Displaying all 14 publications

Abstract:
Sort:
  1. Zhang L, Feng XK, Ng YK, Li SC
    BMC Genomics, 2016 Aug 18;17 Suppl 4:430.
    PMID: 27556418 DOI: 10.1186/s12864-016-2791-2
    BACKGROUND: Accurately identifying gene regulatory network is an important task in understanding in vivo biological activities. The inference of such networks is often accomplished through the use of gene expression data. Many methods have been developed to evaluate gene expression dependencies between transcription factor and its target genes, and some methods also eliminate transitive interactions. The regulatory (or edge) direction is undetermined if the target gene is also a transcription factor. Some methods predict the regulatory directions in the gene regulatory networks by locating the eQTL single nucleotide polymorphism, or by observing the gene expression changes when knocking out/down the candidate transcript factors; regrettably, these additional data are usually unavailable, especially for the samples deriving from human tissues.

    RESULTS: In this study, we propose the Context Based Dependency Network (CBDN), a method that is able to infer gene regulatory networks with the regulatory directions from gene expression data only. To determine the regulatory direction, CBDN computes the influence of source to target by evaluating the magnitude changes of expression dependencies between the target gene and the others with conditioning on the source gene. CBDN extends the data processing inequality by involving the dependency direction to distinguish between direct and transitive relationship between genes. We also define two types of important regulators which can influence a majority of the genes in the network directly or indirectly. CBDN can detect both of these two types of important regulators by averaging the influence functions of candidate regulator to the other genes. In our experiments with simulated and real data, even with the regulatory direction taken into account, CBDN outperforms the state-of-the-art approaches for inferring gene regulatory network. CBDN identifies the important regulators in the predicted network: 1. TYROBP influences a batch of genes that are related to Alzheimer's disease; 2. ZNF329 and RB1 significantly regulate those 'mesenchymal' gene expression signature genes for brain tumors.

    CONCLUSION: By merely leveraging gene expression data, CBDN can efficiently infer the existence of gene-gene interactions as well as their regulatory directions. The constructed networks are helpful in the identification of important regulators for complex diseases.

  2. Loo JSE, Lim SW, Ng YK, Tiong JJL
    Int J Pharm Pract, 2017 Dec;25(6):429-437.
    PMID: 28211115 DOI: 10.1111/ijpp.12352
    OBJECTIVES: To identify factors influencing the decisions of Malaysian first-year pharmacy undergraduate students in private higher education when choosing to pursue a degree in pharmacy as well as their choice of private university.

    METHODS: This cross-sectional study employed a validated, self-administered questionnaire which was administered to 543 first-year pharmacy students from nine different private universities. Factor analysis was utilised to extract key factors from the responses. Descriptive and inferential statistics were used to analyse the data.

    KEY FINDINGS: Eight factors motivating students' decision to study pharmacy emerged from the responses, accounting for 63.8% of the variance observed. Students were primarily motivated by intrinsic interests, with work conditions and profession attributes also exerting significant influence. In terms of choice of private university, nine factors were identified, accounting for 73.8% of the variance observed. The image of the school and university were most influential factors in this context, followed by university safety, programme attributes and financial factors.

    CONCLUSIONS: First-year pharmacy students in the private higher education sector are motivated by intrinsic interest when choosing to study pharmacy over other courses, while their choice of private university is influenced primarily by the image of the school and university.

  3. Chan Mun Wei J, Zhao Z, Li SC, Ng YK
    Comput Biol Chem, 2018 Jun;74:428-433.
    PMID: 29625871 DOI: 10.1016/j.compbiolchem.2018.03.010
    DNA fingerprinting, also known as DNA profiling, serves as a standard procedure in forensics to identify a person by the short tandem repeat (STR) loci in their DNA. By comparing the STR loci between DNA samples, practitioners can calculate a probability of match to identity the contributors of a DNA mixture. Most existing methods are based on 13 core STR loci which were identified by the Federal Bureau of Investigation (FBI). Analyses based on these loci of DNA mixture for forensic purposes are highly variable in procedures, and suffer from subjectivity as well as bias in complex mixture interpretation. With the emergence of next-generation sequencing (NGS) technologies, the sequencing of billions of DNA molecules can be parallelized, thus greatly increasing throughput and reducing the associated costs. This allows the creation of new techniques that incorporate more loci to enable complex mixture interpretation. In this paper, we propose a computation for likelihood ratio that uses NGS (next generation sequencing) data for DNA testing on mixed samples. We have applied the method to 4480 simulated DNA mixtures, which consist of various mixture proportions of 8 unrelated whole-genome sequencing data. The results confirm the feasibility of utilizing NGS data in DNA mixture interpretations. We observed an average likelihood ratio as high as 285,978 for two-person mixtures. Using our method, all 224 identity tests for two-person mixtures and three-person mixtures were correctly identified.
  4. Zhang Y, Liu W, Lin Y, Ng YK, Li S
    BMC Genomics, 2019 Apr 04;20(Suppl 2):186.
    PMID: 30967119 DOI: 10.1186/s12864-019-5470-2
    BACKGROUND: Recent advances in genome analysis have established that chromatin has preferred 3D conformations, which bring distant loci into contact. Identifying these contacts is important for us to understand possible interactions between these loci. This has motivated the creation of the Hi-C technology, which detects long-range chromosomal interactions. Distance geometry-based algorithms, such as ChromSDE and ShRec3D, have been able to utilize Hi-C data to infer 3D chromosomal structures. However, these algorithms, being matrix-based, are space- and time-consuming on very large datasets. A human genome of 100 kilobase resolution would involve ∼30,000 loci, requiring gigabytes just in storing the matrices.

