Northeast Peninsular Malaysia Research Articles

Mitochondrial Genetic Diversity of the Freshwater Snail Melanoides tuberculata.

According to geological history, Peninsular Malaysia and Borneo formed at different times and were once connected during Quaternary glaciations. To determine how this history has influenced phylogeography, our study examined the population genetic structure of the tropical freshwater gastropod Melanoides tuberculata across Peninsular Malaysia and Borneo using the sequences from mitochondrial DNA 16S rRNA and cytochrome oxidase subunit I genes (1168bp). In total, 104 specimens were collected from seventeen populations. All mtDNA haplotypes were identified as belonging to two highly divergent lineages, and these lineages were almost allopatric in their distributions. Our study found that the freshwater fauna in Malaysia might be divided into four regions: northeast Peninsular Malaysia, northwest Peninsular Malaysia, south Peninsular Malaysia, and Borneo. The phylogeography of M. tuberculata in Malaysia was shaped by the landforms of Peninsular Malaysia and by the paleo-river systems in the Sunda continental shelf. In addition, our study found that these two lineages in Malaysia have invaded the globe. These results suggest that Malaysia is located in important shipping lanes throughout the world, and the populations of M. tuberculate might be widely distributed throughout the world by shipping.

Traditional and Complementary Medicine Use in Knee Osteoarthritis and its Associated Factors Among Patients in Northeast Peninsular Malaysia.

We sought to determine the prevalence of traditional and complementary medicine (TCM) use for knee osteoarthritis and its associated factors among patients attending a referral hospital in an eastern coastal state of Malaysia. This cross-sectional study included 214 patients with knee osteoarthritis. A universal sampling method was applied to patients who attended the outpatient clinic in Hospital Universiti Sains Malaysia from May 2013 to October 2013. Participants were given a questionnaire to determine their sociodemographic information and a validated Bahasa Malaysia version of the Western Ontario and McMaster Universities Arthritis Index (WOMAC). This questionnaire was used to assess the severity of knee osteoarthritis (i.e., pain, stiffness, and disturbances in daily activity). Over half (57.9%) of patients reported using TCM to treat knee osteoarthritis. Factors associated with TCM use were gender (odd ratio (OR) = 2.47; 95% confidence interval (CI): 1.28-4.77), duration of knee osteoarthritis (OR = 1.51; 95% CI: 1.03-2.23), and the severity of knee pain (OR = 2.56; 95% CI: 1.71-3.86). The prevalence of TCM use among eastern Malaysian patients with knee osteoarthritis was high. Physicians caring for these patients should be aware of these findings so that inquiries regarding TCM use can be made and patients can be appropriately counseled.

Survival Time and Prognostic Factors for Breast Cancer among Women in North-East Peninsular Malaysia

Background:Breast cancer is the most common malignant disease and the leading cause of cancer death among women globally. This study aimed to determine the median survival time and prognostic factors for breast cancer patients in a North-East State of Malaysia.Methods:This retrospective cohort study was conducted from January till April 2017 using secondary data obtained from the state’s cancer registry. All 549 cases of breast cancer diagnosed from 1st January 2007 until 31st December 2011 were selected and retrospectively followed-up until 31st December 2016. Sociodemographic and clinical information was collected to determine prognostic factors.Results:The average (SD) age at diagnosis was 50.4 (11.2) years, the majority of patients having Malay ethnicity (85.8%) and a histology of ductal carcinoma (81.5%). Median survival times for those presenting at stages III and IV were 50.8 (95% CI:25.34, 76.19) and 6.9 (95% CI:3.21, 10.61) months, respectively. Ethnicity (Adj. HR for Malay vs non-Malay ethnicity=2.52; 95% CI: 1.54, 4.13; p<0.001), stage at presentation (Adj. HR for Stage III vs Stage I=2.31; 95% CI: 1.57, 3.39; p<0.001 and Adj. HR for Stage IV vs Stage I=6.20; 95%CI: 4.45, 8.65; p<0.001), and history of surgical treatment (Adj. HR for patients with no surgical intervention=1.95; 95%CI: 1.52, 2.52; p<0.001) were observed to be the statistically significant prognostic factors associated with death caused by breast cancer.Conclusion:The median survival time among breast cancer patients in North-East State of Malaysia was short as compared to other studies. Primary and secondary prevention aimed at early diagnosis and surgical management of breast cancer, particularly among the Malay ethnic group, could improve treatment outcome.

Studies in Southeast Asian Melastoma (Melastomataceae), 3. A new species of Melastoma from Peninsular Malaysia

Melastoma kemamanense is here described as a new species. It is characterised by broad, scabrid leaves, twigs with closely appressed scales, flowers in compact cymes, and anisomorphic stamens. It is similar to Melastoma imbricatum but differs from it by the thickly overlapping hypanthium scales and larger mature fruits. This new species is so far only known from northeast Peninsular Malaysia.

