Original Article

Hu ZH, Chen SZ, Jin Y, Xiong Y, Wang W, Ma XJ, Song M
Correspondence: Prof Chen Shao-zong, cszong@fmmu.edu.cn

ABSTRACT
Introduction In order to find a suitable carrier to deliver the product of gene transfection to improve the performance of bioengineered dermis, we used microencapsulation and gene transfection technology together for the first time and found that it was feasible.
Methods We used a recombinant nerve growth factor (pcDNA3.1+/NGF) to modify NIH3T3 cells genetically. Control of NIH3T3-NGF cells were encapsulated within microspheres composed of alginate-poly-L-lysine-alginate and cultivated in-vitro. The concentration of NGF released from the microencapsulated NIH3T3-NGF cells was confirmed using ELISA assay. We co-cultivated microencapsulated NIH3T3-NGF cells, NIH3T3 cells (control) with human keratinocytes and fibroblasts, and tested the percentage of cycle of these cells. The alkaline hydrolysis method was used to analyse the content of hydroxyproline (Hyp). Immunohistochemistry method was used to calculate the transformation efficiency from fibroblasts to myofibroblasts.
Results The concentration of NGF released from the microencapsulated NIH3T3-NGF cells lasted about six weeks in the supernatant of bioengineered dermis in-vitro. The proliferation of keratinocytes, as well as the concentration of Hyp in supernatant of fibroblasts, were promoted about three times. Transformation efficiency from fibroblasts to myofibroblasts was increased approximately two-fold because of the bio-effects of NGF. Two kinds of microencapsulations were seeded into collagen which contained human fibroblasts to form bioengineered skin. Microencapsulated NIH3T3-NGF cells formed a thicker dermis. The concentration of Hyp in the bioengineered skin which indicated the level of collagen synthesis was increased due to existing NGF.
Conclusion Microencapsulated NIH3T3-NGF cells can be used to enhance performance of bioengineered dermis and it also can be deduced that other cytokines can be used to treat local wound areas.

Keywords: dermis, gene transfection, microencapsulation, nerve growth factor, tissue engineering
Singapore Med J 2006; 47(6): 504-511

Ho TF, Tai BC, Lee EL, Cheng S, Liow PH
Correspondence: Dr Ho Ting Fei, phshotf@nus.edu.sg

ABSTRACT
Introduction The objective of this study was to assess the prevalence of young females at risk of developing eating disorders (ED) and the associated socio-demographical variables.
Methods A set of self-administered questionnaires consisting of an Eating Attitude Test (EAT), an Eating Disorder Inventory (EDI) and a socio-demographical questionnaire was administered to 4,461 young females. Based on scores for EAT and/or EDI-drive for thinness (EDI-DT) subscale, subjects were categorised into either "normal" (NM) or "at risk" (AR) of ED.
Results Mean age of the subjects was 16.7 years (range 12-26 years). The ethnic composition was 78.8 percent Chinese, 11.7 percent Malay, 6.6 percent Indian and 3 percent other ethnic groups. Prevalence of AR was 7.4 percent (95 percent confidence interval [CI] 6.7-8.2 percent). Mean EAT and EDI-DT scores for AR were significantly higher than that of NM (EAT: mean difference is 22.1, 95 percent CI 20.7-23.4, p-value is less than 0.0001; EDI-DT: mean difference is 10.9, 95 percent CI 10.5-11.4, p-value is less than 0.0001). Female Malays constituted a significantly larger proportion of AR (20.6 percent) as compared to NM (10.9 percent). AR females are more likely to use Malay as a spoken language at home (prevalence rate ratio 1.70, p-value is 0.001) and to be better educated with completion of General Certificate of Education (GCE) "O" levels. However, the parents of AR females are likely to be less well educated (below GCE "A" levels).
Conclusion The prevalence of females at risk of developing ED is 7.4 percent. Malay ethnic group, using Malay language at home and the educational levels of both the subjects and their parents appear to be associated with an increased risk for development of ED.

