MyMedR

Displaying publications 41 - 60 of 139 in total

Abstract:

Sort:

Fulltext Improved photodynamic efficacy of Zn(II) phthalocyanines via glycerol substitution

Chin Y, Lim SH, Zorlu Y, Ahsen V, Kiew LV, Chung LY, et al.

PLoS One, 2014;9(5):e97894.
PMID: 24840576 DOI: 10.1371/journal.pone.0097894

Phthalocyanines are excellent photosensitizers for photodynamic therapy as they have strong absorbance in the near infra-red region which is most relevant for in vivo activation in deeper tissular regions. However, most phthalocyanines present two major challenges, ie, a strong tendency to aggregate and low water-solubility, limiting their effective usage clinically. In the present study, we evaluated the potential enhancement capability of glycerol substitution on the photodynamic properties of zinc (II) phthalocyanines (ZnPc). Three glycerol substituted ZnPc, 1-3, (tetra peripherally, tetra non-peripherally and mono iodinated tri non-peripherally respectively) were evaluated in terms of their spectroscopic properties, rate of singlet oxygen generation, partition coefficient (log P), intracellular uptake, photo-induced cytotoxicity and vascular occlusion efficiency. Tetrasulfonated ZnPc (ZnPcS4) was included as a reference compound. Here, we showed that 1-3 exhibited 10-100 nm red-shifted absorption peaks with higher molar absorptivity, and at least two-fold greater singlet oxygen generation rates compared to ZnPcS4. Meanwhile, phthalocyanines 1 and 2 showed more hydrophilic log P values than 3 consistent with the number of glycerol attachments but 3 was most readily taken up by cells compared to the rest. Both phthalocyanines 2 and 3 exhibited potent phototoxicity against MCF-7, HCT-116 and HSC-2 cancer cell-lines with IC50 ranging 2.8-3.2 µM and 0.04-0.06 µM respectively, while 1 and ZnPcS4 (up to 100 µM) failed to yield determinable IC50 values. In terms of vascular occlusion efficiency, phthalocyanine 3 showed better effects than 2 by causing total occlusion of vessels with diameter <70 µm of the chorioallantoic membrane. Meanwhile, no detectable vascular occlusion was observed for ZnPcS4 with treatment under similar experimental conditions. These findings provide evidence that glycerol substitution, in particular in structures 2 and 3, is able to improve the photodynamic properties of ZnPc.
Membrane disruption and anti-quorum sensing effects of synergistic interaction between Lavandula angustifolia (lavender oil) in combination with antibiotic against plasmid-conferred multi-drug-resistant Escherichia coli

Yap PS, Krishnan T, Yiap BC, Hu CP, Chan KG, Lim SH

J Appl Microbiol, 2014 May;116(5):1119-28.
PMID: 24779580 DOI: 10.1111/jam.12444

The aim of this study was to investigate the mode of action of the lavender essential oil (LV) on antimicrobial activity against multi-drug-resistant Escherichia coli J53 R1 when used singly and in combination with piperacillin.
Macroline, akuammiline, sarpagine, and ajmaline alkaloids from Alstonia macrophylla

Lim SH, Low YY, Sinniah SK, Yong KT, Sim KS, Kam TS

Phytochemistry, 2014 Feb;98:204-15.
PMID: 24342109 DOI: 10.1016/j.phytochem.2013.11.014

A total of seventeen alkaloids, comprising six macroline (including alstofolinine A, a macroline indole incorporating a butyrolactone ring-E), two ajmaline, one sarpagine, and eight akuammiline alkaloids, were isolated from the stem-bark and leaf extracts of the Malayan Alstonia macrophylla. The structure and relative configurations of these alkaloids were established using NMR, MS and in several instances, confirmed by X-ray diffraction analysis. Six of these alkaloids were effective in reversing multidrug-resistance (MDR) in vincristine-resistant KB cells.
Fulltext Evolutionary history of HIV-1 subtype B and CRF01_AE transmission clusters among men who have sex with men (MSM) in Kuala Lumpur, Malaysia

