1.Quantitative Analysis of Quartz, Mica, and Feldspar in Respirable Coalmine Dust in Taebaek Area by Fourier Transform Infrared Spectrophotometry.
Ho Chun CHOI ; Yong Hee CHEON ; Hae Jeong KIM ; Jeong Joo LEE
Korean Journal of Preventive Medicine 1988;21(2):271-283
A Fourier transform infrared spectrophotometric method was described for the determination of quartz, mica(sericite) and feldspar(potassium feldspar) in respirable dust in Taebaek area. The results were as follows; 1) The concentration of minerals were determined from the intensity of absorption peak of quartz at 799 cm-1, sericite at 539 cm-1, and potassium feldspar at 648 cm-1 respectively. 2) The precision(C. V. %) for the quartz determination was 7.70+/-2.68 % from 10 to 200 microgram of quartz. 3) The precision for the sericite determination was 16.34+/-6.82 % from 30 to 500 microgram of serictite. 4) The precision for the potassium feldspar determination was 5.28+/-1.74 % from 30 to 500 microgram of potassium feldspar. 5) The concentration of respirable dust in Taebaek area was 4.90+/-3.29 mg/m3(0.4-93.7%), percent quartz was 1.80+/-4.14% (0.01-20.56%), percent sericite was 11.37+/-6.43% (0.00-29.69%), percent potassium feldspar was 8.15 % (n=7, 3.41-19.70%). 6) The difference of respirable coal dust, quartz, and sericite concentration in drilling, coal cutting, hauling and separating was significant respectively (p<0.05).
Absorption
;
Coal
;
Dust*
;
Fourier Analysis*
;
Minerals
;
Potassium
;
Quartz*
;
Spectrophotometry, Infrared*
2.The comparative study of distortion of untreated cartilages and lyophilized cartilages.
Doo Young OH ; Jeong Hoon KANG ; Hae Cheon CHOI ; Kun Chul YOON
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1998;25(6):949-954
Human untreated costal cartilage was compared with lyophilized human costal cartilage which was treated with defatting solution for 48 hours and freeze drying for 72 hours (-70degree C, 10??bar) on the tendency of distortion. All cartilages, which were taken from six cadavers, were carved 5x5x30mm in size on principle of the balanced cross section. Their distortions were evaluated by two methods at intervals of one week, one month, three months, six months after experiment. At first, the degree of distortion was grossly graded with four steps: grade O; no distortion / grade I; minimal distortion / grade II; moderate distortion / grade III; severe distortion. Second method is measurement and quantification of distortion in the horizontal and vertical plane of cartilage.Untreated cartilage is shown to be an unsatisfactory material, with only three(12%) of the 25 cartilages being cosmetically acceptable(grade 0 and 1) after 6 months. In lyophilized cartilage, 18(94%) of the 19 cartilages were cosmetically acceptable(grade 0 and 1) at 6 months. This figure is highly significant(p<0.01). In another method, distortion in the horizontal(h) and vertical (v) planes of cartilage were measured, and mean values of ???? were calculated. In untreated group, the mean values of ???? were 0.82 at 1 week, 0.91 at 1 month, 1.13 at 3 months, and 1.31 at 6 months. In lyophilized group, the mean values were 0.27 at 1 week, 0.29 at 1 month, 0.40 at 3 months and 0.47 at 6 months. All values were statistically significant(p<0.01).
Cadaver
;
Cartilage*
;
Freeze Drying
;
Humans
3.Free muscle flap reconstruction following resection of the skull base tumour.
Hae Cheon CHOI ; Sang Hoon HAN ; Kyung Suck KOH ; Kun Chul YOON ; Bok Sung CHUNG
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1993;20(6):1257-1265
No abstract available.
Skull Base*
;
Skull*
4.Quartz Concentration and Respirable Dust of Coal Mines in Taeback and Kangneung Areas.
