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Simple instrument for ascending urethrography in males

Ng KK

Med J Malaysia, 1972 Jun;26(4):291-292.
PMID: 35158510

No abstract available.
Goldenhar's syndrome

Fong HC, Vijendran M, Chandran S, Ng KK

Med J Malaysia, 1976 Jun;30(4):299-303.
PMID: 979732
The empty sella syndrome

Anuar M, Ng KK, Chong KF

Med J Malaysia, 1977 Mar;31(3):244-6.
PMID: 904521
Right hydronephrosis and vesicocolic fistula complicating sigmoid colonic diverticulitis: report of a case

Ng KK, Tan KM, Lim KT

Dis Colon Rectum, 1975 Oct;18(7):623-5.
PMID: 1181168
Spatial structure and genetic diversity of two tropical tree species with contrasting breeding systems and different ploidy levels

Ng KK, Lee SL, Koh CL

Mol Ecol, 2004 Mar;13(3):657-69.
PMID: 14871369

Analyses of the spatial distribution pattern, spatial genetic structure and of genetic diversity were carried out in two tropical tree species with contrasting breeding systems and different ploidy levels using a 50-ha demographic plot in a lowland dipterocarp forest in Peninsular Malaysia. Shorea leprosula is a diploid and predominantly outcrossed species, whereas S. ovalis ssp. sericea is an autotetraploid species with apomictic mode of reproduction. Genetic diversity parameters estimated for S. leprosula using microsatellite were consistently higher than using allozyme. In comparisons with S. leprosula and other tropical tree species, S. ovalis ssp. sericea also displayed relatively high levels of genetic diversity. This might be explained by the lower pressure of genetic drift due to tetrasomic inheritance, and for autotetraploids each locus can accommodate up to four different alleles and this allows maintenance of more alleles at individual loci. The observed high levels of genetic diversity in S. ovalis ssp. sericea can also be due to a random retention of more heterogeneous individuals in the past, and the apomictic mode of reproduction might be an evolutionary strategy, which allows the species to maintain high levels of genetic diversity. The spatial distribution pattern analyses of both species showed significant levels of aggregation at small and medium but random distribution at the big diameter-class. The decrease in magnitude of spatial aggregation from small- to large-diameter classes might be due to compensatory mortality during recruitment and survival under competitive thinning process. Spatial genetic structure analyses for both species revealed significant spatial genetic structure for short distances in all the three diameter-classes. The magnitude of spatial genetic structure in both species was observed to be decreasing from smaller- to larger-diameter classes. The high spatial genetic structuring observed in S. ovalis ssp. sericea at the small-diameter class is due primarily to limited seed dispersal and apomictic mode of reproduction. The similar observation in S. leprosula, however, can be explained by limited seed and pollen dispersal, which supports further the fact that the species is pollinated by weak fliers, mainly of Thrips and Megalurothrips in the lowland dipterocarp forest.
Fulltext Development of microsatellites in Labisia pumila (Myrsinaceae), an economically important Malaysian herb

Tnah LH, Lee CT, Lee SL, Ng CH, Ng KK

Appl Plant Sci, 2014 Jun;2(6).
PMID: 25202631 DOI: 10.3732/apps.1400019
Fulltext Isolation and characterization of microsatellite markers for Shorea platyclados (Dipterocarpaceae)

Ng CH, Lee CT, Lee SL, Tnah LH, Ng KK

Appl Plant Sci, 2013 Jul;1(7).
PMID: 25202566 DOI: 10.3732/apps.1200538
Fulltext Evidence for a higher number of species of Odontotermes (Isoptera) than currently known from Peninsular Malaysia from mitochondrial DNA phylogenies

