Biomedical subjects

C K Ho

Publications and source records attributed to C K Ho.

At least 73 records · Page 4Linked to original sources

PubMed1998

Genetic, physical, and functional interactions between the triphosphatase and guanylyltransferase components of the yeast mRNA capping apparatus.

We have characterized an essential Saccharomyces cerevisiae gene, CES5, that when present in high copy, suppresses the temperature-sensitive growth defect caused by the ceg1-25 mutation of the yeast mRNA guanylyltransferase (capping enzyme). CES5 is identical to CET1, which encodes the RNA triphosphatase component of the yeast capping apparatus. Purified recombinant Cet1 catalyzes hydrolysis of the gamma phosphate of triphosphate-terminated RNA at a rate of 1 s-1. Cet1 is a monomer in solution; it binds with recombinant Ceg1 in vitro to form a Cet1-Ceg1 heterodimer. The interaction of Cet1 with Ceg1 elicits >10-fold stimulation of the guanylyltransferase activity of Ceg1. This stimulation is the result of increased affinity for the GTP substrate. A truncated protein, Cet1(201-549), has RNA triphosphatase activity, heterodimerizes with and stimulates Ceg1 in vitro, and suffices when expressed in single copy for cell growth in vivo. The more extensively truncated derivative Cet1(246-549) also has RNA triphosphatase activity but fails to stimulate Ceg1 in vitro and is lethal when expressed in single copy in vivo. These data suggest that the Cet1-Ceg1 interaction is essential but do not resolve whether the triphosphatase activity is also necessary. The mammalian capping enzyme Mce1 (a bifunctional triphosphatase-guanylyltransferase) substitutes for Cet1 in vivo. A mutation of the triphosphatase active-site cysteine of Mce1 is lethal. Hence, an RNA triphosphatase activity is essential for eukaryotic cell growth. This work highlights the potential for regulating mRNA cap formation through protein-protein interactions.

Acid Anhydride Hydrolases↗

PubMed1998

Urinary 1-hydroxypyrene concentrations in coke oven workers.

OBJECTIVES: To investigate the relation of individual occupational exposure to total particulates benzene soluble fraction (BSF) of ambient air with urinary 1-hydroxypyrene (1-OHP) concentrations among coke oven workers in Taiwan. METHODS: 80 coke oven workers and 50 referents were monitored individually for the BSF of breathing zone air over three consecutive days. Exposures were categorised as high, medium, or low among coke oven workers based on exposure situations. The high exposure group (n = 18) worked over the oven. The medium and low exposure groups (n = 41 and n = 21) worked at the side of the oven for > 4 hours and < 4 hours a day, respectively. Urine was collected before the shift on the morning of day 1 and after the shift on the afternoon of day 3 to find the change of 1-OHP concentrations across the shift. RESULTS: The median (range) changes of urinary 1-OHP concentrations across the shift for various exposure situations (microgram/g creatinine) were as follows: high 182 (7 to 3168); medium 9 (-8 to 511); low 7 (-6 to 28); and referents 0.2 (-2 to 72). This change of urinary 1-OHP was highly associated with individual occupational exposure to the BSF in air (r = 0.74 and 0.64, p < 0.001). The regression model showed significant effects of individual exposures to the BSF and alcohol consumption on urinary postshift 1-OHP after adjusting for preshift 1-OHP in the total population (n = 130). More exposure to the BSF led to higher postshift 1-OHP (p < 0.001); current drinkers of > 120 g/week had lower urinary postshift 1-OHP than never and former drinkers (p = 0.01). A 10-fold increase in the average BSF in air resulted in about a 2.5-fold increase in postshift 1-OHP among the 80 coke oven workers. CONCLUSION: Urinary 1-OHP concentrations can be used as a good biomarker to assess individual exposure to the BSF in air. Alcohol drinking may modify the toxicokinetic pathway of the BSF; the effects of alcohol should be investigated further in occupational studies.

Adult↗

PubMed1998

Tamoxifen-mediated anti-cellular effect against a choriocarcinoma cell line.

