MyMedR

Displaying publications 4781 - 4800 of 8505 in total

Abstract:

Sort:

Fulltext Recycling of superfine resolution agarose gel

Seng TY, Singh R, Faridah QZ, Tan SG, Alwee SS

Genet. Mol. Res., 2013;12(3):2360-7.
PMID: 23546970 DOI: 10.4238/2013.March.11.1

Genetic markers are now routinely used in a wide range of applications, from forensic DNA analysis to marker-assisted plant and animal breeding. The usual practice in such work is to extract the DNA, prime the markers of interest, and sift them out by electrically driving them through an appropriate matrix, usually a gel. The gels, made from polyacrylamide or agarose, are of high cost, limiting their greater applications in molecular marker work, especially in developing countries where such technology has great potential. Trials using superfine resolution (SFR) agarose for SSR marker screening showed that it is capable of resolving SSR loci and can be reused up to 14 times, thus greatly reducing the cost of each gel run. Furthermore, for certain applications, low concentrations of agarose sufficed and switching to lithium borate buffer, instead of the conventional Tris-borate-ethylenediaminetetraacetic acid buffer, will further save time and cost. The 2.5% gel was prepared following the Agarose SFR(TM) manual by adding 2.5 g agarose powder into 100 mL 1X lithium borate buffer in a 250-mL flask with rapid stirring. Two midigels (105 x 83 mm, 17 wells) or 4 minigels (50 x 83 mm, 8 wells), 4 mm thickness can be prepared from 100 mL gel solution. A total of 1680 PCR products amplified using 140 SSR markers from oil palm DNA samples were tested in this study using SFR recycled gel. As average, the gel can be recycled 8 times with good resolution, but can be recycled up to 14 times before the resolutions get blurred.
Fulltext Prevalence of depression in stroke patients with vascular dementia in universiti kebangsaan malaysia medical center

Khoo KF, Tan HJ, Rosdinom R, Raymond AA, Norlinah MI, Shamsul A, et al.

Med J Malaysia, 2013 Apr;68(2):105-10.
PMID: 23629553 MyJurnal

Depression among patients with vascular dementia is frequently overlooked and potentially causes significant morbidity. There is limited data in Malaysia on the subject and this study was conducted to determine the prevalence of depression in vascular dementia (VaD) in UKMMC.
Molecular sex identification of painted storks (Mycteria leucocephala): using FTA cards, horizontal PAGE and quick silver staining

Yee EY, Zainuddin ZZ, Ismail A, Yap CK, Tan SG

J Genet, 2013 Apr;92(1):e15-8.
PMID: 23628715
Fulltext Study protocol: the effect of vitamin D supplements on cardiometabolic risk factors among urban premenopausal women in a tropical country -- a randomized controlled trial

Ramly M, Moy FM, Pendek R, Suboh S, Tan Tong Boon A

BMC Public Health, 2013 May 01;13:416.
PMID: 23631804 DOI: 10.1186/1471-2458-13-416

BACKGROUND: Besides its classical role in musculoskeletal diseases, vitamin D deficiency has recently been found to be associated with cardiometabolic risks such as hypertension, diabetes mellitus and hypercholesterolemia. Although Malaysia is a sunshine-abundant country, recent studies found that vitamin D deficiency prevalence was significantly high. However, few published studies that measured its effect on cardiometabolic risk factors were found in Malaysia. There are also limited clinical trials carried out globally that tried to establish the causality of vitamin D and cardiometabolic risks. Therefore, a double blind, parallel, randomized controlled trial on vitamin D and cardiometabolic risks is planned to be carried out.The objective of this study is to investigate whether vitamin D supplements can reduce the cardiometabolic risk and improve the quality of life in urban premenopausal women with vitamin D deficiency.
METHODS/DESIGN: Three hundred and twenty premenopausal women working in a public university in Kuala Lumpur, Malaysia will be randomized to receive either vitamin D supplement (50,000 IU weekly for 8 weeks and 50,000 IU monthly for 10 months) or placebo for 12 months. At baseline, all participants are vitamin D deficient (≤ 20 ng/ml or 50 nmol/l). Both participants and researchers will be blinded. The serum vitamin D levels of all participants collected at various time points will only be analysed at the end of the trial. Outcome measures such as 25(OH) D3, HOMA-IR, blood pressure, full lipid profiles will be taken at baseline, 6 months and 12 months. Health related quality of life will be measured at baseline and 12 months. The placebo group will be given delayed treatment for six months after the trial.
DISCUSSION: This trial will be the first study investigating the effect of vitamin D supplements on both the cardiometabolic risk and quality of life among urban premenopausal women in Malaysia. Our findings will contribute to the growing body of knowledge in the role of vitamin D supplements in the primary prevention for cardiometabolic disease.
TRIAL REGISTRATION: ACTRN12612000452897.
Fulltext Palm-based diacylglycerol fat dry fractionation: effect of crystallisation temperature, cooling rate and agitation speed on physical and chemical properties of fractions