Cheng S, Kirton LG, Panandam JM, Siraj SS, Ng KK, Tan SG

PLoS One, 2011;6(6):e20992.
PMID: 21687629 DOI: 10.1371/journal.pone.0020992

Termites of the genus Odontotermes are important decomposers in the Old World tropics and are sometimes important pests of crops, timber and trees. The species within the genus often have overlapping size ranges and are difficult to differentiate based on morphology. As a result, the taxonomy of Odontotermes in Peninsular Malaysia has not been adequately worked out. In this study, we examined the phylogeny of 40 samples of Odontotermes from Peninsular Malaysia using two mitochondrial DNA regions, that is, the 16S ribosomal RNA and cytochrome oxidase subunit I genes, to aid in elucidating the number of species in the peninsula. Phylogenies were reconstructed from the individual gene and combined gene data sets using parsimony and likelihood criteria. The phylogenies supported the presence of up to eleven species in Peninsular Malaysia, which were identified as O. escherichi, O. hainanensis, O. javanicus, O. longignathus, O. malaccensis, O. oblongatus, O. paraoblongatus, O. sarawakensis, and three possibly new species. Additionally, some of our taxa are thought to comprise a complex of two or more species. The number of species found in this study using DNA methods was more than the initial nine species thought to occur in Peninsular Malaysia. The support values for the clades and morphology of the soldiers provided further evidence for the existence of eleven or more species. Higher resolution genetic markers such as microsatellites would be required to confirm the presence of cryptic species in some taxa.
Fulltext Microsatellite markers of an important medicinal plant, Eurycoma longifolia (Simaroubaceae), for DNA profiling

Tnah LH, Lee CT, Lee SL, Ng KK, Ng CH, Hwang SS

Am J Bot, 2011 May;98(5):e130-2.
PMID: 21613180 DOI: 10.3732/ajb.1000469

Microsatellite markers of an important medicinal plant, Eurycoma longifolia (Simaroubaceae), were developed for DNA profiling and genetic diversity studies.
Fulltext Diagnosis and management of mild cognitive impairment in the community: What is the role of primary care physician?

Ambigga Devi SK, Suthahar A, Ramli AS, Ng KK, Radziah AR, Marymol K

Malays Fam Physician, 2011;6(2-3):74-8.
PMID: 25606229 MyJurnal

Dementia is a large and growing problem in the ageing population but often not diagnosed in its earlier stages which is Mild Cognitive Impairment (MCI). MCI represents the phase between normal ageing and early dementia. About 12% of patients with MCI develop dementia per year, usually Alzheimer's disease. It is a diagnosis given to individuals who have cognitive impairments beyond that is expected for their age and education. However, this condition does not interfere significantly with daily activities as these individuals retain their critical thinking and reasoning skills. Nevertheless, due to its complexity and vague initial presentation, many cases of MCI can be missed. Therefore, it is imperative for primary care physicians to recognise these symptoms as opposed to normal ageing memory changes, and refer these patients to the memory clinic early to confirm the diagnosis. This paper illustrates a common primary care presentation of a patient with MCI. As there is no proven pharmacological treatment for MCI, the mainstay of management is to provide lifestyle intervention and long term support to these patients in the community. Primary care physicians should work as a team with the geriatrician, allied health personnel, support groups and caregivers in providing this care.
Fulltext Prescribing of antihypertensive agents in public primary care clinics - is it in accordance with current evidence?

Ramli AS, Miskan M, Ng K, Ambigga D, Nafiza M, Mazapuspavina M, et al.

Malays Fam Physician, 2010;5(1):36-40.
PMID: 25606184

Large population surveys in Malaysia have consistently shown minimal improvement of blood pressure control rates over the last 10 years. Poor adherence to antihypertensive medication has been recognized as a major reason for poor control of hypertension. This study aimed to describe the prescribing pattern of antihypertensive agents in 2 public primary care clinics and assess its appropriateness in relation to current evidence and guidelines.
Expressed sequence tag-simple sequence repeats isolated from Shorea leprosula and their transferability to 36 species within the Dipterocarpaceae

Ng KK, Lee SL, Tsumura Y, Ueno S, Ng CH, Lee CT

Mol Ecol Resour, 2009 Jan;9(1):393-8.
PMID: 21564660 DOI: 10.1111/j.1755-0998.2008.02238.x

Simple sequence repeats (SSRs) derived from expressed sequence tags (ESTs) are valuable markers because they represent transcribed regions and often transferable to related taxa. Here, we report the development and characterization of EST-SSRs from Shorea leprosula. Fifty-four sequences containing SSRs were identified in 2003 unigenes assembled from 3159 ESTs. Twenty-four EST-SSRs were developed, of which four gave multiple amplifications, five were found to be monomorphic and 15 showed polymorphism, with allele numbers ranging from two to 17 in a single Pasoh Forest Reserve population of 24 individuals. The observed and expected heterozygosities ranged from 0.05 to 0.91 and from 0.16 to 0.93, respectively. Cross-species transferability of the 15 loci to 36 species within Dipterocarpaceae revealed between four and 14 loci that gave positive amplification and 10 loci were found to be transferable to more than 15 species.
Effects of flowering tree density on the mating system and gene flow in Shorea leprosula (Dipterocarpaceae) in Peninsular Malaysia

