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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.
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
4.
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
5.
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
6.
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
7.
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
8.
Hypoxia-induced fibre type transformation in rat hindlimb muscles
Histochemical and electro-mechanical changes 总被引:1,自引:0,他引:1
Histochemical and electro-mechanical changes 总被引:1,自引:0,他引:1
Kazuo Itoh Toshio Moritani Koji Ishida Chiyoko Hirofuji Sadayoshi Taguchi Minoru Itoh 《European journal of applied physiology and occupational physiology》1990,60(5):331-336
Twelve male Sprague-Dawley rats (21 days old) were randomly assigned into two experimental groups: sea level control (CONT) and hypobaric hypoxia (HYPO). The HYPO rats were kept in an hypobaric chamber maintaining a simulated altitude of 4000 m (61.1 kPa). After 10 weeks of treatment, the rat hindlimb muscles [soleus (SOL) and extensor digitorum longus (EDL)] were subjected to histochemical and electro-mechanical analyses. Results indicated that compared to CONT the HYPO SOL muscle had a significantly greater relative distribution of fast-twitch-oxidative-glycolytic (FOG) fibres (28.9% SEM 2.0 vs 18.3% SEM 1.8, P less than 0.01) with a significant decrease in slow twitch oxidative fibre distribution (69.5% SEM 2.4 vs 82.9% SEM 3.1, P less than 0.01). Compared to CONT the HYPO EDL muscle also manifested a significant increase in FOG fibre distribution (51.6% SEM 0.8 vs 46.6% SEM 1.1, P less than 0.01), but this was accompanied by a significant decrease in fast twitch glucolytic fibres (44.3% SEM 0.9 vs 49.2% SEM 1.7, P less than 0.05). These histochemical fibre type transformations accompanied significant and expected changes in the electro-mechanical parameters tested in situ, e.g. maximal twitch force, maximal rate of force development, contraction time, half relaxation time, force: frequency curve, and fatigability. It was concluded that chronic hypobaric hypoxia could have a potent influence upon the phenotype expression of muscle fibres. 相似文献
9.
10.
Kojiro Kurisu Yasuyoshi Ohsaki Kengo Nagata Tetsuichiro Inai Toshio Kukita 《Cell and tissue research》1992,267(3):429-435
Summary In order to examine the intracellular distribution of precursors of type I and type III collagen and fibronectin in the palatal mesenchymal (MEPM) cells of the mouse embryo cultured under ascorbate-deficient conditions, immuno-electron-microscopic studies were carried out by use of affinity purified antibodies for these proteins. MEPM cells were obtained from the palatal shelves of 14-day-old mouse fetuses and cultured for 3–7 days in medium, either with or without 50 ng/dish/day ascorbic acid. Results obtained were as follows: (1) Although the rough endoplasmic reticulum (rER) of MEPM cells cultured for 5 days in ascorbate-supplemented medium was flattened, that in cells cultured in ascorbate-deficient medium had a distended or vesicular appearance. (2) Vesicular or distended rER showed heterogeneous staining for both type I and type III collagen, namely, some parts of rER showed positive staining for both types of collagen, while others showed negative staining. (3) Both type I and type III collagen showed codistribution in the same vesicular rER. (4) Vesicular rER showed negative or very faint labelling for fibronectin. These results may suggest regional differences in the function of rER. 相似文献