Hwang, Gyeongyeon;Ji, Yewon;Yoon, Hakyoung;Lee, Sang Jun
IEMEK Journal of Embedded Systems and Applications
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v.17
no.5
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pp.265-272
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2022
As the risk of lung cancer has increased, early-stage detection and treatment of cancers have received a lot of attention. Among various medical imaging approaches, computer tomography (CT) has been widely utilized to examine the size and growth rate of lung nodules. However, the process of manual examination is a time-consuming task, and it causes physical and mental fatigue for medical professionals. Recently, many computer-aided diagnostic methods have been proposed to reduce the workload of medical professionals. In recent studies, encoder-decoder architectures have shown reliable performances in medical image segmentation, and it is adopted to predict lesion candidates. However, localizing nodules in lung CT images is a challenging problem due to the extremely small sizes and unstructured shapes of nodules. To solve these problems, we utilize atrous spatial pyramid pooling (ASPP) to minimize the loss of information for a general U-Net baseline model to extract rich representations from various receptive fields. Moreover, we propose mixed-up attention mechanism of reverse, boundary and convolutional block attention module (CBAM) to improve the accuracy of segmentation small scale of various shapes. The performance of the proposed model is compared with several previous attention mechanisms on the LIDC-IDRI dataset, and experimental results demonstrate that reverse, boundary, and CBAM (RB-CBAM) are effective in the segmentation of small nodules.
Background: Truck driving is a highly sedentary occupation that places workers at risk for chronic health conditions, such as obesity and high blood pressure. The primary purpose of this study was to objectively describe truck drivers' typical physical activity (PA) patterns. Methods: We used ~7-10-day baseline PA actigraphy data samples from drivers in the Safety & Health Involvement For Truckers (SHIFT) study (n = 394). Driver PA patterns (e.g., average number of ≥10 minute Freedson bouts per week, time in bouts, and common days/times for PA) were summarized with descriptive analyses. We also compared objective accelerometer data to self-reports. Results: Drivers' weekly PA averaged 14.4 minutes (SD = 37.0), and most PA occurred between 5-6 pm on Tuesdays and Wednesdays. Drivers overestimated self-reported weekly exercise by over 60 min/week compared to accelerometer data. Conclusion: Our results suggest that objective PA assessment may be warranted over self-report when possible, and timing may be key in future PA intervention work with truck drivers.
Background: Numerous studies have consistently demonstrated that depression can be associated with cognitive function decline, primarily focusing on older adults due to the neurodegenerative characteristics of dementia. With persistent depression frequently reported in patients with early-onset or young-onset dementia, this study aimed to assess the impact of depression, specifically the changes in depressive symptoms over time, on the risk of cognitive function decline in middle-aged adults in Korea. Methods: This retrospective study utilized data from the first four waves (2006-2012) of the Korean Longitudinal Study of Aging (KLoSA), focusing on middle-aged adults with normal cognitive function at baseline. Changes in depressive symptoms were categorized into four groups based on the CES-D score, and their association with cognitive function decline was evaluated using a multivariate logistic regression model. Results: Of the initial 10,254 participants, 3,400 were included in the analysis. Depressive status, particularly newly onset (adjusted odds ratio [aOR] 1.96; 95% confidence interval [CI] 1.32-2.93) and persistent depression groups (aOR 5.59; 95% CI 2.90-10.78), were significantly associated with cognitive function decline. In contrast, recovery from depressive symptoms was not significantly associated with cognitive function decline (p=0.809). Conclusions: Our study showed a significant association between changes in depressive symptoms and cognitive function decline in middle-aged Korean adults. This suggests that management of depressive symptoms could be crucial for the prevention of cognitive function decline in this population.
