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Haemoglobin E variants and pregnancy in Malaysian aborigines

Ong HC

Acta Haematol., 1974;52(4):220-2.
PMID: 4217527 DOI: 10.1159/000208244

Haemoglobin E complicates 22.2°/o of pregnancy in Malaysian aborigines, the prevalence of variants associated with pregnancy being, 15.8% with Hb E trait abnormality, 3.9% with Hb E homozygous disease, and 2.5% with Hb E thalassaemia disease. Minor haematological abnormalities occur with the trait and homozygous conditions, though a more unfavourable response is expected with Hb E thalassaemia. Haemolysis is not a prominent feature and it is suggested that factors other than the haemoglobinopathic state
probably accounts for any unfavourable response in pregnancy.
Key Words: Haemoglobin E; Haemoglobinopathies; Haemolytic anaemias; Hb E thalassaemia; Malaysia; Pregnancy
Study site: Hospital Orang Asli, Gombak, Selangor, Malaysia
Hematological values in pregnancy in Orang Asli (aboriginal) women

Ong HC

Med J Malaysia, 1973 Jun;27(4):240-2.
PMID: 4270778
Mucinous cystadenoma, serous cystadenoma and benign cystic teratoma of the ovary: clinico-pathologic differences observed in a Malaysian hospital

Ong HC, Chan WF

Cancer, 1978 Apr;41(4):1538-42.
PMID: 639009

A study of 207 benign ovarian tumors seen at the University Hospital, Kuala Lumpur between 1968 and 1975 was made to evaluate the clinical features that might be useful in the preoperative differentiation of mucinous cystadenoma, serous cystadenoma, and cystic teratoma of the ovary. This study indicated that the pertinent information included the mean age of the patient, the marital and menstrual status, and the estimated tumor size. The racial background was an additional factor in serous cystadenoma. Features like parity, the location of the tumor, and ABO blood group pattern were of no value in the preoperative differentiation.
Haemoglobin H disease and pregnancy in a Malaysian woman

Ong HC, White JC, Sinnathuray TA

Acta Haematol., 1977;58(4):229-33.
PMID: 410224 DOI: 10.1159/000207832

A case of haemoglobin H (HbH) disease associated with pregnancy is presented and discussed in the light of reports in the literature. The variable symptomatology is commented upon, although mild to moderate chronic haemolytic anaemia seems to be a constant feature. The roles of folic acid supplements and of splenectomy; the avoidance of oxidant drugs, and the mode of inheritance in HbH disease are briefly commented upon. Available reports indicate that HbH disease probably has no adverse effect on pregnancy. However, the association of the two conditions is uncommon, and reports are too few, therefore, to allow definite conclusions on the outcome in all instances.
The ovaries at abdominal hysterectomy-conservation or removal?

Ong HC

Med J Malaysia, 1975 Sep;30(1):48-51.
PMID: 1207532
Obstetrical data in Malaysian aborigine women

Ong HC

Trop Geogr Med, 1974 Dec;26(4):384-8.
PMID: 4456697
An unusual case to pentastomiasis of the fallopian tube in an Aborigine woman

Ong HC

J Trop Med Hyg, 1974 Aug;77(8):187-9.
PMID: 4422640
Fulltext Psychological distress, perceived stigma, and coping among caregivers of patients with schizophrenia

Ong HC, Ibrahim N, Wahab S

Psychol Res Behav Manag, 2016;9:211-8.
PMID: 27574475 DOI: 10.2147/PRBM.S112129

Nowadays, family members are gradually taking on the role of full-time caregivers for patients suffering from schizophrenia. The increasing burden and tasks of caretaking can cause them psychological distress such as depression or anxiety. The aim of this study was to measure the correlation between perceived stigma and coping, and psychological distress as well as determine the predictors of psychological distress among the caregivers. Results showed that 31.5% of the caregivers experienced psychological distress. "Community rejection" was found to be positively associated with psychological distress. In case of coping subscales, psychological distress had a positive correlation with substance use, use of emotional support, behavioral disengagement, venting, and self-blame, while it was negatively correlated with "positive reframing". Behavioral disengagement was the best predictor of psychological distress among caregivers of patients with schizophrenia, followed by positive reframing, use of emotional support, self-blame, and venting. Health practitioners can use adaptive coping strategies instead of maladaptive for caregivers to help ease their distress and prevent further deterioration of psychological disorders.
Study site: Psychiatric Clinic, Hospital Canselor Tuanku Muhriz (Pusat Perubatan Universiti Kebangsaan Malaysia, PPUKM)
Scales & Questionnaire: Kessler’s K10
Psychological Distress Scale; Devaluation of Consumer Scale (DCS); Devaluation of Consumer Families Scale (DCFS); Brief COPE
Fulltext Pattern of heart disease and pregnancy seen in a Malaysian hospital

