Association of the Metabolic Syndrome and Bone Mineral Density in Postmenopausal Women / 가정의학회지

BACKGROUND: The metabolic syndrome (MS) is a cluster of risk factors of cardiovascular disease. The association between components of the MS and bone mineral density has been researched, but no prior studies have directly evaluated the association with the metabolic syndrome and bone mineral density in Korea. METHODS: We evaluated postmenopausal women who had visited a university hospital from November 2006 to October 2007. Data on their lifestyle, current medical diseases and medications were collected from medical records. Height, body weight, waist circumference and serum lipid profiles were measured. RESULTS: The prevalence of metabolic syndrome was 21.8% in this study. In adjusted analysis including age and other factors, only waist circumference had a close correlation with bone mineral density of femur and lumbar vertebral body (P < 0.05). The bone mineral density of femur and lumbar vertebral body had no correlation with the presence of metabolic syndrome. When stratified by body mass index, corrected bone mineral density revealed no significant correlation with the presence of metabolic syndrome. CONCLUSION: The bone mineral density of postmenopausal women with metabolic syndrome has highly influenced by obesity, especially by abdominal obesity.

Association of the Metabolic Syndrome and Bone Mineral Density in Postmenopausal Women / 가정의학회지

BACKGROUND: The metabolic syndrome (MS) is a cluster of risk factors of cardiovascular disease. The association between components of the MS and bone mineral density has been researched, but no prior studies have directly evaluated the association with the metabolic syndrome and bone mineral density in Korea. METHODS: We evaluated postmenopausal women who had visited a university hospital from November 2006 to October 2007. Data on their lifestyle, current medical diseases and medications were collected from medical records. Height, body weight, waist circumference and serum lipid profiles were measured. RESULTS: The prevalence of metabolic syndrome was 21.8% in this study. In adjusted analysis including age and other factors, only waist circumference had a close correlation with bone mineral density of femur and lumbar vertebral body (P < 0.05). The bone mineral density of femur and lumbar vertebral body had no correlation with the presence of metabolic syndrome. When stratified by body mass index, corrected bone mineral density revealed no significant correlation with the presence of metabolic syndrome. CONCLUSION: The bone mineral density of postmenopausal women with metabolic syndrome has highly influenced by obesity, especially by abdominal obesity.

The Impact of Functional Constipation on the Quality of Life in the Elderly over 60 Years / 가정의학회지

BACKGROUND: Constipation is one of the most common digestive complaints. Although, there are increased interest on the socioeconomic effect of constipation and studies associated with quality of life on constipation, there is no study about the influence of constipation onto quality of life (QOL) in Korea. We studied the impact of functional constipation on QOL. METHODS: Between March to June 2008, person to person survey with 844 elderly aged over 60 years was performed at two senior care centers, a public health center, and secondary hospital in Seoul metrocity and Chung-ju city. The diagnosis of functional constipation was based on the Rome III criteria and QOL was measured by the Medical Outcomes Study (MOS) 36-Item Short-Form Health Survey (SF-36). RESULTS: The average age was 73.6 years and the prevalence rate of constipation was 20.3%. The average SF-36 score was 63.5 in total population, 57.9 in constipation group, and 64.9 in normal group. CONCLUSION: These results suggest that the constipation lowers QOL in adults aged over 60 years old. Further study will be necessary to explore if QOL changes according to the severity of constipation and its treatment and to assess QOL using a disease-specific measurement tool that can be used for Korean environment.

