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Jeju, South Korea

Kang Y.K.,Chungbuk National University | Byun B.J.,Chungbuk National University | Park H.S.,Cheju halla College
Biopolymers | Year: 2011

Conformational preferences and prolyl cis-trans isomerizations of the (2S,4S)-4-methylproline (4S-MePro) and (2S,4R)-4-methylproline (4R-MePro) residues are explored at the M06-2X/cc-pVTZ//M06-2X/6-31+G(d) level of theory in the gas phase and in water, where solvation free energies were calculated using the implicit SMD model. In the gas phase, the down-puckered γ-turn structure with the trans prolyl peptide bond is most preferred for both Ac-4S-MePro-NHMe and Ac-4R-MePro-NHMe, in which the C7 hydrogen bond between two terminal groups seems to play a role, as found for Ac-Pro-NHMe. Because of the C7 hydrogen bonds weakened by the favorable direct interactions between the backbone C=O and H-N groups and water molecules, the 4S-MePro residue has a strong preference of the up-puckered polyproline II (PPII) structure over the down-puckered PPII structure in water, whereas the latter somewhat prevails over the former for the 4R-MePro residue. However, these two structures are nearly equally populated for Ac-Pro-NHMe. The calculated populations for the backbone structures of Ac-4S-MePro-NHMe and Ac-4R-MePro-NHMe in water are reasonably consistent with CD and NMR experiments. In particular, our calculated results on the puckering preference of the 4S-MePro and 4R-MePro residues with the PPII structures are in accord with the observed results for the stability of the (X-Y-Gly)7 triple helix with X = 4R-MePro or Pro and Y = 4S-MePro or Pro. The calculated rotational barriers indicate that the cis-trans isomerization may in common proceed through the anticlockwise rotation for Ac-4S-MePro-NHMe, Ac-4R-MePro-NHMe, and Ac-Pro-NHMe in water. The lowest rotational barriers become higher by 0.24-1.43 kcal/mol for Ac-4S-MePro-NHMe and Ac-4R-MePro-NHMe than those for Ac-Pro-NHMe in water. © 2010 Wiley Periodicals, Inc. Biopolymers 95: 51-61, 2011.

Oh I.-H.,Korea University | Yoon S.-J.,Korea University | Seo H.-Y.,Korea University | Kim E.-J.,Cheju halla College | Kim Y.A.,Korea University
BMC Musculoskeletal Disorders | Year: 2011

Background: Musculoskeletal diseases are becoming increasingly important due to population aging. However, studies on the economic burden of musculoskeletal disease in Korea are scarce. Therefore, we conducted a population-based study to measure the economic burden of musculoskeletal disease in Korea using nationally representative data. Methods. This study used a variety of data sources such as national health insurance statistics, the Korea Health Panel study and cause of death reports generated by the Korea National Statistical Office to estimate the economic burden of musculoskeletal disease. The total cost of musculoskeletal disease was estimated as the sum of direct medical care costs, direct non-medical care costs, and indirect costs. Direct medical care costs are composed of the costs paid by the insurer and patients, over the counter drugs costs, and other costs such as medical equipment costs. Direct non-medical costs are composed of transportation and caregiver costs. Indirect costs are the sum of the costs associated with premature death and the costs due to productivity loss. Age, sex, and disease specific costs were estimated. Results: Among the musculoskeletal diseases, the highest costs are associated with other dorsopathies, followed by disc disorder and arthrosis. The direct medical and direct non-medical costs of all musculoskeletal diseases were $4.18 billion and $338 million in 2008, respectively. Among the indirect costs, those due to productivity loss were $2.28 billion and costs due to premature death were $79 million. The proportions of the total costs incurred by male and female patients were 33.8% and 66.2%, respectively, and the cost due to the female adult aged 20-64 years old was highest. The total economic cost of musculoskeletal disease was $6.89 billion, which represents 0.7% of the Korean gross domestic product. Conclusions: The economic burden of musculoskeletal disease in Korea is substantial. As the Korean population continues to age, the economic burden of musculoskeletal disease will continue to increase. Policy measures aimed at controlling the cost of musculoskeletal disease are therefore required. © 2011 Oh et al; licensee BioMed Central Ltd.

