Search PubMed⌕ Search

Biomedical subjects

S Koda

Publications and source records attributed to S Koda.

At least 37 records · Page 2Linked to original sources
PubMed1998

A retrospective cohort study on retirement and mortality for male employees of a local government of Japan.

This retrospective cohort study describes the mortality pattern after retirement and examines associations of the last job position and work status immediately after retirement with the mortality for male employees who retired from Kochi prefectural government. The subjects include 514 retirees over the 1977-1981 period, who were followed for 9.8 years after retirement, and 721 retirees over the 1982-1986 period, who were followed for 5.8-9.8 years. All subjects were hypothesized to have retired at a normal retirement age. Mortality risk was stable through the follow-up period subdivided into two-year intervals in both cohorts of retirees. In both cohorts, men who did not work immediately after retirement had increased mortality within the first two years of retirement compared with those who worked immediately after retirement. This finding is consistent with the mortality pattern explained by health related selection into working after retirement. The present study does not show a meaningful mortality fluctuation over the post-retirement period among male employees of the local government. Lack of information on ages and health status at retirement of individual subjects hampers discussion about causality of observed associations between two study variables concerning pre- and post-retirement characteristics and post-retirement mortality.

Aged↗
PubMed1998

Clinical characteristics differentiating bacteriologically positive pulmonary tuberculosis patients from negative ones in Mongolia.

The objective of this study is to clarify clinical characteristics which differentiate bacteriologically positive pulmonary tuberculosis patients from negative ones in Mongolia. The subjects include 338 patients aged 16 years and older who had undergone bacteriological examinations. Of them, 107 patients (31.7%) were confirmed bacteriologically. The proportion of bacteriological positive results increased significantly among patients who had cavities in the roentgenographic examination, cough at diagnosis and the family history of tuberculosis. Addressing these clinical characteristics will contribute to raising not only the sensitivity of the sputum examination, but also the specificity of the roentgenographic examination in the diagnostic process of tuberculosis.

Adult↗
PubMed1997

A follow-up study of preventive effects on low back pain at worksites by providing a participatory occupational safety and health program.

Low back pain is still a common and serious issue at worksites. In order to evaluate preventive effects on low back pain by providing a participatory occupational safety and health program, we conducted a 10 year follow-up study at the Tokyo Metropolitan Bureau of Waste Management and examined yearly changes in the number of compensated and claimed low back pain. The participatory occupational safety and health program is based on a small-sized group and joint employee-employer involvements. This program includes analysis of occupational accidents, revision of the safety procedure manual, participatory training classes, improving and evaluating working procedures and personal protective equipment , and so on. The number of compensated low back pain from 1984 to 1994 has decreased from 318 to 87, and the number of claimed low back pain has decreased from 343 to 92. These results suggest that the participatory occupational safety and health program is effective in prevention of low back pain.

Follow-Up Studies↗
PubMed1997

[A study of waste anesthetic gases monitoring and working environmental controls in hospital operating rooms].

There are hazardous factors threatening health care workers, and many hazardous chemical substances have been reported in operating rooms, central supply facilities, laboratories and so on. In Japan, little attention has been paid to exposure to these chemicals and to working environmental controls. Waste anesthetic gases are chemicals concerned, and we conducted environmental monitoring continuously and measured exposure to nitrous oxide, isoflurane and sevoflurane in operating rooms, and examined working environmental controls. The average environmental concentrations of nitrous oxide were about 400 ppm in anesthetists' working areas, and about 180 ppm in surgeons' and instrument nurses' working areas under unscavenged conditions. Under scavenged conditions, environmental concentrations were 70-190 ppm in anesthetists' zones, and 70-90 ppm in surgeons' and instrument nurses' zones. Even under scavenged conditions, operating room personnel are presumed to be exposed to high concentrations of nitrous oxide above ACGIH's TLV and NIOSH's REL. The level of exposure of isoflurane and sevoflurane was 2-4 ppm. Managing general ventilation system and airflow direction, working area under scavenged system, environmental concentration levels of nitrous oxide could be reduced to 20-30 ppm. In order to control occupational exposure to anesthetic gases, it is not sufficient to merely adapt scavenging systems in operating rooms. Working environmental control and occupational hygiene management should be required.

