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51.
Xue Bin Zheng Misao Tsubokura Yongkun Wang Chun Xie Tetsuji Nagano Kazuhiko Someya Tomoko Kiyohara Kiyomi Suzuki Takeshi Sanekata 《Microbiology and immunology》1995,39(10):821-824
Thirty strains of Yersinia pseudotuberculosis were isolated from rabbits (17 strains), wild rats (9 strains) and house rats (4 strains) in China between 1990 and 1993. The biochemical properties of these isolates were identical with those of Y. pseudotuberculosis and no special characteristics were found in these strains. Serologically, serogroups 4b and 5b were identical to isolates found in Japan, and a new serogroup 1c and unclassified strains have also been detected. The existence of virulence-associated properties were different among strains. The pYV plasmid was detected from 6 strains of 30 isolates. This report documents the presence of Y. pseudotuberculosis in China, providing important epidemiological information. 相似文献
52.
Dissociated sympathetic neurons from the neonatal rat, grown in cell culture in the virtual absence of other cell types, can develop many of the properties expected of differentiated adrenergic neurons including the ability to synthesize and accumulate catecholamines (CA)2. However, in the presence of high concentrations of appropriately conditioned medium (CM), the cultures develop the ability to synthesize and accumulate acetylcholine (ACh); correspondingly, their ability to synthesize CA decreases. In this paper several developmental aspects of the CM effect are described. The time course of development of cultures grown with or without CM was followed using synthesis and accumulation of [3H]CA from [3H]tyrosine and production of [3H]ACh from [3H]choline as assays for adrenergic and cholinergic differentiation. The ability to produce CA or ACh developed along parallel time courses in the two sets of cultures, rising primarily during the second week in vitro and reaching a plateau during the fourth week. When CM was used as a cholinergic developmental signal, the sympathetic neurons showed a decreasing response to addition of CM as they matured adrenergically; addition of CM during the third or fourth 10 days in vitro was not as effective in inducing ACh production as addition during the first or second 10 days. Similarly, removal of CM at various times from cultures previously grown in CM showed that the cholinergic induction caused by CM was not easily reversible in older cultures. Thus, as with the adrenergic decision, the cholinergic decision becomes less reversible as the phenotype becomes fully expressed. 相似文献
53.
Human recombinant stromelysin-1 was shown to cleave four types of collagen (types II, IX, X, and XI) prepared from bovine and rat cartilages at specific sites. Stromelysin-1 cleaved salt-soluble native molecules of type IX collagen into two main triple-helical fragments, COL1 and COL2,3. Protein microsequencing identified the exact cleavage sites in the NC2 domain of all three chains, alpha 1(IX), alpha 2(IX), and alpha 3(IX). Stromelysin-1 also acted as a "telopeptidase," in that it efficiently clipped intact molecules of types II and XI collagens at sites just inside their terminal cross-linking hydroxylysine residues. Native molecules of type X collagen were cleaved by stromelysin-1 within their triple helical domains at a COOH-terminal site that reduced the alpha 1(X) chain size by 10 kDa. These findings suggest an important role for stromelysin in the turnover and remodeling of the collagenous matrix of cartilage both normally and in degenerative joint disease. 相似文献
54.
Ferrous Iron and Sulfur Oxidation and Ferric Iron Reduction Activities of Thiobacillus ferrooxidans Are Affected by Growth on Ferrous Iron, Sulfur, or a Sulfide Ore 总被引:4,自引:3,他引:1 下载免费PDF全文
Isamu Suzuki Travis L. Takeuchi Trin D. Yuthasastrakosol Jae Key Oh 《Applied microbiology》1990,56(6):1620-1626
Eight strains of Thiobacillus ferrooxidans (laboratory strains Tf-1 [= ATCC 13661] and Tf-2 [= ATCC 19859] and mine isolates SM-1, SM-2, SM-3, SM-4, SM-5, and SM-8) and three strains of Thiobacillus thiooxidans (laboratory strain Tt [= ATCC 8085] and mine isolates SM-6 and SM-7) were grown on ferrous iron (Fe2+), elemental sulfur (S0), or sulfide ore (Fe, Cu, and Zn). The cells were studied for their aerobic Fe2+ - and S0-oxidizing activities (O2 consumption) and anaerobic S0-oxidizing activity with ferric iron (Fe3+) (Fe2+ formation). Fe2+-grown T. ferrooxidans cells oxidized S0 aerobically at a rate of 2 to 4% of the Fe2+ oxidation rate. The rate of anaerobic S0 oxidation with Fe3+ was equal to the aerobic oxidation rate in SM-1, SM-3, SM-4, and SM-5, but was only one-half or less that in Tf-1, Tf-2, SM-2, and SM-8. Transition from growth on Fe2+ to that on S0 produced cells with relatively undiminished Fe2+ oxidation activities and increased S0 oxidation (both aerobic and anaerobic) activities in Tf-2, SM-4, and SM-5, whereas it produced cells with dramatically reduced Fe2+ oxidation and anaerobic S0 oxidation activities in Tf-1, SM-1, SM-2, SM-3, and SM-8. Growth on ore 1 of metal-leaching Fe2+-grown strains and on ore 2 of all Fe2+-grown strains resulted in very high yields of cells with high Fe2+ and S0 oxidation (both aerobic and anaerobic) activities with similar ratios of various activities. Sulfur-grown Tf-2, SM-1, SM-4, SM-6, SM-7, and SM-8 cultures leached metals from ore 3, and Tf-2 and SM-4 cells recovered showed activity ratios similar to those of other ore-grown cells. It is concluded that all the T. ferrooxidans strains studied have the ability to produce cells with Fe2+ and S0 oxidation and Fe3+ reduction activities, but their levels are influenced by growth substrates and strain differences. 相似文献
55.
