Young-Wook Kim

Assessment of exposure to heavy metals and health risks among residents near abandoned metal mines in Goseong, Korea.

Metal contamination from mining activity is of great concern because of potential health risks to the local inhabitants. In the present study, we investigated the levels of Cd, Cu, As, Pb, and Zn in environmental samples and foodstuffs grown in the vicinity of the mines in Goseong, Korea, and evaluated potential health risks among local residents. Soils near the mines exceeded the soil quality standard values of Cu, As, and Zn contamination. The concentrations of Cd, Cu, Pb, and Zn in crop samples collected from the study area were significantly higher than those of the reference area. Some rice samples collected from the study area exceeded the maximum permissible level of 0.2xa0mg Cd/kg. The intake of rice was identified as a major contributor (≥75%) to the estimated daily intake among the residents. The average estimated daily intakes of metals were, however, below the provisional tolerable daily intake.

Investigation on Health Effects of an Abandoned Metal Mine

To investigate potential health risks associated with exposure to metals from an abandoned metal mine, the authors studied people living near an abandoned mine (n=102) and control groups (n=149). Levels of cadmium, copper, arsenic, lead, and zinc were measured in the air, soil, drinking water, and agricultural products. To assess individual exposure, biomarkers of each metal in blood and urine were measured. β2-microglobulin, α1-microglobulin, and N-acetyl-beta-glucosaminidase and bone mineral density were measured. Surface soil in the study area showed 2-10 times higher levels of metals compared to that of the control area. Metal concentrations in the groundwater and air did not show any notable differences between groups. Mean concentrations of cadmium and copper in rice and barley from the study area were significantly higher than those of the control area (p<0.05). Geometric means of blood and urine cadmium in the study area were 2.9 µg/L and 1.5 µg/g Cr, respectively, significantly higher than those in the control area (p<0.05). There were no differences in the levels of urinary markers of early kidney dysfunction and bone mineral density. The authors conclude that the residents near the abandoned mine were exposed to higher levels of metals through various routes.

Diagnostic value of antithyroid peroxidase antibody for incidental autoimmune thyroiditis based on histopathologic results

Detection of antithyroid peroxidase antibody (TPOAb) is widely used in the diagnosis of autoimmune thyroiditis (AIT), but no research has evaluated the diagnostic accuracy of TPOAb detection using histopathologic reference standards. To fill this research gap, this study assessed the diagnostic accuracy of detection of TPOAb and that of other serological markers in asymptomatic patients who had been diagnosed with AIT by histopathologic analysis after thyroid surgery. After review of patient records, 598 patients who had undergone thyroid nodule surgery were enrolled for examination for thyroid parenchyma by a pathologist and classification into no co-existing lymphocytic thyroiditis, Hashimoto thyroiditis, or non-Hashimoto type of lymphocytic thyroiditis (NHLT). The correlation between patient serological data and thyroid parenchyma pathology was analyzed. Statistically significant differences (Pxa0<xa00.05) were found between co-existing lymphocytic thyroiditis and no co-existing lymphocytic thyroiditis groups regarding thyroid-stimulating hormone (TSH) and TPOAb levels. And, TPOAb titer was significantly associated with the degree of inflammation. An abnormal TPOAb titer was found in 86 of the 598 patients (14.4xa0%) and the specificity of TPOAb detection for AIT diagnosis was found to be 96.9xa0%. The prevalence of Hashimoto thyroiditis and NHLT in the 560 papillary thyroid cancer (PTC) patients was found to be 7.9 and 17.9xa0%, respectively. The results indicate that TPOAb titer is associated with the degree of thyroid inflammation and that detection of TPOAb is a very specific means of diagnosing AIT. The results also indicate that the incidence of AIT and PTC coexistence is relatively high.

The Prevalence and Features of Thyroid Pyramidal Lobes as Assessed by Computed Tomography

BACKGROUNDnThe pyramidal lobe is an accessory lobe of the thyroid gland. The prevalence of the pyramidal lobe in thyroid glands and its features have been studied in autopsy series but there is little information regarding its parameters in patients or normal subjects. The purpose of the current study was to assess the frequency, location, and size of the pyramidal lobe using computed tomography (CT) of the neck.nnnMETHODSnFrom January to December 2010, 327 patients who underwent neck CT for trauma, thyroid cancer, pharyngolaryngeal malignancy, a palpable neck mass, cervical lymphadenopathy, and vocal cord paralysis were enrolled in the study. Their neck CTs were retrospectively analyzed by a single radiologist. Small pyramidal lobes (<9u2009mm) were not included in the study.nnnRESULTSnA pyramidal lobe was present in 41.3% (135/327) of the patients; some pyramidal lobes showed complete separation from the thyroid gland (12.6%, 17/135). There was no difference in the frequency of pyramidal lobe detection by gender (p>0.05, Fishers exact test). The pyramidal lobe predominantly originated from the left thyroid gland in 54.1% (73/135) of patients. There were two patients in whom the pyramidal lobe was located bilaterally (one case from both the right and left sides of the thyroid gland and one case from the left side and midline of the thyroid gland). The average length and volume of the pyramidal lobes were 25.0u2009mm and 129.4u2009mm(3), respectively. The upper margin of the pyramidal lobe was most commonly located at the level of the thyroid cartilage.nnnCONCLUSIONnThe prevalence of the pyramidal lobe in the left lobe of the thyroid gland is somewhat greater than 50% using the criteria employed in this study. Neck CT is useful for detecting the presence, size, configuration, and location of the pyramidal lobe.

