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Biomedical subjects

T Miyamoto

Publications and source records attributed to T Miyamoto.

At least 199 records · Page 11Linked to original sources
PubMed2000

Mechanism of liver-selective thyromimetic activity of SK&F L-94901: evidence for the presence of a cell-type-specific nuclear iodothyronine transport process.

The thyromimetic compound SK&F L-94901 shows more potent thyromimetic activity in the liver than in the pituitary gland or heart when administered to rats. The mechanisms of liver-selectivity of SK&F L-94901 were examined using cultured rat hepatoma cells (dRLH-84) and rat pituitary tumor cells (GH3), both of which showed saturable cellular uptake of tri-iodothyronine (T(3)). When isolated nuclei with partial disruption of the outer nuclear membrane were used, SK&F L-94901 competed for [(125)I]T(3) binding to nuclear receptors almost equally in dRLH-84 and GH3 cells. SK&F L-94901 also did not discriminate thyroid hormone receptors (TR) alpha1 and beta1 in terms of binding affinity and activation of the thyroid hormone responsive element. In intact cells, however, SK&F L-94901 was a more potent inhibitor of nuclear [(125)I]T(3) binding in dRLH-84 cells than in GH3 cells at an early phase of the nuclear uptake process and after binding equilibrium. These data suggest that SK&F L-94901 is more effectively transported to nuclear TRs in hepatic cells than in pituitary cells and therefore shows liver-selective thyromimetic activity. In conclusion, SK&F L-94901 discriminates hepatic cells and pituitary cells at the nuclear transport process. The cellular transporters responsible for this discrimination were not evident.

Animals↗
PubMed2000

The characteristics of fatigue symptoms and their association with the life style and the health status in school children.

In order to evaluate the characteristics of fatigue symptoms and their association with the life style and the health status, we examined using data accumulated by the longitudinal surveys from 1992 to 1998, in 118 six-year primary school children and 129 second-year junior high school children. The complaints of "drowsiness and dullness", such as "become drowsy" (71%), "give a yawn" (59%) and "want to lie down" (51%), respectively, were most frequently observed. The proportion of these complaints was high before the first morning class, but decreased when the children leave school. Notably, the complaints of "difficulty in concentration" annually have increased. Children with undesirable eating habits, particularly those who often eat salty foods, or poor life style, such as staying up late at night tended to have more complaints of fatigue symptoms. By correlation analysis, these complaints were significantly related to the obesity degree, blood pressure, HDL cholesterol and atherogenic index. These results support the hypothesis that fatigue symptoms increase or are associated with life style and health status. Consequently, it is necessary to improve the life style such as dietary habits and rhythm of life for the reduction of fatigue symptom.

Child↗
PubMed2000

Tracking of cardiovascular risk factors and a cohort study on hyperlipidemia in rural schoolchildren in Japan.

A cohort study was conducted to explore the tracking stability of cardiovascular risk factors and relative risk (RR) of factors relating hyperlipidemia in children. The percentages of children remaining persistently at high risk over a four-year tracking were as follows: body mass index (BMI) 65.0%, total cholesterol (T-c) 60.6%, atherogenic index (AI) 56.4%, high density lipoprotein cholesterol (HDL-c) 50.7%, systolic blood pressure (SBP) 44.2% and diastolic blood pressure (DPB) 39.6%. The order of correlation coefficients over four years was BMI > AI > HDL-c > T-c > SBP > DBP and these coefficients in boys were slightly higher than those in girls. The relative risk (RR) of BMI for AI > or = 3 was elevated (RR=4.36, 95% CI: 1.3-14.1). The incidence and RR for AI > or = 3 increased along with the addition of the selected risk factor number. The RR in children with three selected risk factors rose to 8.39 ( 95% CI: 1.2-38.7 ). The stability of tracking was better for BMI, T-c, AI and HDL-c. As the number of multiple factors increased, so did the RR of higher AI in childhood. These results suggest that preventive activities for hyperlipidemia should be focused on children with multiple cardiovascular risk factors.

Cardiovascular Diseases↗
PubMed2000

Coordinate regulation of matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 expression in human vascular smooth muscle cells.