Ng KT, Ong LY, Lim SH, Takebe Y, Kamarulzaman A, Tee KK

PLoS One, 2013;8(6):e67286.
PMID: 23840653 DOI: 10.1371/journal.pone.0067286

HIV-1 epidemics among men who have sex with men (MSM) continue to expand in developed and developing countries. Although HIV infection in MSM is amongst the highest of the key affected populations in many countries in Southeast Asia, comprehensive molecular epidemiological study of HIV-1 among MSM remains inadequate in the region including in Malaysia. Here, we reported the phylodynamic profiles of HIV-1 genotypes circulating among MSM population in Kuala Lumpur, Malaysia. A total of n = 459 newly-diagnosed treatment-naïve consenting subjects were recruited between March 2006 and August 2012, of whom 87 (18.9%) were self-reported MSM. Transmitted drug resistance mutations were absent in these isolates. Cumulatively, phylogenetic reconstructions of the pro-rt gene (HXB2∶2253-3275) showed that HIV-1 subtype B and CRF01_AE were predominant and contributed to approximately 80% of the total HIV-1 infection among MSM. In addition to numerous unique transmission lineages within these genotypes, twelve monophyletic transmission clusters of different sizes (2-7 MSM sequences, supported by posterior probability value of 1) were identified in Malaysia. Bayesian coalescent analysis estimated that the divergence times for these clusters were mainly dated between 1995 and 2005 with four major transmission clusters radiating at least 12 years ago suggesting that active spread of multiple sub-epidemic clusters occurred during this period. The changes in effective population size of subtype B showed an exponential growth within 5 years between 1988 and 1993, while CRF01_AE lineage exhibited similar expansion between 1993 and 2003. Our study provides the first insight of the phylodynamic profile of HIV-1 subtype B and CRF01_AE circulating among MSM population in Kuala Lumpur, Malaysia, unravelling the importance of understanding transmission behaviours as well as evolutionary history of HIV-1 in assessing the risk of outbreak or epidemic expansion.
High rates of unprotected anal intercourse with regular and casual partners and associated risk factors in a sample of ethnic Malay men who have sex with men (MSM) in Penang, Malaysia

Lim SH, Bazazi AR, Sim C, Choo M, Altice FL, Kamarulzaman A

Sex Transm Infect, 2013 Dec;89(8):642-9.
PMID: 23787168 DOI: 10.1136/sextrans-2012-050995

OBJECTIVE: To assess the prevalence of unprotected anal intercourse (UAI) and its correlates among ethnic Malay men who have sex with men (MSM).
METHODS: In 2010, a convenience sample of 350 MSM in Penang were recruited to participate in an anonymous, computerised survey with rapid HIV testing. Participants who were not of Malay ethnicity (n=44) or who did not report sex with another man in the previous 12 months (n=22) were excluded, resulting in 284 participants in the final analysis. Correlates of UAI were examined separately for regular and casual partnerships using bivariate and multivariate logistic regression.
RESULTS: Four men (1.9%) tested HIV positive. In the past 12 months, 64.7% of participants had regular sexual partners, 77.1% had casual sexual partners and 41.9% had both. Most participants (83.1%) reported UAI, which was more common in regular partnerships. Over two-thirds of participants had never been tested for HIV. In multivariate analysis, agreement about sexual risk reduction practices was associated with a reduction in UAI with regular partners (adjusted OR (AOR)=0.14, 95% CI 0.05 to 0.40). Reporting difficulty in using condoms was associated with an increase in UAI with casual partners (AOR=9.07, 95% CI 3.35 to 24.5), and any exposure to HIV prevention was associated with a decrease in UAI with casual partners (AOR=0.22, 95% CI 0.09 to 0.54).
CONCLUSIONS: Despite highly prevalent HIV risk behaviours, HIV seropositivity and prior HIV testing were low. Increasing sexual negotiation skills and access to HIV testing and other prevention services may improve future prevention efforts.
KEYWORDS: HIV; Homosexuality; Prevention; Sexual Behaviour
Perhentidines A-C: macroline-macroline bisindoles from Alstonia and the absolute configuration of perhentinine and macralstonine

