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Fulltext Traumatic floating clavicle: a case report

Choo C, Wong H, Nordin A

Malays Orthop J, 2012 Nov;6(3):57-9.
PMID: 25279061 MyJurnal DOI: 10.5704/MOJ.1207.008

Shoulder girdle injuries after high energy traumatic impacts to the shoulder have been well documented. Based on the series of 1603 injuries of the shoulder girdle reported by Cave and colleagues, 85% of the dislocations were glenohumeral, 12% acromioclavicular and 3% sternoclavicular (1). Less frequently described are injuries involving both the sternoclavicular and acromioclavicular joints simultaneously in one extremity. The present report discusses a case of traumatic floating clavicle associated with ipsilateral forearm and wrist injury which was treated surgically.
Fulltext Editorial: Owning a Body + Moving a Body = Me?

Pia L, Garbarini F, Kalckert A, Wong HY

Front Hum Neurosci, 2019;13:88.
PMID: 30936826 DOI: 10.3389/fnhum.2019.00088
"I suppose in our culture, old means no sex": PLWH and healthcare provider views on factors influencing late HIV testing and diagnosis among older adults in Malaysia

Wong HY, Rajasuriar R, Wong PL, Lee YK

AIDS Care, 2024 Mar 25.
PMID: 38526987 DOI: 10.1080/09540121.2024.2331220

The proportion of new HIV diagnoses among older adults aged ≥50 years continues to rise. Older adults are at higher risk of late diagnosis which is associated with higher treatment complexity and poorer health outcomes. Few studies in the Asia-Pacific region have explored factors contributing to late presentation and diagnosis in this population. Thus, our study aimed to explore factors influencing late HIV diagnosis among older adults ≥50 years in Malaysia. We conducted in-depth interviews with 16 older adults newly diagnosed with HIV (OPLWH) and focus group discussions with seven healthcare providers (HCPs) from different specialties in an academic tertiary hospital in Malaysia. All sessions were audio-recorded, transcribed verbatim and analysed thematically. Three main themes related to late diagnosis among OPLWH emerged: (1) challenge in recognizing HIV symptoms among older persons, (2) older persons and HCPs having low index of suspicion of HIV and (3) poor acceptance of HIV testing among older persons due to perceived personal and social identities. HCPs often missed HIV symptoms and these collectively culminated in OPLWH experiencing complex diagnostic journeys resulting in late HIV diagnosis. To reduce delays in HIV diagnosis, strategies are needed to improve HIV knowledge and risk perception among both older adults and HCPs.
Scattering noise estimation of range-gated imaging system in turbid condition

Tan C, Seet G, Sluzek A, Wang X, Yuen CT, Fam CY, et al.

Opt Express, 2010 Sep 27;18(20):21147-54.
PMID: 20941011 DOI: 10.1364/OE.18.021147

The range-gated imaging systems are reliable underwater imaging system with the capability to minimize backscattering effect from turbid media. The tail-gating technique has been developed to fine tune the signal to backscattering ratio and hence improve the gated image quality. However, the tail-gating technique has limited image quality enhancement in high turbidity levels. In this paper, we developed a numerical model of range-gated underwater imaging system for near target in turbid medium. The simulation results matched the experimental work favorably. Further investigation using this numerical model shows that the multiple scattering components of the backscattering noise dominate for propagation length larger than 4.2 Attenuation Length (AL). This has limited the enhancement of tail-gating technique in high turbidity conditions.
Fulltext Performance Analysis of a Defected Ground-Structured Antenna Loaded with Stub-Slot for 5G Communication

Rahman MM, Islam MS, Wong HY, Alam T, Islam MT

Sensors (Basel), 2019 Jun 10;19(11).
PMID: 31185676 DOI: 10.3390/s19112634

In this paper, a defected ground-structured antenna with a stub-slot configuration is proposed for future 5G wireless applications. A simple stub-slot configuration is used in the patch antenna to get the dual band frequency response in the 5G mid-band and the upper unlicensed frequency region. Further, a 2-D double period Electronic band gap (EBG) structure has been implemented as a defect in the metallic ground plane to get a wider impedance bandwidth. The size of the slots and their positions are optimized to get a considerably high impedance bandwidth of 12.49% and 4.49% at a passband frequency of 3.532 GHz and 6.835 GHz, respectively. The simulated and measured realized gain and reflection coefficients are in good agreement for both operating bandwidths. The overall antenna structure size is 33.5 mm × 33.5 mm. The antenna is fabricated and compared with experimental results. The proposed antenna shows a stable radiation pattern and high realized gain with wide impedance bandwidth using the EBG structure, which are necessary for the requirements of IoT applications offered by 5G technology.
Fulltext The mobile-phone-based iCOTM Smokerlyzer®: Comparison with the piCO+ Smokerlyzer® among smokers undergoing methadone-maintained therapy

