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Biomedical subjects

S Kawamura

Publications and source records attributed to S Kawamura.

At least 55 records · Page 3Linked to original sources
PubMed2000

Massive bleeding from multiple jejunal diverticula associated with an angiodysplasia: report of a case.

We report herein the case of a 70-year-old woman who presented with massive bleeding from multiple jejunal diverticula. She was initially admitted to our hospital with massive melena. An upper gastrointestinal endoscopic examination revealed no bleeding site. Colonoscopy revealed clotted and red blood throughout the colon, and a small diverticulum in the ascending colon which was thought to be the source of bleeding. Following admission, she was treated conservatively at first, but melena continued and the anemia did not improve despite blood transfusions. A laparotomy was performed and multiple jejunal diverticula, distributed from 10 to 40 cm distal to the ligament of Treitz, were found. A segment of the jejunum containing all diverticula was resected. The most distal diverticulum contained a clot of blood, but no ulceration was observed. A histological examination revealed many dilated blood vessels in the mucosa and submucosa of this diverticulum, which were compatible with the findings of angiodysplasia. Based on these findings, we believe that angiodysplasia was the cause of bleeding from the jejunal diverticula in this case.

Aged↗
PubMed2000

Cerebral blood flow and oxygen metabolism during mild hypothermia in patients with subarachnoid haemorrhage.

Cerebral blood flow and O2 metabolism during hypothermia (33-34 degrees C) was evaluated in 5 patients with aneurysmal subarachnoid haemorrhage by positron emission tomography (PET). Their preoperative clinical condition was WFNS scale IV or V. The patients received surface cooling postoperatively, and were maintained in a hypothermic state during transfer for radiological examination. Positron emission tomography revealed a decrease in cerebral blood flow and O2 metabolic rate. Cerebral blood flow was 34.8+/-15.1 ml/100 ml/min and the O2 metabolic rate was 1.85+/-0.61 ml/100 ml/min in areas of the middle cerebral artery ipsilateral to the ruptured aneurysms, whereas these values were 30.8+/-7.1 and 2.21+/-0.45 ml/100 ml/min, respectively, on the contralateral side. This represents a decrease of 37+/-27% compared to normal cerebral blood flow and 52+/-16% compared to normal O2 metabolic rate (p < 0.02) in the ipsilateral areas, and decreases of 44+/-13% and 43+/-12%, respectively, on the contralateral side. The present results reflected the luxury perfusion state in almost all cases and provide the first PET evidence of decreased cerebral blood flow and metabolic rate of O2 during hypothermia in humans.

Adult↗
PubMed2000

Effect of caspase inhibitors on myocardial infarct size and myocyte DNA fragmentation in the ischemia-reperfused rat heart.

OBJECTIVE: Caspase family proteases are recognized as key mediators of apoptosis. However, the role of caspases in the ischemia-reperfused heart remains uncertain. We evaluated the effect of caspase inhibitors on myocardial infarct size and the myocyte DNA fragmentation in the ischemia-reperfused rat hearts. METHODS: Three groups of Sprague-Dawley rats (n = 7, each) were subjected to 30 min of ischemia followed by 6 h of reperfusion. One of the following drugs: (1) YVAD-aldehyde, a caspase-1-like protease inhibitor (3.5 mg/kg; YVAD), (2) DEVD-aldehyde, a caspase-3-like protease inhibitor (3.5 mg/kg, DEVD), (3) vehicle (140 microliters/kg) was administered intravenously 5 min prior to the ischemia in each group. Myocardial infarct size was defined by triphenyltetrazolium chloride (TTC) staining. Immunohistochemical staining by in situ nick end labeling (TUNEL) of cardiomyocytes and DNA electrophoresis were used for detecting DNA fragmentation. Ultrastructural analysis was done by electron microscopy. The caspase activity was measured in the myocardium of both groups. RESULTS: The percentage of TUNEL-positive myocyte nuclei (%AP) was quantified by microscopy. A ladder pattern was detected by electrophoresis of DNA from the risk area and TUNEL-positive myocytes were seen in the risk area. The %AP was significantly reduced from 20 +/- 1% to 12 +/- 3% by YVAD and to 10 +/- 3% by DEVD (both P < 0.01). However, caspase inhibitors did not significantly change the infarct size. Electronmicrograph showed similar salcolemmal and mitochondrial damage in both group. The caspase activity was blocked by DEVD at 4 h after reperfusion. CONCLUSION: Myocyte DNA fragmentation and caspase activation was inhibited by caspase inhibitors without reduction of the infarct size in ischemia-reperfused rat hearts.

