Background: Highlighting the individual, host-vector interactions, and environmental risk factors for knowlesi malaria were consequential toward more focused and effective prevention and control strategies. This study aims to identify the individual, host-vector interactions, and environmental risk factors for Plasmodium knowlesi malaria among at-risk communities in Peninsular Malaysia. Materials and Methods: A case-control study was conducted involving laboratory-confirmed cases of P. knowlesi malaria, while a locality-matched individual with no history of fever and tested negative for malaria was taken as control. Univariate and multiple logistic regression were applied to evaluate the potential risk factors among respondents using IBM SPSS Statistics for Windows, Version 26.0. Results: Results showed higher cases among males as compared to females (76.1% vs. 23.9%). Multiple logistic regression analysis showed being male is 3.51 higher risk (p < 0.001) to become a case. Respondents whose place of work or study is near the forest edge have 44.0% lower risk (p = 0.030), while those living in the Orang Asli village were 56.0% lower risk as compared to the organized village to become a case (p = 0.035). Conclusion: These findings demonstrated that gender emerges as an independent individual risk factor while residing near a forest edge, in an Orang Asli village, or occupying workers' longhouses situated in hilly areas lowered the environmental risk among respondents. These findings attested that alternative directions must be considered in addressing the known risk factors associated with this type of malaria and the design of prevention and control programs should be tailored to the unique characteristics of each population.
Infectious bursal disease is a highly contagious disease in the poultry industry and causes immunosuppression in chickens. Genome-wide regulations of immune response genes of inbred chickens with different genetic backgrounds, following very virulent infectious bursal disease virus (vvIBDV) infection are poorly characterized. Therefore, this study aims to analyse the bursal tissue transcriptome of six inbred chicken lines 6, 7, 15, N, O and P following infection with vvIBDV strain UK661 using strand-specific next-generation sequencing, by highlighting important genes and pathways involved in the infected chicken during peak infection at 3 days post-infection. All infected chickens succumbed to the infection without major variations among the different lines. However, based on the viral loads and bursal lesion scoring, lines P and 6 can be considered as the most susceptible lines, while lines 15 and N were regarded as the least affected lines. Transcriptome profiling of the bursa identified 4588 genes to be differentially expressed, with 2985 upregulated and 1642 downregulated genes, in which these genes were commonly or uniquely detected in all or several infected lines. Genes that were upregulated are primarily pro-inflammatory cytokines, chemokines and IFN-related. Various genes that are associated with B-cell functions and genes related to apoptosis were downregulated, together with the genes involved in p53 signalling. In conclusion, bursal transcriptome profiles of different inbred lines showed differential expressions of pro-inflammatory cytokines and chemokines, Th1 cytokines, JAK-STAT signalling genes, MAPK signalling genes, and their related pathways following vvIBDV infection.
A double SAW resonator system was developed as a novel method for gas sensing applications. The proposed system was investigated for hydrogen sensing. Commercial Surface Acoustic Wave (SAW) resonators with resonance frequencies of 433.92 MHz and 433.42 MHz were employed in the double SAW resonator system configuration. The advantages of using this configuration include its ability for remote measurements, and insensitivity to vibrations and other external disturbances. The sensitive layer is composed of functionalized multiwalled carbon nanotubes and polyaniline nanofibers which were deposited on pre-patterned platinum metal electrodes fabricated on a piezoelectric substrate. This was mounted into the DSAWR circuit and connected in parallel. The sensor response was measured as the difference between the resonance frequencies of the SAW resonators, which is a measure of the gas concentration. The sensor showed good response towards hydrogen with a minimum detection limit of 1%.