Ab Latip R, Lee YY, Tang TK, Phuah ET, Lee CM, Tan CP, et al.

PeerJ, 2013;1:e72.
PMID: 23682348 DOI: 10.7717/peerj.72

Fractionation which separates the olein (liquid) and stearin (solid) fractions of oil is used to modify the physicochemical properties of fats in order to extend its applications. Studies showed that the properties of fractionated end products can be affected by fractionation processing conditions. In the present study, dry fractionation of palm-based diacylglycerol (PDAG) was performed at different: cooling rates (0.05, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0°C/min), end-crystallisation temperatures (30, 35, 40, 45 and 50°C) and agitation speeds (30, 50, 70, 90 and 110 rpm) to determine the effect of these parameters on the properties and yield of the solid and liquid portions. To determine the physicochemical properties of olein and stearin fraction: Iodine value (IV), fatty acid composition (FAC), acylglycerol composition, slip melting point (SMP), solid fat content (SFC), thermal behaviour tests were carried out. Fractionation of PDAG fat changes the chemical composition of liquid and solid fractions. In terms of FAC, the major fatty acid in olein and stearin fractions were oleic (C18:1) and palmitic (C16:0) respectively. Acylglycerol composition showed that olein and stearin fractions is concentrated with TAG and DAG respectively. Crystallization temperature, cooling rate and agitation speed does not affect the IV, SFC, melting and cooling properties of the stearin fraction. The stearin fraction was only affected by cooling rate which changes its SMP. On the other hand, olein fraction was affected by crystallization temperature and cooling rate but not agitation speed which caused changes in IV, SMP, SFC, melting and crystallization behavior. Increase in both the crystallization temperature and cooling rate caused a reduction of IV, increment of the SFC, SMP, melting and crystallization behaviour of olein fraction and vice versa. The fractionated stearin part melted above 65°C while the olein melted at 40°C. SMP in olein fraction also reduced to a range of 26 to 44°C while SMP of stearin fractions increased to (60-62°C) compared to PDAG.
Development of solid dispersion systems of dapivirine to enhance its solubility

Gorajana A, Ying CC, Shuang Y, Fong P, Tan Z, Gupta J, et al.

Curr Drug Deliv, 2013 Jun;10(3):309-16.
PMID: 23360246

Dapivirine, formerly known as TMC 120, is a poorly-water soluble anti-HIV drug, currently being developed as a vaginal microbicide. The clinical use of this drug has been limited due to its poor solubility. The aim of this study was to design solid dispersion systems of Dapivirine to improve its solubility. Solid dispersions were prepared by solvent and fusion methods. Dapivirine release from the solid dispersion system was determined by conducting in-vitro dissolution studies. The physicochemical characteristics of the drug and its formulation were studied using Differential Scanning Calorimetry (DSC), powder X-ray Diffraction (XRD), Fourier-transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). A significant improvement in drug dissolution rate was observed with the solid dispersion systems. XRD, SEM and DSC results indicated the transformation of pure Dapivirine which exists in crystalline form into an amorphous form in selected solid dispersion formulations. FTIR and HPLC analysis confirmed the absence of drug-excipient interactions. Solid dispersion systems can be used to improve the dissolution rate of Dapivirine. This improvement could be attributed to the reduction or absence of drug crystallinity, existence of drug particles in an amorphous form and improved wettability of the drug.
Primary hyperparathyroidism: a rare cause of genu valgus in adolescence

Ratnasingam J, Tan AT, Vethakkan SR, Paramasivam SS, Ibrahim L, Lim LL, et al.

