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S Hatano

Publications and source records attributed to S Hatano.

At least 73 records · Page 4Linked to original sources
PubMed1991

A case-control study of lung cancer with special reference to asbestos exposure.

A case-control study of lung cancer was carried out in Yokosuka City, Kanagawa Prefecture, the location of a pre-war Japanese Imperial naval factory and present site of a U.S. naval base. Cytologically or pathologically confirmed male fatal cases of lung cancer during the period of 1978 to 1982 in Yokosuka Kyosai Hospital were compared with a control group in the same hospital. Controls who died from causes other than cancer, pneumoconiosis, accident, or suicide were matched by age to the cases. Information that included occupational and smoking history was obtained by interviews with the families of the 96 cases and 86 controls. Major results were as follows: a) The relative risks of lung cancer associated with asbestos exposure and suspected exposure were 2.41 (p less than 0.05) and 1.56, respectively, after controlling for age and smoking history, and the relative risk associated with smoking was 6.01 (p less than 0.05) after adjusting for age and asbestos exposure. b) The age- and smoking-adjusted relative risks of lung cancer associated with asbestos exposure were 3.40 (p less than 0.01) and 1.72 for Kreyberg groups I and II, respectively. Significantly elevated relative risk associated with smoking history was demonstrated for Kreyberg group I, but not for group II, after controlling for age and asbestos exposure.

Asbestos↗
PubMed1990

Primary structure of profilins from two species of Echinoidea and Physarum polycephalum.

Profilin is a small G-actin-binding protein, the amino acid sequence of which was previously reported for calf, human, Acanthamoeba and yeast. Here the amino acid sequences of three profilins obtained from eggs of two species of Echinoidea, Clypeaster japonicus (order, Clypeasteroida) and Anthocidaris crassispina (order, Echinoida), and plasmodium of Physarum polycephalum were determined. Two echinoid profilins were composed of 139 amino acid residues, N-termini were acylated and the molecular mass was calculated to be 14.6 kDa, slightly larger than that of 13 kDa estimated by SDS/PAGE [Mabuchi, I. & Hosoya, H. (1982) Biomed. Res. 3, 465-476]. On the other hand, Physarum profilin was composed of 124 amino acid residues, the N-terminus was acylated, and the calculated molecular mass was 13132 Da. The sequences of C. japonicus and A. crassispina profilins were homologous (84% identical). However, the similarity of these profilins with those form other organisms was low. The sequence of Physarum profilin was homologous with Acanthamoeba profilin isoforms (51% identical) and with yeast profilin (42% identical), but not with other profilins. The relatively conservative sequence of profilins from yeast, Physarum, Acanthamoeba, echinoid eggs and mammalian cells was found in the N-terminal region, which was suggested to be a common actin-binding region. The C-terminal region was also conserved, although to a lesser extent than the N-terminal region.

Amino Acid Sequence↗
PubMed1990

Control of actin filament length by phosphorylation of fragmin-actin complex.

Fragmin is a Ca2(+)-sensitive F-actin-severing protein purified from a slime mold, Physarum polycephalum (Hasegawa, T., S. Takahashi, H. Hayashi, and S. Hatano. 1980. Biochemistry. 19:2677-2683). It binds to G-actin to form a 1:1 fragmin/actin complex in the presence of micromolar free Ca2+. The complex nucleates actin polymerization and caps the barbed end of the short F-actin (Sugino, H., and S. Hatano. 1982. Cell Motil. 2:457-470). Subsequent removal of Ca2+, however, hardly dissociates the complex. This complex nucleates actin polymerization and caps the F-actin regardless of Ca2+ concentration. Here we report that this activity of fragmin-actin complex can be abolished by phosphorylation of actin of the complex. When crude extract from Physarum plasmodium was incubated with 5 mM ATP and 1 mM EGTA, the activities of the complex decreased to a great extent. The inactivation of the complex in the crude extract was not observed in the presence of Ca2+. In addition, the activities of the complex inactivated in the crude extract were restored under conditions suitable for phosphatase reactions. We purified factors that inactivated fragmin-actin complex from the crude extract. These factors phosphorylated actin of the complex, and the activities of the complex decreased with an increased level of phosphorylation of the complex. These factors, termed actin kinase, also inactivated the complex that capped the barbed end of short F-actin, leading to elongation of the short F-actin to long F-actin. Thus the length of F-actin can be controlled by phosphorylation of fragmin-actin complex by actin kinase.

Actin Cytoskeleton↗
PubMed1990

Improved fluorogenic assay for rapid detection of Vibrio parahaemolyticus in foods.

