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  1. Tan AE, Norizah WM, Rahman HA, Aziz BA, Cheah FC
    J Obstet Gynaecol Res, 2005 Aug;31(4):296-301.
    PMID: 16018775 DOI: 10.1111/j.1447-0756.2005.00291.x
    Aim: To determine the incidence of an abnormal umbilical artery resistance index (UARI) in diabetic pregnancies and the relation to fetal outcome and the development of neonatal septal hypertrophic cardiomyopathy.

    Methods: A case-control study with subjects comprising 50 randomly selected diabetic mothers and a matched control group of 50 non-diabetic pregnancies. Doppler studies of the UARI were carried out at least once per week, beginning from 36 weeks' gestation for both groups. Within 48 h post delivery, echocardiograms were carried out on the newborn infants to identify those with hypertrophic cardiomyopathy, particularly asymmetrical septal hypertrophy.

    Results: The numbers of patients with abnormal UARI were similar in both the diabetic and control groups. A higher proportion of operative deliveries for intrapartum fetal distress was seen in patients with an abnormal UARI in the diabetic group. However, the groups did not differ in the numbers of infants who were small for gestational age, who had low Apgar scores or umbilical artery acidosis, and who required admission to the special care nursery. Six infants of diabetic mothers (12%) had septal hypertrophy, but none of these were associated with abnormal antenatal UARI.

    Conclusion: Diabetic pregnancy is not associated with a significantly higher incidence of abnormal UARI on Doppler study than non-diabetic pregnancy. UARI is not a useful single indicator by which to predict subsequent fetal outcome or the development of neonatal septal hypertrophic cardiomyopathy in diabetic pregnancies.
  2. Ang LW, Ma S, Cutter J, Chew SK, Tan CE, Tai ES
    Diabetes Res Clin Pract, 2005 Jan;67(1):53-62.
    PMID: 15620434 DOI: 10.1016/j.diabres.2004.05.003
    We used factor analysis to define and compare the manner in which the various features of the metabolic syndrome are linked or clustered in Chinese, Malays and Asian Indians. One thousand nine hundred and fifty seven men (1324 Chinese, 391 Malays and 261 Asian Indians) and 2308 women (1622 Chinese, 391 Malays and 296 Asian Indians) were examined. Anthropometry, blood pressure, serum glucose, lipid concentrations, and serum insulin were measured for all subjects. These data were then subjected to factor analysis which reduced the variables examined to three factors in all ethnic groups and both genders. The first (dyslipidemia) factor was positively loaded for obesity, insulin resistance (IR), fasting triglyceride and negatively loaded for HDL-cholesterol. The second (hyperglycemia) factor was positively loaded for IR and blood glucose. The third (hypertension) factor was positively loaded for obesity and blood pressure. IR was positively loaded in the hypertension factor in Malay women but not in others. Rather than a single entity causally associated with insulin resistance (IR), our findings support a concept in which the metabolic syndrome represents several distinct entities (dyslipidemia, hypertension and hyperglycemia). It appears that Malay females may be more prone to develop hypertension in association with IR.
  3. Tan SM, Shafiee Z, Wu LL, Rizal AM, Rey JM
    Int J Psychiatry Med, 2005;35(2):123-36.
    PMID: 16240970 DOI: 10.2190/EQ71-RMWV-6CEJ-1DGM
    Objectives: To examine the association between ethnicity, depression, quality of life, and diabetic control in Malaysian adolescents and young adults with type I diabetes mellitus.

    Methods: Fifty-two outpatients with type I diabetes (mean age 15.5 years) who attended a Diabetes Clinic were included. The level of HbA1c was the measure of diabetes control used (better control defined as HbA1c < 10%). Other variables were measured through questionnaires (e.g., depressive symptoms, quality of life), computerized diagnostic interviews (major depression), and medical records (e.g., demographic, family circumstances, compliance with treatment).

    Results: Ethnic Chinese youth showed better diabetic control than Malays and Indians (mean HbA1c 9.1%, 10.3%, and 11.0% respectively). Young people with better diabetic control (HbA1c < 10%) were more likely to have better quality of life and less likely to live in problematic families. When the cut-off for diabetic control was stricter (HbA1c < or = 8%), the young person's compliance was the main predictor of poor control. Family problems were also associated with poor control but to a lesser extent. The initial association between poorer diabetes control and depression became non-significant when quality of life was taken into account.

