1.Ambient Noise Levels in the Audiometric Test Rooms Used for Special Periodic Health Examination.
Kyoo Sang KIM ; Yong Hyu CHOI ; Yong Lim WON ; Seong Kyu KANG
Korean Journal of Occupational and Environmental Medicine 2004;16(3):316-328
OBJECTIVES: The ambient noise levels in the test rooms affect the workers's hearing threshold. The present study was designed to assess the ambient noise levels in the test rooms to determine if valid hearing tests, both pure-tone air conduction and bone-conduction, could be performed in these environments. METHODS: In the present study, third octave band ambient noise sound pressure levels were measured in 124 audiometric test rooms used for clinical audiometry, and the results were compared with the ANSI third octave band maximum permissible ambient noise levels (MPANLs) for each test condition and frequency range. RESULTS: The ambient noise SPLs were highest in the lower frequencies, and this decreased as the frequency increased. For the "ears covered"condition, about 24.2% of the rooms were in compliance (pass) with the MPANLs for the 125-8000 Hz, 35.5% were in compliance for the 250-8000 Hz range and 55.6% were in compliance for the 500-8000 Hz range. For the "ears not covered"condition, only about 8.1% of the rooms passed for the 125-8000 Hz, 13.7% of the rooms passed for the 250-8000 Hz range and 34.7% of the rooms passed for the 500-8000 Hz range. All 124 rooms met the OSHA MPANLs. CONCLUSIONS: The results of this study strongly indicate that clinical audiometry is being conducted in test rooms having unacceptable or excessive ambient noise levels.
Audiometry
;
Compliance
;
Hearing
;
Hearing Tests
;
Noise*
;
United States Occupational Safety and Health Administration
2.Analysis of Work-Related Musculoskeletal Disease by Approved Korea Labor Welfare Corporation in 1999.
Yeon Soon AHN ; Yong Hyu CHOI ; Seong Kyu KANG ; Ho Keun CHUNG
Korean Journal of Occupational and Environmental Medicine 2002;14(2):154-168
OBJECTIVES: The purpose of this study was to analyze the characteristics of workrelated musculoskeletal diseases, as listed by the Korea Labor Welfare Corporation (KLWC). METHODS: Using the database of the KLWC, we collected information from 410 approved occupational musculoskeletal disease cases, which occurred between 1 January and 31 December 1999 and were approved by 30 June in 2000. We investigated the characteristics of the disease using a mail survey and telephone interviews. The characteristics we investigated included : sex, age, disease-related working duration, process of disease occurrence, type of enterprises, etc. RESULTS: Men accounted for 75.6 % (310 workers) of the approved cases. The most common age group was 30-39 years (n=143, 34.9 %). The mean disease-related working duration was 5.7 years, and the most commonly had a work-duration of 1-5 years (n=108, 36.0 %). The major industrial types of enterprise were manufacturing (235 workers, 57.3 %), transportation (46 workers, 11.2 %), and construction (25 workers, 6.1 %). Within the manufacturing industry, the most common was motor vehicles and trailers manufacturing. Within the group, the most common jobs were plant or machine operators and assemblers (129 workers, 36.5 %), elementary occupations (90 workers, 25.5 %), and craft and related trades workers (63 workers, 17.8 %). The majority of the diseases involved lumbar problems (232 cases, 54.7 %), neck and upper extremity diseases (183 cases, 43.2 %) and lower extremity diseases (9 cases, 2.1 %). In the cases of lumbar disease, the mean age and working duration was 36.5 years and 4.7 years, respectively. Fifty-four cases of lumbar diseases were due to repetitive work and 89 due to non-repetitive work. Bad posture at work was the most common cause for those doing repetitive work(23 cases), and lifting the most common cause of problems in the non-repetitive work cases (27). CONCLUSIONS: We were able to elucidate the characteristics of workers with approved occupational musculoskeletal disease through this study. Many approved cases occurred in women, and workers performing repetitive work, of these herniated nucleus pulposus occurred in many workers performing simple repetitive works without serious external forces. This suggests that a prevention policy for occupational musculoskeletal disease must be established, to focusing on the above-mentioned high-risk groups.
