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1.
Kei Kamide Yoshihiro Kokubo Hironori Hanada Junko Nagura Jin Yang Shin Takiuchi Chihiro Tanaka Mariko Banno Yoshikazu Miwa Masayoshi Yoshii Tetsutaro Matayoshi Hisayo Yasuda Takeshi Horio Akira Okayama Hitonobu Tomoike Yuhei Kawano Toshiyuki Miyata 《Hypertension research》2006,29(4):243-252
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese. 相似文献
2.
Hironobu Ishiyama Makoto Sato Kuniko Matsumura Miwa Sento Keiki Ogino Tatsuya Hobara 《Basic & clinical pharmacology & toxicology》1995,77(4):293-298
Abstract: Intravenous injection of gadolinium chloride (GdCl3) at a dose of 10 mg/kg caused an increase in proliferating cell nuclear antigen labeling index and the grade of pyronin positivity (RNA level) in rat liver. In CCl4-exposed rats, pretreatment with GdCl3 also showed a preventive effect of the liver injury both biochemically and histologically. Moreover, the proliferative action preceded the attenuative effect of the liver injury. Results suggest that GdCl3 induces hepatocyte proliferation, and this action of GdCl3 may modify the development of CCl4-induced liver injury. 相似文献
3.
Nitrosation of amines by stimulated macrophages 总被引:10,自引:2,他引:8
Rats and mice treated in vivo with Escherichia coli lipopolysaccharide (LPS) synthesize and excrete large quantities of nitrate. Murine peritoneal macrophages, elicited in vivo with thioglycolate and stimulated in vitro with LPS and/or gamma-interferon (IFN), produce copious amounts of nitrate and nitrite. We report here experiments showing N-nitrosamine formation by macrophages immunostimulated in vitro. Macrophage cell lines J774.1, PU5-1.8, WEHI-3 and RAW 264 and freshly isolated macrophages from C3H/He mice were used. Macrophages were cultured in Dulbecco's modified Eagle's medium (pH 7.5) supplemented with calf serum (10%). Supernatant NO2- and NO3- were measured. N-Nitrosamines were extracted with dichloromethane and the extracts analyzed by a gas chromatography--thermal energy analyzer. Cells (1.5 X 10(6)/ml) were incubated with LPS (10 micrograms/ml) and morpholine (15 mM) for 72 h at 37 degrees C. Under these conditions, all of the cell types listed above produced nitrite (40-70 microM) and N-nitrosomorpholine (NMOR; 114-940 nM). LPS was required for both processes, and this effect was enhanced by IFN. Nitrite (150 microM) incubated with morpholine in cell-free medium did not form NMOR nor did cells plus morpholine and NO2-. The rate of NMOR formation in the J774.1 cell line was highest in the middle incubation period (24-36 h) although [NO2-] was highest in the final incubation period (48-72 h). Thus, the cells do not catalyze nitrosamine formation per se, rather the amine traps out a reactive nitrosating species prior to the formation of NO2- and NO3-. These results suggest that immunostimulated macrophages may be capable of nitrosamine formation under physiological conditions. 相似文献
4.
5.
K Satomi Y Kinoshita S Hirakawa 《Cortex; a journal devoted to the study of the nervous system and behavior》1991,27(2):327-331
If defective cross-localization of fingertips (CLF) in callosal patients is due to a deficit in the interhemispheric transfer of somesthetic information, when the patient's eyes are open, CLF should be affected when the stimulated hand is excluded from vision, not when the responding hand is excluded from vision. In order to investigate this hypothesis, a patient with a callosal lesion was subjected to CLF with eyes closed and open. With eyes closed, the CLF score in the left-to-right direction was significantly lower than that in the right-to-left direction. With eyes open, the CLF performance in the right-to-left direction was impaired when it was the responding hand to be excluded from vision, not when it was the stimulated hand to be excluded from vision. It would, therefore, appear that the patient's CLF disturbance was not due to a somesthetic transfer deficit, but to left unilateral apraxia for the right-to-left direction errors and to left tactile finger anomia for the left-to-right direction errors. 相似文献
6.