    Conclusions: There are ethnic differences in juvenile diabetic control in this Malaysian sample which need to be understood further. Previous findings of an association between quality of life and glycemic control were verified but different definitions of good control showed different associations with individual and environmental variables. Clinicians' awareness and early intervention for psychosocial problems (for example, inadequate family support) could improve diabetes control.
  4. Deurenberg-Yap M, Li T, Tan WL, van Staveren WA, Chew SK, Deurenberg P
    Asia Pac J Clin Nutr, 2001;10(1):39-45.
    PMID: 11708607
    In Singapore. there exists differences in risk factors for coronary heart disease among the three main ethnic groups: Chinese, Malays and Indians. This study aimed to investigate if differences in dietary intakes of fat, types of fat, cholesterol, fruits, vegetables and grain foods could explain the differences in serum cholesterol levels between the ethnic groups. A total of 2408 adult subjects (61.0% Chinese, 21.4% Malays and 17.6% Indians) were selected systematically from the subjects who took part in the National Health Survey in 1998. The design of the study was based on a cross-sectional study. A food frequency questionnaire was used to assess intakes of energy, total fat, saturated fat, polyunsaturated fat, monounsaturated fat, cholesterol, fruits, vegetables and cereal-based foods. The Hegsted score was calculated. Serum total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol were analysed and the ratio of total cholesterol to high density lipoprotein cholesterol was computed. The results showed that on a group level (six sex-ethnic groups), Hegsted score, dietary intakes of fat, satutrated fat, cholesterol, vegetables and grain foods were found to be correlated to serum cholesterol levels. However, selected dietary factors did not explain the differences in serum cholesterol levels between ethnic groups when multivariate regression analysis was performed, with adjustment for age, body mass index, waist-hip ratio, cigarette smoking, occupation, education level and physical activity level. This cross-sectional study shows that while selected dietary factors are correlated to serum cholesterol at a group level, they do not explain the differences in serum cholesterol levels between ethnic groups independently of age, obesity, occupation, educational level and other lifestyle risk factors.
  5. Tee ES, Tamin S, Ilyas R, Ramos A, Tan WL, Lai DK, et al.
    Asia Pac J Clin Nutr, 2002;11(2):S80-6.
    PMID: 12074192
    This review includes the situation of nutrition labelling and claims in six countries in South-East Asia: Brunei, Indonesia, Malaysia, Philippines, Singapore and Thailand. With the exception of Malaysia, there is no mandatory nutrition labelling requirements for foods in these countries except for special categories of foods and when nutritional claims are made for fortified or enriched foods. Nevertheless, several food manufacturers, especially multinationals, do voluntarily label the nutritional content of a number of food products. There is, therefore, increasing interest among authorities in countries in the region to start formulating regulations for nutrition labelling for a wider variety of foods. Malaysia has proposed new regulations to make it mandatory to label a number of foodstuffs with the four core nutrients, protein, carbohydrate, fat and energy. Other countries have preferred to start with voluntary labelling by the manufacturers, but have spelt out the requirements for this voluntary labelling. The format and requirements for nutrition labelling differ widely for countries in the region. Some countries, such as Malaysia, closely follow the Codex guidelines on nutrition labelling in terms of format, components to be included and mode of expression. Other countries, such as the Philippines and Thailand, have drafted nutrition labelling regulations very similar to those of the Nutrition Labeling and Education Act (NLEA) of the United States. Nutrition and health claims are also not specifically permitted under food regulations that were enacted before 1998. However, various food products on the market have been carrying a variety of nutrition and health claims. There is concern that without proper regulations, the food industry may not be certain as to what claims can be made. Excessive and misleading claims made by irresponsible manufacturers would only serve to confuse and mislead the consumer. In recent years, there has been efforts in countries in the region to enact regulations on nutrition claims. Recently enacted regulations or amendments to existing regulations of almost all the countries reviewed have included provisions for nutrition claims. Malaysia is in the process of gazetting regulations to clearly stipulate the permitted nutrition claims and the conditions required to make these claims along the guidelines of Codex Alimentarius Commission. Only two countries in the region permit health claims to be made - Indonesia and Philippines. Other countries in the region are following developments in Codex and examining the need for allowing these claims. There are more differences than similarities in the regulations on nutrition labelling and claims among countries in the South-East Asian region as no previous efforts have been made to address these. Hopefully, through this first regional meeting, countries can initiate closer interaction, with a view to working towards greater harmonization of nutrition labelling and health claims in the region.
  6. Osman A, Khalida M, Azman AB, Jamil R, Tan TT, Wu LL, et al.
    Asia Pac J Clin Nutr, 1993 Sep;2(3):115-8.
    PMID: 24352141
    The prevalence of goitre was determined in several communities in rural parts of Pahang. Urine specimens were collected randomly among the participants. Drinking water from various sources such as river and spring, and water from gravity feed systems was also collected to determine the iodine content by using the ashing method. The results were compared to that of Kuala Lumpur City. lt was found that the prevalence of goitre in rural areas was between 20 and 70% depending on village, ethnic group, age and gender. The interior parts of the jungle where Aborigines lived was moderately endemic with goitre prevalence of goitre more than 20% and urinary iodine content 2.0-5.0 μg I/dl). A nearby Malay traditional village which was studied had mild endemia (prevalence 10-30% and urinary iodine content 5.0-10.0 μg I/dl) while a Felda Malay resettlement scheme and Kuala Lumpur City did not have endemic goitre. Endemic goitre in rural areas was associated with low iodine content in drinking water. Even though Kuala Lumpur had low iodine content in its drinking water there was no endemic goitre, indicating that other factors were more important.
