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1.
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
2.
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
3.
4.
We documented changes in morphology and gene expression of the renal epithelial cell line A6 derived from Xenopus leavis adult kidney induced by long-term culturing with three dimensional clinostats. An oligo microarray analysis on A6 cells showed that mRNA levels of 52 out of 8091 genes were significantly altered in response to clinorotation. Upregulation or downregulation of gene expression became evident on day 8 and day 10 while there was no significant change on day 5. However, on day 15, expression of 18 out of 52 genes resumed to the levels similar to its original levels while remaining 33 genes maintained altered levels of expression. Quantitative analyses of gene expression by real-time PCR confirmed that changes in mRNA levels of selected genes were found only under clinorotation but not under hypergravity (7 G) and ground control (1 G). Morphological changes including loss of dome-like structures, disassembly of E-cadherin adherence junctions and disassembly of cortical actin were also observed over 10 days of culturing with clinorotation. The results revealed genes which expression was altered specifically in A6 cells cultured under clinorotation. 相似文献
5.
Andoh Tomio; Itoh Hideki; Watanabe Itaru; Sasaki Toshio; Higashi Tomoko 《American journal of physiology. Cell physiology》2001,281(6):C1871
Substance P is known to modulate neuronal nicotinicacetylcholine receptors (nAChRs) in the sympathetic nervous system.There are two conflicting proposals for the mechanism of this effect, an indirect action mediated by protein kinase C (PKC) and a direct interaction with receptor subunits. We studied the mechanisms of thiseffect in PC-12 cells. Substance P enhanced the decay of thenicotine-induced whole cell current. This effect was fast in its onsetand was not antagonized by guanosine5'-O-(2-thiodiphosphate), a G protein blocker, orstaurosporine, a nonselective PKC blocker. Staurosporine failed toreverse the inhibition by 1-oleoyl-2-acetyl-sn-glycerol (OAG), a synthetic diacylglycerol analog known to activate PKC. Theinhibitory effects of the peptide and OAG were preserved in excisedpatches, but substance P applied to the extra patch membrane wasineffective in the cell-attached patch configuration. We conclude thatsubstance P modulates neuronal nAChRs most likely by direct interactions with the receptors but independently from activation ofPKC or G proteins and that PKC does not participate in modulation by OAG. 相似文献
6.
The rate and period of DNA synthesis during meiotic prophasewere examined using lily microsporocytes. Meiocytes at the earlyleptotene stage were cultured for discrete periods in the presenceof inhibitors of DNA synthesis, deoxyadenosine and nalidixicacid. Deoxyadenosine, which arrests meiotic development at theearly zygotene stage, markedly suppressed DNA synthesis to 35%of control at 2 mM. Nalidixic acid simply reduced the rate ofDNA synthesis, resulting in prolongation of the synthetic period.The relevance of DNA synthesis to meiotic development is discussed. (Received January 12, 1987; Accepted May 7, 1987) 相似文献
7.
Atsuko Matsuoka Akiko Hirosawa Shinasku Natori Shigeo Iwasaki Toshio Sofuni Motoi Ishidate Jr. 《Mutation research》1989,215(2):179-185
The chromosomal aberration test using a Chinese hamster lung cell line (CHL) was carried out on ptaquiloside and its related compounds, hypoloside B, hypoloside C, illudin M and illudin S. Ptaquiloside induced chromosomal aberrations at doses as low as 4.5 μg/ml (0.0113 mM). The clastogenic effect was ph-dependent. The same activity was observed at a 90-fold higher dose at pH 5.3 in the culture medium compared with the activity at pH 74. or pH 8.0. Both hypoloside B and hypoloside C were also clastogenic at almost the same dose levels as that of ptaquiloside. Illudin M and illudin S were also potet clastogens and induced aberrations at much lower doses than ptaquiloside. These results suggest that the clastogenic effect is involved in the mechanism of carcinogenic potency of ptaquiloside in animals. 相似文献
8.
Takeshi Tsunetoshi Atsuhiro Otsuka Hiroshi Mikami Katsuhiko Kohara Katsutoshi Katahira Toshio Ogihara 《European journal of applied physiology and occupational physiology》1989,58(7):705-709
We have previously demonstrated that blood pressure elevation by acute blood volume expansion is volume-dependent during the infusion period and resistance-dependent in the post-infusion period in normal anesthetized dogs, and that such an increase in blood pressure is associated with a potentiation of the pressor response to norepinephrine. To evaluate the possible renal contribution to these hemodynamic changes, blood volume expansion was performed for 1 h with dextran dissolved in lactated Ringer's solution (20 ml/kg) in 15 nephrectomized dogs. The mean blood pressure, cardiac output and total peripheral resistance at the end of infusion were 126%, 225% and 60%, respectively; 3 h after volume expansion they were 126%, 151%, and 92% respectively. However, in 4 dogs, there was an increase in mean blood pressure (138%) 3 h after volume expansion. This was thought to result from an increase in the total peripheral resistance (133%) associated with the recovery of cardiac output (106%). The pressor response to norepinephrine (0.5 microgram/kg) was potentiated after volume expansion. These results indicate that the handling of volume by the kidney contributed to the maintenance of an elevated level of cardiac output. However, nephrectomy did not seem to interfere with the hemodynamic switching of the causative factor for blood pressure elevation from increased cardiac output to increased total peripheral resistance. Neither was the potentiation of pressor response to norepinephrine affected. 相似文献
9.
Dr. Shigeru Sakiyama Yohko Nakamura Katsuo Tokunaga Hiroshi Takazawa Yoshinori Ohwaki Toshio Nagano 《Cell and tissue research》1989,258(2):225-231
Summary In-situ hybridization experiments have been performed using isoactin ( and )-specific riboprobes in various tissues of the rat and mouse. Distribution of the grains of actin mRNAs for both and types was similar throughout sections of the rat testis. Although both mRNAs were evenly distributed in the seminiferous tubule, extremely heavy labeling was observed in about 10% of the seminiferous tubules that could be identified as stage XII of spermatogenesis. At high magnification, grains of the mRNA were found in the cytoplasm of elongating spermatids and in the Sertoli cell cytoplasm at the adluminal side. Much higher density of the grains of mRNA was observed in the neck region of the spermatids at stage XII. Thus, the dense distribution of cytoskeletal actin mRNAs is stage-specific in the tubule during spermatogenesis in the rat. The high expression of both and actin mRNAs was also observed in the epithelial cells of the intestinal crypts. 相似文献
10.
Pro----leu change at position 102 of prion protein is the most common but not the sole mutation related to Gerstmann-Str?ussler syndrome 总被引:20,自引:0,他引:20
K Doh-ura J Tateishi H Sasaki T Kitamoto Y Sakaki 《Biochemical and biophysical research communications》1989,163(2):974-979
The host-encoded prion protein (PrP) is a component of transmissible amyloid deposited in the brains affected by Gerstmann-Str?ussler syndrome (GSS). Recently GSS in two unrelated Caucasian families has been reported to be linked to an amino acid change in PrP codon 102, proline to leucine (Leu102). However, it has not been clear whether the change is commonly found to GSS regardless of ethnic origin. We report here that Leu102 is also found in all the Japanese GSS patients tested. Interestingly, one French GSS patient was found to have another change, alanine to valine in codon 117 (Val117), instead of Leu102. Our results indicate that Leu102 is closely related to GSS irrespective of ethnic origin, but not the sole mutation related to GSS. Val117 may also be related to GSS. 相似文献