Biomedical subjects

Jae-Wook Choi

Publications and source records attributed to Jae-Wook Choi.

4 recordsLinked to original sources

PubMed2006

Gliding arc plasma processing of CO2 conversion.

Conversion of carbon dioxide (CO2) using gliding arc plasma was performed. The research was done to investigate the effect of variation of total gas flow rates and addition of auxiliary gases--N2, O2, air, water--to the CO2 conversion process. This system shows higher power efficiency than other nonthermal plasma methods. Experiment results indicate the conversion of CO2 reaches 18% at total gas flow rate of 0.8 L/min and produces CO and O2 as the main gaseous products. Among auxiliary gases, only N2 gives positive effect on CO2 conversion and the power efficiency at N2 concentration of 95% and total gas flow rate of 2 L/min increases about three times compared to pure CO2 process.

Air Pollutants↗

PubMed2003

Increase of olfactory threshold in plating factory workers exposed to chromium in Korea.

To disclose the effects of chromium (Cr) on olfactory function, olfactory threshold tests were conducted on 27 male plating workers (Cr workers) with signs and symptoms of olfactory irritation but without nasal septum perforation or ulcer and on 34 male control subjects in Korean plating factories. The Cr workers had been exposed to Cr fume for 0.9 to 18.2 (mean 7.9) years; their blood Cr concentrations (0.16-3.69, mean 1.29 microg/dl) were significantly higher than those of the 34 control subjects (0.04-1.95, mean 0.55 microg/dl). Scores on recognition thresholds among the Cr workers were significantly higher than those of the control subjects (p < 0.05) and related positively and significantly to the exposure periods of the 27 Cr workers (p < 0.05). Olfactory thresholds were not significantly different between the Cr workers with and without nasal signs or symptoms, except that the scores on the recognition threshold were significantly higher in those experiencing difficulty with smell (p < 0.05). It is suggested that olfactory threshold is affected by Cr without development of nasal septum perforation or ulceration.

Adult↗

PubMed2002

Influence of polymorphism of GSTM1 gene on association between glycophorin a mutant frequency and urinary PAH metabolites in incineration workers.

The association between urinary 1-hydroxypyrene glucuronide (1-OHPG) levels, as an internal measure of polycyclic aromatic hydrocarbon (PAH) exposure, and glycophorin A (GPA) mutation frequency, as an early biologic effect indicator, was determined to establish whether genetic polymorphisms of glutathione S-transferase (GST) isoforms GSTM1 and GSTT1 play a role. Eighty-one workers including 38 employees directly involved in incinerating industry wastes were recruited from a company located in South Korea. Urinary 1-OHPG levels were measured by synchronous fluorescence spectroscopy after immunoaffinity purification using monoclonal antibody 8E11. Erythrocyte GPA variant frequency (NN or NO) was assessed in MN heterozygotes with a flow cytometric assay. The GSTM1 and GSTT1 genotypes were assessed by a multiplex polymerase chain reaction (PCR) method. Urinary 1-OHPG levels were higher in workers handling industrial wastes than in those with presumed lower exposure to PAHs. An increase was seen in GPA variant frequency levels with increase in urinary 1-OHPG levels. When this association was evaluated by GSTM1 genotype status, the association between GPA mutation and urinary 1-OHPG levels was stronger in individuals with GSTM1 genotype. These results suggest that the association between urinary 1-OHPG and GPA mutation might be modulated by the GSTM1 genotype.

Adult↗

PubMed2002

Skin disease among staff in a large Korean nursing home.

Although previous studies have documented reasonably high rates of skin disease among nursing home staff, the prevalence among Korean workers is not well known. For this investigation we selected a large Korean nursing home and distributed a skin disease questionnaire to all staff. Questions included job title, job description, employment history, working hours, patient contact and the occurrence of skin disease over the past 12 months. Workers who reported a dermatological problem then underwent skin examinations conducted by specialist occupational physicians and a dermatologist. Contact dermatitis was the most common skin disease detected, with 4.8% of staff currently suffering from it and 6.0% reporting it in the previous 12-month period. Tinea pedis was another common condition, affecting 3.6% on our examination day. However, only two-thirds of them (2.4%) recounted a past history of tinea pedis. Scabies was diagnosed among 2.4% of staff and reported as a previous infection by 6.0%. Overall, the prevalence of dermatitis and scabies were quite low when compared to previous studies, while fungal infection rates were similar to other investigations. Further research into this growing occupational demographic is indicated.

Adult↗