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121.
Objectives: We investigated the ability of diltiazem to prevent myocardial injury by assessing heart function and intracellular calcium concentrations before and after ischemia-reperfusion. Method: Isolated rat hearts underwent cardioplegia using the Langendorff perfusion model and were subjected to normothermic global ischemia for 60 minutes. The recovery rates for the heart function (heart rate, coronary flow, left ventricular systolic pressure) after reperfusion were monitored, and the intracellular Ca concentration was measured during ischemia and during the following reperfusion. Experimental groups were divided into three groups according to the diltiazem concentration used in the cardioplegic solution (potassium 20 mmol/l in Ringer's solution): (1) Group A: diltiazem 2.5 mg/l; (2) Group B: diltiazem 5 mg/l; and (3) Group C: no diltiazem. Results: Intracellular calcium concentration increased in all 3 groups during ischemia, but was significantly lower in Group B compared to either Group A or Group C. The heart function was significantly higher for Group A than for Group B or Group C. The hearts in Group B displayed markedly poor recovery in contractility and in heart rate. Conclusions: Generally, a decrease in intracellular Ca concentration improves the heart function during ischemia and after reperfusion. However, this study showed that some increase in intracellular Ca at the beginning of reperfusion assisted the contractility of rat heart.  相似文献   
122.
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage.  相似文献   
123.
A 39-year-old woman with multiple sclerosis (MS) at exacerbation stage underwent dilatation and curettage. MS is characterized by chronic inflammation, demyelination, and gliosis in the central nervous system. Surgical stress often induces exacerbation of MS symptoms. Therefore, deep anesthesia is required for anesthetic management in cases of MS. We monitored electroencephalograph (EEG), spectral edge frequency 90 (SEF 90), spectral median frequency (SMF) and delta-amplitude for depth of anesthesia using pEEG (Dr?ger, Germany). In this case, anesthesia was induced with sevoflurane and gradually increased to 5% in oxygen 4 l.min-1 and maintained with sevoflurane 2-3% in 2 nitrous oxide l.min-1 and 2 l.min-1 oxygen. Surgery was completed and no spike wave was observed by pEEG monitoring during surgery. In conclusion, sevoflurane anesthesia was useful for a patient with MS during exacerbation stage.  相似文献   
124.
Alagille syndrome (AGS) is an autosomal dominant genetic disorder characterized by chronic cholestasis, congenital heart disease, peculiar facies, butterfly-like vertebrae, and posterior embryotoxon. Liver dysfunction is the common presentation of AGS, and liver transplantation may be indicated. This study examines the outcome of living-related liver transplantation (LRLT) for AGS. Twenty patients with AGS (median age 5.0 years, range 0.6-12.9) underwent LRLT at Kyoto University Hospital between June 1990 and February 2002. Five potential donors were excluded because of paucity of intrahepatic bile ducts diagnosed by preoperative liver biopsy and one because of a hepatic vascular anomaly. The overall 5-year patient survival was 80.4%. Three patients died as the result of the following: complications related to surgery, heart failure caused by progressive pulmonary artery stenosis, and a graft with unsuspected bile duct paucity. Liver dysfunction was improved in all successful cases, and catch-up growth occurred in 90% of patients. LRLT is an efficacious treatment modality for AGS if donors are selected by cautious evaluation to rule out unsuspected bile duct paucity.  相似文献   
125.
We investigated mRNA expressions of interleukin 10 (IL-10) during fracture healing for wound age determination. Macroscopically, calluses were formed at 144 h post-injury, and thickening of the fracture edge was observed at 240 h post-injury. Slight infiltration of neutrophils and macrophages was detected at 3 h post-injury, and moderate infiltration of T and B lymphocytes was detected at 72 h post-injury. In addition, osteoblasts proliferated at 24 h post-injury. IL-10 mRNA increased immediately after the intervention and peaked at 24 h, and the expressions were detected in osteocytes before and after injury, and in osteoblasts at 3 h post-injury. Although the intensity was stable in osteocytes, that in osteoblasts was strongest at 24 h post-injury. Among inflammatory cells, the expressions were exclusively detected in macrophages. These results indicated that examinations of macroscopic and microscopic changes in fracture edges, and mRNA expressions of IL-10, would be informative for fracture healing and dating.  相似文献   
126.