Lim SH, Low YY, Tan SJ, Lim KH, Thomas NF, Kam TS

J Nat Prod, 2012 May 25;75(5):942-50.
PMID: 22559995 DOI: 10.1021/np300120p

Three new bisindole alkaloids of the macroline-macroline type, perhentidines A-C (1-3), were isolated from the stem-bark extract of Alstonia macrophylla and Alstonia angustifolia. The structures of these alkaloids were established on the basis of NMR and MS analyses. The absolute configurations of perhentinine (4) and macralstonine (5) were established by X-ray diffraction analyses, which facilitated assignment of the configuration at C-20 in the regioisomeric bisindole alkaloids perhentidines A-C (1-3). A potentially useful method for the determination of the configuration at C-20 based on comparison of the NMR chemical shifts of the bisindoles and their acetate derivatives, in these and related bisindoles with similar constitution and branching of the monomeric units, is also presented.
Proteomic analysis of the molecular response of Raji cells to maslinic acid treatment

Yap WH, Khoo KS, Lim SH, Yeo CC, Lim YM

Phytomedicine, 2012 Jan 15;19(2):183-91.
PMID: 21893403 DOI: 10.1016/j.phymed.2011.08.058

Maslinic acid, a natural pentacyclic triterpene has been shown to inhibit growth and induce apoptosis in some tumour cell lines. We studied the molecular response of Raji cells towards maslinic acid treatment. A proteomics approach was employed to identify the target proteins. Seventeen differentially expressed proteins including those involved in DNA replication, microtubule filament assembly, nucleo-cytoplasmic trafficking, cell signaling, energy metabolism and cytoskeletal organization were identified by MALDI TOF-TOF MS. The down-regulation of stathmin, Ran GTPase activating protein-1 (RanBP1), and microtubule associated protein RP/EB family member 1 (EB1) were confirmed by Western blotting. The study of the effect of maslinic acid on Raji cell cycle regulation showed that it induced a G1 cell cycle arrest. The differential proteomic changes in maslinic acid-treated Raji cells demonstrated that it also inhibited expression of dUTPase and stathmin which are known to induce early S and G2 cell cycle arrests. The mechanism of maslinic acid-induced cell cycle arrest may be mediated by inhibiting cyclin D1 expression and enhancing the levels of cell cycle-dependent kinase (CDK) inhibitor p21 protein. Maslinic acid suppressed nuclear factor-kappa B (NF-κB) activity which is known to stimulate expression of anti-apoptotic and cell cycle regulatory gene products. These results suggest that maslinic acid affects multiple signaling molecules and inhibits fundamental pathways regulating cell growth and survival in Raji cells.
Glycosylation is not necessary for recognition of the fusion glycoprotein domain of the human respiratory syncytial virus by a polyclonal antibody

Lim SH, Jahanshiri F, Jalilian FA, Rahim RA, Sekawi Z, Yusoff K

Acta Virol., 2010;54(3):181-7.
PMID: 20822310

Human respiratory syncytial virus (HRSV) is a leading pathogen causing lower respiratory tract infections in infants and young children worldwide. In line with the development of an effective vaccine against HRSV, a domain of the fusion (F) glycoprotein of HRSV was produced and its immunogenicity and antigenic properties, namely the effect of deficient glycosylation was examined. A His-tagged recombinant F (rF) protein was expressed in Escherichia coli, solubilized with 8 mol/l urea, purified by the Ni-NTA affinity chromatography and used for the raising of a polyclonal antibody in rabbits. The non-glycosylated rF protein proved to be a strong immunogen that induced a polyclonal antibody that was able to recognize also the glycosylated F1 subunit of native HRSV. The other way around, a polyclonal antibody prepared against the native HRSV was able to react with the rF protein. These results indicated that glycosylation was not necessary for the F domain aa 212-574 in order to be recognized by the specific polyclonal antibody.
Cell growth, cell-cycle progress, and antibody production in hybridoma cells cultivated under mild hypothermic conditions