    RESULTS: We propose a succinct representation of the distance matrices which tremendously reduces the space requirement. We give a complete solution, called SuperRec, for the inference of chromosomal structures from Hi-C data, through iterative solving the large-scale weighted multidimensional scaling problem.

    CONCLUSIONS: SuperRec runs faster than earlier systems without compromising on result accuracy. The SuperRec package can be obtained from http://www.cs.cityu.edu.hk/~shuaicli/SuperRec .

  5. Daniel DS, Ng YK, Chua EL, Arumugam Y, Wong WL, Kumaran JV
    Microbiol Res, 2013 Oct 1;168(8):485-96.
    PMID: 23706760 DOI: 10.1016/j.micres.2013.04.001
    Studies on the microbial ecology of gut microbiota in bats are limited and such information is necessary in determining the ecological significance of these hosts. Short-nosed fruit bats (Cynopterus brachyotis brachyotis) are good candidates for microbiota studies given their close association with humans in urban areas. Thus, this study explores the gut microbiota of this species from Peninsular Malaysia by means of biochemical tests and 16S rRNA gene sequences analysis. The estimation of viable bacteria present in the stomach and intestine of C. b. brachyotis ranged from 3.06×10(10) to 1.36×10(15)CFU/ml for stomach fluid and 1.92×10(10) to 6.10×10(15)CFU/ml for intestinal fluid. A total of 34 isolates from the stomach and intestine of seven C. b. brachyotis were retrieved. A total of 16 species of bacteria from eight genera (Bacillus, Enterobacter, Enterococcus, Escherichia, Klebsiella, Pantoea, Pseudomonas and Serratia) were identified, Enterobacteriaceae being the most prevalent, contributing 12 out of 16 species isolated. Most isolates from the Family Enterobacteriaceae have been reported as pathogens to humans and wildlife. With the possibility of human wildlife transmission, the findings of this study focus on the importance of bats as reservoirs of potential bacterial pathogens.
  6. Choong SN, Ng YK, Kamalan A, Saraswathy S, Goh EH, Lee MJ, et al.
    Med J Malaysia, 2008 Jul;63 Suppl A:55-6.
    PMID: 19024981
    This study evaluates the effect of maternal age, birth weight and infant sex on two main UCB parameters for use and long-term cryopreservation: TNC and volume. Data from 1000 UCB units were collected and analyzed in this study. The results indicate that TNC is correlated to infant birth weight and sex but not maternal age at delivery. Volume is only correlated to birth weight but not maternal age and infant sex.
  7. Cheah JS, Yeo PP, Lui KF, Tan BY, Tan YT, Ng YK
    Med J Malaysia, 1982 Jun;37(2):141-9.
    PMID: 7132833
    A country-wide diabetic survey of the population (age 15 years and above) of Singapore shows that the prevalence of diabetes mellitus in Singapore is 1.99 percent. It is commoner in males (2.36 percent) than in females (1.64 percent). The prevalence of diabetes in the age group 15-39 years is only 0.40 percent and in the age group 40 years and older it is 5.08 percent. The prevalence of diabetes in Indians (6.07 percent) is significantly higher than that in Malays (2.43 percent) and Chinese (1.55 percent). Indian diabetics have an insignifi"cantly higher incidence of positive family of diabetes (12.7 percent) than Malays (10.9 percent) and Chinese (6.5 percent). Obesity was commoner in Malay diabetics (67.4 percent) than in Chinese diabetics (41.6 percent) and Indian diabetics (35.7 percent). The survey shows that 40.4 percent of the diabetics are known while 59.6 percent of the diabetics are newly diagnosed. The majority of the diabetics are treated with oral hypoglycaemic drugs (71.5 percent) and only 4.8 percent are receiving insulin injections. A mong the female diabetics, 63.0 percent have 4 or more pregnancies and large babies at birth are recorded in 12.3 percent. In the newly diagnosed diabetics, 64.3 percent have no symptoms. The complications of the diabetics are hypertension (26.8 percent), nephropathy (9.8 percent), retinopathy (8.5 percent), coronary heart disease (6.1 percent), skin infection (4.6 percent) and neuropathy (3.3 percent). The high prevalence of diabetes among the Indians is likely to be due to a genetic predisposition coupled with an environmental factor (obesity), although this hypothesis is not conclusively demonstrated by the present study.
  8. Ng YK, Shah NM, Loong LS, Pee LT, Chong WW
    J Eval Clin Pract, 2020 Dec;26(6):1638-1647.
    PMID: 31908087 DOI: 10.1111/jep.13346
    RATIONALE, AIMS AND OBJECTIVES: Patient-centred care (PCC) has been increasingly recognized as the standard in current health care, especially when it comes to health communication between patients and health care professionals. The evidence suggests that PCC could potentially improve medication-related outcomes such as medication adherence, disease self-management, and patient-provider relationships. Pharmacists are strategically positioned in the health care system to provide medication management to patients. However, there is a paucity of research regarding PCC in pharmacist-patient consultations. This study aimed to explore the views and experiences of pharmacists and patients on the important aspects of a PCC consultation.