56.
Concanavalin A Receptors Associated with Rat Brain Synaptic Junctions Are High Mannose-Type Oligosaccharides 总被引:1,自引:1,他引:0
Abstract: Glycoproteins were isolated from a rat brain synaptic junction fraction by affinity chromatography on Concanavalin A-agarose. The isolated glycoproteins were digested with pronase and radiolabeled with 125 I-Bolton Hunter reagent, and 125 I-Concanavalin A-binding glycopeptides were isolated by chromatography on Concanavalin A-agarose. Treatment of the 125 I-Concanavalin A-binding glycopeptides with either α-mannosidase or endo-β- N -acetylglucosaminidase-C11 abolished their interaction with Concanavalin A. The pronase digest was reacted with endo-β-N-acetylglucosaminidase-C11 and released oligosaccharides were reduced with NaB3 H4 . Following affinity chromatography on Concanavalin A-agarose, Concanavalin A-binding [3 H]oligosaccharides were chromatographed on Biogel P4 . Two major oligosaccharides corresponding to standard carbohydrates containing eight and five mannose residues were identified. Treatment of these oligosaccharides with α-mannosidase converted them to smaller saccharides having a mobility on Biogel P4 columns equal to the standard disaccharide mannose-β-1-4- N '-acetylglucosamine. These results demonstrate that the Concanavalin A receptor activity associated with CNS synaptic junctions resides in asparaginelinked oligosaccharides of the high-mannose type. 相似文献
57.
The recently-developed large zone difference profile method in scanning molecular sieve chromatography is applied to the analysis of the Gibbs-Duhem expression in the tetramer-dimer equilibrium of human oxyhemoglobin A. The preferential binding term and solvation parameters of the Hofmeister anion phosphate are examined. Results indicate that as the concentration of phosphate ions increase, a hydrated phosphate is formed which enhances the association by perturbing the solvation layer of the hemoglobin molecules. The standard free energy change at a given Hofmeister anion activity of InA(x) = -3.2476 is 9.4 +/- 0.2 kcal mole . DeltaG degrees at InA(x) = -1.2711 is 10.90 +/- 0.05 kcal mole , suggesting that approximately 11 kcal are required to dissociate one mole of tetramer into dimer. 相似文献
58.
ZAKβ antagonizes and ameliorates the cardiac hypertrophic and apoptotic effects induced by ZAKα 下载免费PDF全文
Chien‐Yao Fu Wei‐Wen Kuo Tsung‐Jung Ho Su‐Ying Wen Ling‐Chun Lin Yan‐Shen Tseng Hui‐Chuan Hung Vijaya Padma Viswanadha Chih‐Yang Huang 《Cell biochemistry and function》2016,34(8):606-612
ZAK (sterile alpha motif and leucine zipper containing kinase AZK), a serine/threonine kinase with multiple biochemical functions, has been associated with various cell processes, including cell proliferation, cell differentiation, and cardiac hypertrophy. In our previous reports, we found that the activation of ZAKα signaling was critical for cardiac hypertrophy. In this study, we show that the expression of ZAKα activated apoptosis through both a FAS‐dependent pathway and a mitochondria‐dependent pathway by subsequently inducing caspase‐3. ZAKβ, an isoform of ZAKα, is dramatically expressed during cardiac hypertrophy and apoptosis. The interaction between ZAKα and ZAKβ was demonstrated here using immunoprecipitation. The results show that ZAKβ has the ability to diminish the expression level of ZAKα. These findings reveal an inherent regulatory role of ZAKβ to antagonize ZAKα and to subsequently downregulate the cardiac hypertrophy and apoptosis induced by ZAKα. 相似文献
59.
Munkhtugs Davaatseren Jin-Taek Hwang Jae Ho Park Myung-Sunny Kim Shuaiyu Wang Mi Jeong Sung 《PloS one》2014,9(7)
Allyl isothiocyanate (AITC) is a phytochemical found in cruciferous vegetables that has known chemopreventive and chemotherapeutic activities. Thus far, the antiangiogenic activity of AITC has not been reported in in vivo studies. Herein, we investigated the effect of AITC on angiogenesis and inflammation in a mouse model of colitis. Experimental colitis was induced in mice by administering 3% dextran sulfate sodium via drinking water. To monitor the activity of AITC in this model, we measured body weight, disease activity indices, histopathological scores, microvascular density, myeloperoxidase activity, F4/80 staining, inducible nitric oxide synthase (iNOS) expression, cyclooxygenase-2 (COX-2) expression, and vascular endothelial growth factor (VEGF)-A/VEGF receptor 2 (VEGFR2) expression in the mice. We found that AITC-treated mice showed less weight loss, fewer clinical signs of colitis, and longer colons than vehicle-treated mice. AITC treatment also significantly lessened the disruption of colonic architecture that is normally associated with colitis and repressed the microvascularization response. Further, AITC treatment reduced both leukocyte recruitment and macrophage infiltration into the inflamed colon, and the mechanism these activities involved repressing iNOS and COX-2 expression. Finally, AITC attenuated the expression of VEGF-A and VEGFR2. Thus, AITC may have potential application in treating conditions marked by inflammatory-driven angiogenesis and mucosal inflammation. 相似文献
60.