The present study was undertaken to evaluate the efficacy of using steroid hormone antagonists tamoxifen and Ru486 for chemotherapy or chemoprevention of choriocarcinoma or other less malignant gestational trophoblastic diseases (GTDs) such as invasive mole. Using 4 trophoblast cell lines, we have shown that tamoxifen (>/= 2 microM) has anti-growth activity on the choriocarcinoma cell line BeWo but not on the other cell lines in a time and dose dependent manner while Ru486 invariably had no detectable effect. Based on a radioimmunoassay, we have been able to detect low levels of estrogen receptors on BeWo (6 +/- 0.4 fm/mg; Kd=438+/- 73 pM) and JEG-3 (6.55 +/- 1.2 fm/mg; Kd=710 +/- 42 pM) cells and progesterone receptors on HT (48.62 fm/mg; Kd=1,690 +/- 182 pM) and TL (8.46 fm/mg; Kd=1,540 +/- 115 pM) cells. However, there is no definite correlation between steroid responsiveness and the presence of the receptors. The mechanism of our observed tamoxifen-mediated anti-cellular effect is uncertain and characteristics commonly associated with apoptotic cell death were not observed. The level of neither wild-type nor mutant forms of the p53 protein correlated with sensitivity to tamoxifen. Our results suggest that estrogen may be a growth hormone for some trophoblasts and tamoxifen may be potentially useful for the treatment of selected cases of choriocarcinoma or other trophoblastic diseases.

Cell Line↗

PubMed1998

Temporal changes in urinary 1-hydroxypyrene concentrations in coke-oven workers.

Coke-oven workers are exposed to high concentrations of coke-oven emissions, which are comprised mainly of polycyclic aromatic hydrocarbons. We conducted a pilot study to determine the time changes in urinary 1-hydroxypyrene (1-OHP) concentrations, as a metabolite of pyrene, in coke-oven workers after exposure to a benzene-soluble fraction (BSF) of total particulates. Thirteen subjects, including 2 men (referents) from an administrative area, 6 workers who work at the sideoven, and 5 who work on the top of the oven in one coke-oven plant were studied. After 1.5 to 2 days off, subjects were monitored individually for breathing zone air BSF over 3 consecutive days in August 1995. Seven spot urine samples, including preshift and postshift urine over 3 days and preshift urine on a fourth-day morning, were collected to determine 1-OHP concentrations by fluorescent spectrophotometry. The mean ambient BSF concentrations in the sideoven and topside oven workers ranged from 18 to 159 microg/m3 and from 251 to 1362 microg/ m3, respectively, whereas the BSF concentrations in the referents were low but detectable (11 and 29 microg/m3). Urinary 1-OHP concentrations increased during the work period, from 10+/-3 and 41+/-9 microg/g creatinine (mean+/-SE) on the preshift first day to 57+/-26 and 334+/-63 microg/g creatinine on the postshift third day in the sideoven and topside oven workers, respectively. However, the urinary 1-OHP concentrations were relatively flat in the two referents. The across-shift change in urinary 1-OHP defined as postshift 1-OHP on the third day minus preshift 1-OHP on the first day was highly associated with individual mean occupational exposure to air BSF (r = 0.80, P = 0.001). Repeated-measures regression analyses revealed that daily postshift 1-OHP concentrations were marginally associated with daily air BSF. A 10-fold increase of daily air BSF resulted in a 1.67-fold increase of daily postshift 1-OHP levels (95% confidence interval = 0.99-2.83; P = 0.07). After adjusting for daily preshift 1-OHP concentrations, we found that a 10-fold increase of daily air BSF resulted in a 1.90-fold increase of daily postshift 1-OHP levels (95% confidence interval = 1.10-3.28; P = 0.03). Although the sample size is small in this study, these results indicate that daily postshift 1-OHP levels in urine are determined mainly by current occupational exposure to coke-oven emissions.

Air Pollutants, Occupational↗

PubMed1998

[The study of healthy life-style risk factors and health status for cardiovascular diseases for employees in Kaohsiung area].

To understand the healthy life style, health status and risk factors of employees, institutional employees in Kaohsiung area were studied by using questionnaire investigation and blood specimen examination. One-thousand-four hundred-fifty subjects were used, but 1147 questionnaires were completed. The complete rate was 79.1%. The reliability and validity of the healthy life style scale achieved an acceptable level. The results are as follows: 1. The mean total score of healthy life-style scale was 63.9. Four healthy behavior scored lowest: "consulted health professional about health information", "monitored self of blood pressure and blood sugar", did moderate exercise at least three times per week", "took leisure activities". 2. The severity of risk factor was as follows: (1) 32.2% of employees had abnormal value for blood cholesterol (> or = 200 mg/dl); (2) 22.9% of employees had abnormal blood pressure value; (3) 22.6% of employees were overweight or obese; (4) 16.7% of employees often smoked; (5) 13.6% of employees had abnormal values for blood triglyceride. (6) 2.1% of employees had abnormal blood sugar values. 3. 10.8% of subjects were perceieved to have a worsing health status; 14.5% of the subjects had chronic disease with physicians diagnosis and most of their (71%) were hypertersion. 4. The findings of demographic data showed that people who were male, aged over forty, had education below junior high school and those of blue collar class should be screened and monitored, for the risk factors at regular intervals. Similarly, People who are male, age below forty and blue-collar class should be encouraged to develop the healthy life-styles.