  7. Wan Nazaimoona WM, Osman A, Ng ML, Tan TT, Wu LL, Sakinah O, et al.
    Asia Pac J Clin Nutr, 1992 Dec;1(4):207-10.
    PMID: 24323236
    Insulin-like growth factor-I (IGF-I)and fasting growth hormone levels were measured in a group of 255 children (163 males and 92 females. age ranged 6-17 years) of varying pubertal development and body mass index (BMI); well-nourished (BMI> 18). mildly-malnourished (BMI = 15-18) and moderately-malnourished (BMI<15). In well-nourished children IGF-I levels increased significantly (P = 0.02) with pubertal development. where girls at Tanner 5 had significantly higher (p = 0.03) IGF-I levels than the boys. Whilst there was no change in fasting GH levels with nutritional status, IGF-I levels of prepubertal boys and girls decreased significantly with BMI (P<0.001 and P = 0.01 respectively). Hence. measurement of IGF-I levels is a sensitive biochemical index in the assessment of mild and moderate form of malnutrition in prepubertal children.
  8. Wee AS, Lim CK, Tan SL, Ahmad TS, Kamarul T
    Tissue Eng Part C Methods, 2022 10;28(10):501-510.
    PMID: 36082992 DOI: 10.1089/ten.TEC.2022.0112
    Transforming growth factor-beta 1 (TGF-β1) has been reported to promote chondrogenic differentiation and proliferation in the multipotent stromal cell (MSCs), and the transforming growth factor-beta 3 (TGF-β3) tends to be exclusively in promoting cell differentiation alone. The objective of this study was to determine the effect of TGF-β1 and -β3 on the MSCs chondrogenic differentiation on the poly (vinyl alcohol)-chitosan-poly (ethylene glycol) (PVA-NOCC-PEG) scaffold, compared with that of monolayer and pellet cultures. In this study, P2 rabbit bone marrow-derived MSCs were seeded either on the untreated six-well plate (for monolayer culture) or onto the PVA-NOCC-PEG scaffold or cultured as a pellet culture. The cultures were maintained in a chemically defined serum-free medium supplemented with 10 ng/mL of either TGF-β1 or TGF-β3. Cell viability assay, biochemical assay, and real-time polymerase chain reaction were performed to determine the net effect of cell proliferation and chondrogenic differentiation of each of the growth factors. The results showed that the PVA-NOCC-PEG scaffold enhanced MSCs cell proliferation from day 12 to 30 (p  0.05). In terms of chondrogenic differentiation, the PVA-NOCC-PEG scaffold augmented the GAGs secretion in MSCs and the mRNA expression levels of Sox9, Col2a1, Acan, and Comp were elevated (p  0.05). In conclusion, TGF-β1 and TGF-β3 enhanced the chondrogenic differentiation of MSCs seeded on the PVA-NOCC-PEG scaffold; however, there was no significant difference between the effect of TGF-β1 and TGF-β3. Impact statement Transforming growth factor-beta (TGF-β) superfamily members is a key requirement for the in vitro chondrogenic differentiation of mesenchymal stem cells (MSCs). In this study, the effects of TGF-β1 and -β3 on MSC chondrogenic differentiation and proliferation on a novel three-dimensional scaffold, the poly(vinyl alcohol)-chitosan-poly(ethylene glycol) (PVA-NOCC-PEG) scaffold, was evaluated. In this study, the results showed both TGF-β1 and TGF-β3 can enhance the chondrogenic differentiation of MSCs seeded on the PVA-NOCC-PEG scaffold.
  9. Goh TX, Tan SL, Roebuck MM, Teo SH, Kamarul T
    Tissue Eng Part C Methods, 2022 10;28(10):511-528.
    PMID: 35959742 DOI: 10.1089/ten.TEC.2022.0092
    The state of host cells is reflected in the cargo carried by their extracellular vesicles (EVs). This makes EV a potential source of biomarkers for human diseases. Piwi-interacting RNA (piRNA) regulates gene expression through epigenetic regulation and post-transcriptional gene silencing. Thus, piRNA profiling in EVs derived from human clinical samples could identify markers that characterize disease stages and unveil their roles in disease pathology. This review aimed to report the expression profiles of EV-derived piRNA (EV-piRNA) in various human samples, as well as their role in each pathology. A systematic review was conducted to collate the findings of human EV-piRNA from original research articles published in indexed scientific journals up to February 16, 2022. Article searches were performed in PubMed, Web of Science, and Scopus databases, using a combination of keywords, including "EV" and "piRNA." A total of 775 nonredundant original articles were identified. After subjecting articles to inclusion and exclusion criteria, 34 articles were accepted for this review. The piRNA expression levels among the small RNA profiles of human-derived EVs range from 0.09% to 43.84%, with the lowest expression level reported in urine-derived EVs and the highest percentage in plasma-derived EVs. Differentially expressed EV-piRNAs have been identified in patients with specific disease conditions compared to their counterparts (healthy control), suggesting an association between piRNA and progression in various diseases. Seven articles identified piRNA putative target genes and/or the pathway enrichment of piRNA target genes, and one study demonstrated a direct role of piRNA candidates in disease pathology. In conclusion, EV-piRNA has been isolated successfully from various human body fluids. EV-piRNA is a new research niche in human disease pathology. The expression profiles of EV-piRNA in various tissue types and disease conditions remain largely unexplored. Furthermore, there is currently a lack of guidelines on piRNA bioinformatics analysis, which could lead to inconsistent results and thus hinder the progression of piRNA discoveries. Finally, the lack of published scientific evidence on the role of EV-piRNA supports the need for future research to focus on the functional analysis of EV-piRNA as part of the route in piRNA discoveries.
  10. Kamarudin M, Chong WK, Hamdan M, Adlan AS, Saaid R, Tan PC
    BMC Pregnancy Childbirth, 2022 Nov 04;22(1):812.
    PMID: 36333791 DOI: 10.1186/s12884-022-05162-4
    BACKGROUND: Bladder overdistension in labor may lead to prolonged postpartum urinary retention. We hypothesized that nulliparas mobilizing to toilet is more likely to achieve satisfactory micturition.

