Kah Hay Yuen

• B Pharm(hons), M.Sc, PhD
• Professor at School of Pharmaceutical Sciences, University of Science Malaysia, Glugor, Penang

Piroxicam, a nonsteroidal anti-inflammatory drug, has been shown with low oral bioavailability and delayed onset of its therapeutic effects. In this work, a promising nano/liposomal drug delivery system was exploited to improve the in vivo therapeutic efficacies of piroxicam. The current liposome-encapsulated piroxicam formulation effectively boost...

The issue of vaginal dryness in genitourinary syndrome of menopause (GSM) and its pervasive impact on women's quality of life is often overlooked. Extensive surveys conducted worldwide reveal limited understanding of vaginal dryness among public and health-care providers. Physician knowledge on menopause medicine varies globally, highlighting the n...

Aim nlmixr offers first‐order conditional estimation (FOCE), FOCE with interaction (FOCEi) and stochastic approximation estimation‐maximisation (SAEM) to fit nonlinear mixed‐effect models (NLMEM). We modelled metformin's pharmacokinetic data using nlmixr and investigated SAEM and FOCEi's performance with respect to bias and precision of parameter e...

Self-emulsifying drug delivery systems (SEDDS) have been shown to enhance the water-solubility and oral bioavailability of poorly water-soluble compound. Solid SEDDS (s-SEDDS) address the stability and compatibility issues associated with conventional liquid SEDDS, but have limitations including the use high amounts of surfactants and complex proce...

White matter lesions (WML) underlie multiple brain disorders, and automatic WML segmentation is crucial to evaluate the natural disease course and effectiveness of clinical interventions, including drug discovery. Although recent research has achieved tremendous progress in WML segmentation, accurate detection of subtle WML present early in the dis...

Aim: nlmixr offers first-order conditional estimation with or without interaction (FOCE or FOCEi) and stochastic approximation estimation-maximisation (SAEM) to fit nonlinear mixed-effect models (NLMEM). We modelled metformin’s population pharmacokinetics with flip-flop characteristics within nlmixr framework and investigated SAEM and FOCEi’s perfo...

Self-emulsifying drug delivery systems (SEDDS) can improve the oral bioavailability of poorly water-soluble drugs. Solid self-emulsifying drug delivery systems (s-SEDDS) offer several advantages including improved drug stability, ease of administration, and production. Most compounds employed in developing s-SEDDS are solid in nature, with a high a...

A female patient in her 40’s of mixed Chinese-Indian ancestry was referred to our neurology clinic for frequent migraine with aura and CADASIL. She had been treated for acute encephalopathy in 2014. The incident led to her CADASIL diagnosis and later retinitis pigmentosa, both rare conditions. Initial clinical assessment showed moderate severity of...

Introduction: Stroke is a major health problem and the second leading cause of death worldwide. In Malaysia, it is the third largest cause of morbidity and mortality. To date, there is no clinically proven neuroprotective agent that can be used prophylactically to minimize the brain cells damage during a stroke nor is there any agent that can ameli...

There are several previous studies on the association of vitamin E with prevention of stroke but the findings remain controversial. We have conducted a systematic review, meta-analysis together with trial sequential analysis of randomised controlled trials to evaluate the effect of vitamin E supplementation versus placebo/no vitamin E on the risk r...

2,4,6-trihydroxy-3-geranylacetophenone (tHGA) is a bioactive compound that shows excellent anti-inflammatory properties. However, its pharmacokinetics and metabolism have yet to be evaluated. In this study, a sensitive LC-HRMS method was developed and validated to quantify tHGA in rat plasma. The method showed good linearity (0.5–80 ng/mL). The acc...

Background: Paracetamol/Orphenadrine is a fixed dose combination containing 35 mg orphenadrine and 450 mg paracetamol. It has analgesic and muscle relaxant properties and is widely available as generics. This study is conducted to investigate the relative bioavailability and bioequivalence between one fixed dose paracetamol/orphenadrine combinatio...