Peripheral arterial involvement in Behcet’s disease: an analysis of the results from a Korean referral center

The purposes of this study are to review the results of endovascular and surgical interventions and to evaluate clinical appearances of recurrent arterial involvement in patients with peripheral arterial Behçet disease (BD). A total of 28 patients with peripheral arterial BD were identified. There were 24 males (85.7xa0%), with mean age of 40.0xa0±xa09.0xa0years (range 21–59). Arterial involvements were confirmed with computed tomography angiography, magnetic resonance image angiography, or ultrasound. Immunosuppressive agents were administrated to all patients. Indications of intervention were acute symptoms due to arterial occlusion and aneurysmal changes with or without rupture. Among 28 patients with peripheral arterial BD, 10 endovascular and 24 surgical interventions were performed in 21 patients. All 21 patients who underwent endovascular and surgical intervention were followed up for a mean duration of 78.7xa0±xa052.5xa0months (range 0–182xa0months). There was one mortality due to the rupture of pseudoaneurysm in patient who underwent stent-graft insertion for abdominal aortic aneurysm. New arterial involvements of BD occurred in 10 patients. All patients were male, and median age was 33.5xa0years (range 29–59xa0years). Mean time of onset of the new arterial lesion was 32.7xa0±xa032.1xa0months. In conclusion, the result of endovascular and surgical interventions is satisfactory in patients with acute peripheral arterial BD. Accurate diagnosis with immunosuppressive therapy is mandatory to prevent recurrence and activation of peripheral arterial BD.

The relationship between depressive symptoms among female workers and job stress and sleep quality

ObjectiveRecently, workers mental health has become important focus in the field of occupational health management. Depression is a psychiatric illness with a high prevalence. The association between job stress and depressive symptoms has been demonstrated in many studies. Recently, studies about the association between sleep quality and depressive symptoms have been reported, but there has been no large-scaled study in Korean female workers. Therefore, this study was designed to investigate the relationship between job stress and sleep quality, and depressive symptoms in female workers.MethodsFrom Mar 2011 to Aug 2011, 4,833 female workers in the manufacturing, finance, and service fields at 16 workplaces in Yeungnam province participated in this study, conducted in combination with a worksite-based health checkup initiated by the National Health Insurance Service (NHIS). In this study, a questionnaire survey was carried out using the Korean Occupational Stress Scale-Short Form(KOSS-SF), Pittsburgh Sleep Quality Index(PSQI) and Center for Epidemiological Studies-Depression Scale(CES-D). The collected data was entered in the system and analyzed using the PASW (version 18.0) program. A correlation analysis, cross analysis, multivariate logistic regression analysis, and hierarchical multiple regression analysis were conducted.ResultsAmong the 4,883 subjects, 978 subjects (20.0%) were in the depression group. Job stress(OR=3.58, 95% CI=3.06-4.21) and sleep quality(OR=3.81, 95% CI=3.18-4.56) were strongly associated with depressive symptoms. Hierarchical multiple regression analysis revealed that job stress displayed explanatory powers of 15.6% on depression while sleep quality displayed explanatory powers of 16.2%, showing that job stress and sleep quality had a closer relationship with depressive symptoms, compared to the other factors. The multivariate logistic regression analysis yielded odds ratios between the 7 subscales of job stress and depressive symptoms in the range of 1.30-2.72 and the odds ratio for the lack of reward was the highest(OR=2.72, 95% CI=2.32-3.19). In the partial correlation analysis between each of the 7 subscales of sleep quality (PSQI) and depressive symptoms, the correlation coefficient of subjective sleep quality and daytime dysfunction were 0.352 and 0.362, respectively.ConclusionThis study showed that the depressive symptoms of female workers are closely related to their job stress and sleep quality. In particular, the lack of reward and subjective sleep factors are the greatest contributors to depression. In the future, a large-scale study should be performed to augment the current study and to reflect all age groups in a balanced manner. The findings on job stress, sleep, and depression can be utilized as source data to establish standards for mental health management of the ever increasing numbers of female members of the workplace.

Clinical outcome and predictors of treatment response in foam sodium tetradecyl sulfate sclerotherapy of venous malformations.

