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Biomedical subjects

H Shimizu

Publications and source records attributed to H Shimizu.

At least 145 records · Page 8Linked to original sources
PubMed2001

Soy product intake and hot flashes in Japanese women: results from a community-based prospective study.

The association between soy product intake and the occurrence of hot flashes was examined in a cohort of 1,106 female residents of Takayama, Gifu, JAPAN: The women were aged 35-54 years and premenopausal at their entry into the study in 1992. Diet, including intake of soy products and isoflavones, was assessed by means of a validated semiquantitative food frequency questionnaire at study entry. A follow-up mail questionnaire asking about experiences of hot flashes was sent in 1998. During the 6 years of the study period, 101 women had new moderate or severe hot flashes according to the Kupperman test of menopausal distress. After data were controlled for age, total energy intake, and menopausal status, hot flashes were significantly inversely associated with consumption of soy products in terms of both total amount (highest tertile of soy product intake (g/day) vs. lowest: hazard ratio = 0.47; 95% confidence interval: 0.28, 0.79; p for trend = 0.005) and isoflavone intake (highest tertile of isoflavone intake (mg/day) vs. lowest: hazard ratio = 0.42; 95% confidence interval: 0.25, 0.72; p for trend = 0.002). These data suggest that consumption of soy products has a protective effect against hot flashes.

Adult↗
PubMed2001

Clinical and physiological significance of abnormally prolonged central motor conduction time in HAM/TSP.

We measured the central motor conduction time (CMCT), central sensory conduction time (CSCT), F wave and mean F wave/M wave amplitude ratio in patients with HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP) and controls. CMCTs in upper (U) and lower (L) limbs were significantly prolonged in HAM/TSP. L-CSCT was significantly prolonged in HAM/TSP, but U-CSCT in HAM/TSP and controls were not significantly different. CMCT and CSCT were significantly correlated in HAM/TSP. U-CMCT, but not L-CMCT, correlated with the clinical severity of HAM/TSP. Although F wave conduction velocity and its occurrence were normal in HAM/TSP, U- and L-mean F wave/M wave amplitude ratio tended to be higher in HAM/TSP, and the L-mean F wave/M wave amplitude ratio was significantly correlated with the L- and thoracic CMCT. These findings demonstrate that the prolongation of CMCT sensitively reflects the extension of the lesions and the disinhibition to the anterior horn cells in HAM/TSP.

Aged↗
PubMed2001

Cortical oscillations in human medial temporal lobe during wakefulness and all-night sleep.

We have recorded human medial temporal lobe electrocorticogram during wakefulness and natural sleep in epileptic patients with subdural electrodes. From these recordings, we have found gamma (30-150 Hz) [Neuroscience 90 (1999) 1149] and beta-1 (10-20 Hz) [NeuroReport 10 (1999) 3055] activities during wakefulness in human medial temporal lobe. In this paper, we will report changes of these frequencies across wake and natural sleep. Electrocorticograms during wake, slow wave sleep and rapid eye movement (REM) sleep were subjected to fast Fourier transformation analysis. During wake two spectral enhancements, beta-1 and gamma, were consistently observed across subjects. In the raw signal, beta-1 was observed as a regular rhythmic oscillation. In slow wave sleep, the beta-1 peak disappeared but gamma remained, although slightly reduced in power. During REM sleep, beta-1 appeared again, but the peak frequency was significantly lower than during wake (mean frequency: wake=16.6, REM=12.8 Hz). The gamma peak was also present in REM sleep. It has been known that the rhythmic slow activity (RSA) or theta is observed in some animals. However, it is unclear whether the human hippocampus displays similar activity. Since human beta-1 appears during wake and REM sleep when RSA is observed in other species, and since beta-1 is also a regular rhythmic oscillation, we propose that beta-1 may be the functional equivalent of hippocampal RSA (theta) observed in some animals. Functional significances of the gamma activity should be further investigated.