The precise course and termination levels of the corticospinal tract (CST) in the cat were studied using the anterograde transport of wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP). Following injection of WGA-HRP into the pericruciate (sensorimotor) cortex on one side, we observed the precise caudal termination levels of the CST fibers in the lateral and ventral funiculi. Simultaneously, the bilateral CSTs descending through the dorsal funiculus of the spinal cord were identified. Anterogradely labeled CST fibers within the lateral and ventral funiculi were observed bilaterally to reach the level of the third sacral (S3) spinal segment, which is lower than that ever described. The lowest level of the CST fibers within the dorsal funiculus, however, reached the level of the first sacral (S1) spinal segment. In conclusion, this study demonstrates that, in the cat, there exist 6 different CSTs (crossed and uncrossed lateral, ventral, dorsal) and that the termination levels of the lateral and ventral CSTs are much lower than those described in previous reports. 相似文献
7.
8.
In fetal rats whose dams were fed a low-protein diet, 35S sulfate uptake into the growth plate of the long bone and rib was higher than in the control group. The elution pattern of guanidine-HCl extract in gel chromatography revealed that the malnourished group had more high molecular weight proteoglycans in the dissociative condition and a larger aggregated portion in the associative condition than did the control group; however, the same chondroitin-sulfate chain size existed. Calcium content did not differ in both groups. Aggregated proteoglycan or a high molecular weight proteoglycan that existed in the malnourished group probably played an inhibitory role in calcification. Prenatal protein-energy malnutrition may delay the change of proteoglycan character, which could affect mineralization of fetal bones. 相似文献
9.
Satomi Kitagawa Yu Yamaguchi Emiko Sameshima Masaru Kunitomo 《Clinical and experimental pharmacology & physiology》1994,21(12):963-970
1. Endothelium-dependent relaxation in response to acetylcholine (ACh) and the calcium ionophore A 23187 was examined in aorta, coronary, basilar and renal arteries isolated from Watanabe heritable hyperlipidaemic (WHHL) rabbits of 2, 6 and 12 months of age, with normolipidaemic heterozygous WHHL rabbits as controls. 2. In the rings of WHHL rabbit aortae and coronary arteries preconstricted with vasoconstrictors, endothelium-dependent relaxation in response to ACh was attenuated with age compared to the heterozygous WHHL rabbits. A significant negative correlation was found between the total cholesterol content and the relaxation response to ACh in the aortae or coronary arteries from 6 and 12 month old WHHL rabbits. 3. In the rings of basilar arteries, endothelium-dependent relaxations to ACh were not modified with age. Similarly, in the rings of renal arteries, the relaxation response to ACh was not changed with age, but in the 6 and 12 month preparations, after the age of 6 months, a contraction following the relaxation appeared at higher concentrations of ACh (10?7 to 10?6 mol/L). The contraction was endothelium-dependent and inhibited by indomethacin. 4. A 23187-induced endothelium-dependent relaxations were also markedly attenuated in the aorta and significantly in the coronary artery with age. 5. Endothelium-independent relaxation to sodium nitroprusside was not changed in all arteries from WHHL rabbits of different ages. 6. These findings indicate that in the aorta and coronary artery of the WHHL rabbit, the endothelium-dependent relaxation to ACh and A 23187 becomes impaired with increasing age (i.e., with the progression of cholesterol deposition in the arterial wall) but is preserved in the basilar and renal artery. 相似文献
10.
Hiroki Sato Atsushi Watanabe Tamotsu Yamaguchi Nobuhiro Harada Akihiko Yamauchi Satomi Inoue Tomio Abe 《Annals of thoracic and cardiovascular surgery》2005,11(1):41-43
Intralobar pulmonary sequestration associated with asymptomatic aspergillosis is a rare case. We describe the case of a 65-year-old woman with intrapulmonary sequestration, anomalous systemic arterial supply to the left lower lobe and aspergillosis who underwent left lower lobectomy and ligation of an anomalous artery by Video-Assisted Thoracoscopic surgery (VATS). Pathological examination showed the parenchymal distortion and chronic inflammation. Aspergillus were found in the cyst. VATS lobectomy for intralobar pulmonary sequestration is a safe and valid procedure. 相似文献