    METHODS: One hundred sixteen (58 in each arm) term nulliparas in labor with filled bladders were randomized to mobilizing to the toilet or using bedpan to micturate. Primary outcome was satisfactory micturition defined as ultrasound derived post-void bladder volume 

  11. Chua KH, Puah SM, Chew CH, Tan SY, Lian LH
    Ann Hum Biol, 2010 Apr;37(2):274-80.
    PMID: 19951233 DOI: 10.3109/03014460903325185
    In this study, we investigated the polymorphisms of the exon 1 (+49A/G), promoter sites (-1722T/C, -1661A/G, -318C/T), and 3'-untranslated region (3'-UTR) (+6230 A/G) of the CTLA-4 gene in systemic lupus erythematosus (SLE) affected patients. Polymerase chain reaction-restriction fragment length polymorphism was used to determine genotypes of these five markers in 130 SLE patients and 130 healthy controls. Of the five tested polymorphisms, there was no statistical significant difference between the genotypic and allelic frequencies of patients with SLE and controls. Hence, we propose that the CTLA-4 gene does not play a major role in the genetic susceptibility to the development of SLE in the Malaysian population.
  12. Tan JW, Tham CL, Israf DA, Lee SH, Kim MK
    Neurochem Res, 2013 Mar;38(3):512-8.
    PMID: 23224778 DOI: 10.1007/s11064-012-0943-6
    L-Glutamate plays a crucial role in neuronal cell death, which is known to be associated with various neurodegenerative diseases, such as Alzheimer's, Parkinson's, and Huntington's diseases. In this study, we investigated the protective effects of biochanin A, a phytoestrogen compound found mainly in Trifolium pratense, against L-glutamate-induced cytotoxicity in a PC12 cell line. Exposure of the cells to 10 mM L-glutamate was found to significantly increase cell viability loss and apoptosis, whereas pretreatment with various concentrations of biochanin A attenuated the cytotoxic effects of L-glutamate. Specifically, the pretreatment led to not only decreases in the release of lactate dehydrogenase, the number of apoptotic cells, and the activity of caspase-3 but also an increase in the total glutathione level in the L-glutamate-treated PC12 cells. These results indicate that biochanin A may be able to exert neuroprotective effects against L-glutamate-induced cytotoxicity. Furthermore, our findings also imply that biochanin A may act as an antiapoptotic agent in order to perform its protective function.
  13. Zhou F, Lin S, Zhang J, Kong Z, Tan BK, Hamzah SS, et al.
    Photodiagnosis Photodyn Ther, 2021 Dec 08;37:102677.
    PMID: 34890782 DOI: 10.1016/j.pdpdt.2021.102677
    BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa) is an emerging opportunistic pathogen, which can cause bacterial skin diseases such as green nail syndrome, interdigital infections and folliculitis. Curcumin-mediated antimicrobial photodynamic therapy (aPDT) has been demonstrated as a promising therapeutic option for the treatment of skin infection though its inactivation of gram-negative bacteria such as P. aeruginosa.