Ho Chun CHOI ; Yong Hee CHEON ; Young No YOON ; Hae Jeong KIM
Korean Journal of Preventive Medicine 1987;20(2):261-269
In order to investigate working conditions of underground coal mines, this work was undertaken to evaluate the respirable dust and the concentration of quartz in Taeback and Kangneung areas. The concentration of quartz was determined by Fourier Transform Infrared Spectrophotometry. The results were as follows; 1) The concentration of respirable dust of drilling and coal face in Taeback and Kangneung areas were as followed. 2) Distribution of respirable dust was well fitted to the long-normal distribution and geometric mean value was log(-1) 0.37+/-log(-1) 0.47 (2.34+/-2.95) mg/m3. 3) The difference of respirable dust concentrations in Taeback and Kangneung areas was not significant statistically (p>0.05). 4) The concentration of quartz of drilling and coal face in Taeback and Kangneung areas were as followed. 5) Distribution of quartz concentrations was well fitted to the log-normal distribution and geometric mean value was log(-1) 0.33+/-log(-1) 0.45 (2.14+/-2.82)%. 6) The difference of quartz concentrations in Taeback and Kangneung areas was not significant (p>0.05), but significant at drilling sites and coal faces (p<0.05).
Coal*
;
Dust*
;
Fourier Analysis
;
Gangwon-do*
;
Quartz*
;
Spectrophotometry, Infrared
5.The Differential Manifestation of Alcohol Withdrawal Symptoms Related to GABAAalpha6 Polymorphism.
Doug Hyun HAN ; Jung Eun CHOI ; Byung Young LEE ; Young Hoon KIM ; Hae Won KIM ; Hye Kyung LEE
Journal of Korean Neuropsychiatric Association 2005;44(2):191-197
INTRODUTION: The gamma-aminobutyric acid type A (GABAA) receptor is an important pharmacological target of alcohol. The phamacological characteristics of the receptor are largely determined by its subunit composition. Compared with all other alpha subtypes, the alpha6- containing receptors are more sensitive to GABA and less sensitive to benzodiazepines. The purpose of this study was to address a role for GABAAalpha6 receptor subunit gene in the development of alcohol dependence. The differential manifestation of alcohol withdrawal symptoms related to GABAAalpha6 polymorphism in patients treating with benzodiazepines was also examined. METHODS: Eighty-seven inpatients with alcohol dependence, and sixty healthy controls were evaluated using CIWA-Ar scale. Each patient was genotyped for GABAAalpha6 subunit. Association between GABAAalpha6 polymorphism and severity of withdrawal symptom were determined. RESULTS: No significant difference was found in GABAAalpha6 receptor genetic type and allelic distribution between the alcohol dependent and control subject. Tremor was more severe in CC than TT type. TT type had higher degree of anxiety, agitation and headache than CC type. The GABAAalpha6 C allele increased the average score of tremor significantly, and T allele increased that of agitation. CONCLUSION: The results suggested that GABAAalpha6 genetic polymorphism was not associated with alcohol dependence and with severity of alcohol withdrawal symptoms. But in benzodiazepine treated patients, GABAAalpha6 polymorphism and allelic type show the difference in severity of each withdrawal symptom. These differences of severity are partly responsible for the unique pharmacological properties associated with the GABAAalpha6 subunit.
Alcoholism
;
Alleles
;
Anxiety
;
Benzodiazepines
;
Dihydroergotamine
;
gamma-Aminobutyric Acid
;
Headache
;
Humans
;
Inpatients
;
Polymorphism, Genetic
;
Receptors, GABA
;
Substance Withdrawal Syndrome*
;
Tremor
6.Epidemiology and Clinical Characteristics of Enterovirus Infections in Children: A Single Center Analysis from 2006 to 2010.
