was observed on antibody production. Nitric oxide was synthesized in monocytic cell lines treated with beta-1,3-glucan. The cytotoxic and antitumor effects were observed on various cancer cell lines and ICR mice. These results strongly suggested that this soluble beta-1,3-glucan could be a good candidate for an immune-modulating agent.  相似文献   
1000.
Microorganisms capable of degrading crude oil were isolated and grown in soybean oil as a sole carbon source. The microbial cultures were used to control green peach aphids in vitro. Approximately 60% mortality of aphids was observed when the cultures were applied alone onto aphids. To examine the cultures as a pesticide formulation mixture, the cultures were combined with a low dose of the insecticide imidacloprid (one-fourth dose of recommended field-application rate) and applied onto aphids. The cultures enhanced significantly the insecticidal effectiveness of imidacloprid, which was higher than imidacloprid alone applied at the low dose. The isolated microorganisms exhibited high emulsifying index values and decreased surface tension values after being grown in soybean oil media. GC/MS analyses showed that microorganisms degraded soybean oil to fatty acids. The cultures were suggested to play the roles of wetting, spreading, and sticking agents to improve the effectiveness of imidacloprid. This is the first report on the control of aphids by using oil-degrading microbial cultures.  相似文献   
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