Munn Sann Lye

Histomorphometric profile of the corneal response to short-term reverse-geometry orthokeratology lens wear in primate corneas: a pilot study.

Purpose: To investigate the histological changes in primate cornea induced by short-term overnight orthokeratology (OK). Methods: Nine young adult primates were used. One animal served as negative control. The remaining 8 animals wore reverse-geometry OK lenses for periods of 4, 8, 16, and 24 hours on 1 eye with the other eye as control. Central and midperipheral corneal thickness, as well as ultrastructural changes in corneal epithelium, stroma and endothelium in response to OK lenses, were evaluated. Results: OK significantly reduced the thickness of the central cornea in all treatment groups. The central corneal thinning was both stromal and epithelial in origin. Substantial midperipheral corneal thickening was seen in 16-hour and 24-hour lens-wear groups and this effect was both stromal and epithelial in origin as well. Histology evidence indicated the primary epithelial response in the central cornea was compression of cells that resulted in wing cells becoming shorter and basal cells being squatted rather than lost or migration of cell layers. These pronounced cell shape changes occurred without compromising the structural integrity of the desmosomes. The thickened corneal epithelium has normal cell layers. The squamous cells have larger surface sizes and are composed of oval instead of flattened nuclei. This implied delayed surface cell exfoliation at the thickened midperipheral epithelium. Physical presence of OK lens over the cornea did not influence the microstructures of microvilli and microplicae, endothelium, and collagen distribution. Conclusions: The primate cornea, particularly the corneal epithelium, responds rapidly to the application of reverse-geometry OK lenses with significant epithelial cell shape alterations with short-term OK lens wear. This finding suggests that the corneal epithelium is moldable in response to the physical forces generated by the OK lenses.

The heritability of premenstrual syndrome

We aimed to determine (1) the prevalence of premenstrual syndrome in a sample of twins and (2) the relative contribution of genes and environment in premenstrual syndrome. A group of 193 subjects inclusive of same gender twins (n = 176) and females from opposite sex twin sets (n = 17) entered the study. Heritability analysis used same gender twin data only. The probandwise concordance rate for the presence or absence of premenstrual syndrome was calculated and the heritability of premenstrual syndrome was assessed by a quantitative genetic model fitting approach using MX software. The prevalence of premenstrual syndrome was 43.0% and 46.8% in monozygotic and dizygotic twins, respectively. The probandwise concordance for premenstrual syndrome was higher in monozygotic (0.81) than in dizygotic twins (0.67), indicating a strong genetic effect. Quantitative genetic modeling found that a model comprising of additive genetic (A) and unique environment (E) factors provided the best fit (A: 95%, E: 5%). No association was found between premenstrual symptom and the following variables: belonging to the opposite gender twin set, birth weight, being breast fed and vaccination. These results established a clear genetic influence in premenstrual syndrome.

Time series modelon hand, foot and mouth disease in Sarawak, Malaysia

Abstract Objective To model and forecast hand, foot and mouth disease (HFMD) cases since there has not been any studies on time series modelling of HFMD in Sarawak, Malaysia. Methods The longitudinal data of HFMD collected over the past 7 years (2006-2012) showed a cyclical pattern of outbreak every 2 to 3 years. The data consisted of weekly number of HFMD reported cases from 2006 to 2012. An auto regressive moving average (ARMA) model was fitted to the data. Batting average was used to measure the performance of our forecast for 2013. Results The results indicate that ARMA model fit the trends of HFMD in Sarawak very close to the actual data during our study period. Our prediction for the number of HFMD reported cases lies within the 90% interval range for the first 16 weeks in 2013. Conclusions An ARMA(1,4) model fits the data well and has good prediction ability of over 90% accuracy.

Perspective of postpartum depression theories: a narrative literature review

Postpartum depression is the most prevalent emotional problem during a women′s lifespan. Untreated postpartum depression may lead to several consequences such as child, infant, fetal, and maternal effects. The main purpose of this article is to briefly describe different theoretical perspectives of postpartum depression. A literature search was conducted in Psych Info, PubMed, and Science Direct between 1950 and 2015. Additional articles and book chapters were referenced from these sources. Different theories were suggested for developing postpartum depression. Three theories, namely, biological, psychosocial, and evolutionary were discussed. One theory or combinations of psychosocial, biological, and evolutionary theories were considered for postpartum depression. The most important factor that makes clinicians′ choice of intervention is their theoretical perspectives. Healthcare providers and physicians should help women to make informed choices regarding their treatment based on related theories.

