• Toxicological Research
• /
• v.17
• /
• pp.47-57
• /
• 2001

Alzheimer's disease (AD) is the most common cause of dementia in the elderly, and its pathology is characterized by the presence of numerous numbers of senile plaques and neurofibrillary tangles. Several genetic and transgenic studies have indicated that excess amount of $\beta$-amyloid protein (A$\beta$) is produced by mutations of $\beta$TEX>$\beta$-amyloid precursor protein and causes learning impairment. Moreover, $A\beta$ has a toxic effect on cultured nerve cells. To prepare AD model animals, we have examined continuous (2 weeks) infusion of $A\beta$ into the cerebral ventricle of rats. Continuous infusion of $A\beta$ induces learning impairment in water maze and passive avoidance tasks, and decreases choline acetyltransferase activity in the frontal cortex and hippocampus. Immunohistochemical analysis revealed diffuse depositions of $A\beta$ in the cerebral cortex and hippocampus around the ventricle. Furthermore, the nicotine-evoked release of acetylcholine and dopamine in the frontal cortex/hippocampus and striatum, respectively, is decreased in the $A\beta$-infused group. Perfusion of nicotine (50 $\mu\textrm{M}$) reduced the amplitude of electrically evoked population spikes in the CA1 pyramidal cells of the control group, but not in those of the $A\beta$-infused group, suggesting the impairment of nicotinic signaling in the $A\beta$-infused group. In fact, Kd, but not Bmax, values for ［$^3H$］ cytisine binding in the hippocampus significantly increased in the $A\beta$-infused rats. suggesting the decrease in affinity of nicotinic acetylcholine receptors. Long-term potentiation (LTP) induced by tetanic stimulations in CA1 pyramidal cells, which is thought to be an essential mechanism underlying learning and memory, was readily observed in the control group, whereas it was impaired in the $A\beta$-infused group. Taken together, these results suggest that $A\beta$ infusion impairs the signal transduction mechanisms via nicotinic acetylcholine receptors. This dysfunction may be responsible, at least in part, for the impairment of LTP induction and may lead to learning and memory impairment. We also found the reduction of glutathione- and Mn-superoxide dismutase-like immunoreactivity in the brains of $A\beta$-infused rats. Administration of antioxidants or nootropics alleviated learning and memory impairment induced by $A\beta$ infusion. We believe that investigation of currently available transgenic and non-transgenic animal models for AD will help to clarify the pathogenic mechanisms and allow assessment of new therapeutic strategies.

• Archives of design research
• /
• v.18 no.1 s.59
• /
• pp.175-184
• /
• 2005

With the rapid progress of the aging society in Korea, the silver generation is emerging as another class of users in the new population structure. This is a social issue to be dealt with, and the effect of such a change is being observed dearly in the design area. In addition, there are increasing demands for consideration of minor groups of users including the elderly, the disabled, the left-handed, children and pregnant women and nursing mothers, who have been treated as the weak. Such a human-centered idea may be the manifestation of the recovery of humanity and the self-realization of human beings through experiences and reflections of the industrial society of the past. The present study examined the tendency of design standardization centering on universal design, which has emerged in response to user-centered social needs, and suggested general considerations for the necessity of introducing such standards. These days the meanings of standardization are not limited to quality, performance, safety and economic aspect. Standardization is required to consider the diversity and the welfare of human beings. In addition, one of the important functions of standardization is to provide designers with important clues and guidelines for designing. In reality, however, standardization has been rejected by the circle of design for the reason that it deters free creation, so research on the introduction of standardization has been at standstill. As ISO/IEC Guide71 was published in November 2001, based on which, the Korea Standards Association established KS A ISO/IEC Guide71 without changing its contents. In companies' manufacturing activities, the progress of standardization in connection to universal design is growing more important. However, usefulness and interchangeability for the absolute majority resulting from standardization are incomparable. Lastly, the realization of universal design requires human-centered design mind, based on users' experiences and needs, the characteristics of the human bodies and inconvenient elements rather than standards for the sake of standardization.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.6
• /
• pp.3751-3758
• /
• 2014

This study was designed to evaluate the effects of arthritis and comorbid chronic conditions on the health-related quality of life (HRQoL) in the Korean older population. The study subjects were 2,708 Korean adults aged 65 and older from the $3^{rd}$ Korea National Health and Nutrition Examination Surveys data: 1,357 persons with a single chronic condition, such as arthritis, herniations of the intervertebral disc, osteoporosis, asthma, peptic ulcers, stroke, or cataract; 886 persons with arthritis and a second chronic condition described above; and 465 persons with no chronic condition. An analysis of covariance was performed to compare the EQ-5D index among the groups. The effects of arthritis, second chronic condition and their interactions were analyzed by multiple linear regression analysis. The results are as follows. Compared to men with arthritis only, men with stroke only, stroke and arthritis, or cataract and arthritis had a lower age adjusted EQ-5D index. Women with a stroke only, asthma only, cataract only, osteoporosis and arthritis, peptic ulcer and arthritis, stroke and arthritis, or cataract and arthritis had a lower age adjusted EQ-5D index than women with arthritis only. Arthritis and comorbid conditions had additive effects on the HRQol in both genders except for arthritis and stroke in women. In conclusion, comorbid chronic medical conditions in older people with arthritis may reduce the HRQoL in an additive manner.