J Clin Endocrinol Metab, 2013 Mar;98(3):869-70.
PMID: 23337722 DOI: 10.1210/jc.2012-3839
Fulltext Identification of QTLs associated with callogenesis and embryogenesis in oil palm using genetic linkage maps improved with SSR markers

Ting NC, Jansen J, Nagappan J, Ishak Z, Chin CW, Tan SG, et al.

PLoS One, 2013;8(1):e53076.
PMID: 23382832 DOI: 10.1371/journal.pone.0053076

Clonal reproduction of oil palm by means of tissue culture is a very inefficient process. Tissue culturability is known to be genotype dependent with some genotypes being more amenable to tissue culture than others. In this study, genetic linkage maps enriched with simple sequence repeat (SSR) markers were developed for dura (ENL48) and pisifera (ML161), the two fruit forms of oil palm, Elaeis guineensis. The SSR markers were mapped onto earlier reported parental maps based on amplified fragment length polymorphism (AFLP) and restriction fragment length polymorphism (RFLP) markers. The new linkage map of ENL48 contains 148 markers (33 AFLPs, 38 RFLPs and 77 SSRs) in 23 linkage groups (LGs), covering a total map length of 798.0 cM. The ML161 map contains 240 markers (50 AFLPs, 71 RFLPs and 119 SSRs) in 24 LGs covering a total of 1,328.1 cM. Using the improved maps, two quantitative trait loci (QTLs) associated with tissue culturability were identified each for callusing rate and embryogenesis rate. A QTL for callogenesis was identified in LGD4b of ENL48 and explained 17.5% of the phenotypic variation. For embryogenesis rate, a QTL was detected on LGP16b in ML161 and explained 20.1% of the variation. This study is the first attempt to identify QTL associated with tissue culture amenity in oil palm which is an important step towards understanding the molecular processes underlying clonal regeneration of oil palm.
Fulltext Long term survival of patients with raised pulmonary arterial systolic pressure utilizing echocardiography-a five-year prospective study

Tan MP, Bansal SK, Wynn NN, Umerov M, Gillham A, Henderson A, et al.

J Geriatr Cardiol, 2012 Dec;9(4):328-35.
PMID: 23341836 DOI: 10.3724/SP.J.1263.2012.06191

BACKGROUND: Pulmonary arterial systolic pressure (PASP) can be estimated with transthoracic echocardiography. However, the significance of raised PASP on routine echocardiography is uncertain. In this study, we evaluated the mortality and hospitalization rates of subjects with raised PASP in a cohort of patients referred directly by their general practitioners for routine outpatient (open access) echocardiography for further analysis of suspected heart failure.
RESULTS: A total of 485 subjects were referred for open access echocardiography at our hospital in 2002. A cohort of 209/485 (43%) consecutive subjects with measurable tricuspid regurgitation were followed for a minimum of five years investigating hospitalization rates and survival. Some 62 of 209 (30%) subjects had pulmonary hypertension (PH). Subjects with PH were significantly more likely to have four or more hospital admissions (22% vs. 8%; P < 0.01) and > 30 days of cumulative hospital stay over five years (29% vs. 13%; P < 0.01). PH was significantly associated with mortality (P = 0.003), while moderate to severe PH was an independent predictor of mortality (hazard ratio: 4.31; 95% confidence interval (95% CI): 1.51-12.30). Records from the Office of National Statistics revealed that subjects with PH were more likely to have chronic lung diseases recorded as immediate or contributory causes of death (50% vs. 14%; P < 0.05).
CONCLUSIONS: PASP ≥ 36 mmHg on routine echocardiography is associated with recurrent hospital admissions, prolonged hospitalizations and increased cause of mortality. Therefore, the diagnosis of PH on echocardiography deserves further clinical evaluation, with future studies designed at defining a suitable diagnostic strategy.
KEYWORDS: Chronic lung disease; Dyspnoea; Heart failure; Pulmonary hypertension; Transthoracic echocardiography
Study site: Sunderland Royal Hospital, United Kingdom
Sun exposure and the risk of prostate cancer in the Singapore Prostate Cancer Study: a case-control study

