PURPOSE: The healthy worker effect is an important issue in occupational epidemiology. This study was conducted to propose a new method to test the relation between exposure and mortality in the presence of the healthy worker effect. METHODS: In this study, the healthy worker hire effect was assumed to operate as a confounding variable of health status at the beginning of employment and healthy worker survival effect as a confounding and intermediate variable of employment status. In addition, the proposed method reflects the length bias sampling caused by changing of an employment status. Simulation studies were also carried out to compare the proposed method with Cox's time dependent covariates models . RESULTS: The theoretical development of the healthy worker survival effect is based on the result that an observation with change of an employment status requires that the survival time without intermediate event exceeds the waiting time for the intermediate event. According to our simulation studies, both the proposed method and Cox's time dependent covariates model which includes the change of employment status as time dependent covariates seem to be satisfactory at 5% significance level. However, Cox's time dependent covariates models without or with the change of employment status as time fixed covariate are unsatisfactory. The proposed test is superior in power to tests based on Cox's model. CONCLUSIONS: The healthy worker effect may not be controlled by classical Cox's proportional hazards models. The proposed method performed well in the presence of healthy worker effect in terms of level and power
Bias (Epidemiology) ; Confounding Factors (Epidemiology) ; Employment ; Epidemiology ; Healthy Worker Effect* ; Mortality ; Proportional Hazards Models

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare disease characterized by fever, hepatosplenomegaly, cytopenia and non-malignant lymphohistiocytic infiltration with hemophagocytosis in reticulendothelial organs. We experienced three cases of FHL in identical male twins and their younger brother who presented with fever and severe hepatosplenomegaly. Cytopenia, elevated serum transaminase and low serum albumin levels, hypertriglyceridemia were common laboratory findings of them. One of them showed markedly decreased phytohemagglutinin induced lymphocyte proliferation and reversed CD4/CD8 ratio (0.52) in flowcytometric lymphocyte subset analysis. Aspirate of bone marrow revealed typical features consistent with FHL in two of them. In spite of recent therapeutic approaches, none of them survived.
Bone Marrow ; Fever ; Humans ; Hypertriglyceridemia ; Lymphocyte Subsets ; Lymphocytes ; Lymphohistiocytosis, Hemophagocytic* ; Male ; Rare Diseases ; Serum Albumin ; Siblings

Myotonic dystrophy is a multisystemic disorder inherited as an autosomal dominant trait. The characteristic clinical features include the presence of myotonia, atrophy of the muscles of the face and the sternocleidomastoids and numerous nonmusclar manifestations such as cataracts, frontal baldness, gonadal dysfunctions and cardiac abnormalities. We experienced one case of myotonic dystrophy with prolonged atrial flutter in 30-year-old male who was admitted because of palpitation. We present this case with reviewing literatures.
Adult ; Alopecia ; Atrial Flutter* ; Atrophy ; Cataract ; Gonads ; Humans ; Male ; Muscles ; Myotonia ; Myotonic Dystrophy*

No abstract available.
Abruptio Placentae* ; Female ; Pregnancy

No abstract available.
Abruptio Placentae* ; Female ; Pregnancy

Obesity is one of the well-known risk factors of breast cancer. We evaluated the relationship between serum adiponectin and resistin levels and breast cancer risk in 41 biopsy-proven breast cancer patients and 43 age- and body mass index-matched controls. The mean serum adiponectin level was lower in the breast cancer group than the control group (6.93+/-3.2 microgram/mL, vs. 7.60+/-3.5 microgram/mL), but this difference did not reach statistical significance (p=0.37). There was a statistically significant difference in serum resistin levels between the groups (breast cancer group 5.23+/-6.9 ng/mL vs. control 1.46+/-2.0 ng/mL; p<0.001). The risk of breast cancer was significantly increased in the highest tertile group for serum resistin level compared to the lowest tertile group (adjusted odds ratio 2.77 [95% CI 1.40-5.50]). The lymph node metastasis was significantly increased in the patients with less than the median adiponectin level (p=0.017). In the patients whose resistin level was higher than the median, the frequency of tumor with the highest histological grade was significantly increased (p=0.025). In conclusions, both the low serum adiponectin levels and high resistin levels are likely to be associated with increased breast cancer risk in Korean women.
Resistin/*blood ; Odds Ratio ; Middle Aged ; Insulin Resistance ; Humans ; Female ; Case-Control Studies ; Breast Neoplasms/*blood/etiology/pathology ; Adult ; Adiponectin/*blood