Hypogonadism is associated with an increased risk of coronary artery disease. This study sought to describe the histomorphology of the left coronary arteries of the adult male rabbit following orchiectomy and subsequent testosterone administration. We included 20 adult male rabbits, divided into a baseline group (n=2), an interventional group subjected to castration only (n=6), an intervention group subjected to castration followed by testosterone injection (n=6), and a control group (n=6). Key variables under investigation were serum testosterone levels, the intima-media thickness of coronary arteries, smooth muscle cell density, and adventitial collagen fiber density. The mean coronary arteries' intimal medial thickness was significantly higher in the castrated group than in controls (0.488 mm and 0.388 mm, respectively), while the testosterone-injected group had a mean of 0.440 mm. Mean smooth muscle cell density was significantly lower in the castrated rabbits vs. controls (26.96% and 47.80%, respectively), this observation being reversed with testosterone injection (47.53%). Mean adventitial collagen fiber density was significantly higher in the castrated group than in controls (66.6% and 36.1%, respectively), with a marginal difference after testosterone injection (65.2%). This study demonstrates that castrationinduced hypogonadism causes morphological changes in the coronary arteries that are partly reversible using testosterone injections. These findings provide a morphological basis for understanding the role of testosterone in coronary arteries.
Kim, Dae-Sung;Kim, Dong-Hyun;Bae, Jong-Myun;Shin, Myung-Hee;Ahn, Yoon-Ok;Lee, Moo-Song
Journal of Preventive Medicine and Public Health
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v.32
no.4
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pp.452-458
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1999
Objectives: The authors conducted the study to evaluate bias when potentially diseased subjects were included in cohort members while analyzing risk factors of chronic liver diseases. Methods: Total of 14,529 subjects were followed up for the incidence of liver diseases from January 1993 to June 1997. We have used databases of insurance company with medical records, cancer registry, and death certificate data to identify 102 incident cases. The cohort members were classified into potentially diseased group(n=2,217) when they were HBsAg positive, serum GPT levels higher than 40 units, or had or has liver diseases in baseline surveys. Cox's model were used for potentially diseased group, other members, and total subjects, respectively. Results: The risk factors profiles were similar for total and potentially diseased subjects: HBsAg positivity, history of acute liver disease, and recent quittance of smoking or drinking increased the risk. while intake of pork and coffee decreased it. For the potentially diseased, obesity showed marginally significant protective effect. Analysis of subjects excluding the potentially diseased showed distinct profiles: obesity increased the risk, while quitting smoking or drinking had no association. For these intake of raw liver or processed fish or soybean paste stew increased risk; HBsAg positivity, higher levels of liver enzymes and history of acute liver diseases increased the risk. Conclusions: The results suggested the potential bias in risk ratio estimates when potentially diseased subjects were included in cohort study on chronic liver diseases, especially for lifestyles possibly modified after disease onset. The analytic strategy excluding potentially diseased subjects was considered appropriate for identifying risk factors for chronic liver diseases.
Postmenopausal women are at an increased risk of developing coronary artery disease. This is due to primarily dyslipidemia accompanying the loss of estrogen secretion. Soy isoflavones are known to have weak estrogenic effects. The purpose of this study is to investigate whether isoflavone supplement improves the risk of cardiovascular disease in hypercholesterolemic postmenopausal women. Subjects consisted of 39 Korean postmenopausal women with hypercholesterolemia (total cholesterol $\geq$ 200 mg/㎗ or LDL cholesterol $\geq$ 130 mg/㎗). Subjects were divided into 2 groups; placebo group (PG), isoflavone supplement group (IG). During 12 weeks, subjects were given placebo and 80mg isoflavone daily. Anthropometric measurement, blood sample analysis and dietary intake measurement were taken at baseline and after 12 weeks. After 12 weeks, systolic blood pressure was decreased significantly (p < 0.01) and plasma HDL cholesterol level was increased significantly (p < 0.05) in IG. But there were no significant changes in plasma total cholesterol, LDL cholesterol and triglyceride levels after isoflavone supplementation. There was a negative correlation between initial plasma HDL cholesterol level and the extent of plasma HDL cholesterol reduction in IG (r=-0.572, p=0.012). Atherogenic index (AI), total-/LDL- cholesterol ratio and LDL/HDL cholesterol ratio were improved significantly after isoflavone supplementation. In subjects whose initial plasma LDL cholesterol level were above 160 mg/㎗, plasma malondialdehyde (MDA) level were decreased and total antioxidant status (TAS) were increased significantly after isoflavone supplement (p < 0.05). However there were no significant changes in flow-mediated dilator (FMD), the marker of endothelium-dependent vasodilation and nitroglycerine-mediated dilator (NMD), the marker of endothelium-independent vasodilation and the extent of DNA damage after isoflavone supplement. In conclusion, these results indicate that isoflavone supplement may decrease the risk of cardiovascular disease via improving blood pressure, HDL cholesterol level and AI in hypercholesterolemic postmenopausal women. Futhermore, in case of subjects with elevated LDL cholesterol level, isoflavone supplementation may have more antiatherogenic effects via improving antioxidant status.
