Biomedical subjects

Y L Chuang

Publications and source records attributed to Y L Chuang.

7 recordsLinked to original sources

PubMed2006

Self-propelled particles with soft-core interactions: patterns, stability, and collapse.

Understanding collective properties of driven particle systems is significant for naturally occurring aggregates and because the knowledge gained can be used as building blocks for the design of artificial ones. We model self-propelling biological or artificial individuals interacting through pairwise attractive and repulsive forces. For the first time, we are able to predict stability and morphology of organization starting from the shape of the two-body interaction. We present a coherent theory, based on fundamental statistical mechanics, for all possible phases of collective motion.

Journal Article↗

PubMed2006

Posterior epidural migration of a sequestrated lumbar disk fragment: MR imaging findings.

We present a 75-year-old man who, for 2 weeks, had progressive pain in both of his thighs when standing straight. MR imaging showed a sequestrated disk fragment, which had a signal intensity similar to that of a herniated disk with a rim enhancement in the posterior epidural space and a ruptured outermost annulus of the intervertebral disk at L2-3. Awareness of these MR imaging findings can help in the diagnosis of posterior epidural disk migration.

Aged↗

PubMed2000

Activation of nuclear factor kappaB in hepatitis C virus infection: implications for pathogenesis and hepatocarcinogenesis.

The hepatitis C virus (HCV) core protein is a multifunctional protein. It may bind to the death domain of tumor necrosis factor receptor 1 (TNFR1) and to the cytoplasmic tail of lymphotoxin-beta receptor, implying that it may be involved in the apoptosis and anti-apoptosis signaling pathways. In vitro studies have been inconclusive regarding its ability to inhibit or enhance TNF-alpha-induced apoptosis. To address this issue, electrophoretic mobility shift assay (EMSA) and immunohistochemical studies were used to show the activation of nuclear factor kappaB (NF-kappaB) in HCV-infected liver tissues and in HCV core-transfected cells. The activation of NF-kappaB was correlated with the apoptosis assays. The results showed that NF-kappaB activation could be shown in HCV-infected livers and HCV core-transfected cells. The data of EMSA correlated with those of immunohistochemical studies, which revealed a higher frequency of NF-kappaB nuclear staining in HCV-infected than in normal livers. NF-kappaB activation conferred resistance to TNF-alpha-induced apoptosis in HCV core-transfected cells. Inhibition of NF-kappaB activation by pyrrolidine dithiocarbamate sensitized them to TNF-alpha-induced apoptosis. These findings suggest that HCV infection may cause anti-apoptosis by activation of NF-kappaB and implicate a mechanism by which HCV may evade the host's immune surveillance leading to viral persistence and possibly to hepatocarcinogenesis.

Adult↗

PubMed1999

Stress, social relations, and old age mortality in Taiwan.

The research analyzed the relationships among stress, social relations, and mortality in a probability sample of 4,049 Taiwanese adults, aged 60 and over. The baseline survey was conducted in 1989 and the survival status of the respondents was ascertained during the subsequent 4 years. Death of a spouse or a child was found to increase the risk of dying directly and indirectly, whereas major financial difficulty during the past 5 years and current financial strain influenced mortality indirectly through their effects on self-rated health disability. In addition to their direct effect on mortality, martial status and work status lowered the probability of dying through decreased disability and subjective ill health. Finally, no buffering effects of social support were substantiated.

Adaptation, Psychological↗

PubMed1998

The effect of education on mortality among older Taiwanese and its pathways.

The present research examines the impact of education on the mortality of older Taiwanese during a 4-year interval from April 1989 to April 1993. Data used for this study come from the Taiwan Survey of Health & Living Status of the Elderly (1989). The research decomposes the effect of education into the direct effect and the indirect effects by means of health status, health behaviors, and social relationships. We have shown that, of the total effect of educational attainment on the mortality of older Taiwanese, about 83% represents indirect influences by means of the 3 mediating factors, particularly health status. On the other hand, the magnitude of the direct effect, which might reflect influences of additional intervening variables on old-age mortality, is low and not statistically significant. The results demonstrate that the apparent strong effect of education on mortality among older Taiwanese can be accounted for parsimoniously through 3 major pathways.

Aged↗

PubMed1998

Educational attainment and transitions in functional status among older Taiwanese.

Despite considerable research examining the influence of socioeconomic status on health, few studies have considered this relationship as it pertains to older adults in non-Western societies. We attempt to ascertain the influence of education on changes in physical functioning in a rapidly developing country. Data come from the 1989 Survey of Health and Living Status of the Elderly in Taiwan and a follow-up interview in 1993 (N = 4,049, age = 60+). Individuals are conceptualized to be in a state of functional independence or functional limitation at the time of origin, based on their ability to perform three physical functioning tasks. The outcome at the follow-up interview is categorized as functionally independent, limited, or dead, allowing for six probabilities, one from each state of origin to each outcome. These are calculated using a multinomial logit model, controlling for other factors often thought to be associated with health transitions. High levels of educational attainment result in a decreased incidence of functional limitation for those originating in a state of independence. Contrary to expectations, however, education has little influence on those who originate functionally limited. Thus, higher education plays a substantial role in primary prevention of morbidity, delaying the onset of disability, but other factors are more important once limitations begin. We speculate on the reasons behind these findings, including that the results may be culturally dependent.

Activities of Daily Living↗

PubMedDate not supplied

Sex, marital status, and psychological distress in later life: a comparative analysis.

Some investigators maintain that while married men experience less distress than married women, the opposite may be true for those who are not married. In this instance, women are thought to report fewer symptoms of distress than men. The purpose of this study is to examine the relationships among gender, marital status, psychological distress and alcohol use in five culturally-diverse groups of older adults: U.S. whites, U.S. blacks, Japanese, Taiwanese and elderly people in the People's Republic of China. We find little evidence of the pattern described above. Instead, the data suggest that being single is equally detrimental for older men and women regardless of the cultural setting.

Journal Article↗