Fukue Y, Kado T, Lee SL, Ng KK, Muhammad N, Tsumura Y

J Plant Res, 2007 May;120(3):413-20.
PMID: 17387430

Pristine tropical rainforests in Southeast Asia have rich species diversity and are important habitats for many plant species. However, the extent of these forests has declined in recent decades and they have become fragmented due to human activities. These developments may reduce the genetic diversity of species within them and, consequently, the species' ability to adapt to environmental changes. Our objective in the study presented here was to clarify the effect of tree density on the genetic diversity and gene flow patterns of Shorea leprosula Miq. populations in Peninsular Malaysia. For this purpose, we related genetic diversity and pollen flow parameters of seedling populations in study plots to the density of mature trees in their vicinity. The results show that gene diversity and allelic richness were not significantly correlated to the mature tree density. However, the number of rare alleles among the seedlings and the selfing rates of the mother trees were negatively correlated with the density of the adult trees. Furthermore, in a population with high mature tree density pollination distances were frequently <200 m, but in populations with low adult tree density the distances were longer. These findings suggest that the density of flowering trees affects selfing rates, gene flow and, thus, the genetic diversity of S. leprosula populations. We also found an individual S. leprosula tree with a unique reproductive system, probably apomictic, mating system.
Fulltext Intracellular Delivery of Proteins via Fusion Peptides in Intact Plants

Ng KK, Motoda Y, Watanabe S, Sofiman Othman A, Kigawa T, Kodama Y, et al.

PLoS One, 2016;11(4):e0154081.
PMID: 27100681 DOI: 10.1371/journal.pone.0154081

In current plant biotechnology, the introduction of exogenous DNA encoding desired traits is the most common approach used to modify plants. However, general plant transformation methods can cause random integration of exogenous DNA into the plant genome. To avoid these events, alternative methods, such as a direct protein delivery system, are needed to modify the plant. Although there have been reports of the delivery of proteins into cultured plant cells, there are currently no methods for the direct delivery of proteins into intact plants, owing to their hierarchical structures. Here, we demonstrate the efficient fusion-peptide-based delivery of proteins into intact Arabidopsis thaliana. Bovine serum albumin (BSA, 66 kDa) was selected as a model protein to optimize conditions for delivery into the cytosol. The general applicability of our method to large protein cargo was also demonstrated by the delivery of alcohol dehydrogenase (ADH, 150 kDa) into the cytosol. The compatibility of the fusion peptide system with the delivery of proteins to specific cellular organelles was also demonstrated using the fluorescent protein Citrine (27 kDa) conjugated to either a nuclear localization signal (NLS) or a peroxisomal targeting signal (PTS). In conclusion, our designed fusion peptide system can deliver proteins with a wide range of molecular weights (27 to 150 kDa) into the cells of intact A. thaliana without interfering with the organelle-targeting peptide conjugated to the protein. We expect that this efficient protein delivery system will be a powerful tool in plant biotechnology.
Fulltext Population genetics of Intsia palembanica (Leguminosae) and genetic conservation of Virgin Jungle Reserves in Peninsular Malaysia

Lee SL, Ng KK, Saw LG, Norwati A, Salwana MH, Lee CT, et al.

