MyMedR

Fulltext Bioprospecting medicinal plants for antioxidant components

Coulibaly AY, Hashim R, Sulaiman SF, Sulaiman O, Ang LZ, Ooi KL

Asian Pac J Trop Med, 2014 Sep;7S1:S553-9.

PMID: 25312183 DOI: 10.1016/S1995-7645(14)60289-3

OBJECTIVE: To evaluate antioxidant activities of seven medicinal plant species and their fractions, and to identify their phenolic compounds.

METHODS: Two extractions were processed and further fractionated by column chromatography to evaluate the concentration that inhibit 50% of 2,2'-azinobis (3-ethylbenzothiazoline-6-suslfonic acid, 1,1-diphenyl-2-picryl-hydrazyl radicals, and their ferric reducing antioxidant power. The identification of the fractions of phenolic compounds was done by ultra performance liquid chromatography.

RESULTS: The aqueous-acetone extracts of Feretia apodanthera and Ozoroa insignis exhibited the highest antioxidant potentials comparable to those of the standard quercetin. Their subsequently silica gel column fractionation showed three most active fractions from which the major constituents quercetin, myricetin, kampferol, rutin and isoquercetin were identified.

CONCLUSIONS: These plant species have potent antioxidant profiles and polyphenol compounds that may help to manage with radical related disease and aging.

Fulltext Determinants of posterior corneal biometric measurements in a multi-ethnic Asian population

Ang M, Chong W, Huang H, Wong TY, He MG, Aung T, et al.

PLoS One, 2014;9(7):e101483.

PMID: 25006679 DOI: 10.1371/journal.pone.0101483

To describe the corneal and anterior segment determinants of posterior corneal arc length (PCAL) and posterior corneal curvature (PCC).

Influence of extraction conditions on antioxidant properties of passion fruit (Passiflora edulis) peel

Wong YS, Sia CM, Khoo HE, Ang YK, Chang SK, Chang SK, et al.

Acta Sci Pol Technol Aliment, 2014 Jul-Sep;13(3):257-65.

PMID: 24887941

As a by-product of tropical fruit juice industry, passion fruit peel is a valuable functional food. It is rich in antioxidants. To determine its potential antioxidant properties of passion fruit peel, this study aimed to evaluate the effect of extraction conditions on total phenolic content and antioxidant activity.

Fulltext A pilot randomized control cross over study evaluating the effectiveness and safety of mechanical percussor compared with conventional chest physiotherapy in adults with productive cough

Punithavathi N, Ong LM, Irfhan Ali HA, Mohd Izmi IA, Dharminy T, Ang AH, et al.

Med J Malaysia, 2014 Feb;69(1):16-20.

PMID: 24814623 MyJurnal

INTRODUCTION: Conventional Chest Physiotherapy (CCPT) remains the mainstay of treatment for sputum mobilization in patients with productive cough such as bronchiectasis and "Chronic Obstructive Airway Disease" (COPD). However CCPT is time consuming requires the assistance of a physiotherapist and limits the independence of the patient. Mechanical percussors which are electrical devices used to provide percussion to the external chest wall might provide autonomy and greater compliance. We compared safety and efficacy of a mechanical chest percusser devised by Formedic Technology with conventional chest percussion.
METHODS: Twenty patients (mean age 64years) were randomly assigned to receive either CCPT or mechanical percussor on the first day and crossed over by "Latin square randomisation" to alternative treatment for 6 consecutive days and the amount of sputum expectorated was compared by dry and wet weight. Adverse events and willingness to use was assessed by a home diary and a questionnaire.
RESULTS: There were 13 males and 7 females, eight diagnosed as bronchiectasis and 12 COPD. The mean dry weight of sputum induced by CCPT (0.54g ± 0.32) was significantly more compared with MP (0.40g + 0.11); p-value = 0.002. The mean wet weight of sputum with CCPT (10.71g ± 8.70) was also significantly more compared with MP (5.99g ± 4.5); p-value < 0.001. There were no significant difference in adverse events and majority of patients were willing to use the device by themselves.
CONCLUSION: The mechanical percussor although produces less sputum is well tolerated and can be a useful adjunct to CCPT.

Health burden associated with visual impairment in Singapore: the Singapore epidemiology of eye disease study

Wang X, Lamoureux E, Zheng Y, Ang M, Wong TY, Luo N

Ophthalmology, 2014 Sep;121(9):1837-42.