Chong SL, Mou DG, Ali AM, Lim SH, Tey BT

Hybridoma (Larchmt), 2008 Apr;27(2):107-11.
PMID: 18642675

The effect of mild hypothermic (32 degrees C) conditions on cell growth, cell-cycle progress, and antibody production of hybridoma C2E7 cells was investigated in the present study. The growth of hybridoma cells was slower during the mild hypothermic condition compared to that at 37 degrees C; this led to about 10% decrease in maximum viable cell density and volumetric antibody productivity. However, under mild hypothermic growth conditions, the culture viability was substantially improved and the specific antibody productivity was enhanced compared to that at 37 degrees C. The average specific productivity for the entire batch culture at 32 degrees C is about 5% higher than that at 37 degrees C. Cell-cycle analysis data showed that there was no growth arrestment during the mild hypothermic growth of hybridoma cells. The G1-phase cells were increased, while the S-phase cells were decreased gradually as the culture time progressed. Further analysis showed that the specific antibody productivity of hybridoma cells was correlated to the fraction of S-phase cells.
Leuconoxine, kopsinitarine, kopsijasmine, and kopsinone derivatives from Kopsia

Lim SH, Sim KM, Abdullah Z, Hiraku O, Hayashi M, Komiyama K, et al.

J Nat Prod, 2007 Aug;70(8):1380-3.
PMID: 17608533

Four new indole alkaloids were obtained from two Kopsia species, 6-oxoleuconoxine (1) from the leaf extract of K. griffithii and kopsinitarine E (2), kopsijasminine (3), and kopsonoline (4) from the stem-bark extract of K. teoi. The structures of these alkaloids were determined using NMR and MS analysis. Kopsijasminine (3) showed moderate activity in reversing multidrug resistance in vincristine-resistant KB cells.
Lumusidines A-D and villalstonidine F, macroline-macroline and macroline-pleiocarpamine bisindole alkaloids from Alstonia macrophylla

Lim SH, Low YY, Subramaniam G, Abdullah Z, Thomas NF, Kam TS

Phytochemistry, 2013 Mar;87:148-56.
PMID: 23200029 DOI: 10.1016/j.phytochem.2012.11.005

Lumusidines A-D, bisindole alkaloids of the macroline-macroline type, and one of the macroline-pleiocarpamine type, villalstonidine F, were isolated from the stem-bark extract of Alstonia macrophylla (Apocynaceae). The structures and absolute configurations of these alkaloids were established using NMR, MS, and X-ray diffraction analyses.
Fulltext Stigma toward men who have sex with men among future healthcare providers in Malaysia: would more interpersonal contact reduce prejudice?

Earnshaw VA, Jin H, Wickersham JA, Kamarulzaman A, John J, Lim SH, et al.

AIDS Behav, 2016 Jan;20(1):98-106.
PMID: 26324078 DOI: 10.1007/s10461-015-1168-x

Men who have sex with men (MSM) living in countries with strong stigma toward MSM are vulnerable to HIV and experience significant barriers to HIV care. Research is needed to inform interventions to reduce stigma toward MSM in these countries, particularly among healthcare providers. A cross-sectional survey of 1158 medical and dental students was conducted at seven Malaysian universities in 2012. Multivariate analyses of variance suggest that students who had interpersonal contact with MSM were less prejudiced toward and had lower intentions to discriminate against MSM. Path analyses with bootstrapping suggest stereotypes and fear mediate associations between contact with prejudice and discrimination. Intervention strategies to reduce MSM stigma among healthcare providers in Malaysia and other countries with strong stigma toward MSM may include facilitating opportunities for direct, in-person or indirect, media-based prosocial contact between medical and dental students with MSM.
Fulltext Impact of HIV-1 Subtype on the Time to CD4+ T-Cell Recovery in Combination Antiretroviral Therapy (cART)-Experienced Patients

Chow WZ, Lim SH, Ong LY, Yong YK, Takebe Y, Kamarulzaman A, et al.

