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Yukiko Hasuike Takeshi Nakanishi Rintarou Moriguchi Yoshinaga Otaki Masayoshi Nanami Yasue Hama Miki Naka Koji Miyagawa Masaaki Izumi Yoshihiro Takamitsu 《Nephrology, dialysis, transplantation》2004,19(6):1474-1479
BACKGROUND: Cyanide is a toxic agent, and its detoxification product, thiocyanate, may be a major pathogenetic substance in uraemia. Recent studies examining the myeloperoxidase(MPO)/thiocyanate system have suggested a link between thiocyanate and atherosclerosis. However, inaccuracies in conventional assays for cyanide and thiocyanate have limited the understanding of their metabolism in haemodialysis (HD) patients. METHODS: We used high-performance liquid chromatography to measure cyanide in erythrocytes and thiocyanate in plasma in 43 HD patients and in a group of 46 healthy controls that included 15 current smokers. To clarify the metabolic conversion of cyanide to thiocyanate in uraemic patients, we also measured cysteine and sulfate. We then used stepwise regression analysis to analyse factors that determine erythrocyte cyanide and plasma thiocyanate. RESULTS: Mean cyanide and thiocyanate were significantly greater in HD patients than in non-smoking controls. However, cyanide was far below lethal concentrations in dialysis patients. Thiocyanate was six to seven times greater in HD patients than in non-smoking controls, and decreases in thiocyanate following dialysis were only 19.3+/-3.5%. Multiple regression analysis showed a positive correlation between cyanide and thiocyanate in controls, but a negative correlation in HD patients. In patients, an inverse relationship between thiocyanate and BUN was also observed. CONCLUSIONS: The elevation of thiocyanate in patients undergoing dialysis probably is secondary to both limited efficiency of HD and deranged metabolism of cyanide and thiocyanate. Because thiocyanate is a preferred substrate for MPO, it may play a role in uraemic complications including cardiovascular events. 相似文献
13.
Yoshito Tomimaru Ken Kodama Jiro Okami Kazuyuki Oda Koji Takami Masahiko Higashiyama 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(5):193-198
Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary
resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with
pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had
never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients
were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with
left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right
thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic
patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three
of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial
effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial
effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198) 相似文献
14.
Shigeru Onodera Koji Saito Takafumi Saito Hitoshi Togashi Sumio Kawata Katsuaki Ukai Haruhide Shinzawa 《Nihon Shokakibyo Gakkai zasshi》2007,104(2):213-218
It is well known that long-term infection with Clonorchis sinensis often causes bile duct cancer, usually. It occurs in the intrahepatic bile duct. We encountered a rare case of clonorchiasis complicated with duodenal papillary cancer. The patient was a woman from China. Although clonorchiasis is rarely found in Japan, the promotion of international exchange may increase the number of visitors from endemic areas. Thus we must pay sufficient attention to this disease. Also, we reported that the microplate ELISA technique was useful in the diagnosis of clonorchiasis with high accuracy in this case. 相似文献
15.
Yoshitaka Hirooka Yoshikuni Kimura Masatsugu Nozoe Yoji Sagara Koji Ito Kenji Sunagawa 《Hypertension research》2006,29(1):49-56
Amlodipine is a dihydropyridine calcium channel blocker that is widely used for the treatment of hypertensive patients and has an antioxidant effect on vessels in vitro. The aim of the present study was to examine whether treatment with amlodipine reduced oxidative stress in the brains of stroke-prone spontaneously hypertensive rats (SHRSP). The animals received amlodipine, nicardipine or hydralazine for 30 days in their drinking water. Levels of thiobarbituric acid-reactive substances (TBARS) in the brain (cortex, cerebellum, hypothalamus, and brainstem) were measured before and after each treatment. Systolic blood pressure decreased to similar levels in the amlodipine-, nicardipine-, and hydralazine-treated groups. Urinary norepinephrine excretion was significantly reduced in SHRSP after treatment with amlodipine, but not with nicardipine or hydralazine. Levels of TBARS in the cortex, cerebellum, hypothalamus, and brainstem were significantly higher in SHRSP than in Wistar-Kyoto rats (WKY), and were reduced in amlodipine-treated, but not in nicardipine- or hydralazine-treated, SHRSP. Electron spin resonance spectroscopy revealed increased levels of reactive oxygen species in the brains of SHRSP, which were reduced by treatment with amlodipine. Intracisternal infusion of amlodipine also reduced systolic blood pressure, urinary norepinephrine excretion, and the levels of TBARS in the brain. These results suggested that oxidative stress in the brain was enhanced in SHRSP compared with WKY rats. In addition, antihypertensive treatment with amlodipine reduced oxidative stress in all areas of the brain examined and decreased blood pressure without a reflex increase in sympathetic nerve activity in SHRSP. 相似文献
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17.