Adult↗

PubMed1998

Cytochrome P450 1A1 MspI polymorphism and urinary 1-hydroxypyrene concentrations in coke-oven workers.

Coke-oven workers are regularly exposed to a high concentration of the benzene-soluble fraction (BSF) of total particulates, which are comprised mainly of polycyclic aromatic hydrocarbons (PAHs). A metabolite of pyrene, 1-hydroxpyrene (1-OHP), is readily measured in the urine of exposed individuals. Epidemiological studies have shown that P4501A1 (CYP1A1) genotypes are associated with PAH-related lung cancer risk. The purpose of this study was to investigate whether CYP1A1 MspI genotypes modulate the relationship of individual occupational exposure to air BSF to urinary 1-OHP concentrations among coke-oven workers. We monitored individual breathing zone air BSF over 3 consecutive days in 80 coke-oven workers in Taiwan from August 1995 to February 1996. Exposure was also dichotomized by work area (topside oven workers and sideoven workers). Preshift urine on the morning of day 1 and postshift urine on the afternoon of day 3 were measured by fluorescent spectrophotometry, and blood samples were analyzed to determine the relative distributions of CYP1A1 MspI polymorphisms. The frequency of the MspI homozygous variant genotypes of CYP1A1 was 15%. Multiple linear regression showed significant effects of individual occupational exposure to air BSF and preshift 1-OHP on postshift urinary 1-OHP concentrations (P = 0.002 and P < 0.001, respectively). After adjusting for preshift 1-OHP concentrations and air BSF, subjects with the homozygous variant genotype have a 2-fold higher postshift 1-OHP levels than the combined wild-type and heterozygous (P = 0.04). In addition, a positive trend was found in postshift 1-OHP and across-shift change of 1-OHP (postshift 1-OHP - preshift 1-OHP) in decreasing order, as follows: topside oven workers with the homozygous variant trait, topside oven workers with the heterozygous variant trait, sideoven workers with the homozygous variant trait, and sideoven workers with the heterozygous trait (P < 0.001). We conclude that CYP1A1 MspI variant genotype can modify the metabolism of PAHs in coke-oven workers.

Adult↗

PubMed1998

Dimethylformamide-induced occupational liver injury--a case report.

Dimethylformamide(DMF), a widely used industrial solvent, has been reported to induce subtle to clinically overt hepatotoxicity. Liver injury due to occupational exposure through inhalation and skin contact have been sporadically reported. We reported a 42-year-old male Taiwanese who developed progressive, intermittent abdominal pain for 6 months after working in a synthetic leather factory. Acute hepatitis episode occurred after working in an enclosed and poorly-ventilated workplace for one day. Based on occupational history, pathological examination and serial liver function examinations, the case was compatible with DMF-induced acute chemical hepatitis.

Adult↗

PubMed1997

Change of cardiac beta-adrenoceptors in lead-exposed rats.

The effect of lead on cardiac beta-adrenoceptors was studied. Wistar rats used in these trials were divided into seven groups of ten animals each (A-G). Of these, groups B was given drinking water containing 0.01% lead acetate, group C 0.05%, group D 0.1%, group E 0.5%, group F 1% and group G 2% for a period of 60 days. Group A was given pure water. A radioligand-binding assay fulfilling strict criteria of receptor affinity and density was used to quantify cardiac beta-adrenoceptors. Application of a trend test indicated that both blood and heart lead levels increased significantly from group A to group G (A < G), but that beta-adrenoceptor density decreased (G < A), whereas Kd did not vary among the seven groups. Linear regression analysis showed that decrease of cardiac beta-adrenergic receptor density was closely related to elevation of blood and heart lead levels. The results show that lead exposure results in a reduction of cardiac beta-adrenoceptor density.

Animals↗

PubMed1997

Phylogeny of mRNA capping enzymes.