AbstractObjectivesTo evaluate clinical outcomes and their predictors in patients with venous malformation (VM) treated with foam sodium tetradecyl sulfate (STS) sclerotherapy.MethodsWe retrospectively evaluated clinical outcomes of foam STS sclerotherapy in 86 patients with 91 VMs to assess reduction in pain and mass after treatment. Univariate and multivariate analysis was performed to determine possible predictors of clinical outcome with foam STS sclerotherapy.ResultsA positive response of 49.5xa0% in pain reduction and 52.7xa0% in mass reduction was observed. The numerical rating scale (NRS) score improved from 4.36u2009±u20092.64 to 1.74u2009±u20091.57, and VM mass volume decreased to 41.7u2009±u200935.52xa0% of the initial size. On multivariate analysis, a high baseline NRS score (odds ratio: 1.12, 95xa0% confidence interval: 1.09–1.15) and VM location in the trunk versus the head and neck (odds ratio: 1.30, 95xa0% confidence interval: 1.00–1.69) were positive predictors of pain improvement. Minor complications occurred in 11 (12.1xa0%) patients and recurrence in 12 (13.2xa0%) patients.ConclusionsFoam STS sclerotherapy is an effective treatment in venous malformation, with low complication risk. A high baseline NRS score and location in the trunk versus the head and neck were positive predictors in improvement of pain.Key Points• Foam STS sclerotherapy is effective in VM, with low risk of complications.n • Relief of pain tends to be dramatic in patients with severe pain.n • Location of VM is a predictor of pain improvement.n • The presence of a draining vein does not affect foam sclerotherapy.

Comparison of outcomes between endovascular treatment and bypass surgery in Takayasu arteritis

Objectives: There is currently a lack of evidence regarding the optimal revascularization method for Takayasu arteritis (TA). This study compares outcomes between endovascular treatment and surgical therapy in TA patients requiring revascularization. Method: From September 1994 to January 2011, 235 patients were diagnosed with TA according to the diagnostic criteria of the 1990 American College of Rheumatology, and of these, arterial revascularizations were performed in 65 (27.7%). Symptomatic or angiographic recurrence and peri-operative use of immunosuppressive drugs were investigated by retrospectively reviewing medical records. Results: A total of 111 arterial lesions in the 65 (27.7%) patients were revascularized during the follow-up period (median 3.2 years, range 0.01–12.7 years). At the 2-year follow-up, the symptomatic recurrence rate was significantly higher in the endovascular treatment group (32.3% vs. 11.5%, p = 0.016), as was the incidence of angiographic recurrence (32.1% vs. 11.1%, p = 0.026). The symptomatic recurrence rate was not influenced by the need for peri-operative immunosuppressive drugs (20% vs. 34.1%, p = 0.34). Conclusions: In TA patients, surgical revascularization seems to be superior to endovascular treatment with regard to patency. Further investigation to identify novel and optimal arterial revascularization methods for TA patients should be undertaken.

Solid and Isoechoic Thyroid Nodules Without Malignant Sonographic Features: Comparison of Malignancy Rate According to Nodule Size, Shape and Color Doppler Pattern

This study aimed to assess the malignancy rate of solid and isoechoic thyroid nodules without malignant sonographic features (SITNs) and to compare the malignant and benign SITNs according to nodule size, shape and color Doppler pattern. Of 382 SITNs with the largest diameter ≥10 mm, nodule size, nodule shape (i.e. spherical vs. ovoid) and color Doppler pattern (i.e. scant, peripheral, central, and mixed type) of each nodule were retrospectively evaluated. A total of 114 SITNs were histopathologically confirmed by surgery (called surgical SITN) and the malignancy rate of surgical SITNs was 8.8% (10/114). There was no statistical association between the incidence of malignancy of SITNs and nodule size but the malignancy rate of spherical SITNs was higher than that of ovoid SITNs. A significant relationship between peripheral vascularity of SITNs and benignity was found but the other vascularity patterns showed no significant association with malignancy or benignity of SITNs.

Ultrasound-Guided Fine-Needle Aspiration of Thyroid Nodules Measuring Less than 5 mm: Effects on Specimen Adequacy and Diagnosis

Objective: We aimed to assess the adequacy and efficacy of ultrasound (US)-guided fine-needle aspiration (US-FNA) for small solid thyroid nodules (SSTNs) with the largest diameter <5 mm and compared these according to nodule size. Study Design: Among 656 SSTNs in 569 patients, each SSTN was classified into 1 of 4 groups according to the largest diameter: 1 mm ≤ group A < 2 mm; 2 mm ≤ group B < 3 mm; 3 mm ≤ group C < 4 mm, and 4 mm ≤ group D < 5 mm. We compared the adequacy and efficacy of US-FNA between these groups using histopathologic results as a reference standard. Results: 571 (87.0%) SSTNs were adequately sampled by US-FNA and 200 of these were histopathologically confirmed. The adequacy of US-FNA for SSTNs varied according to the nodule diameter: the smaller the nodule diameter, the lower the diagnostic adequacy. The diagnostic efficacy of US-FNA for SSTNs showed a significant relationship with nodule size: diagnostic efficacy in groups A and B was lower than in groups C and D. Conclusions: The adequacy of US-FNA for SSTNs tended to decrease with decreased nodule size, and diagnostic efficacy of US-FNA for SSTNs with the largest diameter <3 mm was lower than for those ≥3 mm.