Biomedical subjects

H Yamauchi

Publications and source records attributed to H Yamauchi.

At least 91 records · Page 5Linked to original sources

PubMed2000

[Causal models of achievement motive, goal orientation, intrinsic interest, and academic achievement in classroom].

This study investigated the effect of achievement motive on goal orientation, and that of goal orientation on intrinsic interest in learning and academic achievement, based on the model proposed by Elliot and Church (1997). A sample of 222 fifth and sixth grade students of an elementary school, and another of 307 seventh, eighth and ninth grade students of a junior high school participated in the study. The approach-avoidance framework of Elliot and Harackiewicz (1996) was used to classify goal orientations. With multiple-sample structural equation modeling, the paths in two causal models, one for each of the elementary and junior high school samples, were compared. A path was found from hope for success to mastery orientation, from both hope for success and fear of failure to performance-approach orientation, and from fear of failure to performance-avoidance orientation. Mastery and performance-approach orientations each had a positive effect on intrinsic interest in learning. For elementary school children, performance-approach orientation enhanced academic achievement, and for junior high school students, mastery orientation mainly facilitated it. Performance-avoidance orientation had a negative effect on both intrinsic interest and academic achievement.

Achievement↗

PubMed2000

Cerebral function after aortic surgery using retrograde cerebral perfusion: report of three cases.

INTRODUCTION: The neurological analysis undertaken on three cases of aortic aneurysm treated surgically using retrograde cerebral perfusion (RCP) are reported herein. This is the first detailed analysis of postoperative neurological studies in such cases. METHODS: The oxygenation state of cerebral Hb and cytochrome aa3 levels were monitored by near-infrared spectroscopy (NIR) during RCP. Postoperative neurological scoring, computed tomography (CT), magnetic resonance imaging (MRI), and monitoring of local cerebral blood flow (LCBF) quantatively by N-isopropyl-p-[123I] iodoamphetamine (IMP) single-photon emission computed tomography (SPECT) were performed for an extended follow-up period after surgery. RESULTS: The T2WI of MRI findings which consisted of many spotty high intensity areas in the striatum, cerebellum and hippocampus, may reflect the postoperative severe consciousness and mental disturbances (2-4 weeks). However, in all cases the neurological deficit gradually improved until they returned to their normal preoperative states. The improvement of LCBF correlated well with neurological recovery. CONCLUSION: The conditions of the conventional method of RCP must be improved to prevent transient severe consciousness and mental disturbances which occur after the operation in relationship with the appearance of the high intensity area on the MRI T2WI.

Adult↗

PubMed2000

[A trial of prospective payment system (DRGs/PPS) in Sendai National Hospital].

This study was undertaken to compare the difference between the total payment that was actually paid in accordance with the rules of DRGs/PPS, and the medical fee calculated by the present Japanese medical insurance system. From Nov. 1st '98 to Oct. 31st '99, the DRGs/PPS was applied to the 1,723(21.4%) out of 8,042 acute inpatients who were discharged after short-term stay. The total payment by the DRGs/PPS(yen 1,450,725,370) was smaller than the medical fee by the present Japanese insurance system(yen 1,504,686,240). In MDC (Major Diagnostic Category) 1(nervous system), 2(eye), 3(ear, nose, throat) and 4(circulatory system) the payment by the DRGs/PPS was greater than the fee calculated by the present medical insurance system. On the other hand, patients who belonged to the other 9 MDC groups paid smaller amounts by the DRGs/PPS. The major factors accounting for the difference(yen 53,960,870) between total payment DRGs/PPS and the fee by the present insurance system were period of hospital stay, treatment in the intensive care unit, complication, cancer chemotherapy, expensive surgical materials etc.

Diagnosis-Related Groups↗

PubMed2000

[Mitral valve regurgitation associated with severe pulmonary hypertension successfully treated with nitric oxide gas: report of a case].

A 61-year-old woman with mitral valve regurgitation and pulmonary hypertension, was referred to us for surgical repair. Preoperative left ventriculography showed Sellers IV mitral valve regurgitation and high pulmonary arterial pressure: 103/31 (57) mmHg. The mitral valve was replaced with a phi 27 mm SJM mechanical valve. The postoperative residual pulmonary hypertension was successfully treated with nitric oxide gas, decreased significantly pulmonary arterial pressure, and the postoperative course was uneventful. Based on our experience, we think that nitric oxide gas may prove effective for residual pulmonary hypertension after a cardiac operation.

Female↗

PubMed2000

Lymph-node staining with activated carbon CH40: a new method for axillary lymph-node dissection in breast cancer.

