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Biomedical subjects

S Hatano

Publications and source records attributed to S Hatano.

At least 55 records · Page 3Linked to original sources
PubMed1996

p53 mutations in two patients with intraductal papillary adenoma of the pancreas.

There has been no report on p53 gene mutation in benign human pancreatic intraductal tumors. We examined pancreatic juice and tissue specimens from two patients with intraductal papillary adenoma of the pancreas by polymerase chain reaction-single-strand conformation polymorphism analysis and direct sequencing and found point mutations of p53 gene resulting in amino acid substitutions in exons 6 and 8. Thus, p53 gene mutation may be an early event in the neoplastic process of some pancreatic intraductal tumors and may play an important role in tumorigenesis.

Adenoma↗
PubMed1996

Impairment of the glycolytic system and actin in baker's yeast during frozen storage.

After frozen storage for 7 d, the viability and CO2 productivity of a conventional baker's yeast strain D greatly decreased. The viability of a freeze-tolerant strain, DFT, used for the frozen dough method slightly decreased after the same storage period, while the CO2 productivity greatly decreased. The CO2 productivity and DNase I inhibitory activity of actin of the cell-free extracts prepared immediately after thawing from 7-d frozen-stored cells markedly decreased in both strains. In DFT, however, the productivity and the inhibitory activity of the cell-free extract increased when the extract was prepared after incubation of the frozen-thawed cells at 30 degrees C. The increase in the inhibitory activity first occurred and then the increase in the CO2 productivity. Gel filtration patterns of actin and glycolytic enzymes were compared between cell-free extracts of both strains. Peaks of actin and activity peaks of hexokinase and pyruvate kinase decreased in the strain D after frozen storage, but only slightly in the strain DFT. After frozen storage, phosphofructokinase activity peak shifted to a lower molecular weight in strain D.

Actins↗
PubMed1996

Cholesterol levels among Japanese Americans and other populations: Seattle Nikkei Health Study.

The purpose of this study was to compare average cholesterol levels between Seattle based Japanese Americans and three other populations: U.S. population, native Japanese population and native Japanese urban workers. A total of 1,466 Japanese Americans (724 men and 742 women) participated in cardiovascular disease screening in the Seattle area during 1989 94. Data sources for comparisons are from the Third National Health and Nutrition Examination Survey for 1988-91, the results of the National Cardiovascular Disease Examination Survey in Japan for 1990, and cardiovascular disease screening conducted by the Epidemiological Arteriosclerosis Research Institute in Japan for 1989. Total cholesterol and triglyceride levels of Seattle Japanese American men and women were highest among the four populations. Among men, high density lipoprotein cholesterol (HDL-C) levels for Seattle Japanese Americans and native Japanese were similar and fell between those of urban Japanese workers and the U.S. population. In women, the average HDL C levels were highest in the Japanese urban workers, second highest in Seattle Japanese Americans, and lowest in both the U.S. population and native Japanese population. These differences in lipid levels may be caused by both genetic and environmental factors, which are now under investigation.

Adult↗
PubMed1995

Identification of DNA-binding proteins changed after induction of sporulation in Bacillus cereus.

DNA-binding proteins were extracted from both exponentially growing cells of Bacillus cereus ts-4 and cells that were induced to sporulate at different stages of chromosome replication, by using a double-stranded B. cereus ts-4 DNA-cellulose column. Two-dimensional electrophoresis of the proteins found that the amounts of 17 proteins changed drastically after induction of sporulation at all the stages. For 8 of those proteins, the largest or the smallest amount was found in the cells which were induced to sporulate 40 min after the initiation of chromosome replication, the sensitive stage for sporulation. The N-terminal amino acids of 6 proteins among the selected proteins were sequenced. The sequence obtained from a 59-kDa protein had sequence similarity (> 45%) to GroEL from several bacterial species. In addition, the sequences from 76- and 52-kDa proteins matched deduced amino acid sequences of a Mycobacterium leprae gene showing homology to the bacteria atp operon and the B. subtilis guaB for IMP dehydrogenase, respectively.

Amino Acid Sequence↗
PubMed1995

Effect of tea polyphenols on fecal flora and fecal metabolic products of pigs.