Chia SE, Wong KY, Cheng C, Lau W, Tan PH

Asian Pac J Cancer Prev, 2012;13(7):3179-85.
PMID: 22994730

BACKGROUND: Most of the epidemiology studies on the effects of sun exposure and prostate cancer were conducted among the temperate countries of North America and Europe. Little is known about the influence on Asian populations. The purpose of current study was to evaluate any association of sun exposure with risk of prostate cancer in Chinese, Malays and Indians who reside in the tropics.
METHODS: The Singapore Prostate Cancer Study is a hospital-based case-control study of 240 prostate cancer incident cases and 268 controls conducted in Singapore between April 2007 and May 2009. Detailed information on outdoor activities in the sun, skin colour, sun sensitivity and other possible risk factors were collected in personal interviews. Cases were further classified by Gleason scores and TNM staging. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression analysis, adjusted for age, ethnicity, education, family history of any cancers, BMI and skin colour.
RESULTS: We found that prostate cancer risk was increased in subjects with black/dark-brown eyes (OR 5.88, 95%CI 3.17-10.9), darker skin colour e.g. tan/dark brown/black (OR 7.62, 95%CI 3.41-17.0), frequent sunburn in lifetime (OR 4.30, 95%CI 1.7-11.2) and increased general sun exposure in adulthood per week (OR 2.03, 95%CI 1.09-3.81). The increased risk was consistent for high grade tumours and advanced stage prostate cancers.
CONCLUSION: The findings from this study suggest that excessive sun exposure is a risk factor for prostate cancer in Asians.
Mutagenesis of the nucleocapsid protein of Nipah virus involved in capsid assembly

Ong ST, Yusoff K, Kho CL, Abdullah JO, Tan WS

J Gen Virol, 2009 Feb;90(Pt 2):392-397.
PMID: 19141448 DOI: 10.1099/vir.0.005710-0

The nucleocapsid protein of Nipah virus produced in Escherichia coli assembled into herringbone-like particles. The amino- and carboxy-termini of the N protein were shortened progressively to define the minimum contiguous sequence involved in capsid assembly. The first 29 aa residues of the N protein are dispensable for capsid formation. The 128 carboxy-terminal residues do not play a role in the assembly of the herringbone-like particles. A region with amino acid residues 30-32 plays a crucial role in the formation of the capsid particle. Deletion of any of the four conserved hydrophobic regions in the N protein impaired capsid formation. Replacement of the central conserved regions with the respective sequences from the Newcastle disease virus restored capsid formation.
Alveolar rhabdomyosarcoma of the left hand with bilateral breast metastases in an adolescent female

Tan GC, Shiran MS, Hayati AR, Sharifah NA, Nuru AS, Rohaizak M

J Chin Med Assoc, 2008 Dec;71(12):639-42.
PMID: 19114329

Rhabdomyosarcoma is a common extramammary malignancy in pediatric age groups, but it rarely metastasizes to the breast. Breast rhabdomyosarcomas are commonly metastatic, with possible primary locations at the head and neck, trunk, extremities, retroperitoneum and perianal region. We report a case of primary alveolar rhabdomyosarcoma of the upper extremities in a 17-year-old adolescent female who presented with bilateral lower limb weakness and bilateral breast lumps.
Fulltext Comparison of PCR-based genotyping methods for hepatitis B virus

Lim CK, Tan JT, Ravichandran A, Chan YC, Ton SH

Malays J Pathol, 2007 Dec;29(2):79-90.
PMID: 19108399 MyJurnal

Hepatitis B virus (HBV) is classified into eight genotypes (A to H). In this study, three genotyping methods were compared for their sensitivity and accuracy, namely PCR-RFLP on the S region, PCR-RFLP on the pre-S region and nested PCR with type specific primers. Sixty HBV samples from infected sera were genotyped. The nested PCR with type specific primers was found to be the most sensitive and produced substantial numbers of co-infections by genotypes B and C. The sensitivities for both PCR-RFLP methods were lower and did not reveal co-infections. Generally, the three methods produced consistent genotyping results in samples infected by single genotypes but for co-infections by genotypes B and C, the two PCR-RFLP methods yielded only single genotypic results. For the cases of single genotypic infections, genotypes ascertained by sequencing were in concordance across all three methods. However, when co-infections occurred, PCR analysis on clones revealed only single genotypic infections.
Fulltext A case of Hashimoto encephalopathy in a Malay woman with Graves disease

Ngiu CS, Ibrahim NM, Yahya WN, Tan HJ, Mustafa N, Basri H, et al.