Aim: This study is conducted to compare the pharmacokinetic profiles of two fixed dose combination of metformin/glibenclamide tablets (500mg/5 mg per tablet). Materials and Methods: This is a single-center, single-dose, open-label, randomized, 2-treatment, 2-sequence and 2-period crossover study with a washout period of 7 days. All 28 adult male su...

Aim: This study is conducted to compare the pharmacokinetic profiles of two fixed dose combination of metformin/glibenclamide tablets (500mg/5 mg per tablet). Materials and methods: This is a single-center, single-dose, open-label, randomized, 2-treatment, 2-sequence and 2- period crossover study with a washout period of 7 days. All 28 adult mal...

Cerebral small vessel disease (CSVD) refers to a spectrum of clinical and neuroimaging findings resulting from pathological processes of various etiologies affecting cerebral arterioles, perforating arteries, capillaries, and venules. It is the commonest neurological problem that results in significant disability, but awareness of it remains poor....

Funding Acknowledgements This research was funded by Universiti Sains Malaysia Introduction Clopidogrel is a widely used P2Y12 antiplatelet drug. Patient"s compliance to clopidogrel is crucial to achieve therapeutic outcome and prevent thromboembolic events. While measuring serum level of clopidogrel and/or its active metabolite may indicate compl...

Nanocellulose, as a promising natural material, has recently received much attention because of its remarkable features including recyclability, biocompatibility, low risk of toxicity, tunable surface properties, etc. This review article first introduces three types of nanocellulose (NCC, NFC, and BNC) and evaluates their production processes. In a...

Objective: To estimate the minimum clinically important difference (MCID) of the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) and the International Consultation on Incontinence Questionnaire-Lower Urinary Tract Symptoms Quality of Life (ICIQ-LUTSqol) using both anchor-based and distribution-...

Background Coronary artery disease (CAD) claims lives yearly. Nuclear magnetic resonance (¹H NMR) metabolomics analysis is efficient in identifying metabolic biomarkers which lend credence to diagnosis. We aimed to identify CAD metabotypes and its implicated pathways using ¹H NMR analysis. Methods We analysed plasma and urine samples of 50 stable...

OBJECTIVES: This study aims to investigate the blood-brain barrier (BBB) permeability of curcumin analogues with shortened linkers and their ability to protect against amyloid-beta toxicity in a whole organism model. METHOD: Four curcumin analogues were synthesized. These analogues and curcumin were evaluated for their BBB permeability in the para...

Curcumin, the active ingredient of the rhizome curcuma longa has been extensively studied as an anticancer agent for various types of tumours. However, its efficacy as an anticancer agent is restricted due to poor absorption from the gastrointestinal tract, rapid metabolism and degradation in acidic medium. In the present study, we encapsulated cur...

A novel functional pumpkin-based beverage fermented by Lactobacillus mali K8 (FPJ) was produced. FPJ possessed higher ferric reducing antioxidant power (FRAP, 270.76 μM TE/100 ml) and radical scavenging activity (RSA‒IC50, 7.56 mg ml‒1) compared with non-inoculated control (PJ) (102.99 μM TE/100 ml and IC50 52.78 mg ml‒1). Up to an IC50 of 23.71 an...

Background: Atrial fibrillation (AF) is common after cardiac surgery and has been associated with poor outcome and increased resource utilization. The main objective of this study is to determine the incidence of POAF in Malaysia and identify the predictors of developing POAF. The secondary outcome of this study would be to investigate the differen...

Background: One of the most common complications following coronary artery bypass grafting (CABG) surgery is atrial fibrillation (AF), which contributes towards increasing morbidity and mortality, length of hospital stay (LoHS) and reduced quality of life (QoL) of patients. Objectives: To determine whether the intake of Tocotrienol, a Vitamin E iso...

Raw data for the study ‘A retrospective study on atrial fibrillation after coronary artery bypass grafting surgery at The National Heart Institute, Kuala Lumpur’ both in SAV and Excel formats

Abstract Background: One of the most common complications following coronary artery bypass grafting (CABG) surgery is atrial fibrillation (AF), which contributes towards increasing morbidity and mortality, length of hospital stay (LoHS) and reduced quality of life (QoL) of patients. Objectives: To determine whether the intake of Tocotrienol, a Vita...

