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991.
992.
Y. Hotta Keiko Fujiki Mutsuko Hayakawa Takashi Ohta Takuro Fujimaki Kouichi Tamaki Toshiyuki Yokoyama Atsushi Kanai Akito Hirakata Tetsuo Hida Sachiko Nishina Noriyuki Azuma 《Human genetics》1998,103(2):142-144
We investigated the XLRS1 gene in Japanese patients with retinoschisis (RS). All exons of the XLRS1 gene were sequenced in 14 males, including a pair of monozygotic twins, from 11 individual families with RS and five of their
mothers who are asymptomatic but diagnosed as carriers. Six kinds of missense mutations and a nonsense mutation, including
six novel mutations, were detected in all 14 patients and carriers. Mutations in the XLRS1 gene are also responsible for RS in non-Caucasian patients. Most Japanese RS cases are caused by an XLRS1 gene defect. A novel mutation, Glu72Lys, was found in four families, suggesting a common mutation in the Japanese population.
Clinical features of RS patients with both the Glu72Lys and Pro193Leu mutations indicate that a genotype–phenotype correlation
is not recognized in RS.
Received: 12 January 1998 / Accepted: 21 March 1998 相似文献
993.
Keiko Tanaka Izumi Shibuya Yasuhito Uezono Yoichi Ueta Yumiko Toyohira Nobuyuki Yanagihara Futoshi Izumi †Tomio Kanno Hiroshi Yamashita 《Journal of neurochemistry》1998,70(4):1652-1661
Abstract: Pituitary adenylate cyclase-activating polypeptide (PACAP) causes both Ca2+ release and Ca2+ influx in bovine adrenal chromaffin cells. To elucidate the mechanisms of PACAP-induced Ca2+ release, we investigated expression of PACAP receptors and measured inositol trisphosphates (IP3), cyclic AMP, and the intracellular Ca2+ concentration in bovine adrenal medullary cells maintained in primary culture. RT-PCR analysis revealed that bovine adrenal medullary cells express the PACAP receptor hop, which is known to couple with both IP3 and cyclic AMP pathways. The two naturally occurring forms of PACAP, PACAP38 and PACAP27, both increased cyclic AMP and IP3, and PACAP38 was more potent than PACAP27 in both effects. Despite the effects of PACAP on IP3 production, the Ca2+ release induced by PACAP38 or by PACAP27 was unaffected by cinnarizine, a blocker of IP3 channels. The potencies of the peptides to cause Ca2+ release in the presence of cinnarizine were similar. The Ca2+ release induced by PACAP38 or by PACAP27 was strongly inhibited by ryanodine and caffeine. In the presence of ryanodine and caffeine, PACAP38 was more potent than PACAP27. PACAP-induced Ca2+ release was unaffected by Rp-adenosine 3′,5′-cyclic monophosphothioate, an inhibitor of protein kinase A. Ca2+ release induced by bradykinin and angiotensin II was also inhibited by ryanodine and caffeine, but unaffected by cinnarizine. Although IP3 production stimulated by PACAP38 or bradykinin was abolished by the phospholipase C inhibitor, U-73122, Ca2+ release in response to the peptides was unaffected by U-73122. These results suggest that PACAP induces Ca2+ release from ryanodine/caffeine stores through a novel intracellular mechanism independent of both IP3 and cyclic AMP and that the mechanism may be the common pathway through which peptides release Ca2+ in adrenal chromaffin cells. 相似文献
994.
The photosynthetic rate measured at 20°C was higher in ricegrown under 20/18°C day/night temperature and 350 µmoIquanta m2s1 than in rice grown under 25/20°Cand 1,000 µmol quanta m2s1, whereas therewas no difference in the photosynthetic rate measured at 25°Cbetween rice grown in these two ways. This difference was suggestedto be caused by an enhanced ribulose-l,5-bis-phosphate-regenerationcapacity in the low-temperature/ir-radiance-grown rice. (Received July 14, 1998; Accepted September 25, 1998) 相似文献
995.
Cardiovascular and humoral responses to sustained muscle metaboreflex activation in humans 总被引:4,自引:0,他引:4
Nishiyasu Takeshi; Tan Nobusuke; Morimoto Keiko; Sone Ryoko; Murakami Naotoshi 《Journal of applied physiology》1998,84(1):116-122
Nishiyasu, Takeshi, Nobusuke Tan, Keiko Morimoto, RyokoSone, and Naotoshi Murakami. Cardiovascular and humoral responses to sustained muscle metaboreflex activation in humans.J. Appl. Physiol. 84(1): 116-122, 1998.The cardiovascular and humoral responses to sustained musclemetaboreflex activation were examined in eight male volunteers whilethey performed two 24-min exercise protocols. Each of these consistedof six 1-min bouts of isometric handgrip exercise (the left and righthands being used alternately) at 50% of maximal voluntary contraction;after each bout, there was either 3-min postexercise occlusion(occlusion protocol) or 3-min rest (control protocol). In the occlusionprotocol, mean arterial blood pressure was ~25 mmHg higher thanduring the control protocol, indicating that the muscle metaboreflexwas activated during occlusion. During the control protocol, plasmarenin activity, plasma vasopressin, and adrenocorticotropic hormonevalues were not significantly different from the values at rest. Duringthe occlusion protocol, however, plasma renin activity, plasmavasopressin, and adrenocorticotropic hormone were all significantlyincreased at 25 min. These data demonstrate that, in humans, thesustained activation of the muscle metaboreflex causes the secretion of several hormones originating from different regions. 相似文献
996.