The expression of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) by human vascular smooth muscle cells (SMC) was monitored as a function of the phenotypic modulation in vitro. Cell phenotype was manipulated by varying serum concentration and cell density. Synthetic phenotype was characterized by a minimum expression of the contractile proteins and a maximal proliferation rate. Contractile phenotype was quiescent and expressed a maximal level of contractile proteins. Synthetic cells expressed the highest levels of both MMP-1 and TIMP-1 and displayed maximal collagenolytic activity. No significant change was detected in MMP-2 expression or catalytic activity. Enzyme immunoassays revealed that MMP-1 expression fell by 77+/-2.4-95+/-0.5%, and that of TIMP-1 by 34+/-0.5-59+/-1.9%, as the cells acquired a contractile phenotype. The level of the MMP-1/TIMP-1 complex was similarly reduced by 78+/-2.9-85+/-1.6%. These data demonstrate that the expression of MMP-1 and TIMP-1 are coordinately regulated with SMC phenotype.

Adult↗
PubMed2000

Effect of thrombopoietin on acute myelogenous leukemia blasts.

It has been shown that the expression of c-mp1, which is a specific receptor for thrombopoietin (TPO), is restricted to the surface of megakaryocytes, platelets, human CD34+ progenitor cells and human erythroid/megakaryocytic leukemic cell lines. Recently, however, it has been reported that some acute myelogenous leukemia (AML) blasts expressed c-mp1 on their cell surface and proliferated in response to TPO. We therefore investigated the effect of thrombopoietin on the growth of leukemic blasts from patients with CD7-positive acute myelogenous leukemia (AML), which is a distinct biological and clinical subtype of AML. Significant growth responses of leukemic blasts to TPO were seen in 10/10 CD7+ and 7/20 CD7- AML cases using 3H-thymidine incorporation, while synergistic stimulatory effects of TPO with stem cell factor (SCF), interleukin-3 (IL-3), granulocyte colony-stimulating factor, and granulocyte-macrophage colony-stimulating factor were observed in both groups. In a leukemic blast colony assay, significant growth response to TPO was observed in 5/6 CD7+ and 4/17 CD7- AML cases examined. Furthermore, the expression of c-mp1 seemed to be higher in CD7+ AML cases than in CD7- cases, suggesting a relationship between the expression of c-mp1 and the proliferative response to TPO. These findings imply that CD7+ leukemic blasts express functional TPO receptors and proliferate in response to TPO. Thus CD7 expression on AML blasts may indicate the involvement of leukemic progenitors at an early stage of multipotent hemopoietic stem cells. In this review, we discuss the effect of TPO on AML blasts, especially in CD7+ AML cases.

Animals↗
PubMed2000

Rapid detection of enterotoxigenic Escherichia coli O6 in water by using monoclonal antibody and a photon-counting television camera.

Monoclonal antibodies (MAbs) raised against Escherichia coli O6:H16 were screened against 15 strains of E. coli and 19 non-E. coli bacteria. A MAb-luminescence assay using MAb-5.8, which shows no cross-reactions with non-E. coli bacteria, and a photon-counting television camera were developed for rapid enumeration of E. coli O6:H16 in water. The membrane filter that retained bacteria was boiled for 5 min in a buffer and incubated with biotinylated MAb-5.8. After incubation with streptavidin-peroxidase conjugate, it was reacted with luminol-based reaction mixture. Luminous image and light intensity of the filter was recorded with a Biocell Counter. Levels of E. coli O6 higher than 7 x 10(3) CFU were detected by the MAb-luminescence assay when E. coli O6 was spotted onto the membrane filter. The sample that contained E. coli O6:H16 was filtered through a membrane filter, and the filter that retained bacteria was incubated on a filter paper soaked with nutrient broth supplemented with 0.5% NaCl at 37 degrees C for 6 h. The number of light emission points on the filter correlated well with initial E. coli O6:H16 counts within the range of 1 to 3 x 10(2) CFU. The correlation coefficient was 0.89.

Antibodies, Monoclonal↗
PubMed2000

[Hospitalization reduction by an asthma tele-medicine system].

We examined an effectiveness of a new asthma telemedicine system in reducing hospitalizations using a multi-site randomized control study. In this program, a nurse under physician supervision monitors the patient's airway status at home and provides instructions to individuals via the telephone, helping them manage exacerbations as well as reinforcing proper use of a zone-controlled management plan. Patients with a high risk for hospitalization were screened based on the numbers of emergency room visits and hospitalizations found in a previous study and randomly assigned to either the telemedicine or control group. After a six-month study period, an 83% reduction in hospitalization was demonstrated in the telemedicine group versus the control group, with a P value of 0.01. Improvement of peak expiratory flow and symptoms were also shown in the study group. We conclude that the key success factors in home asthma management for poorly controlled asthma patients are early detection of exacerbations through daily peak flow monitoring, compliance with prescribed daily prophylactic anti-inflammatory steroid medications, and immediate action as specified by a zone-controlled action plan upon the first signs of deterioration.

