OBJECTIVES: In large-scale field trials, randomization by cluster is frequently used because of the administrative convenience, a desire to reduce the effect of treatment contamination, and the need to avoid ethical issues that might otherwise arise. Cluster randomization trials are experiments in which intact social unit, e.g., families, schools, cities, rather than independent individuals are randomly allocated to intervention groups. The positive correlation among responses of subjects from the same cluster is in matter in cluster randomization. This thesis is to compare the results of three randomization methods by standard error of estimator of treatment effect. METHODS: We simulated cholesterol data varing the size of the cluster and the level of the correlation in clusters and analyzed the effect of cholesterol-lowering agent. RESULTS: In intra-cluster randomization the standard error of the estimator of treatment effect is smallest relative to that in inter-cluster randomization and that in individual randomization. CONCLUSIONS: Intra-cluster randomization is the most efficient in its standard error of estimator of treatment effect but other factor should be considered when selecting a specific randomization method.
Cholesterol ; Ethics ; Humans ; Random Allocation*

The objective of the study was to observe the effect of n-3 PUFA on cell proliferation and apoptosis by determining mRNA and protein of COX-2 and eicosanoid product and the mRNA and protein of Bu and Bcl-2 related to apoptosis in colon carcinogenesis of 1,2- dimethylhydrazine (DMH)-treated rats. Ninety male Sprague Dawley rats weighing about 170g were divided into 3 groups, control and n-3 PUFA supplemented groups (FO group: 6.2 mmoles n-3 PUFA; 2FO group: 12.4 mmoles n-3 PUFA) and fed experimental diet for 14 weeks. All rats were intramuscularly injected with DMH 15 mg/kg twice a week for 6 weeks to deliver total dose of 180 mg/kg body weight. Compared with the control group, 6.2 mmoles n-3 PUFA significantly reduced the levels of mRNA and protein expression of COX-2 and 2-series eicosanoids (TXB2 and PGE2 and decreased cell proliferation in colonic mucosa. However, high levels of n-3 PUFA supplementation significantly increased the levels of mRNA and protein expression of COX-2, TXB2 and PGE2. and increased cell proliferation which was similar level to that of control group. Compared with the control group, n-3 PUFA, regardless of the amount, significantly increased apoptotic index in colonic mucosa. Western blot and RT-PCR analyses showed that the levels of mRNA and protein expression of Bax were significantly increased by 6.2 mmoles n-3 PUFA, but decreased by 12.4 mmoles n-3 PUFA. The analyses also showed the levels of mRNA and protein expression of Bcl-2 were significantly reduced by 6.2 mmoles n-3 PUFA, but increased by 12.4 mmoles n-3 PUFA. The ratio of Bcl-2/Bax in mRNA and protein was significantly reduced by 6.2 mmoles n-3 PUFA but increased by 12.4 mmoles n-3 PUFA. Overall, these results indicate that n-3 PUFA could be effective in preventing colon carcinogenesis by reducing cell proliferation with lower level of COX-2 and 2-series eicosanoid, and increasing apoptosis by inducing pro-apoptotic gene, Bax and inhibiting anti-apoptotic gene, Bcl-2 in the colonic mucosa of DMH-treated rats. However, high level of n-3 PUFA supplementation could stimulate colon carcinogenesis by increasing cell proliferation and inhibiting apoptosis.
Animals ; Apoptosis ; Blotting, Western ; Body Weight ; Carcinogenesis* ; Cell Proliferation ; Colon* ; Control Groups ; Diet ; Dimenhydrinate ; Dinoprostone ; Eicosanoids ; Fatty Acids, Omega-3* ; Genes, bcl-2 ; Humans ; Male ; Mucous Membrane ; Rats* ; Rats, Sprague-Dawley ; RNA, Messenger