Am J Bot, 2002 Mar;89(3):447-59.
PMID: 21665641 DOI: 10.3732/ajb.89.3.447

A field survey of Virgin Jungle Reserve (VJR) compartments in Peninsular Malaysia allowed us to identify six populations of Intsia palembanica for this study. These were Pasoh Forest Reserve (FR) (Pasoh), Sungai Lalang FR (Lalang), Bukit Lagong FR (Lagong), Bubu FR (Bubu), Bukit Kinta FR (Kinta), and Bukit Perangin FR (Perangin). About 40 adult individuals were sampled in each population. In addition, progeny arrays were collected from nine mother plants at Lagong for a mating system study. A total of nine allozymes, encoded by 14 putative gene loci, were consistently resolved in I. palembanica. The mating system study showed that the species exhibited a mixed-mating system, with multilocus outcrossing rate of 0.766. The levels of diversity were comparably high (mean number of alleles per polymorphic locus = 2.4, mean effective number of alleles per polymorphic locus = 1.64, and mean expected heterozygosity (H(e)) = 0.242), and the majority of the diversity was partitioned within population (G(ST) = 0.040 and F(ST) = 0.048). Significant levels of inbreeding were detected in Bubu and Perangin. Probability tests of recent effective population size reduction using the Infinite Allele Model showed the occurrence of genetic bottlenecks on Lalang and Kinta. Two genetically unique populations (Pasoh and Perangin) were inferred using jackknife analysis. By using the neutral mutation rates, effective population size (N(e)) to maintain the H(e) was 80-800 000 individuals. A simulation study based on pooled samples, however, circumscribed the N(e) to 200 and 210 individuals. Implications of the study for managing the species and the VJRs are discussed.
Fulltext Phylogeographical pattern and evolutionary history of an important Peninsular Malaysian timber species, Neobalanocarpus heimii (Dipterocarpaceae)

Tnah LH, Lee SL, Ng KK, Lee CT, Bhassu S, Othman RY

J Hered, 2013 Jan-Feb;104(1):115-26.
PMID: 23132907 DOI: 10.1093/jhered/ess076

Tectonic movements, climatic oscillations, and marine transgressions during the Cenozoic have had a dramatic effect on the biota of the tropical rain forest. This study aims to reveal the phylogeography and evolutionary history of a Peninsular Malaysian endemic tropical timber species, Neobalanocarpus heimii (Dipterocarpaceae). A total of 32 natural populations of N. heimii, with 8 samples from each population were investigated. Fifteen haplotypes were identified from five noncoding chloroplast DNA (cpDNA) regions. Overall, two major genealogical cpDNA lineages of N. heimii were elucidated: a widespread southern and a northern region. The species is predicted to have survived in multiple refugia during climatic oscillations: the northwestern region (R1), the northeastern region (R2), and the southern region (R3). These putative glacial refugia exhibited higher levels of genetic diversity, population differentiation, and the presence of unique haplotypes. Recolonization of refugia R1 and R2 could have first expanded into the northern region and migrated both northeastwards and northwestwards. Meanwhile, recolonization of N. heimii throughout the southern region could have commenced from refugia R3 and migrated toward the northeast and northwest, respectively. The populations of Tersang, Pasir Raja, and Rotan Tunggal exhibited remarkably high haplotype diversity, which could have been the contact zones that have received an admixture of gene pools from the northerly and also southerly regions. As a whole, the populations of N. heimii derived from glacial refugia and contact zones should be considered in the conservation strategies in order to safeguard the long-term survival of the species.
Fulltext Large-scale collection of full-length cDNA and transcriptome analysis in Hevea brasiliensis

Makita Y, Ng KK, Veera Singham G, Kawashima M, Hirakawa H, Sato S, et al.

DNA Res, 2017 Apr 01;24(2):159-167.
PMID: 28431015 DOI: 10.1093/dnares/dsw056

Natural rubber has unique physical properties that cannot be replaced by products from other latex-producing plants or petrochemically produced synthetic rubbers. Rubber from Hevea brasiliensis is the main commercial source for this natural rubber that has a cis-polyisoprene configuration. For sustainable production of enough rubber to meet demand elucidation of the molecular mechanisms involved in the production of latex is vital. To this end, we firstly constructed rubber full-length cDNA libraries of RRIM 600 cultivar and sequenced around 20,000 clones by the Sanger method and over 15,000 contigs by Illumina sequencer. With these data, we updated around 5,500 gene structures and newly annotated around 9,500 transcription start sites. Second, to elucidate the rubber biosynthetic pathways and their transcriptional regulation, we carried out tissue- and cultivar-specific RNA-Seq analysis. By using our recently published genome sequence, we confirmed the expression patterns of the rubber biosynthetic genes. Our data suggest that the cytoplasmic mevalonate (MVA) pathway is the main route for isoprenoid biosynthesis in latex production. In addition to the well-studied polymerization factors, we suggest that rubber elongation factor 8 (REF8) is a candidate factor in cis-polyisoprene biosynthesis. We have also identified 39 transcription factors that may be key regulators in latex production. Expression profile analysis using two additional cultivars, RRIM 901 and PB 350, via an RNA-Seq approach revealed possible expression differences between a high latex-yielding cultivar and a disease-resistant cultivar.
Mating system and seed variation of Acacia hybrid (A. mangium x A. auriculiformis)