The effects of tea polyphenols on fecal flora and fecal metabolic activities were studied in eight 30-day-old pigs fed a basal diet (control) or the diet supplemented with 0.2% of tea polyphenols for 2 weeks. During tea polyphenol administration compared to before administration, the levels of lactobacilli were increased significantly (P < 0.05 and P < 0.01 on days 7 and 14 of administration, respectively), whereas the levels of total bacteria (P < 0.01) and bacteroidaceae (P < 0.01 and P < 0.001 on days 7 and 14 of administration, respectively) were decreased significantly. The detection rate of lecithinase positive clostridia including Clostridium perfrigens showed a tendency to decrease during administration. No detectable change occurred in the levels of other organisms throughout the experimental period. Fecal concentrations of ammonia were decreased significantly (P < 0.05 and P < 0.01 on days 7 and 14 of administration, respectively). Fecal phenol (P < 0.001), p-cresol (P < 0.05), and skatol (P < 0.01) were reduced significantly on day 14 of administration compared to before administration. The amounts of fecal short chain fatty acids, acetic acid (P < 0.05) and lactic acid (P < 0.05) were increased significantly on day 14 of administration. The pH values were decreased slightly during administration. The odour of the feces was reduced remarkably during tea polyphenol administration.

Animals↗
PubMed1995

[A case of multiple liver metastasis from ileac carcinoid effectively treated with continuous intraarterial infusion of somatostatin analog].

We report a case of multiple liver metastasis from ileac carcinoid treated with continuous intraarterial infusion of somatostatin analog. A 65-year-old man who complained of chest pain was admitted to Yamaguchi University Hospital School of Medicine for further examination of cardiac angina. Liver tumors, which were detected during ECHO cardiogram examination, were diagnosed as metastasis from carcinoid by percutaneous transhepatic liver biopsy. Primary tumor was found at the ileum by colonofiberscopy. We performed ileo-cecal resection and catheterization from the gastroduodenal artery for intraarterial chemotherapy under laparotomy. After the operation, the patient was treated with continuous intraarterial infusion of somatostatin analog (100 micrograms/day, 5 days/week for 16 weeks). The tumor in segment 6 (S6) disappeared, but the tumor in S2 enlarged after the therapy. Hepatic angiography confirming the drug distribution demonstrated the occlusion of the left hepatic artery. This drug was thus distributed to the tumor in S6 but not in S2. These results suggest that somatostatin analog may have a direct anti-tumor effect. Furthermore, no side effect was observed. Thus, intraarterial infusion of somatostatin analog may be a useful therapy for liver metastasis from carcinoid.

Aged↗
PubMed1995

Molecular cloning and expression of hardening-induced genes in Chlorella vulgaris C-27: the most abundant clone encodes a late embryogenesis abundant protein.

To investigate the effects of hardening on gene expression in Chlorella vulgaris Beijerink IAM C-27 (formerly Chlorella ellipsoidea Gerneck IAM C-27), a frost-hardy strain, 17 cDNA clones corresponding to hardening-induced Chlorella (hiC) genes were isolated by differential screening of a cDNA library from 6-h hardened cells. Northern blot analysis of transcripts of hiC genes showed that these genes are specifically induced by hardening and that their patterns of induction vary. Southern blots of genomic DNAs from two strains (Chlorella ellipsoidea Gerneck IAM C-102, chilling-sensitive; and C. vulgaris C-27, frost-hardy) of Chlorella indicated that ten hiC clones out of 17 hybridized only with DNA of strain C-27 and the other seven clones hybridized with DNA of both strains. However, of these seven clones, transcripts corresponding to six clones did not accumulate in strain C-102 at low temperatures. The sequence of a deduced protein encoded by the most abundant clone, hiC6, exhibited homology to sequences of Group III LEA (late embryogenesis abundant) proteins and had an amino-terminal amino acid sequence that was similar to the sequences of chloroplast transit peptides.

Acclimatization↗
PubMed1995

Isolation and characterization of hardening-induced proteins in Chlorella vulgaris C-27: identification of late embryogenesis abundant proteins.

Hardening-induced soluble proteins of Chlorella vulgaris Beijerink IAM C-27 (formerly Chlorella ellipsoidea Gerneck IAM C-27) were isolated and purified by two-dimensional high-performance liquid chromatography (2D-HPLC) on an anion-exchange column, with subsequent reversed-phase chromatography. Some of the proteins were resolved by SDS-PAGE, characterized by amino-terminal sequencing and identified by searching for homologies in databases. Separation of the soluble proteins during the hardening of Chlorella by a combination of 2D-HPLC and SDS-PAGE revealed that at least 31 proteins were induced or increased in abundance. Of particular interest was the induction after 12 h of a 10-kDa protein with the amino-terminal amino acid sequence AGNKPITEQISDAVGAAGQKVG and the induction after 6 h of a 14-kDa protein with the amino-terminal sequence ALGEESLGDKAKNAFEDAKDAVKDAAGNVKEAV. The amino-terminal sequences of these proteins indicated that they were homologous to late embryogenesis abundant (LEA) proteins. Furthermore, the level of a 22-kDa protein also increased after 12 h. The amino-terminal sequence of this protein, AAPLVGGPAPDFTAAAVFD, indicated that it was homologous to thioredoxin peroxidase.