Air Pollutants, Occupational↗
PubMed1996

Nitric oxide (NO)-releasing pathway of FK409 in the presence of sulfhydryl-bearing compounds.

PURPOSE: We have recently reported that degradation of FK409 with generation of NO is spontaneous and is accelerated in the presence of sulfhydryl-bearing compounds, such as L-cysteine (Cys) and glutathione (GSH). The purpose of the present study is to investigate the NO-releasing pathway of FK409 in the presence of sulfhydryl-bearing compounds. METHODS: The degradation process of FK409 in the presence of Cys or GSH was investigated by means of 1H-nuclear magnetic resonance (NMR) spectroscopy and high-performance liquid chromatography (HPLC). RESULTS: The degradation of FK409 in the presence of Cys was dependent on concentration of Cys, and showed pH-dependency, accelerating with an increase in pH. The 1H-NMR spectra of FK409 with Cys suggested that time-dependent elimination of the hydrogen atom at the alpha-position of the nitro moiety (5-position) was accelerated by Cys in weakly alkaline solution. Cys and GSH were transformed readily, concomitant with FK409 degradation, to give their oxidized forms and probably S-nitrosothiols. CONCLUSION: The effect of sulfhydryl-bearing compounds on FK409 degradation is due to the acceleration of deprotonation of the hydrogen atom at the 5-position by thiolate anion as well as hydroxyl ion. Sulfhydryl-bearing compounds reacted with the released NO resulting in formation of disulfides via intermediate S-nitrosothiols.

Chromatography, High Pressure Liquid↗
PubMed1996

[Characteristics of pulmonary tuberculosis patients by mode of detection--comparison of patients detected between 1993-94 with those detected between 1986-88].

In a previous study it was concluded that pulmonary tuberculosis (TB) patients who were detected at a hospital, excluding those detected by mass screening (group A), should be classified into three distinct groups. Namely some patients were detected only after the onset of TB symptoms (group B), with the others being treated for other diseases before being diagnosed as having TB (group C). In group C, some patients were detected because of manifesting additional symptoms related to TB such as cough (group C-1), while the remaining patients were detected by chance while being examined for other diseases (group C-2). Four groups respectively had specific characteristics which differentiated each other. The aim of this study is to elucidate changes of proportion and characteristics of group C compared to the former results. Pulmonary TB patients, who were registered between 1993 and 1994, in the area served by Kochi Prefectural Chuo Health Center (N = 332) were compared with those registered between 1986 and 1988 in the area. The results were as follows. 1) The proportion of group C was significantly higher in the period of 1993-94 than during 1986-88. The proportion of elderly people in group C was higher in the period of 1993-1994 than in 1986-88. The proportion of group C is projected to continue increasing as the proportion of elderly among the population increases. 2) The proportion of smear positive cases by sputum was lower in group C-2 than in group B and group C-1. The proportion of either inactive TB or non TB cases was estimated to be higher in group C-2 than in group B and group C-1. 3) In group C-1, the proportion of bacillus positive cases was higher in the period of 1993-94 than 1986-88. The elongation of the interval between the onset of symptoms and diagnosis (total delay) was related to the severity of bacillus finding.

Adolescent↗
PubMed1996

[Supporting roles of health centers in community health practice by municipalities].

Staff of community health centers are expected to support those of municipalities so that they can identify health relevant issues in their communities, plan strategies to resolve the issues, implement them and evaluate the action. To illustrate the role of community health centers, the authors report the process of health promotion practice in Taisho-cho, Kochi prefecture, which was supported by Kubokawa health center. The health center took the initiative in identifying issues in community health through analyzing available information. In a practice setting, the health center facilitated involvement and participation by the residents and cooperated with other community resources. The process of support is discussed from the point of view of community organization practice.