Ong HC, Puraviappan AP, Sinnathuray TA, Chong CH, Sen DK

Singapore Med J, 1978 Jun;19(2):93-7.
PMID: 751193

Pregnancy was associated with cardiac disease in 0.94% of pregnancies. 0.66% with rheumatic lesions and 0.25'\'0 with congenital lesions. The Malays had a higher incidence than the Chinese and Indians. Most of the cardiac pregnancies were in patients between 20-30 years of age and gravida 1 to 4. Nevertheless. still about 30% of cardiac pregnancies were in patients 30 years and over in age and 20% in patient gravida 5 and above. Rheumatic lesions predominated. involving mainly the mitral valve. of which the major lesion was mitral stenosis. PDA. ASD and VSD were the major congenital lesions. Major antepartum matemal complications included arrhythmias. heart failure, anemia and pre-eclampsia. Of the arrhythmias. atrial fibrillation and sinus tachycardia occurred most commonly. A high incidence of prophylactic forceps and vacuum deliveries
was evident. There was one matemal death. The majority of infants were bom alive and well.
Fulltext Clinical observations of hydatidiform moles in a Malaysian hospital

Ong HC, Lee PYA, Ng TK, Chong CH

Singapore Med J, 1978 Mar;19(1):33-6.
PMID: 663681

A retrospective analysis of 102 cases of hydatidiform moles seen in the Maternity Hospital, Kuala Lumpur, Malaysia, is presented. The incidence was 1 : 669. The tumour was more common In the Malays and in the lower social class patients. No specific age group or parity group was exempted. Vaginal bleeding and amenorrhoea were prominent features. Hyperemesis and abdominal cramps occurred less commonly. The uterine size was larger than dates in 62.7% of patients. Pre-eclampsia complicated 23.5% of the moles and Its severity was inversely related to the uterine size. Spontaneous abortion occurred In 57.8% of patients at a mean gestational period of 19 weeks.

Study site: Maternity Hospital Kuala
Lumpur, Malaysia
Fulltext A clinico-pathological review of benign cystic teratoma of the ovary

Ong HC, Chan WF

Singapore Med J, 1977 Jun;18(2):100-4.
PMID: 929220

Benign cystic teratoma of the ovary has a varied incidence, varying from 30 to 50 per cent of all benign ovarian tumours. This tumour tends to occur in the reproductive age group (20 to 40 years), and the majority of patients are married with children. About 40 per cent of patients are symptomless. Of those with symptoms, abdominal pain and mass are the commonest. Torsion is the most frequent complication encountered, and the presence of acute pain should make one suspect this complication. The tumour is bilateral in 10 to 20 per cent of patients. This high bilateral occurrence places a responsibility on the gynaecologist to inspect the opposite ovary in all cases of unilateral dermoid cyst of the ovary at the time of laparotomy. Germ·layer derivatives are predominantly ectodermal in origin, although both mesodermal and entodermal derivatives occur frequently.
Fulltext High performance liquid chromatography profiling of health-promoting phytochemicals and evaluation of antioxidant, anti-lipoxygenase, iron chelating and anti-glucosidase activities of wetland macrophytes

Ooh KF, Ong HC, Wong FC, Sit NW, Chai TT

Pharmacogn Mag, 2014 Aug;10(Suppl 3):S443-55.
PMID: 25298659 DOI: 10.4103/0973-1296.139767

The phytochemistry and bioactivity of wetland macrophytes are underexplored. Plants are known as the natural sources of phytochemical beneficial to health.
Synthesis, characteristics and sonocatalytic activities of calcined γ-Fe2O3 and TiO2 nanotubes/γ-Fe2O3 magnetic catalysts in the degradation of Orange G