PLoS One, 2015;10(9):e0137281.
PMID: 26335136 DOI: 10.1371/journal.pone.0137281

Human immunodeficiency virus type 1 (HIV-1) subtypes have been shown to differ in the rate of clinical progression. We studied the association between HIV-1 subtypes and the rate of CD4+ T-cell recovery in a longitudinal cohort of patients on combination antiretroviral therapy (cART). We studied 103 patients infected with CRF01_AE (69%) and subtype B (31%) who initiated cART between 2006 and 2013. Demographic data, CD4+ T-cell counts and HIV-1 viral load were abstracted from patient medical charts. Kaplan-Meier was used to estimate the time to CD4+ T-cell count increase to ≥350 between subtypes and effects of covariates were analysed using Cox proportional hazards. An 87% of the study population were male adults (mean age of 38.7 years old). Baseline CD4+ T-cell counts and viral loads, age at cART initiation, sex, ethnicity and co-infection did not differ significantly between subtypes. A shorter median time for CD4+ T-cell count increase to ≥350 cells/μL was observed for CRF01_AE (546 days; 95% confidence interval [CI], 186-906 days; P = .502) compared to subtype B (987 days; 95% CI, 894-1079 days). In multivariate analysis, female sex was significantly associated with a 2.7 times higher chance of achieving CD4+ T-cell recovery (adjusted hazard ratio [HR], 2.75; 95% CI, 1.21-6.22; P = .025) and both baseline CD4+ T-cell count (P = .001) and viral load (P = .001) were important predictors for CD4+ T-cell recovery. Immunological recovery correlated significantly with female sex, baseline CD4+ T-cell counts and viral load but not subtype.
Ibogan, Aspidosperman, Vincamine, and Bisindole Alkaloids from a Malayan Tabernaemontana corymbosa: Iboga Alkaloids with C-20α Substitution

Nge CE, Chong KW, Thomas NF, Lim SH, Low YY, Kam TS

J Nat Prod, 2016 05 27;79(5):1388-99.
PMID: 27077800 DOI: 10.1021/acs.jnatprod.6b00129

Ten new indole alkaloids (1-10) comprising five ibogan, two aspidosperman, one vincamine, and two bisindole alkaloids, in addition to 32 known alkaloids, were isolated from the stem-bark extract of a Malayan Tabernaemontana corymbosa. The structures of these alkaloids were determined based on analysis of the NMR and MS data and, in five instances (1, 3, 5, 6, 8), confirmed by X-ray diffraction analysis. Two of the iboga alkaloids, conodusines B (2) and C (3), and the iboga-containing bisindole tabernamidine B (10) are notable for the presence of an α-substituted acetyl group at C-20 of the iboga carbon skeleton. The iboga alkaloid (+)-conodusine E (5) had MS and NMR data that were identical to those of (-)-ervatamine I, recently isolated from Ervatamia hainanensis. Establishment of the absolute configuration of (+)-conodusine E (5) was based on analysis of the ECD data, correlation with (-)-heyneanine, and X-ray analysis, which showed that (+)-5 belongs to the same enantiomeric series as exemplified by (-)-coronaridine. The configuration at C-20' of the previously reported Tabernaemontana bisindole alkaloid 19'-oxotabernamine (renamed tabernamidine B) required revision based on the present results. Several of the bisindoles showed pronounced in vitro growth inhibitory activity against drug-sensitive and vincristine-resistant KB cells.
SRJ09, a promising anticancer drug lead: Elucidation of mechanisms of antiproliferative and apoptogenic effects and assessment of in vivo antitumor efficacy

