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Biomedical subjects

K Yano

Publications and source records attributed to K Yano.

At least 325 records · Page 18Linked to original sources

Seroepidemiological study of Toxoplasma infection in central and western regions in Nepal.

The present study was carried out to ascertain the seroprevalence rate in different geographical areas in Central and Western Regions in Nepal. A total of 1,237 serum samples collected from Nuwakot (217), Kathmandu valley (402) and Chitawan (159) districts in Central Region, and Mustang (143), Surkhet (64) and Banke (252) districts in Western Region in Nepal were included in this study. Toxoplasma antibodies were detected by micro-latex agglutination (MLA) and enzyme linked immunosorbent assay (IgM-ELISA) methods. The seropositive rate in Central and Western Regions were found to be 48% and 49%, respectively; with an overall positive rate of 48 percent. Districtwise, the seropositive rate in Nuwakot, Kathmandu valley, Chitawan, Mustang, Surkhet and Banke districts were 38, 46, 64, 51, 67 and 44%, respectively. Interestingly, the relatively newly inhabited Surkhet district in Western Region and Chitawan district in Central Region showed significantly higher seropositive rate compared with those of two other districts in the respective Regions (p < 0.05). Ethnically, Tibeto-Burmans showed higher seropositive rates in Central Region (p > 0.05). In contrast, Indo-Aryans showed higher seropositive rate in Western Region (p > 0.05). Age related increase in seropositivity was observed only in Central Region. One percent of Toxoplasma antibody positive samples also showed Toxoplasma IgM antibody positivity.

Adult↗

Low serum cholesterol and mortality. Which is the cause and which is the effect?

BACKGROUND: Many studies have reported an association between a low or lowered blood total cholesterol (TC) level and subsequent nonatherosclerotic disease incidence or death. The question of whether low TC is a true risk factor or alternatively a consequence of occult disease at the time of TC measurement remains unsettled. To shed new light onto this problem, we analyzed TC change over a 6- year period (from exam 1 in 1965 through 1968 to exam 3 in 1971 through 1974) in relation to subsequent 16-year mortality in a cohort of Japanese American men. METHODS AND RESULTS: The study was based on 5941 men 45 to 68 years of age without prior history of coronary heart disease, stroke, cancer, or gastrointestinal-liver disease at exam 1 who also participated in exam 3 of the Honolulu Heart Program. The association of TC change with mortality end points was investigated with two different approaches (continuous and categorical TC change) with standard survival analysis techniques. Falling TC level was accompanied by a subsequent increased risk of death caused by some cancers (hemopoietic, esophageal, and prostate), noncardiovascular noncancer causes (particularly liver disease), and all causes. The risk-factor-adjusted rate of all-cause mortality was 30% higher (relative risk, 1.30; 95% CI, 1.06 to 1.59) among persons with a decline from middle (180 to 239 mg/dL) to low (< 180 mg/dL) TC than in persons remaining at a stable middle level. By contrast, there was no significant increase in all-cause mortality risk among cohort men with stable low TC levels. Nonillness mortality (deaths caused by trauma and suicide) was not related to either TC change or the average of TC levels in exams 1 and 3. CONCLUSIONS: These results add strength to the reverse-causality proposition that catabolic diseases cause TC to decrease.

Aged↗

Amino acid sequence of spinach ferredoxin:thioredoxin reductase catalytic subunit and identification of thiol groups constituting a redox-active disulfide and a [4Fe-4S] cluster.

Ferredoxin:thioredoxin reductase is a [4Fe-4S] protein involved in the light regulation of carbon metabolism in oxygenic photosynthesis. This enzyme catalyses the reduction of thioredoxins with light-generated electrons. Ferredoxin:thioredoxin reductase is composed of two dissimilar subunits, a catalytic subunit, and a variable subunit. The catalytic subunit of spinach ferredoxin:thioredoxin reductase, which contains the redox-active disulfide bridge, was sequenced by conventional protein sequencing techniques and the functional roles of all eight cysteine residues were examined by chemical modifications. The polypeptide chain with a calculated molecular mass of 12,959 Da consists of 113 amino acids and has a calculated isoelectric point of 5.30. Six of the eight cysteine residues are clustered as Cys-Pro-Cys and Cys-His-Cys groups. Cys19 and Cys27 are free cysteines with no catalytic function, Cys54 and Cys84 constitute the redox-active disulfide bridge of the active site, and the remaining four, Cys52, Cys71, Cys73, and Cys82 bind the Fe-S cluster.

Amino Acid Sequence↗

Sudden death, impaired glucose tolerance, and diabetes in Japanese American men.

