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1.
Katsuo Kamata Ayako Makino Noriyasu Kanie Shu-ichi Oda Takayuki Matsumoto Tsuneo Kobayashi Toyohiko Kikuchi Masato Nishimura Toshio Honda 《Journal of Smooth Muscle Research》2006,42(2-3):75-88
Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders. 相似文献
2.
Yukiko Kaizu Sakae Ohkawa Hiromichi Kumagai 《Nephrology, dialysis, transplantation》2002,17(3):442-448
BACKGROUND: Measurement of muscle mass is useful for evaluating protein nutritional status. Various methods for estimating muscle mass in haemodialysis patients have recently been developed. METHODS: The validity of the estimate of creatinine production calculated with the creatinine kinetic model (CKM) was examined in 46 haemodialysis patients by comparing it with the actual creatinine production, this being determined from the sum of creatinine appearing in the dialysate and the estimated metabolic degradation. The correlation of various other muscle mass indices with creatinine production was also investigated in these patients. RESULTS: The estimate of creatinine production using CKM was significantly correlated with creatinine production calculated from the spent dialysate plus an estimate for the extra-renal creatinine degradation (r=0.90, P<0.001). A Bland-Altman analysis revealed that the mean prediction error for the estimate of creatinine production by CKM was +0.10 g/day and the limits of agreement were +0.34 to -0.14 g/day. The cross-sectional area of the thigh muscle measured by computed tomography (CT) was also significantly correlated with creatinine production (r=-0.86, P<0.01). In contrast, the correlations of 3-methylhistidine production measured in the spent dialysate, the mid-upper arm muscle circumference and the skeletal muscle mass estimated by an anthropometric prediction model with creatinine production were lower (r<0.82). CONCLUSION: Creatinine production calculated using CKM and CT measurement of thigh muscle area are valid methods for estimating muscle mass during routine clinical examinations of haemodialysis patients. 相似文献
3.
K Kuboki M Sakai I Kuwajima S Maeda S Ohkawa K Ueda K Kuramoto 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(5):390-395
In order to investigate whether intravenous bolus injection of isosorbide dinitrate (ISDN) is a safe and efficient therapy in aged patients with congestive heart failure, we studied acute hemodynamic effects in 11 patients. Peak effects on preload were observed after 5 to 10 minutes of bolus injection and unloading effects continued effectively for 60 minutes. At peak effect, pulmonary systolic pressure decreased from 50.2 +/- 2.6 to 36.2 +/- 2.6 mmHg (-28.5%, p less than 0.01) and pulmonary end diastolic pressure decreased from 25.0 +/- 2.2 to 18.5 +/- 2.1 mmHg (-26.0%, p less than 0.01). Mean pulmonary artery wedge pressure decreased from 23.4 +/- 2.2 to 16.0 +/- 2.1 mmHg (-31.6%, p less than 0.01). Mean right atrial pressure decreased from 10.5 +/- 1.8 to 7.4 +/- 2.0 mmHg (-29.5%, p less than 0.01). Blood pressure, heart rate, cardiac index, systemic and pulmonary vascular resistance showed no significant changes. Thus, intravenous bolus injection of ISDN showed a potent vasodilator effects on preload, and may be a safe and useful treatment for aged patients with acute congestive heart failure. 相似文献
4.
Y Miyazaki S Ebisuno Y Uekado T Ogawa A Senzaki T Ohkawa 《The Journal of urology》1986,135(1):107-109
Uterus didelphys with unilateral imperforate vagina is rare. Interestingly, in all reported cases in which the urinary tract was investigated renal agenesis was found on the side of the obstructed hemivagina. We report 2 cases of this unusual and interesting condition, and review the embryogenesis of müllerian duct abnormalities associated with renal agenesis, as well as the clinical findings, diagnosis and management. We stress the importance of prompt and accurate diagnosis, and treatment as a means to avoid unnecessary surgical procedures. 相似文献
5.
Efficacy of SIV/deltaB670 glycoprotein-enriched and glycoprotein-depleted subunit vaccines in protecting against infection and disease in rhesus monkeys 总被引:11,自引:0,他引:11
M Murphey-Corb R C Montelaro M A Miller M West L N Martin B Davison-Fairburn S Ohkawa G B Baskin J Y Zhang G B Miller 《AIDS (London, England)》1991,5(6):655-662
Immunization with an inactivated whole-virus vaccine is highly effective in preventing lentivirus infection. The viral protein(s) essential to the induction of protective responses, however, have not been identified. To define the role of virion components in the induction of protective immunity, we evaluated the efficacy of glycoprotein-enriched and glycoprotein-depleted simian immunodeficiency virus (SIV) subunit vaccines prepared by lentil-lectin affinity chromatography of gradient-purified virions using the immunization and challenge regimen previously found successful with an inactivated whole-virus vaccine. Infection was determined by successful recovery of virus, the induction of SIV-specific antibody responses, and infection of naive recipients by inoculation with lymph-node-derived lymphocytes from the vaccinates. Immunization with the glycoprotein-enriched preparation prevented infection in two out of four monkeys, whereas the glycoprotein-depleted vaccine failed to prevent infection in all four vaccinates tested. However, the glycoprotein-depleted vaccine appeared to moderate the progression of SIV-induced disease compared with non-immunized infected control monkeys inoculated with the same challenge dose. These data suggest that subunit vaccines containing sufficient quantities of viral glycoproteins can protect against SIV infection, whereas subunit vaccines composed predominantly of viral core proteins cannot. The development of effective vaccines against HIV infection should include studies on the optimum presentation of the viral envelope glycoproteins to produce long-term broadly protective immune responses. 相似文献
6.
