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101.
M Imamura H Fujimoto T Fukuhara M Kobayashi S Hashino M Kasai K Sakurada T Miyazaki 《Immunobiology》1988,177(1):91-103
The supernatant from cultures of T cell clones derived from (BALB/c----C3H/He) chimeras suppresses BALB/c anti-C3H/He or BALB/c anti-C57BL/6 MLRs. When we studied the alloantigen specificity of the suppressor activity in culture supernatant, we observed three types of the suppressor activity (i.e., the suppressor activity against BALB/c anti-C3H/He MLR, against BALB/c anti-C57BL/6 MLR, and against both MLRs) on day 3 after stimulation of the T cell clones with 20% crude IL2 and feeder cells. Since the alloantigen specificity fluctuated somewhat with time, we considered that a time-course study was needed to determine it correctly. We thought it unlikely that any IFN-gamma or PGE2 in the culture supernatant of the T cell clones would have mediated the suppression. Our results suggest that alloantigen specific and non-specific suppressor T cells exist in bone marrow chimeras. The former appears to play an important role in inducing and maintaining transplantation tolerance, while the latter seems to have a rather harmful effect upon chimeras. 相似文献
102.
The dopamine agonist cabergoline provides neuroprotection by activation of the glutathione system and scavenging free radicals 总被引:4,自引:0,他引:4
Yoshioka M Tanaka Ki Miyazaki I Fujita N Higashi Y Asanuma M Ogawa N 《Neuroscience research》2002,43(3):259-267
Free radicals are involved in the pathogenesis and/or progression of Parkinson's disease (PD). Several ergot derivative dopamine (DA) agonists have been reported to scavenge free radicals in vitro and to show a neuroprotective effect in vivo. We investigated the in vitro free radical scavenging and antioxidant activities of cabergoline, a long-acting ergot DA agonist, as well as its ability to activate glutathione (GSH), catalase (Cat) and superoxide dismutase (SOD) activating effects and its in vivo neuroprotective properties against 6-hydroxydopamine (6-OHDA) intracerebroventricularly (i.c.v.) in mice. The striatal DA turnover induced by i.c.v. injection of 6-OHDA was completely normalized by pretreatment with cabergoline. Moreover, cabergoline scavenged free radicals in vitro and significantly reduced lipid peroxidation in vitro and in vivo. Furthermore, daily administration of cabergoline to mice significantly increased striatal GSH levels by activation of RNA expressions of GSH-related enzymes, although striatal Cat and SOD activities did not change. In addition, our present results suggest that repeated administration of cabergoline attenuates both 6-OHDA-induced nigrostriatal DAergic dysfunction and DA neuronal cell death, since cabergoline also had a neuroprotective effect in the immunohistochemical experiment. In conclusion, our findings indicate that the multiple antioxidant mechanisms of cabergoline, such as activation of the GSH system and the direct free radical scavenging activity, may explain the neuroprotective effect of this ergot DA agonist. 相似文献
103.
Hata T; Aoki S; Manabe A; Hata K; Miyazaki K 《Human reproduction (Oxford, England)》1997,12(8):1800-1804
Our purpose was to visualize normal embryonal and fetal surface anatomical
structures in the first trimester of human pregnancy by use of
three-dimensional ultrasonography with a specially developed abdominal
three-dimensional transducer. Four embryos and 31 fetuses of 8-13 weeks
gestation were studied with a specially-developed abdominal
three-dimensional transducer (3.5 MHz). This imaging system can provide
conventional two-dimensional ultrasonography images and can also generate,
within seconds, high-quality three-dimensional images in the surface and
transparent mode with no need for an external workstation. The percentage
of surface anatomical structures visualized at each gestational age
interval using two-dimensional and three-dimensional ultrasonography is
presented. Head and trunk were depicted in all cases. The number and the
clarity of visualization of face, upper and lower extremities, hand, and
foot increased with advancing gestation. The free loop of the umbilical
cord was depicted in most cases. The number of depictions of abdominal cord
insertion, midgut herniation, and yolk sac decreased with the increase of
gestation. Genitals could not be identified in the first trimester. The
ability to view some surface anatomical structures (face, hand, and foot)
was better with three-dimensional ultrasonography than with two-dimensional
ultrasonography. Three-dimensional ultrasonography provides a novel means
for visualization of surface anatomical structures of the embryo and early
fetus. These results suggest that three-dimensional ultrasonography can
become an important modality in future embryological and early fetal
research and in detection of embryonic and fetal developmental disorders in
the first trimester of pregnancy.
相似文献
104.
105.
Characterization of T-cell tolerance to hepatitis B virus (HBV) antigen in transgenic mice. 总被引:3,自引:0,他引:3
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We made three different lines of hepatitis B virus (HBV) transgenic mice which express different amounts of hepatitis B e antigen (HBeAg) and/or hepatitis B core antigen (HBcAg) to analyse the cellular mechanisms of HBcAg specific T-cell tolerance. BS10 (official designation, 1.2HB-BS10) transgenic mice, which contain the whole HBV genome, express relatively high amounts of HBeAg in the serum and HBcAg in the liver. SPC mice, which contain hepatitis B virus core and precore gene, express small amounts of HBeAg in the serum but not HBcAg in the liver. SC33 mice, which contain only hepatitis B core gene, do not express HBeAg in the serum but express HBcAg in the liver. BS10 mice showed a very low anti-HBc antibody response after primary and secondary immunizations with recombinant HBcAg compared to transgenic host C57BL/6 (B6) mice. SPC mice showed an almost equal level of anti-HBc antibody response compared to B6 mice. SC33 mice contained anti-HBc antibody even before immunization and showed high titres of anti-HBc antibody response after immunization with HBcAg. Analysis of cellular site(s) of low responsiveness of BS10 mice revealed that proliferating and helper T cells are specifically tolerant to HBcAg. B cells and antigen-presenting cells in BS10 mice were not defective. SC33, SPC and BS10 mice differ a little in their developmental expression of HBc/HBeAg. Our results suggest critical roles of the nature (circulating versus non-circulating) as well as the time of expression of self-antigens in T-cell tolerance. 相似文献
106.