CHEK2 is a protein kinase that is involved in cell-cycle checkpoint control after DNA damage. Germline mutations in CHEK2 gene have been associated with increase in breast cancer risk. The aim of this study is to identify the CHEK2 gene germline mutations among high-risk breast cancer patients and its contribution to the multiethnic population in Malaysia. We screened the entire coding region of CHEK2 gene on 59 high-risk breast cancer patients who tested negative for BRCA1/2 germline mutations from UKM Medical Centre (UKMMC), Hospital Kuala Lumpur (HKL) and Hospital Putrajaya (HPJ). Sequence variants identified were screened further in case-control cohorts consisting of 878 unselected invasive breast cancer patients (180 Malays, 526 Chinese and 172 Indian) and 270 healthy individuals (90 Malays, 90 Chinese and 90 Indian). By screening the entire coding region of the CHEK2 gene, two missense mutations, c.480A>G (p.I160M) and c.538C>T (p.R180C) were identified in two unrelated patients (3.4%). Further screening of these missense mutations on the case-control cohorts unveiled the variant p.I160M in 2/172 (1.1%) Indian cases and 1/90 (1.1%) Indian control, variant p.R180C in 2/526 (0.38%) Chinese cases and 0/90 Chinese control, and in 2/180 (1.1%) of Malay cases and 1/90 (1.1%) of Malay control. The results of this study suggest that CHEK2 mutations are rare among high-risk breast cancer patients and may play a minor contributing role in breast carcinogenesis among Malaysian population.
Granulomatosis with polyangiitis (GPA), previously Wegener's granulomatosis, requires prompt diagnosis and systemic review to exclude life-threatening disease. However, early diagnosis of orbital GPA may be difficult because anti-neutrophil cytoplasmic antibody (ANCA) and anti-PR3 antibody screening can be negative at presentation and orbital biopsies taken for diagnosis may not show the classic features of GPA. This study was designed to compare GPA with other causes of orbital inflammation and to identify the presenting clinical and imaging features most likely to predict GPA and its systemic spread.
Landfill leachate is one of the most recalcitrant wastes for biotreatment and can be considered a potential source of contamination to surface and groundwater ecosystems. In the present study, Fenton oxidation was employed for degradation of stabilized landfill leachate. Response surface methodology was applied to analyze, model and optimize the process parameters, i.e. pH and reaction time as well as the initial concentrations of hydrogen peroxide and ferrous ion. Analysis of variance showed that good coefficients of determination were obtained (R2 > 0.99), thus ensuring satisfactory agreement of the second-order regression model with the experimental data. The results indicated that, pH and its quadratic effects were the main factors influencing Fenton oxidation. Furthermore, antagonistic effects between pH and other variables were observed. The optimum H2O2 concentration, Fe(II) concentration, pH and reaction time were 0.033 mol/L, 0.011 mol/L, 3 and 145 min, respectively, with 58.3% COD, 79.0% color and 82.1% iron removals.
The current in vitro study was designed to investigate the anti-inflammatory, cytotoxic and antioxidant activities of boesenbergin A (BA), a chalcone derivative of known structure isolated from Boesenbergia rotunda. Human hepatocellular carcinoma (HepG2), colon adenocarcinoma (HT-29), non-small cell lung cancer (A549), prostate adenocarcinoma (PC3), and normal hepatic cells (WRL-68) were used to evaluate the cytotoxicity of BA using the MTT assay. The antioxidant activity of BA was assessed by the ORAC assay and compared to quercetin as a standard reference antioxidant. ORAC results are reported as the equivalent concentration of Trolox that produces the same level of antioxidant activity as the sample tested at 20 µg/mL. The toxic effect of BA on different cell types, reported as IC50, yielded 20.22 ± 3.15, 10.69 ± 2.64, 20.31 ± 1.34, 94.10 ± 1.19, and 9.324 ± 0.24 µg/mL for A549, PC3, HepG2, HT-29, and WRL-68, respectively. BA displayed considerable antioxidant activity, when the results of ORAC assay were reported as Trolox equivalents. BA (20 µg/mL) and quercetin (5 µg/mL) were equivalent to a Trolox concentration of 11.91 ± 0.23 and 160.32 ± 2.75 µM, respectively. Moreover, the anti-inflammatory activity of BA was significant at 12.5 to 50 µM and without any significant cytotoxicity for the murine macrophage cell line RAW 264.7 at 50 µM. The significant biological activities observed in this study indicated that BA may be one of the agents responsible for the reported biological activities of B. rotunda crude extract.