Wong CC, Lim SH, Sagineedu SR, Lajis NH, Stanslas J

Pharmacol Res, 2016 05;107:66-78.
PMID: 26940565 DOI: 10.1016/j.phrs.2016.02.024

SRJ09 (3,19-(2-bromobenzylidene)andrographolide), a semisynthetic andrographolide (AGP) derivative, was shown to induce G1 cell cycle arrest and eventually apoptosis in breast and colon cancer cell lines. The present investigation was carried out to elucidate the mechanisms cell cycle arrest and apoptosis and evaluate the in vivo antitumor activity of SRJ09. The in vitro growth inhibitory properties of compounds were assessed in colon (HCT-116) and breast (MCF-7) cancer cell lines. Immunoblotting was utilized to quantitate the protein levels in cells. The gene expressions were determined using reverse transcriptase PCR (RT-PCR). Pharmacokinetic investigation was carried out by determining SRJ09 levels in plasma of Balb/C mice using HPLC. In vivo antitumor activity was evaluated in athymic mice carrying HCT-116 colon tumor xenografts. SRJ09 displayed improved in vitro activity when compared with AGP by producing rapid cell killing effect in vitro. Its activity was not compromised in MES-SA/Dx5 multidrug resistant (MDR) cells expressing p-glycoprotein. Cells treated with SRJ09 (0.1-10μM) displayed increased p21 protein level, which corresponded with gene expression. Whereas CDK4 protein level and gene expression was suppressed. The treatment did not affect cyclin D1. Changes of these proteins paralleled G1 cell cycle arrest in both cell lines as determined by flow cytometry. Induction of apoptosis by SRJ09 in HCT-116 cells which occurred independent of p53 and bcl-2 was inhibited in the presence of caspase 8 inhibitor, implicating the extrinsic apoptotic pathway. A single dose (100mg/kg, i.p) of SRJ09 produced a plasma concentration range of 12-30.4μM. At 400mg/kg (q4dX3), it significantly retarded growth of tumor xenografts. The antitumor activity of SRJ09 is suggested mediated via the induction of p21 expression and suppression of CDK-4 expression without affecting cyclin D1 to trigger G1 arrest leading to apoptosis.
Suboptimal HIV Testing Uptake Among Men Who Engage in Commercial Sex Work with Men in Asia

Jin H, Friedman MR, Lim SH, Guadamuz TE, Wei C

LGBT Health, 2016 Dec;3(6):465-471.
PMID: 26982598

PURPOSE: Men who have sex with men and are sex workers (MSMSW) are disproportionately affected by the growing and emerging HIV epidemic. As sex work and same-sex behavior are heavily stigmatized and often illegal in most Asian countries, HIV research focusing on MSMSW has been limited. The goal of this analysis is to examine HIV testing practices and identify correlates of HIV testing among MSMSW in Asia.
METHODS: The Asia Internet MSM Sex Survey, an online cross-sectional survey of 10,861 men who have sex with men (MSM), was conducted in 2010. Data on sociodemographic characteristics, HIV testing behaviors, and sexual behaviors were collected. Five hundred and seventy-four HIV-negative/unknown respondents reported receiving payment for sex with men at least once in the past 6 months and were included in this analysis. Multivariable logistic regression was conducted to identify independent correlates of HIV testing in the past year.
RESULTS: About half (48.6%) of the participants had been tested for HIV at least once within the past year, and 30.5% had never been tested. We also found that MSMSW participants who engaged in risky behaviors were less likely to be tested.
CONCLUSION: While one might expect a high HIV testing rate among MSMSW due to the risks associated with engaging in sex work, we found that HIV testing uptake is suboptimal among MSMSW in Asia. These results suggest that targeted HIV prevention and testing promotion among MSMSW are needed.
Arborisidine and Arbornamine, Two Monoterpenoid Indole Alkaloids with New Polycyclic Carbon-Nitrogen Skeletons Derived from a Common Pericine Precursor

Wong SP, Chong KW, Lim KH, Lim SH, Low YY, Kam TS

Org. Lett., 2016 Apr 1;18(7):1618-21.
PMID: 27033525 DOI: 10.1021/acs.orglett.6b00478

Two new monoterpene indole alkaloids, characterized by previously unencountered natural product skeletons, viz., arborisidine (1), incorporating indolizidine and cyclohexanone moieties fused to an indole unit, and arbornamine (2), incorporating an unprecedented 6/5/6/5/6 "arbornane" skeleton (distinct from the eburnan or tacaman skeleton), were isolated from a Malayan Kopsia arborea. The structures of the alkaloids were determined based on analysis of the NMR and MS data. Possible biogenetic pathways to these alkaloids from a common pericine precursor (3) are presented.
Vobatensines A-F, Cytotoxic Iboga-Vobasine Bisindoles from Tabernaemontana corymbosa

Sim DS, Teoh WY, Sim KS, Lim SH, Thomas NF, Low YY, et al.