The Impact of Functional Constipation on the Quality of Life in the Elderly over 60 Years / 가정의학회지

BACKGROUND: Constipation is one of the most common digestive complaints. Although, there are increased interest on the socioeconomic effect of constipation and studies associated with quality of life on constipation, there is no study about the influence of constipation onto quality of life (QOL) in Korea. We studied the impact of functional constipation on QOL. METHODS: Between March to June 2008, person to person survey with 844 elderly aged over 60 years was performed at two senior care centers, a public health center, and secondary hospital in Seoul metrocity and Chung-ju city. The diagnosis of functional constipation was based on the Rome III criteria and QOL was measured by the Medical Outcomes Study (MOS) 36-Item Short-Form Health Survey (SF-36). RESULTS: The average age was 73.6 years and the prevalence rate of constipation was 20.3%. The average SF-36 score was 63.5 in total population, 57.9 in constipation group, and 64.9 in normal group. CONCLUSION: These results suggest that the constipation lowers QOL in adults aged over 60 years old. Further study will be necessary to explore if QOL changes according to the severity of constipation and its treatment and to assess QOL using a disease-specific measurement tool that can be used for Korean environment.

Concern in and Utilization of the Mass Media Health Information in Community-dwelling Elderly / 가정의학회지

BACKGROUND: Recently, the mass media serves a major role in the public health education, but have not been proven whether they are being appropriately utilized in the elderly. The aim of this study was to identify the elderly person's concern in the mass media health information and utilization behavior. METHODS: Between March to June 2008, one to one survey with the elderly people over 60 years was performed in two elderly welfare centers, one public health center, and two secondary hospitals outpatients and inpatients in Seoul and Chungju. RESULTS: A total of 999 subjects were included. By multivariate analysis, factors significantly associated with low concern in the mass media health information were low educational level, non-exercise group, and low concern in own health (P = 0.001, 0.009, < 0.001, respectively). The most frequently utilized health information source was the mass media. By comparing the frequency of health information utilization, women, low educational level, low income, non-exercise group, underweight, low level of self-evaluated health status, and low concern in health information were significantly associated with the lowest quintile of utilization (P value: < 0.001, 0.005, 0.05, < 0.001, 0.002, 0.03, 0.005, respectively). However, the presence of chronic diseases, such as hypertension, diabetes, had no association. CONCLUSION: In community-dwelling elderly, important factors associated with concern in and utilization of the mass media health information were concern in health, self-evaluated health status, exercise status and socioeconomic factors such as education or income level, rather than comorbid chronic disease.

Biochemical Markers and Health Behavior Related with Bone Mineral Density in Adult Men / 가정의학회지

BACKGROUND: More than half of the causes of male osteoporosis is due to secondary osteoporosis. Therefore, it is important to detect and modify its related factors. The aim of this study was to find related lifestyle factors and biochemical markers with low bone mineral density (BMD) in Korean men. METHODS: A cross-sectional analysis was performed in men aged 40-69 years who visited a hospital for health checkup from January to March 2007. BMD was measured at proximal femur and lumbar spine by dual energy x-ray absorptionmetry. Lifestyle factors were estimated by a self-administered questionnaire and fasting glucose, uric acid, gamma glutamyltransferase, alkaline phosphatase, creatinine, free testosterone, 25-OH vitamin D, urine deoxypyridinoline, osteocalcin were measured. Multivariate logistic regression was used to find the association to the lowest tertile of BMD. RESULTS: A total of 152 subjects were included. After multivariate analysis adjusted with age, BMI, smoking, alcohol and exercise, different factors were correlated with low bone density in each site of femoral neck and lumbar spine. Factors correlated at both sites were BMI and exercise; lower BMI and doing no exercise increased risks of low bone density. Increasing age and alcohol intake > or = 14 drinks/week were associated with lower BMD at femoral neck. The factors associated with lower lumbar spine BMD only were lower level of uric acid and higher level of urine deoxypyridinoline. CONCLUSION: Different factors were associated with low bone density at femoral neck and lumbar spine in men. BMI and exercise were related in both sites; age, alcohol intake, uric acid and deoxypyridinoline were related on either site.

