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71.
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73.
A new reaction for glycine biosynthesis 总被引:3,自引:0,他引:3
74.
K Hayashi T Kodaira K Baba K Kikuchi 《Nihon saikingaku zasshi. Japanese journal of bacteriology》1966,21(10):633-639
75.
G Kikuchi 《Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme》1965,10(14):1458-1466
76.
Hershenson M. B.; Kikuchi Y.; Tzelepis G. E.; McCool F. D. 《Journal of applied physiology》1989,66(2):750-754
Because the inspiratory rib cage muscles are recruited during inspiratory resistive loaded breathing, we hypothesized that such loading would preferentially fatigue the rib cage muscles. We measured the pressure developed by the inspiratory rib cage muscles during maximal static inspiratory maneuvers (Pinsp) and the pressure developed by the diaphragm during maximal static open-glottis expulsive maneuvers (Pdimax) in four human subjects, both before and after fatigue induced by an inspiratory resistive loaded breathing task. Tasks consisted of maintaining a target esophageal pressure, breathing frequency, and duty cycle for 3-5 min, after which the subjects maintained the highest esophageal pressure possible for an additional 5 min. After loading, Pinsp decreased in all subjects [control, -128 +/- 14 (SD) cmH2O; with fatigue, -102 +/- 18 cmH2O; P less than 0.001, paired t test]. Pdimax was unchanged (control, -192 +/- 23 cmH2O; fatigue, -195 +/- 27 cmH2O). These data suggest that 1) inability to sustain the target during loading resulted from fatigue of the inspiratory rib cage muscles, not diaphragm, and 2) simultaneous measurement of Pinsp and Pdimax may be useful in partitioning muscle fatigue into rib cage and diaphragmatic components. 相似文献
77.
78.
Role of carbohydrate moiety of IL-5. Effect of tunicamycin on the glycosylation of IL-5 and the biologic activity of deglycosylated IL-5 总被引:4,自引:0,他引:4
A Tominaga T Takahashi Y Kikuchi S Mita S Naomi N Harada N Yamaguchi K Takatsu 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(4):1345-1352
IL-5 is a T cell-derived lymphokine that induces B cell growth and differentiation in murine systems. In this study, we examined the role of carbohydrate moiety of IL-5 in the expression of biological function. IL-5 polypeptides translated in Xenopus oocytes were heterogeneous in terms of isoelectric point (pI 4.7 to 8.0) and m.w. (45,000 to 60,000 under nonreducing conditions) and yielded m.w. of 25,000 to 30,000 under reducing conditions. Treatment of rIL-5 with N-glycanase under reducing conditions yielded an IL-5 monomer of m.w. 12,000 to 14,000. Furthermore, deglycosylated rIL-5 that had been translated in the presence of tunicamycin showed very limited heterogeneity by two-dimensional gel electrophoresis (first dimension, nonequilibrium pH gradient electrophoresis; second dimension, SDS-PAGE). The m.w. was 27,000 to 28,000 under non-reducing conditions and migrated to m.w. 13,000 to 14,000 under reducing conditions. These results indicate that IL-5 is a glycoprotein carrying the N-glycosidically-linked carbohydrates. Treatment of IL-5 with sialidase caused the decrease in the heterogeneity in isoelectric point of IL-5. Deglycosylated rIL-5 that had been obtained from tunicamycin-treated oocytes could bind to IL-5-responding cells (T88-M), which express both high- and low-affinity IL-5 receptors, as efficient as intact rIL-5 under high-affinity conditions. Scatchard plot analysis of equilibrium binding of 35S-labeled rIL-5 to T88-M cells revealed that the dissociation constants (Kd) of glycosylated rIL-5 and deglycosylated rIL-5 were 127 pM and 110 pM, respectively. IL-5 activities determined by both B cell growth and differentiation assays were not affected by deglycosylation. These results indicate that N-linked glycoside moiety of IL-5 molecules may not play an essential role in the expression of its activity. 相似文献
79.
Mikio Yoshidomi Takashi Hayashi Koji Abe Kyuya Kogure 《Journal of neurochemistry》1989,53(5):1589-1594
The effects of a new calcium channel blocker, 1-[bis(4-fluorophenyl)methyl]-4-(2,3,4-trimethoxybenzyl)-piperazine dihydrochloride (KB-2796), on delayed neuronal death (DND) in the hippocampus were examined in gerbils in comparison with those of pentobarbital and flunarizine. The neuronal density in the hippocampal CA1 subfield was counted on the seventh day of recirculation following 5 min of bilateral carotid occlusion, and protein biosynthesis in the brain was also determined at 1, 2, 4, 24, and 72 h following occlusion. The drugs were intraperitoneally administered after recirculation. KB-2796 (10 mg/kg) significantly prevented DND in the CA1 subfield. Pentobarbital (40 mg/kg), but not flunarizine (3 and 10 mg/kg), inhibited DND. Protein synthetic activity in the CA1 subfield was reduced by ischemia and the reduction was not restored even at 72 h after recirculation. KB-2796 did not ameliorate the reduction of protein synthesis in the CA1 subfield by 24 h after recirculation, but in one of three animals restoration of protein synthesis was observed at 72 h of recirculation. Pentobarbital also restored the reduced protein synthesis in two of three animals at 72 h. These results suggest that calcium influx into neurons participates in the pathogenesis of DND, and also that KB-2796 might prevent both morphological and functional cell damage in CA1 neurons induced by transient ischemia. 相似文献
80.
A Kikuchi T Sasaki S Araki Y Hata Y Takai 《The Journal of biological chemistry》1989,264(16):9133-9136
The smg-21 GTP-binding protein (smg p21) has the same effector domain as the ras proteins (ras p21s) and is identical with the proteins of the rap1A and Krev-1 genes. In this paper, two proteins stimulating the GTPase activity of smg p21 are partially purified from bovine brain cytosol. These proteins, designated as smg p21 GTPase-activating protein (GAP) 1 and 2, are separated from a c-ras p21 GAP described previously by column chromatographies. smg p21 GAP1 and -2 stimulate the GTPase activity of only smg p21 but not that of c-Ha-ras p21 or the rho and smg-25A GTP-binding proteins. smg p21 GAP1 or -2 does not stimulate the dissociation of guanosine 5'-3-O-(thio)triphosphate or GDP from smg p21. smg p21 GAP1 or -2 themselves do not have GTP/GDP binding or GTPase activity. The Mr values of smg p21 GAP1 and -2 are estimated to be 250-400 x 10(3) and 80-100 x 10(3) by gel filtration and sucrose density gradient ultracentrifugation, respectively. The activity of smg p21 GAP1 and -2 is killed by tryptic digestion or heat boiling. These results indicate that bovine brain contains two smg p21 GAPs in addition to c-ras p21 GAP. 相似文献