Dual antiplatelet therapy (DAPT) of clopidogrel and aspirin is crucial for coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI). However, some patients may endure clopidogrel high on treatment platelets reactivity (HTPR) which may cause thromboembolic events. Clopidogrel HTPR is multifactorial with some genetic...

Background: One of the most common complications following coronary artery bypass grafting (CABG) surgery is atrial fibrillation (AF), which contributes towards increasing morbidity and mortality, length of hospital stay (LoHS) and reduced quality of life (QoL) of patients. Objectives: To determine whether the intake of Tocotrienol, a Vitamin E iso...

Background: Atrial fibrillation (AF) is common after cardiac surgery and has been associated with poor outcome and increased resource utilization. The main objective of this study is to determine the incidence of POAF in Malaysia and identify the predictors of developing POAF. The secondary outcome of this study would be to investigate the differen...

Importance Management of painful diabetic peripheral neuropathy remains challenging. Most therapies provide symptomatic relief with varying degrees of efficacy. Tocotrienols have modulatory effects on the neuropathy pathway and may reduce neuropathic symptoms with their antioxidative and anti-inflammatory activities. Objective To evaluate the effi...

Objective: In order for a measure to reliably evaluate treatment efficacy, it is important that the measure used has adequate responsiveness. However, the responsiveness of the Golombok Rust Inventory of Sexual Satisfaction (GRISS) questionnaire, a highly recommended questionnaire by the International Consultation of Incontinence to assess sexual...

Objective: To review measures used in recent randomized controlled trials evaluating stress urinary incontinence (SUI) treatments and to propose the most relevant outcome measure which should be included in future trials. Materials and methods: We identified randomized controlled trials for SUI interventions published between January 2015 and Ju...

In this study we used sparse data to predict optimum pH for cefotaxime sodium aqueous solutions stability using design of experiment (DoE) and artificial neural network (ANN). Cefotaxime aqueous solutions of pH 1, 4, 7 were prepared, separately in final drug concentration of 250 μg/mL and incubated at 37 °C under light protection. Samples of 1 mL w...

Objective: To evaluate the correlation between sexual function of couples with and without stress urinary incontinence (SUI) partners, and to identify predictors of poor sexual function. Methods: A cross-sectional survey was conducted involving sexually active females with or without SUI aged at least 21 years old, and their respective partners....

This study was designed to evaluate the changes of MD and FA in ten patients during stroke evolution over 1 year duration and correlate with clinical and functional assessment.

Objective: To assess the impact of stress urinary incontinence (SUI) on individual components of quality of life (QoL) using both condition-specific and generic questionnaires, and to compare the results of the two instruments with a control group. Methods: Women with or without SUI aged ≥21 years old were recruited. Subjects completed the Inter...

Tocotrienols, the unsaturated form of vitamin E, were reported to modulate platelet aggregation and thrombotic mechanisms in pre-clinical studies. Using a Food and Drug Administration (FDA)-approved cartridge-based measurement system, a randomised, double-blind, crossover and placebo-controlled trial involving 32 metabolic syndrome adults was condu...

Stroke is a major health problem and second leading cause of morbidity and mortality in Malaysia. The application of magnetic resonance (MR) diffusion tensor imaging (DTI) in stroke has evolved considerably over the last decade. During ischaemia, the amount of water within the brain parenchyma i.e. in the neurons (cytotoxic oedema) increases. The i...

Introduction and hypothesis: We evaluated the effects of pulsed magnetic stimulation (PMS) on overall and different aspects of quality of life (QoL) in female patients with stress urinary incontinence (SUI). Methods: This study involved 120 female SUI subjects aged ≥21 years old randomized to either active or sham PMS. Treatment involved two PMS...