PMID: 24768238 DOI: 10.1016/j.ophtha.2014.03.017

To assess the impact of visual impairment (VI) on health-related quality of life and to compare the health burden of VI and other health conditions in Singapore.

Fulltext Factors influencing the role of primary care providers as gatekeepers in the Malaysian public healthcare system

Ang KT, Ho BK, Mimi O, Salmah N, Salmiah MS, Noridah MS

Malays Fam Physician, 2014;9(3):2-11.

PMID: 26425299 MyJurnal

Primary care providers play an important gatekeeping role in ensuring appropriate referrals to secondary care facilities. This cross-sectional study aimed to determine the level, pattern and rate of referrals from health clinics to hospitals in the public sector, and whether the placement of resident family medicine specialist (FMS) had made a significant difference. The study was carried out between March and April in 2012, involving 28 public primary care clinics. It showed that the average referral rate was 1.56% for clinics with resident FMS and 1.94% for those without resident FMS, but it was not statistically significant. Majority of referred cases were considered appropriate (96.1%). Results of the multivariate analysis showed that no prior consultation with senior healthcare provider and illnesses that were not severe and complex were independently associated with inappropriate referrals. Severity, complexity or uncertain diagnosis of patients' illness or injury significantly contributed to unavoidable referrals. Adequate facilities or having more experienced doctors could have avoided 14.5% of the referrals. The low referral rate and very high level of appropriate referrals could indicate that primary care providers in the public sector played an effective role as gatekeepers in the Malaysian public healthcare system.

Zinc (II) complex with a cationic Schiff base ligand: synthesis, characterization, and biological studies

Lee SK, Tan KW, Ng SW, Ooi KK, Ang KP, Abdah MA

Spectrochim Acta A Mol Biomol Spectrosc, 2014;121:101-8.

PMID: 24231745 DOI: 10.1016/j.saa.2013.10.084

A cationic Schiff base ligand, TSB (L) and its Zn (II) complex (1) were synthesized and characterized by using CHN, (1)H-NMR, FT-IR, UV, LC-MS, and X-ray methods. Their ability to inhibit topoisomerase I, DNA cleavage activities, and cytotoxicity were studied. X-ray diffraction study shows that the mononuclear complex 1 is four coordinated with distorted tetrahedral geometry. The singly deprotonated Schiff base ligand L acts as a bidentate ON-donor ligand. Complexation of L increases the inhibitory strength on topoisomerase I activity. Complex 1 could fully inhibit topoisomerase I activity at 250 μM, while L did not show any inhibitory effect on topoisomerase I activity. In addition, L and complex 1 could cleave pBR322 DNA in a concentration and time dependent profile. Surprisingly, L has better DNA cleavage activity than complex 1. The cleavage of DNA by complex 1 is altered in the presence of hydrogen peroxide. Furthermore, L and complex 1 are mildly cytotoxic towards human ovarian cancer A2780 and hepatocellular carcinoma HepG2.

Apoptosis induction in MV4-11 and K562 human leukemic cells by Pereskia sacharosa (Cactaceae) leaf crude extract

Asmaa MJ, Al-Jamal HA, Ang CY, Asan JM, Seeni A, Johan MF

Asian Pac J Cancer Prev, 2014;15(1):475-81.

PMID: 24528077

BACKGROUND: Pereskia sacharosa is a genus of cacti widely used in folk medicine for cancer-related treatment. Anti-proliferative effects have been studied in recent years against colon, breast, cervical and lung cancer cell lines, with promising results. We here extended study of anti-proliferative effects to a blood malignancy, leukemia.

MATERIALS AND METHODS: Two leukemic cell lines, MV4-11 (acute myeloid leukemia) and K562 (chronic myeloid leukemia), were studied. IC50 concentrations were determined and apoptosis and cell cycle regulation were studied by flow cytometric analysis. The expression of apoptosis and cell-cycle related regulatory proteins was assessed by Western blotting.

RESULTS: P sacharosa inhibited growth of MV4-11 and K562 cells in a dose-dependent manner. The mode of cell death was via induction of intrinsic apoptotic pathways and cell cycle arrest. There was profound up-regulation of cytochrome c, caspases, p21 and p53 expression and repression of Akt and Bcl-2 expression in treated cells.

CONCLUSIONS: These results suggest that P sacharosa induces leukemic cell death via apoptosis induction and changes in cell cycle checkpoint, thus deserves further study for anti-leukemic potential.