BACKGROUND: Diabetes and glucose intolerance have been shown to increase the risk of cardiovascular mortality in a number of different populations. Most studies have been based on short follow-up periods, and few have had sufficient numbers to allow researchers to look at sudden death as an outcome. METHODS AND RESULTS: The relation of sudden death, defined as unexpected death occurring within either 1 or 24 hours of first symptoms, to glucose intolerance measured by a nonfasting 1-hour postload measurement made in 1965 or history of diabetes was examined by use of 23 years of follow-up on the 8006 participants enrolled in the Honolulu Heart Program. After adjustment for baseline body mass index, hypertension, cholesterol, triglycerides, smoking, alcohol consumption, and left ventricular hypertrophy or strain, the relative risks for sudden death within 24 hours in individuals with high-normal (151 to 224 mg/dL), asymptomatic high glucose values (> or = 225 mg/dL), and diabetes compared with those with lower glucose values (< 151 mg/dL) were 1.59, 2.22, and 2.76, respectively. All these relative risks were statistically significant (P < or = .05). Trends for sudden death in 1 hour were similar. Among men with sudden death < 1 hour after onset of symptoms, the strength of the association between diabetes and sudden death was stronger among those classified as having died of unknown causes who thus were more likely to have died of an arrhythmia than among those classified as having died of coronary heart disease. CONCLUSIONS: The relations seen in these analyses indicate that individuals with glucose intolerance or diagnosed diabetes are at increased risk for sudden death.

Aged↗

Replication factor encoded by a putative oncogene, set, associated with myeloid leukemogenesis.

DNA replication of the adenovirus genome complexed with viral core proteins is dependent on the host factor designated template activating factor I (TAF-I) in addition to factors required for replication of the naked genome. Recently, we have purified TAF-I as 39- and 41-kDa polypeptides from HeLa cells. Here we describe the cloning of two human cDNAs encoding TAF-I. Nucleotide sequence analysis revealed that the 39-kDa polypeptide corresponds to the protein encoded by the set gene, which is the part of the putative oncogene associated with acute undifferentiated leukemia when translocated to the can gene. The 41-kDa protein contains the same amino acid sequence as the 39-kDa protein except that short N-terminal regions differ in both proteins. Recombinant proteins, which were purified from extracts of Escherichia coli, expressing the proteins from cloned cDNAs, possessed TAF-I activities in the in vitro replication assay. A particular feature of TAF-I proteins is the presence of a long acidic tail in the C-terminal region, which is thought to be an essential part of the SET-CAN fusion protein. Studies with mutant TAF-I proteins devoid of this acidic region indicated that the acidic region is essential for TAF-I activity.

Amino Acid Sequence↗

Lifestyle and biologic factors associated with atherosclerotic disease in middle-aged men. 20-year findings from the Honolulu Heart Program.

OBJECTIVES: To examine the association between a variety of baseline lifestyle and biologic factors in a middle-aged cohort of Japanese-American men and the 20-year incidence rates of total atherosclerotic end points and each of the initial clinical manifestations of this disease, including fatal and nonfatal coronary heart disease, angina pectoris, thromboembolic strokes, and aortic aneurysms. DESIGN: Prospective epidemiologic study. POPULATION: Japanese-American men (N = 2710) between the ages of 55 and 64 years at the time of the initial clinical examination of the Honolulu Heart Program (1965 through 1968) free from evidence of coronary heart disease, cerebrovascular disease, cancer, or aortic aneurysms. RESULTS: Among the men studied, 602 atherosclerotic events developed during the 23-year period of follow-up (1965 through 1988). After adjustment for each of the baseline characteristics examined, significant positive associations between quartile cutoffs of body mass index, systolic blood pressure, serum levels of cholesterol, triglycerides, glucose, and uric acid, as well as cigarette smoking, and the occurrence of any atherosclerotic end point were seen, while an inverse association with alcohol consumption was observed. Characteristics associated with the development of other fatal and nonfatal clinical events in this cohort, including coronary heart disease, thromboembolic stroke, and aortic aneurysms are presented with accompanying relative and attributable risks. CONCLUSIONS: The results of this prospective epidemiologic study provide insights to the long-term predictive utility of the commonly accepted risk factors for coronary heart disease in relation to the different clinical manifestations of atherosclerosis in a middle-aged male cohort followed up for approximately 20 years. These results provide additional support for risk factor modification in middle-aged men and for the encouragement of positive long-term lifestyle changes.

Arteriosclerosis↗

Physical activity and incidence of diabetes: the Honolulu Heart Program.

