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Biomedical subjects

K Tsuda

Publications and source records attributed to K Tsuda.

At least 73 records · Page 4Linked to original sources
PubMed1999

Disordered expression of the sucrase-isomaltase complex in the small intestine in Otsuka Long-Evans tokushima fatty rats, a model of non-insulin-dependent diabetes mellitus with insulin resistance.

To clarify the relationship between diabetes mellitus and carbohydrate digestion, the activities of sucrase and isomaltase, which form a complex enzyme (SI complex) on the brush border membranes, were compared in the progression of diabetes mellitus in Otsuka Long-Evans Tokushima fatty (OLETF) rats, a model of human non-insulin-dependent diabetes mellitus with insulin resistance, and Long-Evans Tokushima Otsuka (LETO) rats as non-diabetic controls. Until 40 weeks of age, OLETF rats were obese and had a high plasma glucose level, compared to age-matched LETO rats, but the sucrase and isomaltase activities showed no significant differences between the two strains. Oral glucose tolerance test revealed that during 40-48 weeks of age, NIDDM became very severe with advancing insulin resistance in OLETF rats. In OLETF rats, in contrast to LETO rats, at 48 weeks of age, abnormal increases in the sucrase and isomaltase activities occurred, along with a remarkable decrease in body weight and a further great increase in the plasma glucose level in the non-fasting state. Hyperinsulinemia occurred in 20-week-old OLETF rats; however, at 40 and 48 weeks of age, the plasma insulin level in the non-fasting state in OLETF rats was not significantly different from that in LETO rats. The level of mRNA encoding the SI complex increased abnormally in 48-week-old OLETF rats. These results suggest that the advance of insulin resistance leads to an increase in the expression of the SI complex on the transcriptional level.

Age Factors↗
PubMed1999

MR imaging of non-squamous vaginal tumors.

We reviewed the MR images and pathologic findings of five cases of primary vaginal neoplasms of non-squamous origin. Histologic types consisted one case each of adenocarcinoma, adenosarcoma, melanoma, lymphoma, and neurilemoma. Magnetic resonance imaging was found useful for evaluating the type and the extension of vaginal tumors.

Adult↗
PubMed1999

Tubal pregnancy in a unicornuate uterus with rudimentary horn: a case report.

OBJECTIVE: To report a case of tubal pregnancy in a unicornuate uterus with rudimentary horn on the side of the rudiment and its pathology. DESIGN: Case report. SETTING: University hospital. PATIENT: An 18-year-old woman, primigravida, with tubal pregnancy. INTERVENTION(S): Systemic administration of methotrexate, salpingectomy by laparotomy, and laparoscopic surgery for resection of rudimentary horn. MAIN OUTCOME MEASURE(S): Emergent laparotomy revealed that the intraperitoneal hemorrhage was caused by the rupture of the tubal pregnancy on the same side as the rudimentary horn of the unicornuate uterus. A corpus luteum was found at the ipsilateral ovary of the rudimentary horn. RESULT(S): Image diagnosis and pathological examination of the rudimentary horn revealed that this uterine malformation was a unicornuate uterus with a noncommunicated, noncavitary rudimentary horn, corresponding to class IIc of the American Fertility Society classification of müllerian anomalies. CONCLUSION(S): This is the first report of a tubal pregnancy on the side of the noncommunicating rudimentary horn with the ipsilateral ovary carrying a corpus luteum in a unicornuate uterus.

Abortifacient Agents, Nonsteroidal↗
PubMed1999

Nisoldipine improves the impaired erythrocyte deformability correlating with elevated intracellular free calcium-ion concentration and poor glycaemic control in NIDDM.