DNA Barcoding Reveals High Cryptic Diversity of the Freshwater Halfbeak Genus Hemirhamphodon from Sundaland.

DNA barcoding of the cytochrome oxidase subunit I (COI) gene was utilized to assess the species diversity of the freshwater halfbeak genus Hemirhamphodon. A total of 201 individuals from 46 locations in Peninsular Malaysia, north Borneo (Sarawak) and Sumatra were successfully amplified for 616 base pairs of the COI gene revealing 231 variable and 213 parsimony informative sites. COI gene trees showed that most recognized species form monophyletic clades with high bootstrap support. Pairwise within species comparisons exhibited a wide range of intraspecific diversity from 0.0% to 14.8%, suggesting presence of cryptic diversity. This finding was further supported by barcode gap analysis, ABGD and the constructed COI gene trees. In particular, H. pogonognathus from Kelantan (northeast Peninsular Malaysia) diverged from the other H. pogonognathus groups with distances ranging from 7.8 to 11.8%, exceeding the nearest neighbor taxon. High intraspecific diversity was also observed in H. byssus and H. kuekanthali, but of a lower magnitude. This study also provides insights into endemism and phylogeographic structuring, and limited support for the Paleo-drainage divergence hypothesis as a driver of speciation in the genus Hemirhamphodon.

Characterisation and Clinical Significance of FLT3-ITD and non-ITD in Acute Myeloid Leukaemia Patients in Kelantan, Northeast Peninsular Malaysia.

Mutations of the FMS-like tyrosine kinase-3 (FLT3) receptor gene may promote proliferation via activation of multiple signaling pathways. FLT3-internal tandem duplication (FLT3-ITD) is the most common gene alteration found in patients diagnosed with acute myeloid leukaemia (AML) and has been associated with poor prognosis. We performed mutational analysis of exons 14-15 and 20 of the FLT3 gene in 54 AML patients using PCR-CSGE (conformational sensitive gel electrophoresis) followed by sequencing analysis to characterise FLT3 mutations in adult patients diagnosed with AML at Hospital USM, Kelantan, Northeast Peninsular Malaysia. FLT3 exon 14-15 mutations were identified in 7 of 54 patients (13%) whereas no mutation was found in FLT3 exon 20. Six ITDs and one non-ITD mutation were found in exon 14 of the juxtamembrane (JM) domain of FLT3. FLT3-ITD mutations were associated with a significantly higher blast percentage (p-value=0.008) and white blood cell count (p-value=0.023) but there was no significant difference in median overall survival time for FLT3-ITD+/FLT3-ITD- within 2 years (p-value=0.374). The incidence of FLT3-ITD in AML patients in this particular region of Malaysia is low compared to the Western world and has a significant association with WBC and blast percentage.

Comparison of water table fluctuation and chloride mass balance methods for recharge estimation in a tropical rainforest climate: a case study from Kelantan River catchment, Malaysia

Estimated groundwater recharge for selected locations in northeast Peninsular Malaysia (North Kelantan River catchment) was determined using the water table fluctuation (WTF) and chloride mass balance (CMB) methods. The WTF method recharge estimates were compared to the CMB method estimates to see if results are similar and the methods can be applied in a humid, tropical region, such as Malaysia. Effective specific yields of 0.18 and 0.16 were obtained for sites which are much lower than values in the literature for use with the WTF method. The WTF gives mean recharge values of 447 and 319 mm/year at PC61 and Wakaf Bharu (WB), respectively. The difference between sites may be attributed to the difference in lithology, whereby less water table fluctuation is observed for finer-grained lower permeability soil or sediment and higher water table fluctuation observed for more granular larger grain soil or sediment. For the site with lower permeability, the time lag between the storm events and water level rise in a well is longer and water does not reach the water table for small storms. Recharge from chloride profile study was estimated through measurement of enrichment of chloride concentration in soil. Rain-fed groundwater direct recharge ranged from 263.3 to 627.7 mm/year in WB and averaged 691.8 mm/year for Pengkalan Chepa. Recharge estimates from unsaturated zone chloride strongly correlate with soil texture, generally and is greater in the coastal area due to a higher percentage of sand content. Parts of the study area located toward the interior of the peninsula showed lower recharge due to the presence of fine-grained sediment. Comparison of methods from different sites indicates that lithologic setting has a significant role in controlling natural recharge rate. The inconsistency observed between recharge value estimated by the WTF and CMB method may in part be due to adsorption/desorption process and ion exchange in the unsaturated soil, which affects the initial assumption that chloride is a conservative tracer.