    MATERIALS AND METHODS: In the present study, we examined the adjuvant effect of polymyxin B on the antibacterial activity of curcumin-mediated aPDT against P. aeruginosa. P. aeruginosa was treated with curcumin in the presence of 0.1-0.5 mg/L polymyxin B and irradiated by blue LED light (10 J/cm2). Bacterial cultures treated with curcumin alone served as controls. Colony forming units (CFU) were counted and the viability of P. aeruginosa was calculated after aPDT treatment. The possible underlying mechanisms for the enhanced killing effects were also explored.

    RESULTS: The killing effects of curcumin-mediated aPDT against P. aeruginosa was significantly enhanced by polymyxin B (over 2-log reductions). Moreover, it was also observed that addition of polymyxin B in the curcumin-mediated aPDT led to the apparent bacterial membrane damage with increased leakage of cytoplasmic contents and extensive DNA and protein degradation.

    DISCUSSION: The photodynamic action of curcumin against P. aeruginosa could be significantly enhanced by the FDA-approved drug polymyxin B. Our results highlight the potential of introducing polymyxin B to enhance the effects of aPDT treatment against gram-negative skin infections, in particular, P. aeruginosa.

  14. Jamaluddin ND, Mazlan NF, Tan LL, Yusof NYM, Khalid B
    Int J Biol Macromol, 2022 Feb 28;199:1-9.
    PMID: 34922999 DOI: 10.1016/j.ijbiomac.2021.12.047
    Dengue virus (DENV) is a positive-sense single-stranded RNA virus and that the detection of viral RNA itself is highly desirable, which can be achieved by using RNA biosensor diagnostic method. Herein, acrylic micropolymer-based optical RNA biosensor was developed by binding anionic copper(II) phthalocyanine (CPC) planar aromatic ligand to the G-quadruplex DNA probe via end-stacking with π-system of the guanine (G) quartet, and a blue coloration was developed on the G-quadruplex microspheres. Hybridization of G-quadruplex DNA probe with target DENV serotype 2 (DENV2) RNA unfolded the G-quadruplex, and rendering release of the CPC planar optical label, causing discoloration of the G-quadruplex microbiosensor. Optical characterization of the RNA biosensor was performed by means of fiber optic reflectance spectrophotometer at maximum reflectance wavelength of 774 nm. The reflectance response enhancement of the RNA-responsive G-quadruplex-based reflectometric biosensor was linearly proportional to the target oligo DENV2 RNA concentration in the range of 2 zM-2 μM, with a 0.447 zM limit of detection and a rapid response time of 30 min. Heightening in the reflectance signal based on structural transition of G-quadruplex in response to target RNA was successfully implemented in real-time DENV2 detection in non-invasive human fluid samples (i.e. saliva and urine) under informed consent.
  15. Tong KL, Tan KE, Lim YY, Tien XY, Wong PF
    Mol Cell Biochem, 2022 Dec;477(12):2703-2733.
    PMID: 35604519 DOI: 10.1007/s11010-022-04455-8
    Atherosclerosis is the major cause of coronary artery disease (CAD) which includes unstable angina, myocardial infarction, and heart failure. The onset of atherogenesis, a process of atherosclerotic lesion formation in the intima of arteries, is driven by lipid accumulation, a vicious cycle of reactive oxygen species (ROS)-induced oxidative stress and inflammatory reactions leading to endothelial cell (EC) dysfunction, vascular smooth muscle cell (VSMC) activation, and foam cell formation which further fuel plaque formation and destabilization. In recent years, there is a surge in the number of publications reporting the involvement of circular RNAs (circRNAs) in the pathogenesis of cardiovascular diseases, cancers, and metabolic syndromes. These studies have advanced our understanding on the biological functions of circRNAs. One of the most common mechanism of action of circRNAs reported is the sponging of microRNAs (miRNAs) by binding to the miRNAs response element (MRE), thereby indirectly increases the transcription of their target messenger RNAs (mRNAs). Individual networks of circRNA-miRNA-mRNA associated with atherogenesis have been extensively reported, however, there is a need to connect these findings for a complete overview. This review aims to provide an update on atherogenesis-related circRNAs and analyze the circRNA-miRNA-mRNA interactions in atherogenesis. The atherogenic mechanisms and clinical relevance of each atherogenesis-related circRNA were systematically discussed for better understanding of the knowledge gap in this area.
