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T Ashida

Publications and source records attributed to T Ashida.

At least 55 records · Page 3Linked to original sources
PubMed1997

Types of organic solvents used in small- to medium-scale industries in Japan; a nationwide field survey.

OBJECTIVE: The aim of the present survey is to identify organic solvents commonly used in various workplaces in Japan. METHODS: A total of 24 occupational health service institutions (OHSI) distributed nationwide in Japan offered data on types of solvent workplaces, types of solvents used therein, and the solvent concentrations surveyed in a 2-month period between April and May 1996 to form a data base (OHSI data base, consisting of 1597 cases). Separately, Kyoto Industrial Health Association (KIHA) offered information on 948 cases studied during a 1-year period ranging from April 1995 to March 1996 (KIHA data base). The two data bases were treated in parallel to examine the reproducibility of the results. RESULTS: Detection prevalence was very low (0-1%) for almost half of the 47 legally regulated solvents. Among the solvents in use, toluene was most frequently detected, although the prevalence appeared to be reduced as compared with that recorded for the early 1980s. The most frequently observed solvent combinations comprised toluene, xylenes, and ethyl acetate in the OHSI data base and toluene, xylenes, and methanol in the KIHA data base. Contrary to the case in the 1980s, dichloromethane was used more often than trichloroethylene as a degreasing agent in the present survey. No use was detected for carbon tetrachloride, chloroform, 1,2-dichloroethane, 1,2-dichloroethylene, or 1,1,2,2-tetrachloroethane except for research purposes. CONCLUSIONS: Toluene remained the most common solvent and was used in combination with xylenes, ethyl acetate, and methanol. There was an increase in the use of dichloromethane as a degreasing agent.

Acetates↗
PubMed1997

Crystallization and preliminary X-ray analysis of a truncated family A alkaline endoglucanase isolated from Bacillus sp. KSM-635.

The catalytic domain of an alkaline endo-1,4-beta-glucanase (family A) isolated from Bacillus sp. KSM-635 (Mr = 40.2 kDa) was crystallized using the hanging drop vapor diffusion method. Two different crystal forms were obtained. Form 2 crystals (trigonal space group R3 with cell dimensions of a = b = 111.9 and c = 207.1 angstroms in a hexagonal lattice) were found to be more stable than form 1 ones upon X-ray irradiation. A full data set for form 2 crystals has been collected up to 3.3 angstroms resolution.

Amino Acid Sequence↗
PubMed1997

High-resolution crystal structure of M-protease: phylogeny aided analysis of the high-alkaline adaptation mechanism.

M-protease is a subtilisin-family serine protease produced by an alkaliphilic Bacillus sp. strain. Optimal enzymatic activity of the protein occurs at pH 12.3. The crystal structure of M-protease (space group P2(1)2(1)2(1), a = 62.3, b = 75.5, c = 47.2 A) has been refined to a crystallographic R-factor of 17.2% at 1.5 A resolution. The alkaline adaptation mechanism of the enzyme was analyzed. Molecular phylogeny construction was used to determine the amino acid substitutions that occurred during the high-alkaline adaptation process. This analysis revealed a decrease in the number of negatively charged amino acids (aspartic acid and glutamic acid) and lysine residues and an increase in arginine and neutral hydrophilic amino acids (histidine, asparagine and glutamine) residues during the course of adaptation. These substitutions increased the isoelectric point of M-protease. Some of the acquired arginine residues form hydrogen bonds or ion pairs to combine both N- and C-terminal regions of M-protease. The substituted residues are localized to a hemisphere of the globular protein molecule where positional shifts of peptide segments, relative to those of the less alkaliphilic subtilisin Carlsberg, are observed. The biased distribution and interactions caused by the substituted residues seem to be responsible for stabilization of the conformation in a high-alkaline condition.

Adaptation, Physiological↗
PubMed1997

Increase in erythrocyte volume in patients with chronic atrial fibrillation.