PURPOSE: To analyze the influence of matrix and echo time (TE) of three-dimensional time-of-flight (3D TOF) magnetic resonance angiography (MRA) on the depiction of residual flow in aneurysms embolized with platinum coils at 1.5T and 3T. MATERIALS AND METHODS: A simulated intracranial aneurysm of the vascular phantom was loosely packed to maintain the patency of some residual aneurysmal lumen with platinum coils and connected to an electromagnetic flow pump with pulsatile flow. MRAs were obtained altering the matrix and TE of 3D TOF sequences at 1.5T and 3T. RESULTS: The increased spatial resolution and the shorter TE offered better image quality at 3T. For the depiction of an aneurysm remnant, the high-spatial-resolution 3T MRA (matrix size of 384 x 224 and 512 x 256) with a short TE of < or =3.3 msec were superior to the 1.5T MRA obtained with any sequences. CONCLUSION: 3T MRA is superior to 1.5T MRA for the assessment of aneurysms embolized with platinum coils; the combination of the 512 x 256 matrix and short TE (3.3 msec or less) seems feasible at 3T.  相似文献   
127.
INTRODUCTION: Few studies have reported the response of high-molecular-weight (HMW) adiponectin to acute aerobic exercise. PURPOSE: The purpose of this study was to investigate the influence of acute aerobic exercise on HMW adiponectin in healthy men. METHODS: Eight healthy men (age, 24.9 +/- 1.8 yr; BMI, 21.9 +/- 0.5 kg x m) participated in this study. They performed two trials. Trial 1 [exercise trial (EX)] consisted of 60-min stationary cycle exercise (50% peak oxygen uptake) followed by 30-min rest. Trial 2 [control trial (CON)] was 90-min rest. Blood samples were drawn to assess hormones (catecholamine and insulin), metabolites (free fatty acid [FFA], glycerol, and glucose), and total and HMW adiponectin concentration. RESULTS: There were significant trial x group interactions in serum FFA and glycerol concentrations (P < 0.05). Serum FFA and glycerol concentrations were higher in EX than in CON (P < 0.05). There were significant trial x group interactions in plasma insulin and glucose concentration (P < 0.05). Plasma insulin and glucose concentrations were lower in EX than in CON (P < 0.05). Total adiponectin, HMW adiponectin concentration, and the ratio of HMW to total adiponectin concentration, however, were unchanged during aerobic exercise and postexercise. Also, those changes did not differ between EX and CON. CONCLUSION: Our results indicate that total adiponectin and HMW adiponectin concentrations are not regulated by the change of hormones or metabolites during acute moderate-intensity aerobic exercise and postexercise in healthy young men.  相似文献   
128.
BACKGROUND: Apoptosis in isolated islets has been implicated in primary nonfunction or early graft failure after islet transplantation. Recently, pancreas preservation by the 2-layer method (TLM) before islet isolation has been proved to improve the islet yield, quality, and transplant results not only in experimental models, but also in clinical settings. We examined the influence of TLM on apoptosis of isolated islets. METHOD: Rat islets freshly isolated and after pancreas preservation by TLM or conventional cold storage in University of Wisconsin solution (UW) were examined and compared. Islet apoptosis was assessed by TUNEL and annexin V assays. The apoptosis pathways involved were investigated by measurement of caspase 3, 8, and 9 activities and by immunoblotting for total and phosphorylated c-Jun NH2-terminal kinase (JNK) and p38. RESULTS: Islet apoptosis in the UW group was significantly increased compared with the fresh and TLM groups. Both caspase 3 and 9 activities in the UW group were higher than in the fresh and TLM groups with an approximate increase of 2- to 3-fold. On the other hand, there was no significant difference in caspase 8 activity among these 3 groups. JNKs were strongly activated both in the TLM and UW groups; although they were not activated in the fresh group, p38 was activated to almost the same levels in these 3 groups. CONCLUSIONS: Pancreas preservation by TLM before islet isolation protects isolated islets against apoptosis mainly through the mitochondrial pathway. Pancreas storage before islet isolation even with TLM triggers activation of JNKs in isolated islets.  相似文献   
129.