Wong HY, Subramaniyan M, Bullen C, Amer Siddiq AN, Danaee M, Yee A

Tob Induc Dis, 2019;17:65.
PMID: 31582954 DOI: 10.18332/tid/111355

INTRODUCTION: The mobile-phone-based Bedfont iCOTM Smokerlyzer® is of unknown validity and reproducibility compared to the widely-used piCO+ Smokerlyzer®. We aimed to compare the validity and reproducibility of the iCOTM Smokerlyzer® with the piCO+ Smokerlyzer® among patients reducing or quitting tobacco smoking.
METHODS: Methadone-maintained therapy (MMT) users from three centers in Malaysia had their exhaled carbon monoxide (eCO) levels recorded via the piCO+ and iCOTM Smokerlyzers®, their nicotine dependence assessed with the Malay version of the Fagerström Test for Nicotine Dependence (FTND-M), and daily tobacco intake measured via the Opiate Treatment Index (OTI) Tobacco Q-score. Pearson partial correlations were used to compare the eCO results of both devices, as well as the corresponding FTND-M scores.
RESULTS: Among the 146 participants (mean age 47.9 years, 92.5% male, and 73.3% Malay ethnic group) most (55.5%) were moderate smokers (6-19 cigarettes/day). Mean eCO categories were significantly correlated between both devices (r=0.861, p<0.001), and the first and second readings were significantly correlated for each device (r=0.94 for the piCO+ Smokerlyzer®, p<0.001; r=0.91 for the iCOTM Smokerlyzer®, p<0.001). Exhaled CO correlated positively with FTND-M scores for both devices. The post hoc analysis revealed a significantly lower iCOTM Smokerlyzer® reading of 0.82 (95% CI: 0.69-0.94, p<0.001) compared to that of the piCO+ Smokerlyzer®, and a significant intercept of -0.34 (95% CI: -0.61 - -0.07, p=0.016) on linear regression analysis, suggesting that there may be a calibration error in one or more of the iCOTM Smokerlyzer® devices.
CONCLUSIONS: The iCOTM Smokerlyzer® readings are highly reproducible compared to those of the piCO+ Smokerlyzer®, but calibration guidelines are required for the mobile-phone-based device. Further research is required to assess interchangeability.
Fulltext A New Association Of Guillain Barre Syndrome In A Patient With Central Nervous System Melioidosis

Koh EJ, Tan KN, Chan ZW, Candice Wong HY, Chin ML, Lee TC

J Ayub Med Coll Abbottabad, 2023;35(2):334-336.
PMID: 37422834 DOI: 10.55519/JAMC-02-11470

Burkholderia pseudomallei affecting the central nervous system has been extensively reported in the literature. However, combined central nervous system and peripheral nervous system involvement in melioidosis has never been reported. We report a 66-year-old man with diabetes mellitus who was diagnosed to have central nervous system melioidosis and developed acute flaccid quadriplegia. Nerve conduction studies and anti-ganglioside antibodies were consistent with Guillain-Barre syndrome. This case report highlights the importance to recognise the possibility of Guillain Barre syndrome complicating central nervous system melioidosis and stresses the urgency of early consideration of this complication, as early immunomodulatory therapy may hasten neurological recovery.
Sequence polymorphism of the mitochondrial DNA hypervariable regions I and II in 205 Singapore Malays

Wong HY, Tang JS, Budowle B, Allard MW, Syn CK, Tan-Siew WF, et al.

Leg Med (Tokyo), 2007 Jan;9(1):33-7.
PMID: 17150401

Mitochondrial DNA sequences of the hypervariable regions HV1 and HV2 were analyzed in 205 unrelated ethnic Malays residing in Singapore as an initial effort to generate a database for forensic identification purposes. Sequence polymorphism was detected using PCR and direct sequencing analysis. A total of 152 haplotypes was found containing 152 polymorphisms. Out of the 152 haplotypes, 115 were observed only once and 37 types were seen in multiple individuals. The most common haplotype (16223T, 16295T, 16362C, 73G, 146C, 199C, 263G, and 315.1C) was shared by 7 (3.41%) individuals, two haplotypes were shared by 4 individuals, seven haplotypes were shared by 3 individuals, and 27 haplotypes by 2 individuals. Haplotype diversity and random match probability were estimated to be 0.9961% and 0.87%, respectively.
Fulltext Metamaterial Cell-Based Superstrate towards Bandwidth and Gain Enhancement of Quad-Band CPW-Fed Antenna for Wireless Applications

Al-Bawri SS, Islam MS, Wong HY, Jamlos MF, Narbudowicz A, Jusoh M, et al.