Non-anemic macrocytosis is occasionally observed in patients with a history of alcoholism or chronic liver disease. Recently we reported that patients with atrial fibrillation (AF) had larger erythrocytes than normal subjects. In the present study, we examined the temporal changes in hematologic measurements during the development of AF in 88 male patients (chronic AF: 49, paroxysmal AF: 39), and compared alcohol intake among the groups. The mean corpuscular volume of erythrocytes was significantly greater in chronic AF patients, both before (98.1 +/- 6.1 (SD) fl p < 0.05) and after onset (within 6 months: 98.4 +/- 7.1 fl p < 0.05; 1 year: 98.6 +/- 6.2 fl p < 0.01), compared with 300 age-matched male control subjects with sinus rhythm (95.9 +/- 3.6 fl). Hematocrit increased significantly with development of AF in both chronic and paroxysmal AF patients (p < 0.005). Mean daily alcohol consumption did not differ significantly among the control, chronic AF and paroxysmal AF groups. Our findings indicate that erythrocyte size is already larger in patients with chronic AF before the condition develops.

Adult↗
PubMed1997

A pilot study of centrifugal leukocyte apheresis for corticosteroid-resistant active ulcerative colitis.

Corticosteroids are effective in bringing about a clinical remission in patients with ulcerative colitis. However, in severely relapsed cases, corticosteroids are not always effective even when a high dosage is administered. In addition, the long-term use of corticosteroids often causes serious side effects. Therefore, an alternative treatment for active ulcerative colitis is necessary in order to avoid these clinical problems. In the present pilot study, the efficacy of leukocytapheresis using a centrifugal procedure was evaluated for corticosteroid-resistant, active ulcerative colitis. Fourteen patients with corticosteroid-resistant severely active ulcerative colitis were treated by leukocytapheresis. Thirteen patients (92.9%) achieved clinical remission within 4 weeks after the apheresis, and remained in remission for 8 months on average without any additional corticosteroid therapy. In the remaining patient, in whom remission was not induced, a total colectomy was performed immediately after the fourth course of leukocytapheresis. No significant side effects were noticed throughout the therapy. Both colonoscopic and histological examinations confirmed the beneficial effect of this procedure in terms of the reduction of severe inflammation of the affected colon. We found that the expression of two adhesion molecules, L-selectin and VLA4a, on the surface of peripheral leukocytes was decreased after this new therapy.

Adrenal Cortex Hormones↗
PubMed1997

[Trends in the prescriptions for antihypertensive drugs in elderly patients].

We compared trends in the prescription of antihypertensive drugs in elderly patients with those in middle-aged patients. We analyzed prescriptions given to 141 patients with hypertension who were 65 years old or older (mean age, 73 years) and to 511 patients with hypertension who were 64 years old or younger (mean age, 59 years). The numbers of drugs prescribed did not differ between the elderly and the non-elderly patients. In both groups, about 50% of patients were given prescriptions for one antihypertensive drug, about 40% were given prescriptions for two drugs, and about 10% were given prescriptions for three drugs. Calcium antagonists were the agents most commonly prescribed as monotherapy (51.4% and 56.4% in the non-elderly and elderly respectively; n.s.); followed by beta-blockers (32.2% and 25.6%; n.s.). Diuretics were prescribed less often to non-elderly patients than to elderly patients (5.1% and 10.0%; p < 0.01). When prescriptions for more than one antihypertensive agent were included in the analysis, calcium antagonists were still the most commonly prescribed agents (63.8% and 66.4%; n.s.), followed by the beta-blockers (53.3% and 66.4%; p < 0.05). Diuretics were less commonly prescribed to non-elderly patients (13.5% and 21.3%; p < 0.005), while ACE inhibitors (19.0% and 11.6%; p < 0.005) and beta-blockers (52.3% and 44.0; p < 0.05) were more commonly prescribed to non-elderly patients. When we classified the data according to the time of the first visit, we found that patients whose first visit was earlier were more likely to have been given a prescription for a diuretics, whether they were elderly or non-elderly. Calcium antagonists were the most commonly prescribed agents in all time periods studied, followed by beta-blockers. Comparison of our results with those of a similar study done at our clinic in 1990 showed that the use of calcium antagonist monotherapy doubled in both groups (non-elderly: 26.4% in 1990 to 51.4% in 1995, p < 0.001; elderly: 29.5% in 1990 to 56.4% in 1995, p < 0.001) and that the use of diuretics declined markedly (non-elderly; 20.3% to 5.1%, p < 0.001; elderly: 30.2% to 10.0%, p < 0.001). A similar trend was seen when prescriptions for more than one antihypertensive drug were included in the analysis.