The Malaysian National Health Morbidity Survey III (NHMS III), conducted in 2006, was a cross-sectional household survey of the prevalence of chronic diseases, involving 34,539 respondents of age > or =18 years old, in all states of Malaysia. Data collection was by face-to-face interview. Those who self-professed not to be diabetics underwent finger-prick glucose test following at least 8 hours of fasting. The overall prevalence of diabetes mellitus (known and newly diagnosed) was 11.6%. The Indians had the highest prevalence of 19.9% followed by Malays 11.9% and Chinese 11.4%. The prevalence of people with known diabetes and newly diagnosed diabetes was 7.0% and 4.5% respectively. Impaired Fasting Glycaemia was found to be 4.2%. Majority (73.5%) of the patients used government healthcare facilities for their diabetic care. Usage of insulin alone or in combination was low at 7.2% of patients. Only 45.05% of known diabetics have ever had their eye examined. Amputees formed 4.3% of the patients with known diabetes while 3.4% had suffered a stroke event and 1.6% was on some form of renal replacement therapy.
Study name: National Health and Morbidity Survey (NHMS-2006)
Typhonium flagelliforme (TF) is a tropical plant, traditionally used by the ethnic population of Malaysia for the cure of various cancers. This plant had shown to induce antiproliferative effect as well as apoptosis in cancer cells. However, there is no available information to address that TF affects murine leukemia cells in vitro and in vivo. Here, we investigated in vitro and in vivo effects of TF on murine leukemia WEHI-3 cells. It was found that the growth of leukemia cells in vitro was inhibited by the various extracts of TF. Among these fractions, the dichloromethane (DCM) tuber extracts of TF showed the lowest IC(50) (24.0 ± 5.2 μg/ml) and had demonstrated apoptogenic effect when observed under fluorescent microscope. We investigated the in vivo effects of DCM tuber extracts of TF on murine leukemia cells, and the results showed that the counts of immature granulocytes and monocytes were significantly decreased in peripheral blood of BALB/c leukemia mice after the oral administration of DCM tuber extracts of TF for 28 days with three doses (200, 400 and 800 mg/kg). These results were confirmed by observing the spleen histopathology and morphology of enlarged spleen and liver in leukemia mice when compared with the control. Furthermore, the cell death mechanism in the spleen tissue of treated mice was found via apoptosis.
This study investigated the electrochemical oxidation of stabilized leachate from Pulau Burung semi-aerobic sanitary landfill by conducting laboratory experiments with sodium sulfate Na(2)SO(4) (as electrolyte) and graphite carbon electrodes. The control parameters were influent COD, current density and reaction time, while the responses were BOD removal, COD removal, BOD:COD ratio, color and pH. Na(2)SO(4) concentration was 1 g/L. Experiments were conducted based on a three-level factorial design and response surface methodology (RSM) was used to analyze the results. The optimum conditions were obtained as 1414 mg/L influent COD concentration, 79.9 mA/cm(2) current density and 4 h reaction time. This resulted in 70% BOD removal, 68% COD removal, 84% color removal, 0.04 BOD/COD ratio and 9.1 pH. Electrochemical treatment using graphite carbon electrode was found to be effective in BOD, COD and color removal but was not effective in increasing the BOD/COD ratio or enhancing biodegradability of the leachate. The color intensity of the treated samples increased at low influent COD and high current density due to corrosion of electrode material.
Survival after diagnosis of cancer is one of the major outcome measurements and a key criterion for assessing quality of cancer control related to both the preventive and the therapeutic level. The purpose of this study was to determine the 8-year survival time in Malaysia based on socio-demographic and clinical characteristics. A retrospective study of 472 Malaysian women with breast cancer from the Medical Record Department at University Kebangsaan Malaysia Medical Centre (UKMMC) was therefore performed with survival analysis carried out using the Kaplan-Meier with log-rank test for univariate analysis and Cox-regression for multivariate analysis. Women who had cancer or family history of cancer had a longer 8-year survival time (p = 0.008) compared with others who did not have such a history. Tamoxifen use, positive oestrogen receptor status, and race were prognostic indicators for 8-year survival time (p = 0.036, p = 0.018, p = 0.053, respectively) in univariate analysis. Multivariate analysis showed that being Malays and having no family history of cancer were independent prognostic factors for shorter survival time (p = 0.008, p = 0.012, respectively). In conclusion, being Chinese and having a family history of cancer are predictors of longer survival among the Malaysian breast cancer women.