Female
;
Humans
;
Interviews as Topic
;
Korea*
;
Lifting
;
Lower Extremity
;
Male
;
Motor Vehicles
;
Musculoskeletal Diseases*
;
Neck
;
Occupations
;
Plants
;
Postal Service
;
Posture
;
Transportation
;
Upper Extremity
3.Change on Lens Accomodation and Pupil Light Reflex in VDT works.
Euna KIM ; Yang Ho KIM ; Young Woo JIN ; Chang Ho CHAI ; Yong Hyu CHOI ; Young Hahan MOON
Korean Journal of Preventive Medicine 1997;30(3):599-608
We studied on change of lens accommodation and pupil light reflex caused by VDT work in six women and compared them with those of other office works. The results were as follows. 1. In VDT work group, the accommodation contraction velocity decreased during the first 2-hr VDT task, then recovered markedly by the end of the one-hour lunch break, and then decreased again by the end of the 2nd 2-hr VDT task. Changes of relaxation velocity showed similar pattern although it was less typical than that of contraction velocity. 2. There was no marked change in accommodation contraction velocity and amplitude of accommodation in general office work group and near-distance office work group, and in the near-distance office work accommodation relaxation velocity decreased according to work load without recovery after lunch break. 3. Initial pupil diameter, initial pupil area of light reflex decreased significantly during VDT task only in VDT work group, and didn't recover after lunch break. These results suggest possibility that changes of accommodation contraction velocity, accommodation relaxation velocity, near point distance, and pupil diameter and area are useful in evaluating characteristics of VDT work. For this, more research adjusted individual differences, circadian rhythm, emotional stress needs.
Accommodation, Ocular
;
Circadian Rhythm
;
Female
;
Humans
;
Individuality
;
Lunch
;
Pupil*
;
Reflex*
;
Relaxation
;
Stress, Psychological
4.Clinical Analysis of Posterior Fossa Tumors.
Yong Tae JEONG ; Byung Ook CHOI ; Soo Chun KIM ; Hyung Dong KIM ; Soo Hyu KIM ; Jae Hong SHIM
Journal of Korean Neurosurgical Society 1987;16(3):571-580
We analyzed the 43 cases of the posterior fossa tumors at the Busan Paik Hospital, Inje Medical College from January 1980 to December 1986. The posterior fossa tumors included 12 cases of cerebellar astrocytoma, 10 cases of acoustic neurinoma, 5 cases of medulloblastoma, 5 cases of brain stem glioma, 2 cases of meningioma, 2 cases of hemangioblastoma, 2 cases of tuberculoma, 1 case of glioblastoma multiforme, 1 case of oliodendroglioma, 1 case of rhabdomyosarcoma, 1 case of glomus jugulare tumor and 1 case of arteriovenous malformation. The posterior fossa tumors were occupied on the cerebellar hemisphere in 18 cases, the cerebellar vermis in 8 cases, the cerebellar pontine angle in 12 cases and the brain stem in 5 cases. The 25 cases out of the 43 cases of the posterior fossa tumors were accompanied with hydrocephalus. The 10 cases received the radiation therapy and/or the chemotherapy after operation. After treatment of the posterior fossa tumors, 52.6% favorable outcome, 34.2% unfavorable outcome and 13.2% mortality were estimated.
Arteriovenous Malformations
;
Astrocytoma
;
Brain Stem
;
Busan
;
Drug Therapy
;
Glioblastoma
;
Glioma
;
Glomus Jugulare Tumor
;
Hemangioblastoma
;
Hydrocephalus
;
Infratentorial Neoplasms*
;
Medulloblastoma
;
Meningioma
;
Mortality
;
Neuroma, Acoustic
;
Rhabdomyosarcoma
;
Tuberculoma
5.An Evaluation for the Occupational Distribution of Carpal Tunnel Syndrome Diagnosed at a University Hospital.