• KIISE Transactions on Computing Practices
• /
• v.23 no.6
• /
• pp.371-378
• /
• 2017

In modern society, awareness of diabetes is growing with an increase in the elderly population and an increase in the incidence of diabetes. In particular, diabetic patients can suddenly develop hypoglycemic shock; therefore, it is important to measure blood glucose periodically. However, self-monitoring blood glucose meters are difficult to carry and it is difficult to manage the value. To solve these problems, the blood glucose measurement system has been developed as a sensor attached to the body or as one of the functions of smart devices, but it has not been commercialized. In this paper, we propose a smart band with a blood glucose measurement function. If a user enters a schedule to measure blood glucose level, such as before/after meals, in the app, he/she can receive a measurement alarm from the band. The user can measure the blood glucose level at any time using the band, and the measured value is transmitted and managed by the app including behavior history such as before/after meals and the time. This will help the user to manage, diagnose and prevent health problems. The system has been tested using two medical device-certified products, and each blood glucose measurement value has been confirmed to be more accurate.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.5 no.1
• /
• pp.17-25
• /
• 2011

This paper aims to find the optimal control gain for enhancing the convenience of electric walking frames and design a control algorithm. With the recent advances in medical technology, there has been a rapid increase in the aging population and a variety of mobile walking frames have been developed for improvement of the quality of life. However, the manual walking frames of such mobile aids don't have any electric motor which helps facilitate elderly users' walking and thus are not efficient enough for the old people of weak strength to use especially when moving on uneven surfaces such as slopes or thresholds. The types of electric walking frames have been developed to overcome such inefficiency. Electric walking frames require users' control operations for motor driving unlike manual frames. Therefore, when they are not properly handled, it causes considerable inconvenience to their users. The present study compared the electric walking frames with manual ones in terms of operational convenience and attempted to improve the user convenience of walking frames varying the control value for user convenience based on certain standards. This paper presented a haptic sensor designed to recognize the will to walk and measure the degree of convenience and proposed a control algorithm for improvement of convenience. For user convenience, this paper evaluated the relative convenience of walking frames in view of changing differences between the center of vehicle (COV) and the center of position (COP). With the employment of an electric walking frame and a new measuring method, all the processes were experimentally tested and validated.

• Genomics & Informatics
• /
• v.9 no.3
• /
• pp.121-126
• /
• 2011

Osteoarthritis (OA) is the most common degenerative joint disorder in the elderly population. To identify OA-associated genetic variants and candidate genes, we conducted a genome-wide association study (GWAS). A total 3,793 samples (476 cases: wrist + knee and 3317 controls) from a community-based epidemiological study were genotyped using the Affymetrix SNP 5.0. An intronic SNP (rs4789934) in the TIMP2 (tissue inhibitor of metalloproteinase-2) showed the most significance with OA (odd ratio [OR] = 2.06, 95% confidence interval [CI] = 1.52-2.81, p = $4.01{\times}10^{-6}$). Furthermore, a poly-morphism (rs1352677) in the NKAIN2 ($Na^+/K^+$ transporting ATPase interacting 2) was suggestively associated with OA (OR = 1.43, CI = 1.22-1.66, p = $7.01{\times}10^{-6}$). The present study provides new insights into the identification of genetic predisposing factors for OA.

• Journal of the Korea Convergence Society
• /
• v.10 no.12
• /
• pp.337-343
• /
• 2019

The need for preparation for old life has been further increased due to the increase of the elderly population and changes in economic conditions today. The purpose of this study is to analyze the relationship between income instability and the degree of preparation for old life and satisfaction of current life. The key variables were extracted through prior study review. And the data collected through the survey were statistically analyzed with a structural equation model. The analysis found that the indirect effect of the current income risk on the satisfaction of current life through the preparation for old life had a significant negative effect under the statistically significant level of 0.05. However, it was found that the direct effects of current income risk on the satisfaction of current life were not statistically significant. An additional analysis was conducted by dividing the age, the number of dependents by two groups respectively. To summarize the results, preparation for old life played a significant role as a prerequisite for improving the satisfaction of current life. And the variability(risk) of current income played an important role in preparing for old life. At this time, the degree of relevance between the factors(potential variables) differed somewhat between the two groups. The results of this analysis will be meaningful in providing basic source of data to prepare for a satisfactory life in each individual's current situation. This study, meanwhile, has limitations that have only been done with cross-sectional analysis and would like to analyze time-series changes in the future.

