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1.
Received: 23 June 1993 / Accepted in revised form: 15 September 1994 相似文献
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Kazuo Seta Mitsunori Washitake Toshio Anmo 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,181(3-4)
A 100-μl urine sample was chromatographed on a column packed with a strongly basic macroreticular anion-exchange resin (Diaion CDR-10, 5– μm diameter with a nominal 35% cross linkage). The elution was performed with a linear acetate gradient from 0 to 6.0 M at an average flow-rate of 0.72 ml/min and at an average pressure of 104 kg/cm2. The relative standard deviation of retention times and peak height was ± 4% or less. The properties of the macroreticular anion-exchange resin, the effect of the particle size, the pH of acetate buffers, and the effect of the flow-rate of the eluent on the separation were investigated. Thirty three components of urine were then resolved and named. 相似文献
4.
Interleukin (IL)-6, a cytokine featuring redundancy and pleiotropic activity, contributes to host defense against acute environmental stress, while dysregulated persistent IL-6 production has been demonstrated to play a pathological role in various autoimmune and chronic inflammatory diseases. Targeting IL-6 is thus a rational approach to the treatment of these diseases. Indeed, clinical trials of tocilizumab, a humanized anti-IL-6 receptor antibody have verified its efficacy and tolerable safety for patients with rheumatoid arthritis, Castleman''s disease and systemic juvenile idiopathic arthritis, resulting in approval of this innovative biologic for treatment of these diseases. Moreover, a considerable number of case reports and pilot studies of off-label use of tocilizumab point to the beneficial effects of tocilizumab for a variety of other phenotypically different autoimmune and chronic inflammatory diseases. Elucidation of the source of IL-6 and of mechanisms through which IL-6 production is dysregulated can thus be expected to lead to clarification of the pathogenesis of various diseases. 相似文献
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H. Furuya Yoh-ji Kukita Sukehisa Nagano Yasuyoshi Sakai Yoriaki Yamashita Hidenao Fukuyama Yuichiro Inatomi Yutaka Saito Ryoko Koike Shoji Tsuji Yasuyuki Fukumaki Kenshi Hayashi Takuro Kobayashi 《Human genetics》1997,100(3-4):450-456
We examined galactosylceramidase (GALC) cDNA in four Japanese patients with adult onset globoid cell leukodystrophy (Krabbe
disease; AO-GLD) by polymerase chain reaction/single-strand conformation polymorphism (PCR-SSCP) analysis, subsequent sequence
determination, and restriction enzyme digestion of PCR products. Initial symptoms were the onset of slowly progressive spastic
paraplegia from the middle of the second decade, and all patients had diminished GALC activity in their leukocytes. We identified
three missense mutations (I66M, G270D, L618S) and one exon-6 skipping (535– 573del). Two of the patients had only the I66M
mutant mRNA, and one only the G270D mutant mRNA. The fourth patient carried a compound heterozygous mutation of 535–573del
and L618S. To determine the enzymatic activities produced by these mutations, we constructed mutated GALC cDNAs and expressed
them in COS-1 cells. Three mutations, viz., G270D, L618S, and exon-6 skipping (535–573del), produced diminished GALC activity
as expected. The I66M mutation in the wild-type GALC cDNA(I289) had normal activity, but when this mutation and the V289 polymorphism
were introduced into the same allele, it had decreased activity. Thus, the combination of a unique mutation and polymorphism
causes conformational change in the GALC enzyme, resulting in low enzymatic activity. AO-GLD mutations, including those found
here, are located in the N-terminus (I66M, G270D, 535–573del) or C-terminus (L618S) of the GALC enzyme, whereas the reported
mutations in the infantile form (IF-GLD) are in the central domain. This difference in mutation sites may affect the clinical
features of GLD.
Received: 4 February 1997 / Accepted: 28 April 1997 相似文献
8.
The location of the dissimilatory nitrite reductase and orientation of its reducing site of the Grampositive denitrifier, Bacillus firmus NIAS 237 were examined. Approximately 90% of the total dissimilatory nitrite reductase activity with ascorbate-reduced phenazine methosulfate (PMS) as the electron donor was on the protoplast membrane. Nitrite induced with intact Bacillus cells an alkalinization in the external medium, followed by acidification. The electron transfer inhibitor, 2-heptyl-4-hydroxyquinoline-N-oxide, which blocked nitrite reduction with endogenous substrates, inhibited the acidification, but not the alkalinization. Alkalinization was not affected with ascorbate-reduced PMS as the artificial electron donor. This indicated that the alkalinization is not associated with proton consumption outside the cytoplasmic membrane by the extracellular nitrite reduction. The dissimilatory nitrite reductase of B. firmus NIAS 237 was located on the cytoplasmic membrane, and its reducing site is suggested to be on the inner side of this membrane.Abbreviations CCCP
carbonylcyanide m-chlorophenylhydrazone
- HOQNO
2-heptyl-4-hydroxyquinoline-N-oxide
- PMS
phenazine methosulfate
- H+/NO
inf2
sup-
ratio
number of consumed protons in the external medium per one ion of NO
inf2
sup-
reduced 相似文献
9.
Molecular characterization of an adenylate cyclase gene of the cyanobacterium Spirulina platensis 总被引:4,自引:0,他引:4
A cyaA gene, encoding an adenylate cyclase, was isolated from a filamentous cyanobacterium, Spirulina platensis, by functional complementation of a cya mutant of Escherichia coli, defective in adenylate cyclase activity. The predicted gene product of cyaA contains a signal peptide-like domain, a putative sensor domain similar to the gene product of vsrA of Pseudomonas solanacearum, a putative membrane-spanning domain and an adenylate cyclase-like catalytic domain. Two other positive clones that complemented the E. coli mutant were isolated from the same cyanobacterium, suggesting that several cya genes are functioning in S. platensis. 相似文献
10.
Seigo Sato Toshio Yajima Sukekuni Mukataka Joji Takahashi 《Biotechnology Techniques》1995,9(6):383-388
Summary Repeated batch hydrolysis of casein using immobilized protease were carried out at various do tensions and pH. At any of the pH tested, microbial contamination could be satisfactorily suppressed by maintaining high do. In continuous reaction, contamination could be suppressed throughout 40 days under the do of 190 ppm, whereas contamination was observed after 24 hours with the do of 2.5 ppm. 相似文献