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61.
62.
Takashi Akasaki Yusuke Ohya Junya Kuroda Kimika Eto Isao Abe Hideki Sumimoto Mitsuo Iida 《Hypertension research》2006,29(10):813-820
Although vascular cells express multiple members of the Nox family of nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase, including gp91phox, Nox1, and Nox4, the reasons for the different expressions and specific roles of these members in vascular injury in chronic hypertension have remained unclear. Thus, we quantified the mRNA expressions of these NAD(P)H oxidase components by real-time polymerase chain reaction and evaluated superoxide production and morphological changes in the aortas of 32-week-old stroke-prone spontaneously hypertensive rats (SHRSP) and age-matched Wistar Kyoto rats (WKY). The aortic media of SHRSP had an approximately 2.5-fold greater level of Nox4 mRNA and an approximately 10-fold greater level of Nox1 mRNA than WKY. The mRNA expressions of gp91phox and p22phox in SHRSP and WKY were comparable. SHRSP were treated from 24 weeks of age for 8 weeks with either high or low doses of candesartan (4 mg/kg/day or 0.2 mg/kg/day), or a combination of hydralazine (30 mg/kg/day) and hydrochlorothiazide (4.5 mg/kg/day). The high-dose candesartan or the hydralazine plus hydrochlorothiazide decreased the blood pressure of SHRSP to that of WKY, whereas the low-dose candesartan exerted no significant antihypertensive action. Media thickening and fibrosis, as well as the increased production of superoxide in SHRSP, were nearly normalized with high-dose candesartan and partially corrected with low-dose candesartan or hydralazine plus hydrochlorothiazide. These changes by antihypertensive treatment paralleled the decrease in mRNA expression of Nox4 and Nox1. These results suggest that blood pressure and angiotensin II type 1 receptor activation are involved in the up-regulation of Nox1 and Nox4 expression, which could contribute to vascular injury during chronic hypertension. 相似文献
63.
Yu-Yan Fan Ryoko Baba Yukiko Nagai Akira Miyatake Naohisa Hosomi Shoji Kimura Guang-Ping Sun Masakazu Kohno Mamoru Fujita Youichi Abe Akira Nishiyama 《Hypertension research》2006,29(3):169-178
Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury. 相似文献
64.
The nonimprovement group was characterized by the following: ① a high incidence of diabetes (4 of 6 patients) ,② a high incidence of preexisting cardiac dysfunction documented prior to or at the time of induction of 相似文献
65.
Squamous cell carcinoma of the thyroid--a report of three cases 总被引:1,自引:0,他引:1
A Tsuchiya S Suzuki T Nomizu Y Yamaki R Abe S Katayama 《The Japanese journal of surgery》1990,20(3):341-345
Three cases of squamous cell carcinoma of the thyroid are reported herein. In all cases, the carcinoma occurred in old age and was characterized by a rapidly growing tumor, usually associated with dyspnea and dysphagia. The prognosis of all 3 cases was poor, with a mean survival of only 6.3 months. Although squamous metaplasia is an accepted etiology of this disease, clinical investigation of the cases presented here does not favor it in consideration of the clinical features of papillary carcinoma of the thyroid with squamous metaplasia. The histological findings of our cases revealed areas of cystic formation, suggesting that some of these carcinomas may be derived from remnants of embryonic origin. 相似文献
66.
K Sasai H Iwai T Yoshizawa S Nishimoto Y Shibamoto Y Kitakabu N Oya M Takahashi M Abe 《International journal of radiation biology》1992,62(2):221-227
We have previously reported that KU-2285, a 2-nitroimidazole with a fluorinated N1-substituent (-CH2-CF2CONH(CH2)nOH, n = 2), was a promising hypoxic cell radiosensitizer. In this study the pharmacokinetics of KU-2285 and its related compounds (n = 3 and n = 4) were compared with those of etanidazole (a 2-nitroimidazole with an N1-substituent of -CH2CONH(CH2)nOH, n = 2) and its related compounds (n = 3 and n = 4) to assess the effects of incorporation of a CF2 group. The lipophilicity of the fluorinated compounds was higher than that of etanidazole, as measured by the octanol/water partition coefficient. As the number of CH2 groups increased, the lipophilicity of the compounds in both the KU-2285 and etanidazole series increased. The brain tissue levels of the fluorinated compounds were as low as those of the etanidazole derivatives, while the biological half-lives of the fluorinated compounds in peripheral nervous tissues were shorter than those of related non-fluorinated compounds. 相似文献
67.