Analysis of Variance↗
PubMed2000

Successful transplantation of a cadaveric kidney with post-infectious glomerulonephritis.

This report describes a successful renal Tx in a patient with chronic renal failure, caused by dysplastic kidneys, who received a cadaveric kidney with post-infectious glomerulonephritis. Sequential renal biopsies were performed at 12 h before Tx, and at 1 h and on days 8 and 58 post-Tx. Post-operative hematuria disappeared on day 9 and proteinuria on day 13. Normal graft function was observed within 1 month, with histologic resolution. Our study suggests that while the donor kidney facilitates deposition of certain immune reactants, this is a host (environmental) problem and when transplanted into a new host (new environment), the problem is no longer sustained.

Adolescent↗
PubMed2000

Mild hypothermia mitigates post-ischemic neuronal death following focal cerebral ischemia in rat brain: immunohistochemical study of Fas, caspase-3 and TUNEL.

Mild hypothermia is considered to have a protective effect during ischemic neuronal cell death. The present study provides experimental evidence for this beneficial role of mild hypothermia using reversible middle cerebral artery occlusion (MCAo) in a Sprague-Dawley (SD) rat model. MCAo was induced in rats for 1 h followed by reperfusion at different periods. Hematoxylin-eosin (HE) staining in normothermic (NT) 37 degrees C and hypothermic (HT) 33 degrees C groups of rats confirmed cerebral infarcts. The mean per cent infarct area was significantly reduced in the HT group of rats. Immunohistochemical analysis was done using anti-Fas and caspase-3 antibodies. The immunohistochemical expression of Fas and caspase-3 was demonstrable as early as 5 h after reperfusion, but the expression pattern maximized at 24 h after reperfusion. The expression of Fas and caspase-3 proteins showed a clear decrease in the HT group over the NT group. In situ detection of DNA fragmentation was done using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling method (TUNEL). TUNEL-positive cells were first observed at 5h after reperfusion and progressively increased by 24h. A higher number of TUNEL-positive cells was found in the NT group, but they were significantly decreased in the HT group. Further, DNA fragmentation was confirmed by size fractionation in agarose gel. These findings demonstrate a positive relation between the expression of Fas, caspase-3 and TUNEL-positive cells.

Animals↗
PubMed2000

The survey of sleeping time of junior high school students: a study on the sleep questionnaire.

We investigated the questionnaire study on sleep of junior high school students to estimate the effect of excessive study hours on their sleep time in 1998. A total of 501 students answered the questionnaire. It was noted that most of the students sleep for 6-8 h on weekdays. The majority of the students of the junior high school felt that their sleep is insufficient on weekdays.

Adolescent↗
PubMed2000

Echocardiographic evaluation of the ductal morphology in patients with refractoriness to lipo-prostaglandin E1 therapy.

BACKGROUND: Lipo-prostaglandin (PG)E1 is effective at lower doses and has fewer side effects than PGE1-cyclodextrin (CD). Previous studies, however, have suggested that some patients show refractoriness to lipo-PGE1 in the course of treatment. The present paper examines: (i) whether such cases can be predicted by examining the ductal morphology before and 24 h after the start of lipo-PGE1 infusion; and (ii) whether PGE1-CD dilates the ductus arteriosus in patients with refractoriness to lipo-PGE1. METHODS: The ductal morphology was evaluated with two echo indices, such as minimal and minimal plus maximal intraluminal diameters of the ductus. Two-dimensional echocardiography was performed in 24 patients with ductus-dependent congenital heart disease. The two echo indices were measured before and 24 h after lipo-PGE1 infusion and also at least twice per week until surgery. RESULTS: In 19 of 24 patients, ductal patency was maintained until surgical treatment (group A). The remaining five patients (21%) showed ductal closure during the course of the lipo-PGE1 therapy (group B). There were no significant differences between the two groups, in either the maximal or minimal diameters, which were examined before and 24 h after treatment. In the five patients of group B, lipo-PGE1 was replaced with a relatively high dosage of PGE1-CD (50-100 ng/kg per min), resulting in good ductal patency until surgery. CONCLUSIONS: Patients with refractoriness to lipo-PGE1 therapy could not be predicted from initial intraluminal diameters of the ductus using echocardiography. Therefore, serial echocardiographic examinations are important to detect early findings of ductal closure. In addition, PGE1-CD is still useful as back-up therapy in such patients.

