MyMedR

Fulltext Development and Validation of a Coping Scale for Caregivers in Malaysia

Ibrahim N, Ong HC, Wahab S

Malays J Med Sci, 2017 May;24(3):83-91.

PMID: 28814936 MyJurnal DOI: 10.21315/mjms2017.24.3.10

INTRODUCTION: Caregivers often experience stressful situations while in the midst of the caregiving process. Thus, various methods of coping have been widely applied and studied in previous researches. The aim of this study was to develop a novel questionnaire to assess the coping strategies employed by those who provide care to patients, and to further validate it among caregivers of schizophrenia patients in Malaysia.

METHODS: This study, which involved the caregivers of schizophrenia patients from a hospital in Kuala Lumpur, Malaysia, was comprised of three parts, namely in-depth interviews, a pilot study, and the validation of the developed questionnaire, known as Caregiver Cope (CgCopeTM).

RESULTS: Part A originally consisted of eight themes, and it was later modified to seven themes with four items each after discussions with some experts. Part B initially had 28 items derived from the seven themes in Part A, which were then reduced to six components after a factor analysis. Part C of the questionnaire consisted of 19 items, with six components (Distraction, Caring for patient, Venting, Religion, Recreation, and Social support) having a moderate to high reliability ranging from a Cronbach's alpha coefficient of 0.54 to 0.82. A factor analysis showed that the six factors of coping accounted for 62.36% of the total variance.

CONCLUSION: The CgCOPETM questionnaire is suitable for use among caregivers of schizophrenia patients. There is a need to further validate the instrument among caregivers of other patient populations.

Extraction of natural astaxanthin from Haematococcus pluvialis using liquid biphasic flotation system

Khoo KS, Chew KW, Ooi CW, Ong HC, Ling TC, Show PL

Bioresour Technol, 2019 Oct;290:121794.

PMID: 31319214 DOI: 10.1016/j.biortech.2019.121794

This work aimed to study the application of liquid biphasic flotation (LBF) for the efficient and rapid recovery of astaxanthin from H. pluvialis microalgae. The performance of LBF for the extraction of astaxanthin was studied comprehensively under different operating conditions, including types and concentrations of food-grade alcohol and salt, volume ratio, addition of neutral salt, flotation period, and mass of dried H. pluvialis biomass powder. The maximum recovery, extraction efficiency and partition coefficient of astaxanthin obtained from the optimum LBF system were 95.11 ± 1.35%, 99.84 ± 0.05% and 385.16 ± 3.87, respectively. A scaled-up LBF system was also performed, demonstrating the feasibility of extracting natural astaxanthin from microalgae at a larger scale. This exploration of LBF system opens a promising avenue to the extraction of astaxanthin at lower cost and shorter processing time.

Fulltext Use of Composite Outcomes in Neonatal Trials: An Analysis of the Cochrane Reviews

Lai NM, Yap AQY, Ong HC, Wai SX, Yeo JHH, Koo CYE, et al.

Neonatology, 2021;118(3):259-263.

PMID: 33780936 DOI: 10.1159/000514402

INTRODUCTION: Composite outcomes are used to increase the power of a study by combining event rates. Many composite outcomes in adult clinical trials have components that differ substantially in patient importance, event rate, and effect size, making interpretation challenging. Little is known about the use of composite outcomes in neonatal randomized controlled trials (RCTs).

METHODS: We assessed the use of composite outcomes in neonatal RCTs included in Cochrane Neonatal reviews published till November 2017. Two authors reviewed the components of the composite outcomes to compare their patient importance and computed the ratios of effect sizes and event rates between the components, with an a priori threshold of 1.5, indicating a substantial difference. Descriptive statistics were presented.

RESULTS: We extracted 7,766 outcomes in 2,134 RCTs in 312 systematic reviews. Among them, 55 composite outcomes (0.7%) were identified in 46 RCTs. The vast majority (92.7%) of composite outcomes had 2 components, with death being the most common component (included 51 times [92.7%]). The components in nearly three-quarters of the composite outcomes (n = 40 [72.7%]) had different patient importance, while the effect sizes and event rates differed substantially between the components in 27 (49.1%) and 35 (63.6%) outcomes, respectively, with up to 43-fold difference in the event rates observed.

