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61.
Yu Y Ohmori K Chen Y Sato C Kiyomoto H Shinomiya K Takeuchi H Mizushige K Kohno M 《Journal of the American College of Cardiology》2004,44(4):904-913
OBJECTIVES: We examined the effects of early treatment with a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor pravastatin on the progression of glucose intolerance and cardiovascular remodeling in a model of spontaneously developing type II diabetes mellitus (DM), the Otsuka Long-Evans Tokushima Fatty (OLETF) rats. BACKGROUND: Clinical trials showed that pravastatin prevented new-onset DM in hypercholesterolemic patients, and that it was effective in prevention of cardiovascular events in diabetics. METHODS: The OLETF rats were treated with pravastatin (100 mg/kg/day) from 5 weeks of age and compared with age-matched untreated OLETF rats and normal Long-Evans Tokushima Otsuka (LETO) rats on serial oral glucose tolerance tests (OGTT) and Doppler echocardiography and on histopathological/biochemical analyses of the heart at 30 weeks. RESULTS: The OGTT revealed that 40% and 89% of untreated OLETF rats were diabetic at 20 and 30 weeks, respectively, but 0% and only 30%, respectively, were diabetic in the treated OLETF. Left ventricular diastolic function was found impaired from 20 weeks in untreated OLETF but remained normal in the treated-OLETF. The wall-to-lumen ratio and perivascular fibrosis of coronary arteries were increased in untreated-OLETF but were limited in the treated-OLETF at 30 weeks. Moreover, cardiac expressions of a fibrogenic growth factor, transforming growth factor-beta1 (TGF-beta1), and a proinflammatory chemokine, monocyte chemoattractant protein-1 (MCP-1), were increased in untreated-OLETF. However, in the treated-OLETF, overexpressions of TGF-beta1 and MCP-1 were attenuated, which was associated with overexpression of endothelial nitric oxide synthase (eNOS) (2.5-fold of control LETO). CONCLUSIONS: Early pravastatin treatment prevented cardiovascular remodeling in the spontaneous DM model by retarding the progression of glucose intolerance, overexpressing cardiac eNOS, and inhibiting overexpressions of fibrogenic/proinflammatory cytokines. 相似文献
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63.
Sakamoto S Yokoyama M Zhang X Prakash K Nagao K Hatanaka T Getzenberg RH Kakehi Y 《Endocrinology》2004,145(6):2929-2940
Lysophosphatidic acid (LPA) is an endogenous lipid growth factor that is thought to play important roles in cell proliferation and antiapoptosis and therefore may have roles in the development and progression of benign prostatic hyperplasia (BPH). CYR61 (CCN1), on the other hand, is a growth factor-inducible immediate early gene that functions in cell proliferation, differentiation, and extracellular matrix synthesis. Here we show the close relationship between LPA-induced expression of CYR61 and prostate enlargement. CYR61 mRNA and protein were dramatically up-regulated by 18:1 LPA (oleoyl-LPA) within 1 and 2 h, respectively, in both stromal and epithelial prostatic cells. G protein-coupled receptors, i.e. Edg-2, Edg-4, and Edg-7, for LPA were also expressed in both stromal and epithelial prostatic cells. Furthermore, on DNA microarray analysis for normal and BPH patients, CYR61 was found to be related to the development and progression of BPH, regardless of symptoms. Although CYR61 mRNA was synthesized in hyperplastic epithelial cells, in many cases of BPH, CYR61 protein was detected in both the epithelial and stromal regions of BPH patient tissues. The functional contribution of CYR61 to prostatic cell growth was demonstrated by recombinant CYR61 protein and anti-CYR61 neutralizing antibodies, which inhibited CYR61-dependent cell spreading and significantly diminished cell proliferation, respectively. In conclusion, these data support the hypothesis that LPAs induce the expression of CYR61 by activating G proteincoupled receptors and that CYR61 acts as a secreted autocrine and/or paracrine mediator in stromal and epithelial hyperplasia, demonstrating the potential importance of this signaling mechanism in the disease. 相似文献
64.