    METHODS: A semistructured interview study was conducted among 17 patients and 18 pharmacists in three tertiary hospitals in Malaysia. All interviews were audiotaped and transcribed verbatim. Themes were developed using a constant comparison approach and thematic analysis.

    RESULTS: Five main themes emerged from the data, namely, achieving mutual understanding, recognizing individuality, communication style, information giving, and medication decision making. For both pharmacists and patients, a PCC consultation should promote mutual understanding and non-judgmental discussions. Communication was an important element to bridge the gap between patients' and pharmacists' expectations. Patients emphasized the importance of emotional aspects of the consultation, while pharmacists emphasized the importance of evidence-based information to support patient engagement and information needs.

    CONCLUSIONS: Comparison of pharmacists' and patients' views provided insight towards important aspects of PCC in pharmacist-patient consultations. It was suggested that PCC is not a one-sided approach but rather a patient-provider collaboration to optimize the consultation. Further research can be done to improve the integration of PCC in the local health care context, including pharmacist consultations.

  9. Ng YK, Shah NM, Loong LS, Pee LT, Hidzir SAM, Chong WW
    Patient Prefer Adherence, 2018;12:615-624.
    PMID: 29731609 DOI: 10.2147/PPA.S159113
    Purpose: This study investigated patients' and pharmacists' attitudes toward concordance in a pharmacist-patient consultation and how patients' attitudes toward concordance relate to their involvement and self-efficacy in decision making associated with medication use.

    Subjects and methods: A cross-sectional study was conducted among patients with chronic diseases and pharmacists from three public hospitals in Malaysia. The Revised United States Leeds Attitudes toward Concordance (RUS-LATCon) was used to measure attitudes toward concordance in both patients and pharmacists. Patients also rated their perceived level of involvement in decision making and completed the Decision Self-Efficacy scale. One-way analysis of variance (ANOVA) and independent t-test were used to determine significant differences between different subgroups on attitudes toward concordance, and multiple linear regression was performed to find the predictors of patients' self-efficacy in decision making.

    Results: A total of 389 patients and 93 pharmacists participated in the study. Pharmacists and patients scored M=3.92 (SD=0.37) and M=3.84 (SD=0.46) on the RUS-LATCon scale, respectively. Seven items were found to be significantly different between pharmacists and patients on the subscale level. Patients who felt fully involved in decision making (M=3.94, SD=0.462) scored significantly higher on attitudes toward concordance than those who felt partially involved (M=3.82, SD=0.478) and not involved at all (M=3.68, SD=0.471; p<0.001). Patients had an average score of 76.7% (SD=14.73%) on the Decision Self-Efficacy scale. In multiple linear regression analysis, ethnicity, number of medications taken by patients, patients' perceived level of involvement, and attitudes toward concordance are significant predictors of patients' self-efficacy in decision making (p<0.05).

    Conclusion: Patients who felt involved in their consultations had more positive attitudes toward concordance and higher confidence in making an informed decision. Further study is recommended on interventions involving pharmacists in supporting patients' involvement in medication-related decision making.