Adult↗
PubMed2001

Nitric oxide synthase activity in peripheral polymorphonuclear leukocytes in patients with chronic congestive heart failure.

Increased activity of inducible nitric oxide synthase (NOS) has been found in cardiac tissue and in skeletal muscle from patients with chronic congestive heart failure (CHF). There have been few reports investigating NOS activity in other organs or in peripheral blood cells from patients with chronic CHF. To examine whether NOS activities in peripheral polymorphonuclear leukocytes (PML) are increased in patients with chronic CHF and to determine whether a correlation exists between disease severity and NOS activity in PML of patients with chronic CHF, we assessed the levels of NOS activity in PML by measuring the capacity of isolated PML to convert 3H-L-arginine to 3H-L-citrullin in 70 Japanese patients with chronic CHF and in 24 age-matched healthy volunteers. The levels of NOS activity in PML were significantly greater in patients with chronic CHF than in healthy volunteers (18.0 +/- 0.6% vs 11.5 +/- 0.3%, p <0.01). NOS activity in PML was increased with the severity of New York Heart Association functional class. Among the various neurohumonal factors, the plasma levels of interleukin-6, atrial natriuretic peptide, and norepinephrine showed independent and significant positive relations with levels of NOS activity in PML. Thus, we demonstrated that NOS activity in PML was elevated in patients with chronic CHF in relation to the severity of heart failure, circulating proinflammatory cytokines, and neurohormonal factors.

Adult↗
PubMed2001

Myocardial bridging of the left anterior descending coronary artery in acute inferior wall myocardial infarction.

BACKGROUND: We observed marked myocardial bridging of the left anterior descending coronary artery (LAD) in the acute stages of inferior wall myocardial infarction (MI) in a group of patients who developed shock despite successful reperfusion of the infarct-related lesion (IRL). HYPOTHESIS: The purpose of this study was to elucidate the clinical significance of myocardial bridging in patients with inferior wall MI and shock. METHODS: The study group consisted of 53 patients with single-vessel disease of the right coronary artery, who underwent coronary angiography for acute inferior wall MI. Clinical characteristics, coronary angiographic findings, and left ventricular function during the chronic phase were compared between the patients who developed shock (the shock group) and those who did not (the non-shock group). In addition, a multiple logistic analysis was performed to identify independent predictors of shock in patients with acute inferior wall MI. RESULTS: Reperfusion of the IRL was obtained in all 53 patients. The incidence of myocardial bridging of the LAD, the incidence of right ventricular MI, the peak creatine phosphokinase (CPK-MB). the pulmonary capillary wedge pressure, and the prevalence of pulmonary congestion seen on chest roentgenogram were significantly higher in the shock group than in the non-shock group. Myocardial bridging (p = 0.0018), right ventricular MI (p = 0.0374), and peak CPK-MB (p = 0.0189) were identified as independent predictors of shock in acute inferior wall MI. CONCLUSION: This study suggests that myocardial bridging plays a role in left ventricular function in the acute stage of inferior wall MI.

Adult↗
PubMed2001

Multidrug resistance gene (MDR-1) expression as a useful prognostic factor in patients with human hepatocellular carcinoma after surgical resection.

BACKGROUND: Multidrug resistance gene (MDR-1) overexpression has been correlated with tumor aggressiveness and worse prognosis in some human neoplasms. The aim of this study is to evaluate the clinical value of MDR-1 mRNA expression as a prognostic factor after surgical resection in human hepatocellular carcinoma (HCC). METHODS: MDR-1 mRNA levels in tissue samples from 34 patients with HCC, who underwent surgical resection, were measured by quantitative northern blot analysis. We stratified these patients into two groups according to a ratio of MDR-1 mRNA levels of HCC to nontumorous tissue; MDR-1 mRNA ratio > or = 1.0 and < 1.0. The overall and disease-free survival rates were analyzed using multivariate regression analysis. RESULTS: The median survival periods were 10.3 and 35.8 months for patients with the MDR-1 mRNA ratio > or = 1.0 and < 1.0, respectively, and the corresponding 5-year survival rates were 33 and 54%, respectively, P < 0.05. The multivariate analysis revealed that TNM stage and MDR-1 mRNA ratio were independent factors for predicting overall survival after surgical resection. CONCLUSION: This study suggested that the measurement of the MDR-1 mRNA levels in HCC and nontumorous liver tissue might be a useful prognostic factor after surgical resection in patients with HCC.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Diet and colorectal adenoma in Japanese males and females.