Daimon Y Tanaka K Watanabe K 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》2008,82(3):205-212
Cigar-shaped clostridia such as Clostridium clostridioforme and Clostridium symbiosum have been found in serious infections such as bacteremia. In Japan, however, these strains are unrecognized as clinically significant because they are overlooked as unidentified gram-negative rods. We isolated 60 strains of cigar-shaped Clostridium spp. from 48 clinical specimens treated at our laboratory from November 2004 to September 2006. Of these, 19 (39.6%) were primary infections and 29 (60.4%) postsurgical. Primary infections included infected decubitus ulcer (7), peritonitis, intra abdominal abscess, sepsis (2 cases in each group), pyometra, Bartholin's gland abscess, and Fournier's gangrene (1 case in each group). Secondary infections included 28 cases of surgical site infection and 1 case of pyothorax. CRP in 30 cases (62.5%) exeeded 10 mg/dL. In 26 (54.2%), WBC exceeded 12,000/microL. The 60 isolated strains were as follows by 16S rRNA sequencing: Clostridium hathewayi (26.7%), C. clostridioforme (16.7%), Clostridium bolteae (18.3%), Clostridium citroniae (10%), Clostridium aldenense (8.3%), and Clostridium symbiosum (20%). In antimicrobial susceptibility, strains of C. hathe-wayi showed relatively higher MIC for cefotaxime (MIC50; 64 microg/mL, MIC90; 128 microg/mL). Three strains of C. bolteae were beta-lactamase-producing and their MICs for ampicillin exceeded 128 microg/mL. 相似文献
65.
Hideaki Kanki Hideo Mitamura Seiji Takatsuki Kouichiro Sueyoshi Kaori Shinagawa Toshiaki Sato Satoshi Ogawa 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1998,12(5):475-482
The antifibrillatory effect of pilsicainide, a sodium channel blocker with slow recovery kinetics, was investigated in a canine model of atrial fibrillation. Prolonging the atrial effective refractory period is an important mechanism for pharmacological termination of atrial fibrillation. However, the effectiveness of potassium channel blockers has been questioned because of their reverse-use–dependent property. In eight open-chest dogs, the duration of the atrial endocardial monophasic action potential and the atrial effective refractory period were determined using a Franz catheter. Conduction velocity was obtained from a 96-channel mapping electrode at multiple cycle lengths. Inducibility of sustained atrial fibrillation (>30 minutes) was confirmed by atrial burst pacing during bilateral vagal stimulation, and local fibrillation cycle lengths were measured. Five minutes after restarting fibrillation, pilsicainide (0.6 mg/kg + 0.04 mg/kg/min) was administered. After fibrillation was terminated, measurements were repeated. Pilsicainide successfully terminated atrial fibrillation in 7 of 8 dogs after the median time of 5.1 minutes. The conduction velocity decreased significantly. Although pilsicainide did not affect monophasic action potential duration, it caused use-dependent prolongation of the atrial effective refractory period (P < 0.05), creating postrepolarization refractoriness. Accordingly, pilsicainide prolonged the atrial fibrillation cycle length from 80.6 to 113.8 ms (P < 0.05) before termination of fibrillation. Sodium channel blockers with slow recovery kinetics can prolong the atrial effective refractory period without affecting monophasic action potential duration. Unlike potassium channel blockers, these sodium channel blockers maintain postrepolarization refract 相似文献
66.
Cribriform-morular variant of papillary carcinoma is a distinctive histological variant of thyroid cancer, characterized by intermingled cribriform, follicular, papillary, trabecular, and morular architecture. These tumors are known to be associated with familial adenomatous polyposis (FAP), but are also encountered in non-FAP patients. The authors report on ultrastructural and genetic studies of 3 patients with this type of carcinoma-associated FAP. There were numerous microfilaments approximately 100?nm long at the nuclear clearing area of the morular regions. Two of the 3 patients showed germline APC mutations, and 1 had so somatic APC mutation. Both mutations were in previously unreported regions. The study provides new information for understanding the development of this rare tumor. 相似文献
67.
68.