Aged↗
PubMed1997

Effect of cilazapril and salt on Ca2+ extrusion in arterial smooth muscle of Dahl rats.

We examined effects of salt and cilazapril on the Ca pump and Na/Ca exchange system in arterial smooth muscle of Dahl salt-sensitive (DS) rats. Twenty-four DS rats were assigned to four groups. H and H+ rats were fed a high salt diet; L- and L+ rats were fed a low salt diet. H+ and L+ were administered cilazapril. Aortic rings were superfused with physiologic saline and isometric tension was measured. Relaxation of low Na+-induced contraction was promoted by the removal of external Ca. Cilazapril significantly decreased blood pressure in both the high and low salt diet groups. The inhibition of renin-angiotensin system by cilazapril showed that Ca extrusion by ATP-driven Ca pump was decreased by salt loading, and that Ca extrusion by Na/Ca exchange was increased by salt loading. There was a negative correlation between Ca extrusion by Ca pump and blood pressure, and a positive correlation between Ca extrusion by Na/Ca exchange and blood pressure. These results suggest that the decrease of Ca2+ extrusion by ATP-driven Ca pump resulting from a high salt diet might lead to an elevation in the concentration of cellular Ca2+ and contribute to the mechanism of hypertension in DS rats, and that Ca2+ extrusion by the Na/Ca exchange might be increased in compensation for an increase in cellular Ca2+ concentration on the high salt diet.

Adenosine Triphosphate↗
PubMed1997

[Experimental study on the pathogenesis of mitral annular calcification: calcium deposits in mitral complex lesions induced by vagal stimulation in rabbits].

Cervical vagal stimulation in rabbits frequently causes peculiar mitral complex lesions which are detected by deposition of colloidal carbon. The present study examined the effects of vagal stimulation on the calcium (Ca) contents in the mitral complex lesions. Anesthetized rabbits were forced into the supine position with electrocardiographic monitoring. The animals were divided into those with vagal stimulation (n = 37), and those without manipulation as controls (n = 25). Colloidal carbon (1 ml) was intravenously injected into the animals on the next day. All animals were sacrificed after 1 week. After perfusion of the heart by heparinized saline, Ca content per g myocardium in the mitral annulus, papillary muscle, free wall or apex in the left ventricle was measured by the atomic absorption method. Immediately after vagal stimulation, bigeminy due to premature ventricular contractions was observed in 76%, and systolic murmur was heard in 30%. Mitral complex lesions detected by carbon deposits were found in 73% of the rabbits with vagal stimulation. Ca content in the mitral annulus or papillary muscle was significantly greater than that in the free wall or apex (p < 0.001). Ca content in the mitral annulus was significantly greater in the rabbits with vagal stimulation than in the control group (p < 0.001). In the former group, Ca content in the mitral annulus in animals with mitral complex lesions was significantly greater than that in those without mitral complex lesions (p < 0.01). These results suggest that these mitral complex lesions might provide an experimental model of mitral annular calcification, and that the autonomic nervous system and arrhythmia might be involved in the mechanism of this calcification.

Animals↗
PubMed1997

[QRS axis shift in deep breathing].

We examined changes in mean QRS axis of electrocardiogram during the deep breathing test in outpatients with hypertension, ischemic heart disease, and/or diabetes mellitus. The mean age of all patients (n = 596; male 327, female 269) was 63.0 years (male 62.7 years, female 63.4 years). The average of the mean QRS axis in all patients was shifted to the right during deep inspiration. The changes in mean QRS axis during deep breathing test were more than 60 degrees in 27 patients (4%) (mean age: 70.0 years), 30-59 degrees in 118 patients (20%) (mean age: 65.5 years), and 0-29 degrees in 451 patients (76%) (mean age: 61.9 years). These results suggest that the changes in mean QRS axis during deep breathing are greater in the aged patients.

Aged↗
PubMed1996

Effects of growth temperature on the fatty acid composition of the free-living nematode Caenorhabditis elegans.