AIMS: To explore the mechanisms underlying the impaired erythrocyte deformability (RBC-df) in diabetic patients, the relationship between erythrocyte intracellular free calcium-ion concentration ([Ca2+]i) and RBC-df, and the effects of Ca2+-channel blocker on [Ca2+]i and RBC-df were evaluated. METHODS: Forty-eight patients with NIDDM and 24 control subjects were enrolled in this study. [Ca2+]i was determined using fura-2, and RBC-df by filtration method expressed as Deformability Index (DI). Erythrocytes were treated with nisoldipine to evaluate the effects of a Ca2+-channel blocker. RESULTS: [Ca2+]i was significantly higher (82.6 (78.0-87.2) vs 76.6 (74.3-81.2) nmol lRBC-1, P<0.001), and DI was significantly lower (0. 14 (0.09-0.28) vs 0.22 (0.16-0.28), P<0.01) in NIDDM than in controls. There was a significant correlation between HbA1c and [Ca2+]i (r=0.38, P<0.01), between HbA1c and DI (r=-0.51, P<0.01), and between [Ca2+]i and DI (r=-0.42, P<0.01). Stepwise multiple regression analysis revealed HbA1c and [Ca2+]i as independent determinants for the impaired RBC-df. Nisoldipine treatment in vitro significantly decreased [Ca2+]i, and significantly improved RBC-df. CONCLUSIONS: These data indicate that the impaired RBC-df in NIDDM may at least partly be attributed to the elevated [Ca2+]i and poor glycaemic control. In addition, favorable effects of a Ca2+-channel blocker on both [Ca2+]i and RBC-df have been demonstrated.

Adult↗
PubMed1999

A new 200 kV Omega-filter electron microscope.

A new 200 kV Omega-filter electron microscope was developed under a project supported by a Grant-in-Aid for Specially Promoted Research of the Ministry of Education, Science, Sports and Culture of Japan. The performance of the microscope is described.

Journal Article↗
PubMed1999

Non-linear analysis of the sleep EEG.

A sleep electroencephalogram was analyzed by non-linear analysis. The polysomnography of a healthy male subject was analyzed and the correlation dimensions calculated. The correlation dimensions decreased from the 'awake' stage to sleep stages 1-3 and increased during rapid eye movement (REM) sleep. These results were seen during each sleep cycle. In each sleep cycle, the correlation dimensions decrease for slow wave sleep, and increase for REM sleep.

Adult↗
PubMed1999

Adrenomedullin and membrane fluidity of erythrocytes in mild essential hypertension.

OBJECTIVE: Adrenomedullin is a newly discovered 52 amino acid peptide that has a potent vasodilating action. The present study was undertaken to investigate the role of adrenomedullin in the regulation of membrane fluidity of erythrocytes in patients with essential hypertension. METHODS AND RESULTS: We used an electron paramagnetic resonance and spin-labeling method. Adrenomedullin significantly decreased the order parameter for 5-nitroxide stearate and peak height ratio for 16-nitroxide stearate obtained from electron paramagnetic resonance spectra of erythrocyte membranes in normotensive volunteers (mean +/- SEM order parameter value: control, 0.718 +/- 0.003, n = 16; adrenomedullin at 10(-9) mol/l, 0.692 +/- 0.004, n = 16, P < 0.05; adrenomedullin at 10(-8) mol/l, 0.690 +/- 0.004, n = 16, P < 0.05; adrenomedullin at 10(-7) mol/l, 0.683 +/- 0.004, n = 16, P < 0.05). The findings showed that adrenomedullin increased the membrane fluidity of erythrocytes. In addition, the effect of adrenomedullin was significantly potentiated by prostaglandin E1 and dibutyryl cyclic AMP. In contrast, the calcium ionophore A23187 counteracted the actions of adrenomedullin. In patients with essential hypertension, who had higher order parameter values, the membrane fluidity of erythrocytes was significantly lower than in the normotensive control subjects (order parameter: 0.728 +/- 0.004 in hypertensives, n = 20; 0.692 +/- 0.002 in normotensives, n = 36, P < 0.01). The effect of adrenomedullin on membrane fluidity was more pronounced in the erythrocytes of essential hypertensive than in the erythrocytes of normotensive subjects (change in the order parameter with adrenomedullin at 10(-9) mol/l: -4.2 +/- 0.3% in hypertensives, n = 20; -1.8 +/- 0.2% in normotensives, n = 20, P < 0.05; adrenomedullin at 10(-8) mol/l: -4.5 +/- 0.3% in hypertensives, n = 20; -1.8 +/- 0.2% in normotensives, n = 36, P < 0.05). CONCLUSIONS: The results of the present study demonstrate that adrenomedullin significantly increased the membrane fluidity of erythrocytes. The mechanisms were partially mediated by a prostaglandin E1- and cyclic AMP-dependent pathway which might be linked to changes in intracellular calcium kinetics. The greater effect of adrenomedullin in patients with essential hypertension suggests that the peptide might actively participate in the regulation of membrane functions in hypertension.