Taisuke Nakao 《Anatomical record (Hoboken, N.J. : 2007)》1975,182(3):321-337
The myotendinous junction in the skeletal muscle of adult lamprey Lampetra japonica was studied with an electron microscope. Numerous finger-like sarcolemmal invaginations were present at the ends of muscle fibers to form the myotendinous junction. Parietal fibers of each muscle unit showed more closely distributed sarcolemmal invaginations than central fibers. Features of the myotendinous junction. Parietal fibers of each muscle unit showed more closely distributed sarcolemmal invaginations than central fibers. Features of the myotendinous junction generally conform to the accounts in the literature. The sarcolemmal invagination was covered on its sarcoplasmic aspect by the connecting filament layer and the dense amorphous attachment layer, and on the extracellular aspect by the intermediary layer and the external lamina with collagen fibrils arising from the myosepta. Sarcolemmal invaginations were sometimes seen to consist of a pair of sarcolemmas of adjacent muscle fibers within a muscle unit, which is characteristic to the myotendinous junction of lamprey. It is noteworthy that the connecting filament layer is much thinner than that, e.g., in the tadpole tail muscles (Nakao, '74). Furthermore, it is much thicker in the parietal fibers than in the central fibers. The sarcolemma of the terminal segment of the invagination frequently showed specific coupling with cisterns of the sarcoplasmic reticulum (terminal coupling). The external lamina is partially or completely deficient in the terminal segment of sarcolemmal invaginations which form terminal couplings so that collagen fibrils contained in the invagination appear to be in direct contact with the sarcolemma; however, definite relationships of collagen fibrils with the sarcolemma and the external lamina in the terminal segment of invagination still remain obscure. This type of coupling is considered to play a role in the coupling of excitation to contraction of muscle fibers as triads and diads. 相似文献
107.
Katsutoshi Kawasaki Shigeru Miyazaki Eishin Yaoita Takashi Kazama Tadashi Yamamoto Itaru Kihara 《Pathology international》1986,36(3):429-437
A clearance kinetic study of intravenously administered 125 I-labeled aggregated human IgG (125 I-AHIgG) from the circulation and its distribution in various organs was performed weekly during the course in a model of experimental immune complex glomerulonephritis which was induced in rats immunized 8 weeks previously with 6 times a week administration of 2 mg of bovine serum albumin (BSA) for 4 weeks from week 8 to 12. The removal rates of the injected 125 I-AHIgG from the circulation were retarded in nonproteinuric rats of week 9 and 10, at almost every checked point (p-value was <0.01). The clearance in those rats with severe proteinuria returned to the level of the control and of rats in week 8. The distribution of 125 I-AHIgG in the liver 4 hours after the administration revealed a considerable decrease in non-overt proteinuric rats of weeks 9, 10, and 11. A similar tendency of decreasing depositions of the radioactivity was shown in the spleen at each 4 hours. In contrast, the uptakes in the kidney and lung at the final week of 12 were larger. Delayed clearance from the circulation and a decreasing handle of the injected macromolecule in the liver and possibly in the spleen may suggest the presence of some impairment of the MPS function in the course of this experimental glomerulonephritis. 相似文献
108.
Although there have been reported associations between zinc and bone mineral density (BMD), no reports exist on the effect of zinc treatment in osteoporotic patients. Therefore, we investigated the efficacy and safety of zinc pharmacotherapy in Japanese elderly patients. The present investigation included 122 osteoporotic patients with zinc deficiency, aged ≥65 years, who completed 12 months of follow-up. In addition to standard therapy for osteoporosis in a clinical setting, the subjects received oral administration of 25 mg zinc (NOBELZIN®, an only approved drug for zinc deficiency in Japan) twice a day. BMD and laboratory data including bone turnover markers were collected at 0 (baseline), 6, and 12 months of zinc treatment. Neither serious adverse effects nor incident fractures were seen during the observation period. Serum zinc levels were successfully elevated by zinc administration. BMD increased significantly from baseline at 6 and 12 months of zinc treatment. Percentage changes of serum zinc showed significantly positive associations with those of BMD. Bone formation markers rose markedly from the baseline values, whereas bone resorption markers displayed moderate or no characteristic changes. Additive zinc supplementation may contribute to BMD augmentation ensuing the prevention of fracture occurrence in elderly osteoporotic patients with zinc deficiency. 相似文献
109.
110.
Shigemi K Takahashi H Hashimoto S Nomi S Chihara E Kinoshita T Tanaka Y Miyazaki M 《Journal of anesthesia》1990,4(1):91-93
Finger arterial blood pressures determined by a newly developed sphygmomanometer, HEM-802F, were compared with arterial pressure obtained from direct measurement of the radial artery. An excellent correlation was found between the two methods (systolic: r = 0.93, diastolic: r = 0.91), although there was a large variability among individual subjects. The range of differences between them are from +32 to –13mmHg for systolic and +15 to –25mmHg for diastolic blood pressure measurement. HEM-802F underestimated systolic pressure (–4.0mmHg) and overestimated diastolic pressure (+6.7mmHg), compared with intra-arterial readings.The HEM-802F was useful for the non-invasive arterial pressure monitoring during general anesthesia.(Shigemi K, Takahashi H, Hashimoto S et al.: A comparative study of measurement of arterial blood pressure using HEM-802F and arterial cannulation. J Anesth 4: 91–93, 1990) 相似文献