Pang YL, Lim S, Ong HC, Chong WT

Ultrason Sonochem, 2016 Mar;29:317-27.
PMID: 26585012 DOI: 10.1016/j.ultsonch.2015.10.003

In this work, γ-Fe2O3 and TiO2 NTs/γ-Fe2O3 composites with good magnetism and sonocatalytic activity were prepared by a facile polyol method and utilize the principle of isoelectric point method, respectively. The structural and magnetic features of the prepared calcined γ-Fe2O3 and composite catalysts were investigated by transmission electron microscopy (TEM), powder X-ray diffraction (XRD), surface analysis, UV-Vis diffuse reflectance spectra (UV-Vis DRS), vibrating sample magnetometry (VSM) and zeta potential analysis. The effects of calcination temperature on γ-Fe2O3 phase variation, physical properties and sonocatalytic properties were investigated. The porosity, specific surface area, band gap energy and sonocatalytic activity of γ-Fe2O3 were gradually decreased with calcination temperature increased. TiO2 NTs/γ-Fe2O3 with appropriate composition and specific structural features possess synergetic effects such as efficient separation of charge carriers and hydroxyl radicals produced by heterogeneous fenton and fenton-like reactions. This enhanced the sonocatalytic activity for the degradation of Orange G under ultrasonic irradiation. The sonocatalytic reactions obeyed pseudo first-order kinetics. All these information provide insight into the design and development of high-efficiency catalyst for wastewater treatment.
Fulltext Effects of acids pre-treatment on the microbial fermentation process for bioethanol production from microalgae

Phwan CK, Chew KW, Sebayang AH, Ong HC, Ling TC, Malek MA, et al.

Biotechnol Biofuels, 2019;12:191.
PMID: 31384298 DOI: 10.1186/s13068-019-1533-5

Background: Microalgae are one of the promising feedstock that consists of high carbohydrate content which can be converted into bioethanol. Pre-treatment is one of the critical steps required to release fermentable sugars to be used in the microbial fermentation process. In this study, the reducing sugar concentration of Chlorella species was investigated by pre-treating the biomass with dilute sulfuric acid and acetic acid at different concentrations 1%, 3%, 5%, 7%, and 9% (v/v).
Results: 3,5-Dinitrosalicylic acid (DNS) method, FTIR, and GC-FID were employed to evaluate the reducing sugar concentration, functional groups of alcohol bonds and concentration of bioethanol, respectively. The two-way ANOVA results (p
Engine performance and emission characteristics of palm biodiesel blends with graphene oxide nanoplatelets and dimethyl carbonate additives

Razzaq L, Mujtaba MA, Soudagar MEM, Ahmed W, Fayaz H, Bashir S, et al.

J Environ Manage, 2021 Mar 15;282:111917.
PMID: 33453625 DOI: 10.1016/j.jenvman.2020.111917

This study investigated the engine performance and emission characteristics of biodiesel blends with combined Graphene oxide nanoplatelets (GNPs) and 10% v/v dimethyl carbonate (DMC) as fuel additives as well as analysed the tribological characteristics of those blends. 10% by volume DMC was mixed with 30% palm oil biodiesel blends with diesel. Three different concentrations (40, 80 and 120 ppm) of GNPs were added to these blends via the ultrasonication process to prepare the nanofuels. Sodium dodecyl sulphate (SDS) surfactant was added to improve the stability of these blends. GNPs were characterised using Scanning Electron Microscope (SEM) and Fourier Transform Infrared (FTIR), while the viscosity of nanofuels was investigated by rheometer. UV-spectrometry was used to determine the stability of these nanoplatelets. A ratio of 1:4 GNP: SDS was found to produce maximum stability in biodiesel. Performance and emissions characteristics of these nanofuels have been investigated in a four-stroke compression ignition engine. The maximum reduction in BSFC of 5.05% and the maximum BTE of 22.80% was for B30GNP40DMC10 compared to all other tested blends. A reduction in HC (25%) and CO (4.41%) were observed for B30DMC10, while a reduction in NOx of 3.65% was observed for B30GNP40DMC10. The diesel-biodiesel fuel blends with the addition of GNP exhibited a promising reduction in the average coefficient of friction 15.05%, 8.68% and 3.61% for 120, 80 and 40 ppm concentrations compared to B30. Thus, combined GNP and DMC showed excellent potential for utilisation in diesel engine operation.
Fourth generation biofuel from genetically modified algal biomass: Challenges and future directions

Shokravi H, Shokravi Z, Heidarrezaei M, Ong HC, Rahimian Koloor SS, Petrů M, et al.