Effects of Whole Body Vibration Exercise on Body Weight and Body Composition in Young Adults / 가정의학회지

BACKGROUND: Whole body vibration exercise is currently being researched for potential therapeutic and exercise performance benefits. Little is known about the physiological effects of whole body vibration on humans. The aim of this study was to examine the effects of whole body vibration on body weight and body compositions. METHODS: One hundred and twelve healthy college students were separated into two groups; one was the whole body vibration exercise group, the other the control group. The exercise program was more than 10 minutes of whole body vibration exercise and the frequency was more than 3 times per week during three months. Body weight and body composition were checked at the beginning and the end point of this study. RESULTS: A total of 91 students finished this study (56 males, 35 females). No significant difference was found in body weight, body mass index, muscle mass, fat mass, body fat ratio, visceral fat area between the study and the control groups. In females, slight increase as found in body weight (exercise vs. control; 1.1 +/- 1.1 kg vs. 0.3 +/- 1.9 kg, P = 0.03), body mass index (0.5 +/- 0.4 kg/m2, 0.0 +/- 0.5 kg/m2, P = 0.002), fat mass (0.8 +/- 0.9 kg, -0.3 +/- 1.4 kg, P = 0.008), and fat ratio (1.0 +/- 1.5%, -0.6 +/- 2.4%, P = 0.03) in the study group compared with the control group, clinically significant or not. The increase mainly occurred in normal body mass index group in the female study group (P < 0.05). CONCLUSION: The results of this study suggest that whole body vibration exercise has no significant effect on reducing body weight and fat mass, visceral fat area and on increasing muscle mass.

Activation of Lysozyme and Lactoferrin in Endolymphatic Duct of Rats / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Secretory activity, particularly of antibacterial agents such as lysozyme and lactoferrin, is an important aspect of the mucosal defense mechanism. The development of these agents may have a direct bearing on the susceptibility of the mucosa to infection. The antibacterial secretory enzymes such as lysozymes and lactoferrins are found in various mucosal tissues, and it has been suggested that these enzymes contribut to the defense against local mucosal infection. Specifically, lysozyme and lactoferrin are important components of innate immunity against pathogens at mucosal surfaces. The purpose of this study is to identify the distribution and expression of lysozyme, lactoferrin in endolymphatic duct of rat. MATERIALS AND METHOD: Normal rats (129P3/J, 10 cases) were used for this study. The expression level and distribution of lysozyme mRNA were analyzed by RT-PCR and quantitative image analysis. RESULTS: The expression of lysozyme and lactoferrin mRNA in endolymphatic ducts of rats was compared by quantitative image analysis. The results indicate that the relative expression of lysozyme mRNA resulted as 2.5 times greater than that of lactoferrin mRNA. CONCLUSION: The distribution and expression of lysozyme and lactoferrin in the endolymphatic duct of rat were identified. The study suggests that innate immunity such as lysozyme and lactoferrin are important components of defense mechanisms along with mucociliary clearance. Additionally, the authors think that the activity of lysozymes is more effective than that of lactoferrin in the endolymphatic duct of rat.

The Relating Factor and Quality of Life of Overactive Bladder in Adults / 가정의학회지

BACKGROUND: Overactive bladder syndrome (OAB) is a common disorder in primary care that affects negatively on the quality of life of outpatients. However, little information is available on related factors and the quality of life in adults with overactive bladder. The purpose of this study was to find related factors of overactive bladder and to measure the quality of life in adults with overactive bladder. METHODS: Among the people who visited a hospital in Seoul and Chung-ju for a health examination or primary care between October 1 and December 31, 2008, we selected 327 participants over 20 years old. We measured their Overactive Bladder Questionnaire (OAB-q), took medical history and reviewed their demographic data. The relationship between OAB, other independent variables and health related quality of life (HRQL) were analyzed. RESULTS: Of 327 respondents, the prevalence of OAB in adults was 38 (11.6%). The factors related to OAB were age (P = 0.007), history of prescription for congestive heart failure (P = 0.023), benign prostatic hyperplasia (BPH) (P = 0.002), and depression (P = 0.008). OAB was significantly associated with BPH medication (P = 0.042; OR = 8.757) and depression medication (P = 0.005; OR = 9.977) in multivariable logistic regression analysis. In each T-test analysis, OAB decreased in HRQL. CONCLUSION: OAB is a common disorder in adults, history of BPH medication and depression medication is more common in OAB. The symptoms that were suggestive of OAB were affected negatively on the quality of life in adults. Effective health care polices and prompt management of OAB should be implemented.