Highlights: • Clopidogrel HTPR is frequent among East Asians, regardless of using high LD. • CYP2C19*2 and obesity are associated with clopidogrel HTPR, however, genotyping doesn't predict HTPR efficiently. • Absence or possession of CYP2C19*2 doesn't make clopidogrel responsiveness or HTPR certain. • Haemoglobin and haematocrit interfere with the...

Clopidogrel high on treatment platelets reactivity (HTPR) has burdened achieving optimum therapeutic outcome. Although there are known genetic and non-genetic factors associated with clopidogrel HTPR, which explain in part clopidogrel HTPR, yet, great portion remains unknown, often hindering personalizing antiplatelet therapy. Nuclear magnetic reso...

Introduction and hypothesis: We evaluated patients' perception and satisfaction with nonsurgical pulsed magnetic stimulation (PMS) for treatment of female stress urinary incontinence (SUI) in a randomized, double-blind, sham-controlled trial. Methods: Women with SUI (n = 120) were randomized to either active or sham PMS for 8 weeks (twice/week)....

We prospectively evaluated the effects of pulsed magnetic stimulation (PMS) on sexual function of couples with stress urinary incontinence (SUI) partners. Female SUI subjects received 16 or 32 biweekly PMS sessions depending on treatment response. Prior to, immediately after and at 6-months post-treatment, couples completed the Golombok Rust Invent...

There are errors in the author affiliations. The affiliations should appear as shown here: Teik Hwa Ong1, Ebenezer Chitra2, Srinivasan Ramamurthy3, Rajinikanth Paruvathanahalli Siddalingam3∗, Kah Hay Yuen4, Stephen Periathamby Ambu1, Fabian Davamani2 1 School of Postgraduate Studies, International Medical University, Bukit Jalil, Kuala Lumpur, Mala...

Propolis obtained from bee hives is a natural substance with antimicrobial properties. It is limited by its insolubility in aqueous solutions; hence ethanol and ethyl acetate extracts of Malaysian propolis were prepared. Both the extracts displayed antimicrobial and anti-biofilm properties against Enterococcus faecalis, a common bacterium associate...

Primer sequences used for quantitative PCR. (DOCX)

Comparative effect of Eth and EA extracts of Malaysian propolis on biofilm formation. Graph depicting the percentage reduction in biofilm mass treated with ethanol or ethyl acetate extracts of Malaysian propolis. E. faecalis was cultured in 96-well plates and allowed to form biofilms in the presence or absence of Eth or EA extracts of Malaysian pro...

Dual antiplatelet therapy of aspirin and clopidogrel is pivotal for patients undergoing percutaneous coronary intervention. However, the variable platelets reactivity response to clopidogrel may lead to outcome failure and recurrence of cardiovascular events. Although many genetic and nongenetic factors are known, great portion of clopidogrel varia...

The current study aimed to further contribute information on intrasubject coefficient of variation (CV) from 43 bioequivalence studies conducted by our center. Consistent with Yuen et al. (2001), current work also attempted to evaluate the effect of different parameters (AUC0-t, AUC0-∞, and Cmax) used in the estimation of the study power. Furthermo...

The aim of the present study was to study the efficiency of different techniques used for nanosizing liposomes. Further, the aim was also to evaluate the effect of process parameters of extrusion techniques used for nanosizing liposomes on the size and size distribution of the resultant liposomes. To compare the efficiency of different nanosizing t...

Purpose: Despite significant differences in success rates between surgical and non-surgical treatments for female stress urinary incontinence (SUI), a few cross-sectional surveys reviewed that most patients still prefer the latter. We evaluated the efficacy of the under-studied non-surgical treatment using pulsed magnetic stimulation (PMS) in fema...

Background/objectives: Evidence shows that tocotrienols potentially reverse various chronic disease progressions caused by the metabolic syndrome. We aimed to investigate the acute effects of a single-dose supplementation of gamma and delta tocotrienols (γδ-T3, 1:4 ratio) compared with those in placebo on the insulinemic, anti-inflammatory and ant...