The purpose of this study was to find out the effects of a 12-week aerobic exercise plus lifestyle modification on obese-induced metabolic syndrome in obese adolescent girls. A total of 52 obese adolescent girls (13-14 years old; body mass index (BMI) ${\geq}$95th percentiles for age and sex) purposely assigned to aerobic exercise group (AEG, n=15), aerobic exercise plus lifestyle modification group (ALG, n=18), or control group (CG, n=19). The AEG completed 12 weeks of walking exercise (30-60 min/day, 65-75% HRmax, 6 days/week), the ALG completed 12 weeks of walking exercise (30-60 min/day, 65-75% HRmax, 6 days/week) and behavior modification (60 min/day, 1 day/week), and the CG continued their normal life. The presence of the metabolic syndrome and component risk factors were determined before and after 12-week programs. The total prevalence of the metabolic syndrome was 48.1% in this sample (25/52) of participants at baseline. After the programs the prevalence of the metabolic syndrome was improved in the AEG and ALG 33.3, 27.8%, respectively. Group analyses showed significant difference in risk factors of the metabolic syndrome such that the AEG and ALG had significantly greater improvements in waist circumference, triglycerides, blood glucose and systolic blood pressure than the CG, while there were no significant difference in HDL cholesterol and diastolic blood pressure. Also there was no group difference between AEG and ALG in all measured metabolic risk factors after the programs. These results indicate that the positive changes of the ALG were not associated with lifestyle modification (behavior modification) but associated with aerobic exercise. However, long-term follow up studies are necessary to clarify the additive effect of the behavior modification on the metabolic syndrome.
Paek, Yu-Jin;Lee, Sungkyu;Kim, Yun-Hee;Lee, Kang-Sook;Yim, Hyeon-Woo;Kim, Myung-Shig;Kim, Cheol-Hwan;Jeung, Ok
Asian Pacific Journal of Cancer Prevention
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v.15
no.12
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pp.4963-4968
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2014
Background: We evaluated whether providing health risk appraisal for Koreans (KHRA) in terms of 'health age' during smoking cessation program would effectively help smokers quit smoking or not. Materials and Methods: A total of 332 male smokers aged between 30-65 years old, registered for a smoking cessation program in a public health center in a city, were recruited and underwent a baseline survey from January 2010 to February 2011. They were then prospectively randomized to a conventional counseling group (n=165) or a KHRA group (n=167), and received conventional counseling or KHRA-based counseling for six months. Abstinence rates were identified through carbon monoxide measurement (at the $4^{th}$ and $24^{th}$ weeks) or urinary cotinine level (at the $12^th$ week). Results: The abstinence rate confirmed by exhaled carbon monoxide was significantly higher in the KHRA group (61.1%) than the control group (49.1%) at the $4^{th}$ week (absolute difference 12.0%, 95% CI: 1.4%-22.6%). However, there was no difference in abstinence rates between the two groups at the 12th and 24th weeks. The predicting factors of 24 week's smoking cessation success were age, older than 50 years old (OR 2.02, 95% CI: 1.16-3.52), lower Fagerstr$\ddot{o}$m Test for Nicotine Dependence score less than 4 (OR 1.84, 95% CI: 1.03-3.29), and higher Self Efficacy/Temptation score (OR 1.79, 95% CI: 1.05-3.06). Conclusions: Smoking cessation counseling with KHRA could be effective compared to conventional counseling in the short period of smoking cessation. Further study is needed to evaluate the long-term efficacy of KHRA in tobacco dependence treatment and to establish the indication and target population of this tool.