Fulltext First Whole-Genome Sequence of Mycobacterium iranicum, a Newly Reported Mycobacterial Species

Tan JL, Ng HF, Wee WY, Ang MY, Wong GJ, Ngeow YF, et al.

Genome Announc, 2013;1(5).

PMID: 24072861 DOI: 10.1128/genomeA.00732-13

Mycobacterium iranicum is a new species of nontuberculous mycobacterium reported in 2013. Here, we describe the first whole-genome sequence of this species, that of M. iranicum strain UM_TJL, isolated from a patient in Malaysia.

Screening of stepping forces in an arthritic rat model using a novel analgesic meter and data acquisition system

Yam MF, Ahmad M, Por LY, Ang LF, Basir R, Asmawi MZ

Sensors (Basel), 2012;12(7):9603-12.

PMID: 23012561

The stepping forces of normal and Freund Complete Adjuvant (FCA)-induced arthritic rats were studied in vivo using a proposed novel analgesic meter. An infrared charge-coupled device (CCD) camera and a data acquisition system were incorporated into the analgesic meter to determine and measure the weight of loads on the right hind paw before and after induction of arthritis by FCA injection into the paw cavity. FCA injection resulted in a significant reduction in the stepping force of the affected hind paw. The stepping force decreased to the minimum level on day 4 after the injection and then gradually increased up to day 25. Oral administration of prednisolone significantly increased the stepping forces of FCA-induced arthritic rats on days 14 and 21. These results suggest that the novel device is an effective tool for measuring the arthritic pain in in vivo studies even though walking is a dynamic condition.

Fulltext Phylogenetic relationships of the Orang Asli and Iban of Malaysia based on maternal markers

Ang KC, Leow JW, Yeap WK, Hood S, Mahani MC, Md-Zain BM

Genet. Mol. Res., 2011;10(2):640-9.

PMID: 21491374 DOI: 10.4238/vol10-2gmr1011

Malaysia remains as a crossroad of different cultures and peoples, and it has long been recognized that studying its population history can provide crucial insight into the prehistory of Southeast Asia as a whole. The earliest inhabitants were the Orang Asli in Peninsular Malaysia and the indigenous groups in Sabah and Sarawak. Although they were the earliest migrants in this region, these tribes are divided geographically by the South China Sea. We analyzed DNA sequences of 18 Orang Asli using mitochondrial DNA extracted from blood samples, each representing one sub-tribe, and from five Sarawakian Iban. Mitochondrial DNA was extracted from hair samples in order to examine relationships with the main ethnic groups in Malaysia. The D-loop region and cytochrome b genes were used as the candidate loci. Phylogenetic relationships were investigated using maximum parsimony and neighbor joining algorithms, and each tree was subjected to bootstrap analysis with 1000 replicates. Analyses of the HVS I region showed that the Iban are not a distinct group from the Orang Asli; they form a sub-clade within the Orang Asli. Based on the cytochrome b gene, the Iban clustered with the Orang Asli in the same clade. We found evidence for considerable gene flow between Orang Asli and Iban. We concluded that the Orang Asli, Iban and the main ethnic groups of Malaysia are probably derived from a common ancestor. This is in agreement with a single-route migration theory, but it does not dismiss a two-route migration theory.

Fulltext Isolation and characterization of microsatellite loci in an endangered palm, Johannesteijsmannia lanceolata (Arecaceae)

Ang CC, Lee SL, Lee CT, Tnah LH, Zakaria RM, Ng CC

Am J Bot, 2011 May;98(5):e117-9.

PMID: 21613176 DOI: 10.3732/ajb.1000494

Microsatellite markers were developed for Johannesteijsmannia lanceolata to assess the genetic diversity and mating system of this alarmingly endangered species.

Identification of copy number alterations by array comparative genomic hybridization in patients with late chronic or accelerated phase chronic myeloid leukemia treated with imatinib mesylate

Nadarajan VS, Phan CL, Ang CH, Liang KL, Gan GG, Bee PC, et al.

Int J Hematol, 2011 Apr;93(4):465-473.