This study proposed an oil palm by-product as a low-cost adsorbent for the removal of hexavalent chromium [Cr (VI)] from aqueous solution. Adsorption of Cr (VI) by sulphuric acid and heat-treated oil palm fibre was conducted using batch tests. The influence of pH, contact time, initial chromium concentration and adsorbent dosage on the removal of Cr (VI) from the solutions was investigated. The optimum initial pH for maximum uptake of Cr (VI) from aqueous solution was found to be 1.5. The removal efficiency was found to correlate with the initial Cr (VI) concentration, adsorbent dosage as well as the contact time between Cr (VI) and the adsorbent. The adsorption kinetics tested with pseudo first order and pseudo second order models yielded high R(2) values from 0.9254 to 0.9870 and from 0.9936 to 0.9998, respectively. The analysis of variance (ANOVA) showed significant difference between the R(2) values of the two models at 99% confidence level. The Freundlich isotherm (R(2)=0.8778) described Cr (VI) adsorption slightly better than the Langmuir isotherm (R(2)=0.8715). Difficulty in desorption of Cr (VI) suggests the suitability of treated oil palm fibre as a single-use adsorbent for Cr (VI) removal from aqueous solution.
Biomaterial, an essential component of tissue engineering, serves as a scaffold for cell attachment, proliferation, and differentiation; provides the three dimensional (3D) structure and, in some applications, the mechanical strength required for the engineered tissue. Both synthetic and naturally occurring calcium phosphate based biomaterial have been used as bone fillers or bone extenders in orthopedic and reconstructive surgeries. This study aims to evaluate two popular calcium phosphate based biomaterial i.e., hydroxyapatite (HA) and tricalcium phosphate/hydroxyapatite (TCP/HA) granules as scaffold materials in bone tissue engineering. In our strategy for constructing tissue engineered bone, human osteoprogenitor cells derived from periosteum were incorporated with human plasma-derived fibrin and seeded onto HA or TCP/HA forming 3D tissue constructs and further maintained in osteogenic medium for 4 weeks to induce osteogenic differentiation. Constructs were subsequently implanted intramuscularly in nude mice for 8 weeks after which mice were euthanized and constructs harvested for evaluation. The differential cell response to the biomaterial (HA or TCP/HA) adopted as scaffold was illustrated by the histology of undecalcified constructs and evaluation using SEM and TEM. Both HA and TCP/HA constructs showed evidence of cell proliferation, calcium deposition, and collagen bundle formation albeit lesser in the former. Our findings demonstrated that TCP/HA is superior between the two in early bone formation and hence is the scaffold material of choice in bone tissue engineering.
This study was aimed at regenerating autologous elastic cartilage for future use in pediatric ear reconstruction surgery. Specific attentions were to characterize pediatric auricular chondrocyte growth in a combination culture medium and to assess the possibility of elastic cartilage regeneration using human fibrin.
Treatment of articular cartilage lesions remains a clinical challenge. The uses of prosthetic joint replace allograft and/or autograft transplant carry a risk of complications due to infection, loosening of its component, immunological rejection and morbidity at the donor site. There has been an increasing interest in the management of cartilage damages, owing to the introduction of new therapeutic options. Tissue engineering as a method for tissue restoration begins to provide a potential alternative therapy for autologous grafts transplantations. We aimed to evaluate how well a tissue engineered neocartilage implant, consist of human articular chondrocytes cultured with the presence of autologous serum and mixed in a fresh fibrin derived from patient, would perform in subcutaneous implantation in athymic mice.
Helicobacter pylori infection of a distinct subtype of cagA may lead to different pathological manifestation. The aim of this study is to determine the presence of cagA gene and its variants in H. pylori infection among different ethnic groups and its effect on gastroduodenal diseases. Overall detection of cagA among the 205 clinical isolates of H. pylori was 94%. Variations in size of the 3' region of cagA gene were examined among 192 Malaysian H. pylori cagA-positive strains. Results showed that three cagA variants differing in fragment length of PCR products were detected and designated as type A (621-651bp), type B (732-735bp) and type C (525 bp). Although there was no association between any of the cagA subtypes with peptic ulcer disease (p>0.05), an association between cagA subtypes with a specific ethnic group was observed. Specific-cagA subtype A strains were predominantly isolated from Chinese compared to Malays and Indians (p<0.0005), and cagA subtype B strains were predominantly isolated from Malays and Indians compared to Chinese (p<0.05). The cagA type A strains of H. pylori is commonly found in the Chinese patients who have a higher risk of peptic ulcer disease, thus indicating that it could be used as an important clinical biomarker for a more severe infection.