Keywords: anorexia nervosa, bulimia nervosa, eating attitude test, eating disorders, socio-demographical variables
Singapore Med J 2006; 47(6): 499-503

Zalilah MS, Khor GL, Mirnalini K, Norimah AK, Ang M
Correspondence: Dr Zalilah Mohd Shariff, zalilah@medic.upm.edu.my

ABSTRACT
Introduction Paediatric obesity is a public health concern worldwide as it can track into adulthood and increase the risk of adult morbidity and mortality. While the aetiology of obesity is multi-factorial, the roles of diet and physical activity are controversial. Thus, the purpose of this study was to report on the differences in energy intake, diet composition, time spent doing physical activity and energy expenditure among underweight (UW), normal weight (NW) and at-risk of overweight (OW) Malaysian adolescents (317 females and 301 males) aged 11-15 years.
Methods This was a cross-sectional study with 6,555 adolescents measured for weights and heights for body mass index (BMI) categorisation. A total of 618 subjects were randomly selected from each BMI category according to gender. The subjects' dietary intake and physical activity were assessed using self-reported three-day food and activity records, respectively. Dietary intake components included total energy and macronutrient intakes. Energy expenditure was calculated as a sum of energy expended for basal metabolic rate and physical activity. Time spent (in minutes) in low, medium and high intensity activities was also calculated.
Results The OW adolescents had the highest crude energy intake and energy expenditure. However, after adjusting for body weight, the OW subjects had the lowest energy intake and energy expenditure (p-value is less than 0.001). The study groups did not differ significantly in time spent for low, medium and high intensity activities. Macronutrient intakes differed significantly only among the girls where the OW group had the highest intakes compared to UW and NW groups (p-value is less than 0.05). All study groups had greater than 30 percent and less than 55 percent of energy intake from fat and carbohydrate, respectively.
Conclusion The data suggested that a combination of low energy expenditure adjusted for body weight and high dietary fat intake may be associated with overweight and obesity among adolescents. To prevent overweight and obesity among children and adolescents, strategies that address eating behaviours and physical activity are required. Various segments of the society must be involved in efforts to promote healthful dietary intakes and active lifestyle in children and adolescents.

Keywords: adolescents, dietary intake, energy expenditure, energy intake, obesity, physical activity
Singapore Med J 2006; 47(6): 491-498

Ng CJ, Kamal SF
Correspondence: Dr Chirk-Jenn Ng, ngcj@um.edu.my

ABSTRACT
Introduction This study aimed to qualitatively explore adolescents' sexuality and their relation to human immunodeficiency virus (HIV) risk in Malaysia.
Methods This study was conducted in 2002 among 16 male and female private college students aged between 18 and 22 years old, all of whom were sexually active. Semi-structured individual interviews were carried out.
Results There were definite differences in gender roles in terms of how adolescents perceived sex, selection of sex partners and communication with their partners. Definitions of stable and casual relationships differed between males and females. Most participants were concerned about pregnancy rather than sexually transmitted diseases or HIV infection when they interpreted safe sex. Reasons for not practising safe sex include trust between sex partners, complacency, low perception of risk, and negative attitudes towards condom use.
Conclusion These findings were closer to those observed in the developed countries. The findings from this study will serve as a guide to plan for local adolescent health education. It can also serve as a basis for more in-depth quantitative and qualitative research on adolescent sexuality.

Keywords: adolescent sexuality, human immunodeficiency virus, qualitative research, sex education, sexuality
Singapore Med J 2006; 47(6): 482-490

Lee LK, Chen PCY, Lee KK, Kaur J
Correspondence: Dr Lee Lai Kah, laikah_lee@imu.edu.my

ABSTRACT
Introduction Sexual intercourse among Malaysian adolescents is a major concern, especially with the worry of HIV/AIDS. This study was done to determine the prevalence of sexual intercourse among secondary school students aged 12 to 19 years in Negeri Sembilan, Malaysia.
Methods This is a cross-sectional school survey conducted on 4,500 adolescent students based on a structured questionnaire. Data were collected using the self-administered questionnaire (translated version of the Youth Risk Behaviour Surveillance in Bahasa Malaysia).
Results The study showed that 5.4 percent of the total sample were reported to have had sexual intercourse. The proportion among male students who had had sex was higher (8.3 percent) compared with female students (2.9 percent). The mean age at first sexual intercourse was 15 years. One percent of students reported that they had been pregnant or had made someone else pregnant. Adolescent sexual intercourse was significantly associated with (1) socio-demographical factors (age, gender); (2) environmental factors (staying with parents); and (3) substance use (alcohol use, cigarette smoking, drug use), even after adjustment for demographical factors. The survey showed that 20.8 percent of respondents had taken alcohol, 14.0 percent had smoked cigarettes, 2.5 percent had tried marijuana, 1.2 percent had tried ecstasy pills, 2.6 percent had tried glue sniffing, 0.7 percent had tried heroin, and 0.7 percent had intravenous drugs.
Conclusion Prevalence of sexual intercourse among Malaysian adolescents was relatively low compared to developed countries. However, certain groups of adolescents tend to be at higher risk of engaging in sexual intercourse. This problem should be addressed early by targeting these groups of high-risk adolescents.