PMID: 21387093 DOI: 10.1007/s12185-011-0796-9

The outcome of treating chronic myeloid leukemia (CML) with imatinib mesylate (IM) is inferior when therapy is commenced in late chronic or accelerated phase as compared to early chronic phase. This may be attributed to additional genomic alterations that accumulate during disease progression. We sought to identify such lesions in patients showing suboptimal response to IM by performing array-CGH analysis on 39 sequential samples from 15 CML patients. Seventy-four cumulative copy number alterations (CNAs) consisting of 35 losses and 39 gains were identified. Alterations flanking the ABL1 and BCR genes on chromosomes 9 and 22, respectively, were the most common identified lesions with 5 patients losing variable portions of 9q34.11 proximal to ABL1. Losses involving 1p36, 5q31, 17q25, Y and gains of 3q21, 8q24, 22q11, Xp11 were among other recurrent lesions identified. Aberrations were also observed in individual patients, involving regions containing known leukemia-associated genes; CDKN2A/2B, IKZF1, RB1, TLX1, AFF4. CML patients in late stages of their disease, harbor pre-existing and evolving sub-microscopic CNAs that may influence disease progression and IM response.

Epidemiology and control of chikungunya fever in Singapore

Ho K, Ang LW, Tan BH, Tang CS, Ooi PL, James L, et al.

J Infect, 2011 Apr;62(4):263-70.

PMID: 21315108 DOI: 10.1016/j.jinf.2011.02.001

OBJECTIVES: We conducted an epidemiological review of the chikungunya fever situation in Singapore and described the measures taken to prevent the chikungunya virus from becoming entrenched in the tropical city-state.
METHODS: All laboratory-confirmed cases and outbreak investigation reports maintained by the Communicable Diseases Division, Ministry of Health, and Aedes mosquito surveillance data obtained by the National Environment Agency during the period 2006 and 2009 were reviewed and analysed.
RESULTS: Sporadic cases were imported into Singapore until the first local transmission occurred in an urban area where Aedes aegypti was the predominant vector. Subsequent introduction of a mutant viral strain (A226V) in early 2008 resulted in the rapid spread to suburban and rural areas where Aedes albopictus was the primary vector. 1072 cases including 812 (75.7%) indigenous cases were reported. The main sources of importation were India and Malaysia. Foreign contract workers were identified as high-risk for indigenous infections.
CONCLUSIONS: The disease was successfully brought under control through aggressive vector control measures directed at A. albopictus. Although the incidence has sharply declined since January 2009, a high degree of vigilance is maintained to prevent a recurrence of epidemic transmission which can occur even with a well-established nationwide mosquito control programme.

Dietary exposure to heterocyclic amines in high-temperature cooked meat and fish in Malaysia

Jahurul MH, Jinap S, Ang SJ, Abdul-Hamid A, Hajeb P, Lioe HN, et al.

Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 2010 Aug;27(8):1060-71.

PMID: 20589547 DOI: 10.1080/19440041003801190

The intake of heterocyclic amines is influenced by the amount and type of meat and fish ingested, frequency of consumption, cooking methods, cooking temperature, and duration of cooking. In this study, the dietary intake of heterocyclic amines in Malaysia and their main sources were investigated. Forty-two samples of meat and fish were analysed by high-performance liquid chromatography with photodiode array detector to determine the concentration of the six predominant heterocyclic amines, namely: 2-amino-3-methylimidazo[4,5-f] quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f] quinoline(MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f] quinoxaline (4,8-DiMeIQx), 2-amino-3,7,8-trimethylimidazo[4,5-f] quinoxaline (7,8-DiMeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Dietary intake data were obtained using a food-frequency questionnaire when interviewing 600 Malaysian respondents. The level of total heterocyclic amines in food samples studies ranged from not detected to 38.7 ng g(-1). The average daily intake level of heterocyclic amine was 553.7 ng per capita day(-1). The intake of PhIP was the highest, followed by MeIQx and MeIQ. The results reveal that fried and grilled chicken were the major dietary source of heterocyclic amines in Malaysia. However, the heterocyclic amine intake by the Malaysian population was lower than those reported from other regions.

Fulltext Anti-inflammatory and analgesic effects of Elephantopus tomentosus ethanolic extract

Yam MF, Ang LF, Ameer OZ, Salman IM, Aziz HA, Asmawi MZ

J Acupunct Meridian Stud, 2009 Dec;2(4):280-7.

