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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
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Toshio Imaizumi MD PhD Toshimi Honma MD PhD Yoshifumi Horita MD Ikuhide Kohama MD PhD Kei Miyata MD Maiko Kawamura MD Jun Niwa MD PhD 《Journal of neuroimaging》2006,16(3):236-242
BACKGROUND AND PURPOSE: Dot-like low intensity spots (dot-like hemosiderin spots: dotHSs) on gradient echo T2*-weighted MRI have been histologically diagnosed to represent old cerebral microbleeds associated with microangiopathies. They have also been correlated to the fragility of small vessels and the tendency to bleed. Therefore, a substantial number of dotHSs might be associated with a large-sized, deep intracerebral hematoma (ICH). On the other hand, dotHSs may reflect old microbleeds that did not enlarge to symptomatic size. METHODS: To investigate how dotHSs are related to the size (maximal diameter) of primary deep ICH, we analyzed the diameter and the number of dotHSs in 151 patients with deep ICH not associated with subarachnoid hemorrhage or intraventricular hemorrhage (75 males and 76 females, age ranged from 37 to 90 [65.7 +/- 11.3 years old] who were consecutively admitted to Hakodate Municipal Hospital. The hazard ratio (HR) for a maximal diameter of deep ICH < or =2 cm was estimated, using the number of dotHSs and risk factors for stroke. RESULTS: The number of dotHSs associated with the diameter < or =2 cm was 9.2 +/- 11.5, significantly larger than that with the diameter > or =2 cm (4.7 +/- 7.0, P= .012). Multivariate analysis revealed that a maximal diameter of deep ICH of < or =2 cm was found in patients with dotHS (HR, 3.7; 95% confidence interval [CI], 1.4-10.1; P= .009). CONCLUSION: Though small sample size limited the power of our analyses, these findings suggest that the number of dotHSs may be associated with a small diameter of deep ICH. 相似文献
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Twenty-one mature New Zealand white female rabbits were allocated into three groups of seven rabbits. Group I received a bolus of doughy Simplex polymethylmethacrylate (PMMA) cement injected into the proximal tibia through a drill hole. Group II received a preformed, cooled, bulk PMMA pellet. Group III had particulate PMMA powder implanted. The operated, but nonimplanted, left tibiae served as controls. Animals were killed after four months. Histologically, both Group I and Group II demonstrated a thin, fibrous tissue membrane at the implant interface. Particulate PMMA (Group III) stimulated a much thicker, florid, foreign body reaction composed of histiocytes and giant cells. The foreign body response to particulate acrylic cement was similar to that seen in failed cemented joint replacement arthroplasty in humans. 相似文献
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Yuichiro Nakai MD DMSc Takeshi Maeda MD Junko Nishio MD DMSc Daisuke Tachibana MD Motoharu Imanaka MD DMSc Sachio Ogita MD DMSc 《The Australian & New Zealand journal of obstetrics & gynaecology》1998,38(4):469-471
EDITORIAL COMMENT: We accepted this case for publication to remind readers that although uterine rupture during labour in a primigravida is extremely uncommon it does occur, or at any rate nulliparas can develop abdominal pain and shock in labour with a haemoperitoneum resulting from a tear in a vein in the lower posterior uterine wall. When one sees the hugely dilated uterine and ovarian venous plexuses at Caesarean section it is easy to believe that bleeding from such a vessel during labour could be prodigious. This case suggests that a dilated vein with blood flow derangements may be the cause. Nonetheless, as the authors warn us, the necessary response is not a precise diagnosis, but rapid laparotomy. See also Editorial Comment to Chin MMS, Harvey JA, Duffy BL. Uterine rupture during labour in a primigravida. Aust NZ J Obstet Gynaecol 1996; 36: 210. 相似文献
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Taizen Nakase Toshiki Mizuno Sanae Harada Kei Yamada Tsunehiko Nishimura Kotaro Ozasa Yoshiyuki Watanabe Ken Nagata 《Journal of clinical neuroscience》2007,14(10):943-947
While gene polymorphism for angiotensinogen (AGT) is reported to contribute to the regulation of blood pressure and salt sensitivity, its effect on the risk of ischemic stroke remains controversial. We hypothesized that polymorphism of the AGT gene could be a risk factor for ischemic stroke. Major clinical risk factors and the AGT gene M235T polymorphism were examined in 147 consecutive stroke patients and 133 healthy age-matched controls. All patients were categorized into four stroke types (single lacuna, multiple lacunae, large-artery atherosclerosis and branch atheromatous disease in brainstem) and two vascular groups (large and perforating arterial lesions). The AGT gene M allele significantly increased the risk of single lacuna, multiple lacunae and small arterial lesions, in male patients (p=0.029, 0.031 and 0.026, respectively). Synergistic effects of the AGT gene polymorphism and clinical risks were not observed. In conclusion, AGT M allele may present a risk of lacunar infarctions in Japanese men, independent of hypertension. 相似文献