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91.
Heritability of C-Reactive Protein and Association with Apolipoprotein E Genotypes in Japanese Americans 总被引:1,自引:0,他引:1
M. A. Austin C. Zhang S. E. Humphries W. L. Chandler P. J. Talmud K. L. Edwards D. L. Leonetti M. J. Mcneely W. Y. Fujimoto 《Annals of human genetics》2004,68(3):179-188
Numerous studies have demonstrated that increased C‐reactive protein (CRP) levels predict coronary heart disease, stroke, peripheral vascular disease, and diabetes, and are associated with features of the metabolic syndrome. Only three previous studies have investigated the heritability of CRP levels, primarily in samples of Caucasian families.The purpose of the present study was to estimate the magnitude of genetic influences on CRP levels, and to examine potential associations between variation in the APOE gene and CRP levels, using a sample of 562 individual Japanese Americans from 68 extended kindreds. In general, correlation coefficients between first‐degree relatives for CRP were approximately 0.2, and spouse correlations did not differ from zero, consistent with genetic influences. Heritability estimates were approximately 0.3 (p < 0.01), even with adjustment for factors known to influence CRP levels. A significant relationship was seen between unadjusted CRP levels and APOE genotypes (p = 0.02), with the highest mean CRP level among ?2 carriers (1.20 mg/L), and nearly the same mean levels among ?3/?3 subjects and ?4 carriers (0.72 and 0.74 mg/L, respectively). However, this relationship was diminished with adjustment for covariates (p = 0.07). These results demonstrate the presence of both genetic and environmental effects on CRP levels among Asian Americans, and additional studies are needed to determine if the APOE gene contributes to these genetic influences. 相似文献
92.
Modulation of neuronal histamine in control of food intake 总被引:4,自引:0,他引:4
T Sakata K Fukagawa K Ookuma K Fujimoto H Yoshimatsu A Yamatodani H Wada 《Physiology & behavior》1988,44(4-5):539-543
Neuronal histamine affects physiological functions of the hypothalamus. To investigate involvement of histamine receptors in feeding, histamine antagonists were infused into the rat third cerebroventricle. All H1- but no H2-antagonists tested, induced transient feeding during the early light when concentration of hypothalamic histamine was highest. No periprandial drinking was observed. Ambulation concomitantly increased during feeding. The effect on feeding was attenuated when brain histamine was normally low during the early dark or was decreased by alpha-fluoromethylhistidine (alpha-FMH). Bilateral microinjection indicated that the ventromedial hypothalamus, but not the lateral hypothalamus or the paraventricular nucleus, was a main locus for the induction of feeding by an H1-antagonist. The effect was completely abolished when brain histamine was decreased by pretreatment with alpha-FMH. Hypothalamic neuronal histamine suppresses food intake, at least in part, through H1-receptors in the VMH, and diurnal fluctuations of food intake may mirror neuronal histamine level. 相似文献
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96.
Coexpression of growth arrest-specific gene 6 and receptor tyrosine kinases,Axl and Sky,in human uterine endometrium and ovarian endometriosis 总被引:4,自引:0,他引:4
We demonstrated the expression of Gas6, the protein product of the growth arrest-specific gene 6 (gas6) and a member of the vitamin K-dependent protein family, and its receptor tyrosine kinases, Axl and Sky, in human uterine and ovarian endometriotic endometria using RT-PCR-Southern blot analysis and immunohistochemistry. Gas6, Axl and Sky mRNA were detected in all samples analysed. There was no significant difference between the levels of Sky mRNA in normal uterine and endometriotic endometria; however, the levels of Gas6 and Axl mRNA in endometriotic endometria were significantly higher than in normal endometria. These mRNA levels showed no significant alteration during the menstrual cycle. In the immunohistochemical study, Gas6, Axl and Sky were found in endometrial glandular cells and stromal cells in all samples analysed. This study demonstrates the coexpression of receptor tyrosine kinases and their ligand, Gas6, in normal uterine and ovarian endometriotic endometria, and the overexpression of Axl and Gas6 in endometriotic endometria. It is suggested that Gas6 and Axl signal transduction is aberrantly stimulated in endometriotic endometria, and is plausibly related to its growth potential. 相似文献
97.
High NK cell activity in early pregnancy correlates with subsequent abortion with normal chromosomes in women with recurrent abortion 总被引:12,自引:0,他引:12
Yamada H Kato EH Kobashi G Ebina Y Shimada S Morikawa M Sakuragi N Fujimoto S 《American journal of reproductive immunology (New York, N.Y. : 1989)》2001,46(2):132-136
PROBLEM: The aim of this study was to assess the role of natural killer (NK) cells in pregnant women with a history of recurrent spontaneous abortion (RSA). METHOD OF STUDY: Consecutive 66 pregnant women with a history of RSA were prospectively assessed for peripheral NK cell activity, percentage of the NK cell subsets, and subsequent pregnancy outcome. RESULTS: NK cell activity in women with subsequent live birth (group I) at 4-5 gestational weeks (GW) (mean +/- SD, 32.5 +/- 12.31%) significantly decreased at 6-7 GW (28.1 +/- 12.1%) and at 8 9 GW (28.0 +/- 11.8%). NK cell activity in women with subsequent abortion with normal chromosomes (group II) at 6 7 GW (41.2 +/- 19.0%) was significantly higher than that in group I women, while NK cell activity at 6-7 GW in women with subsequent abortion with abnormal chromosomes (group III) was the same as the level in group I women. CONCLUSIONS: High NK cell activity at 6-7 GW correlates with subsequent abortion with normal chromosomes. 相似文献
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99.
Hiroshi Ueda Yoshiaki Doi Yoshitaka Sakamoto Kunshige Hamasaki Sunao Fujimoto 《Anatomical record (Hoboken, N.J. : 2007)》1992,232(2):257-261
Simultaneous immunoelectron microscopic localization of histamine and factor VII-related antigen was examined on the same ultrathin section of the endothelium of the human umbilical vein from full-term deliveries by means of the double-immunolabeling technique. Small gold particles demonstrating antibody reaction with histamine are preferentially located in the cytoplasmic matrix and organelles, especially in mitochondria and on the luminal membrane surface of the endothelial cells. The gold particles representing histamine immunoreactivity also located on some of Weibel Palade (WP) bodies. In contrast, large gold particles demonstrating factor VII-related antigen are concentrated preferentially on most WP bodies. Single labeling of either histamine or factor VIII-related antigen shows similar results to those of the double labeling. The present study indicates that some WP bodies are involved in storage of both factor VIII-related antigen and histamine, but others store factor VIII-related antigen only. This difference in contents of WP bodies may be induced during the development and maturation process of this inclusion. At any rate, it is reasonable to consider that WP bodies have important roles in both vascular tonus and hemostasis during the vascular obliteration. 相似文献
100.
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