The objective of the present study was to investigate the influence of the encapsulation efficiency and size of liposome on the oral bioavailability of griseofulvin-loaded liposomes. Griseofulvin-loaded liposomes with desired characteristics were prepared from pro-liposome using various techniques. To study the effect of encapsulation efficiency, t...

Previous studies have reported that tocotrienols (T3) possess many distinct properties such as antioxidant, cardioprotective, neuroprotective, anti-cancer, anti-inflammatory and anti-angiogenic, which are beneficial for the improvement of human health. However, there is limited data available on the safety assessment of T3 compared to tocopherols (...

There is currently no published information on the validity and reliability of the Golombok Rust Inventory of Sexual Satisfaction in the Asian population, which limits its use in this region. Our study aimed to evaluate the psychometric properties of this questionnaire in the Malaysian population. Ten couples were recruited for the pilot testing. T...

Purpose: Studies investigating effects of stress urinary incontinence (SUI) on sexual function of couples are scarce. We prospectively evaluated sexual function of couples, relationship between sexual function and quality of life (QoL), and compared QoL of females with or without SUI. Materials and methods: Sexually active females with or withou...

Aims: To enable the use of the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) and ICIQ-Lower Urinary Tract Symptoms Quality of Life (ICIQ-LUTSqol) in Southeast Asia, we translated and subsequently evaluated their validity (content and discriminant validity), reliability (internal consistency a...

Objectives: This study aimed to prepare Coenzyme Q10 (CoQ10) microparticles using electrospraying technology, and evaluate the in-vitro properties and in-vivo oral bioavailability. Key findings: Electrospraying was successfully used to prepare CoQ10 to enhance its solubility and dissolution properties. In-vitro evaluation of the electrosprayed m...

Clopidogrel is an antiplatelet drug which is crucial for coronary artery disease (CAD) patients undergoing interventional angiographic procedure, particularly those with stent placement. However, clopidogrel use is hindered by patients' variable response. Patients with clopidogrel high on treatment platelets reactivity (HTPR) might have recurrence...

Amphotericin B (AmB) is poorly absorbed from the gastrointestinal tract. Recent studies have suggested enhanced drug absorption from solid lipid nanoparticles (SLN). Little is known of the fate of AmB absorption within the gastrointestinal tract, and no gastrointestinal transit study has yet been performed on AmB-containing nano-formulations. We ai...

There is currently a lack of randomized, sham-controlled trials that are adequately powered, using validated outcomes, to allow for firm recommendations on the use of magnetic stimulation for stress urinary incontinence. We report a protocol of a multicenter, randomized, double-blind, sham-controlled parallel-group trial to evaluate the efficacy of...

Abstract The present study was conducted to investigate the enhancing effect of different polymeric carriers on solubility and hence oral bioavailability of artemisinin, a poorly water-soluble drug. Freeze-dried powder preparations of artemisinin and various carriers (polyvinyl pyrrolidone K-25 (PVP K-25), Hydroxypropyl Cellulose (HPC) and dextrin)...

The gastrointestinal (GI) transit behavior of and absorption from an amphotericin B (AmB) solid lipid nanoformulation (SLN) in rats was investigated. We aimed to estimate the gastric emptying time (GET) and cecal arrival time (CAT) of AmB SLN in rats as animal models. From these two parameters, an insight on the absorption window of AmB was ascerta...

Artemisinin (ART) is an oral antimalarial agent with poor aqueous solubilityand low oral bioavailability. The present study describes the preparation of artemisinin freeze dried powder using different carriers (polyvinyl pyrolidone K-25 (PVP K-25), hydroxyl propyl cellulose (HPC) and dextrin) designed to enhance the solubility of artemisinin. and h...

Background: Vitamin B12-deficiency in Type 2 diabetes patients has been strongly associated with metformin treatment. The prevalence varied from 3% to 33%, due to varied definitions of B12-deficiency and diet. In Malaysia, vitamin B12 is prescribed to patients showing symptoms of neuropathy while B12-deficiency screening is not a routine clinical p...