Amino Acid Sequence↗
PubMed1993

A simplified two-time-point method for measuring whole-body protein synthesis in chicken embryos cultured in vitro: response to fragmented bovine growth hormone.

1. A simplified two-time-point method for measuring whole-body protein synthesis of chicken embryos cultured in vitro was developed. 2. The chicken embryos at 7 days of egg incubation age were cultured with a synthetic medium containing L-[4-3H]phenylalanine in a rotatory whole-embryo culture apparatus for a period of up to 60 min. 3. An adequate combination of measurement time points was examined by comparing fractional synthesis rates calculated by the simplified two-time-point method with those estimated by a full curve-fitting method which would give best estimates. The effect of fragmented bovine growth hormone added to the culture medium on fractional synthesis rates was also tested. 4. The results indicated that the closest fractional synthesis rates by the simplified two-time-point method to the one by the full curve-fitting method were obtained by taking the time points of t1 at 10 min and t2 at 30 or 60 min with intraperitoneal injection of the tracer prior to the culture period. 5. With the simplified two-time-point method, the fragmentation of bovine growth hormone was shown to increase the biopotency in inducing fractional synthesis rates approximately 100 times as high as that of the intact growth hormone. 6. It was concluded, therefore, that the present assay method would be convenient and sensitive for searching physiologically active compounds in promoting growth and protein synthesis in the chicken.

Animals↗
PubMed1993

[Social and health conditions in a former coal mining area in Fukuoka, Japan].

The purpose of this study was to evaluate the residual effect of the former coal mining industry upon the social and health conditions of an area that was the side of a once prospering coal mining industry. The area was partitioned into two types of districts according to the percentage of residential housing that was for coal miners. The first district consisted predominantly of tenant homes for the coal miners (coal miner district) and the remaining area made up the second district (other district). Health conditions in the two districts were compared by standard mortality rates (SMR), and age-specific death rates for all disease and non-disease related deaths. Social conditions were compared based upon sex, age, employment stauts, and job type. The results were as follows: (1) Total unemployment rate, the percentage of households with no income earner, and single-family households, was higher in the coal miner district than in the other district. (2) The SMRs for all deaths in the coal miner district were significantly higher than in the other district. (3) While not significant the SMRs for disease related deaths were higher in the coal miner district. (4) Even in the younger age group (both male and female), while having no direct relationship with the coal mining industry, the SMRs were higher in the coal mine district. (5) The SMRs for suicides and homicides that occurred among the men residing in the coal miner district were higher. In conclusion, the social and health conditions in this former coal mining residential area were poorer than in the other area.

Adolescent↗
PubMed1992

Identification of actin kinase activity in purified fragmin-actin complex.

Actin kinase phosphorylates actin of fragmin-actin complex, resulting in the inactivation of the nucleation and capping activities of the complex. Fragmin-actin complex was prepared by a new purification procedure. Incubation with ATP caused inactivation of the purified complex and phosphorylation of actin of fragmin-actin complex. The detailed analysis of the complex by SDS-gel electrophoresis showed that actin kinase was co-purified with the fragmin-actin complex. Formation of such an association between actin kinase and substrate suggests that the kinase is localized on the fragmin-actin complex to efficiently regulate actin cytoskeletons.

Actins↗
PubMed1992

Requirement of phosphatidylinositol 4,5-bisphosphate for alpha-actinin function.

Inositol phospholipid turnover is enhanced during mitogenic stimulation of cells by growth factors and the breakdown of phosphatidylinositol 4,5-bisphosphate (PtdInsP2) may be important in triggering cell proliferation. PtdInsP2 also binds actin-binding proteins to regulate their activity, but it is not yet understood how this control is achieved. The protein alpha-actinin from striated muscle contains large amounts of endogenous PtdInsP2, whereas that from smooth muscle has only a little but will bind exogenously added PtdInsP2. In vitro alpha-actinin binds to F-actin and will crosslink actin filaments, increasing the viscosity of F-actin solutions. We report here that alpha-actinin from striated muscle is an endogenous PtdInsP2-bound protein and that the specific interaction between alpha-actinin and PtdInsP2 regulates the F-actin-gelating activity of alpha-actinin. Although the F-actin-gelating activity of alpha-actinin from smooth muscle is much reduced compared with that from striated muscle, exogenous PtdInsP2 can enhance the activity of smooth muscle alpha-actinin to the level seen in striated muscles. These results show that PtdInsP2 is present in striated muscle alpha-actinin and that it is necessary for alpha-actinin to realize its maximum gelating activity.

Actinin↗
PubMed1992

Inositol phospholipid-induced suppression of F-actin-gelating activity of smooth muscle filamin.