CYP1A1 MspI Polymorphism and Cervical Carcinoma Risk in the Multi-Ethnic Population of Malaysia: a Case-Control Study

BACKGROUND Tobacco smoking is considered a risk factor for cervical cancer development due to the presence of tobacco based carcinogenic metabolites in cervical cells of female smokers. In this study, we investigated the role of the T3801C (MspI) polymorphism of CYP1A1, a gene encoding an enzyme necessary for the initiation of tobacco based carcinogen metabolism, on cervical cancer risk. The T to C substitution may alter CYP1A1 activities, potentially elevating cervical cancer risk. Since results of gene-disease association studies vary according to the study population, the multi-ethnic population of Malaysia provides an excellent representative cohort for identifying and comparing the cervical cancer risk among the 3 major ethnics in Southeast Asia in relation to CYP1A1 MspI polymorphism. MATERIALS AND METHODS A total of 195 Thin Prep Pap smear samples from HPV negative and cancer free females were randomly selected as controls while 106 formalin fixed paraffin embedded samples from females with invasive cervical cancer were randomly selected for the cases group. The polymorphisms were identified using restriction fragment length polymorphism (RFLP) PCR. RESULTS We found no significant associations between CYP1A1 MspI polymorphism and cervical cancer in the general Malaysian female population. However, upon ethnic stratification, the variant C/C genotype was significantly associated with a 4.66-fold increase in cervical cancer risk in Malay females (95% CI= 1.21-17.9; p=0.03). No significant association was observed in the Chinese and Indian females. Additionally, there were no significant associations in the dominant model and allele frequency model analysis in both the general and ethnically stratified female population of Malaysia. CONCLUSIONS Our findings suggest that the C/C genotype of CYP1A1 MspI polymorphism is associated with the development of cervical carcinoma in the Malay females of Malaysia.

Relationships among perceived quality of healthcare services, satisfaction and behavioural intentions of international students in Kuala Lumpur, Malaysia: a cross-sectional study

Objective The current study aimed to investigate the relationships among the perceived quality of healthcare services, satisfaction and behavioural intentions among international students in Kuala Lumpur, Malaysia. Setting A cross-sectional study on public universities in Kuala Lumpur, Malaysia. Participants All participants in this study were international students joining public universities in Kuala Lumpur, Malaysia. Primary independent variable Perceived quality of healthcare services measured on a SERVQUAL scale. Primary dependent variable Participants’ satisfaction of healthcare services assessed using five items. Secondary dependent variable Behavioural intentions measured on six items. Results Of the 556 international students, 500 (90%) completed the survey. The study used structural equation modelling (SEM) through the AMOS (Analysis of Moment Structures) software to analyse the data. SEM analyses showed that the perceived quality of healthcare services significantly and directly affected satisfaction, with a value of 89% and an effect size of 0.78. It also had a significant indirect impact on the behavioural intentions (0.78) of international students. The results indicated that participants’ satisfaction had a statistically significant impact on their behavioural intentions (0.77). Conclusion Perceived quality of care is an important driver of international students’ satisfaction and their behavioural intention with healthcare services. Such relations of effects among the three investigated factors were also positive and significant.

Association Between Preconception Care and Birth Outcomes

Purpose: To evaluate the association between preconception care and the risk of adverse birth outcomes. Design: A quasi-experimental study comparing 2 groups: (1) integrated maternal health care (MHC) program (with preconception care) and (2) standard MHC program (without preconception care). Setting: Maternal health-care clinics in Alvand and Qazvin cities in Qazvin Province, Iran. Participants: A total of 152 and 247 Iranian women aged 16 to 35 years were enrolled in the integrated MHC and standard MHC program, respectively. Measures: The birth outcomes measured included low birth weight, preterm birth, maternal and neonatal complications, and mode of delivery (normal vaginal delivery and cesarean delivery). Analysis: Multiple logistic regression was performed to determine the impact of preconception care and risk of adverse birth outcomes with adjusted odds ratios (ORs) as effect sizes. Results: One hundred forty-seven women in integrated MHC and 218 women in standard MHC completed this study. Preconception care was associated with reduced risk of preterm birth (OR = 0.298; 95% confidence interval [CI] = 0.120-0.743; P = .009), low birth weight (OR = 0.406; 95% CI = 0.169-0.971; P = .043), maternal complication (OR = 0.399; 95% CI = 0.241-0.663; P < .001), and neonatal complications (OR = 0.460; 95% CI = 0.275-0.771; P = .003). Conclusion: The findings of the present study revealed advantages of preconception care with reduced adverse birth outcomes.