We report a case of coincidental pituitary adenoma and sphenoid meningioma. Computed tomographic scan had shown a large intrasellar rim enhancing mass and another well-enhancing mass with reactive bony thickening on the medial sphenoidal ridge. Magnetic resonance image revealed a snow-man shaped, expansile intrasellar mass, with small supra-sellar component, and a small enplaque-type enhancing dural thickening on the right medial sphenoidal ridge. Histopathologically, the intrasellar mass was diagnosed as pituitary adenoma and the other mass as secretory meningioma. We present clinical, radiological, and histopathological findings and review the reported cases of coincidental pituitary adenoma and meningioma without irradiation or trauma.
Brain Neoplasms ; Meningioma* ; Pituitary Neoplasms* ; Sphenoid Bone

Even though malignant potential of vaginal intraepithelial neoplasia(VaIN) may be low, the prevalence is increasing and the mean age at diagnosis is decreasing. Various treatment options have been used for the eradication of ValN, but most effective standard protocol is not present because it is a rare disease. Laser vaporization was used to treat 7 patients with VaIN diagnosed at Department of Obstetrics and Gynecology, Seoul National University Hospital between 1992 to 1996. The patients were from 40 to 70 years of age with a mean 57 of years. All patients had a history of radical or simple hysterectomy, and final pathologic diagnosis were as follows : cervical cancer(n=5), cervical intraepithelial neoplasia(n=l), leiomyoma(n=l). Vaginal intrae-pithelial neoplasia(VaIN) was identified between 4 months and 8 years after first operation. All lesions were unifocal disease and found at the upper one third of the vagina. Treatment was performed with a CO2 laser unit and colposcope. Four(57%) out of seven patients had general anesthesia for the purpose of treatment. Patients were followed up for an average of 16.8 months with regular cytologic evaluation, colposcopy and biopsy. Failure of therapy was defined as evidence of intraepithelial neoplasia in any one of these three parameters. Only one patients showed persistent disease and the others remain free of disease. The success rate of therapy was 85.7%(6/7). (continue)
Anesthesia, General ; Biopsy ; Colposcopes ; Colposcopy ; Diagnosis ; Gynecology ; Humans ; Hysterectomy ; Laser Therapy ; Lasers, Gas* ; Obstetrics ; Prevalence ; Rare Diseases ; Seoul ; Vagina ; Volatilization*

PURPOSE: This study was performed to assess the clinical and epidemiological changes after the introduction of the rotavirus vaccine in Korea, as well as to determine the efficacy of the rotavirus vaccine among hospitalized rotaviral gastroenteritis patients over the past two years. METHODS: We analyzed yearly and seasonal patterns of 1,165 inpatients who were hospitalized for rotaviral gastroenteritis under the age of 5 years between 2006 and 2013. We also conducted a survey among 460 gastroenteritis patients who were hospitalized between 2012 and 2013 regarding the rotavirus vaccination and the symptoms of gastroenteritis. Among those individuals surveyed, clinical indices were analyzed for 124 patients who were tested positive for the rotavirus antigen. RESULTS: The incidence of Rotaviral gastroenteritis have decreased significantly by year 2010. After the introduction and widespread dissemination of the rotavirus vaccine, the onset of the disease and the seasonal peak have been delayed. Overall, the vaccinated group showed a lower rate of positivity than the unvaccinated group. Among the hospitalized rotaviral gastroenteritis patients, the vaccinated group had a shorter hospitalization period, less severe clinical symptoms of gastroenteritis, and better laboratory test results. CONCLUSIONS: After introduction of the rotavirus vaccine in Korea, there were two main trends observed: 1) the overall level of disease incidence was reduced; 2) the severity of rotaviral gastroenteritis cases also decreased. Based on this data, more children should receive vaccination in order to prevent the rotavirus infection and decrease the severity of rotaviral gastroenteritis.
Child ; Epidemiologic Studies* ; Epidemiology ; Gastroenteritis* ; Hospitalization ; Humans ; Incidence ; Inpatients ; Korea ; Rotavirus Infections ; Rotavirus* ; Seasons ; Vaccination