OBJECTIVE: To demonstrate the usefulness of activated carbon particles (CH40) as a vital staining dye for visualizing lymphatic vessels and lymph nodes in breast cancer. DESIGN: A retrospective evaluation. SETTING: Department of Surgery in Sendai National Hospital, Japan, a 716-bed teaching hospital. METHODS: To identify as many lymph nodes as possible in the axillary fat, by which we might decrease the possibility of the presence of undetected metastatic nodes, an emulsion of activated carbon particles (CH40) was injected into the centre of the mammary gland, close to the tumour site, 3 days before radical surgery. MAIN OUTCOME MEASURE: The number of lymph nodes found by the traditional method and by the CH40-injection method were recorded. RESULTS: After injection, the CH40 was readily adsorbed into regional lymphatics and streamed along with the lymph flow to blacken regional lymph nodes. The CH40-guided method increased the mean number of nodes per case found in the axilla from 8.4, by the traditional method, to 14.0 nodes per case. CONCLUSIONS: The use of the CH40 technique has two technical advantages; one is that it allows surgeons to locate the blackened lymph nodes at the time of surgery and the other is that it allows pathologists to look for the nodes in fatty tissue. Lymph-node dissection with the aid of activated carbon particles is inexpensive, easy to perform and enables the smallest lymph nodes to be easily recognized. CH40 is the technique of choice for the detection of axillary lymph nodes in cases where the number of lymph nodes detected by the traditional method is too small for accurate surgery. In conclusion, the present study demonstrates that CH40 could be an appropriate tool for more accurate staging of breast cancer axillary specimens.

Adult↗

PubMed2000

Quality of life in patients over 70 years of age after heart valve replacement.

BACKGROUND: Previous studies on valve replacement in patients over 70 years of age have been concerned with early and long-term outcome. Little is known, however, of the quality of life (QOL) of survivors following surgery. METHODS: Thirty-one consecutive patients, mean age 74.0+/-3.1 years, who underwent heart valve replacement were reviewed and questioned as to their physical and social activities before and after surgery and compared with 75 patients aged less than 70 years old who underwent similar procedures during the same time interval. QOL was measured by using the Rosser distress and disability scores. RESULTS: Hospital mortality in the elderly group was the same as in the younger group (9.7% vs 2.7%, p = 0.121). Median 5-year survival was 79% in the elderly group and 92% in the younger group (p = 0.068). Overall morbidity due to valve-related complications was 3.55%/patient-year in the elderly group and 2. 35%/patient-year in the younger group, and freedom from all valve-related complications at 5 years was 76%, and 83%, respectively (p = 0.202). There were significant improvements in the distress and disability scores postoperatively (mean interval: 32. 4+/-20.4 months). The QOL value rose from 0.960 to 0.981 in the elderly group (p = 0.0004), and from 0.975 to 0.984 in the younger group (p = 0.07), suggesting that the magnitude of improvement in the elderly group was superior to that in the younger group. CONCLUSIONS: Heart valve replacement in patients over the age of 70 years was associated with reasonable early and mid-term morbidity. We believe that significant improvements in the symptoms, functional status, and QOL of the patients can be expected.

Aged↗

PubMed2000

[Therapeutic bronchoscopy for stenotic lesions of central airway].

We retrospectively studied 26 patients with stenotic lesions of the central airway who had undergone bronchoscopic treatment. Thirteen of the patients had malignant tumors, and 13 had benign lesions (1 with post-tracheostomy difficulty in tube retrieval, 2 with bronchial obstruction due to granulation after bronchoplasty, 1 with bronchial stenosis due to granulation after pulmonary lobectomy, 7 with endobronchial foreign bodies, and 2 with hemoptysis). The patients ranged from 5 to 88 years of age with an average of 59.7 years. As a rule, bronchoscopic treatment was performed with endotracheal intubation up to 1993, and with laryngeal mask placement in 1994 and thereafter. Of the 26 eligible patients, 24 (92%) experienced good or excellent outcomes. Emergency bronchoscopy may be useful in treating a variety of emergency airway conditions. Use of a laryngeal mask may benefit emergency patients, including infants and children requiring a secure airway without complications.

Adult↗

PubMed2000

Evaluation of body fluid status after cardiac surgery using bioelectrical impedance analysis.