Aged↗
PubMed2000

The benefits and new predictors of early extubation following coronary artery bypass grafting.

OBJECTIVE: This study researched cardiorespiratory effects and cost-effectiveness of early extubation in patients following coronary artery bypass grafting. METHODS: We retrospectively examined the character of 86 (38 preoperative, 12 intraoperative, 36 postoperative) variables in 78 patients after coronary artery bypass grafting (CABG) at our hospital. The patients were classified into three groups according to the time of extubation: Group A (less than 8 hours), Group B (8 to 24 hours) and Group C (24 hours or more). RESULTS: There were 43 patients in Group A (55%), 27 patients in Group B (35%), and 8 patients in Group C (10%). Univariate preoperative analysis revealed several differences between Groups A and B: 15 variables were found to reach statistical significance. Stepwise logistic regression analysis implicated decreased forced expiratory volume rate in the first second (FEV1.0%), postoperative cardiac index (CI) after admission to the intensive care unit (ICU) and usage of postoperative temporary pace-makers as predictors of late extubation. Also, there was a statistical significance in usage of diuretics within the first day (15.8+/-11.6 vs 28.8+/-22.6 mg; p = 0.044) and in the ICU days (3.6+/-0.8 vs 4.2+/-1.0; p = 0.004) between early and late extubation groups. CONCLUSIONS: Early extubation within 8 hours into the ICU stay was accomplished in 55% of the patients in this study. We speculate that the benefits of early extubation contain improvement of cardiac function, reduction in respiratory infection and complications, and cost saving as the result of diminished ICU admission. Also, we have shown that decreased FEV1.0%, decreased CI and the usage of a postoperative temporary pacemaker were independent predictors of prolonged intubation in our study.

Aged↗
PubMed2000

[Necessity of permanent anticoagulant therapy for isolated mitral valve replacement with bioprosthetic heart valve to prevent the postoperative thromboembolic complications].

One hundred fifty four patients underwent isolated mitral valve replacement with bioprosthetic heart valve at Hyogo Medical College Hospital from November 1973 to December 1998. A porcine bioprosthetic valve was replaced in 82 patients (Hancock 43, Carpentier-Edwards 26, Hancock II 13) and pericardial bioprosthetic valve in 72 patients (Ionescue-Shiley 39, Carpentier-Edwards 33) with a mean follow-up of 1,410 patients-years. Their thromboembolism rates were also analyzed in linear and actuarial term over the 15-year period. The incidence of thromboembolism rate was 2.5%/pt.yr. Thromboembolic free rates for patients with anticoagulant therapy were significantly decreased for patients without therapy. Thromboembolic free rates for patients with atrial fibliration were also were significantly decreased for patients with sinus rhythm because the patients with sinus rhythm were not on anticoagulant therapy. In conclusion, it is necessary for the all patients to be on anticoagulant therapy after mitral valve replacement with bioprosthetic valves, even though patients with sinus rhythm.

Adult↗
PubMed2000

Interleukin (IL)1beta, IL-1alpha, and IL-1 receptor antagonist gene polymorphisms in patients with temporal lobe epilepsy.

Proinflammatory cytokines, including interleukin (IL)-1beta, are known to modulate effects of neurotoxic neurotransmitters discharged during excitation or inflammation in the central nervous system (CNS). They also regulate development of glial scars at sites of CNS injury. To elucidate a genetic predisposition of temporal lobe epilepsy with hippocampal sclerosis (TLE-HS+), we studied polymorphisms in the IL-1beta, IL-1alpha, and IL-1 receptor antagonist (IL-1RA) genes in 50 patients with TLE-HS+ and in 112 controls. Fifty-three patients who had TLE without HS were also examined (TLE-HS-) as disease controls. The distribution of the biallelic polymorphism in the promoter region at position -511 of the IL-1beta gene (IL-1B-511) was significantly different both between TLE-HS+ patients and controls and between TLE-HS+ and TLE-HS- patients. The differences were due to overrepresentation of the homozygotes for IL-1B-511*2, which is suggested to be a high producer of IL-1beta, in TLE-HS+ patients compared with both controls and TLE-HS- patients. In contrast, there was no difference between TLE-HS- patients and controls. Our data suggest that, in the homozygotes for IL-IB-511*2, minor events in development such as febrile convulsions could set up a cascade leading to HS.

Adult↗
PubMed2000

[Evaluation of MAST-26, newly developed system for the detection of IgE antibodies].