The effects of growth temperature on the fatty acid compositions of the phosphatidylcholine (PC), phosphatidylethanolamine (PE), and total lipid (TL) fractions of the free-living nematode Caenorhabditis elegans were investigated. A reduction in growth temperature from 25 to 15 degrees C caused the proportions of eicosapentaenoic acid (20:5n-3) to increase from 23.6 to 32.5% in the PC, from 7.4 to 10.8% in the PE, and from 12.9 to 19.9% in the TL fractions. Conversely, the levels of dihomo-gamma-linolenic acid (20:3n-6) and arachidonic acid (20:4n-6) in these phospholipid fractions and the TL fraction both decreased with decreasing growth temperature. Analysis of the positional distribution of fatty acids in the PC fraction revealed that the change in the composition of C20 polyunsaturated fatty acid was obvious in position sn-2. Lowering the growth temperature induced an increase in the level of the diacyl subclass of PE from 58% at 25 degrees C to 71% at 15 degrees C, with a concomitant decrease in the levels of the alkylacyl and alkenylacyl subclass of PE of C. elegans. These changes observed in the phospholipids of C. elegans might be one mechanism for adaptation to low temperature.

Adaptation, Physiological↗
PubMed1996

Delivery after bone marrow transplantation with total lymphoid irradiation for severe aplastic anemia.

A 28-year old woman delivered a normal child at 85 months after bone marrow transplantation (BMT) for severe aplastic anemia (SAA). BMT was done after conditioning with cyclophosphamide (CY: 50 mg/kg/day for 4 days), anti-lymphocyte globulin (ALG: 50 mg/kg/day for 3 days) and total lymphoid irradiation (TLI: 5 Gy in a single fraction). Ovarian shielding was not done during irradiation. Six months after BMT, she gained normal menstruation spontaneously. Serum gonadotrophin levels were within the normal range, with an LH level of 34.6 mIU/ml (normal: 1-36 mIU/ml) and an FSH level of 13.4 mIU/ml (normal: 1-30 mIU/ml), at 38 months after BMT. She became pregnant 8 years after BMT and delivered a female child, who is now 3 years old and shows normal development.

Adult↗
PubMed1996

Efficacy of high-frequency ultrasound probes for the preoperative staging of invasion depth in flat and depressed colorectal tumors.

BACKGROUND: Flat and depressed nonpolypoid types of colorectal tumors have drawn much attention. Since endoscopic mucosal resection technique is available, it is of great importance to distinguish intramucosal carcinoma from invasive carcinoma because determination of the invasion depth is essential for choosing this therapy. The usefulness of high-frequency (20 MHz) ultrasound probes for preoperative staging of invasion depth in this type of colorectal tumor was evaluated. METHODS: Forty-nine cases of flat and depressed tumors were examined with the ultrasound probe and diagnostic accuracy was confirmed by comparing ultrasonic images with the pathologic findings of the specimens resected either by endoscopic mucosal resection or surgical operation. RESULTS: The normal colonic wall was visualized as a nine-layered structure and the muscularis mucosae was depicted in 37 (76%) of 49 cases. Flat and depressed tumors were visualized as hypoechoic lesions and the invasion depth was accurately diagnosed in 43 (88%) of 49 lesions. CONCLUSIONS: High-frequency ultrasound probes proved to be useful in determining the invasion depth and therapeutic strategy in flat and depressed colorectal tumors.

Adenoma↗
PubMed1996

Effects of dietary salt and angiotensin-converting enzyme inhibitor on ATP-driven Ca pump and Na/Ca exchange in aortic rings of Dahl rats.

We examined effects of dietary salt and cilazapril on ATP-driven Ca pump and Na/Ca exchange system in arterial smooth muscle of Dahl salt-sensitive (DS) rats. Twenty-four DS rats were assigned to 4 groups. H- and H+ rats were fed a high-salt diet. L- and L+ rats were fed a low-salt diet. H+ and L+ were administered cilazapril. Aortic rings were superfused with physiological saline, and isometric tension was measured. Relaxation rates of low-Na(+)-induced contractions were promoted by the removal of external Ca. Cilazapril significantly decreased blood pressure in both the high- and low-salt diet groups. Salt loading reduced relaxation rates in 1.2 mmol/l Na+, and enhanced the increase in relaxation rates from 1.2 mmol/l to normal Na+. A negative correlation was observed between Ca extrusion by the Ca pump and blood pressure, and a positive correlation was observed between Ca extrusion by Na/Ca exchange and blood pressure. The results suggest that the decrease of Ca2+ extrusion by the ATP-driven Ca pump resulting from a high-salt diet might lead to an elevation in the concentration of cellular Ca2+.

