2.Noise-Induced Temporary Threshold Shift and its Recovery in Industry.
Soo Hun CHO ; Mi Na HA ; Sang Hwan HAN ; Young Soo JOO ; Ju Hon SUNG ; Jong Won KANG ; Dork Ro YUN ; Bong Bin SONG ; Myung Hag LEE ; Seon Tae KIM
Korean Journal of Occupational and Environmental Medicine 1996;8(2):320-329
To determine the recovery time from noise-induced temporary threshold shift (TTS), a prospective field study was conducted at three worksites where workers are known to be exposed high level of noise. Subjects were selected according to answers on a questionnaire which inquired about otological history and previous noise exposure, including avocational, military and occupational exposures. After excluding employees with past otologic problems, recent exposure to high level noise, and under medications, total 92 employees participated in the study. Among 92 participants, complete consecutive audiometric examinations were carried out at 0~2 hours, 5~7 hours, 14~16 hours after worktime noise exposure on 26 participants wearing hearing protectors and 22 participants wearing no protective devices. The difference between the hearing level 0~2 hours after noise exposure and 5~7 hours is statistically significant by paired t-test(p<0.01). The median recovery times calculated from the data of 22 participants wearing no protective hearing devices are 15.6 hours at 4000 Hz, and 7.7 hours, 10.3 hours, 8.4 hours at 1000 Hz, 2000 Hz and 8000 Hz respectively. These data suggest that when measuring the pure tone audiometry for noise exposed workers, at least 16 hours noise-free interval is required.
Audiometry
;
Hearing
;
Hearing Loss, Noise-Induced
;
Humans
;
Military Personnel
;
Noise
;
Occupational Exposure
;
Prospective Studies
;
Protective Devices
;
Questionnaires
;
Workplace
3.Noise-Induced Temporary Threshold Shift and its Recovery in Industry.
Soo Hun CHO ; Mi Na HA ; Sang Hwan HAN ; Young Soo JOO ; Ju Hon SUNG ; Jong Won KANG ; Dork Ro YUN ; Bong Bin SONG ; Myung Hag LEE ; Seon Tae KIM
Korean Journal of Occupational and Environmental Medicine 1996;8(2):320-329
To determine the recovery time from noise-induced temporary threshold shift (TTS), a prospective field study was conducted at three worksites where workers are known to be exposed high level of noise. Subjects were selected according to answers on a questionnaire which inquired about otological history and previous noise exposure, including avocational, military and occupational exposures. After excluding employees with past otologic problems, recent exposure to high level noise, and under medications, total 92 employees participated in the study. Among 92 participants, complete consecutive audiometric examinations were carried out at 0~2 hours, 5~7 hours, 14~16 hours after worktime noise exposure on 26 participants wearing hearing protectors and 22 participants wearing no protective devices. The difference between the hearing level 0~2 hours after noise exposure and 5~7 hours is statistically significant by paired t-test(p<0.01). The median recovery times calculated from the data of 22 participants wearing no protective hearing devices are 15.6 hours at 4000 Hz, and 7.7 hours, 10.3 hours, 8.4 hours at 1000 Hz, 2000 Hz and 8000 Hz respectively. These data suggest that when measuring the pure tone audiometry for noise exposed workers, at least 16 hours noise-free interval is required.
Audiometry
;
Hearing
;
Hearing Loss, Noise-Induced
;
Humans
;
Military Personnel
;
Noise
;
Occupational Exposure
;
Prospective Studies
;
Protective Devices
;
Questionnaires
;
Workplace
4.The mRNA expression of MMP-1, TIMP-1, TGF-beta1 in gingival keratocytes from gingival hyperplasia induced by cyclosporine A.
Hag Soo KANG ; Jae Sun LEE ; Jung Ho BING ; Chang Joo PARK ; Jae Jung IM ; Kyung Gyun HWANG ; Kwang Sup SHIM
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2008;34(4):405-411
PURPOSE: Cyclosporine A (CsA) is a versatile immunosuppresive agent used to prevent graft rejection syndrome and treat autoimmune disease. One of the major side effects associated with CsA is the abnormal gingival hyperplasia. The purpose of this study was to investigate the relationship between the mRNA expression of the MMP-1, TIMP-1, and TGF-beta1 and the concentration of CsA in cultured human gingival keratinocytes. MATERIALS AND METHODS: Gingival keratocytes were obtained from gingival tissues of 4 healthy donors. The cultured gingival keratocytes were incubated with increasing concentrations of CsA (0-2000 ng/ml) for 24 hours and the expression of MMP-1, TIMP-1, and TGF-beta1 were determined by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The expressions of MMP-1 and TGF-beta1 were not significantly different according to the concentrations of CsA. The expression of TIMP-1 was significantly increased at the CsA concentration of 500 ng/ml. CONCLUSION: We concluded that the gingival hyperplasia induced by CsA was more related with TIMP-1 than MMP-1 or TGF-beta1 on gingival collagen metabolism in patients treated with CsA.
Autoimmune Diseases
;
Collagen
;
Cyclosporine
;
Gingival Hyperplasia
;
Graft Rejection
;
Humans
;
Keratinocytes
;
RNA, Messenger
;
Tissue Donors
;
Tissue Inhibitor of Metalloproteinase-1
;
Transforming Growth Factor beta1
5.Radiologic Evaluation of Styloid Process by Fuchs' Series.
Hag Jun KIM ; Jang Mook KIM ; Sung Hun KIM ; Soo Hyun PARK ; Byung Don LEE ; Hyuck Soon CHANG ; Ju Won KANG
Korean Journal of Otolaryngology - Head and Neck Surgery 1997;40(5):688-694
Elongated styloid process or ossification of the styloid or stylomandibular ligament is a source of the craniofacial and cervical pain. Most patients with elongated styloid remain asymptomatic but some patients complain of vague facial pain, otalgia, dysphagia and pain along the distribution of internal and external carotid artery. Differential diagnosis from chronic pharyngotonsillitis, trigeminal neuralgia and glossopharyngeal neulagia is difficult. Because that normal length of styloid process was not evaluated and diagnostic criteria was not unclear in Korea, authors measured the length of styloid process in non-symptomatic 60 adults using Fuchs' method. Key words : Styloid process;Fuchs' series
Adult
;
Carotid Artery, External
;
Deglutition Disorders
;
Diagnosis, Differential
;
Earache
;
Facial Pain
;
Humans
;
Korea
;
Ligaments
;
Neck Pain
;
Trigeminal Neuralgia
6.The study of efficiency of corticotomy in treatment of bimaxillary protrusion
Young Jun SEO ; Sung Woo JUNG ; Hag Soo KANG ; Jae Jung IM ; Young Sung HUH ; Soon Seop WOO ; Kwang Sup SHIM ; Kyung Gyun HWANG
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons 2005;27(4):365-371