Chemosphere, 2021 Dec;285:131535.
PMID: 34329137 DOI: 10.1016/j.chemosphere.2021.131535

Genetic engineering applications in the field of biofuel are rapidly expanding due to their potential to boost biomass productivity while lowering its cost and enhancing its quality. Recently, fourth-generation biofuel (FGB), which is biofuel obtained from genetically modified (GM) algae biomass, has gained considerable attention from academic and industrial communities. However, replacing fossil resources with FGB is still beset with many challenges. Most notably, technical aspects of genetic modification operations need to be more fully articulated and elaborated. However, relatively little attention has been paid to GM algal biomass. There is a limited number of reviews on the progress and challenges faced in the algal genetics of FGB. Therefore, the present review aims to fill this gap in the literature by recapitulating the findings of recent studies and achievements on safe and efficient genetic manipulation in the production of FGB. Then, the essential issues and parameters related to genome editing in algal strains are highlighted. Finally, the main challenges to FGB pertaining to the diffusion risk and regulatory frameworks are addressed. This review concluded that the technical and biosafety aspects of FGB, as well as the complexity and diversity of the related regulations, legitimacy concerns, and health and environmental risks, are among the most important challenges that require a strong commitment at the national/international levels to reach a global consensus.
Fourth generation biofuel from genetically modified algal biomass for bioeconomic development

Shokravi H, Heidarrezaei M, Shokravi Z, Ong HC, Lau WJ, Din MFM, et al.

J Biotechnol, 2022 Dec 10;360:23-36.
PMID: 36272575 DOI: 10.1016/j.jbiotec.2022.10.010

Biofuels from microalgae have promising potential for a sustainable bioeconomy. Algal strains' oil content and biomass yield are the most influential cost drivers in the fourth generation biofuel (FGB) production. Genetic modification is the key to improving oil accumulation and biomass yield, consequently developing the bioeconomy. This paper discusses current practices, new insights, and emerging trends in genetic modification and their bioeconomic impact on FGB production. It was demonstrated that enhancing the oil and biomass yield could significantly improve the probability of economic success and the net present value of the FGB production process. The techno-economic and socioeconomic burden of using genetically modified (GM) strains and the preventive control strategies on the bioeconomy of FGB production is reviewed. It is shown that the fully lined open raceway pond could cost up to 25% more than unlined ponds. The cost of a plastic hoop air-supported greenhouse covering cultivation ponds is estimated to be US 60,000$ /ha. The competitiveness and profitability of large-scale cultivation of GM biomass are significantly locked to techno-economic and socioeconomic drivers. Nonetheless, it necessitates further research and careful long-term follow-up studies to understand the mechanism that affects these parameters the most.
Analysis of the performance, emission and combustion characteristics of a turbocharged diesel engine fuelled with Jatropha curcas biodiesel-diesel blends using kernel-based extreme learning machine

Silitonga AS, Hassan MH, Ong HC, Kusumo F

Environ Sci Pollut Res Int, 2017 Nov;24(32):25383-25405.
PMID: 28932948 DOI: 10.1007/s11356-017-0141-9

The purpose of this study is to investigate the performance, emission and combustion characteristics of a four-cylinder common-rail turbocharged diesel engine fuelled with Jatropha curcas biodiesel-diesel blends. A kernel-based extreme learning machine (KELM) model is developed in this study using MATLAB software in order to predict the performance, combustion and emission characteristics of the engine. To acquire the data for training and testing the KELM model, the engine speed was selected as the input parameter, whereas the performance, exhaust emissions and combustion characteristics were chosen as the output parameters of the KELM model. The performance, emissions and combustion characteristics predicted by the KELM model were validated by comparing the predicted data with the experimental data. The results show that the coefficient of determination of the parameters is within a range of 0.9805-0.9991 for both the KELM model and the experimental data. The mean absolute percentage error is within a range of 0.1259-2.3838. This study shows that KELM modelling is a useful technique in biodiesel production since it facilitates scientists and researchers to predict the performance, exhaust emissions and combustion characteristics of internal combustion engines with high accuracy.
In vitro antidermatophytic activity and cytotoxicity of extracts derived from medicinal plants and marine algae

Sit NW, Chan YS, Lai SC, Lim LN, Looi GT, Tay PL, et al.