An improved fluorogenic assay for the rapid detection of Vibrio parahaemolyticus was developed. In the improved assay, the enrichment of V. parahaemolyticus was carried out in arabinose-glucuronate medium (0.5% arabinose, 0.25% glucuronate, 0.1% polypeptone, 0.1% yeast extract, 0.1% ammonium sulfate, 2% NaCl, 2 micrograms of polymyxin B sulfate per ml, pH 8.5) at 37 degrees C. After the cultivation, the trypsinlike activity of the bacteria was measured by fluorescence with the fluorogenic substrate benzoyl-L-arginine-7-aminomethylcoumarin. Even in the presence of 3 x 10(5) cells of Vibrio alginolyticus, 20 cells of V. parahaemolyticus were clearly detected after a 6-h enrichment cultivation by the assay. Fifty contaminated samples of 14 seafoods were examined for V. parahaemolyticus by the fluorogenic assay after enrichment cultivation for 6 or 8 h. The results were then compared with those obtained by the conventional bromothymol blue Teepol agar assay and the most-probable-number method. There was a linear relationship between trypsinlike activity measured by the assay and the number of V. parahaemolyticus cells in seafood as determined by the bromothymol blue Teepol agar and most-probable-number methods. Correlation coefficients were 0.95 and 0.93 after a 6-h cultivation and an 8-h cultivation, respectively. The presence of 10 cells of V. parahaemolyticus per gram of seafood sample was detected after a 10-h total detection time by the fluorogenic assay.

Animals↗
PubMed1990

[Factors predicting mortality in two years among the elderly at home in three different socioeconomic areas].

Random samples of elderly living at home aged 60 to 89 years old from 3 different socioeconomic areas, Shinagawa-ku in Tokyo, Shimizu city in Shizuoka Prefecture and central Tottori Prefecture, were interviewed between September 1984 and March 1985, regarding self-rated health related items. The sample comprising 3,580 persons was followed to the end of 1986 and survival status was studied. At follow up 434 subjects had died, and 67 had left the study areas. The purpose of this paper is to examine correlates of mortality after controlling for sex, age and activities of daily living (ADL). The main results were as follows: 1. Physical activity in work and/or leisure and its decline were strong influential factors in mortality. After controlling for age and ADL, mortality was not found to have a strong correlation to the presence of chronic disease. 2. The elderly who stopped smoking tobacco and/or drinking alcohol had a high mortality rate. This result was probably the result of a serious decline in physical health being the motive to stop smoking and drinking. 3. Self-rated health and subjective well-being were independent predictors of survival after controlling for age and ADL. Regional differences of self-rated health and subjective well-being were found, although these differences did not appear to produce regional differences in mortality. This indicates that subjective rating is not only a reflection of health status, but is also modified by psychosocial factors and that proxy use of subjective health status ratings in regional comparisons of health is problematic.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Factors affecting death at home in bedridden elderly people].

To examine factors which affect death at home in bedridden elderly people, relatives of bedridden elderly people, in three areas of Japan, who had died, were interviewed, and demographic, medical, social and familial factors were compared between 136 persons who died at home and 132 persons who died in the hospital. 1) In all three geographical areas, significantly more subjects who died at home had physicians who made home visits than in those who died at hospital (p less than 0.01). 2) The mean age at death was significantly higher in the elderly people who died at home than in those who died in the hospital in all three areas (p less than 0.01). 3) The results of multiple logistic regression analysis indicated that physician's home visits and death age were significantly related independently to death at home. This relation was independent of confounding factors such as residential area, disease type, or use of social services.

Age Factors↗
PubMed1989

Transient partial growth hormone deficiency due to zinc deficiency.

We present here a 13-year-old boy with partial growth hormone deficiency due to chronic mild zinc deficiency. When zinc administration was started, his growth rate, growth hormone levels, and plasma zinc concentrations increased significantly. His poor dietary intake resulted in chronic mild zinc deficiency, which in turn could be the cause of a further loss of appetite and growth retardation. There was also a possibility of renal zinc wasting which may have contributed to zinc deficiency. Zinc deficiency should be carefully ruled out in patients with growth retardation.

Adolescent↗
PubMed1989

A fragmin-like protein from plasmodium of Physarum polycephalum that severs F-actin and caps the barbed end of F-actin in a Ca2+-sensitive way.

Many protein factors regulating actin polymerization can be extracted from plasmodia of Physarum polycephalum in the presence of a high EGTA concentration (30 mM). A protein factor with the molecular weight of 60,000 (60 kDa protein) was especially interesting because of its fragmin-like properties. We purified and characterized this 60 kDa protein in the present study. The purified 60 kDa protein enhanced the initial rate of G-actin polymerization, severed F-actin, and capped the barbed end of F-actin in a Ca2+-dependent way. The threshold concentration for Ca2+ was around 10(-6) M. The flow birefringence measurement showed that the length of F-actin decreased from 2.8 to 1.0 microns depending on the concentration of 60 kDa protein added to F-actin. These properties were identical to those of fragmin (Mr 42,000) isolated from plasmodia (Hasegawa et al. (1980) Biochemistry 19, 2677-2683). However, the molecular weight, the tryptic peptide map, and the cross-reactivities with polyclonal anti-fragmin antibodies were different from those of fragmin. We concluded from these results that 60 kDa protein is a new Ca2+-sensitive F-actin-severing protein. Considering its similarity to fragmin, we termed the 60 kDa protein fragmin 60.