BACKGROUND: Even though several oral anti-diabetic drugs (OAD) with various modes of action are replacing sulfonylurea (SU), some patients seem to be dependent on SU for adequate glycemic control. Therefore, we evaluated the clinical characteristics of such patients. METHODS: We selected the patients with type 2 diabetes who met following criteria from 2009 to 2014 at Seoul National University Hospital: glycated hemoglobin (HbA1c) was maintained below 7.5% for at least 6 months under small dose of SU (glimepiride < or =2 mg/day or equivalent dose); after discontinuation of SU, HbA1c increased > or =1.2% within 3 months or > or =1.5% within 6 months; and after resuming SU, HbA1c reduction was > or =0.8% or reduction of fasting plasma glucose was > or =40 mg/dL within 3 months. Patients with impaired hepatic or renal function, and steroid users were excluded. RESULTS: Nineteen subjects were enrolled: after averaged 4.8+/-1.5 months of SU-free period, HbA1c increased from 6.7%+/-0.4% to 8.8%+/-0.8% even though adding other OAD such as gliptins. However, HbA1c decreased to 7.4%+/-0.7% after resuming SU within 2.4+/-0.8 months. There was no sexual predominance. Despite their old age (67+/-11 years) and long duration of diabetes (18+/-10 years), fasting C-peptide was relatively well-reserved (3.9+/-2.6 ng/mL), and nephropathy was not observed (albumin-creatinine ratio 21.2+/-16.6 mg/g and estimated glomerular filtration rate 75.8+/-18.0 mL/min/1.73 m2). Strong family history was also noted (73.7%). CONCLUSION: Despite hypoglycemia risk of SU, it seemed indispensable for a subset of patients with regard to insulin secretion. Genetic influences would be evaluated.
Blood Glucose ; C-Peptide ; Diabetes Mellitus ; Dipeptidyl-Peptidase IV Inhibitors ; Fasting ; Glomerular Filtration Rate ; Hemoglobin A, Glycosylated ; Humans ; Hypoglycemia ; Insulin ; Seoul

Varicella is usually considered to be a benign disease in healthy children; however, serious complications can occur such as necrotizing fasciitis and toxic shock syndrome. We describe a 38-month-old girl with necrotizing fasciitis and streptococcal toxic shock syndrome following varicella. She was previously healthy and vaccinated against varicella at 12 months of age. She had been diagnosed with varicella three days prior to presenting at our facility; she developed fever, vomiting, and painful swelling on her left flank. Her skin lesions worsened, she became lethargic, and had episodes of hypotension and coagulopathy. Necrotizing fasciitis on the left abdominal wall, buttocks, and left thigh was diagnosed by magnetic resonance imaging, and group A Streptococcus was isolated from a tissue culture. She was diagnosed as necrotizing fasciitis and streptococcal toxic shock syndrome, and successfully treated with repeated surgical debridement and fasciotomy, in addition to intensive antibiotics. Our experience suggests that necrotizing fasciitis in patients with varicella should be considered to be a rare complication even with widespread vaccine use. Early diagnosis and intensive treatment are required to prevent a fatal outcome.
Abdominal Wall ; Anti-Bacterial Agents ; Buttocks ; Chickenpox* ; Child* ; Child, Preschool ; Debridement ; Early Diagnosis ; Fasciitis, Necrotizing* ; Fatal Outcome ; Female ; Fever ; Humans ; Hypotension ; Magnetic Resonance Imaging ; Shock, Septic* ; Skin ; Streptococcus ; Streptococcus pyogenes ; Thigh ; Vomiting