Sensors (Basel), 2020 Jan 14;20(2).
PMID: 31947533 DOI: 10.3390/s20020457

A multiband coplanar waveguide (CPW)-fed antenna loaded with metamaterial unit cell for GSM900, WLAN, LTE-A, and 5G Wi-Fi applications is presented in this paper. The proposed metamaterial structure is a combination of various symmetric split-ring resonators (SSRR) and its characteristics were investigated for two major axes directions at (x and y-axis) wave propagation through the material. For x-axis wave propagation, it indicates a wide range of negative refractive index in the frequency span of 2-8.5 GHz. For y-axis wave propagation, it shows more than 2 GHz bandwidth of near-zero refractive index (NZRI) property. Two categories of the proposed metamaterial plane were applied to enhance the bandwidth and gain. The measured reflection coefficient (S11) demonstrated significant bandwidths increase at the upper bands by 4.92-6.49 GHz and 3.251-4.324 GHz, considered as a rise of 71.4% and 168%, respectively, against the proposed antenna without using metamaterial. Besides being high bandwidth achieving, the proposed antenna radiates bi-directionally with 95% as the maximum radiation efficiency. Moreover, the maximum measured gain reaches 6.74 dBi by a 92.57% improvement compared with the antenna without using metamaterial. The simulation and measurement results of the proposed antenna show good agreement.
Fulltext Compact Ultra-Wideband Monopole Antenna Loaded with Metamaterial

Al-Bawri SS, Hwang Goh H, Islam MS, Wong HY, Jamlos MF, Narbudowicz A, et al.

Sensors (Basel), 2020 Jan 31;20(3).
PMID: 32024016 DOI: 10.3390/s20030796

A printed compact monopole antenna based on a single negative (SNG) metamaterial is proposed for ultra-wideband (UWB) applications. A low-profile, key-shaped structure forms the radiating monopole and is loaded with metamaterial unit cells with negative permittivity and more than 1.5 GHz bandwidth of near-zero refractive index (NZRI) property. The antenna offers a wide bandwidth from 3.08 to 14.1 GHz and an average gain of 4.54 dBi, with a peak gain of 6.12 dBi; this is in contrast to the poor performance when metamaterial is not used. Moreover, the maximum obtained radiation efficiency is 97%. A reasonable agreement between simulation and experiments is realized, demonstrating that the proposed antenna can operate over a wide bandwidth with symmetric split-ring resonator (SSRR) metamaterial structures and compact size of 14.5 × 22 mm2 (0.148 λ0 × 0.226 λ0) with respect to the lowest operating frequency.
Poor HIV-Related Outcomes in Older Adults Newly Diagnosed With HIV: A 4-Year Retrospective Analysis From a Single Site in Asia

Wong HY, Wong PL, Bador MK, Chong ML, Shenoi S, Rozanova J, et al.

J Acquir Immune Defic Syndr, 2023 May 01;93(1):64-72.
PMID: 36716735 DOI: 10.1097/QAI.0000000000003169

BACKGROUND: In resource-limited settings, HIV-related services are often targeted to younger key populations, although increasing reports have found that adults ≥50 years now account for among the highest increase in new HIV diagnosis. We assessed the proportion of new HIV infections among older adults (≥50 years) and compared their sociodemographics, risk behaviors, and HIV-related outcomes to newly diagnosed younger adults (<50 years).
METHODS: This retrospective analysis included all new HIV diagnosis from 2016 to 2019 at the University of Malaya Medical Centre, Malaysia. Trends of HIV diagnosis was assessed using join point regression analysis, and characteristics between the older and younger adults were compared using χ 2 test or Mann-Whitney U test. Kaplan-Meier analysis and log-rank test were used to compare the survival probability in both age groups.
RESULTS: From a total of 594 new HIV diagnosis between 2016 and 2019, 11.5% (N = 68) were among older adults with an annual percent increase of 5.50%. Older adults were more likely ethnic Indians ( P < 0.001), acquired HIV through heterosexual contact ( P = 0.001), had late presentation to care ( P = 0.003), and multimorbidity ( P < 0.001). Immunological responses after 12 months on antiretroviral therapy were comparable in both the groups. Older adults had a higher probability of death compared with younger adults (adjusted hazard ratio 1.81, 95% confidence interval: 1.02 to 3.23, P = 0.043) after adjusting for sex, mode of HIV transmission, late presentation to care, antiretroviral therapy initiation, and multimorbidity.
CONCLUSION: Older adults diagnosed with HIV were associated with late care presentation and increased mortality. There is an urgent need to enhance uptake of HIV testing and linkage to care among older individuals in our setting.