• The Journal of Korean Academy of Prosthodontics
• /
• v.58 no.2
• /
• pp.95-102
• /
• 2020

Purpose:The aim of the present study was to evaluate the incidence of the second mesiobuccal (MB2) canal, root fusion, and C-shaped root canal configuration in the Korean maxillary first (MM1) and second (MM2) molars by analyzing cone-beam computed tomographic (CBCT) images. Materials and methods: Patients undergoing presurgical CBCT examination were included in the current study. The CBCT images of 1498 MM1 and 1742 MM2 from 1658 Korean patients were assessed to determine the incidence of a MB2 canal, the types of canal configurations, root fusion, and C-shaped root canal configurations. Further, the correlations between the incidence of MB2 canal and age, gender, and tooth position were analyzed. Results: The study population was relatively old (mean age: 66.1 years). The percentage of MB2 canals in MB roots was 60.1% and 28.0% in MM1 and MM2, respectively, with the most common configurations being Weine type III in MM1 and Weine type II in MM2. Additionally, the frequency of a MB2 canal decreased with age in both molars and was higher in men than in women in the MM1 only. Furthermore, root fusion was present in 2.3% and 26.2% of the MM1 and MM2, respectively, whereas C-shaped root canals were observed in 0.4% and 2.7% of the MM1 and MM2, respectively. Conclusion: The MB2 canal was found more frequently in the MM1, whereas root fusion and C-shaped root canals were both seen more frequently in the MM2.

• Tuberculosis and Respiratory Diseases
• /
• v.79 no.3
• /
• pp.111-120
• /
• 2016

Asthma is a prevalent and serious health problem in Korea. Recently, the Korean Asthma Guideline has been updated by The Korean Academy of Tuberculosis and Respiratory Diseases (KATRD) in an effort to improve the clinical management of asthma. This guideline focuses on adult patients with asthma and aims to deliver up to date scientific evidence and recommendations to general physicians for the management of asthma. For this purpose, this guideline was updated following systematic review and meta-analysis of recent studies and adapting some points of international guidelines (Global Initiative for Asthma [GINA] report 2014, National Asthma Education and Prevention Program [NAEPP] 2007, British Thoracic Society [BTS/SIGN] asthma guideline 2012, and Canadian asthma guideline 2012). Updated issues include recommendations derived using the population, intervention, comparison, and outcomes (PICO) model, which produced 20 clinical questions on the management of asthma. It also covers a new definition of asthma, the importance of confirming various airflow limitations with spirometry, the epidemiology and the diagnostic flow of asthma in Korea, the importance and evidence for inhaled corticosteroids (ICS) and ICS/formoterol as a single maintenance and acute therapy in the stepwise management of asthma, assessment of severity of asthma and management of exacerbation, and an action plan to cope with exacerbation. This guideline includes clinical assessments, and treatment of asthma-chronic obstructive pulmonary disease overlap syndrome, management of asthma in specific conditions including severe asthma, elderly asthma, cough variant asthma, exercise-induced bronchial contraction, etc. The revised Korean Asthma Guideline is expected to be a useful resource in the management of asthma.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.15 no.1
• /
• pp.247-257
• /
• 2020

In recent years, the proportion of youth's self-employed is steadily increasing, and government policy also actively encourages youth to become an entrepreneur. However, most of the domestic precedent studies on the self-employed labor market focus on the middle-aged and the elderly, and previous studies on the self-employed labor market of young people are hardly ever studied. Above all, the study that examines the factors of entry into self-employment of young people is not sufficient and researchers usually utilize the study about for all ages to explain the self-employment market of young people. However, because the young and middle-aged people differ in labor market conditions, family backgrounds, and the level of accumulation of human capital, separate explanations and theories are needed. Therefore, this study explored the factors of entry into self-employment by separating the age group from 15~29 years old. The data used in the analysis was the 9th to 20th data of the Korea Labor Panel Survey. The youth unemployment rate and employment rate were referred to the Economically Active Population Survey of Statistics Korea. The analysis subject was limited to young people who are currently performing economic activities, and the analysis method used multi-level logit model. The main results are summarized as follows. First, the lower the unemployment rate and the higher the employment rate, the younger people tend to enter their own businesses on the structural level. Second on the individual level, young people who possess enough financial capital or pursuit personal aptitude or interest tend to enter self-employment. However, there are no statistical effects of human capital and entrepreneur capital.