Evaluation of Osteoporosis Self-Assessment Tool Usefulness as a Screening Test for Osteoporosis in Korean Men / 가정의학회지

BACKGROUND: This study was done to determine whether the Osteoporosis Self-assessment Tool (OST) can predict central bone mineral density in Korean men above 50 years, as defined by dual energy X-ray absorptionmetry (DXA). METHODS: We applied the OST index to Korean men aged over 50 in Health Promotion Center of Konkuk University Hospital from September 2005 to September 2008. The calculated OST risk index was based on weight and age, truncated to an integer. RESULTS: The study population was 276 men. The mean age, height and weight of the men were 59.7 +/- 6.69 years, 167.6 +/- 6.14 cm and 67.5 +/- 8.93 kg respectively. By DXA, 4.7% of the men had a T score of -2.5 or less, and 46.4% had a T score of -2 or less at the spine, total hip, or femoral neck. The OST index ranged from -4 to 7. Using a cutoff score of 0, we predicted osteoporosis with a sensitivity of 85% and a specificity of 62%. The receiver operating characteristic curve showed an area under the curve of 0.77. When the subjects were analyzed by age and smoking status, the predictive value of the OST was maintained. CONCLUSION: The OST is a simple and useful method to predict osteoporosis in Korean men.

Performance of the AUDIT Alcohol Consumption Questions (AUDIT-C) and AUDIT-K Question 3 Alone in Screening for Problem Drinking / 가정의학회지

BACKGROUND: In the busy primary care setting, there are several limitations in applying Alcohol Use Disorders Identification Test in Korea (AUDIT-K) to screen problem drinking. Thus, for primary healthcare practice, we evaluated AUDIT-C, which covers questions from 1 to 3 in AUDIT-K, and AUDIT-K Question 3 Alone to present cut points for these two screening questionnaire according to AUDIT-K test scores. METHODS: In a university hospital, we surveyed 302 males with a drinking history via self-administered questionnaire including AUDIT-K, from November 2007 to April 2008. On the basis of total score in AUDIT-K, we divided them into four groups: normal, problem drinking, alcohol use disorder, and alcohol dependence. For each alcohol drinking behavior pattern, we drew the receiver operating characteristics (ROC) curves to present cut points for appropriate sensitivity and specificity. In addition, we compared the performance of AUDIT-C and AUDIT-K Question 3 Alone through area under the curve (AUC). RESULTS: For AUDIT-C, we designated the score 8 or more as problem drinking, 9 or more as alcohol use disorder, and 11 or more as dependence. The results of sensitivity/specificity for each group were 82%/76%, 76%/79%, 80%/86%, respectively, which were suitable for screening. For AUDIT-K Question 3 Alone, we defined the score 3 or more as problem drinking or alcohol use disorder and the score 4 as dependence. The results of sensitivity/specificity for each group were 79%/80%, 84%/67%, 85%/77%, which were appropriate for screening. For every drinking behavior group, AUDIT-C was superior to AUDIT-K Question 3 Alone in screening performance (problem drinking: 0.88 vs. respectively 0.85, alcohol use disorder: 0.86 vs. 0.82, alcohol dependence: 0.88 vs. 0.81) CONCLUSION: We confirmed that both AUDIT-C and AUDIT-K Question 3 Alone, which are more convenient and have fewer time con-straints than AUDIT-K, are reasonable screening methods for problem drinking. Thus, we recommend further drinking assessment and proper intervention for male drinkers who have scores 8 or more in AUDIT-C or 3 or more in AUDIT-K Question 3 Alone.