  16. Ang CW, Tan MM, Bärnighausen T, Reininghaus U, Reidpath D, Su TT
    Sci Rep, 2022 Sep 23;12(1):15910.
    PMID: 36151113 DOI: 10.1038/s41598-022-20020-1
    Hypertension might be a contributing factor of mental illness. The aim of this study was to investigate the association between different levels of hypertension care and mental distress among hypertensive individuals in Malaysia. We constructed a hypertension care cascade using data of 6531 hypertensive individuals aged ≥ 35 years that were collected as part of the community health survey conducted in 2013 in the South East Asia Community Observatory. We examined the association between the status of hypertension care and mental distress using multiple logistic regressions. Respondents who had not been screened for hypertension and those who had uncontrolled blood pressure (BP) had higher odds of depression, anxiety and, stress compared to those who had been screened and those who had controlled BP, respectively. Respondents who were not taking antihypertensive medication had lower odds of depression and anxiety compared to those who were on medication. There was an association between different levels of hypertension care and mental distress. The application of a hypertension care cascade may help improve the provision of mental health support in primary care clinics. Specific mental health interventions could be provided for patients with particular needs along the cascade.
  17. Chew ZL, Tan EH, Palaniandy SA, Woon KS, Phuang ZX
    Sci Total Environ, 2023 Jan 15;856(Pt 1):159007.
    PMID: 36167122 DOI: 10.1016/j.scitotenv.2022.159007
    Improper discard of oil palm trunk and empty fruit bunch renders massive greenhouse gases. Turning these palm wastes into solid biofuels could aid in carbon reduction. The embodied environmental impacts of the solid biofuel densification process are neglected in carbon emission quantification studies applying Greenhouse Gas Protocol while the significance of classifying the system's direct and indirect carbon emissions were overlooked in those utilising life cycle assessment. Despite the prospect of both methodologies to complement their limitations for carbon emissions quantification, no study integrates both methodologies to investigate direct and indirect emissions systematically from a life cycle perspective. An integrated framework of life cycle assessment and Greenhouse Gas Protocol is developed to quantify the direct and indirect carbon emissions of oil palm trunk and empty fruit bunch densification from cradle-to-gate for three pellet plants in Indonesia and Malaysia. The emissions are categorised into three emission scopes: Scope 1, Scope 2, and Scope 3 according to the Greenhouse Gas Protocol, integrated with avoided emissions which are quantified via life cycle assessment. The pellet plants generate 534.7-732.3 kg CO2-eq/tonnepellet per hour, in which Scope 1 (i.e., direct emissions) is the major emission scope due to high emissions from wastewater production and drying fuel combustion. Washing equipment (169.2-439.0 kg CO2-eq/tonnepellet per hour) and burners (87.1-214.5 kg CO2-eq/tonnepellet per hour) are the hotspots found in the pellet plants. Producing empty fruit bunch pellets could reduce 62.0-74.1 % of emissions than landfilling the empty fruit bunch. Empty fruit bunch pellet and oil palm trunk pellet are recommended to co-fire with coal to phase down coal usage in achieving COP26 pledge. This study provides data-driven insights for quantifying carbon emissions through the integrated framework and could be a reference in future life cycle carbon footprint studies of the biomass densification process.
  18. Mustafa S, Hassan NB, Tan SC, Ab Rahman AK, Low LL, Wan Yusuf WN
    Turk J Med Sci, 2016 Dec 20;46(6):1875-1881.
    PMID: 28081342 DOI: 10.3906/sag-1503-116
    BACKGROUND/AIM: Nevirapine is a reverse-transcriptase inhibitor widely used in combination therapy to treat HIV infection. Nevirapine is extensively metabolized in the liver and CYP2B6 is mainly responsible for oxidation of 3-hydroxynevirapine (3-OH NVP). This study aims to explore CYP2B6 activity by measuring 2-hydroxynevirapine (2-OH NVP) and 3-OH NVP in plasma and to identify factors associated with nevirapine pharmacokinetic parameters.