J Nat Prod, 2016 Apr 22;79(4):1048-55.
PMID: 26918761 DOI: 10.1021/acs.jnatprod.5b01117

Six new bisindole alkaloids of the iboga-vobasine type, vobatensines A-F (1-6), in addition to four known bisindoles (8-11), were isolated from a stem bark extract of a Malayan Tabernaemontana corymbosa. The structures of these alkaloids were determined based on analysis of the spectroscopic data and in the case of vobatensines A (1), B (2), and 16'-decarbomethoxyvoacamine (8) also confirmed by partial syntheses. Nine of these alkaloids (1-5, 8-11) showed pronounced in vitro growth inhibitory activity against human KB, PC-3, LNCaP, HCT 116, HT-29, MCF7, MDA-MB-231, and A549 cancer cells.
Fulltext Young, Online and in the Dark: Scaling Up HIV Testing among MSM in ASEAN

Guadamuz TE, Cheung DH, Wei C, Koe S, Lim SH

PLoS One, 2015;10(5):e0126658.
PMID: 25973907 DOI: 10.1371/journal.pone.0126658

BACKGROUND: Poor HIV testing uptake by MSM may be attributable to unique challenges that are localized in Southeast Asia.
OBJECTIVE: To characterize MSM who never tested for HIV, to identify correlates of never testing, and to elucidate the perceived barriers to HIV testing.
METHODS: The present study used data from the Asian Internet MSM Sex Survey (AIMSS) and restricted the analysis to 4,310 MSM from the ten member countries of the Association of South East Asian Nations (ASEAN).
RESULTS: Among MSM participants from ASEAN in our sample, 1290 (29.9%) reported having never been tested for HIV, 471 (10.9%) tested for HIV more than 2 years ago, and 2186 (50.7%) reported their last test date was between 6 months and two years ago, with only 363 (8.4%) of these men having been tested in the past 6 months. In multivariable logistic regression, younger MSM (age 15-22 years old [AOR: 4.60, 95% CI: 3.04-6.96]), MSM with lower education (secondary school or lower [AOR: 1.37, 95% CI: 1.03-1.83]), MSM who identify as bisexual or heterosexual (compared to gay-identified) (AOR: 1.94, 95% CI: 1.60-2.35), and MSM who had never used a condom with male partners (AOR: 1.61, 95% CI: 1.32-1.97) had higher odds of never been HIV tested. Main reason for not being tested was a low risk perception of HIV exposure (n = 390, 30.2%).
CONCLUSION: Current HIV prevention response must not leave MSM "in the dark," but instead meet them where they are by utilizing the Internet creatively through social media and smart phones. As ASEAN Economic Community (AEC) is quickly becoming a reality, so must there be an equally fast and united response to slowing down the HIV epidemics among MSM in ASEAN.
Correlates of anal sex roles among Malay and Chinese MSM in Kuala Lumpur, Malaysia

Dangerfield DT, Gravitt P, Rompalo AM, Tai R, Lim SH

Int J STD AIDS, 2016 Mar;27(4):313-20.
PMID: 25887064 DOI: 10.1177/0956462415581125

Identifying roles for anal sex is an important issue for populations of MSM. We describe the prevalence of identifying as being 'top', 'bottom', 'versatile', or 'don't know/not applicable' among Malay and Chinese MSM in Kuala Lumpur, Malaysia, and behavioural outcomes according to these labels for sexual role identity. Data analysis was conducted on a survey administered during weekly outreach throughout Kuala Lumpur in 2012. Pearson's Chi square tests were used to compare demographic and behavioural characteristics of MSM who reported roles for anal sex. Binary logistic regression was used to explore the odds of behavioural outcomes among MSM who identified as 'bottom', 'versatile,' and 'don't know' compared to MSM who reported that 'top' was their sexual role. Labels for anal sex roles were significantly associated with condom use for last anal sex. Among MSM who used labels for anal sex roles, MSM who identified as 'bottom' had highest level of not using condoms for last anal sex (24.1%, p = .045). In binary logistic regression model, identifying as 'top' was significantly associated with reporting using a condom during last anal sex and reported consistent condom use for anal sex in the past six months (p = .039 and .017, respectively). With regard to sexual role identity, some MSM may be a part of a special subgroup of at-risk men to be targeted. Future research should evaluate the origins, meanings, and perceptions of these labels, and the developmental process of how these MSM identify with any of these categories. Research should also uncover condom use decision making with regard to these labels for sexual positioning.

Filters

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

External Links