The m7GpppN cap structure of eukaryotic mRNA is formed cotranscriptionally by the sequential action of three enzymes: RNA triphosphatase, RNA guanylyltransferase, and RNA (guanine-7)-methyltransferase. A multifunctional polypeptide containing all three active sites is encoded by vaccinia virus. In contrast, fungi and Chlorella virus encode monofunctional guanylyltransferase polypeptides that lack triphosphatase and methyltransferase activities. Transguanylylation is a two-stage reaction involving a covalent enzyme-GMP intermediate. The active site is composed of six protein motifs that are conserved in order and spacing among yeast and DNA virus capping enzymes. We performed a structure-function analysis of the six motifs by targeted mutagenesis of Ceg1, the Saccharomyces cerevisiae guanylyltransferase. Essential acidic, basic, and aromatic functional groups were identified. The structural basis for covalent catalysis was illuminated by comparing the mutational results with the crystal structure of the Chlorella virus capping enzyme. The results also allowed us to identify the capping enzyme of Caenorhabditis elegans. The 573-amino acid nematode protein consists of a C-terminal guanylyltransferase domain, which is homologous to Ceg1 and is strictly conserved with respect to all 16 amino acids that are essential for Ceg1 function, and an N-terminal phosphatase domain that bears no resemblance to the vaccinia triphosphatase domain but, instead, has strong similarity to the superfamily of protein phosphatases that act via a covalent phosphocysteine intermediate.

Amino Acid Sequence↗

PubMed1997

Crystallization of the RNA guanylyltransferase of Chlorella virus PBCV-1.

RNA guanylyltransferase, or capping enzyme (E.C. 2.7.7.50) catalyzes the transfer of GMP from GTP to diphosphate-terminated RNA to form the cap structure GpppN. Chlorella virus capping enzyme expressed in E. coli has been purified, treated with GTP and crystallized. X-ray diffraction data have been collected from these crystals as well as for a mercury derivative obtained by soaking the crystals in thimerosal. Selenomethionine RNA guanylyltransferase was purified and crystallized in a similar fashion. The space group is C2221 and the cell parameters are a = 93.3, b = 214.9, c = 105.8 A. Two Hg atoms and two subsets of Se atoms have been localized using difference Patterson and Fourier methods, suggesting that there are two molecules per asymmetric unit.

Journal Article↗

PubMed1997

The yeast tRNA splicing endonuclease: a tetrameric enzyme with two active site subunits homologous to the archaeal tRNA endonucleases.

The splicing of tRNA precursors is essential for the production of mature tRNA in organisms from all major phyla. In yeast, the tRNA splicing endonuclease is responsible for identification and cleavage of the splice sites in pre-tRNA. We have cloned the genes encoding all four protein subunits of endonuclease. Each gene is essential. Two subunits, Sen2p and Sen34p, contain a homologous domain of approximately 130 amino acids. This domain is found in the gene encoding the archaeal tRNA splicing endonuclease of H. volcanii and in other Archaea. Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively. The presence of endonuclease in Eucarya and Archaea suggests an ancient origin for the tRNA splicing reaction.

Animals↗

PubMed1997

The anti-tumor effect of Ganoderma lucidum is mediated by cytokines released from activated macrophages and T lymphocytes.

The present study was to ascertain the immunomodulating and anti-tumor effects of Ganoderma (G.) lucidum. Polysaccharides (PS) from fresh fruiting bodies of G. lucidum (PS-G) were isolated and used to potentiate cytokine production by human monocytes-macrophages and T lymphocytes. Our results had shown that the levels of interleukin (IL)-1 beta, tumor necrosis factor (TNF)- alpha, and IL-6 in macrophage cultures treated with PS-G (100 micrograms/ml) were 5.1-, 9.8- and 29-fold higher, respectively, than those of untreated controls. In addition, the release of interferon (IFN)- gamma from T lymphocytes was also greatly promoted in the presence of PS-G (25-100 micrograms/ml). Furthermore, these cytokine-containing mononuclear cell-conditioned media (PSG-MNC-CM) were found to suppress the proliferation and clonogenicity of both the HL-60 and the U937 leukemic cell lines. DNA labeling and gel electrophoresis showed that treatment with PSG-MNC-CM markedly induced leukemic-cell apoptosis. Flow-cytometric analysis revealed that few (2.3 +/- 0.8%) apoptotic cells were seen in the control cultures, while PSG-MNC-CM treatment resulted in a significant increase in the apoptotic population both in the HL-60 (38.3 +/- 4.5%) and in the U937 (44.5 +/- 3.8%) cells. In addition, 40 to 45% of the treated leukemic cells were triggered to differentiate into mature monocytic cells expressing CD14 and CD68 surface antigens. However, PS-G alone had no such effects even at a higher dose of 400 micrograms/ml. Since untreated macrophages and T lymphocytes produced little or no cytokine, and normal MNC-CM did not suppress leukemic cell growth, it was suggestive that the anti-tumor activity of PSG-MNC-CM was derived from the elevated levels of cytokines. Antibody-neutralization studies further revealed that the anti-tumor cytokines in the PSG-MNC-CM were mainly of TNF- alpha and IFN- gamma, and these 2 cytokines acted synergistically on the inhibition of leukemic-cell growth.