Oh I.-H.,Korea University | Yoon S.-J.,Korea University | Kim E.-J.,Cheju halla College
Journal of the Korean Medical Association | Year: 2011

The disability adjusted life year (DALY), a single indicator of the burden of disease, is widely used to measure the burden of diseases, injuries, and risk factors. In this study, we review the relative sizes of the burden of disease worldwide and the characteristics of the burden of disease of the Korean population. Future research directions for study of the burden of disease in Korea are also suggested. In the Korean population, diabetes mellitus was the leading cause of the burden of disease (970 DALYs per 100,000 population) in 2002, followed by cerebrovascular disease (937 DALYs per 100,000 population) and asthma (709 DALYs per 100,000 population), which differed with the leading causes of the burden of disease globally: unipolar depressive disorder, ischemic heart disease, and cerebrovascular disease. In 2007, cirrhosis of the liver in males and cerebrovascular disease in females became the leading causes of the burden of disease of the Korean population with the epidemiologic transition. Despite the methodological difference with global burden of disease study, these findings represent the characteristics of the burden of disease in Korea. Though many studies have been conducted to measure the burden of disease in Korea, there is a need to go beyond these to combine policymaking for resource allocation, such as cost effectiveness analysis, with burden of disease studies. © Korean Medical Association.

Kim H.-J.,Korea University | Kim Y.-A.,Korea University | Seo H.-Y.,Korea University | Kim E.-J.,Cheju halla College | And 2 more authors.
Journal of the Korean Medical Association | Year: 2012

Stroke is a disease that causes a substantial economic burden. With the rapidly aging population in Korea, the prevalence of chronic diseases, including stroke, is expected to rise, along with associated health care expenditures. Therefore, we estimated the economic burden of stroke in Korea in 2010 using nationally representative data. We used a prevalence-based approach to estimate the cost of stroke by claims data from the Korean National Health Insurance. Data from the Korea Health Panel, the Korea National Statistical Office's records of causes of death, and Labor Statistics were used to calculate direct non-medical costs and indirect costs. Direct costs included direct medical costs and direct non-medical costs, and indirect costs were opportunity costs lost due to premature death and productivity loss. Total costs were estimated by adding age- and gender-specific costs. The total economic burden of stroke was $3.53 billion: $1.87 billion for hemorrhagic stroke and $1.66 billion for ischemic stroke. The direct costs were $1.74 billion and the indirect costs were $1.79 billion. By gender, males were burdened at $2.19 billion, while females bore $1.34 billion of the total burden. Stroke imposes a huge economic burden, as indicated by the fact that the costs of stroke increased by 4.4% from 2005 to 2010, and the estimated cost was 0.35% of gross domestic product. Therefore, effective prevention programs and treatments are needed to reduce the economic burden of stroke in Korea. © Korean Medical Association.

Lee Y.-H.,Korea University | Yoon S.-J.,Korea University | Kim E.-J.,Cheju halla College | Kim Y.-A.,Korea University | And 2 more authors.
Allergy and Asthma Proceedings | Year: 2011

Understanding the magnitude of the economic impact of an illness on society is fundamental to planning and implementing relevant policies. South Korea operates a compulsory universal health insurance system providing favorable conditions for evaluating the nationwide economic burden of illnesses. The aim of this study was to estimate the economic costs of asthma imposed on Korean society. The Korean National Health Insurance claims database was used for determining the health care services provided to asthma patients defined as having at least one inpatient or outpatient claim(s) with a primary diagnosis of asthma in 2008. Both direct and indirect costs were included. Direct costs were those associated directly with treatment, medication, and transportation. Indirect costs were assessed in terms of the loss of productivity in asthma patients and their caregivers and consisted of morbidity cost, mortality cost, and caregivers' time cost. The estimated cost for 2,273,290 asthma patients in 2008 was $831 million, with an average per capita cost of $336. Among the cost components, outpatient and medication costs represented the largest cost burden. Although the costs for children accounted for the largest proportion of the total cost, the per capita cost was highest among patients ≥50 years old. The economic burden of asthma in Korea is considerable. Considering that the burden will increase with the rising prevalence, implementation of effective national prevention approaches aimed at the appropriate target populations is imperative. Copyright © 2011, OceanSide Publications, Inc.

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