BMJ Case Rep, 2009;2009.
PMID: 21709844 DOI: 10.1136/bcr.01.2009.1501

Hashimoto encephalopathy (HE) is a poorly recognised steroid-responsive encephalopathy, with prominent neuropsychiatric features. Diagnosis is often difficult due to its heterogeneous clinical presentation, especially since the thyroid status or anti-thyroid antibody titres may not be related to the disease state. Here, the case of a 23-year-old Malay woman with Graves disease who presented with progressive encephalopathy diagnosed as HE is presented. She responded dramatically to high dose intravenous and then oral corticosteroid. A month after the initiation of treatment, she regained full independency.
Fulltext Cutaneous mycobacterial spindle cell pseudotumour

Tan GC, Yap YP, Shiran MS, Sabariah AR, Pathmanathan R

BMJ Case Rep, 2009;2009.
PMID: 21686408 DOI: 10.1136/bcr.11.2008.1221

Mycobacterial spindle cell pseudotumour (MSCP) has been reported in various sites, including skin, lymph nodes, bone marrow, lung and spleen. Cutaneous lesions are extremely rare and the differential diagnoses include various spindle cell lesions. Literature review shows that this lesion has preponderance for upper limb involvement and occurs largely in immunosuppressed individuals. We report a case of MSCP of the skin due to atypical mycobacterium and discuss the risk of misdiagnosis as a sarcoma.
Localization of the antigenic sites of newcastle disease virus nucleocapsid using a panel of monoclonal antibodies

Ahmad-Raus R, Ali AM, Tan WS, Salleh HM, Eshaghi M, Yusoff K

Res Vet Sci, 2009 Feb;86(1):174-82.
PMID: 18599098 DOI: 10.1016/j.rvsc.2008.05.013

A panel of six monoclonal antibodies (mAbs) against the nucleocapsid (NP) protein of Newcastle disease virus (NDV) was produced by immunization of Balb/c mice with purified recombinant NP protein. Western Blot analysis showed that all the mAbs recognized linearized NP epitopes. Three different NP antigenic sites were identified using deleted truncated NP mutants purified from Escherichia coli. One of the antigenic sites was located at the C-terminal end (residues 441 to 489) of the NP protein. Two other antigenic sites were located within the N-terminal end (residues 26-121 and 122-375). This study demonstrates that the N- and C-terminal ends of the NP proteins are responsible in eliciting immune response, thus it is most likely that these ends are exposed on the NP.
Seroprevalence and risk factors for influenza A viruses in pigs in Peninsular Malaysia

Suriya R, Hassan L, Omar AR, Aini I, Tan CG, Lim YS, et al.

Zoonoses Public Health, 2008 Sep;55(7):342-51.
PMID: 18667027 DOI: 10.1111/j.1863-2378.2008.01138.x

Following a series of H5N1 cases in chickens and birds in a few states in Malaysia, there was much interest in the influenza A viruses subtypes that circulate among the local pig populations. Pigs may act as a mixing vessel for avian and mammal influenza viruses, resulting in new reassorted viruses. This study investigated the presence of antibodies against influenza H1N1 and H3N2 viruses in pigs from Peninsular Malaysia using Herdcheck Swine Influenza H1N1 and H3N2 Antibody Test Kits. At the same time, the presence of influenza virus was examined from the nasal swabs of seropositive pigs by virus isolation and real time RT-PCR. The list of pig farms was obtained from the headquarters of the Department of Veterinary Services, Malaysia, and pig herds were selected randomly from six of 11 states in Peninsular Malaysia. A total of 727 serum and nasal swab samples were collected from 4- to 6-month-old pigs between May and August 2005. By ELISA, the seroprevalences of swine influenza H1N1 and H3N2 among pigs were 12.2% and 12.1% respectively. Seropositivity for either of the virus subtypes was detected in less than half of the 41 sampled farms (41.4%). Combination of both subtypes was detected in 4% of all pigs and in 22% of sampled farms. However, no virus or viral nucleic acid was detected from nasal samples. This study identified that the seropositivity of pigs to H1N1 and H3N2 based on ELISA was significantly associated with factors such as size of farm, importation or purchase of pigs, proximity of farm to other pig farms and the presence of mammalian pets within the farm.
A preparative purification process for recombinant hepatitis B core antigen using online capture by expanded bed adsorption followed by size-exclusion chromatography