Adjuvants, Immunologic↗

PubMed1997

Serum liver function profiles in coking workers.

Coking workers are regularly exposed to coke oven emissions (COE), which consist mainly of polycyclic aromatic hydrocarbons and volatile organic compounds. In a previous cross-sectional study, we found that coking and by-product workers with heavy exposure to COE in the older of two coke operation areas in Taiwan had higher serum activities of hepatic aminotransferase than the controls. In this study, we further examine the relationship of exposure to COE with liver function profiles in coking workers. Liver function profiles included serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), and total bilirubin (BIL). The exposed group included 88 workers working 3 months or more in the older coke oven plant. Fifty-nine referents, not visiting the coke operation areas in the last 3 months, came from the administrative area in the same company. Each participant wore a personal monitor that was used to measure benzene soluble fraction (BSF) of total particulates, as a surrogate of COE, for 3 consecutive days between August 1995 and February 1996. Serum liver function profiles, hepatitis B surface antigens, and anti-hepatitis C antibodies were examined in the morning following the exposure measurements. Exposure levels were categorized by exposure situations (high, medium, low) among coking workers. The high exposure group (n = 23) worked topside of the oven. The medium exposure group (n = 44) worked at the sideoven for more than 4 hr/day, whereas the low exposure group (n = 21) worked at the sideoven for less than 4 hr/day and mostly remained in the control rooms. The low exposure group was used as an internal comparison group. The median BSF concentrations for various exposure situations were as follows, high exposure group: 372 micrograms/m3, medium exposure group: 61 micrograms/m3, low exposure group: 49 micrograms/m3, and referents: 10 micrograms/m3. The coking workers (n = 88) did not significantly differ from the referents (n = 59) in any of the liver function profiles. Excluding the referents, workers in the high exposure group had a mean AST level that was 31% higher (95% confidence interval (CI) = 9-57%) and a mean ALT level that was 46% higher (95% CI = 7-98%) than those in the low exposure group after adjusting for appropriate confounders in multivariate models. The prevalence of an abnormal hepatocellular pattern (AST > 37 IU/L or ALT > 39 IU/L) was more common in the high exposure group than in the low exposure group (adjusted odds ratio = 4.4; 95% CI = 0.9-22.6). However, these associations were not found in GGT, ALP, or BIL. After controlling for the possible effects of nonoccupational factors on serum activity of AST and ALT, we conclude that increased AST and ALT levels among topside coking workers may be caused by heavy inhalation exposure to COE. Additionally, the adverse hepatic effect seems to be caused by a mixture of hazards, rather than a unique identifiable chemical.

Adult↗

PubMed1997

Reduced vascular beta-adrenergic receptors and catecholamine response in rats with lead induced hypertension.

Beta-adrenergic receptor-mediated relaxation of blood vessels declines in lead induced hypertension although the mechanism is unknown. We have utilized the aorta of lead hypertensive rats to investigate this problem. In an effort to elucidate the mechanism responsible for this alteration we examined plasma catecholamine levels, vascular beta-adrenergic receptor density, and cyclic adenosine monophosphate (cAMP) production in lead hypertensive rats. The density of beta-adrenergic receptors was 41% lower in the blood vessels of lead hypertensive rats compared with control rats. The corresponding apparent Kd values were not significantly different between two groups. The plasma catecholamine level was significantly higher in lead hypertensive rats compared with controls (P < 0.001). Stimulation of the vascular beta-adrenoceptor resulted in significantly lower levels of cAMP in lead hypertensive rats compared with controls (P < 0.001). The present results suggest that there is reduced beta-adrenoceptor density and diminished cAMP accumulation in blood vessels from lead hypertensive rats. Plasma catecholamine may play a role in the diminished beta-adrenoceptor and responsiveness to cAMP-mediated vascular relaxation in lead exposure.