  10. Ng YK, Mohamed Shah N, Loong LS, Pee LT, Chong WW
    PLoS One, 2021;16(10):e0258249.
    PMID: 34618863 DOI: 10.1371/journal.pone.0258249
    BACKGROUND: Patient-centred care (PCC) has been suggested to provide benefits such as improved patient-healthcare provider communication and better disease self-management to patients. The practice of PCC should involve all healthcare professionals, including pharmacists who are well-positioned in providing pharmaceutical care to patients. However, a better understanding of the factors that can affect the practice of PCC in pharmacists' consultations is needed.

    OBJECTIVE: To explore the perceptions of Malaysian hospital pharmacists and patients on the barriers and facilitators of a PCC approach in pharmacist consultations.

    DESIGN: This study employed a qualitative, explorative semi-structured interview design.

    SETTING AND PARTICIPANTS: Interviews were conducted with 17 patients and 18 pharmacists from three tertiary hospitals in Malaysia. The interviews were audiotaped and transcribed verbatim. Emerging themes were developed through a constant comparative approach and thematic analysis.

    RESULTS: Three themes were identified in this study: (i) patient-related factors (knowledge, role expectations, and sociocultural characteristics), (ii) pharmacist-related factors (personalities and communication), and (iii) healthcare institutional and system-related factors (resources, continuity of care, and interprofessional collaboration). Pharmacists and patients mentioned that factors such as patients' knowledge and attitudes and pharmacists' personality traits and communication styles can affect patients' engagement in the consultation. Long waiting time and insufficient manpower were perceived as barriers to the practice of PCC. Continuity of care and interprofessional collaboration were viewed as crucial in providing supportive and tailored care to patients.

    CONCLUSION: The study findings outlined the potential factors of PCC that may influence its implementation in pharmacist consultations. Strategic approaches can be undertaken by policymakers, healthcare institutions, and pharmacists themselves to address the identified barriers to more fully support the implementation of PCC in the pharmacy setting.