Shinsuke Umeda Radha Ayyagari Michihiro T Suzuki Fumiko Ono Fumino Iwata Keiko Fujiki Atsushi Kanai Yuichiro Takada Yasuhiro Yoshikawa Yasuhiko Tanaka Takeshi Iwata 《Experimental Animals》2003,52(2):129-135
ELOVL4, elongation factor of very long chain fatty acids-4, is known to be responsible for autosomal dominant macular degeneration and Stargardt-like macular degeneration. In this study, we cloned the monkey homologue of ELOVL4 and determined the cellular and tissue distribution of the gene product. Sequence analysis of the monkey ELOVL4 gene revealed a high degree of homology between human and monkey. The cloned full-length cDNA of monkey ELOVL4 encoded 314 amino acids, the same length as human and two amino acids longer than mouse. The monkey ELOVL4 conserved the characteristics typical of the super family of ELO enzymes involved in the metabolism of membrane-bound fatty acid elongation. Real-time quantitative PCR demonstrated that the monkey ELOVL4 gene was highly expressed in restricted tissue-specific fashion, not only in the retina but also in the skin (90% of retina) and thymus (111% of retina). Immunohistochemical analysis detected signals predominantly in the photoreceptor layer of the monkey retina. 相似文献
997.
Keiko Horiuchi Atsushi Takatori Toshiaki Inenaga Etsuko Ohta Jun Yamanouchi Seiji Kawamura Yoshiyuki Ishii Shigeru Kyuwa Yasuhiro Yoshikawa 《Experimental Animals》2002,51(5):457-464
We investigated the effect of probucol (PB) on atherosclerosis in streptozotocin (SZ)-induced diabetic-hyperlipidemic APA hamsters in three different stages, the early, middle and late stages of atherosclerosis. Male APA hamsters were injected intraperitoneally with SZ or vehicle alone (citrate buffer; CB) as a control at the age of 8 weeks. At 6 weeks after injection (WAI) of SZ or CB (the early stage), 14 WAI (the middle stage) and 26 WAI (the late stage), animals were assigned to PB treated- or non-treated groups (CBPB, SZPB, CB, SZ). After 8 weeks of PB administration with diet, the aorta was taken from each animal for assessment of atheromatous lesions and blood samples were subjected to serum biochemical analysis and the measurement of blood lipid peroxide (LPO). In the middle stage, PB treatment significantly decreased serum total cholesterol level, slightly decreased LPO, and also tended to reduce the lesion area, although no statistical difference was seen. There was no marked effect of PB treatment in the early and late stages. These findings suggest that single use of PB has little effect on atherosclerosis of a hyperglycemia-hyperlipidemia animal model. 相似文献
998.
Unno Keiko; Ando Ichiro; Hagima Naoko; Yokogaki Shuichi; Koike Chieko; Okada Shoji 《Plant & cell physiology》1992,33(7):963-969
The effects of deuterium (D) on Chlorella ellipsoidea C-27 wereinvestigated. Cells grown in a medium prepared with deuteriumoxide (D2O) showed pronounced delays in cell growth and division;the length of a cell cycle in medium with 100 mol% D2O was morethan 5 times longer than that in medium prepared in H2O Thedelay caused by D2O was not overcome by either indoleaceticacid or kinetin. The biological and ultrastractural characteristicsof deuterated .Chlorella (D-Chlorella) cells were examined.The responses of D-Chlorella to cell wall-digesting enzymesdid not differ from those of normal (H-Chlorella) cells. D-Chlorellacells were enlarged, and cellular components, such as proteins,nucleic acids, lipids and ATP, were present in larger quantitiesthan those in H-cells. The chloroplast of D-Chlorella was enlarged,but the levels of component photosynthetic pigments were significantlyreduced. By contrast, mitochondria of D-Chlorella were smallerthan those of H-cells. These changes in levels of cellular componentsand in the sizes of organelles seem to be unique to deuteration. (Received May 13, 1992; Accepted July 28, 1992) 相似文献
999.
Immune response to liver-specific lipoprotein (LSP) is involved in the pathogenesis of chronic active hepatitis. Experimental
hepatitis could thus be prepared in C57BL/6 mice by injection of liver-specific protein in a syngeneic liver homogenate with
Freund's complete adjuvant. In hepatitic mice treated with maitake (Grifola frondosa) fruit bodies, the values of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) values increased
temporarily by 2.24–2.79 times and decreased rapidly thereafter. However, in the mice given normal feed, both values increased
constantly. Thus, we examined T cell activities both in the exacerbation and remission stages of hepatitis. We suggest that
the activation of CD8+ cells is more potentiated than that of CD4+ cells by administration of maitake or the D-Fraction-glucan (β-1,6 glucan having β-1,3 branches), which can enhance immuno-competent
cells at the exacerbation stage. However, at the remission stage, marked potentiation of CD8+ cell activity was not observed. These results suggest that depressed suppressor T cell activity is revived by the X-Fraction-glucan
(β-1,6 glucan having α-1,4 branched glucan), while the cytotoxic T cell activity, which is activated by the D-Fraction, is
restricted, thereby creating a smooth shift from the exacerbation stage to the remission stage. 相似文献
1000.
Aluminum ion inhibited yeast glycerol kinase competitively with respect to the substrate MgATP. The K value of the enzyme for aluminum ion was about 3 M. Spermine at physiological concentrations prevented glycerol kinase from the inhibition by aluminum ion. Nuclear magnetic resonance spectroscopy showed the specific elimination by spermine of aluminum from the metal-ATP complex, but no dissociation of MgATP complex by spermine. Inhibition by aluminum ion of glycerol kinase as well as hexokinase can reduce the utilization of energy fuel in yeast. Change in polyamine concentration may control energy production in vivo, and is responsible for the development of age-related aluminum toxicity. © Rapid Science 1998. 相似文献