THE INFLUENCE OF AQUACULTURE ON MODERN FORAMINIFERA AND SEDIMENTS IN THE SETIU ESTUARY AND LAGOON, TERENGGANU, MALAYSIA: A TEMPORAL INVESTIGATION

Foraminifera, grain size, and carbon and nitrogen isotope ratios and abundances were analyzed in surface-sediment samples collected from three floating fish-cage complexes to address how aquaculture has influenced the Setiu estuary and lagoon of northeast peninsular Malaysia. Two currently active floating fish-cage complexes, SET11-S43 and SET11-S40, are located in the semi-enclosed Setiu lagoon, within four km of an inlet connecting to the South China Sea. The sampling areas experience salinities in the 20s, and sediments have mixed agglutinated and calcareous foraminiferal [total] assemblages, generally dominated by Ammonia aff. A. aoteana and Ammobaculites exiguus . The majority of live foraminifera at these sites belong to agglutinated species; percent of live specimens is greater around the SET11-S43 fish-cage complex, likely related to the presence of aquaculture-related organic-rich mud. Percent agglutinated specimens in total assemblages (live + dead) decrease towards the inlet as total assemblage density and diversity increase due to increased salinity. At a recently (1–3 years) abandoned fish-cage complex, SET11-S9A, located in a low salinity (<5) estuarine setting, Miliammina fusca and Am. exiguus dominate total assemblages. Surface-sediment grain-size data indicate that fish-cage-related organic-rich mud underlies SET11-S43 and extends tens of meters to the north with a surrounding sandier substrate, typical of most of the Setiu estuary and lagoon system. SET11-S40 is underlain by generally sandy sediment; organic-rich mud characterizes the lagoon immediately to the north of this fish-cage complex. Percent carbon and nitrogen in sediment exhibit distributional patterns that strongly correlate with the distribution of fish-cage mud. Greater amounts of mud, carbon, and nitrogen in sediment are found to the north of the active lagoonal fish-cage complexes. The δ13C and δ13N signatures of the organic matter in this area are attributed to input from the surrounding mangrove forest, whereas their distribution is a result of the interaction of tidal currents with the physical presence of fish-farm complexes. The environmental influence of the active fish cages at lagoonal site SET11-S40 is minimal as a result of the flushing effects of tidal currents from a nearby inlet. Further north at the SET11-S43 lagoonal fish-cage complex, which receives less marine influence (lower salinity and reduced tidal currents), organic-rich mud has accumulated beneath and to the north of the complex. Foraminiferal and sedimentological data from abandoned estuarine fish-farm complex SET11-S9A are indistinguishable from those of adjacent estuarine sites indicating a rapid return to pre-fish-farm conditions following abandonment.

Holocene coastal response to monsoons and relative sea-level changes in northeast peninsular Malaysia

Sedimentological, geomorphic, and ground penetrating radar (GPR) data are combined with optically stimulated luminescence data to define the Holocene evolution of a coastal system in peninsular Malaysia. The Setiu coastal region of northeast Malaysia comprises five geological and geomorphic units representing distinct evolutionary phases of this coastline. Estimated marine limiting point elevations indicate deposition of an early aggradational shoreline associated with a sea-level elevation of −0.1 to +1.7m (MSLPMVGD datum) between ∼6.8ka and 5.7ka, in agreement with previous sea-level studies from the Malay–Thai peninsula. A hiatus occurs in the record between ∼5.7ka and 3.0ka, possibly due to a relative sea-level oscillation and shoreline erosion. Long-term relative sea-level fall and possible still-stands created strandplains that are interrupted by aggradational to transgressive paleo-barrier and estuary formation corresponding with brief episodes of RSL rise. Analyses of GPR facies and OSL ages suggest annual clinoform deposition, with geometries dictated by variations in ENSO. These data demonstrate the utility of high resolution studies of coastal facies as useful proxy indicators for paleoclimate studies at subdecadal to millennial time-scales.

Epidemiology and Survival of Hepatocellular Carcinoma in North-east Peninsular Malaysia