  11. Ng YK, Ikeno S, Kadhim Almansoori AK, Muhammad I, Abdul Rahim R
    Microbiol Spectr, 2022 Dec 21;10(6):e0142221.
    PMID: 36314920 DOI: 10.1128/spectrum.01422-21
    Sphingobacterium sp. is a yellowish Gram-negative bacterium that is usually characterized by high concentrations of sphingophospholipids as lipid components. As microbial enzymes have been in high demand in industrial fields in the past few decades, this study hopes to provide significant information on lipase activities of Sphingobacterium sp., since limited studies have been conducted on the Sphingobacterium sp. lipase. A microbe from one collected Artic soil sample, ARC4, was identified as psychrotolerant Sphingobacterium sp., and it could grow in temperatures ranging from 0°C to 24°C. The expression of Sphingobacterium sp. lipase was successfully performed through an efficient approach of utilizing mutated group 3 late embryogenesis abundant (G3LEA) proteins developed from Polypedilum vanderplanki. Purified enzyme was characterized using a few parameters, such as temperature, pH, metal ion cofactors, organic solvents, and detergents. The expressed enzyme is reported to be cold adapted and has the capability to work efficiently under neutral pH (pH 5.0 to 7.0), cofactors like Na+ ion, and the water-like solvent methanol. Addition of nonionic detergents greatly enhanced the activity of purified enzyme. IMPORTANCE The mechanism of action of LEA proteins has remained unknown to many; in this study we reveal their presence and improved protein expression due to the molecular shielding effect reported by others. This paper should be regarded as a useful example of using such proteins to influence an existing expression system to produce difficult-to-express proteins.
  12. Tan ZQ, Ooi EH, Chiew YS, Foo JJ, Ng YK, Ooi ET
    Comput Biol Med, 2024 Oct;181:109061.
    PMID: 39186904 DOI: 10.1016/j.compbiomed.2024.109061
    Sonothrombolysis is a technique that employs the ultrasound waves to break down the clot. Recent studies have demonstrated significant improvement in the treatment efficacy when combining two ultrasound waves of different frequencies. Nevertheless, the findings remain conflicted on the ideal frequency pairing that leads to an optimal treatment outcome. Existing experimental studies are constrained by the limited range of frequencies that can be investigated, while numerical studies are typically confined to spherical microbubble dynamics, thereby restricting the scope of the analysis. To overcome this, the present study investigated the microbubble dynamics caused by the different combinations of ultrasound frequencies. This was carried out using computational modelling as it enables the visualisation of the microbubble behaviour, which is difficult in experimental studies due to the opacity of blood. The results showed that the pairings of two ultrasound waves with low frequencies generally produced stronger cavitation and higher flow-induced shear stress on the clot surface. However, one should avoid the frequency pairings that are integer multipliers of each other, i.e., frequency ratio of 1/3, 1/2 and 2, as they led to resultant wave with low pressure amplitude that weakened the cavitation. At 0.5 + 0.85 MHz, the microbubble caused the highest shear stress of 60.5 kPa, due to its large translational distance towards the clot. Although the pressure threshold for inertial cavitation was reduced using dual-frequency ultrasound, the impact of the high-speed jet can only be realised when the microbubble travelled close to the clot. The results obtained from the present study provide groundwork for deeper understanding on the microbubble dynamics during dual-frequency sonothrombolysis, which is of paramount importance for its optimisations and the subsequent clinical translation.
  13. Cheah JS, Yeo PP, Thai AC, Lui KF, Wang KW, Tan YT, et al.
    Ann Acad Med Singap, 1985 Apr;14(2):232-9.
    PMID: 4037681
    Singapore is a tropical island city-state with a population of 2.4178 million consisting of Chinese (76.7%), Malays (14.7%), Indians (6.4%) and other races (2.2%). A diabetic survey of the adult population, aged 15 years and above, carried out in 1975, shows that the prevalence of diabetes is 1.99%; it is higher in males (2.36%) than in females (1.64%). It occurs mainly in the age group 40 years and above (5.08%) and is uncommon in the age group 15-39 years (0.40%). In males, the highest prevalence of diabetes (7.0%) is in the age group 45-49 years while in females the highest prevalence (7.2%) is in the age group 55-59 years. 43.3% of the diabetics are of normal weight while 44.3% are overweight and 12.4% are underweight. 59.6% of the diabetics are newly diagnosed while 40.4% are known diabetics; 64.3% of the newly diagnosed diabetics have no symptoms. The prevalence of diabetes among the Indians (6.07%) is significantly higher than that in Malays (2.43%) and Chinese (1.55%). Indian diabetics have a slightly higher positive family history of diabetes (12.7%) than Malays (10.9%) and Chinese (6.5%). Obesity is commoner in Malay diabetics (64.7%) than in Chinese (41.6%) and Indians (35.7%). The possible factors leading to the significantly higher prevalence of diabetes among the Indians compared to the other ethnic groups in Singapore are discussed. It is suggested that the Indian gene is susceptible to diabetes (diabetic genotype) and increased food consumption, altered lifestyle and greater obesity leads to the expression of diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)
  14. Ng YK, Shah NM, Chen TF, Loganadan NK, Kong SH, Cheng YY, et al.
    Explor Res Clin Soc Pharm, 2023 Sep;11:100325.
    PMID: 37694168 DOI: 10.1016/j.rcsop.2023.100325
    BACKGROUND: Effective communication that integrates the value of patient-centered care is important in healthcare encounters. Communication skills training (CST) has been indicated as effective in improving patient-centered communication behaviors. However, there is a paucity of studies on the impact of CST among Malaysian hospital pharmacists.

    OBJECTIVE: This study aimed to evaluate the effects of a patient-centered CST program on patient-centered communication scores, communication self-efficacy, and attitudes toward concordance among pharmacists in public hospitals.

    METHODS: A communication skills training (CST) program was conducted among hospital pharmacists. This training intervention was developed based on patient-centered communication frameworks and techniques, namely the Four Habits Model and motivational interviewing. A pre-test/post-test quasi-experimental design was implemented for the evaluation. Pharmacists underwent pre-test/post-test audiotaped simulated consultations and completed questionnaires, including the Revised United States-Leeds Attitudes Toward Concordance scale (RUS-LATCon) and Communication Self-Efficacy scale. The Four Habits Coding Scheme (FHCS) was used to evaluate patient-centered communication scores from the audiotapes, and the Wilcoxon signed-rank test was used to analyze for differences in the pre- and post-intervention scores.

    RESULTS: A total of 38 pharmacists from four tertiary hospitals participated in this study and completed the pre-test. However, due to the impact of COVID-19, only 23 pharmacists completed the post-test data collection. Improvements were noted in the FHCS scores post-training, including items related to exploring patients' concerns, acceptability, and barriers to treatment. Based on the questionnaire, there was an improvement in recognizing patients' needs and potential medication uncertainty and an increase in the overall communication self-efficacy scores after the training.

    CONCLUSIONS: CST may help improve the adoption of patient-centered communication in pharmacists' consultations with patients.

Related Terms
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links