Yong Hyu CHOI ; Seong Kyu KANG ; Chang Ho CHAE ; Jong Han LEEM ; Chung Yill PARK
Korean Journal of Occupational and Environmental Medicine 1999;11(3):313-322
OBJECTIVES: The study was carried out to evaluate the work-relatedness and the occupational distribution in 147 carpal tunnel syndrome(CTS) cases diagnosed at a university hospital from May 1996 to May 1998. METHODS: We obtained the information on disease appearance, occupational history including job content and other life style by medical records and telephone interviews. RESULTS: Of the 147 patients with carpal tunnel syndrome, 51 patients(34.7 %) were shown to be work-related. Work-related CTS were most frequent in elementary workers (21 case, 41.2%). The other eases were 15(29.4%) workers in service and shop and market sales, 9(17.6%) workers in craft and related traders, 4(7.8%) workers in skilled agriculture and fishery. Only two workers had claimed to the Industrial Accident Compensation Insurance, but no one has been admitted as an occupational CTS yet. CONCLUSIONS: It is suggested that arrangements of surveillance system for adequate control of occupational CTD is neccessity.
Accidents, Occupational
;
Agriculture
;
Carpal Tunnel Syndrome*
;
Commerce
;
Compensation and Redress
;
Fisheries
;
Humans
;
Insurance
;
Interviews as Topic
;
Life Style
;
Medical Records
6.Characterization of a conjugated polysuccinimide-carboplatin compound
Sun Young LEE ; Chang Hoon CHAE ; Miklós ZRÍNYI ; Xiangguo CHE ; Je Yong CHOI ; Dong-Hyu CHO
The Korean Journal of Physiology and Pharmacology 2023;27(1):31-38
Carboplatin, an advanced anticancer drug with excellent efficacy against ovarian cancer, was developed to alleviate the side effects that often occur with cisplatin and other platinum-based compounds. Our study reports the in vitro characteristics, viability, and activity of cells expressing the inducible nitric oxide synthase (iNOS) gene after carboplatin was conjugated with polysuccinimide (PSI) and administered in combination with other widely used anticancer drugs. PSI, which has promising properties as a drug delivery material, could provide a platform for prolonging carboplatin release, regulating its dosage, and improving its side effects. The iNOS gene has been shown to play an important role in both cancer cell survival and inhibition. Herein, we synthesized a PSI-carboplatin conjugate to create a modified anticancer agent and confirmed its successful conjugation. To ensure its solubility in water, we further modified the structure of the PSI-carboplatin conjugate with 2-aminoethanol groups. To validate its biological characteristics, the ovarian cancer cell line SKOV-3 and normal ovarian Chinese hamster ovary cells were treated with the PSI-carboplatin conjugate alone and in combination with paclitaxel and topotecan, both of which are used in conventional chemotherapy. Notably, PSI-carboplatin conjugation can be used to predict changes in the genes involved in cancer growth and inhibition. In conclusion, combination treatment with the newly synthesized polymer-carboplatin conjugate and paclitaxel displayed anticancer activity against ovarian cancer cells but was not toxic to normal ovarian cancer cells, resulting in the development of an effective candidate anticancer drug without severe side effects.
7.Development of Porcine Pericardial Heterograft for Clinical Application(Microscopic Analysis of Various Fixation Methods).