The incidence of hepatocellular carcinoma (HCC) is relatively high in Southeast Asia. Globally, HCC has a high fatality rate and short survival. The objectives of this retrospective cohort study were to review the epidemiology and survival of HCC patients at a tertiary centre in north-east of Peninsular Malaysia. Subjects were adult HCC patients diagnosed by histopathology or radio-imaging. Secondary liver carcinoma was excluded. Kaplan Meier and multiple Cox proportional hazard survival analyses were used. Only 210 HCC cases from years 1987-2008, were included in the final analysis. The number of cases was increasing annually. The mean age was 55.0 (SD 13.9) years with male:female ratio of 3.7:1. Approximately 57.6% had positive hepatitis B virus, 2.4% hepatitis C virus, 20% liver cirrhosis and 8.1% chronic liver disease. Only 2.9% had family history and 9.0% had frequently consumed alcohol. Most patients presented with abdominal pain or discomfort and had hepatomegaly, 47.9% had an elevated α-fetoprotein level of 800 IU/ml or more, 51.9% had multiple tumors and 44.8% involved multiple liver lobes. Approximately 63.3% were in stage 3 and 23.4% in stage 4, and 82.9% did not receive any treatment. The overall median survival time was 1.9 months (95% confidence interval (CI): 1.5, 2.3). The 1-month, 6-month, 1-year and 2-year survival rates were 71.8%, 23.3%, 13.0% and 7.3% respectively. Significant prognostic factors were Malay ethnicity [Adjusted hazard ratio (AHR) 1.6; 95%CI: 1.0, 2.5; p=0.030], no chemotherapy [AHR 1.7; 95%CI: 1.1, 2.5; p=0.017] and Child-Pugh class C [AHR 2.6; 95%CI: 1.4, 4.9; p=0.002]. HCC in our study affected a wide age range, mostly male, in advanced stage of disease, with no treatment and very low survival rates. Primary prevention should be advocated in view of late presentation and difficulty of treatment. Vaccination of hepatitis virus and avoidance of liver toxins are to be encouraged.

Valuing Fisheries Depreciation in Natural Resource Accounting: The Pelagic Fisheries in Northeast Peninsular Malaysia

In this paper, an approach based onthe net present value method is used to account forthe changes in the value of fisheries resources. Changes in the value of fisheries resources can occurbetween successive years' catch as well as betweencurrent and optimal levels of catch. These changesneed to be accounted for in the national accountingsystem to reflect the `true' net national income thatis sustainable. The approach outlined in this paper isdesirable as it allows the estimation of thedepreciation value of fisheries resource with limitedbiological information. The application of theapproach to the pelagic fisheries in NortheastPeninsular Malaysia (NEPM) showed that the resourcedepreciated in value over most years from 1982 to1993. These depreciations correspond to increasedfishing effort. In addition, pelagic catches in NEPMfrom 1982 to 1993 were lower than the optimal levelsof catch due to overfishing. Thus policies aimed atreducing fishing effort can provide improvement inboth the potentially higher capital values of thefishery resource and the earning potentials of thefishing industry in NEPM.

Why is acute leukemia more common in males? A possible sex-determined risk linked to the ABO blood group genes.

Acute leukemia is more common in males at almost every age, and this fact remains unexplained. A study was carried out in northeast peninsular Malaysia, where the population is predominantly Malay, to examine whether there was a difference in ABO blood group distribution between males and females with acute leukemia (AL). The ABO blood groups of 109 male and 79 female patients with AL (98 ALL, 90 AML) were compared with those of 1019 controls. In the control population, 39.7% were group O. Among males with AL, 39.4% were group O, whereas among females with AL, the proportion was 24.1% (p=0.03). The same trend to a lower proportion of group O among females was seen if the group was divided into adult/pediatric or lymphoblastic/myeloblastic groups, though these differences were not statistically significant. If these findings can be confirmed, they suggest the presence of a "sex-responsive" gene near to the ABO gene locus on chromosome 9, which relatively protects group O women against AL, at least in our population. The existence of such a gene might also partly explain why acute leukemia, and possibly other childhood cancers, are more common in males.

Diabetes mellitus and associated cardiovascular risk factors in north-east Malaysia.

Two thousand five hundred and eight subjects from the state of Kelantan in North-East Peninsular Malaysia were included in this study to determine the prevalence of diabetes mellitus and impaired glucose tolerance and their association with cardiovascular risk factors. The overall prevalence of diabetes mellitus was 10.5% and impaired glucose tolerance was 16.5%. There was no difference in the prevalence of diabetes mellitus between males and females but the prevalence of impaired glucose tolerance was higher in females (19.0%) than in males (11.5%). Subjects with diabetes mellitus were more obese (38.4%) than normal subjects (24.1%). They also had a higher prevalence of hypertension (12.9%) and hypercholesterolaemia (71.9%) than normal subjects. Subjects with impaired glucose tolerance also had a higher prevalence of obesity (35.5%), hypertension (9.0%) and hypercholesterolaemia (63.0%) than normal subjects. In conclusion, the prevalence of diabetes mellitus and impaired glucose tolerance was high and they were associated with a high prevalence of obesity, hypertension and hypercholesterolaemia.

Payar Islands: Its position in the stratigraphic column of northeast Peninsular Malaysia

Payar Islands: Its position in the stratigraphic column of northeast Peninsular Malaysia