Alprostadil↗
PubMed2000

Peripheral blood extrathymic CD4(+)CD8(+) T cells with high cytotoxic activity are from the same lineage as CD4(+)CD8(-) T cells in cynomolgus monkeys.

We have previously reported that CD4/CD8 double-positive (DP) T cells with the resting memory phenotype are present in the periphery of healthy cynomolgus monkeys. In the present study, we performed functional studies on the T cells. The expression of CD4 and CD8 on DP, CD4 single-positive (SP) or CD8 SP T cells was stable in cultures with either mitogen or anti-CD3 antibody stimulation. In spite of lacking CD28 expression, DP T cells showed similar proliferative ability and apoptosis sensitivity to CD4 SP and CD8 SP T cells. DP T cells showed both helper and cytotoxic activities. Although the helper activity of DP T cells was lower than that of CD4 SP T cells, cytotoxic activity was comparable to that of CD8 SP T cells. Fresh DP T cells killed target cells mainly by the perforin-granzyme pathway. In addition, fresh DP T cells expressed a high level of mRNA for IFN-gamma and produced a high level of IFN-gamma when they were activated by anti-CD3 antibody ligation. On the other hand, several expanded DP T cell clones shared TCR V(beta) with expanded CD4 SP T cell clones, strongly suggesting that those two corresponding clones with DP and CD4 SP phenotypes might be derived from the same ancestor T cell. These results showed that the DP T cells are a novel T cell subset with functions overlapping with those of CD4 SP and CD8 SP T cells, and that they might play protective and regulatory roles in secondary immune response in cynomolgus monkeys.

Animals↗
PubMed2000

Purification of bovine urinary beta2-microglobulin and its biochemical characteristics.

In this study, bovine beta2-m was purified from urine by ion-exchange chromatography and gel chromatography, and the characteristics were compared with those of colostral beta2-m by the immunological reactivity, isoelectric points, peptide map, and amino acid sequence. The characteristics of purified urinary beta2-m were consistent with those of the colostral beta2-m. The urinary and colostral beta2-m possessed the same polypeptide chain consisting of 98 amino acids, and its molecular weight is 11.8 kDa. Furthermore, four isoforms of beta2-m were found. The isoelectric points were different from each other.

Amino Acid Sequence↗
PubMed2000

Localization and age-related changes in cytochrome P450 expression in APA hamster livers.

To establish the baseline data, age-related changes and the regional expression of the hepatic P450 isozymes in Syrian hamsters of the APA strain at 3, 6, 12, 18 months old were examined by immunological techniques. Immunohistochemical analysis of liver serial sections revealed that the midzonal and perivenous regions (zones 2 and 3, respectively) were stained with the anti-rat CYP1A1/2, 2B1/2 and 2E1 antibodies. These three antibodies most intensely stained the hepatocytes around the central vein. An anti-rat CYP3A2 staining section had a staining pattern with equally intense reactions in zones 2 and 3. On the other hand, CYP2C6, 2C11 and 4A1 were distributed diffusely throughout the hepatic acinus. There was no age-related difference in the expression pattern of any of the P450 isozymes examined. Total P450 content had a peak at 6 months of age and decreased to 60% of that level thereafter. Western-blot analysis revealed that the peak expressions of the isozymes detected with anti-rat CYP1A1/2, 2C6, 2E1 and 3A2 antibodies were observed in 6-month-old hamsters and declined in older ones. The CYP2B and 2C11 content reached the maximum at the age of 6 months and maintained almost the same level thereafter. The CYP4A level did not change from 3 to 6 months, and then declined to about 40% of the younger level at 12 and 18 months of age. These results suggest that the hepatic P450 isozymes of APA hamsters have region-specific expressions and most isozymes have their peaks of expression at 6 months of age, which differs from the patterns for rat P450.

Aging↗
PubMed2000

Aortic atheromatous lesions developed in APA hamsters with streptozotocin induced diabetes: a new animal model for diabetic atherosclerosis. 1. Histopathological studies.