BACKGROUND: In the assessment of fluid status after cardiac surgery, we applied bioelectrical impedance analysis (BIA) to measure the total body water (TBW), extracellular fluid (ECF), and intracellular fluid (ICF), and evaluated its validity. METHODS: Thirty patients who underwent cardiopulmonary bypass (CPB group) and 19 surgical patients not receiving CPB (non-CPB group). RESULTS: The change of BIA values (deltaTBW, deltaECF, deltaICF), body weight and cumulative fluid balance were determined for 120 postoperative hours, and the relationship between BIA values and body weight and fluid balance were evaluated. Postoperative changes in BIA values in the CPB group were compared with those in the non-CPB group. Finally the ECF/ICF ratio and hemodynamic parameters were compared. deltaTBW and deltaECF correlated with changes in body weight and fluid balance, respectively. Especially there was a high correlation in each case although large deviations in the slope of the regression lines were observed. TBW and ECF increased from immediately after operation up to 96 hours (the maximum value was at day 2). On the other hand, ICF decreased from 48 to 72 hours after operation. There were significant high ECF/ICF in the CPB group compared with the non-CPB group from 12 to 72 postoperative hours. We found that ECF/ICF correlated inversely with mean blood pressure, mixed venous oxygen saturation and colloid osmotic pressure, and positively with central venous pressure and pulmonary artery wedge pressure. CONCLUSIONS: It was considered that BIA was useful for evaluating the relative changes in TBW and fluid distribution, and ECF/ICF might be a new parameter for abnormal water metabolism after cardiac surgery.

Aged↗

PubMed2000

Clinicopathologic prognostic factors in patients with Borrmann type 4 gastric cancer: univariate and multivariate analyses.

BACKGROUND: Advanced gastric cancer is classified into four Borrmann types, types 1 to 4. Type 4 is a relatively undifferentiated carcinoma with little or no gland-forming capability. Despite recent advances in the diagnosis and surgical management of gastric cancer, most tumors of Borrmann type 4 are not detected at an early stage and the prognosis remains poor; the five-year survival rate after gastric resection ranges from 10 to 20 percent. We evaluated the affects of several clinicopathologic variables on the 5-year survival rate after resection of Borrmann type 4 gastric cancer. METHODS: Data on clinical characteristics were obtained from the records of patients who underwent gastric resection between 1985 and 1995 at the Department of Surgery, Sendai National Hospital, and follow-up data were obtained from our tumor registry. Pathologic characteristics were determined from a detailed review of all available histopathologic slides. The relationship between clinicopathologic variables and 5-year survival rate was estimated by the Kaplan-Meier survival curve and the logrank test. Multivariate Cox's proportional hazards regression analysis was then performed to determine which variables were independent prognostic factors. RESULTS: Eighty-seven patients with Borrmann type 4 gastric cancer underwent a resection during the study period at our hospital. The overall 5-year survival rate was 14.8%. The relationship between clinicopathologic variables and 5-year survival rate was determined by constructing a Kaplan-Meier survival curve. Tumor location (upper, middle and distal vs whole stomach, p=0.0214), lymph node metastasis, capillary microinvasion, and peritonitis carcinomatosa (absent vs present, p<0.05) significantly influenced survival. When multivariate analysis using Cox's proportional hazards regression of 5-year survival was performed, capillary microinvasion, peritonitis carcinomatosa (absent vs present) and tumor location (distal vs whole stomach) emerged as the statistically significant independent prognostic factors associated with long-term survival. CONCLUSION: Capillary microinvasion and the presence or absence of peritonitis carcinomatosa are more powerful predictors of 5-year survival than is lymph node metastasis. Patients with gastric cancer of the whole stomach have a poorer prognosis than do those with carcinoma in the antrum of the stomach.

Adult↗

PubMed2000

Quantitative determination of urinary 8-hydroxydeoxyguanosine (8-OH-dg) by using ELISA.

In order to establish a quantitative assay for 8-OHdG concentrations in urine, we examined the precision of a test for the recovery of 8-OHdG in urine by using an ELISA method. The coefficient of variation (CV) for assay with incubation in water or air ranged between 7.0% and 8.4% and between 19.2% and 30.6%, respectively. The data by using incubation in water gave higher accuracy than those in air. The recovery rates of 8-OHdG in urine sample ranged from 95 - 114%. Our results indicated that the excellent sensitivity of this ELISA kit by using incubation in water makes its use possible for the determination in urine with a good reproducibility and recovery of 8-OHdG-spiked samples.

8-Hydroxy-2'-Deoxyguanosine↗

PubMed1999

Brain arteriolosclerosis and hemodynamic disturbance may induce leukoaraiosis.