PURPOSE: Eosinophilia may be associated with various primary and reactive conditions. However, studies on the cause and incidence of eosinophilia in Korean children are rare. This study aimed to evaluate the cause and incidence of eosinophilia in patients at a single university hospital. METHODS: We studied 8,285 pediatric patients under the age of 18 years who had eosinophilia at Pusan National University Hospital. Premature and newborn infants were excluded. Eosinophilia was defined as an absolute eosinophil count greater than 450/microL. Eosinophilia was categorized as mild (450-1,500/microL), moderate (1,500-5,000/microL), and severe (>5,000/microL). The underlying conditions of eosinophilia were retrospectively investigated. RESULTS: Of 8,285 patients who had a hematology profile, 497 (5.9%) were found to have eosinophilia. Of patients with eosinophilia, 333 patients (67.0%) had identifiable and possible causes. The major causes of eosinophilia were allergic diseases (61.3%), infectious diseases (19.8%), immunologic diseases (9.0%) and hemato-oncologic disease (5.1%). Immunological disease such as Idiopathic hypereosinophilic syndrome, drug induced hypersensitivity syndrome and Graft-versus-host disease was the common condition with moderate to severe eosinophilia in which eosinophil count in peripheral blood was more than 1,500/microL. CONCLUSION: The most common cause of eosinophilia was allergic disease. Immunological disease was the common condition with moderate to severe eosinophilia.
Busan ; Child* ; Communicable Diseases ; Eosinophilia* ; Eosinophils ; Graft vs Host Disease ; Hematology ; Humans ; Hypereosinophilic Syndrome ; Hypersensitivity ; Immune System Diseases ; Incidence* ; Infant, Newborn ; Retrospective Studies

Purpose: The aim of this study was to examine whether gonadotropin-releasing hormone (GnRH) agonist treatment is effective in preserving final height in patients with central precocious puberty (CPP) or early puberty (EP). Methods: The medical records of 40 patients with CPP and 206 patients with EP who completed GnRH agonist treatment following diagnosis were analyzed retrospectively. Height and height standard deviation (height SDS) scores based on bone age (BA) were measured and calculated at baseline, after treatment completion, and at final follow-up to compare changes within and between groups. Predicted adult height (PAH) was estimated by the height corresponding to height SDS for BA in girls at 18 years 11 months of age based on the growth chart. Results: PAH at baseline did not differ significantly between the CPP group (153.67±4.95) and the EP group (154.77±3.72). In the CPP group, PAH significantly increased at treatment completion (156.01±4.61) and at final follow-up (158.52±6.04) compared to baseline. In the EP group, PAH significantly increased at treatment completion (157.7±3.60) and at final follow-up (159.31±4.26) compared to baseline. The increase in PAH at all timepoints compared to baseline did not significantly differ between the CPP and EP groups. Conclusion Both CPP and EP groups had significantly greater PAH after treatment, with no difference in the amount of increase between groups. These results show that GnRH agonist treatment can help increase final height even in patients diagnosed with EP after the age of 8 years.

The mental health of medical students deserves attention because the problems in students may negatively influence learning ability and create consequences for later adjustment to doctor's role. The purpose of this study is to understand the stress, copying, self-esteem and subjective general well-being of medical students and compare them with other students group (students of law, science and humanities). The results was as follows : First, medical students did not report more stress but they use less copying strategy than other students group. Second, there was no differences in stress, copying, self-esteem and general well-being between high and low academic achievement group in medical students. Futhermore, study-related stress had more close relationship with self-esteem, general well-being. Third, the preparatory course students showed lower score in general well-being, especially health, cheerful-depressive mood domain. These results imply that mental health promotion programmes focused in guiding adjustment for the preparatory course students are helpful. And psychiatric, academic counseling should be made available to them. It can lead to an improvement in our health care delivery system. The need of additional longitudinal research is discussed.
Counseling ; Delivery of Health Care ; Humans ; Jurisprudence ; Learning ; Mental Health ; Students, Medical*