Filamin, a high molecular weight actin-binding protein, cross-links actin filaments and produces a gel composed of F-actin. The effects of polyphosphoinositides on the gelating activity of smooth muscle filamin were examined by measuring the low shear viscosity of the F-actin solutions containing filamin incubated with phosphatidylinositol (PI), phosphatidylinositol 4-monophosphate (PIP), or phosphatidylinositol 4,5-bisphosphate (PIP2). Micelles of these inositol phospholipids bound to filamin inhibited the ability to form a gel of F-actin. The inhibiting activity of each phospholipid was in the following order, PIP2 greater than PIP greater than PI. The F-actin binding assay of filamin revealed that the inhibition of F-actin-gelation resulted in the loss of the F-actin-binding activity of filamin. Thus, polyphosphoinositides may play important roles in regulating the gelating activity of filamin.

Actins↗
PubMed1992

Phosphorylation by actin kinase of the pointed end domain on the actin molecule.

Fragmin from plasmodium of Physarum polycephalum binds G-actin and severs F-actin in the presence of Ca2+ over 10(-6) M. The fragmin-actin complex consisting of fragmin and G-actin nucleates actin polymerization and caps the barbed (fast growing) end of F-actin, regardless of the concentrations of Ca2+, and the actin filaments are shortened. Actin kinase purified from plasmodium abolishes the nucleation and capping activities of the complex by phosphorylating actin of the fragmin-actin complex (Furuhashi, K., and Hatano, S. (1990) J. Cell. Biol. 111, 1081-1087). This inactivation of the complex leads to production of long actin filaments. We obtained evidence that Physarum actin is phosphorylated by actin kinase at Thr-201, and probably at Thr-202 and/or Thr-203, with 1 mol of phosphate distributed among them. This finding raises the possibility that the site of phosphorylation, Thr-201 to Thr-203, is positioned on the pointed (slow growing) end domain of the actin molecule, because growth of actin filaments from the fragmin-actin complex occurs only from the pointed end. These observations are consistent with a model of the three-dimensional structure of G-actin. Inactivation of the fragmen-actin complex may follow phosphorylation of the pointed end domain of actin.

Actins↗
PubMed1992

Actin kinase: a protein kinase that phosphorylates actin of fragmin-actin complex.

Actin of fragmin-actin complex is phosphorylated by an endogenous kinase from plasmodium of Physarum polycephalum. The phosphorylation abolishes the nucleation and capping activities of fragmin-actin complex. The kinase has been purified and termed actin kinase [Furuhashi, K. & Hatano, S. (1990) J. Cell Biol. 111, 1081-1087]. Enzymatic properties of the purified actin kinase were studied in detail. Actin kinase exhibited the highest activity under conditions physiological for the plasmodium (30 mM KCl, 6 mM MgCl2, pH 7.0). The Vmax and the Km of the enzyme for ATP were about 83 mumol/min/mg and 25 microM, respectively. The Km for fragmin-actin complex was 190 nM. The purified actin kinase phosphorylated actin of fragmin-actin complex at a constant rate regardless of Ca2+ concentration. Similarly, 2 microM cAMP, 2 microM cGMP, 2 micrograms/ml calmodulin in the presence of Ca2+ or 1 mM GTP showed no effect on the activity of the purified enzyme. Actin kinase did not phosphorylate histone H1, H2B, alpha-casein, or beta-casein, suggesting that actin kinase is a new kind of protein kinase which specifically phosphorylates actin of the fragmin-actin complex.

Actins↗
PubMed1991

F-actin bundling protein from Physarum polycephalum: purification and its capacity for co-bundling of actin filaments and microtubules.

An F-actin bundling protein was isolated and purified from plasmodium of Physarum polycephalum. The F-actin bundling protein in Physarum extract was passed through a DEAE-cellulose column. After the protein in the fraction was treated with 6 M urea, it was purified by gel filtration on Sephacryl S-300 HR followed by chromatography on CM-Toyopearl (cation exchange) in the presence of 6 M urea. The purified protein gave a single band on SDS-PAGE, and the molecular weight was estimated to be 52,000. This F-actin bundling protein is referred to as the 52 kDa protein. Interestingly, the 52 kDa protein also induced bundling of microtubules. The formation of F-actin and microtubule bundles was Ca(2+)-insensitive, but depended on the salt concentration. Each bundle formed at NaCl concentrations less than 0.1 M. The 52 kDa protein cross-reacted with monoclonal antibody raised against a HeLa 55 kDa protein (an F-actin bundling protein from HeLa cells) (Yamashiro-Matsumura and Matsumura: J. Biol. Chem. 260:5087-5097, 1985). When the 52 kDa protein was added to a mixture of actin filaments and microtubules, co-bundles composed of both filaments formed. This is the first reported example in which an F-actin bundling protein induced co-bundling of actin filaments and microtubules.

Actins↗