Adrenomedullin↗
PubMed1999

Effects of swimming training on aerobic capacity and exercise induced bronchoconstriction in children with bronchial asthma.

BACKGROUND: A study was undertaken to determine whether swimming training improved aerobic capacity, exercise induced bronchoconstriction (EIB), and bronchial responsiveness to inhaled histamine in children with asthma. METHODS: Eight children with mild or moderate asthma participated in swimming training every day for six weeks. The intensity of training was individually determined and set at 125% of the child's lactate threshold (LT), measured using a swimming ergometer. Another group of eight asthmatic children served as control subjects. Aerobic capacity and the degree of EIB were assessed by both cycle ergometer and swimming ergometer before and after swimming training. RESULTS: The mean (SD) aerobic capacity at LT increased by 0.26 (0.11) kp after training when assessed with the swimming ergometer and by 10.6 (4.5) W when assessed with the cycle ergometer, and these changes were significantly different from the control group. The mean (SD) maximum % fall in forced expiratory volume in one second (FEV1) to an exercise challenge (cycle ergometer) set at 175% of LT decreased from 38.7 (15.4)% before training to 17.9 (17.6)% after training, but with no significant difference from the control group. There was, however, no difference in histamine responsiveness when compared before and after the training period. CONCLUSION: A six week swimming training programme has a beneficial effect on aerobic capacity but not on histamine responsiveness in children with asthma.

Asthma↗
PubMed1999

A case of ALK-positive large T-cell lymphoma expressing epithelial membrane antigen with favorable prognosis.

We describe the case of a 59-year-old woman with Ki-1-negative, T cell-type, anaplastic lymphoma kinase (ALK)-positive large cell lymphoma that was positive for epithelial membrane antigen. She was histopathologically diagnosed as having a metastatic undifferentiated carcinoma from a cervical lymph node biopsy. Clinical and radiographic studies revealed no other primary tumor. The patient underwent a left radical neck dissection. Surgically resected lymph nodes revealed an ALK1-positive large cell lymphoma. Thereafter the patient has had an unusually favorable prognosis.

Anaplastic Lymphoma Kinase↗
PubMed1999

The association between Trp64Arg polymorphism of the beta3-adrenergic receptor and autonomic nervous system activity.

The beta3-adrenergic receptor plays a significant role in the control of lipolysis and thermogenesis in brown adipose tissue through autonomic nervous system (ANS) activity. As the Trp64Arg polymorphism of the beta3-adrenergic receptor gene might affect ANS activity, we investigated the association of the polymorphism with ANS activity. The prevalence of the polymorphism was determined in 204 subjects. Ten normal homozygous, 10 heterozygous, and 1 variant homozygous subjects were examined for ANS activity during supine rest and standing by electrocardiogram R-R interval power spectral analysis. Subjects with the variant did not differ from subjects without the variant in body mass index, plasma glucose, plasma insulin, or family history of diabetes or obesity. The total power of heterozygotes at supine rest was lower than that of normal subjects (1124.6 +/- 191.6 vs. 3029.8 +/- 758.8 ms2; mean +/- SE). With a postural change to standing, the parasympathetic and sympathetic nervous system activity indexes of heterozygotes showed a higher response than those of normal subjects (parasympathetic nervous system index, 0.10 +/- 0.02 vs. 0.17 +/- 0.02; sympathetic nervous system index, 10.55 +/- 1.47 vs. 6.26 +/- 1.09), and the difference in total power disappeared. These findings show that subjects with the variant, even the heterozygotes, had lower resting ANS activity than normal subjects.