Ho CW, Tan WS, Chong FC, Ling TC, Tey BT

J Microbiol Biotechnol, 2009 Apr;19(4):416-23.
PMID: 19421000

Hepatitis B core antigen (HBcAg) is an important serological marker used in the diagnosis of hepatitis B virus (HBV) infections. In the current study, a fast and efficient preparative purification protocol for truncated HBcAg from Escherichia coli disruptate was developed. The recombinant HBcAg was first captured by anion exchange expanded bed adsorption chromatography integrated with a cell disruption process. This online capture process has shortened the process time and eliminated the "hold-up" period that may be detrimental to the quality of target protein. The eluted product from the expanded bed adsorption chromatography was subsequently purified using size-exclusion chromatography. The results showed that this novel purification protocol achieved a recovery yield of 45.1% with a product purity of 88.2%, which corresponds to a purification factor of 4.5. The recovered HBcAg is still biologically active as shown by ELISA test.
Fulltext Sex among Asian men and women: the Global Better Sex Survey in Asia

Tan HM, Marumo K, Yang DY, Hwang TI, Ong ML

Int J Urol, 2009 May;16(5):507-14; discussion 514-5.
PMID: 19467120 DOI: 10.1111/j.1442-2042.2009.02283.x

OBJECTIVES:
To explore by a pooled subanalysis of the Global Better Sex Survey sexual aspirations and unmet needs of men and women from Hong Kong, Indonesia, Japan, Malaysia, Singapore, South Korea, Taiwan, and Thailand.

METHODS:
To qualify, respondents must have had sexual intercourse at least once in the past 12 months. Women must have had heterosexual intercourse. Data were weighted by population size between countries.

RESULTS:
Of 3538 Asian respondents (1776 men and 1762 women), 52% were aged <40 years, 40% were aged 40-59 years, and 8% were aged >or=60 years. The majority were married or in a relationship. Men and women reported having sexual intercourse 5.1 and 4.0 times monthly, respectively. Attraction to partner, foreplay, intercourse, and achieving orgasm were important to most men and women. Two thirds were less than very satisfied with their sex life, and 36% of men were interested in improving sex. For a good sexual experience, the man's ability to get and maintain an erection and erection hardness were important to the majority of Asian men and women. Few respondents reported using a prescription erectile dysfunction medication, but many showed interest in using these medications to improve their sex lives. A comparison between individual countries suggests that attitudes about sex differ from country to country, and between men and women in each country.

CONCLUSIONS:
Sex is very important to Asian men and women, but many of them are not fully satisfied with their sex lives and want to improve them.
N-terminally His-tagged hepatitis B core antigens: construction, expression, purification and antigenicity

Yap WB, Tey BT, Ng MY, Ong ST, Tan WS

J Virol Methods, 2009 Sep;160(1-2):125-31.
PMID: 19433111 DOI: 10.1016/j.jviromet.2009.04.038

The core antigen of the hepatitis B virus (HBcAg) has been used widely as a diagnostic reagent for the identification of the viral infection. However, purification using the conventional sucrose density gradient ultracentrifugation is time consuming and costly. To overcome this, HBcAg particles displaying His-tag on their surface were constructed and produced in Escherichia coli. The recombinant His-tagged HBcAgs were purified using immobilized metal affinity chromatography. Transmission electron microscopy and enzyme-linked immunosorbent assay (ELISA) revealed that the displayed His-tag did not impair the formation of the core particles and the antigenicity of HBcAg.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links