To develop an adequate animal model for atherosclerosis in large vessels of patients with diabetes, i.e. diabetic macroangiopathy, we induced diabetes in APA hamsters with a single injection of streptozotocin (SZ) and examined the aorta histopathologically and immunohistochemically. As a result, hyperglycemia and hyperlipidemia were continuously observed for 26 weeks after the SZ injection (WAI) in APA hamsters. Fatty streaks characterized by a subendothelial accumulation of many foam cells were observed, limited to the aortic arches as early as 6 WAI. In addition to larger fatty streaks developing with the duration of diabetes, fibrous plaques and plaques containing calcium deposits or cholesterol clefts developed at 26 WAI. These lesions are generally similar to the atheromatous lesions developed in humans. Moreover, depositions of apolipoprotein E and advanced glycation end-products immunohistochemically detected in the lesions were very similar to those found in humans. The diabetic APA hamster is therefore considered to be a useful model for studying the formation of atheromatous lesions in diabetic patients.

Alloxan↗
PubMed2000

APA hamster model for diabetic atherosclerosis. 2. Analysis of lipids and lipoproteins.

Syrian hamsters of the APA strain (APA hamsters) have recently been shown to have atheromatous lesions in the aortic arches under diabetic condition induced by a single injection of streptozotocin (SZ). In that model, fatty streaks, which are the initial lesions of atherogenesis, develop by 6 weeks after the injection (WAI). In this study, we evaluated plasma lipid concentrations and lipoprotein profiles in diabetic APA hamsters at 6 WAI to reveal the early stage of atherogenesis clinicopathologically. As a result, by biochemical analysis, hyperglycemic APA hamsters showed signs of hypercholesterolemia and hypertriglyceridemia. Low-density lipoprotein (LDL) cholesterol significantly increased, but high-density lipoprotein (HDL) cholesterol significantly decreased. Agarose gel electrophoresis showed an obvious increase in the fractions of chylomicron, LDL and abnormal lipoprotein. Plasma LDL in diabetic animals was in a state more susceptible to oxidization. In addition, a significant increase in glycated LDL was also found in the diabetic animals by enzyme linked immunosorbent assay (ELISA). Moreover, lipid peroxidation product (4-hydroxynonenal (4 HNE))-adducted proteins and advanced glycation end-products (AGE) were immunohistochemically detected in the foam cells of the fatty streaks. These results revealed that diabetic APA hamsters had hyperlipidemia characterized by increases in chylomicron, LDL and abnormal lipoprotein, and suggested that oxidized LDL and/or glycated LDL might be actively uptaken by macrophages and play an important role in the initial stage of atherogenesis.

Aldehydes↗
PubMed2000

Clinical evaluation of 61 patients with pulmonary aspergilloma.

OBJECTIVE AND METHODS: We retrospectively evaluated 61 cases with pulmonary aspergilloma representing patients admitted to Nagasaki University Hospital between January 1991 to June 1998. RESULTS: Fifty-two (85%) were males and 9 (15%) were females, aged between 14 to 80 years (average, 65 years). Forty-four (72%) patients had history of old pulmonary tuberculosis. Chest radiographs showed "fungus ball" in the cavities in 42 (67%) cases while 16 (26%) cases showed thickening of the cavity wall. Aspergillus fumigatus was isolated in 24 (39%) patients. Aspergillus antigen or antibody was positive in 8 (13%) and 43 (70%) patients, respectively. Oral itraconazole was used in 16 (26%) of patients, and surgical excision was performed in 15 (25%) patients. During hospitalization or after discharge, 19 (31 %) patients died. SUMMARY AND CONCLUSION: Pulmonary aspergilloma usually occurs in elderly patients with old tuberculosis and respiratory failure. Many cases did not respond to antifungal therapy with itraconazole or amphotericin B. Our analysis indicates that more effective and appropriate therapeutic regimens are needed for the treatment of patients with pulmonary aspergilloma.

Adolescent↗
PubMed2000

Undefined complications of parathyroid adenoma, parathyroid hyperplasia (primary hyperparathyroidism), thyroid follicular adenoma, thyroid papillary carcinoma, temporal astrocytoma, cerebellar meningioma, and hemangioma of external auditory meatus and oral papilloma.

A 59-year-old woman who had parathyroid adenoma, parathyroid hyperplasia, thyroid follicular adenoma, thyroid papillary carcinoma, astrocytoma of the right temporal lobe, cerebellar meningioma, capillary hemangioma of the left external auditory meatus and papilloma of the left upper gingiva is reported. Dynamic magnetic resonance imaging, computed tomography with contrast-enhancement and gastrofiberscopy revealed no remarkable findings in the pituitary, pancreas, adrenals, stomach or duodenum. Similar lesions were not found in any family members. Defect of the causative genes of multiple endocrine neoplasia types I and IIa, MENIN and RET was not detected. Further follow-up of this patient and family members is needed.