Ambulatory Care Facilities↗
PubMed1995

Acceleration of nitric oxide (NO) release from FK409, a spontaneous NO releaser, in the presence of sulfhydryl-bearing compounds.

PURPOSE: Recently, we have reported that FK409 spontaneously releases nitric oxide (NO) in solution. In the present study, the influence of L-cysteine (Cys) and glutathione (GSH), which are typical sulfhydryl group-bearing compounds, on NO release from FK409 and biological action of FK409 was examined. METHODS: We evaluated the effects of Cys and GSH on NO release from FK409 by nitrite analysis or detection with a chemiiluminesence analyzer. In a biological study, the influence of Cys on inhibition of rat platelet aggregation of FK409 was investigated. In addition, the above mentioned characteristics of FK409 were compared with those of isosorbide dinitrate (ISDN). RESULTS: FK409 decomposed spontaneously with generation of nitrite in solution. Both Cys and GSH accelerated decomposition of FK409 and nitrite generation from FK409 in a concentration-dependent manner. When the NO levels in the headspace of FK409 solutions (0.5 mM) reached equilibrium with and without 25 mM Cys, the constant rate for NO release from FK409 in the presence of Cys was 13 times larger than that in the absence of Cys. In biological study, FK409 (100 microM) showed 56 and 90% inhibition of rat platelet aggregation in the absence and presence of 10 mM Cys, respectively, whereas ISDN (100 microM) showed 10 and 23% inhibition, respectively. CONCLUSIONS: Decomposition of FK409 with generation of NO is spontaneous, and is accelerated in the presence of sulfhydryl group-bearing compounds, thereby potentiating the biological action of FK409.

Animals↗
PubMed1995

A new nitric oxide (NO) releaser: spontaneous NO release from FK409.

The remarkable vasorelaxant and anti-platelet effects of FK409 have been reported to be due to nitric oxide (NO) release. The purpose of the present study is to investigate the spontaneous NO-releasing pathway of FK409 in aqueous solutions. 1H-NMR spectra of FK409 suggested that the compound underwent a time-dependent elimination of the hydrogen atom at alpha-position of the nitro moiety (at the 5-position) in weakly alkaline solutions. In addition, the degradation of FK409 monitored by HPLC showed a pH-dependency accelerating with an increase of pH. These results revealed that the first step in the degradation of FK409 might be the hydroxyl ion-dependent subtraction of the hydrogen atom at the 5-position. On the other hand, NO release from FK409 also exhibited a pH-dependency, and the velocity of NO liberation was markedly enhanced above pH 6. Furthermore, a linear relationship between the rate of FK409 degradation and that of NO formation was observed, indicating that the rate-limiting step for NO formation is the same as that for degradation. Thus, the rate-limiting process of NO formation from FK409 is due to the deprotonation reaction of the hydrogen atom at the 5-position by hydroxyl ions. The deprotonation process appears to be an essential step for both FK409 degradation and NO release. On the basis of the results, a possible kinetic scheme for NO release from FK409 is proposed.

Buffers↗
PubMed1995

Improving workplace environments and working conditions at worksites providing school lunch service in Japan.

With the cooperation of All Japan Prefectural and Municipal Workers' Union, we have started an overall program on occupational safety and health from 1984. This program has several strategies aimed at preventing occupational injuries and work-related diseases. At first, we analyzed the relationship between work-related hazards and occupational factors, and to identify dangerous or hazardous factors in the workplace. Second, we have conducted a couple of intervention studies at worksites and evaluated these improvements. Third, we discussed the priority, feasibility and cost of improvements with Workers' Union members and school lunch workers. Fourth, during the last decade, Workers' Union and many researchers have demanded that regulations be implemented which would establish comprehensive safety and health programs. Fifth, we provided the workers with procedures on how to improve working environments and conditions. These education and training programs are provided for small-group working ("safety and health circle"), and demonstrate to workers their abilities to solve occupational safety and health problems and to empower them with respect to health-related issues. Finally, we discussed and evaluated the preventive effects of improving workplace environments and working conditions. The overall program on occupational safety and health at worksites is developing nationwide and is gradually taking effect.