PURPOSE: The purpose of this study was to assess the relationship between risk of colorectal adenoma and dietary intake of nutrients and foods. METHODS: In 1992, diet was assessed by a semiquantitative food-frequency questionnaire in a cohort of the Takayama Study in Japan. Patients were 181 male and 98 female cohort members who were newly histologically proved to have colorectal adenoma at colonoscopic examination between January 1, 1993, and December 31, 1995. Controls were 12,607 males and 15,754 females who had no history of colorectal polyp, adenoma, and cancer at baseline (1992) and were not diagnosed to have these diseases during the follow-up period. RESULTS: In males, the risk of adenoma was significantly associated with intake of animal protein and vitamin A (relative risk, 1.42; 95 percent confidence interval, 1.00-2.04; and relative risk, 1.51; 95 percent confidence interval, 1.04-2.20, for the highest vs. lowest tertiles, respectively; P for trend = 0.048 and 0.03, respectively) after controlling for age, years of smoking, and alcohol intake. A significantly inverse association was observed for carbohydrate intake after controlling for the covariates (relative risk, 0.52; 95 percent confidence interval, 0.32-0.82, for the highest vs. lowest tertiles; P for trend = 0.02). Intakes of animal fat and cholesterol were marginally associated with risk of adenoma. CONCLUSION: Some dietary components such as animal protein and carbohydrate, which have been associated with risk of colorectal adenoma or cancer in western populations, were also associated with risk of colorectal adenoma in the Japanese population.

Adenoma↗
PubMed2001

Surgical treatment for a ruptured thoracic aortic aneurysm.

OBJECTIVE: The treatment for a ruptured thoracic aortic aneurysm remains controversial. This study was undertaken to assess the outcome from surgery. METHODS: Between 1993 and 1998, we have performed 19 operations for a ruptured thoracic aortic aneurysm. Patients with an impending rupture or a chronic false aneurysm were excluded. There were 11 men and 8 women, with a mean age of 70.5 +/- 6.7 years. The aneurysm was caused by dissection in 8 patients. Of these, 7 were acute (Stanford type A, 6; type B, 1), and the other one was chronic (type B). Aortic rupture occurred into the pericardial cavity (n = 7), into the left lung (n = 6), the mediastinum (n = 3), the pleural cavity (n = 2), or into the esophagus (n = 1). Severely unstable hemodynamics were noted in 12 patients with a rupture into the pericardium, mediastinum, or pleural cavity (Group A). Inotropic support was required in each of these patients. Metabolic acidosis developed all but 1 patient. The 7 patients with a rupture into the lung or esophagus coughed or vomited blood (Group B). The operative approach was anterior (n = 17) or lateral (n = 2). Grafts were placed in the ascending aorta (n = 4), ascending and transverse arch aorta (n = 7), transverse arch aorta (n = 3), or in the descending thoracic aorta (n = 5). Selective cerebral perfusion was used in 13 patients. RESULTS: There were 5 hospital deaths (26.3%). The postoperative complications included central nervous system dysfunction (n = 3), low cardiac output syndrome or cardiac arrhythmias (n = 3), respiratory failure (n = 4), acute renal failure (n = 1), and local or systemic infections (n = 4). The perioperative event-free rate was 36.8% overall, 25% in Group A, and 57.1% in Group B. CONCLUSIONS: Patients with unstable hemodynamics require prompt operative intervention. Rupture into the esophagus is associated with a high mortality rate. Rupture in a thoracic aortic aneurysm can be successfully treated with emergency surgery.