Ng CH, Lee SL, Ng KK, Muhammad N, Ratnam W

J Genet, 2009 Apr;88(1):25-31.
PMID: 19417541

The mating system and seed variation of Acacia hybrid (A. mangium x A. auriculiformis) were studied using allozymes and random amplified polymorphic DNA (RAPD) markers, respectively. Multi-locus outcrossing rate estimations indicated that the hybrid was predominantly outcrossed (mean+/- s.e. t(m) = 0.86+/-0.01). Seed variation was investigated using 35 polymorphic RAPD fragments. An analysis of molecular variance (AMOVA) revealed the highest genetic variation among seeds within a pod (66%-70%), followed by among pods within inflorescence (29%-37%), and the least variation among inflorescences within tree (1%). In addition, two to four RAPD profiles could be detected among seeds within pod. Therefore, the results suggest that a maximum of four seeds per pod could be sampled for the establishment of a mapping population for further studies.
The impact of music guided deep breathing exercise on blood pressure control - A participant blinded randomised controlled study

Kow FP, Adlina B, Sivasangari S, Punithavathi N, Ng KK, Ang AH, et al.

Med J Malaysia, 2018 08;73(4):233-238.
PMID: 30121686 MyJurnal

INTRODUCTION: As pharmacological treatment of hypertension has become a burden worldwide, the study looked into nonpharmacological ways of reducing blood pressure. The objective was to determine if music guided, slow and deep breathing will reduce the blood pressure among patients with hypertension in eight weeks.
METHODS: A participant blinded, multi-centre, randomised controlled trial was conducted in which the participants in the intervention group (IG) practiced deep breathing exercise guided by sound cues and those in the control group (CG) listened to the music. The primary end point was reduction in blood pressure at eight weeks.
RESULTS: 87 patients, 46 males and 41 females with mean age of 61.1 years were recruited and 93.1% of them successfully completed the study. There was significant reduction in systolic and diastolic Blood Pressure from baseline by 8 weeks in both groups. The reduction in Mean systolic blood pressure (SBP) in the control arm was 10.5mmHg compared to 8.3mmHg (p<0.001) in intervention group. Diastolic blood pressure (DBP) reduction in control and intervention groups were 5.2 mmHg (p<0.001) and 5.6 mmHg (p<0.001) respectively. The absolute difference in SBP reduction from baseline in IG & CG was -2.2 (95%CI: -7.8 to 3.5) and DBP was -0.4 (95%CI: -2.9 to 3.6). However, blood pressure reduction between the two groups was not significant.
CONCLUSIONS: Both listening to music and deep breathing exercise were associated with a clinically significant reduction in SBP and DBP. However, deep breathing exercise did not augment the benefit of music in reducing BP.
Fulltext The use of dual oxygen concentrator system for mechanical ventilation during COVID-19 pandemic in Sabah, Malaysia

Cheah PK, Steven EM, Ng KK, Hashim MI, Abdul Kadir MH, Roder NP

Int J Emerg Med, 2021 May 07;14(1):30.
PMID: 33962581 DOI: 10.1186/s12245-021-00354-9

Sabah in Malaysian Borneo is among the Malaysian states which reported a high number of detected COVID-19 cases during the current pandemic. Due to geographical challenges and limited resources, clinicians developed novel strategies for managing patients. The use of a dual oxygen concentrator system for mechanical ventilation is one of the innovations developed by retrieval team members from the Emergency Department (ED) of the Sabah Women and Children's Hospital. Due to conditions requiring isolation of patients suspected of or positive for COVID-19, high-risk patients were treated in an ED extension area that lacked central wall oxygen. Direct access to oxygen tanks became the only viable option, but ensuring a continuous supply was laborious. The novel setup described within this paper has been used on intubated patients in the ED extension area with moderate to high ventilator settings successfully. This simple setup, designed to meet the limited resources within a pandemic environment, needed only a turbine-driven ventilator, two oxygen concentrators, a 3-way connector, and three oxygen tubing. The application of this setup could potentially save more critically ill patients who are being managed in resource-limited conditions such as in smaller district hospitals or out in the field.

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