OBJECTIVE: To investigate whether internal carotid artery (ICA) occlusive disease-induced hemodynamic disturbance is associated with extensive white matter high-intensity lesions (WMLs) on T2-weighted MR images in the hemisphere with lacunar infarct in the basal ganglia. BACKGROUND: Hemodynamic disturbance in the brain with arteriolosclerosis may be one of the mechanisms by which ischemic injury induces extensive WMLs. METHODS: The authors used MRI and PET to study 21 patients with unilateral ICA occlusion or stenosis and lacunar infarct in the bilateral basal ganglia. In hemispheres with ICA disease, the association of WMLs with the mean hemispheric values of oxygen extraction fraction (OEF)-an index of hemodynamic compromise-measured with the 15O-labeled gas steady-state technique was analyzed. Twenty-five patients with ICA occlusive disease without lacunar infarct were studied as control subjects. RESULTS: In the hemispheres with ICA disease, patients with lacunar infarct had a significantly greater severity of WMLs than control subjects, although the mean hemispheric values of the OEF showed no significant difference. The severity of WMLs correlated significantly with the mean hemispheric values of the OEF in patients with lacunar infarct, but not in control subjects. Multivariate analysis revealed that lacunar infarcts and increased OEF were independent predictors of extensive WMLs, with lacunar infarcts the most heavily weighted factor. CONCLUSION: Internal carotid artery occlusive disease-induced hemodynamic disturbance is associated with extensive WMLs in hemispheres with lacunar infarct. Hemodynamic disturbance may contribute to the development of extensive WMLs, although brain arteriolosclerosis may be a major contributing factor.

Aged↗

PubMed1999

The effect of sequential lesioning in the basal forebrain on cerebral cortical glucose metabolism in rats. An animal positron emission tomography study.

We studied the effect of the cortical projection from the basal forebrain on the cerebral cortical metabolism using positron emission tomography (PET) with [(18)F] fluorodeoxyglucose. Unilateral damage of the nucleus basalis magnocellularis (NBM) did not cause a permanent reduction of cortical metabolism: recovery was observed 4 weeks after the operation. Destruction of the contralateral side after recovery from unilateral damage produced persistent bilateral suppression of glucose metabolism, with partial recovery. We speculate that recovery from the unilateral NBM lesions is partly ascribable to the cholinergic projection from the contralateral NBM, and partly due to non-cholinergic systems, and conclude that bilateral damage might be responsible for persistent cortical glucose metabolism suppression.

Animals↗

PubMed1999

Cerebral glucose metabolism in unilateral entorhinal cortex-lesioned rats: an animal PET study.

To evaluate the effect of entorhinal cortical lesion on cerebral cortical function, we studied cerebral glucose utilization (CMRGlc) using a high resolution PET scanner after quinolinic acid lesion of the unilateral entorhinal cortex in rats. [18F]Fluorodeoxyglucose PET was performed at 4 days and 4 weeks after surgery, and CMRGlc in the bilateral frontal, parietal and temporal regions were analyzed. At 4 days, the entorhinal lesion induced a 12-15% decrease in CMRGlc of frontal, parietal and temporal regions ipsilateral to the lesion. The hypometabolism continued at 4 weeks in the temporal region. These findings suggest that entorhinal lesion induces cerebral cortical hypometabolism, which implies a pathogenetic role of entorhinal area on the cortical hypometabolism in Alzheimer's disease.

Analysis of Variance↗

PubMed1999

IL-18 up-regulates perforin-mediated NK activity without increasing perforin messenger RNA expression by binding to constitutively expressed IL-18 receptor.

IL-18 is a powerful inducer of IFN-gamma production, particularly in collaboration with IL-12. IL-18, like IL-12, also augments NK activity. Here we investigated the molecular mechanism underlying the up-regulation of killing activity of NK cells by IL-18. IL-18, like IL-12, dose dependently enhanced NK activity of splenocytes. This action was further enhanced by costimulation with IL-12. Treatment with anti-IL-2R Ab did not affect IL-18- and/or IL-12-augmented NK activity, and splenocytes from IFN-gamma-deficient mice showed enhanced NK activity following stimulation with IL-12 and/or IL-18. Splenocytes from the mice deficient in both IL-12 and IL-18 normally responded to IL-18 and/or IL-12 with facilitated NK activity, suggesting that functional NK cells develop in the absence of IL-12 and IL-18. IL-18R, as well as IL-12R mRNA, was constitutively expressed in splenocytes from SCID mice, which lack T cells and B cells but have intact NK cells, and in those from IL-12 and IL-18 double knockout mice. NK cells isolated from SCID splenocytes expressed IL-18R on their surface. IL-18, in contrast to IL-12, did not enhance mRNA expression of perforin, a key molecule for exocytosis-mediated cytotoxicity. However, pretreatment with concanamycin A completely inhibited this IL-18- and/or IL-12-augmented NK activity. Furthermore, IL-18, like IL-12, failed to enhance NK activity of splenocytes from perforin-deficient mice. These data suggested that NK cells develop and express IL-12R and IL-18R in the absence of IL-12 or IL-18, and that both IL-18 and IL-12 directly and independently augment perforin-mediated cytotoxic activity of NK cells.