Azumi Ishizaki Kaori Matsushita Huyen Thi Thanh Hoang Dorothy M. Agdamag Cuong Hung Nguyen Vuong Thi Tran Toshiyuki Sasagawa Kunikazu Saikawa Raphael Lihana Hung Viet Pham Xiuqiong Bi Van Thanh Ta Thuc Van Pham Hiroshi Ichimura 《Journal of medical virology》2013,85(6):1069-1076
Human papillomavirus (HPV) has several intragenotypic variants with different geographical and ethnic distributions. This study aimed to elucidate the distribution patterns of E6 and E7 (E6/E7) intragenotypic variants of HPV type 16 (HPV‐16), which is most common worldwide, and HPV‐52, which is common in Asian countries such as Japan, the Philippines, and Vietnam. In previous studies, genomic DNA samples extracted from cervical swabs were collected from female sex workers in these three countries and found to be positive for HPV‐16 or HPV‐52. Samples were amplified further for their E6/E7 genes using type‐specific primers and analyzed genetically. Seventy‐nine HPV‐16 E6/E7 genes were analyzed successfully and grouped into three lineages: European (Prototype), European (Asian), and African‐2. The prevalences of HPV‐16 European (Prototype)/European (Asian) lineages were 19.4%/80.6% (n = 31) in Japan, 75.0%/20.8% (n = 24) in the Philippines, and 0%/95.8% (n = 24) in Vietnam. The 109 HPV‐52 E6/E7 genes analyzed successfully were grouped into four lineages, A–D; the prevalences of lineages A/B/C/D were, respectively, 5.1%/92.3%/0%/2.6% in Japan (n = 39), 34.4%/62.5%/0%/3.1% in the Philippines (n = 32), and 15.8%/73.7%/7.9%/2.6% in Vietnam (n = 38). The distribution patterns of HPV‐16 and HPV‐52 lineages in these countries differed significantly (P < 0.000001 and P = 0.0048, respectively). There was no significant relationship between abnormal cervical cytology and either HPV‐16 E6/E7 lineages or specific amino acid mutations, such as E6 D25E, E6 L83V, and E7 N29S. Analysis of HPV‐16 and HPV‐52 E6/E7 genes can be a useful molecular‐epidemiological tool to distinguish geographical diffusion routes of these HPV types in Asia. J. Med. Virol. 85: 1069–1076, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
69.
Kaijun Niu Hui Guo Masako Kakizaki Yufei Cui Kaori Ohmori-Matsuda Lei Guan Atsushi Hozawa Shinichi Kuriyama Toru Tsuboya Takashi Ohrui Katsutoshi Furukawa Hiroyuki Arai Ichiro Tsuji Ryoichi Nagatomi 《Journal of affective disorders》2013,144(1-2):165-170
BackgroundEnhanced oxidative stress or defective anti-oxidant defenses are related to the pathogenesis of depressive symptoms. Lycopene is the most powerful antioxidant amongst the carotenoids. The aim of this study was to investigate the relationship between different vegetables, including tomatoes/tomato products (a major source of lycopene), and depressive symptoms in a community-based elderly population.MethodsWe analyzed a cross-sectional survey including 986 community-dwelling elderly Japanese individuals aged 70 years and older. Dietary intake was assessed using a valid self-administered diet-history questionnaire, and depressive symptoms were evaluated using the 30-item Geriatric Depression Scale with 2 cut-off points: 11 (mild and severe) and 14 (severe) or use of anti-depressive agents.ResultsThe prevalence of mild and severe and severe depressive symptoms was 34.9% and 20.2%, respectively. After adjustments for potentially confounding factors, the odds ratios of having mild and severe depressive symptoms by increasing levels of tomatoes/tomato products were 1.00, 0.54, and 0.48 (p for trend <0.01). Similar relationships were also observed in the case of severe depressive symptoms. In contrast, no relationship was observed between intake of other kinds of vegetables and depressive symptoms.LimitationsThis is a cross-sectional study, and not for making a clinical diagnosis of depressive episodes.ConclusionsThis study demonstrated that a tomato-rich diet is independently related to lower prevalence of depressive symptoms. These results suggest that a tomato-rich diet may have a beneficial effect on the prevention of depressive symptoms. Further studies are needed to confirm these findings. 相似文献