J Mycol Med, 2018 Sep;28(3):561-567.
PMID: 30060991 DOI: 10.1016/j.mycmed.2018.07.001

OBJECTIVES: This study was conducted to evaluate the antidermatophytic activity of 48 extracts obtained from medicinal plants (Cibotium barometz, Melastoma malabathricum, Meuhlenbeckia platyclada, Rhapis excelsa, Syzygium myrtifolium, Vernonia amygdalina) and marine algae (Caulerpa sertularioides, Kappaphycus alvarezii) against Trichophyton rubrum and Trichophyton interdigitale (ATCC reference strains), and the cytotoxicity using African monkey kidney epithelial (Vero) cells. Active plant extracts were screened for the presence of phytochemicals and tested against clinical isolates of Trichophyton tonsurans.
METHODS: Six different extracts (hexane, chloroform, ethyl acetate, ethanol, methanol and water) were obtained from each plant or algae sample using sequential solvent extraction. The antidermatophytic activity for the extracts was assessed using a colourimetric broth microdilution method. The viability of Vero cells was measured by Neutral Red uptake assay.
RESULTS: All the extracts (except the water extracts of V. amygdalina, C. sertularioides and K. alvarezii) showed antidermatophytic activity against Trichophyton spp. The minimum fungicidal concentration (MFC) ranges for the plant extracts against T. rubrum and T. interdigitale are 0.0025-2.50 and 0.005-2.50mg/mL, respectively. The algae extracts exhibited lower potency against both species, showing MFC ranges of 0.08-2.50 and 0.31-2.50mg/mL, respectively. The ethanol and methanol extracts from the leaves of R. excelsa, and the methanol and water extracts from the leaves of S. myrtifolium were highly active (MFC<0.1mg/mL) and with high selectivity indices (SI>2.8) against reference strains of T. rubrum and T. interdigitale, and most of the clinical isolates of T. tonsurans. Phytochemical analysis indicates the presence of alkaloids, anthraquinones, flavonoids, saponins, tannins, phenolics and triterpenoids in the extracts.
CONCLUSIONS: The medicinal plant extracts exhibited stronger antidermatophytic activity compared to the algae extracts. The leaves of R. excelsa and S. myrtifolium are potential sources of new antidermatophytic agents against Trichophyton spp.
Perspectives on cultivation and harvesting technologies of microalgae, towards environmental sustainability and life cycle analysis

Soudagar MEM, Kiong TS, Jathar L, Nik Ghazali NN, Ramesh S, Awasarmol U, et al.

Chemosphere, 2024 Apr;353:141540.
PMID: 38423144 DOI: 10.1016/j.chemosphere.2024.141540

The development of algae is seen as a potential and ecologically sound approach to address the increasing demands in multiple sectors. However, successful implementation of processes is highly dependent on effective growing and harvesting methods. The present study provides a complete examination of contemporary techniques employed in the production and harvesting of algae, with a particular emphasis on their sustainability. The review begins by examining several culture strategies, encompassing open ponds, closed photobioreactors, and raceway ponds. The analysis of each method is conducted in a systematic manner, with a particular focus on highlighting their advantages, limitations, and potential for expansion. This approach ensures that the conversation is in line with the objectives of sustainability. Moreover, this study explores essential elements of algae harvesting, including the processes of cell separation, dewatering, and biomass extraction. Traditional methods such as centrifugation, filtration, and sedimentation are examined in conjunction with novel, environmentally concerned strategies including flocculation, electro-coagulation, and membrane filtration. It evaluates the impacts on the environment that are caused by the cultivation process, including the usage of water and land, the use of energy, the production of carbon dioxide, and the runoff of nutrients. Furthermore, this study presents a thorough examination of the current body of research pertaining to Life Cycle Analysis (LCA) studies, presenting a perspective that emphasizes sustainability in the context of algae harvesting systems. In conclusion, the analysis ends up with an examination ahead at potential areas for future study in the cultivation and harvesting of algae. This review is an essential guide for scientists, policymakers, and industry experts associated with the advancement and implementation of algae-based technologies.

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