Biomedical subjects

A Seow

Publications and source records attributed to A Seow.

45 records · Page 3Linked to original sources

PubMed1996

Biomarkers: a molecular approach to cancer epidemiology.

The rapidly evolving field of molecular epidemiology represents a paradigm shift in medical research, illustrating the convergence of basic, clinical and epidemiologic research, as well as the application of laboratory methods to population studies. As a complement and improvement to traditional epidemiologic approaches, the use of biomarkers offers more accurate exposure assessment at an individual level, better understanding of the biological mechanism of carcinogenesis by tracking a continuum of events between exposure and disease, as well as the ability to discern host or genetic factors that may account for variations in cancer susceptibility among individuals or ethnic populations. Further, biomarkers have also proved useful in cancer diagnosis and prognosis. This article attempts to review the latest progress in molecular cancer epidemiology and to summarise the current state of research in Singapore.

Biomarkers, Tumor↗

PubMed1996

Molecular epidemiology: issues in study design and statistical analysis.

Traditional analytical epidemiology is directed at identifying the association between risk factors and occurrence of disease by using crude exposure data derived from questionnaires or clinical measures, and taking clinical disease as the end point. With the rapid development in molecular biology and laboratory methods, it is now possible to use biomarkers which are capable of identifying molecular events for epidemiologic research. This improved sensitivity enables us to develop a mechanistic understanding of disease causation: a step closer to the unravelling of the "black box" of traditional epidemiology. Biomarkers may be classified as internal indicators of exposure (biomarkers of exposure), indicators of preclinical adverse effect (biomarkers of effect) or indicators of an intrinsic or acquired susceptibility to disease (biomarkers of susceptibility). Biomarkers provide a better definition of exposure and disease status and consequently they could help to reduce misclassification bias in both exposure and disease, reduce the follow-up time in prospective studies, as well as identify possible interactions between risk factors on disease occurrence. However, a biomarker needs to be validated and its distribution in large populations described before it can be used profitably for aetiologic research. Also, the use of biomarkers in epidemiologic research raises other interesting epidemiological and statistical issues like confounding, effect modification and the analysis of repeated measurements. Molecular epidemiology is a multidisciplinary endeavour which comprises molecular biology, epidemiology and biostatistics. Clearly then, to carry out research in this field profitably, the molecular biologist, epidemiologist and biostatistician must acquire not only expertise in their respective fields, but also an integrated understanding of all three fields. The molecular biologist is not merely a laboratory bench worker; the epidemiologist, a field data-collector and the biostatistician, a number cruncher. They must work together to pry open the "black box" to gain a greater insight into how risk factors operate to initiate disease onset and ultimately to make use of this knowledge base to implement preventive measures.

Biomarkers↗

PubMed1995

Beliefs and attitudes as determinants of cervical cancer screening: a community-based study in Singapore.

BACKGROUND: The investigation of cervical cancer screening acceptance in relation to health beliefs and attitudes presents a challenge in a multiethnic population such as Singapore's, where the uptake is currently suboptimal in high-risk groups. This study attempts to identify cognitive barriers to screening activity in order to suggest possible directions for cervical cancer prevention efforts. METHODS: A cross-sectional survey consisting of a household interview of 640 randomly selected women ages 21-65 years was performed. The screening history and future intention to have a Pap smear were elicited, and attitudes toward cancer and the Pap smear as expressed in 14 statements were measured on a five-point scale. RESULTS: Of the respondents, 73.1% were aware of the Pap smear, and about half (49.7%) had obtained the information from a doctor or nurse. Overall, the belief in personal susceptibility to cancer was low (58.9%) and a substantial proportion (48.7%) of women were of the attitude that cancer could not be prevented. The effect on a future intention to have a smear varied between women who had had and women who had not had a smear. Among the former, perceived barriers such as discomfort and embarrassment had a significant influence, while a belief in personal susceptibility was an important determinant for the latter group. CONCLUSIONS: The means of increasing the acceptance of the Pap smear, both for the first time and subsequently, are culture-specific and must address the appropriate health beliefs and attitudes. In Singapore, such efforts should include not only influencing awareness and perceptions through public education but also reducing barriers by creating an appropriate environment for the delivery of this important health service.

Adult↗

PubMed1994

From colony to city state: changes in health needs in Singapore from 1950 to 1990.

The disease patterns and health needs of Singaporeans have altered dramatically over the last half-century as a result of both economic progress and socio-demographic change. This is reflected by improvements in the universal indices of health status such as the infant mortality rate and life expectancy at birth. At the same time, chronic degenerative diseases such as cancer and heart disease have replaced infectious diseases as the major causes of death, as is the pattern in industrialized countries throughout the world. The challenge for public health in Singapore today is to find cost-effective means to control these diseases, and in this regard, the country has embarked on a strategy of disease prevention and health promotion for the next decade, aimed at reducing the levels of major lifestyle-related risk factors by providing a supportive environment for behavioural change.

Adult↗

PubMed1994

Prevalence and determinants of cervical cancer screening: a community-based study in Singapore.