Animals↗

PubMed1999

Transient neural activity in the medial superior frontal gyrus and precuneus time locked with attention shift between object features.

To investigate the contribution of the superior frontal gyrus and precuneus to the cognitive process of attention set shift, we examined the correlation between change in neural activity in these areas and the timing of attention set shift using event-related functional magnetic resonance imaging. Seven subjects underwent a card-sorting task in which they matched a test card to one of two target cards according to color or shape. The subjects had to determine the correct category based only on feedback and shift the sorting principle when the feedback changed from "correct" to "incorrect." Transient increase of neural activity time locked with attention shift phases was detected in the medial superior frontal gyrus (the rostral part of the supplementary motor area) and precuneus. During the control task, in which the feedback and the motor responses were preserved without any attention shift, this type of change in neural activity was not observed. Our findings indicate that increase in neural activity in these brain areas may be closely related to attention set shift between object features and suggest that these areas may play a role in the shifting of cognitive sets.

Adult↗

PubMed1999

The prognostic significance of lymph node metastasis and intrapancreatic perineural invasion in pancreatic cancer after curative resection.

To investigate the prognostic factors of pancreatic cancer, a retrospective analysis of 193 patients who underwent curative resection was conducted. Of the 193 patients, 38 (20%) survived for more than 5 years, the 5-year survival rates for stages I, II, II, and IV disease being 41%, 17%, 11%, and 6%, respectively. According to a multivariate analysis, lymph node metastasis, intrapancreatic perineural invasion, and portal vein invasion were significant prognostic factors. Subsequently, a subgroup analysis concerning nodal metastasis and intrapancreatic perineural invasion was performed in 126 patients with records of these histological findings. In the group of patients without nodal metastasis, the 5-year survival rate for those without perineural invasion was 75%, whereas that for those with perineural invasion was 29%, the difference in survival of these subgroups being significant (P < 0.02). In the group of patients with nodal metastasis, the 5-year survival rate for those without perineural invasion was 17%, while that for those with perineural invasion was 10%. The most favorable 5-year survival of 89% was observed in the subgroup of patients with stage I disease without perineural invasion. Thus, pancreatic adenocarcinoma categorized by the combination of these independent types of biological behavior showed 5-year survival rates ranging from very high to low, indicating that these two factors play an important role in the prognosis of this disease.

Adenocarcinoma↗

PubMed1999

An aberrant left subclavian artery aneurysm with right aortic arch: report of a case.

The case of a 41-year-old man who developed an aneurysm in his aberrant left subclavian artery is described. The patient had a right aortic arch. After a successful aortosubclavian artery bypass, symptoms due to brain ischemia disappeared. This is a very rare disease that is sometimes associated with an aortic anomaly, therefore the optimal therapeutic procedure need to be carefully selected, including the operative indications and approach.

Adult↗

PubMed1999

Pancreatic division by electrocautery in pancreatoduodenectomy.

To assess whether electrocautery is appropriate for cutting the pancreas in pancreatoduodenectomy, we compared leakage of the pancreatojejunostomy (PJ-stomy) in patients who underwent pancreatic division by electrocautery and with a conventional scalpel, in a retrospective study. Eighty-four patients with invaginating end-to-end PJ-stomies (performed in the period 1986-1996) were enrolled in this study; 34 patients underwent pancreatic division with a conventional scalpel (group A) and 50 by electrocautery (group B). Of the 84 patients, 12 (14%) had leakage from the PJ-stomies. In relation to consistency of the pancreatic parenchyma, the incidence of leakage in patients with hard pancreas (1/28; 3.6%) was significantly lower than that in patients with soft or moderate pancreas consistency (11/56; 20%) (P < 0.05). Nine patients (27%) in group A and 3 (6%) in group B presented with leakage. The incidence of leakage was significantly lower in group B than in group A (P < 0. 05). Even when patients with hard pancreas were excluded, the incidence of leakage was significantly lower in group B (3/34; 9%) than in group A (8/22; 36%) (P < 0.05). These results suggest that pancreatic division by electrocautery can reduce the incidence of leakage from the pancreatojejunostomy and make pancreatoduodenectomy a safer procedure.

Adult↗