Adrenergic beta-Agonists↗

PubMed1997

Characterization of an ATP-dependent DNA ligase encoded by Chlorella virus PBCV-1.

We report that Chlorella virus PBCV-1 encodes a 298-amino-acid ATP-dependent DNA ligase. The PBCV-1 enzyme is the smallest member of the covalent nucleotidyl transferase superfamily, which includes the ATP-dependent polynucleotide ligases and the GTP-dependent RNA capping enzymes. The specificity of PBCV-1 DNA ligase was investigated by using purified recombinant protein. The enzyme catalyzed efficient strand joining on a singly nicked DNA in the presence of magnesium and ATP (Km, 75 microM). Other nucleoside triphosphates or deoxynucleoside triphosphates could not substitute for ATP. PBCV-1 ligase was unable to ligate across a 2-nucleotide gap and ligated poorly across a 1-nucleotide gap. A native gel mobility shift assay showed that PBCV-1 DNA ligase discriminated between nicked and gapped DNAs at the substrate-binding step. These findings underscore the importance of a properly positioned 3' OH acceptor terminus in substrate recognition and reaction chemistry.

Adenosine Monophosphate↗

PubMed1997

A simple surgical treatment for upper lid trichiasis.

The authors report the results of a simple surgical treatment in 24 lids of 19 patients. The most common cause of the trichiasis was trachoma (83.3%). The operation involved splitting the lid margin, fracturing the tarsal plate, and everting sutures. The anatomic success rate was 62.5% and the functional success rate was 75%. Recurrent cilia were mostly isolated and symptomatic improvement was achieved in all but one patient. The authors conclude that this is a cost-effective procedure.

Adult↗

PubMed1997

Changes of hepatitis B markers among young adults in a hepatitis B virus endemic area: a follow up study on medical students.

To elucidate the hepatitis B virus (HBV) infection status of teenagers, to observe changes of the status of these young adults after long-term follow up, to clarify the HBV replication activity of young HBsAg carriers, and to understand the anti-HBs titer of those immune to HBV-infection, a comparison between two health examinations at a 5-or 6-year interval was conducted among 132 medical students. Their ages were 19.1 +/- 0.9 (mean +/- SD). There were 19 (14.4%) HBsAg carriers, 57 (43.2%) immune to HBV infection, and 56 (42.4%) susceptible to HBV. All 19 HBsAg positive carriers were still in carrier status in the second examination. Twelve (63.1%) of the HBV carriers had already HBeAg negative seroconversion before the age of 25. And two carriers might be in the late e seroconversion phase. One susceptible student had a subclinical HBV infection during his university life, with an incidence of HBV infection of 0.47% (1/213) per person-year. Nine (11%) of 82 HBV-immune students had lower anti-HBs concentrations. Six of the 9 students were immunized by natural infection. Anamnestic response developed after booster vaccination. This study shows that these young adults have an HBsAg-carrier rate similar to the general adult population in Taiwan. However, HBeAg seroconversion occurs more often and earlier in this particular population than previous reports have indicated. Moreover, only 24 (40%) susceptible subjects received HBV vaccination after the first recommendation and it is necessary to be more forceful in recommending prompt vaccination.

Adolescent↗

PubMed1997

[Job strain, social support and mental health: a study on the male heavy manufacturing workers].

OBJECT: The aim of this study is to explore the influence of work experience on workers' psychological function. Specifically, the researchers will examine the effect of job demand, decision latitude, job strain, and social support at worksite on the mental health status of male heavy manufacturing workers. METHOD: By purposive sampling, from October 1994 to March 1995, the present investigators implemented a self-administered questionnaire survey on the workers in southern Taiwan. The Karasek job strain model and its measure were embedded in the questionnaire to evaluate workers' perceptions of their job conditions. In addition, Chinese Health Questionnaire (CHQ) was utilized to evaluate the workers' status of mental health. RESULT: Totally, 1,117 workers were selected for this survey. An unviriate analysis showed the younger the workers, the lower their monthly income, and the newer their employment, were more likely to be classified as high risk in mental health status. The workers with more decision latitude and higher social support would be better in mental health status. In addition, it also showed that workers under high job strain were more likely to be in poor mental health status. Result from multivariate logistic regression showed those who served longer, had more decision automony, and had higher social support, were less likely to be in poor mental health status. Instead, those who sustained high job strain were more likely to be in poor mental health status. DISCUSSION: The implication from those findings for the implementation of health promotion program. would be raised, and the limitation of this inference would also be discussed.

Adolescent↗