Relations between the Dietary Habits and Components of the Metabolic Syndrome in Premenopausal Women

BACKGROUND: In these days the metabolic syndrome threatens many people of Korea. Several studies have suggested that the dietary habits are associated with the risk of the metabolic syndrome. The purpose of this study was to find out relations between the components of the metabolic syndrome and the dietary habits. METHODS: The subjects of this study included 1,005 non-smoking premenopausal females aged from 20 to 49 years old who visited the health promotion center of a university hospital. Dietary questionnaire was composed of dietary habits and specific food intake frequency during the past 3 months. RESULTS: The subjects who had more than one metabolic components were 361 (36%), and those who had the metabolic syndrome was 35 (3.5%). After multivariate logistic analysis adjusted with age, BMI, smoking status, alcohol intake, and exercise, the abdominal obesity risk was significantly increased in those who had irregular meals (P for trend= 0.049), skip meals (P for trend=0.050), faster meal time (P=0.017), and intake of saturated fat more frequently (P=0.043). The abdominal obesity risk was significantly increased in those who overate or binged eating 7gt; or =3 times/week than <1 time/week {OR (95% CI), 2.49 (1.07~5.80)}, intake fruit <1 time/week than 6~7 times/week {OR (95% CI), 4.46 (1.20~16.54)}. A risk for high blood pressure was significantly increased in those who had breakfast 1~2 times/week than those had it 6~7 times/week {OR (95% CI), 1.91 (1.07~3.42)}. The risk for impaired fasting glucose was significantly increased in those had breakfast <1 time/week than those who had 6~7 times/week {OR (95% CI), 2.27 (1.20~4.28), P for trend=0.018}. CONCLUSION: There was a correlation between dietary habits and metabolic syndrome components. Among the dietary habits, irregular meals, skipping breakfast, skipping meals, fast meal time, overeating or binge eating tendency, low intake of fruits and high intake of saturated fat were associated with the risk of the metabolic syndrome components.

Family Physicians' Perception on Hearing Impaired People

BACKGROUND: Hearing impaired people have a lot of difficulty in communicating when they visit medical institutions. This study was to reveal the family physicians' perception and attitude for the hearing impaired people, and the effect of those factors on the actual physicians' practice behavior for the disabled. METHODS: We sent questionnaires by post mail to 1,000 members listed in the 2007 address book of the Korean Association of Family Medicine. RESULTS: Among the total of 90 family physicians who had answered, 72 (80.8%) had willing attitude to treat the hearing impaired people, and the most important reason was that it was essentially a doctor's duty. In the group who were unwilling to treat the disabled, the most principal reason was that they were not equipped with sufficient facility and medical system. Gender was the only factor affecting the physicians' attitude significantly and the female doctors had a higher intention to treat the hearing impaired people than male doctors (P=0.035). Age, location of hospital, number of patients, practical experience of hearing impaired people had no significant effect on doctors' attitude. The number of physicians who volunteered to participate for the hearing impaired people's health promotion personally was significantly higher in the group of treatment intention (P=0.007). Nevertheless, few physicians had the willingness to equip the hospital facility for the hearing disabled, even in the group of willingness to treat the disabled. The most important reason was that very few disabled patients visit their clinic, and so forth they felt no necessity to improve and re-organize their clinical environment. CONCLUSION: Most family physicians are willing to treat hearing impaired people. But even in the willing group, almost all of them are unwilling to improve or equip the medical facilities for the hearing impaired people personally, because only a few disabled people visit the primary care hospital in the real practice.

The Usefulness of Heavy Smoking Index as a Test for Nicotine Dependence

BACKGROUND: The Fagerstrom Test for Nicotine Dependence (FTND) is a widely used six-item questionnaire. Its completion require a few minutes, but such time may be too much for busy clinicians and large epidemiologic surveys. The goals of this study was to compare the sensitivity and the specificity of Heavy Smoking Index (HSI) of high nicotine dependence. METHODS: The FTND was administered to 943 current smokers from a smoking-cessation clinic in Gwangjin-gu, Seoul. The HSI which combines two items of the FTND (the number of cigarettes per day and the time of the first cigarette of the day) was compared to the FTND. We measured cigarette per day, duration of smoking, and age of smoking initiation. RESULTS: A cutoff score equal or greater than 4 on the HSI detected a similar rate of nicotine dependence as a cutoff score equal or greater than 6 on the FTND. The HSI showed a sensitivity of 88.0% and a specificity of 86.5%. The concordance between the two instruments was high (kappa= 0.74). CONCLUSION: The HSI was proven to be very useful. If HSI had a proper validity, the HSI can be a good standard of high nicotine dependence for busy clinician and epidemiologists.