Kwan Chang KIM ; Chang Hyu CHOI ; Chang Ha LEE ; Chul LEE ; Sam Sae OH ; Seongsik PARK ; Woong Han KIM ; Kyung Hwan KIM ; Yong Jin KIM
The Korean Journal of Thoracic and Cardiovascular Surgery 2008;41(3):295-304
BACKGROUND: Various experimental trials for the development of bioprosthetic devices are actively underway, secondary to the limited supply of autologous and homograft tissue to treat cardiac diseases. In this study, porcine bioprostheses that were treated with glutaraldehyde (GA), ethanol, or sodium dodecylsulfate (SDS) were examined with light microscopy and transmission electron microscopy for mechanical and physical imperfections before implantation. MATERIAL AND METHOD: 1) Porcine pericardium, aortic valve, and pulmonary valve were examined using light microscopy and JEM-100CX II transmission electron microscopy, then compared with human pericardium and commercially produced heterografts. 2) Sections from six treated groups (GA-Ethanol, Ethanol-GA, SDS only, SDS-GA, Ethanol-SDS-GA and SDS-Ethanol-GA) were observed using the same methods. RESULT: 1) Porcine pericardium was composed of a serosal layer, fibrosa, and epicardial connective tissue. Treatment with GA, ethanol, or SDS had little influence on the collagen skeleton of porcine pericardium, except in the case of SDS pre-treatment. There was no alteration in the collagen skeleton of the porcine pericardium compared to commercially produced heterografts. 2) Porcine aortic valve was composed of lamina fibrosa, lamina spongiosa, and lamina ventricularis. Treatment with GA, ethanol, or SDS had little influence on these three layers and the collagen skeleton of porcine aortic valve, except in the case of SDS pre-treatment. There were no alterations in the three layers or the collagen skeleton of porcine aortic valve compared to commercially produced heterografts. CONCLUSION: There was little physical and mechanical damage incurred in porcine bioprosthesis structures during various glutaraldehyde fixation processes combined with anti-calcification or decellularization treatments. However, SDS treatment preceding GA fixation changed the collagen fibers into a slightly condensed form, which degraded during transmission electron micrograph. The optimal methods and conditions for sodium dodecylsulfate (SDS) treatment need to be modified.
Aortic Valve
;
Bioprosthesis
;
Collagen
;
Connective Tissue
;
Electrons
;
Ethanol
;
Glutaral
;
Heart Diseases
;
Humans
;
Light
;
Microscopy
;
Microscopy, Electron
;
Microscopy, Electron, Transmission
;
Pericardium
;
Pulmonary Valve
;
Skeleton
;
Sodium
;
Transplantation, Heterologous
;
Transplantation, Homologous
8.Prevalence of Occupational Asthma and Exposure Level of Pharmaceutical Dust of Workers in a Pharmaceutical Company.
Sung Soo OH ; Yong Hyu CHOI ; Eun A KIM ; Young Mok LEE ; Jae Kil JANG ; Jang Jin YOO ; Seung Hyun PARK ; Soo Young JUNG ; Tae Kyun KIM ; Kyoo Sang KIM ; Seong Kyu KANG
Korean Journal of Occupational and Environmental Medicine 2006;18(2):94-102
OBJECTIVES: After the investigation of one worker with occupational asthma, we surveyed the prevalence of occupational asthma and the exposure level of pharmaceutical dust of 32 workers in a pharmaceutical company. METHODS: Thirty-two of the 90 employees participated in the survey which consisted of questionnaire, blood sampling, spirometry and skin prick tests with 8 common allergens as well as 9 antibiotics and 2 enzymes. Various indices of the working environment were also measured. Subjects who had a symptom suggestive of work-related asthma or positive skin prick test were further investigated by PC20 methacholine. Nine subjects who had a PC20 result of 16 mg/ml or less (n=7) or had work-related symptoms and positive skin prick test (n=2) were referred to undergo a specific bronchial provocation test to pharmaceutical dust in an academic allergic disease center. RESULTS: Eleven of 32 workers (34.4%) had a work-related symptom suggestive of occupational asthma. Ten (31.2%) showed positive skin prick test. 8 (25.0%) had a PC20 result of 16 mg/ml or less (indicative of significant bronchial hyperresponsiveness), and 5 (15.6%) had a positive result on the specific bronchial provocation test. Exposure levels of stuffing, input of raw materials and screening process were relatively high. CONCLUSIONS: This survey showed that pharmaceutical workers have an increased risk of occupational asthma. Although pharmaceutical factories maintain a relatively good working environment, careful control of respiratory tract exposures, especially during stuffing, input of raw materials and screening process, is important to prevent occupational asthma. Pharmaceutical workers need to undergo regular skin prick and methacholine bronchial provocation tests, as well as asthmatic symptom survey, to ensure the early detection and prevention of occupational asthma.