CONCLUSIONS: The majority of composite outcomes in neonatal RCTs had different patient importance with contrasting effect sizes and event rates between the components. In patient communication, clinicians should highlight individual components, rather than the composites, with explanation on the relationship between the components, to avoid misleading impression on the effect of the intervention. Future trials should report the estimates of all individual components alongside the composite outcomes presented.

Engineered macroalgal and microalgal adsorbents: Synthesis routes and adsorptive performance on hazardous water contaminants

Lee XJ, Ong HC, Ooi J, Yu KL, Tham TC, Chen WH, et al.

J Hazard Mater, 2022 Feb 05;423(Pt A):126921.

PMID: 34523506 DOI: 10.1016/j.jhazmat.2021.126921

Colourants, micropollutants and heavy metals are regarded as the most notorious hazardous contaminants found in rivers, oceans and sewage treatment plants, with detrimental impacts on human health and environment. In recent development, algal biomass showed great potential for the synthesis of engineered algal adsorbents suitable for the adsorptive management of various pollutants. This review presents comprehensive investigations on the engineered synthesis routes focusing mainly on mechanical, thermochemical and activation processes to produce algal adsorbents. The adsorptive performances of engineered algal adsorbents are assessed in accordance with different categories of hazardous pollutants as well as in terms of their experimental and modelled adsorption capacities. Due to the unique physicochemical properties of macroalgae and microalgae in their adsorbent forms, the adsorption of hazardous pollutants was found to be highly effective, which involved different mechanisms such as physisorption, chemisorption, ion-exchange, complexation and others depending on the types of pollutants. Overall, both macroalgae and microalgae not only can be tailored into different forms of adsorbents based on the applications, their adsorption capacities are also far more superior compared to the conventional adsorbents.

An evaluation of thermal characteristics of bacterium Actinobacillus succinogenes for energy use and circular bioeconomy

Lin BJ, Chen WH, Lin YY, Chang JS, Farooq A, Singh Y, et al.

Bioresour Technol, 2020 Apr;301:122774.

PMID: 31954973 DOI: 10.1016/j.biortech.2020.122774

The thermal characteristics of Actinobacillus succinogenes (AS) from pyrolysis, torrefaction, and combustion are analyzed to evaluate the potential of this biomass as a renewable fuel. AS pyrolysis can be classified into four stages, and its main decomposition zone is at 200-500 °C. The solid yield of AS after 60 min torrefaction is over 60 wt%, and the torrefaction severity index map indicates that a high torrefaction temperature with a short duration has a more profound influence on its decomposition. The Py-GC/MS analysis of AS suggests that the volatile products from 500 °C pyrolysis are similar to microalgae-derived pyrolysis bio-oils. The combustibility index (S) of AS is 4.07 × 10-7 which is much higher than that of lignite coal (0.39 × 10-7) and bituminous coal (0.18 × 10-7), and close to those of biochar and bio-oil. The obtained results are conducive to the development of microorganisms as fuel to achieve a circular bioeconomy.

Physicochemical property enhancement of biodiesel synthesis from hybrid feedstocks of waste cooking vegetable oil and Beauty leaf oil through optimized alkaline-catalysed transesterification

Milano J, Ong HC, Masjuki HH, Silitonga AS, Kusumo F, Dharma S, et al.

Waste Manag, 2018 Oct;80:435-449.