The Validity of Michigan Neuropathy Screening Instrument as a Screening Test and Risk Factors for Diabetic Peripheral Neuropathy

BACKGROUND: Diabetic neuropathy is a common complication of diabetes. Since neuropathy leads to ulceration and amputation, efforts to detect early and to elucidate its risk factors are ongoing. The goal of this study was to check the validity of Michigan neuropathy screening instrument (MNSI) as a screening test and its risk factors for diabetic neuropathy. METHODS: A total of 75 subjects with type II diabetes mellitus, who visited a university hospital, were investigated. We measured their duration of diabetes, height, weight, systolic blood pressure, diastolic blood pressure, fasting glucose, glycosylated hemoglobin, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total cholesterol, serum creatinine, and 24-h urine albumin. MNSI tested and electrophysiological test were performed. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of MNSI was 63.5%, 78.3%, 86.8%, and 48.6%, respectively. Statistically significant relationships were found between neuropathy and the duration of diabetes and total cholesterol. CONCLUSION: MNSI seemed to be an appropriate screening test for diabetic neuropathy. More attention must be paid to the duration of diabetes and the total cholesterol of type 2 diabetic patients with peripheral neuropathy.

Prevalence of Renal Diseases and Its Related Risk Factors in Patients Undergoing Comprehensive Medical Examination in a University-based Hospital

BACKGROUND: Renal function in patients, who undergo medical examination, is usually evaluated by the serum creatinine level. However this numerical value does not always represent the entire renal function because the values increases only when the renal function has decreased more than 50%. The purpose of this study was to find the prevalence of renal diseases through the GFR (Glomerular filtration rate) using MDRD (Modification of Diet in Renal Disease) equation and to analyze the risk factors related to renal diseases. METHODS: We reviewed all the clinical records of 440 patients who had visited for medical examination between January 1, 2004 and December 31, 2004. We have calculated the GFR for each group using the MDRD equation and then figured out the correlation between the GFR and its risk factors. RESULTS: Patients haing GFR of less than 60 mL/min/1.73 m2 were 19 (7.2%), 60~90 mL/min/1.73 m2 were 123 (46.4%) and more than 90 mL/min/1.73 m2 were 123 (46.2%). The correlation between the GFR and age, obesity, hypertension and diabetes melitus were observed as negative results in univariate analysis of variance (P<0.05). Age and diabetes melitus were independent factors affecting the GFR (OR=3.1, 2.2 respectively, P<0.05) in multiple logistic regression analysis. CONCLUSION: It is a well known fact that the declined renal function is related to the aging process and diabetes melitus. Therefore, the mortality rate caused by renal failure and its complications should be decreased through the control of diabetes melitus, aging process and other risk factors.

Erratum: Efficient gene delivery in differentiated human embryonic stem cells. Exp Mol Med 2005;37:36-44

The authors would like to amend a reference (Lee et al., 2003) that was cited in "Cell culture" section of "Materials and Methods". Instead of "(Lee et al., 2003)", we would like to change the reference to "(Kim et al., 2003)". In "References", it also needs to include the following reference. Kim YY, Seol HW, Ahn HJ. Temporal expression of differentiation markers in embryoid bodies from various human embryonic stem cell line. International Society for Stem Cell Research 1st Annual Meeting, Washington, DC. U.S.A. June 8-11, 2003, Abstract No. 35. The authors apologize for any inconvenience.