OBJECTIVES: Controversial arguments exists on both the case for and against on the accumulation of mitochondrial DNA (mtDNA) deletion in association to tissue and age. The debate continues as to whether this mutation is a major contributor to the phenotypic expression of aging and common degenerative diseases or simply a clinical insignificant epiphenomenon. The objective of this study was to determine whether the accumulation of mtDNA deletion is correlated with age-related and tissue-specific variation. MATERIALS AND METHODS: One hundred and fifty-seven tissues from blood, ovary, uterine muscle, and abdominal muscle were obtained from patients ranging in age from 31~60 years. After reviewing the clinical reports, patients with mitochondrial disorder were excluded from this study. The tissues were obtained at gynecological surgeries with the consent of the patient. Total DNA isolated from blood, ovary, uterine muscle, and abdominal muscle was amplified by two rounds of PCR using two pairs of primers corresponding to positions 8225-8247 (sense), 13551-13574 (antisense) for the area around deleted mtDNA and 8421-8440 (sense), 13520-13501 (antisense) for nested PCR product. A statistical analysis was performed by c2-test. RESULTS: About 0% of blood, 94.8% of ovary, 71.4% of uterine muscle, and 86.1% abdominal muscle harbored mtDNA deletion. When we examined the proportion of deleted mtDNA according to age deletion rate was 90% of ovary, 63.6% of uterine muscle, 77.7% of abdominal muscle in thirties and 100% of all tissue in fifties. CONCLUSION: The findings of this study suggest that the mtDNA deletion is varied in tissue-specific pattern and increases with aging.
Abdominal Muscles ; Aging ; Animals ; DNA ; DNA, Mitochondrial* ; Female ; Gynecologic Surgical Procedures ; Humans ; Mice ; Mitochondrial Diseases ; Myometrium ; Ovary ; Polymerase Chain Reaction

BACKGROUND: Hypertrophic scar following a burn is caused by the excessive deposit of collagen resulting in an exaggerated wound healing response. The burn patient complains of pain and itching over the scar, which can give rise to cosmetic and functional problems. OBJECTIVE: The aim of this study was to investigate the clinical and histological correlation of a hypertrophic burn scar for itching and pain sensations. METHODS: Thirty-eight patients underwent a scar release and skin graft. the modified Vancouver scar scale and the verbal numerical rating scale were recorded. All biopsies were taken from scar tissue (scar) and normal tissue (normal). Histologically, tissues were observed in the epidermis, the monocytes around the vessels, the collagen fiber, elastic fiber, and the mast cells. RESULTS: The mean total score of MVSS was 8.4+/-2.7 (pliability 2.0+/-0.9; thickness 1.8+/-0.9; vascularity 2.0+/- 0.9; and pigmentation 2.1+/-0.9). Pain and itching were 2.4+/-2.0 and 2.9+/-3.0. Epidermis were 7.9+/-2.8 layers (scar) and 4.0+/-0.8 layers (normal). The collagen fibers were thin and dense (scar) and thicker and loose (normal). The elastic fibers were thin and nonexistent (scar) and thin and loose (normal). Mast cells were 11.2+/-5.8/high power field (scar) and 7.4+/-4.1 (normal). CONCLUSION: As the scar tissue thickens, the itching becomes more severe. The stiffness of the scar with the pain appeared to be associated with the condition of the tissue. The correlation between clinical and histological post-burn hypertrophic scars will help further studies on the scar. This helped with the development of the base material for therapeutic strategies.
Biopsy ; Burns ; Cicatrix ; Cicatrix, Hypertrophic* ; Collagen ; Elastic Tissue ; Epidermis ; Humans ; Mast Cells ; Monocytes ; Pigmentation ; Pruritus* ; Sensation* ; Skin ; Transplants ; Wound Healing

OBJECTIVES: This study was conducted in order to develop the Korean version of the Reasons for Living Inventory for Adolescents (KRFL-A) and to investigate the reliability and validity of the KRFL-A. METHODS: The KRFL-A, Scale for Suicidal Ideation (SSI), Beck Hopelessness Scale (BHS) and Adolescent Suicide Questionnaire (ASQ) were administered to 720 first grade high school students. We examined the test-retest reliability, internal consistency of KRFL-A, and performed factor analysis. We also evaluated the correlation between KRFL-A and other scales, and the discrimination validity of KRFL-A between suicide attempt and non-attempt groups. RESULTS: Test-retest reliability, item-total correlation and internal consistency were all reliable. From factor analysis, three factors were extracted. The KRFL-A showed negative correlation with SSI and BHS scales. In addition, it could discriminate the suicide attempter group from the non-attempter group. CONCLUSION: The Korean version of the Reasons for Living Inventory was found to be reliable and valid for use in assessing the risk of suicide in adolescents.
Adolescent* ; Discrimination (Psychology) ; Humans ; Reproducibility of Results* ; Suicidal Ideation ; Suicide ; Weights and Measures ; Surveys and Questionnaires