Satoru Osuka Shingo Takano Takao Enomoto Eiichi Ishikawa Koji Tsuboi Akira Matsumura 《Child's nervous system》2007,23(8):897-900
Background Although there have been reports dealing with ventricular diverticulum (VD) analyzed by cisternography and computed tomography
(CT), those focusing on magnetic resonance imaging (MRI) or neuroendoscopic findings are rare.
Case report We present a case of noncommunicating hydrocephalus caused by aqueductal stenosis with cystic lesion located in supracerebellar
region. Third ventriculostomy was performed on this case. The conventional CT and MRI were compatible with usual VD, but neuroendoscopic
examination suggested otherwise. The endoscopic view inside of the cystic lesion demonstrated passing veins and no membrane.
We diagnosed this cystic lesion as a unique subtype of advanced VD mimicking spontaneous ventriculostomy. Endoscopic observation
of the cyst was very useful for accurate diagnosis and safe treatment. 相似文献
18.
Hiroaki Yuasa Koji Kawanishi Jun Watanabe 《The Journal of pharmacy and pharmacology》1995,47(7):576-580
The effects of ageing on the oral (gastrointestinal) absorption of d -xylose were investigated by analysing the gastrointestinal disposition after oral administration to young (9 weeks) and old (53 weeks) rats. A linear model assuming first-order gastric emptying followed by first-order intestinal absorption was fitted to remaining fraction vs time profiles for the stomach and small intestine to estimate the gastric emptying rate constant (kg) and the intestinal absorption rate constant (ka). In young and old rats, kg values were 0·087 ± 0·008 and 0·070 ± 0·007 min?1, respectively, and ka values were 0·020 ± 0·002 and 0·018 ± 0·002 min?1 suggesting an insignificant effect on ageing on the rate of oral absorption. The average intestinal lumen volume (Vav) was unchanged with ageing, and so was the apparent intestinal membrane permeability clearance (CLapp) as the product of ka and Vav. However, the small intestinal transit time (Tsi) was suggested to be twice that in older rats (171 min) than in young rats (78 min) by the analysis of gastrointestinal disposition of inulin, a non-absorbable marker. It was also shown that our preceding finding of an increase in the fraction absorbed of D-xylose with ageing can be solely ascribable to the delay in intestinal transit. Thus, among various determinants of oral absorption, only Tsi was found to be altered with ageing. The CLa,app and ka of passively absorbed drugs such as D-xylose may be generally unchanged, and the fraction absorbed may increase with ageing by the delay in intestinal transit. 相似文献
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20.
Kazuki Tamura Tadayuki Oka Kazutaka Ohsawa Takehiko Koji Yoji Watanabe Shigeru Katamine Hiroshi Sato Hiroyoshi Ayabe 《The Journal of heart and lung transplantation》2003,22(4):452-459
BACKGROUND: Cytomegalovirus (CMV) diseases commonly occur in allograft recipients in the early post-transplant period. However, factors responsible for the high incidence of CMV diseases during this period are not yet fully defined. METHODS: Wistar-Furth (WF; RT-1(u)) rats were inoculated with 10(4) plaque-forming units (PFU) of rat CMV (RCMV) intraperitoneally, and then transplanted with allogeneic lungs from Dark Agouti (DA; RT-1avl) rats or stimulated with 10(7) mitomycin C-treated spleen cells from DA rats by daily sub-cutaneous injections for 2 weeks. No immunosuppressive agent was used. Naive WF rats and WF rats grafted with syngeneic lungs or cells were used as controls. The level of RCMV replication in rats was assessed by infectious virus titers in tissues. RESULTS: The virus titers in salivary glands of allogeneic and syngeneic lung graft recipients were significantly higher than in naive WF rats. The level of RCMV replication in rats stimulated with allogeneic spleen cells was significantly higher than in the syngeneic recipient rats: virus titers in the salivary gland of allogeneic and syngeneic recipients reached 4.61 +/- 0.33 and 4.00 +/- 0.37 log(10) PFU/g tissue, respectively, at 14 days post-infection (p = 0.015). The augmented viral replication in allogeneic recipients was confirmed by an increase in the number of RCMV antigen-positive macrophages present in tissue sections of the salivary gland. CONCLUSIONS: Acute lung allograft rejection and allogeneic spleen cell stimulation enhance CMV replication in the salivary gland of rats. Various responses to allogeneic antigens occurring in the process of acute allograft rejection could be risk factors for post-transplant CMV replication and infection. 相似文献