To determine the effects of endogenous and exogenous strogen on serum lipid levels, twenty nonsmoking healthy Korean women were participated in this experiment for 12 weeks. They were assigned to three groups : (1) eight women aged 22 to 30(yr) for the premenopausal(Pre) group, (2) eight, aged 49 to 60(yr) for the postmenoparusal(Pst) group, (3) four, aged 23 to 30(yr) for the oral contraceptive(OC) group which used triphasic OC formulation. Fasting blood samples representing every phase of the hormonal levels were obtained from the subjects of the Pre and the OC group. From the subjects of the Pst group, fasting blood samples were obtained once per three weeks for 12 weeks. All the serum data were adjusted for dietary effects, exercise, personality type and body mass index(BMI) by using analysis of covariation(ANCOVA). Serum lipid levels of the three groups were significantly different. While serum levels of triglycerides(TG)(p<0.0001), low density lipoprotein-chloesterol(LDL-C)/high density liporotein-cholesterol(HDL-C) ratio (LDC-C/HDL-C)(P<0.01) and total cholesterol (TC)/HDL-C ratio (TC/HDL-C)(P<0.001) were significatnly high in the Pst group, serum HDL-C(P0.001) level was significantly high in the Pre group. The OC group showed significantly low serum TC(P<0.0001) and LDL-C(P<0.0001) levels. There was no signidicant difference in the fluictuation of serum lipid levels during the menstrual cycle of the Pre group. However, in the OC group, serum TG level was significantly increased at phase 2(P<0.05) where exogenous estrogen administration was highest. Even though other serum lipid levels of the OC group were not significantly fluctuated according to the exogenous estrogen administration, there was a trend of increased levels of serum TC, LDL-C, LDL-C/HDL-C and TC/HDL-C and decreased level of HDL-C during the menstruation period. Also, serum TC level was high(P<0.005) and serum TG level was low (P<0.005) at the baseline of the OC group compared with the periods of OC administration. When screening and counseling the female population at risk for coronary heart disease(CHD), the result of this study suggest that in may be desirable to divide the population into several groups according to their personal physiological characteristics, such as age, OC administration, menstrual cycle and menopause, as well as general risk factors for CHD.
Purpose : Impaired glucose tolerance (IGT) was standardized in 1979 by the National Diabetes Data Group and the World Health Organization as a risk factor for type 2 diabetes, replacing groups such as 'borderline' and 'chemical' diabetes. The main clinical significance of IGT is as a risk factor for type 2 diabetes and as a risk factor for cardiovascular disease and as a component of the metabolic syndrome. In 1997 the American Diabetes Association(ADA) was proposed the new classification and diagnostic criteria for diabetes, which is strict with the diagnostic baseline of Diabetes from 140mg/dl to 126mg/dl. And it's main purpose is to prevent chronic complications by early diagnosis and treatments. In the oriental medicine, Supungsunkihwan has been used in treatments of Diabetes including IGT & NIDDM, however there is not enough studies about the its objective hypoglycemic effect. so in order to investigate whether there is hypoglycemic effect of Supungsunkihwan, clinical studies were performed with IGT and mild NIDDM patients. Methods : Prior to the study, fasting blood sugar(FBS) and postprandial 2hrs(PP2hrs) glucose were checked. In addition, ECG, cholesterol, TG, HbA1c levels were measured, and the dinical characteristics of patients that can be influence to the blood sugar level such as age, gender, rest type, diet type were surveyed. Supungsukihwan was administered for 7 days, and FBS & PP2hrs were measured again after the therapy. Result : PP2hrs glucose levels were decreased by the administration of Supungsunkihwan. And It's hypoglycemic effects has the correlation with age. That is, the more age increase, the more hypoglycemic effect decrease. Conclusion : Supungsukihwan has hypoglycmic effects on IGT & mild NIDDM patients and it is more effective when administrated to young patients relatively.
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