Fumio Yamauchi Yoshihiro Takebayashi Takaya Abe Toshinari Muramatsu Rika Murakami Masaki Ohtsuka Masayuki Endoh Yasuo Nomoto Hideto Sakai Miho Hida 《Clinical and experimental nephrology》1997,1(3):243-246
A 52-year-old woman who had had 6 months of chemotherapy using mitomycin C and cisplatin for cervical cancer presented with
hemolytic uremic syndrome. Conventional plasmapheresis using whole-plasma fraction was ineffective. However, plasmapheresis
using the cryosupernatant fraction dramatically improved symptoms of hemolytic anemia and thrombocytopenia in this case. The
activity of factor VIII in the cryosupernatant fraction of plasma as a replacement fluid decreased after removal of cryoprecipitate,
indicating effective removal of von Willebrand factor. The pathogenesis of her hemolytic uremic syndrome may have been associated
with von Willebrand factor multimers contained in the cryoprecipitate of plasma. Similar use of the cryosupernatant fraction
of plasma could not be found in other reports of cases of hemolytic uremic syndrome. Plasmapheresis using the cryosupernatant
fraction of plasma may improve refractory hemolytic uremic syndrome. 相似文献
68.
A total number of 427 patients with tetralogy of Fallot who underwent corrective surgery between 1960 and March 1990, in whom 211 patients who survived the surgery over 10 years were evaluated for the follow-up studies. Hemodynamic and cardiac function studies were carried out in 101 patients at the mean interval of 15.7 years (ranges 2 to 21 years). Three methods indicated that patients with muscle resection and pulmonary valvulotomy without patch enlargement (NP) had worse results than the groups with RV patch below valve (RP) and with transannular patch (TP). Also, Holter ECG revealed ventricular arrhythmias in patients with NP were more common than the groups with RP and TP. Sixteen patients (13 with NP, 2 with TP and one with RP) were required reoperation for residual ventricular shunt in 13, residual pulmonary stenosis in 11 and tricuspid regurgitation in 2. All of these 16 patients survived operation and obtained excellent clinical status. It is concluded that patients with TOF after corrective surgery should be carefully followed with short term interval to prevent sudden death and postoperative complications. 相似文献
69.
HTX rat, a congenital hydrocephalic strain, develops ventricular dilatation and cystic cavities in the cerebral white matter after birth. To investigate the reactive changes in glial cells around these cavities, immunohistochemical staining for glial fibrillary acidic protein (GFAP), a specific marker protein of astrocytes, and bromodeoxyuridine (BrdU), a thymidine analogue, was carried out on 107 Wistar and HTX rat brains from birth to postnatal day (P) 26. Animals were divided into three groups: Group A, Wistar rats as normal controls; Group B, HTX rats with a normal structure or only mild ventricular dilatation without any lesion in the white matter; and Group C, HTX rats with severe ventricular dilatation and cyst formation in the white matter. Group B rats showed similar development of GFAP-positive (GFAP+) cells to that in Group A rats, both morphologically and quantitatively. On the other hand, Group C rats showed definite structural changes in GFAP+ cells around the cystic cavities from P5. These included enriched cytoplasm and thickened cell processes with increased GFAP expression, and enveloped most cyst walls from P10. However, quantitative examination of the percentage of GFAP+ cells in Group C rats showed a similar developmental profile to those in Group A and B rats. Furthermore, the labeling index of BrdU-positive cells, indicating S-phase cells, in the white matter in Group C rats showed a similar decreasing pattern to that in Group A and B rats from P1 to P26.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
70.
Y Muraki T Kobayashi H Kojima A Shibuya T Nagasawa T Abe N Mori 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1992,33(3):328-332
A 50-year-old woman with anorexia nervosa was admitted for evaluation of neutropenia (WBC 1,600/microliters). Her bone marrow was gelatinous, and myeloid cells had decreased. Homogeneous substance deposited in the marrow, stained by alcian blue (pH 2.5), indicative of acid mucopolysaccharides. CFU-G and CFU-GM were decreased in number and myeloid pool in the bone marrow also decreased. Anti-neutrophilic antibody was negative. Neutropenia may be related to myeloid hypoplasia, due to increase of acid mucopolysaccharides replacing adipose cells in the bone marrow under long-term mal-nutritional state. Neutrophils markedly increased by administration of rhG-CSF 5.0 micrograms/kg/day for 14 days without the first peak. Serum G-CSF level did not increase (less than 60 pg/ml). It is effective to administer G-CSF to anorexia nervosa with neutropenia. 相似文献