A cross-sectional survey of 568 married women aged 21-65 years in the Pasir Panjang Constituency was conducted to determine the prevalence of cervical cancer screening in the community and the factors affecting acceptance of this screening test. Results show that 309 (54.4%) of the respondents had ever had a Pap smear. The women who reported having had a smear were more likely to be below 45 years of age (prevalence ratio 1.47, 95% confidence interval 1.15 to 1.88), Chinese and of a higher socioeconomic status (1.68, 1.33 to 2.12). They were also more likely to have married at a later age (1.68, 1.21 to 2.31) than women who had not had a smear. Age and socioeconomic status remained independent predictors on multivariate analysis. The findings suggest that an important task of public health practitioners is to increase the uptake of screening among older and socially disadvantaged women who are known to be at the highest risk of cervical cancer. In addition, strategies to encourage younger women to continue regular attendance at screening clinics beyond their childbearing years will be important for the future.

Adult↗

PubMed1994

The role of scintigraphy in the evaluation of fever of unknown origin.

Nuclear medicine imaging techniques are an important adjunct to other currently used modalities in the evaluation of patients with fever of unknown origin. Bone scanning performed with technetium-labeled phosphonate agents may identify osteomyelitis when plain radiography fails and may disclose sites of joint inflammation or unsuspected osseous tumor metastasis. Indium-labeled autologous leukocytes localize at sites of inflammation in the same manner as unlabeled leukocytes. Gallium citrate accumulates in areas of inflammation and in some tumors, most notably lymphomas. In most cases, scintigraphy is best used to determine the location of a lesion rather than to specifically identify the pathologic process.

AIDS-Related Opportunistic Infections↗

PubMed1993

Adult onset polymyositis/dermatomyositis: clinical and laboratory features and treatment response in 75 patients.

OBJECTIVES: To determine possible similarities and differences in clinical and laboratory features and treatment response between patients in Singapore with polymyositis (PM) and dermatomyositis (DM) and reported series. METHODS: Case records of adult patients (16 years old and above) referred to the 3 main electromyographic (EMG) laboratories in Singapore between 1 June 1986 and 31 May 1991 were reviewed if the referring diagnosis was myositis or myopathy for investigation. A computer search for adult patients with a diagnosis of PM/DM (ICD codes 710.3, 710.4, 517.8) who attended the main rheumatology and neurology centre during this period was also carried out. The criteria for PM/DM proposed by Bohan and Peter was adopted. RESULTS: The incidence of PM/DM was 7.7 cases per million population per year. There were 35 PM and 40 DM cases with a median age at diagnosis of 50.7 years (SD: 16.7) and significantly more females in the PM group (p < 0.05). At presentation, 86.7% had proximal myopathy, 34.7% had arthralgia/arthritis and 18.7% had cutaneous vasculitis. The creatine kinase level was elevated in 89.3% of patients and positive EMG and muscle biopsy in 79.4% and 76.4% respectively. Systemic lupus erythematosus was the commonest associated connective tissue disease. The percentage of patients with malignancy was higher in DM compared with PM (p < 0.01) and they were significantly older (mean age 61.8 years) (p < 0.001). Patients who achieved remission were significantly younger (mean age 46.4 years, p < 0.05). The overall mortality rate was 26.7% with infection and malignancy as the main causes of death. CONCLUSION: The results of the study suggest ethnicity does not influence the expression of PM/DM in view of the considerable similarities in frequency and clinical expression of disease in the population studied compared with series from other countries.

Adult↗

PubMed1992

Cervical cancer: trends in incidence and mortality in Singapore 1968 to 1987.

Analysis of data collected by the population-based Singapore Cancer Registry reveals that the age-standardised incidence of cervical cancer has decreased from 18.2 per 100,000 females in 1968-72 to 16.2 per 100,000 in 1983-87, and its ranking among the most common female cancers has fallen from second to fourth place behind cancers of the breast, colon/rectum and lung. Mortality from the disease has also shown a corresponding fall from 7.3 per 100,000 to 5.5 per 100,000 women over the same period. Cervical cancer incidence rates are in general highest among Indian women, intermediate in Chinese and lowest in Malays. Age-specific incidence curves over time show a marked fall in rates in women over 50 years of age, whereas younger women (35-44 years old) show a small increase. A similar increase in rates has been observed in various other countries. Internationally, Singapore's incidence rate falls between the highs of South America and parts of Asia, and the lower rates of North America and Europe. The decrease in rates is comparable with the overall global trend, but falls short of that achieved by countries with systematic cytological screening programmes.

Adult↗

PubMed1990

Awareness and acceptance of hepatitis B vaccination in Clementi, Singapore.

Hepatitis B Virus infection, a public health problem in Singapore, can be effectively controlled by vaccination. This paper reports on a study conducted in 1988/89 to ascertain the awareness and uptake rate of Hepatitis B vaccination. A list of children born between November 1986 and May 1987 in the catchmen zone of the Clementi Maternal and Child Health (MCH) Clinic was obtained. Out of a total of 257 children, 226 (87.9%) responded to our study in May 1988 which was part of a larger community health survey carried out by a group of medical students. The vaccination uptake rate was 23%. The awareness of the parents on Hepatitis B virus infection and vaccination was assessed using a standardised questionnaire. About two-thirds were aware of the main modes of Hepatitis B transmission, 46.5% were aware of the long-term consequences of Hepatitis B infection and 6.6% thought that the vaccine was not safe from serious side effects. A follow-up survey of the respondents was carried out in August 1989. The Hepatitis B vaccination uptake had increased to 48.3%. The immunisation status showed a correlation with the ethnic group, father's occupation and awareness score of respondents. The more than two-fold increase in uptake rate can be attributed to a reduction in the cost of Hepatitis B vaccination and a vigorous nation-wide education programme during the preceding year.

Asian People↗