Aged↗
PubMed2001

Detection and management of concomitant coronary artery disease in patients undergoing thoracic aortic surgery.

OBJECTIVES: No method has been established to detect and manage coronary artery disease in patients undergoing thoracic aortic surgery. METHODS: Subjects were 192 patients scheduled for elective thoracic aortic surgery. Selection criteria for coronary angiography included a history of coronary artery disease or a positive dipyridamole myocardial perfusion imaging test. RESULTS: Four patients were inoperable due to complications associated with coronary angiography or aneurysm rupture following coronary revascularization. A total of 55 patients with coronary angiography (group A) underwent 57 thoracic aortic operations and 133 patients without coronary angiography (group B) underwent 143 similar operations. Of 13 group A patients with significant coronary stenosis, 9 underwent either preoperative percutaneous transluminal coronary angioplasty (n = 3) or concomitant coronary artery bypass (n = 6). Perioperative myocardial infarction occurred in 3 group A patients (5%) and in 4 group B patients (1%, ns). The incidence of cardiac events--perioperative myocardial infarction or cardiac death--in group A (11%, 6/57) was higher than that in group B (3%, 4/143; p < 0.05). Multivariate analysis demonstrated incomplete revascularization of major coronary arteries with significant stenosis as a risk factor for cardiac events (p = 0.0106). CONCLUSIONS: Although dipyridamole myocardial perfusion imaging was useful, additional selection criteria for coronary angiography is needed. Complete revascularization of major coronary arteries with significant stenosis is essential to reduce postoperative cardiac events.

Adolescent↗
PubMed2001

A new glucose-6-phosphate dehydrogenase variant G6PD Sugao (826C-->T) exhibiting chronic hemolytic anemia with episodes of hemolytic crisis immediately after birth.

A case of glucose-6-phosphate dehydrogenase (G6PD) deficiency associated with chronic hemolysis with episodes of hemolytic crisis immediately after birth is reported. The propositus was a 1-month-old Japanese male infant. Molecular analysis of the G6PD gene revealed a novel missense mutation (826C-->4T) in exon 8 predicting a single amino acid substitution, Pro276Ser. The mother was confirmed to be heterozygous for this mutation. We designated this novel class 1 variant as G6PD Sugao. Pro276 is a phylogenetically conserved residue that may play a significant role in dimer formation.

Anemia, Hemolytic, Congenital↗
PubMed2001

Myelodysplastic syndrome progresses rapidly into erythroleukemia associated with synchronous double cancers of the stomach and the papilla of Vater.

Patients with myelodysplastic syndrome (MDS) show a relatively high incidence of developing cancers. However, it is extremely rare that synchronous double cancers develop in an MDS patient. We report a case of MDS that progressed rapidly into erythroleukemia (M6 by French-American-British classification) complicated by gastric cancer and carcinoma of the papilla of Vater. A 66-year-old man was admitted because of pancytopenia with peripheral blasts. A diagnosis of MDS (with refractory anemia with excess of blasts in transformation [RAEB-T]) was made by bone marrow examination. Chromosome analysis revealed 46,XY. An early gastric cancer was also diagnosed by endoscopic examination. The peripheral blasts gradually proliferated and the disease progressed to M6. A chromosome abnormality 46,XY,del(1)(q42) was detected at the leukemic transformation. A CAG (low-dose cytarabine and aclarubicin in combination with granulocyte colony-stimulating factor) regimen was started as a remission-induction therapy. However, obstructive jaundice developed and a marked dilatation of bile ducts was observed by abdominal computed tomography (CT). A carcinoma of the papilla of Vater was detected by endoscopy. As remission was achieved and the pancytopenia improved, the patient subsequently underwent a surgical jejuno-choledochostomy to manage the jaundice. However, the leukemia relapsed thereafter and additional chromosome abnormalities including der(5)t(5;10)(p15:q11) were observed.