Cooking↗
PubMed1994

Mechanism of optical isomerization of (S)-N-[1-(2-fluorophenyl)-3,4,6,7- tetrahydro-4-oxopyrrolo[3,2,1-jk] [1,4]-benzodiazepine-3-yl]-1H- indole-2-carboxamide (FK480) in soft capsules containing polyethylene glycol 400 and glycerol.

FK480 is a new synthetic non-peptide antagonist of cholecystokinin (CCK)-A receptors. The dosage form of FK480 is a soft capsule containing a solution of FK480 in a mixture of polyethylene glycol 400 (PEG 400) and glycerol to improve its bioavailability. Studies on the stability of this FK480 dosage form revealed that the main degradation occurred by optical isomerization at the asymmetric C-3 position of the pyrrolobenzodiazepine ring. The degradation reaction was accelerated by formic acid formed in a mixture of PEG 400 and glycerol. Addition of amino acids to the capsule solution retarded the isomerization by reacting with formic acid. Therefore, formic acid appears to accelerate optical isomerization of FK480.

Benzodiazepinones↗
PubMed1994

The effects of frequently rotating shiftwork on sleep and the family life of hospital nurses.

The effects of three frequently rotating shifts in an irregular sequence on the daily activities of 239 Japanese female hospital nurses were studied by the time-budget method. The nurses recorded their daily activities for several consecutive days. The questionnaire was returned by 80.8% of the participants, and recordings of 1016 days were analysed. A two-way analysis of variance clarified that the shift combination influenced the daily activities. The most distinct result was that nurses spent significantly more time on free-time activities on the day when they worked the night shift followed by the evening shift than they did on the day when they worked any other shift combination. Nurses offset sleep deprivation either by sleeping during the day before and after working the night shift (82-100%) or by sleeping 2 to 4 h later in the morning after working the evening shift and on days off. There was a strong positive correlation between total sleep time (including day sleep) and the length of the interval between two consecutive shifts (r = 0.95, p < 0.001). This result suggests that more than 16 h between work shifts is required to allow more than 7 h of total sleep time. In an analysis by household status, nurses who had young children (average age, 2.8 years) slept less and spent less time on free-time activities than did other nurses.

Activities of Daily Living↗
PubMed1993

Tautomeric phenomenon of a novel potent immunosuppressant (FK506) in solution. I. Isolation and structure determination of tautomeric compounds.

Tautomeric phenomenon was observed in the HPLC chromatogram obtained from a novel potent immunosuppressant, FK506, in ethanol solution. Two tautomeric compounds derived from FK506 were isolated and purified by HPLC. Their structures were elucidated by spectral analyses. The mechanisms for this tautomerization were also established based on the results of structure analysis.

Isomerism↗
PubMed1992

Determination of cefixime and its metabolites by high-performance capillary electrophoresis.

Cefixime (CX), an oral cephalosporin antibiotic, and its metabolites in human digestive organs were separated by various modes of high-performance capillary electrophoresis. The zone electrophoresis mode in phosphate buffer (pH 6.8) containing 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulphonate gave the best separation, permitting the complete resolution of CX and all of five metabolites. On the other hand, the plain zone electrophoresis mode in phosphate buffer (pH 6.8) offered a simple procedure for the direct determination of urinary CX concentration using intact urine samples.

Anti-Infective Agents, Urinary↗
PubMed1991

X-ray structural studies and physicochemical characterization of (E)-6-(3,4-dimethoxyphenyl)-1-ethyl-4-mesitylimino-3-methyl- 3,4-dihydro-2(1H)-pyrimidinone polymorphs.

