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11.
12.
Hiroshi Yamamoto Shinji Teramoto Yasuhiro Yamaguchi Yasuyoshi Ouchi 《Hypertension research》2007,30(11):1065-1076
Obstructive sleep apnea syndrome (OSAS) is recognized as one of the risk factors of hypertension and cardiovascular disorders. In the current study, we hypothesized that the hypoxic stress and oxidative stress caused by obstructive sleep apnea would increase circulating adrenomedullin (ADM) levels in untreated OSAS patients as compared to an age and body mass index (BMI)-matched control group and an age-matched, but normal-BMI control group. We further hypothesized that nasal continuous positive airway pressure (nCPAP) treatment may decrease OSAS-induced hypoxic stress, oxidative stress and ADM levels. To examine these hypotheses, we measured circulating ADM and reactive oxygen species (ROS) from leukocytes before and after nCPAP therapy in OSAS patients. The circulating levels of ADM and amount of ROS in untreated OSAS patients were significantly greater than those in the controls. No differences in ADM levels were found between the increased-BMI controls and normal-BMI controls. We observed that nCPAP treatment decreased sleep apneas, nocturnal oxyhemoglobin desaturation, the circulating ADM, and ROS production by leukocytes in OSAS patients. The ADM levels were associated with the magnitude of oxyhemoglobin desaturation rather than the number of sleep apneas. These observations suggest that nCPAP therapy could reduce OSAS-induced nocturnal hypoxemia, generation of ROS, and ADM in patients with OSAS. 相似文献
13.
K. Kim T. Mizunari N. Mizutani S. Kobayashi K. Takizawa H. Kamiyama Y. Murai A. Teramoto 《Acta neurochirurgica》2006,148(3):353-357
Summary We describe a giant aneurysm of the anterior communicating artery (ACoA) which was treated with a STA-RA graft-A3 bonnet bypass
and A3–A3 side-to-side anastomosis. A giant and partially thrombosed ACoA aneurysm was partially coated 3 years before his
current presentation, its gradual increase producing visual field disturbances. An A3–A3 side-to-side anastomosis and STA-RA
graft-A3 bonnet bypass were performed. The aneurysm was dissected, and the thrombus removed under transient parent-artery
occlusion. The aneurysmal neck was successfully clipped without encountering ischemic changes. This strategy may be useful
for treating giant or thrombosed aneurysms in the region of the ACoA. 相似文献
14.
Keiichiro Yoshinaga Chietsugu Katoh Kazuyuki Noriyasu Yasuyoshi Iwado Hideto Furuyama Yoshinori Ito Yuji Kuge Tetsuro Kohya Akira Kitabatake Nagara Tamaki 《Journal of nuclear cardiology》2003,10(3):275-283
BACKGROUND: Myocardial perfusion single photon emission computed tomography (SPECT) occasionally fails to detect coronary stenosis in patients with coronary artery disease (CAD). We evaluated coronary flow reserve (CFR) using oxygen 15-labeled water in areas with and without ischemia on technetium 99m tetrofosmin stress perfusion SPECT in patients with angiographically documented CAD. METHODS AND RESULTS: Twenty-seven patients with CAD and eleven age-matched normal subjects were studied. Baseline myocardial blood flow (MBF) and MBF during hyperemia induced by intravenous adenosine triphosphate infusion (0.16 mg. kg(-1). min(-1)) were determined with the use of O-15-labeled water positron emission tomography, and the CFR was calculated. Tc-99m tetrofosmin stress/rest SPECT was performed for comparison. On the basis of the results of coronary angiography and SPECT, coronary segments were divided into 3 types: segments with coronary stenosis and a perfusion abnormality on stress SPECT imaging (group A, n = 16), segments with coronary stenosis without a perfusion abnormality (group B, n = 42), and remote segments with no coronary stenosis or perfusion abnormality (group C, n = 18). Baseline MBF values were similar among the 3 groups. CFR in group A was lower (1.82 +/- 0.54) than in group B (2.22 +/- 0.87, P <.05), in group C (2.92 +/- 1.21, P <.01), and in normal segments (3.86 +/- 1.24, P <.001). CFR in group B was lower than in group C (P <.02) and in normal segments (P <.001). CFR in group C was lower than in normal segments (P <.02). CONCLUSIONS: Areas with a perfusion abnormality on stress SPECT had reduced CFR. In the areas without a perfusion abnormality and with coronary stenosis, lowering of CFR was intermediate between the areas with a perfusion abnormality and remote segments. Moreover, CFR was slightly, but significantly, lower in remote segments in patients with CAD compared with normal segments. 相似文献
15.
Nobuyuki Oka Teruaki Kawasaki Kotaro Mizutani Hiroshi Sugiyama Ichiro Akiguchi 《Neuropathology》2007,27(6):509-515
Neuromuscular biopsy is still an essential method for diagnosing vasculitic neuropathy, although its diagnostic sensitivity is at most 60%. Our objective was to examine the expression of hypoxia‐inducible factor 1α (HIF‐1α) in peripheral nerves and to evaluate its usefulness in diagnosing vasculitic neuropathy, especially for discrimination from other axonal neuropathies. Forty‐one patients with vasculitic neuropathy consisting of 20 definite, 14 probable and seven possible diagnoses, 15 patients with metabolic neuropathy, five with motor neuron disease and six with chronic inflammatory demyelinating polyneuropathy were included. Nerve biopsy specimens were immunohistochemically examined for HIF‐1α and various cell markers. Distinct immunoreactivity (IR) was observed in nuclei of endoneurial cells in 54% (22/41) of vasculitic patients, while specimens from metabolic neuropathies showed less nuclear IR and the difference of mean density of HIF‐1α‐positive nuclei was significant. Two patients with possible vasculitis who showed HIF‐1α‐positive nuclei in endoneurium, were later confirmed to have vasculitis by skin biopsies. Most of the cells expressing HIF were demonstrated to be Schwann cells. There was a trend in the vasculitic patients with early phase nerve damage to display higher endoneurial HIF‐1α‐IR. HIF‐1α may be an immunohistochemical marker for vasculitic neuropathy, especially when the observed section contains no vasculitic lesions. 相似文献
16.