Aclarubicin↗
PubMed2001

Clinical significance of reverse redistribution on resting thallium-201 imaging in patients with vasospastic angina.

To evaluate the clinical significance of reverse redistribution (RR) of resting 201Tl single photon emission computed tomography (SPECT) in patients with vasospastic angina (VSA), we performed left ventriculography, coronary angiography and resting 201Tl-SPECT in 22 patients with VSA. Left ventriculography showed abnormal wall motion in 17 of 22 patients (77%) and 37 of 154 segments. Thirty-one of these 37 segments (84%) were within the area perfused by coronary arteries showing acetylcholine-induced vasospasm. On 201Tl images, abnormal findings were observed in 11 of 22 patients (50%), and among them, 7 patients (32%) had RR. Seven of 37 segments (19%) having abnormal regional wall motion had RR of 201TI, and in 6 of these 7 segments (86%), accumulation of 123I-BMIPP was found to be reduced. We conclude that repetitive brief myocardial ischemia may cause myocardial injuries in patients with VSA, and that the presence of RR of 201Tl indicates the presence of myocardial injury in these patients.

Acetylcholine↗
PubMed2001

Modelling and optimization of environmental conditions for kefiran production by Lactobacillus kefiranofaciens.

A mathematical model for kefiran production by Lactobacillus kefiranofaciens was established, in which the effects of pH, substrate and product on cell growth, exopolysaccharide formation and substrate assimilation were considered. The model gave a good representation both of the formation of exopolysaccharides (which are not only attached to cells but also released into the medium) and of the time courses of the production of galactose and glucose in the medium (which are produced and consumed by the cells). Since pH and both lactose and lactic acid concentrations differently affected production and growth activity, the model included the effects of pH and the concentrations of lactose and lactic acid. Based on the mathematical model, an optimal pH profile for the maximum production of kefiran in batch culture was obtained. In this study, a simplified optimization method was developed, in which the optimal pH profile was determined at a particular final fermentation time. This was based on the principle that, at a certain time, switching from the maximum specific growth rate to the critical one (which yields the maximum specific production rate) results in maximum production. Maximum kefiran production was obtained, which was 20% higher than that obtained in the constant-pH control fermentation. A genetic algorithm (GA) was also applied to obtain the optimal pH profile; and it was found that practically the same solution was obtained using the GA.

Algorithms↗
PubMed2001

Low density lipoprotein receptor mRNA in rat liver is affected by resistant starch of beans.

The effects of resistant starches of beans on serum cholesterol and hepatic low density lipoprotein (LDL) receptor mRNA in rats were investigated. Rats were fed a cholesterol-free diet with 150 g/kg corn starch (CS), 150 g/kg adzuki (Vigna angularis) starch (AS), 150 g/kg kintoki (Phaseolus vulgaris, variety) starch (KS), or 150 g/kg tebou (P. vulgaris, variety) starch (TS) for 4 wk. There were no significant differences in body weight among groups through the experimental period. The liver weight in the CS group was 1.1-1.2 times higher than that in the AS, KS, and TS groups. The cecum weight in the TS was 1.4 times higher than that in the CS group, and the cecal pH in the CS group was significantly higher than in the other groups. The serum total cholesterol, very low density lipoprotein + intermediate density lipoprotein + LDL-cholesterol and high density lipoprotein (HDL)-cholesterol concentrations in the bean starch groups were significantly lower than those in the CS group through the feeding period. The total cholesterol/HDL-cholesterol ratio in the bean starch groups was also significantly lower than that in the CS group at the end of the 4-wk feeding period. The hepatic cholesterol concentration in the TS group was significantly higher than in the CS group at the end of the 4-wk feeding period. The relative quantity of hepatic apo B mRNA in the AS group was 1.2 times higher than that in the CS group, and the hepatic LDL receptor mRNA levels in the AS and TS groups were 1.8-2.0 times higher than that in the CS group. The results of this study demonstrate that AS, KS, and TS lowered the serum total cholesterol level by enhancing the hepatic LDL receptor mRNA level.