Clopidogrel antiplatelet drug is limited by variable response among patients. This leads to poor patient outcome on treatment platelets reactivity (HTPR). Finding putative biomarkers of HTPR might aid to individualise antiplatelet therapy. Pharmacometabonomics metabolic finger printing (metabotyping) of urine samples using nuclear magnetic resonanc...

Prescribing clopidogrel antiplatelet drug is mitigated by high on treatment platelets reactivity (HTPR) which might lead to therapeutic failure. The HTPR is multifactorial of genetic and non-genetic factors. Prediction of patient's clopidogrel response will assist better personalisation of therapy. Pharmacometabonomics analysis using nuclear magnet...

The present study was conducted to investigate the enhancing effect of different polymeric carriers on solubility and hence oral bioavailability of artemisinin, a poorly water-soluble drug. Freeze-dried powder preparations of artemisinin and various carriers (polyvinyl pyrrolidone K-25 (PVP K-25), Hydroxypropyl Cellulose (HPC) and dextrin) were obt...

Objective: The immune system has been implicated as one mechanism underlying the benefits of acupuncture therapy. Evidence suggests that acupuncture can ameliorate symptoms of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), but the association between clinical response and the immune system has not been investigated. Design/setting:...

AimsTo review whether patients with urinary incontinence (UI) treated with magnetic stimulation (MS) have a higher continence rate compared to sham.Methods Computerized search of electronic databases was performed using the keywords magnetic stimulation therapy and urinary incontinence. Inclusion criteria were randomized, blinded and sham-controlle...

Pelletized dosage forms can be prepared by different methods which, in general, are time consuming and labor intensive. The current study was carried out to investigate the feasibility of preparing the spherical pellets of omeprazole by sieving-spheronization. An optimized formulation was also prepared by extrusion-spheronization process to compare...

The objective of this study was to assess the bioequivalence between the omeprazole laboratory based formulation and the commercial formulation, Zimor Rubio, Spain, considered as reference formulation. The experiment was carried out according to a 2-period, 2-sequence crossover design with a two week washout period. A validated high performance liq...

Previous cell-based and animal studies showed mixed tocotrienols are neuroprotective, but the effect is yet to be proven in humans. Thus, the present study aimed to evaluate the protective activity of mixed tocotrienols in humans with white matter lesions (WMLs). WMLs are regarded as manifestations of cerebral small vessel disease, reflecting varyi...

Nonalcoholic fatty liver disease (NAFLD) is one of the commonest liver disorders. Obesity, insulin resistance, lipid peroxidation and oxidative stress have been identified amongst the possible hits leading to the onset and progression of this disease. Nutritional evaluation of NAFLD patients showed a lower-than-recommended intake of vitamin E. Vita...

Electrophoretic separation was first demonstrated in the year of 1807 and has since been a staple tool used by biologists and chemists for more than a century since its inception. From the initial crude paper electrophoresis system to today's modern automated electrophoresis system, the development of electrophoresis systems have been driven by the...

DNA, RNA and protein isolation is essential in the expansion of science related to the study of these biomolecules. Extraction and purification science has since advanced so rapidly but there seems to be of the same direction in the usage of materials for the capture and containment of biomolecules.There has not been very little attempt to use a bi...

Artemisinin, a poorly water-soluble antimalarial drug, presents a low and erratic bioavailability upon oral administration. The aim of this work was to study an agglomerated powder dosage form for oral administration of artemisinin based on the artemisinin/β-cyclodextrin primary microparticles. These primary microparticles were prepared by spray-dr...

Vitamin E, a potent antioxidant consisting of four isomers each (α, β, γ, δ) of tocopherol (T) and tocotrienol (T3), is found naturally in plant oils at different concentrations. In this study, four semi-purified isonitrogenous and isolipidic (10 %) diets containing canola oil, cold-pressed soybean oil, wheat germ oil, or palm fatty acid distillate...

The present study describes the accelerated stability and kinetics of paracetamol and omeprazole pellets formulated by sieving-spheronisation process. Both the formulations, in amber screwcaped glass bottles, were kept for six months at three storage settings having different temperature and relative humidity. The samples were analyzed using revers...