Factors Influencing the Impulse of Suicide in Adolescence

BACKGROUND: Suicide is one of the ten largest causes of death in the world. The rate of suicide is recently significantly increasing in Korea and the rate is relatively high, particularly in adolescence. The purpose of this study was to support the establishment of appropriate measures for prevention of suicide through a better recognition of suicide and to investigate the factors that lead to suicide in adolescence with high school students who have large risk factors of suicide due to entrance examination, future courses, etc. METHODS: A questionnaire regarding the factors influencing the impulse of suicide was conducted to 770 high school students in eight high schools in Seoul and local areas between June 1 and July 31, 2005. Suicidal impulses was checked by SSI (scale for suicidal ideation). Depressive mood and internet addiction degrees was evaluated by BDI (Beck's depression inventory) and IAS (internet addiction scale), respectively. RESULTS: The final subjects of the study were 719 (93.3%) high school students among 770 students in eight high schools in Seoul and local areas, excluding 51 (6.6%) students with insufficient response. There were, 362 (50.3%) male students and 357 (49.7%) female students. Among the total 443 (61.6%) of the subjects had a high risk of suicide. The risk was high in subjects whose parents were divorced, who solved their difficulties by themselves, either expressed suicidal ideation to friends or not expressed suicidal ideation, knew an suicidal internet site and had freguent visits to the internet site. And alcohol experience, drug abuse, BDI and IAS were also connected with a high risk of suicide (P<0.05). Marital status of parents, resolution of problems, expression of suicidal ideation, BDI and IAS were independent factors affecting SSI (OR= 3.7, 0.7, 0.8, 2.4, and 1.6, P<0.05) in logistic regression analysis. CONCLUSION: High suicidal risk is associated with complex factors. We have discovered several causes which augment the impulse of suicide in adolescence. They are parent's divorce or separation, an expression of suicidal ideation, depressive mood, and the extent of internet addiction, etc. Therefore in order, to prevent adolescent suicide, a unified personal, family, and social efforts are required.

Identification of a putative transactivation domain in human Nanog

Nanog is a newly identified divergent homeodomain protein that directs the infinite propagation and sustains the pluripotency of embryonic stem cells. It has been reported that murine Nanog has two potent transactivation domains in N-terminal and C-terminal regions. Human Nanog (hNanog) polypeptide shares about 58% and 87% identity to the open reading frame and homeodomain of murine Nanog, respectively. However, the functional domains and molecular mechanisms of hNanog are poorly understood. In this study, for the first time, we presented that only C-terminus of hNanog contains a potent transactivation domain. Based on the amino acid sequences of homeobox domain, we roughly divided hNanog open reading frame into the three regions such as N-terminal, homeodomain and C-terminal regions and constructed either the fusion proteins between hNanog individual and Gal4 DNA binding domain or the context of native hNanog protein. Reporter assays by using reporter plamid containing Gal4 or Nanog binding site revealed that the only C-terminal region exhibited the significant fold induction of transactivation. However, interestingly, there was no significant activation through N-terminal region unlike murine Nanog, suggesting that C-terminal region may have more critical roles in the transcriptional activation of target genes. Taken together, the finding of a putative transactivation domain in hNanog may contribute to the further understanding of molecular mechanism on the regulation of downstream genes involved in self-renewal and pluripotency of human stem cells.

Overexpression of SOX9 in mouse embryonic stem cells directs the immediate chondrogenic commitment

Mouse embryonic stem (mES) cells are capable of undergoing chondrogenesis in vitro. To enhance this process, the human SOX9 (hSOX9) cDNA was delivered into mES cells and the clones overexpressing hSOX9 (denoted as mES-hSOX9 cells) were verified by Western blot analysis. The transcripts of collagen IIA (a juvenile form), aggrecan and Pax1 were expressed in mES-hSOX9 cells grown on feeder layers, suggesting the immediate effect of exogenous SOX9 on chondrogenesis. However, SOX9 overexpression did not affect the cell cycle distribution in undifferentiated mES cells. Upon differentiation, collagen IIB (an adult form) was detected in day 3 immature embryoid bodies. In addition, the overexpression of exogenous SOX9 significantly induced transcriptional activity driven by SOX9 binding site. Taken together, we for the first time demonstrated that constitutive overexpression of exogenous SOX9 in undifferentiated mES cells might have dual potentials to induce both chondrogenic commitment and growth capacity in the undifferentiated status.