H Iwasaka T Kitano A Mizutani S Yoshitake S Hoashi T Noguchi K Taniguchi N Honda 《Masui. The Japanese journal of anesthesiology》1992,41(11):1719-1722
Thrombin-antithrombin III complex (TAT) and plasminogen activator inhibitor (PAI) were measured during liver resection surgery in 8 patients. TAT and PAI activities of patients under liver resection were compared with those of 11 patients under resection of esophageal carcinoma. TAT activity increased during liver resection (P < 0.001) and reached 14 times (P < 0.001) of its control value in the recovery room. PAI activity was very stable during operation, but increased to twice (P < 0.01) of its control value in the recovery room. TAT activity of patients after liver surgery in the recovery room was (P < 0.05) more than twice of that of patients after esophageal surgery. We conclude that hypercoagulable state occurred during liver resection to a greater degree compared with that observed with esophageal surgery, and that its cause might be liver resection itself. 相似文献
17.
We describe characteristic findings in a patient with Marchiafava-Bignami disease who was serially imaged with CT and MR. Involvement of the entire corpus callosum was visualized with both types of imaging. Following administration of gadolinium-DTPA, the lesion was clearly enhanced in the subacute stage.
Correspondence to: S. Otake 相似文献
18.
Hase I.; Oda Y.; Tanaka K.; Mizutani K.; Nakamoto T.; Asada A. 《British journal of anaesthesia》1997,79(6):740-743
We have examined the effect of fentanyl on the pharmacokinetics of
midazolam in patients undergoing orthopaedic surgery. Thirty patients were
allocated randomly to receive fentanyl 200 micrograms and midazolam 0.2 mg
kg-1 (fentanyl group, n = 15) or placebo and midazolam 0.2 mg kg-1 (placebo
group, n = 15) in a double-blind manner for induction of anaesthesia.
Anaesthesia was maintained with nitrous oxide and isoflurane. Systemic
clearance of midazolam was decreased by 30% (P = 0.002) and elimination
half-time was prolonged by 50% (P = 0.04) in the fentanyl group compared
with the placebo group. There were no differences in the distribution
half-time or volume of distribution at steady state between the two groups.
These findings indicate that elimination of midazolam was inhibited by
fentanyl during general anaesthesia.
相似文献
19.
Yamaji Yasuyoshi; Nakazato Yuichi; Oshima Naoki; Hayashi Matsuhiko; Saruta Takao 《Nephrology, dialysis, transplantation》2004,19(10):2592-2597
Background. Transferrin binds extracellular iron and protectstissues from iron-induced oxidative stress. The binding of ironand transferrin is pH dependent and conventional peritonealdialysis (PD) solutions have unphysiologically low pH values.Herein, we investigated whether conventional PD solution releasesiron from transferrin and if the released iron causes oxidativestress. Methods. Effects of PD solutions on iron binding to transferrinwere examined with purified human transferrin and transferrinin dialysates drained from PD patients. Oxidative stress inducedby iron released from transferrin was evaluated in terms ofthe formation of thiobarbituric acid reactive substance (TBARS)and protein carbonylation in the human red blood cell (RBC)membrane. The iron deposition in peritoneal tissue from PD patientswas evaluated by Perls' staining with diaminobenzidine intensification. Results. Low pH PD solution released iron from transferrin.This iron release occurred within 1 min. Iron release was notobserved in neutralized PD solution. Iron released from transferrinin low pH PD solution increased TBARS formation and proteincarbonylation in the human RBC membrane. Iron deposition, whichis prominent in the fibrotic area facing the peritoneal cavity,was observed in the peritoneum of PD patients. Conclusions. Iron released from transferrin in low pH PD solutioncan produce oxidative stress in the peritoneum of a PD patient.Neutralizing PD solution can avoid this problem. Iron depositionin the peritoneum may participate in the pathogenesis of peritonealfibrosis in PD patients. 相似文献
20.
H. Sone Y. Okuda M. Mizutani Y. Kawakami C. Bannai K. Yamashita 《Postgraduate medical journal》1995,71(840):613-616
The effects of nilvadipine on the peripheral circulation in the lower extremities using a duplex system of two-dimensional colour and pulse Doppler ultrasonography were studied in 32 patients with type 2 diabetes mellitus and mild essential hypertension. The patients (19 men and 13 women) were randomly divided into treatment and control groups. The anatomical cross-sectional area and blood flow index of the dorsal pedis artery were determined by colour and pulse Doppler ultrasonography before and 60 min after administration of 4 mg nilvadipine or placebo. Pulse rate and blood pressure were measured simultaneously. There were no significant changes in pulse rate or blood pressure after administration of either drug. Both cross-sectional areas (from 4.3 +/- 0.4 to 5.2 +/- 0.5 mm2, p < 0.05) and blood flow index (from 40.3 +/- 4.3 to 58.8 +/- 9.0, p < 0.05) were significantly increased in the treatment group, whereas there were no significant changes in either measurement in the control group. The findings showed that a single administration of nilvadipine increases blood flow in the dorsal pedis arteries of diabetic patients. 相似文献