Few prospective studies have assessed the relation between physical activity and diabetes. The authors examined this relation prospectively among 6,815 Japanese-American men in the Honolulu Heart Program who were aged 45-68 years and initially free of diagnosed diabetes in 1965-1968. A physical activity index was calculated based on time spent per day in different activity levels and a weighting factor correlated with estimated oxygen consumption. Incidence of clinically recognized diabetes was based on self-reported use of diabetic medication at one of two subsequent examinations. The age-adjusted 6-year cumulative incidence of diabetes decreased progressively with increasing quintile of physical activity from 73.8 to 34.3 per 1,000 (p < 0.0001, trend) in all men and from 53.9 to 21.7 per 1,000 (p < 0.0001, trend) among men with a non-fasting glucose level < 225 mg/dl one hour after a 50-gm load, the latter group being less likely to have unrecognized diabetes at baseline. When stratified by tertile of baseline glucose, trends in incidence across physical activity quintiles were statistically significant in the low and middle tertiles but not in the high tertile. Similar inverse trends were observed for men in the lower four quintiles of body mass index, however, these trends were weaker and not significant for men in the upper quintile of body mass index. Age-adjusted odds ratios for diabetes comparing the upper with the lower four quintiles of physical activity were 0.55 (95% confidence interval (CI) 0.41-0.75) for all men and 0.50 (95% CI 0.33-0.74) for men with glucose < 225 mg/dl. After adjustment for age, body mass index, subscapular/triceps skinfold ratio, systolic blood pressure, triglycerides, glucose, hematocrit, and parental history of diabetes, odds ratios were still statistically significant and similar in magnitude. Restriction of analyses to men who remained free of cardiovascular disease during the study period produced similar results, which suggests that inactivity due to subclinical cardiovascular disease is unlikely to be responsible for these findings. Risk factor-adjusted odds ratios for older men (55-68 years) demonstrated that physical activity confers at least the same degree of protection as in younger men (45-54 years). These results indicate that physical activity is associated inversely with incident diabetes and that the beneficial effect does not appear to be mediated through improvements in other risk factors assessed in this study.

Age Factors↗

Relationship between peritoneal collagen type IV concentrations and the presence of disseminated metastases in gastric cancer.

OBJECTIVE: To predict disseminated microscopic foci or occult micrometastases in the peritoneal cavity in patients with gastric cancer. DESIGN: Randomly selected patients with gastric cancer had peritoneal washings performed at the beginning of laparotomy. PATIENTS: Thirty-nine patients with gastric carcinoma and 10 patients with other benign disease as a control group. SETTING: Inpatients in a surgical department. INTERVENTIONS: The concentration of collagen type IV in the irrigated peritoneal fluid was measured radioimmunologically. Intraoperative peritoneal cytologic examination and measurements of carcinoembryonic antigen (CEA) levels were also performed. MAIN OUTCOME MEASUREMENTS: Results of the quantitative analyses of the collagen type IV concentrations as related to the clinicopathological characteristics and comparison of these results with regard to those of the peritoneal cytologic examination and CEA and collagen type IV levels. RESULTS: There were eight patients with elevated collagen type IV concentrations. They had carcinomas with serosal invasion (pT3 and pT4) and metastatic spread (pN2, M1). Patients with clinically evident peritoneal disseminated metastases had significantly higher collagen type IV concentrations compared with those without metastases. The collagen type IV levels were more sensitive than peritoneal cytologic examination or CEA values in detecting disseminated metastases. There was an early peritoneal recurrence in the form of ovarian metastases in one patient with negative cytologic results and an elevated collagen type IV level. Linear regression analysis showed a statistically significant correlation between the collagen type IV and CEA levels. CONCLUSION: Quantitative detection of abnormal collagen type IV levels may be useful for predicting the presence of disseminated metastases in patients with gastric cancer.

Adult↗

Sustained release of basic fibroblast growth factor from the synthetic vascular prosthesis using hydroxypropylchitosan acetate.

We designed a model vascular prosthesis consisting of expanded polytetrafluoroethylene (Gore Tex) loaded with basic fibroblast growth factor (bFGF), and studied its in vivo bFGF release behavior. To control the release rate of bFGF, biodegradable hydroxypropylchitosan acetate (HPCHA) was also incorporated into the Gore Tex disks with bFGF. HPCHA was dissolved in bFGF solution (180 micrograms/ml) at a concentration of 4% (wt/vol). A Gore Tex tube was cut into a length of about 5 cm and one end was sealed with a vascular clamp. The tube was then filled with resulting solution under appropriate pressure until the solvents seeped through the pores. The tube loaded with bFGF solution was freeze-dried and was cut into disks (0.75 cm in diameter). bFGF content in a HPCHA-free Gore disk was 2.05 +/- 0.32 micrograms (SE, n = 5). bFGF content in a HPCHA Gore disk was 2.71 +/- 0.41 micrograms (SE, n = 5). In an in vivo study in which the bFGF loaded Gore Tex disk was implanted in rabbit skin pockets, almost 100% of bFGF from HPCHA-free disks was released within 24 h, whereas some 60% remained after 24 h in the HPCHA-loaded disks. HPCHA is a useful biodegradable carrier for controlling the release rate of the drug from the synthetic vascular prosthesis.

Animals↗