Adult↗
PubMed1999

Diffusion-weighted single-shot echoplanar MR imaging for liver disease.

OBJECTIVE: The aims of this study were to determine apparent diffusion coefficients (ADCs) of the abdominal organs and liver lesions, to determine the effect of the magnitude of b values on the ADCs, and to determine whether measured ADCs of liver tumors help differentiate benign from malignant lesions. SUBJECTS AND METHODS: Six healthy volunteers and 126 patients were examined with diffusion-weighted single-shot echo-planar imaging using multiple b values (maximum, 846 sec/mm2). The ADCs of the liver, spleen, kidney, 49 malignant liver lesions (33 hepatocellular carcinomas, 15 metastatic liver tumors, and one cholangiocellular carcinoma), and 30 benign lesions (17 cysts, 12 hemangiomas, and one angiomyolipoma) were calculated. RESULTS: The ADCs of the abdominal organs and liver lesions showed smaller values when calculated with the greater maximum b values. The ADCs of the benign lesions calculated with all the b values of less than 850 sec/mm2 (2.49+/-1.39 x 10(-3) mm2/sec) were significantly (p = .0024) greater than those of the malignant lesions (1.01+/-0.38 x 10(-3) mm2/sec). When the maximum b value is 846 sec/mm2, use of a threshold ADC of 1.6 x 10(-3) mm2/sec would result in a sensitivity of 98% and a specificity of 80% for differentiation of malignant liver lesions from benign lesions. CONCLUSION: Measurement of ADC has good potential for characterizing liver lesions, but the calculated ADCs could be affected by the magnitude of the maximum b value.

Adult↗
PubMed1999

Arterial relaxation mediated by endothelium-derived hyperpolarizing factor in hypertension induced by chronic inhibition of nitric oxide synthesis.

The aim of this study was to evaluate arterial relaxation mediated by endothelium-derived hyperpolarizing factor (EDHF) during chronic inhibition of nitric oxide (NO) synthase. We measured the isometric tension of isolated mesenteric arteries of Wistar rats administered Nomega-nitro-L-arginine methyl ester (L-NAME, 100 mg/Kg/day) for 3 weeks. Relaxation to acetylcholine (ACh) was reduced in L-NAME treated rats (maximum relaxation, 52% versus 79% ). After acute superfusion of 1x10(-4) M L-NAME, half the relaxation was inhibited in controls, while the relaxation was not changed in L-NAME treated rats. In contrast, relaxation to nitroprusside was normal in L-NAME treated rats. Superfusion of 1x10(-6) M apamin, which inhibits the effects of EDHF, reduced the relaxation. The relaxation inhibited by apamin was not significantly different between the two groups. These findings suggested that in endothelial cells, the synthesis of EDHF is unchanged during a chronic deficiency of relaxation influence of NO.

Acetylcholine↗
PubMed1999

[The role and significance of acid suppressive drugs in the eradication of H. pylori].

Recently a new triple therapy with PPI and two antimicrobials is widely accepted instead of classical triple therapy. PPI has direct and indirect effects on H. pylori. Practically a single use of PPI is almost noneffective for eradication of H. pylori. In the combination therapy PPI is supposed to contribute to successful eradication through the inhibition of acid secretion. Because a raise of pH in stomach protects antimicrobials from the degradation by acidic environment. The decrease in the volume of gastric juice also contributes to concentrate antibiotics. Recently interaction between PPI and clarithromycin on metabolic enzyme in liver was reported that explains the synergistic effects of these drugs. The heterogeneity of genotype of metabolic enzyme was also elucidated which might be responsible for the difference in the effect of PPI between the patients. To accomplish successful eradication, full inhibition of acid secretion has to be done. To consider the interactions between PPI and antimicrobials and the heterogeneity of genotype of metabolic enzyme may improve eradication therapy of H. pylori.

Anti-Bacterial Agents↗
PubMed1999

[Change in prevalence of allergic diseases in primary school children in Fukuoka City for the last fifteen years].