To investigate the mechanism underlying increased endothelin-1 (ET-1) release in diabetic rats, we administered L-arginine chronically to streptozotocin (STZ)-induced diabetic rats. The plasma concentrations of glucose, ET-1 and NOx (NO2- + NO3-) were all significantly raised at 10 weeks after the STZ injection. Chronic administration of L-arginine resulted in a significantly higher plasma NOx concentration and a significantly lower plasma ET-1 level at 10 weeks compared with the untreated diabetic group. ET-1 induced a biphasic vasodilator/vasoconstrictor response in the perfused isolated mesenteric arterial beds from all groups. The vasodilatation was significantly greater in diabetic rats than in age-matched controls. Chronic oral L-arginine administration had no significant effect on the enhanced ET-1-induced vasodilatation seen in the untreated diabetic rats. The vasoconstrictions induced by ET-1 and methoxamine were significantly attenuated in STZ-diabetic rats. The attenuated vasoconstrictor response to ET-1, but not that to methoxamine, was further attenuated by chronic treatment with L-arginine. We conclude that since chronic L-arginine administration not only reduced the increase in plasma ET-1 levels but also further attenuated the ET-1-induced vasoconstriction without affecting the change in vasodilatation, chronic L-arginine administration could be valuable for the treatment of the symptoms of diabetic mellitus related to ET-1. 相似文献
7.
Y Ohkawa H Isoda S Hasegawa Y Furuya M Takahashi M Kaneko 《Journal of computer assisted tomography》1992,16(3):475-477
Thoracic outlet syndrome is a disorder caused by neurovascular compression of the brachial nerve plexus and the subclavian artery or vein by bones and muscles. We report the MR angiographic findings of a patient with thoracic outlet syndrome. 相似文献
8.
M Ohkawa N Fujiwara M Tanabe H Takashima K Satoh Y Mori Y Honjo S Nagao 《AJNR. American journal of neuroradiology》1997,18(2):324
We report a case of benign osteoblastoma arising in the temporal bone of a 28-year-old woman. Plain radiography showed a mass with an amorphous calcified matrix and a thin radiolucent marginal zone. CT and MR imaging were useful in delineating the extent of the tumor, and angiography showed its hypervascularity. Preoperative transarterial embolization was effective in reducing bleeding during surgery. 相似文献
9.
10.
Y Terao I Kuwajima Y Suzuki S Ueda M Sakai S Ohkawa S Matsushita K Kuramoto 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(6):498-502
The clinical features of congestive heart failure in the elderly were investigated in 104 patients (57 males, 47 females, mean age of 79.2). Patients were divided into two subgroups, the readmission group, 33 patients who were readmitted within 6 months after discharge, and the non-readmission group. Chief complaints were dyspnea, edema, chest pain, loss of appetite, chest compression, and palpitation. Heart failure was caused by infection, myocardial ischemia, arrhythmia, inappropriate drug usage including poor drug compliance, the use of beta-blockers, excessive intake of sodium, and anemia. Careful use of drug was essential especially in the readmission group. Major underlying heart disease were ischemic heart disease (39.4%), valvular disease (26.9%), hypertensive heart disease (9.6%), with cardiomyopathy, congenital heart disease seen in the minority. There was no statistically significant difference in underlying heart diseases between the two groups. Supraventricular arrhythmias such as atrial fibrillations, paroxysmal atrial fibrillations, paroxysmal supraventricular tachycardias, and premature atrial contractions were noted in 85.3% of the cases. Drugs for treatment were diuretics, digitalis, isosorbide dinitrate, calcium antagonists. ACE inhibitors and alpha-blockers were also used, showing that vasodilators were more extensively used than before. The major complications were hypertension (39.4%), renal dysfunction (27.9%), cerebrovascular disease (26.9%), diabetes mellitus (16.5%), arteriosclerosis obliterans (7.7%). Renal dysfunction, arteriosclerosis obliterans was seen significantly more frequently in the readmission group. The prognosis at one year after admission was significantly worse in the readmission group. In summary, the major underlying diseases were ischemic heart disease, valvular disease, and hypertensive heart disease. Ischemic heart disease was seen more frequently than in previous investigations at our hospital.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献