PMID: 30455026 DOI: 10.1016/j.wasman.2018.09.005

Recycling waste cooking vegetable oils by reclaiming and using these oils as biodiesel feedstocks is one of the promising solutions to address global energy demands. However, producing these biodiesels poses a significant challenge because of their poor physicochemical properties due the high free fatty acid content and impurities present in the feedstock, which will reduce the biodiesel yields. Hence, this study implemented the following strategy in order to address this issue: (1) 70 vol% of waste cooking vegetable oil blended with 30 vol% of Calophyllum inophyllum oil named as WC70CI30 used to alter its properties, (2) a three-stage process (degumming, esterification, and transesterification) was conducted which reduces the free fatty acid content and presence of impurities, and (3) the transesterification process parameters (methanol/oil ratio, reaction temperature, reaction time, and catalyst concentration) were optimized using response surface methodology in order to increase the biodiesel conversion yield. The results show that the WC70CI30 biodiesel has favourable physicochemical properties, good cold flow properties, and high oxidation stability (22.4 h), which fulfil the fuel specifications stated in the ASTM D6751 and EN 14214 standards. It found that the WC70CI30 biodiesel has great potential as a diesel substitute without the need for antioxidants and pour point depressants.

Source, distribution and emerging threat of micro- and nanoplastics to marine organism and human health: Socio-economic impact and management strategies

Mofijur M, Ahmed SF, Rahman SMA, Arafat Siddiki SY, Islam ABMS, Shahabuddin M, et al.

Environ Res, 2021 04;195:110857.

PMID: 33581088 DOI: 10.1016/j.envres.2021.110857

The nature of micro- and nanoplastics and their harmful consequences has drawn significant attention in recent years in the context of environmental protection. Therefore, this paper aims to provide an overview of the existing literature related to this evolving subject, focusing on the documented human health and marine environment impacts of micro- and nanoplastics and including a discussion of the economic challenges and strategies to mitigate this waste problem. The study highlights the micro- and nanoplastics distribution across various trophic levels of the food web, and in different organs in infected animals which is possible due to their reduced size and their lightweight, multi-coloured and abundant features. Consequently, micro- and nanoplastics pose significant risks to marine organisms and human health in the form of cytotoxicity, acute reactions, and undesirable immune responses. They affect several sectors including aquaculture, agriculture, fisheries, transportation, industrial sectors, power generation, tourism, and local authorities causing considerable economic losses. This can be minimised by identifying key sources of environmental plastic contamination and educating the public, thus reducing the transfer of micro- and nanoplastics into the environment. Furthermore, the exploitation of the potential of microorganisms, particularly those from marine origins that can degrade plastics, could offer an enhanced and environmentally sound approach to mitigate micro- and nanoplastics pollution.

Fulltext Backcalculation of HIV infection rates in Malaysia

Ong HC, Soo KL

Med J Malaysia, 2006 Dec;61(5):616-20.

PMID: 17623964 MyJurnal

It has been almost two decades ago since the first AIDS case was reported in Malaysia. It has also been approximately eight years ago when the method of backcalculation was used to estimate the past HIV infection rate from the AIDS incidence data and an estimate of the incubation period distribution. This method is used because it makes use of the Malaysian AIDS incidence which is fairly reliable and reflects the trend of the epidemic as compared to the HIV infection rate recorded. The latest results generated show a slowdown in the increase of the number of estimated infected HIV+ cases in the late 1990s and this trend is supported by a slowdown in the increase of the number of AIDS cases recorded.

Fulltext A control chart based on cluster-regression adjustment for retrospective monitoring of individual characteristics

Ong HC, Alih E

PLoS One, 2015;10(4):e0125835.

PMID: 25923739 DOI: 10.1371/journal.pone.0125835

The tendency for experimental and industrial variables to include a certain proportion of outliers has become a rule rather than an exception. These clusters of outliers, if left undetected, have the capability to distort the mean and the covariance matrix of the Hotelling's T2 multivariate control charts constructed to monitor individual quality characteristics. The effect of this distortion is that the control chart constructed from it becomes unreliable as it exhibits masking and swamping, a phenomenon in which an out-of-control process is erroneously declared as an in-control process or an in-control process is erroneously declared as out-of-control process. To handle these problems, this article proposes a control chart that is based on cluster-regression adjustment for retrospective monitoring of individual quality characteristics in a multivariate setting. The performance of the proposed method is investigated through Monte Carlo simulation experiments and historical datasets. Results obtained indicate that the proposed method is an improvement over the state-of-art methods in terms of outlier detection as well as keeping masking and swamping rate under control.