In Soo PARK ; Hae Sung LEE ; Soo Han CHOI ; Hye Jin KIM ; Seo Yeon HWANG ; Doo Sung CHEON ; Jin Keun CHANG
Korean Journal of Pediatric Infectious Diseases 2013;20(2):81-88
PURPOSE: This study was performed to investigate the epidemiology of enterovirus (EV) infections in children at a secondary hospital during recent 5 years. METHODS: We collected the cerebrospinal fluid, stool and throat swab samples from the pediatric patients with suspected EV infections in KEPCO Medical Center, Seoul, Korea from July 2006 to September 2010. EV detection and genotype identification were performed by RT-PCR at Korea Centers for Disease Control and Prevention. RESULTS: A total of 386 samples were collected from 277 patients during study period. Ninety-eight patients (35.4%) were diagnosed with EV infections. The RT-PCR positive rate was the highest in throat swab samples (48.3%). The median age of patient was 4.7 years (range, 0.1-12.5 years). Aseptic meningitis (50, 51.0%) was the most common clinical manifestation; herpangina (22, 22.4%) and hand-foot-mouth disease (18, 18.4%). One hundred EVs were isolated from 98 patients and 20 genotypes of EV were identified; Echovirus 30 (28 cases, 28%), Enterovirus 71 (12 cases, 12%), Echovirus 25 (10 cases, 10%), Echovirus 9 (9 cases, 9%) and Coxsackievirus A6 (8 cases, 8%). Aseptic meningitis caused by Echovirus 30 was the most common manifestation in 2008. There was no complicated case caused by Enterovirus 71. CONCLUSION: This study showed the epidemiology of confirmed EV infection in children from 2006 to 2010. There is a need for continuous surveillance of EV infections and its clinical manifestations.
Centers for Disease Control and Prevention (U.S.)
;
Child
;
Echovirus 9
;
Enterovirus
;
Enterovirus B, Human
;
Enterovirus Infections
;
Genotype
;
Herpangina
;
Humans
;
Korea
;
Meningitis, Aseptic
;
Pharynx
7.Correlation between Mirror Movements and Recovery of Motor Power in Stroke Patients.
Ki Jong PARK ; Nack Cheon CHOI ; Nam Gon KIM ; Hae Jeong YUN ; Joon Gy HONG ; Oh Young KWON ; Byeong Hoon LIM
Journal of the Korean Neurological Association 1998;16(6):794-801
BACKGROUND: Mirror movement is common in young children, and it could be seen in normal adults. Several mechanisms including motor pathway reorganization involved in motor recovery after stroke. Motor pathway reorganization has been reported to be a mechanism in several studies of patients with mirror movement. However, the correlation of motor recovery and mirror movement has been debated. We studied the degree of mirror movement in stroke patients compared with a controlled group to look into their relationship. METHODS: Our controls were 50 adults without neurologic symptoms and signs. The hemiparetic group was comprised 94 patients who had incurred unilateral brain lesion: 36 patients were acute stroke patients, 58 patients were chronic stroke patients. Mirror movements were assessed by three different tasks: abduction of thumb, sequential finger tapping, and grasping. We analyzed mirror movements in controls and patients, and tried to find a correlation between the degree of mirror movement and the recovery of motor power in chronic stroke patients. RESULTS: In controls, male exhibited more frequent mirror movement than female at specific tasks, and there was no difference between tasks of right or left hand. In stroke patients, there was more mirror movement in the nonparetic hand than in the paretic one during the movement of contralateral hand. In acute stroke, the frequency of mirror movement had no variability according to the degree of motor power. The recovery of motor power at a late stage was not correlated with the degree of mirror movement. Consclusions: Motor pathway reorganization seems to be insignificant for motor recovery because the degree of mirror movement was not correlated with the recovery of motor power in this study.
Adult
;
Brain
;
Child
;
Female
;
Fingers
;
Hand
;
Hand Strength
;
Humans
;
Male
;
Neurologic Manifestations
;
Stroke*
;
Thumb
8.Radiologic Localization and Lengths of Umbilical Artery Catheter to Major Aortic Branches Determined by Ultrasonography in Neonates.