MAST-26 is a new allergy testing system which allows simultaneous determination of allergen-specific IgE antibody levels for 26 allergens using 200 microliters of patient serum. To evaluate the effectiveness of MAST-26 for the detection of allergen-specific IgE antibody, a total of 100 serum samples were collected from allergic patients at five facilities, and allergen-specific IgE antibody was measured by MAST-26. 14% of them were positive to > or = 10 allergens. If the patients had severe allergic symptoms, they were likely to show positive to many allergens. A good correlation was found between the results obtained by MAST-26 with those measured by CAP RAST and by intradermal skin test. It was concluded that MAST-26 is an effective screening method for the detection of allergen-specific IgE.

Allergens↗
PubMed2000

[Modified extended septoplasty for left ventricular outflow tract obstruction after repair of double-outlet right ventricle report of a case].

A three-year-old boy with residual VSD and LVOTO after repair of double outlet right ventricle underwent modified extended septoplasty successfully. Preoperative left ventriculography showed a residual VSD and LVOTO. The peak systolic pressure gradient between the left ventricle and aorta was 38 mmHg. Operation aimd not only at relief of the obstruction, but also at streamlining of the LVOT by removal of protrusions. We modified the extended septoplasty reported by Belli et al in 1996. The postoperative course was uneventful and patient was discharged at 15 postoperative day. The most recent echocargiogram revealed no residual LVOTO.

Cardiac Surgical Procedures↗
PubMed2000

[Prolactinoma in a child showing high MIB-1 labeling index: a case report].

We report a very rare case of a prolactin secreting pituitary tumor (prolactinoma) which occurred in a 12-year-old boy. The tumor showed an extremely high MIB-1 index. The clinical implication in the postoperative management of childhood prolactinoma is discussed. The patient showed right third nerve palsy, and MRI revealed a pituitary tumor invading the right cavernous sinus. Preoperative hormonal evaluation showed a very high prolactin level (2800 ng/ml). The patient underwent transsphenoidal surgery, and the third nerve palsy disappeared just after the procedure. MIB-1 index obtained by using immunostaining was 18.9%. Postoperative prolactin level remained high (2200 ng/ml), and the patient was treated with 10 mg/day of bromocriptine. Prolactinomas in children with high MIB-1 index show resistance to treatment with bromocriptine. In the postoperative management of a childhood prolactinoma, it should be considered how to control sufficiently high serum prolactin level to expect sexual development while preserving other normal residual pituitary functions. If control with bromocriptine, fails radiation treatment should be adopted with careful observation of the increase in height and the progress of sexual development of the patient.

Bromocriptine↗
PubMed2000

[A case of multiple sclerosis with hypothalamic amenorrhea].

We present a 31-year-old woman of multiple sclerosis. At age 28, she was admitted with complaints of echolalia and a gradual onset of weakness affecting the right upper and bilateral lower limbs. Brain MRI showed high intensity areas in the bilateral frontal gyri, lobuli paracentralis, and left anterior thalamus. Although she had been in remission for 3 years, she developed dysesthesia of left upper and lower limbs. Cervical T2 weighted MRI showed a new high signal intensity lesion in the spinal cord from the C2 to C3 level. The combination of the cerebral, thalamic and spinal cord lesions with remission and excerbations allowed the diagnosis of clinically MS to be made. She suffered amenorrhea from the onset of her illness. Serum prolactin was within the normal range. The LH and FSH basal secretions were decreased and there were low delayed secretions of LH and FSH after intravenous injection of 100 micrograms LHRH. We consider that her amenorrhea was caused by the hypothalamic lesion, supported by MR findings of dilatation of the third ventricle.

Adult↗
PubMed2000

[5-FU concentration in the serum and the tumor tissue after administration of UFT 200 mg/day to patients over 80 years of age with oral cancer].

UFT was administered orally at a dosage of 200 mg/day, 2 times a day, to patients over 80 years of age with oral cancer. The concentration of 5-FU in the serum and tumor tissue, as well as the side effects, were investigated. The results were as follows: 1. The concentration of 5-FU in the serum peaked (0.017 to 0.066 microgram/ml) 1 or 2 hours after UFT administration. The concentration 8 hours after administration was relatively high (0.016 to 0.041 microgram/ml). 2. The 5-FU concentrations in the tumor tissues in 3 out of 5 cases were greater than 0.05 microgram/g, which is considered to be the effective level. The concentration tended to be higher with increased duration of administration. 3. A minor side effect, bone marrow dysfunction, was observed. No effect on the function of the liver or digestive system was observed.

Aged↗