PMID: 20633503 DOI: 10.1016/S2005-2901(09)60069-8

Elephantopus tomentosus is widely used in Asia, especially in Malaysia, for the treatment of pain and inflammation. In the present study, the analgesic and anti-inflammatory effects of a 95% ethanol extract of E. tomentosus were investigated in different experimental models. In the anti-inflammation study, 1000 mg/kg of extract significantly reduced carrageenan-induced hind paw edema (p < 0.05) and inhibited abdominal permeability compared with control (p < 0.01). The analgesic activity was assayed in several experimental models in mice: (1) hot plate, (2) tail flick, (3) writhing test; and rats: carrageenan-induced hyperalgesia pain threshold test. However, at the doses tested, no significant activity was found in the hot plate test and the tail flick test. E. tomentosus ethanol extract at 1000 mg/kg significantly (p < 0.05) increased hyperalgesia pain threshold and inhibited writhing activity. The results suggest that E. tomentosus ethanol extract at 1000 mg/kg dose is effective in anti-inflammatory and non-steroidal anti-inflammatory drug type anti-nociception activities.

Differential expression of a subset of ribosomal protein genes in cell lines derived from human nasopharyngeal epithelium

Sim EU, Ang CH, Ng CC, Lee CW, Narayanan K

J Hum Genet, 2010 Feb;55(2):118-20.

PMID: 19927161 DOI: 10.1038/jhg.2009.124

Extraribosomal functions of human ribosomal proteins (RPs) include the regulation of cellular growth and differentiation, and are inferred from studies that linked congenital disorders and cancer to the deregulated expression of RP genes. We have previously shown the upregulation and downregulation of RP genes in tumors of colorectal and nasopharyngeal carcinomas (NPCs), respectively. Herein, we show that a subset of RP genes for the large ribosomal subunit is differentially expressed among cell lines derived from the human nasopharyngeal epithelium. Three such genes (RPL27, RPL37a and RPL41) were found to be significantly downregulated in all cell lines derived from NPC tissues compared with a nonmalignant nasopharyngeal epithelial cell line. The expression of RPL37a and RPL41 genes in human nasopharyngeal tissues has not been reported previously. Our findings support earlier suspicions on the existence of NPC-associated RP genes, and indicate their importance in human nasopharyngeal organogenesis.

Further observations in an area with an exceptionally low prevalence of Helicobacter pylori infection

Raj SM, Lee YY, Choo KE, Noorizan AM, Zulkifli A, Radzi M, et al.

Trans R Soc Trop Med Hyg, 2008 Nov;102(11):1163-4.

PMID: 18678380 DOI: 10.1016/j.trstmh.2008.06.015

Evaluation of the anti-pyretic potential of Orthosiphon stamineus Benth standardized extract

Yam MF, Ang LF, Basir R, Salman IM, Ameer OZ, Asmawi MZ

Inflammopharmacology, 2009 Feb;17(1):50-4.

PMID: 19127348 DOI: 10.1007/s10787-008-8038-3

The anti-pyretic activity of a standardized methanol/water (50/50) extract of Orthosiphon stamineus Benth. (SEOS) was investigated for its effect on normal body temperature and yeast-induced pyrexia in Sprague Dawley (SD) rats. The SEOS showed no effect on normal body temperature. Doses of 500 and 1000 mg/kg body weight of SEOS significantly reduced the yeast-induced elevation in body temperature. This effect persisted up to 4 h following the administration of the extract. The anti-pyretic effect of SEOS was comparable with that of paracetamol (acetaminophen in U.S) (150 mg/kg p.o.), a standard anti-pyretic agent. HPLC study revealed that rosmarinic acid, sinensetin, eupatorin and tetramethoxyflavone were present in SEOS in the amounts of 7.58%, 0.2%, 0.34% and 0.24% respectively. The LD(50) of the extract in rats was higher than 5000 mg/kg body weight. Therefore, the present study ascertained that SEOS possesses a significant anti-pyretic activity.

Effect of local anesthesia and intravenous sedation on pain perception and vasovagal reactions during femoral arterial sheath removal after percutaneous coronary intervention

Kiat Ang C, Leung DY, Lo S, French JK, Juergens CP

Int J Cardiol, 2007 Apr 4;116(3):321-6.

PMID: 16904773

There is no consensus with respect to the use of analgesia during femoral arterial sheath removal after percutaneous coronary intervention (PCI). We performed a randomized controlled trial to assess the impact of intravenous sedation and local anesthesia during femoral sheath removal after PCI on patient comfort and the incidence of vasovagal reactions.

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