Adenosine Triphosphate↗
PubMed1996

[Differentiation of hypertrophic cardiomyopathy and hypertensive cardiac hypertrophy using the patterns of interventricular septum hypertrophy].

The patterns of interventricular septal hypertrophy were analyzed on two-dimensional echocardiograms to differentiate hypertrophic cardiomyopathy (HCM) from hypertensive cardiac hypertrophy. The control group comprised 110 patients without cardiovascular disease who were matched for age and gender with the hypertension group. The hypertension group comprised 110 patients with uncomplicated essential hypertension, and the HCM group comprised 32 patients in whom the wall thickness of the interventricular septum was 12 mm or more at the mid-portion and no underlying heart disease responsible for cardiac hypertrophy was detected. The interventricular septal thickness was measured both at the thickest portion within 15 mm distal to the aortoseptal junction (basal portion: B) and at the mid-portion (M) in the end-diastolic image on the left parasternal long-axis tomograms, and the B/M ratio was calculated in each patient. The B/M ratio was 1.07 +/- 0.16 in the control group, 1.19 +/- 0.18 in the hypertension group, and 0.83 +/- 0.12 in the HCM group. Compared with the control group, the B/M ratio was significantly high in the hypertension group (p < 0.05) and significantly low in the HCM group (p < 0.01). These results indicate that hypertrophy of the interventricular septum is dominant at the basal portion in hypertensive patients but at the mid-portion in patients with HCM.

Aged↗
PubMed1996

[Experimental production of tricuspid valve and papillary muscle lesions by premature ventricular contractions due to ventricular stimulation in rabbits].

Ventricular bigeminy or trigeminy can spontaneously occur in anesthetized rabbits forced into the supine position. Premature ventricular contractions (PVCs) of this type are characterized by a long coupling time and superimposition of the following P waves. Rabbits with PVCs of this type frequently develop peculiar mitral complex lesions which are detected by deposition of colloidal carbon. This study examined the effects on the tricuspid complex of artificial PVCs induced by left ventricular pacing in rabbits. Anesthetized rabbits were forced into the supine position under electrocardiographic monitoring. The animals were divided into those with spontaneous PVCs, those with artificial PVCs, and those without PVCs as controls. Colloidal carbon (1 ml) was intravenously injected into the animals the next day. All animals were sacrificed after 1 week. Tricuspid complex lesions were found in 2.0% of animals with spontaneous PVCs, in 17.6% of those with artificial PVCs, and in none of the controls. These results indicate that artificial PVCs induced by left ventricular pacing can cause peculiar tricuspid complex lesions.

Animals↗
PubMed1995

Structure of a new alkaline serine protease (M-protease) from Bacillus sp. KSM-K16.

An alkaline serine protease, M-protease, from Bacillus sp. KSM-K16 has been crystallized. Two morphologically different crystal forms were obtained. Crystal data of form 1: space group P2(1)2(1)2(1), a = 47.3, b = 62.5, c = 75.6 A, V = 2.23 x 10(5) A(3), Z = 4 and V(m) = 2.09 A(3) Da(-1). Crystal data of form 2: space group P2(1)2(1)2(1), a = 75.82 (2), b = 57.79 (2), c = 54.19 (1) A, V = 2.29 (2) x 10(5) A(3), Z = 4 and V(m) = 2.15 A(3) Da(-1). The crystal structure of M-protease in form 2 has been solved by molecular replacement using the atomic model of subtilisin Carlsberg (SBC) which is 60% homologous with M-protease, and refined to the crystallographic R-factor of 0.189 for 7004 reflections with F(o)/sigma(F) > 3 between 7 and 2.4 A resolution. The final model of M-protease contains 1882 protein atoms, two calcium ions and 44 water molecules. The three-dimensional structure of M-protease is essentially similar to other subtilisins of known structure. The 269 C(alpha) positions of M-protease have an r.m.s. difference of 1.06 A with the corresponding positions of SBC. The crystal data of form 2 are close to those of SBC, though the structure determination of form 2 made it clear that it is not isomorphous to the crystal structure of SBC. The deletions of amino acids occur at the residues 36' and 160'-163' compared with SBC (numerals with primes show the numbering for SBC). The deletion of the four residues (160'-163') may significantly affect the lack of isomorphism between M-protease and SBC.

Journal Article↗