Animals↗
PubMed2001

Expression and localization of a novel Rab small G protein (Rab38) in the rat lung.

The Rab small G protein family participates in intracellular vesicle transport, including exocytosis and endocytosis. The cDNA encoding a novel Rab-related small G protein (Rab38) has been cloned from rat lung cDNA library and recorded in GenBank (accession no. M94043). However, the expression and localization of the protein in the lung remains primarily unknown. We produced polyhistidine-tagged recombinant Rab38 and a polyclonal antibody with a synthetic peptide. Immunohistochemistry demonstrated that the protein is specifically localized in alveolar type II cells and in bronchial epithelial cells. In situ hybridization using a digoxygenin-labeled RNA riboprobe clearly showed that the mRNA of the protein is localized in alveolar type II cells and bronchial epithelial cells, especially terminal airway epithelial cells. Western blot and reverse transcriptase-polymerase chain reaction showed distinct expression of the protein and mRNA in isolated alveolar type II cells, but not in alveolar macrophages. The native protein was predominantly hydrophobic and was enriched in a high-density vesicle fraction but was barely detectable in nuclear and lamellar body fractions in alveolar type II cells. Immunofluorescence cytochemistry performed on cultured alveolar type II cells showed that Rab38 distributed extensively in the cytoplasm with a distribution pattern similar to endoplasmic reticulum rather than other subcellular organelles. These results suggest that this novel rab small G protein (Rab38) mediates vesicular transport in terminal airway epithelium.

Amino Acid Sequence↗
PubMed2001

Benefits and limits of hepatic resection for gastric metastases.

BACKGROUND: The significance of hepatic resection for gastric metastases has been controversial. METHODS: Forty consecutive patients undergoing hepatic resection for gastric metastases were reviewed to examine the benefits and the limits of hepatic resection using univariate and multivariate analyses. RESULTS: The overall survival was 27% at 2 years, 18% at 5 years, and 11% at 10 years. Six patients survived more than 5 years. All of the 6 patients underwent anatomical hepatic resection more extensive than segmentectomy, with sufficient resection margin. There were recurrences in 31 patients, and 94% of the recurrences were in the remaining liver. Univariate analysis showed time of hepatic metastases (P = 0.0078) and resection margin (P = 0.024) as significant prognostic factors. Multivariate analysis indicated that only time of hepatic metastases was an independent prognostic factor that influenced survival. CONCLUSIONS: These results suggest that in patients with synchronous metastases we should consider patient selection more strictly, and that in patients with metachronous metastases we should perform anatomical hepatic resection with sufficient resection margin.

Adult↗
PubMed2001

Degradation of human brain natriuretic peptide (BNP) by contact activation of blood coagulation system.

Brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) were added to venous blood samples from healthy volunteers, and incubated in tubes made of various materials. The residual immunoreactivity was measured with radioimmunoassay for BNP and ANP. In blood samples stored in glass tubes, immunoreactivity of ANP was more stable than that of BNP. In siliconized glass or PET tubes, however, BNP immunoreactivity was more stable than ANP. The activation of blood coagulation factors was evaluated from the kallikrein activity in plasma. Kallikrein activity was increased in plasma stored in glass tube while it was negligible in plasma stored in siliconized glass or PET tubes. In kaolin-activated plasma, more rapid BNP degradation and higher kallikrein activity were observed. Our results indicated that the blood coagulation factors, especially kallikrein, played an important role in digestion of BNP.

Blood Coagulation↗