Byoung Min CHOI ; Hae Won CHEON ; Kee Hwan YOO ; Young Sook HONG ; Joo Won LEE ; Soon Kyum KIM
Journal of the Korean Society of Neonatology 1999;6(2):225-233
PURPOSE: Incorrect positioning of umbilical artery catheter (UAC) results in an increased incidence of complications and erroneous pressure measurements. We radiologically localized major aortic branches and calculated the length of catheter from umbilicus to celiac artery, renal artery and aortic bifurcation for optimal positioning of UAC. To determine the neonatal body measurement that best predicts optimal UAC lengths, we studied three commonly used parameters-birth weight (BW), total body length (TBL) and shoulder-umbilicus length (SUL). METHODS: Fifty one high type of UAC were routinely identified by sonographic scanning from the epigastrium in longitudinal projection and 42 low type of UAC from the flank in coronal projection. The distances from the catheter tip to the celiac artery, the renal artery and to the aortic bifurcation were measured by electronic calipers and were compared with the length of the catheter from umbilicus to the tip on the chest anteroposterior radiograph. RESULTS: The celiac arteries originated from T10-T12, renal arteries Ll-L2, and aortic bifurcations L3-L5. There was positive correlation between BW, TBL or SUL and the length of catheter to the celiac artery (r2=0.476, 0.749 or 0.753), to the renal artery (r2= 0.785, 0.847 or 0.720), and to the aortic bifurcation (r2=0.714, 0.809 or 0.747). CONCLUSION: Although any one of the three parameters can be used clinically, we prefer the TBL and SUL parameters for its reliability and usefulness in emergency settings. The use of a new distribution plot of origins of major branches and regression equations for calculation of the lengths may help deciding the optimal position of UAC.
Catheters*
;
Celiac Artery
;
Emergencies
;
Humans
;
Incidence
;
Infant, Newborn*
;
Renal Artery
;
Thorax
;
Ultrasonography*
;
Umbilical Arteries*
;
Umbilicus
9.Correction: Trismus Due to Bilateral Coronoid Hyperplasia.
Moon Gi CHOI ; Dong Hyuck KIM ; Eun Jung KI ; Hae Myung CHEON
Maxillofacial Plastic and Reconstructive Surgery 2014;36(5):237-237
The authors would like to delete the acknowledgement part.
10.Plasma Atrial Natriuretic Peptide and Hemodynamic Change of Patent Ductus Arteriosus in Healthy Low Birth Weight Infants without Clinical Evidence of PDA.
Byoung Min CHOI ; Jong Kwnag LEE ; Hae Won CHEON ; Kee Hwan YOO ; Young Sook HONG ; Joo Won LEE ; Soon Kyum KIM
Journal of the Korean Society of Neonatology 1999;6(1):43-51
PURPOSE: Atrial natriuretic peptide(ANP) is a hormone with strong vasodilating, diu-retic and natriuretic properties. The aim of this study was to clarify the interrelationship of ANP secretion and hemodynamic changes of patent ductus arteriosus(PDA) in healthy preterm and fullterm infants without clinical evidence of PDA. METHODS: Thirteen preterm infants and six full term infants who did not develop clinical evidence of PDA were studied at 6 hr, 12 hr, 24 hr, 3rd day and 4th day after birth, until their PDAs closed spontaneously. Plasma ANP concentrations and the hemodynamic changes of PDA were rneasured. RESULTS: The ANP concentrations of all infants increased from 34.1+/-10.9 pg/ml at 6 hr to 120.5+/-18.8 pg/ml at 12 hr, and declined thereafter gradually to 74.2+/-12.7 pg/ml at 4th day. The ANP concentrations, LA/Ao ratio and LAV decreased after ductal closure. The pulmonary flow velocity(PFV) of PDA correlated with ANP concentration in preterm infants(r=0.23, P<0.05). LA/Ao ratio correlated with ANP contration in all infants (r=0.28, P<0.05), especially in preterm infants(r=0.46, P<0.01 during 12 hr and 4th day after birth. LAV correlated with the ANP concentrations in preterm infants during 12 hr and 4th day after birth(r=0.34, P<0.05). CONCLUSION: The changes of ANP concentrations are probably due to the changes of the left-to-right shunt of PDA with left atrial stretch. Reduction of the ANP concentrations may serve as an indicator of spontaneous closure of PDA. Therefore ANP measurement may be useful in deciding the need and the timing of medical and surgical managernent of newbom infants without clinical evidence of PDA.
Atrial Natriuretic Factor
;
Ductus Arteriosus, Patent*
;
Hemodynamics*
;
Humans
;
Infant*
;
Infant, Low Birth Weight*
;
Infant, Newborn
;
Infant, Premature
;
Parturition
;
Plasma*