Fulltext An application of the backcalculation method to estimate past HIV infection rates in Malaysia

Ong HC, Quah SH, Low HC

Med J Malaysia, 1998 Dec;53(4):385-91.

PMID: 10971982

The method of backcalculation estimates past HIV infection rates from available AIDS incidence data and an estimate of the incubation period. The method is used on the Malaysian data to model the AIDS epidemic because it makes use of the Malaysian AIDS incidence data which is fairly reliable and is more reflective of the trend of the epidemic as compared to the HIV infection rate recorded. An application is made on the monthly AIDS incidence data in Malaysia from January 1995 until August 1996 released by the Ministry of Health, Malaysia using the backcalculation program from Bacchetti et al and the incubation period distribution from Brookmeyer to generate the current HIV infection rate for Malaysia (until August 1996).

Fulltext Towards better perinatal health

Ong HC

Med J Malaysia, 1983 Sep;38(3):176-7.

PMID: 6672555

A case of primary adenocarcinoma of the fallopian tube

Ong HC, Chan WF, Sinnathuray TA

Med J Malaysia, 1978 Mar;32(3):217-9.

PMID: 683046

Anencephalic pregnancies in a Malaysian hospital

Ong HC, Singh H, Ng TK, Chong CH

Med J Malaysia, 1978 Mar;32(3):212-4.

PMID: 683044

Human placental lactogen physiological role in pregnancy

Ong HC

Med J Malaysia, 1976 Mar;30(3):165-7.

PMID: 958050

Brow presentation

Ong HC, Chelvam P

Med J Malaysia, 1975 Jun;29(4):299-301.

PMID: 1196178

Anaemia in pregnancy in an aboriginal population

Ong HC

J Trop Med Hyg, 1974 Jan;77(1):22-6.

PMID: 4811560

Fulltext Case report : Actinomyces naeslundii complicating preterm labour in a trisomy-21 pregnancy

Ong HC, Ling AC, Ng DS, Ng RX, Wong PL, Omar SFS

IDCases, 2021;23:e01051.

PMID: 33532241 DOI: 10.1016/j.idcr.2021.e01051

Preterm birth is a global concern with considerable morbidity and mortality. Intrapartum infection is a known cause of preterm birth and Actinomyces infection is one of the infections contributing to preterm birth. We report a case of preterm birth of a trisomy-21 neonate to a mother with positive Actinomyces naeslundii from an intra-operative placental swab sample and discussed the relationship of this bacteria and preterm delivery, and the role of postpartum antibiotics use in this case.

Migration in Malaysian aborigines: clinical observations in pregnancy

Ong HC

Southeast Asian J. Trop. Med. Public Health, 1975 Sep;6(3):407-412.

PMID: 1221499

This study presents clinical observations in pregnancy made on aborigines of the deep jungle and "outside" populations. Migration out of the jungle results in lowered nutritional status as a result of low socio-economic status in the "outside" aborigine. This, together with food habits, increased family size and higher incidence of helminthic infestations, results in lower mean values of Hb, PVC and MCHC and a higher prevalence of anaemia in pregnancy in the migrant aborigine. A higher population density in the "outside" population resulting in frequent intermingling and increased chances of cross-contamination probably explains the increased vaginal bacterial growth in the "outside" Aborigine women. A higher prevalence of vaginal candidiasis in the "outside" aborigine woman is probably related to exposure to oral contraceptives and broad-spectrum antibiotics. On the other hand, better medical and obstetrical services become more readily available to the "outside" aborigine and this results in a favourable influence on perinatal health.

Partial exchange transfusion in the treatment of severe anaemia in late pregnancy

Ong HC, Chan WF, Hussein N

Med J Malaysia, 1975 Sep;30(1):63-65.

PMID: 1207535

Face presentation

Ong HC, Teo SP

Med J Malaysia, 1976 Sep;31(1):42-5.

PMID: 1023012

Displaying publications 21 - 40 of 73 in total