    MATERIALS AND METHODS: A total of 112 patients were recruited and treated with nevirapine-based antiretroviral therapy. Plasma nevirapine and metabolite concentrations were assayed using high-performance liquid chromatography via liquid-liquid extraction.

    RESULTS: Thirty-nine (34.8%) of the patients had no 3-OH NVP detected in their plasma while 2-OH NVP was detected in all patients. Metabolite concentrations were low compared to nevirapine. Positive correlations were observed between nevirapine and its metabolites, 2-OH NVP (P < 0.01) and 3-OH NVP (P = 0.012). Nevirapine concentration was decreased when concomitantly administered with methadone. Univariate analysis showed that ALT level, AST level, and detection of 3-OH NVP were associated with nevirapine pharmacokinetic parameters.

    CONCLUSION: The variability of nevirapine pharmacokinetic parameters was caused by liver enzymes and the presence of 3-OH NVP metabolites. The presence of 3-OH NVP can probably be used to distinguished CYP2B6 activity and efficacy of nevirapine in patients with HIV infection.

  19. Lim SM, Pang ZW, Tan HY, Shaikh M, Adinarayana G, Garg S
    Drug Dev Ind Pharm, 2015;41(11):1847-55.
    PMID: 25721984 DOI: 10.3109/03639045.2015.1014818
    Poor biopharmaceutical properties and toxicities associated with the intravenous formulation of docetaxel (DTX) necessitate the exploration of an alternate oral route of delivery.
  20. Wong EYL, Loh GOK, Tan YTF, Peh KK
    Drug Dev Ind Pharm, 2021 Feb;47(2):197-206.
    PMID: 33300818 DOI: 10.1080/03639045.2020.1862177
    OBJECTIVE: The aim of the study was to develop a simple, highthroughput and sensitive LC-MS/MS method and apply to a bioequivalence study of montelukast, a light sensitive drug.

    METHOD: The effects of organic modifiers in mobile phase, protein precipitation agent to plasma sample ratio, and light on montelukast stability in unprocessed and processed human plasma, were evaluated. Validation was conducted in accordance with European Medicines Agency Guideline on bioanalytical method validation.

    RESULTS: No interference peak was observed when acetonitrile was used as an organic modifier. Acetonitrile to plasma ratio of 4:1 produced clean plasma sample. Approximately 3 % of cis isomer was detected in unprocessed plasma samples while 21 % of cis isomer was detected in processed plasma samples after exposing to fluorescent light for 24h. The standard calibration curve was linear over 3.00-1200.00 ng/mL. All method validation parameters were within the acceptance criteria.

    CONCLUSION: The validated method was successfully applied to a bioequivalence study of two montelukast formulations involving 24 healthy Malaysian volunteers. The light stability of a light sensitive drug in unprocessed and processed human plasma samples should be studied prior to pharmacokinetic/bioequivalence studies. Measures could then be taken to protect the analyte in human plasma from light degradation.

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