Actins↗
PubMed1989

Changing CHD mortality and its causes in Japan during 1955-1985.

Coronary heart disease (CHD) mortality has been decreasing continuously in all age-sex groups in Japan since 1976. An earlier increase in the 1950s was largely due to a change in the diagnostic method. Hypertension was a more important risk factor than hyperlipidaemia for ischaemic heart disease (IHD) in Japan. Increasing availability of a variety of foods supplying balanced nutrition, opportunities for health screening linked to detection and treatment of high blood pressure with little financial constraint, plus health insurance and health education have improved the cardiovascular health of the people, though these effects have not been evaluated objectively. These changes resulted in less advanced coronary atherosclerosis and less CHD despite a high frequency of smoking in men. Improving technology in the treatment of acute myocardial infarction (MI) may also have contributed to the decline in mortality.

Adult↗
PubMed1988

Purification of myxamoebal fragmin, and switching of myxamoebal fragmin to plasmodial fragmin during differentiation of Physarum polycephalum.

We have isolated and purified an activity from amoebae of Physarum polycephalum that reduces the flow birefringence of a solution of F-actin in a Ca2+-dependent manner. The purified activity from 100 g of amoebae consisted of 1 mg of a 40,000 mol. wt protein. DNase I-affinity chromatography demonstrated that the protein binds to Physarum actin in a Ca2+-dependent manner, and the binding is not reversed by excess EGTA. Viscometric measurement indicated that the protein (i) accelerates polymerization of G-actin, and (ii) severs F-actin, in a Ca2+-dependent manner. Thus, the protein appeared functionally similar to the fragmin previously isolated from Physarum plasmodia (plasmodial fragmin). However, the two proteins had slightly different mobilities on urea-SDS-PAGE, and antibodies raised against the two proteins scarcely cross-reacted with each other. Hence, we conclude that the two proteins are closely related to but are different from each other, and we have named the novel protein 'myxamoebal fragmin'. Immunoblot analysis indicated that myxamoebal and plasmodial fragmins are specifically present in amoebae and plasmodia, respectively. Results of immunofluorescence staining suggest that the synthesis of plasmodial fragmin is switched on coordinately with the synthesis of the heavy chain of plasmodial myosin and other plasmodium-specific contractile proteins during the apogamic differentiation of amoebae to plasmodia.

Actins↗
PubMed1987

Dynamic aspects of the contractile system in Physarum plasmodium. III. Cyclic contraction-relaxation of the plasmodial fragment in accordance with the generation-degeneration of cytoplasmic actomyosin fibrils.

Plasmodial fragments of Physarum polycephalum, excised from anterior regions of a thin-spread plasmodium, contracted-relaxed cyclicly with a period of 3-5 min. The area of the fragments decreased approximately 10% during contraction. In most cases, there was little endoplasmic streaming which indicates that contractions were synchronized throughout the fragment. By both polarized light and fluorescence microscopy, the organization and distribution of the cytoplasmic actomyosin fibrils in the fragments changed in synchrony with the contraction cycle. The fibrils formed during the contraction phase, and finally became a highly organized framework consisting of a three-dimensional network of numerous fibrils with many converging points (the nodes). During relaxation, the fibrils degenerated and disappeared almost completely, though some very weak fibrils remained near the nodes and the periphery. The results obtained by fluorometry of the fragments, stained with rhodamine-phalloidin, suggested that the G-F transformation of actin is not the main underlying process of the fibrillar formation.

Actomyosin↗
PubMed1986

Phosphorylation of Amoeba G-actin and its effect on actin polymerization.

Mass culture of Amoeba proteus enabled us to do biochemical studies on this organism. Actin and profilin were purified from Amoeba to examine actin phosphorylation and polymerization. The apparent molecular weight of Amoeba actin was 44,000, and its isoelectric point was 5.8. The apparent molecular weight of Amoeba profilin was 12,000, and its isoelectric point was 4.9. It reduced the rate of actin polymerization as reported in the cases of profilins from other organisms. A protein of Mr = 44,000 (44 K protein) was phosphorylated in a Ca2+-dependent manner in cell homogenate of Amoeba without being inhibited by calmodulin antagonists. Using the homogenate as a kinase, purified Amoeba G-actin could be phosphorylated in proportion to the amount of actin. However, neither Amoeba F-actin nor rabbit skeletal muscle G-actin was phosphorylated. The phosphorylation of Amoeba actin with a kinase partially purified from A. proteus increased with dilution of the actin concentration. When Amoeba profilin was added, more than 80% of the actin was phosphorylated. By viscometry, electron microscopy, and ultracentrifugation analysis it was demonstrated that Amoeba G-actin phosphorylated in the presence of profilin and kinase did not polymerize in this solution. High-performance liquid chromatography analysis showed that phosphorylated Amoeba actin remained in a monomeric state even under conditions favorable for actin polymerization.

Actins↗