Allergens
;
Anti-Bacterial Agents
;
Asthma
;
Asthma, Occupational*
;
Bronchial Provocation Tests
;
Dust*
;
Mass Screening
;
Methacholine Chloride
;
Prevalence*
;
Questionnaires
;
Respiratory System
;
Skin
;
Spirometry
9.An Experience of Cox-maze III Procedure for Chronic Atrial Fibrillation.
Sam Hyun KIM ; Yee Tae PARK ; Pil Won SEO ; Sung Sik PARK ; Jae Wook RYU ; Chang Hyu CHOI ; Myung Ae KIM ; Myung Yong LEE ; Young Kwon KIM
The Korean Journal of Thoracic and Cardiovascular Surgery 1998;31(7):668-673
During the past several years, the maze operation has become the most effective method of treatment for chronic atrial fibrillation. When the maze procedure is done concomittantly with other cardiac operations, surgeons, in their initial experiences, may be concerned about the additional operative risks and uncertainty of the results. We performed the Cox-maze III procedure in six cases of chronic atrial fibrillation associated with mitral, mitral & aortic, or coronary arterial disease. Maze III procedure was done with open mitral commissurotomy (3 cases), mitral valve replacement (1 case), aortic and mitral valve replacement (1 case), and two-vessel coronary bypass graft (1 case). In spite of rather prolonged aortic cross clamp time, cardiac recovery was uneventful in all cases. No cases required reexploration for postoperative bleeding. All patients showed regular sinus rhythms immediate or between 2 and 20 days postoperateratively. Transient postoperative supraventricular arrhythmarias were easily controlled by various antiarrhythmic agents. In follow up evaluations, all cases showed regular sinus rhythm on ECG and the right and left atrial transport function was confirmed by Doppler echocardiography in all except one. Though our experience was limited in case number, the Cox-maze III procedure was effective in controlling the chronic atrial fibrillation without serious additional operative risks.
Atrial Fibrillation*
;
Echocardiography, Doppler
;
Electrocardiography
;
Follow-Up Studies
;
Hemorrhage
;
Humans
;
Mitral Valve
;
Transplants
;
Uncertainty
10.Aplastic Anemia in a Petrochemical Plant Worker.
Young Mann BAAK ; Yong Hyu CHOI ; Seong Kyu KANG ; Ji Hong KIM ; Kyoung Ah KIM ; Young LIM ; Joung Wook LEE
Korean Journal of Occupational and Environmental Medicine 1999;11(2):287-292
Aplastic anemia is characterized by pancytopenia with hypocellular bone marrow. Fifty percent of the cases are idiopathic and the rest are caused by various agents including drugs, chemicals, radiation and viruses. It is difficult to link specific etiologic agents, especially chemicals to the development of aplastic anemia because multiple or unknown exposures may be involved in. Benzene, a common industrial chemical and a component of gasoline, may lead progressively to pancytopenia, aplastic anemia and leukemia when exposed. A petrochemical worker with aplastic anemia was referred to our hospital to evaluate a relationship between the job history and the disease. He worked in the petrochemical plant for .21 years and was exposed to low-level benzene. There was not any other etiologic agent except benzene and this is the case report of aplastic anemia which possibly due to benzene exposure.
Anemia, Aplastic*
;
Benzene
;
Bone Marrow
;
Gasoline
;
Leukemia
;
Pancytopenia
;
Plants*