We tested the hypothesis that a silicone-based wire-reinforced tracheal tube with a hemispherical bevel is superior to a polyvinyl chloride (PVC)-based precurved tube with a conventional diagonal bevel for nasotracheal intubation. Eighty anesthetized paralyzed adults (ASA physical status I-II) requiring nasotracheal intubation for tonsillectomy were randomly allocated into two equal-sized groups for airway management with the silicone tracheal tube or PVC tracheal tube. Intubation was subdivided into three phases: 1). passage through the nose into the pharynx, 2). laryngoscope-guided passage into the glottic inlet, and 3). laryngoscope-guided passage into the trachea. A specific sequence of airway maneuvers was followed at each stage if it was unsuccessful. The number of attempts and intubation time were documented by an unblinded observer. The frequency of epistaxis and postoperative nasal complications was documented by blinded observers. There were no intubation failures. The number of attempts at pharyngeal (47 versus 56; P = 0.04) and tracheal (43 versus 55; P = 0.005) placement was smaller for the silicone tracheal tube, but the number of attempts at glottic placement was more (72 versus 49; P < 0.0001). Intubation time was similar. The frequency (32% versus 80%; P < 0.0001) and severity of epistaxis were less for the silicone tracheal tube. The total number of postoperative nasal symptoms was smaller for the silicone tracheal tube (10 versus 21; P < 0.05). We conclude that the pharyngeal and tracheal placement phases of nasotracheal intubation require fewer attempts with the silicone tracheal tube than the PVC tracheal tube but that the glottic placement phase requires more attempts. Nasal morbidity is less common with the silicone tracheal tube. IMPLICATIONS: The pharyngeal and tracheal placement phases of nasotracheal intubation require fewer attempts with a silicone-based wire-reinforced tracheal tube with a hemispherical bevel than with a polyvinyl chloride-based precurved tracheal tube with a conventional diagonal bevel, but the glottic placement phase requires more attempts. Nasal morbidity is less common with the silicone tracheal tube.  相似文献   
130.
In our previous study, ketamine administration was found to inhibit hypotension, metabolic acidosis, and cytokine responses in endotoxemia. However, only a few studies have indicated whether ketamine has the dose-related beneficial effects after endotoxin injection. Our objective was to clarify the dose-related effects of ketamine on mortality and cytokine responses to endotoxemia in rats. Sixty-five rats were divided at random among five equal groups: Group C was given saline alone. Group E was given endotoxin alone (Escherichia coli endotoxin; 10 mg/kg, IV). Group L received a a low dose of ketamine (5 mg.kg(-1).h(-1), IV), Group M a medium dose of ketamine (10 mg.kg(-1).h(-1), IV), and Group H a high dose of ketamine (20 mg.kg(-1).h(-1), IV), all exposure to endotoxin. After endotoxin injection, hemodynamics, acid-base status, mortality rate, and plasma concentrations of tumor necrosis factor alpha and interleukin 6 were assessed for each of the five groups. Endotoxin injection produced progressive hypotension, metabolic acidosis, and a large increase in plasma cytokine concentrations. Mortality rates 8 h after endotoxin injection were 0% for group C, 92% for group E, 48% for group L, 0% for group M, and 32% for group H. Ketamine administration thus clearly had a beneficial effect on mortality rates, with that for group M lower than for groups L and H (P < 0.05). The cytokine responses to endotoxin were somewhat suppressed in group M but not in group L. Ketamine administration dose-independently inhibited hypotension, metabolic acidosis, and cytokine responses in rats injected with endotoxin.  相似文献   
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