Adenoma↗
PubMed2000

[Factors in continuation of home health care for patients with intractable neurological diseases].

OBJECTIVE: This study was carried out to elucidate factors related to difficulty in continuing home health care and to investigate problems of the corresponding support system for patients with intractable neurological diseases. SUBJECTS AND METHODS: Subjects were 139 cases of amyotrophic lateral sclerosis (ALS), 376 cases of spino-cerebellar degeneration (SCD) and 1,048 cases of Parkinson's disease (PD) who were collected from the nationwide survey of health and social service needs of the patients with intractable diseases in 1995. Factors and problems related to limited activity due to diseases and necessity for medical care were analysed. The need for facilities of long-term care was also studied. RESULTS: The characteristic conditions of patients with ALS were shorter duration of the illness, higher percentage of conditions requiring medical care and disorders of swallowing or respiration and full nursing care in daily life compared with the other two diseases. The characteristics of PD were higher percentage of female and older age in both patients and their family caregivers. The proportion of cases for whom health care was judged to be prone to difficulty was 23.0% in ALS, 10.9% in PD and 7.2% in SCD, respectively. Regarding the factors related to difficulty in continuing home health care, conditions requiring medical care, the need for full nursing care in daily life, and the duration of the illness were recognized in ALS. In SCD, 5 factors, including conditions requiring medical care, the need for full nursing care in daily life, patients age greater than 65 years, the duration of the illness, and patients being nursed by their sons or daughters were detected. In PD, 4 factors, such as conditions requiring medical care, the need for full nursing care in daily life, the patients being nursed by persons other than the spouse, and the need of nursing care were found. CONCLUSION: These results suggest the necessity of social functions of medical care, nursing and family support that can be supplied at home effectively according to symptoms in progress, and the need for facilities of long-term care of patients for whom continuation of home health care may become difficult, which will work as a support system for long-term care of patients with intractable neurological diseases.

Amyotrophic Lateral Sclerosis↗
PubMed2000

[A case of polypoid form of parameatal urethral cyst].

A 45-year-old man first noticed a soft tumor on his left lip of the urethral meatus at the age of 15. The lesion had gradually been increasing in size during the last 10 years. He presented to our clinic with division of urinary stream which had been persisting for about nine months. The tumor was resected, and histopathological examination revealed that it was a mucous cyst. The cyst had an outer wall of stratified squamous epithelium and an inner wall of stratified columnar epithelium. Since the inner wall was covered with epithelium originating from the urethral mucosa and the lesion was located outside the urethral meatus, a diagnosis of parameatal urethral cyst was made. Recently, parameatal urethral cyst has rarely been reported since it is often clinically in significant and remains asymptomatic. In our patient, the tumor showed polyploid growth and caused difficulty in urination. The mechanism of its development is considered based on a review of the literature.

Cysts↗
PubMed2000

[Vascular and metabolic reserve in a case of hypoplasia of bilateral internal carotid arteries].

We report a 64-year-old right-handed man who presented with a hypoplasia of bilateral internal carotid arteries (ICAs). The patient complained of a vertigo and was diagnosed as having a benign paroxysmal positional vertigo. Upon neurological examination, he was completely free from neurological deficits. MR angiogram revealed an occlusion of both ICAs. On conventional angiogram, the right ICA was occluded about 3 cm distal from its origin, and the left ICA was occluded at the precavernous portion. There was an abundant collateral blood flow to the frontal, temporal and parietal lobes through the posterior communicating arteries. Both carotid canals were hypoplastic on 3D-CT. The patient was then diagnosed as having a hypoplasia of both ICAs. Using a positron emission tomography (PET), cerebral blood flow (CBF), cerebral metabolic rate for oxygen (CMRO2), oxygen extraction fraction (OEF), and vascular transit time (VTT) were measured during resting state, and the vascular reactivities to carbon dioxide inhalation (VRCO2), and to the intravenous administration of Acetazolamide (VRACZ) were also evaluated. There was no global or focal reduction in CBF and VTT was within normal limit, whereas a global reduction of CMRO2 caused mild decrease in OEF. Moreover, VRACZ was significantly decreased and an intracerebral steal phenomenon was observed in the parietal cortical areas, whereas VRCO2 was preserved. The discrepancy between VRACZ and VRCO2 observed could be related to the differences in the mechanisms underlying the vasodilating effects of carbon dioxide and ACZ.

Arterial Occlusive Diseases↗