Keywords: adolescents, premarital sex behaviour, sexual intercourse, substance abuse
Singapore Med J 2006; 47(6): 476-481

Lye DCB, Nguyen DH, Giriputro S, Anekthananon T, Eraksoy H, Tambyah PA
Correspondence: Dr Paul Ananth Tambyah, mdcpat@nus.edu.sg

ABSTRACT
There has been much alarm about avian influenza and its potential for a global pandemic ever since the current epidemic of avian influenza infections in humans began in 2003. While there have been a number of published reports on the clinical features of avian influenza, there are few guidelines on the practical management of patients with avian influenza. A symposium organised by the Society of Infectious Disease (Singapore), Society of Intensive Care Medicine and the Singapore General Hospital was held in Singapore to gather the views of experts from Turkey, Thailand, Vietnam and Indonesia who collectively had first-hand experience of the management of the majority (more than 100 of 192) of cases of avian influenza worldwide. The experts emphasised the importance of adapting international guidelines to the practicalities of situations on the ground. There was stress on wide screening using clinical criteria primarily, molecular diagnostic techniques (with reference laboratory confirmation) for diagnosis, and rational use of antiviral prophylaxis as well as infection control using at least surgical masks, gowns and gloves. A detailed analysis of data from a pooled database from these and other affected countries is critical to building up the evidence base for practical internationally applicable guidelines.

Keywords: avian influenza, infection control, infectious disease, influenza, viral infection
Singapore Med J 2006; 47(6): 471-475

Ziaee V, Razaei M, Ahmadinejad Z, Shaikh H, Yousefi R, Yarmohammadi L, Bozorgi F, Behjati MJ
Correspondence: Dr Vahid Ziaee, ziaee@tums.ac.ir

ABSTRACT
Introduction Ramadan is the holiest month in the Islamic calendar and Muslims fast during this month. We designed this study to evaluate the effect of Ramadan fasting on plasma lipids and lipoproteins.
Methods This cohort study was performed during Ramadan in December 2002 (Islamic year 1423). The subjects were 81 students of Tehran University of Medical Sciences. We evaluated weight, body mass index (BMI), glucose, triglyceride (TG), cholesterol, low density lipoprotein (LDL), high density lipoprotein (HDL), and very low density lipoprotein (VLDL), before and after Ramadan.
Results Body weight and BMI both decreased during Ramadan fasting in both genders. Glucose and HDL decreased and LDL increased significantly during fasting in Ramadan, but there was no significant change in total cholesterol, TG and VLDL. We did not find any association between TG, cholesterol, LDL, VLDL, HDL and the following variables: sex, body weight changes, and two or three instances of meals before Ramadan. Triglyceride level also increased in students with normal BMI while it decreased in overweight subjects.
Conclusion This study indicated that Ramadan fasting led to a decrease in glucose and weight. Although there was a significant reduction in meal frequency, a significant increase in LDL and decrease in HDL was noted during Ramadan. It seems that the effect of Ramadan fasting on serum lipid levels may be closely related to the nutritional diet or biochemical response to starvation.

Keywords: cholesterol, fasting, high density lipoprotein, low density lipoprotein, Ramadan
Singapore Med J 2006; 47(5): 409-414

Bener A, Hamad A, Fares A, Al-Sayed HM, Al-Suwaidi J
Correspondence: Professor Abdulbari Bener, abener@hmc.org.qa