We have been investigating the yearly change of prevalence rate of childhood allergic diseases using same method and in same region in five primary schools in Fukuoka City for the last fifteen years. From 1981 to 1995, revised ATS-DLD questionnaire had been administered yearly to the first graders of primary school children (6-7 yrs). The total number of subjects for fifteen years were 8000. The average number of children in each year was 533. 1. The cumulative prevalence of bronchial asthma statistically increased from 5.7% (average of 1981 to 1983) to 7.7% (1993 to 1995). It was 1.7 times higher on boys. 2. The cumulative prevalence of atopic dermatitis did not change yearly and its average was 36.3%. The boys/girls ratio was 1.2. Remission rate of atopic dermatitis statistically increased from 14.3% (average of 1987 and 1988) to 19.6% (1994 and 1995). 3. The cumulative prevalence of allergic rhinitis did not change yearly and its average was 17.6%. It was 1.5 times higher on boys. 4. The cumulative prevalence of allergic conjunctivitis statistically increased from 8.4% (average of 1987 and 1988) to 11.1% (1994 and 1995).

Child↗
PubMed1998

Transcriptional repressors are increased in pancreatic islets of type 2 diabetic rats.

To further clarify the mechanism of impaired insulin gene transcription in the diabetic state, we investigated the expression and function of the transcriptional repressor CREM (CRE modulator) in rat pancreatic islets. The CREM gene generates both transcriptional activators and repressors by alternative splicing and an intronic promoter. We isolated a novel alternatively spliced CREM isoform, CREM-17X, which efficiently represses insulin gene transcription, in addition to the three previously reported repressors. We also compared mRNA levels of insulin and the CREM repressors in pancreatic islets of Wistar and GK (Goto-Kakizaki) rats, the well-characterized spontaneous animal model of type 2 diabetes. The CREM repressor levels are increased, and the expression of insulin mRNA is decreased in GK rats, suggesting that increased CREM repressor expression in pancreatic islets could contribute to the decreased insulin gene transcription that results in impaired insulin secretion in type 2 diabetes.

Animals↗
PubMed1998

Mitochondrial abnormalities in selenium-deficient myopathy.

We report a man who developed selenium-deficient myopathy during long-term parenteral nutrition. Muscle biopsy showed marked mitochondrial depletion in the deep sarcoplasm and enlarged mitochondria at the periphery mainly in type 2 fibers. Muscle weakness improved gradually after the second course of selenium supplementation. The peculiar mitochondrial abnormalities in muscle fibers appear to play a key role in the pathogenesis of selenium-deficient myopathy.

Adult↗
PubMed1998

Properties of a new picorna-like virus of the brown-winged green bug, plautia stali

A picorna-like virus was isolated from the brown-winged green bug, Plautia stali. The virus was named Plautia stali intestine virus (PSIV) based on the multiplication site of the virus in the infected insects. PSIV is a spherical particle with a diameter of 30 nm. Particles of PSIV were found to contain a 9.1-kb single-stranded RNA. Polyacrylamide gel electrophoresis of purified PSIV particles revealed three major (33, 30, 26 kDa), one medium (35 kDa), and one minor (4.5 kDa) structural proteins. The molar ratios of the proteins suggested that the 35-, 33-, 30-, 26-, and 4.5-kDa proteins corresponded to VP0, VP1, VP2, VP3, and VP4 of vertebrate picornaviruses. Immunological assays indicated that PSIV and Nezara viridula virus-1, which is a picorna-like virus of the green stinkbug in South Africa, were serologically distinct. PSIV was detected in the intestine with enzyme-linked immunosorbent assay but not in the salivary glands, fat bodies, Malpighian tubules, and reproductive organs of viruliferous P. stali. The virus was also detected on the surface of the eggs and in the feces of infected insects. These results suggest that excrement of infected insects are the primary inoculum of the virus in a colony of P. stali. The nonviruliferous adults of P. stali usually survive a few months in laboratory, while the average of adulthood lifetime in viruliferous P. stali was about 13 days. PSIV also infected two other stinkbugs, Nezara viridula and Halyomorpha halys. Copyright 1998 Academic Press.

Journal Article↗