The polymorphism of (E)-6-(3,4-dimethoxyphenyl)-1-ethyl-4-mesitylimino-3-methyl-3,4-di hydro- 2(1 H)-pyrimidinone (FK664; 1) was characterized by using X-ray powder diffractometry, differential scanning calorimetry (DSC), and IR spectroscopy. Structures of two polymorphs (Forms A and B) were determined by X-ray crystallographic analysis. Form A crystallized in the monoclinic space group P2(1)/c, with a = 13.504(2), b = 6.733(1), c = 24.910(8) A, beta = 96.55(4) degrees, z = 4, and dcal = 1.203 g/cm3, while Form B crystallized in the same space group, with a = 8.067(2), b = 15.128(4), c = 18.657(4) A, beta = 102.34(3) degrees, z = 4, and dcal = 1.216 g/cm3. The conformational features of 1 were very similar between the two polymorphs. Compound 1, in both crystal forms, took an energetically reasonable conformation in three rigid planes, such as 2-pyrimidone, trimethylphenyl, and dimethoxyphenyl rings, but the molecules were packed in different ways between the two polymorphs. In the Form B crystal, a short contact was possible, to form pi-pi interactions between two dimethoxyphenyl groups related with the inversion center in the crystal lattice; this interaction seems to contribute to stabilizing the crystal structure of Form B. Both Forms A and B showed only one endothermic peak due to fusion at 115 and 140 degrees C, respectively, on the DSC thermograms; therefore, it is suggested that there are no transition points between the two polymorphs. The heats of fusion obtained from the DSC thermograms were 33.2(2) kJ/mol for Form A and 36.8(1) kJ/mol for Form B.(ABSTRACT TRUNCATED AT 250 WORDS)

Chemical Phenomena↗
PubMed1991

[An epidemiological study on low back pain and occupational risk factors among clinical nurses].

Recently medical services and nursing system are being reformed due to high medical costs and shortage of clinical nurses. The shortage of clinical nurses influences not only their working conditions but also their own health problems. In European countries and the United States, low back pain (LBP) has been reported to be one of the most common and costly health problems among clinical nurses. To estimate the occupational risk factors of LBP among nurses, a questionnaire survey of LBP and occupational risk factors was carried out in 1987 on 947 clinical nurses and as well as on 300 female clerical workers of three local governments. First, to examine the prevalence and the magnitude of the problem, we analyzed several kinds of prevalence rates of LBP and its characteristics among nurses and clerical workers. Second, a case-control study was conducted to investigate the relationship between LBP and occupational risk factors. In analyzing occupational risk factors of LBP, odds ratios, age adjusted odds ratios and 95% confidence intervals were computed. Finally, to estimate simultaneously the effect of multiple risk factors of LBP and to confirm univariate age adjusted odds ratio analyses, several multivariate analyses were performed. Point, period (a month), and lifetime prevalence rates of LBP and prevalence rate of severe LBP among clinical nurses were significantly higher than those of clerical workers (p less than 0.05-0.001, respectively). Demographic and occupational items, such as being an assistant nurse (as opposed to a registered nurse), and working in certain departments (internal medicine, orthopedic surgery, neurosurgery, psychiatry, tuberculosis ward) showed significantly higher odds ratios for LBP (p less than 0.05-0.001, for all). Many items pertaining to working conditions connected with shift work, hospitalized conditions of patients, taking breaks and holidays, working postures, weight of patients and equipment lifting and moving, working environments and so on had significantly elevated age adjusted odds ratios (p less than 0.05-0.001, for all). Intensity of work loads estimated subjectively such as 'caring for patients who are in bed', 'supporting patients when transporting and bathing them', 'preparing drugs and injections, and treating', 'observing and monitoring patients' conditions', 'instructing and explaining procedure to patients and their family' and so on also had significantly elevated age adjusted odds ratios (p less than 0.05-0.001, for all). Moreover, many items on the problems connected with working life and interpersonal relationships showed significantly higher age adjusted odds ratios (p less than 0.05-0.001). In multivariate analyses, independent variables which made a significant contribution to the model were similar to the items which had significantly elevated age adjusted odds ratios.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