ABSTRACT
Introduction Over one billion Muslims fast worldwide during the month of Ramadan. Fasting during Ramadan is a radical change in lifestyle for the period of a lunar month. The objective of this study was to investigate whether Ramadan fasting has any effect on the incidence of stroke and its outcome in a geographically-defined population.
Methods We retrospectively reviewed a 13-year stroke database and studied the data on Muslim patients who were hospitalised with stroke over a 13-year period from January 1991 to December 2003. Patients were divided according to the time of presentation in relation to the month of Ramadan, one month before, during, and one month after Ramadan. The number of hospitalisations for stroke in various time periods was analysed. The age of presentation, gender, cardiovascular risk factor profiles (smoking status, hypertension, hypercholesterolaemia, diabetes mellitus, and pre-existing cardiovascular disease) were analysed. We also studied the trends of in-hospital mortality, morbidity and acute medical care provided.
Results Overall, 335 Muslim patients were hospitalised for stroke. Their mean age and standard deviation were 56.99 and 13.9 years, respectively. The number of hospitalisations for stroke was not significantly different in the month of Ramadan (29 cases), when compared to the month before Ramadan (30 cases) and the month after Ramadan (29 cases). Risk factors included for stroke were not significantly different in Ramadan when compared to the month before and after Ramadan. These associated diseases were hypertension, diabetes mellitus, hypercholesterolaemia, acute myocardial infarction, and congestive heart failure.
Conclusion This study demonstrated that no significant difference was found in the number of hospitalisations for stroke while fasting during the month of Ramadan when compared to the non-fasting months.

Keywords: cerebrovascular accident, fasting, Ramadan fasting, stroke
Singapore Med J 2006; 47(5): 404-408

Halim AG, Hamidon BB, Cheong SK, Raymond AA
Correspondence: Dr Abdul Halim bin  Abdul Gafor, halimgafor@gmail.com

ABSTRACT
Introduction There is no biological marker that can accurately predict the prognosis after an acute ischaemic stroke. The main objective of this study was to evaluate the prognostic value of tissue factor (thromboplastin) levels in first ischaemic stroke.
Methods This was a prospective study of all patients with first ischaemic stroke conducted from October 2003 to February 2004. Plasma for tissue factor levels was kept at -80 degrees Celsius and was analysed at the end of the study period by an independent person. The activities of daily living (ADL) were assessed by using the Barthel index (BI) on admission and at one month after the stroke onset. Any death or recurrent events were recorded.
Results 50 patients were recruited into the study. The median tissue factor level was 184.5 +/- 97.3 pg/ml. Only age (p-value is 0.027) and middle cerebral artery (MCA) infarcts (p-value is 0.038) were found to be significant independent predictors for severe disability at one month with BI equal to or less than 9. There was no correlation of tissue factor level with BI at one month post-stroke (r equals -0.028, p-value is 0.846) and there was also no significant relationship between levels of tissue factor and recurrent events (p-value is 0.41).
Conclusion There is no correlation between tissue factor levels with acute ischaemic stroke outcome.

Keywords: brain infarction, middle cerebral artery infarction, stroke, tissue factors, thromboplastin
Singapore Med J 2006; 47(5): 400-403

NorAdina AT, Hamidon BB, Roslan H, Raymond AA
Correspondence: Dr Nor Adina Ahmad Tajudin, noradinatajudin2000@yahoo.com

ABSTRACT
Introduction There are several studies that reported a higher frequency of sleep-disordered breathing (SDB) among ischaemic stroke patients with increasing evidence linking SDB and cardiovascular complications. Many showed prevalence between 43 percent and 72 percent, taking the apnoea-hypopnoea index (AHI) equal to or greater than ten. The main objective of this study was to determine the frequency of SDB in recent ischaemic stroke patients admitted to Hospital Universiti Kebangsaan Malaysia (HUKM) and the relationship between SDB and known risk factors of ischaemic stroke.
Methods This was a cross-sectional, prospective study involving 28 consecutive acute ischaemic stroke patients admitted to HUKM over three months. Sleep studies were done within one to four weeks after stroke onset. Demographical data and associated risk factors were recorded and data were analysed.
Results There were 20 men and eight women, with mean age of 60.3 +/- 8.9 years. There were eight Malay, 16 Chinese and four Indian patients. The prevalence of SDB in ischaemic stroke depending on the AHI cut-off was: 92.8 percent for AHI greater than or equal to five, 78.5 percent for AHI greater than or equal to ten, 44.5 percent for AHI greater than or equal to 15, and 37.7 percent for AHI greater than or equal to 20. We discovered that diabetes mellitus and smoking history were important factors predicting significant SDB (AHI greater than or equal to 15) in recent ischaemic stroke cases.
Conclusion There was a high prevalence of SDB in recent ischaemic stroke patients in HUKM, comparable to other studies. Diabetes mellitus and smoking history were strong predictors of the occurrence of SDB after an ischaemic stroke.

Keywords: cerebrovascular accident, ischaemic stroke, polysomnography, sleep apnoea, sleep-disordered breathing, stroke
Singapore Med J 2006; 47(5): 392-399