Cryptosporidium, a protozoan parasite, can cause cryptosporidiosis which is a gastrointestinal disease that can infect humans and livestock. Cattle are the most common livestock that can be infected with this protozoan. This study was carried out to determine the prevalence of Cryptosporidium infection in cattle in Kuantan, Pahang, Malaysia and to find out the association between the occurrence of infection and 3 different ages of cattle (calves less than 1 year, yearling, and adult cattle). The samples were processed by using formol-ether concentration technique and stained by modified Ziehl Neelsen. The results showed that 15.9% (24/151) of cattle were positive for Cryptosporidium oocysts. The occurrence of Cryptosporidium in calves less than 1 year was the highest with the percentage of 20.0% (11/55) followed by yearling and adult cattle, with the percentage occurrence of 15.6 % (7/45) and 11.8% (6/51), respectively. There was no significant association between the occurrence and age of cattle and presence of diarrhea. Good management practices and proper hygiene management must be taken in order to reduce the infection. It is highly important to control the infection since infected cattle may serve as potential reservoirs of the infection to other animals and humans, especially animal handlers.
Parkinson's disease (PD) is the second most common chronic and progressive neurodegenerative disorder. Its etiology remains elusive and at present only symptomatic treatments exists. Helicobacter pylori chronically colonizes the gastric mucosa of more than half of the global human population. Interestingly, H. pylori positivity has been found to be associated with greater of PD motor severity. In order to investigate the underlying cause of this association, the Sengenics Immunome protein array, which enables simultaneous screening for autoantibodies against 1636 human proteins, was used to screen the serum of 30 H. pylori-seropositive PD patients (case) and 30 age- and gender-matched H. pylori-seronegative PD patients (control) in this study. In total, 13 significant autoantibodies were identified and ranked, with 8 up-regulated and 5 down-regulated in the case group. Among autoantibodies found to be elevated in H. pylori-seropositive PD were included antibodies that recognize Nuclear factor I subtype A (NFIA), Platelet-derived growth factor B (PDGFB) and Eukaryotic translation initiation factor 4A3 (eIFA3). The presence of elevated autoantibodies against proteins essential for normal neurological functions suggest that immunomodulatory properties of H. pylori may explain the association between H. pylori positivity and greater PD motor severity.
Multiplex polymerase chain reaction (PCR) using multiple tandem forward primers and a common reverse primer (MPTP) was recently established as a comprehensive screening method for mutations in X-linked recessive diseases. In the work reported here, MPTP was used to scan for mutations of the glucose-6-phosphate dehydrogenase (G6PD) gene. Mutations in exons 3,4,5,6,7,9, 11, and 12 of the G6PD gene were screened by MPTP in 93 unrelated Malaysian patients with G6PD deficiency. Of the 93 patients, 80 (86%) had identified mutations. Although all of these were missense mutations, identified nucleotide changes were heterogeneous, with 9 mutations involving various parts of the exons. These 9 mutations were G-to-A nucleotide changes at nucleotide 871 of the G6PD gene (G871A), corresponding to G6PD Viangchan, G6PD Mediterranean (C563T), G6PD Vanua Lava (T383C), G6PD Coimbra (C592T), G6PD Kaiping (G1388A), G6PD Orissa (C131G), G6PD Mahidol (G487A), G6PD Canton (G1376T), and G6PD Chatham (G1003A). Our results document heterogeneous mutations of the G6PD gene in the Malaysian population.
OBJECTIVES: The objectives of this study were to investigate the prevalence of factor V Leiden mutation in Malay women with recurrent spontaneous abortion and to clarify the contribution of the factor V Leiden mutation to recurrent miscarriages in these women.
DESIGN: A prospective case control study between June 1999 and April 2000.
SETTING: Hospital University Science of Malaysia, Kubang Kerian, Kelantan, and Maternal and Child Health Clinic, Pasir Mas, Kelantan, Malaysia.
SAMPLES: A total of 46 Malay women with a history of three or more first or second trimester miscarriages were studied. The control group consisted of 46 parous women without obstetric complications.
METHODS: Diagnosis of factor V Leiden mutation was made by examination of factor V Leiden allele product following Mnl I digestion of factor V Leiden alleles amplified by polymerase chain reaction.
RESULTS: None of the 46 women with recurrent spontaneous abortion carried the mutation. Also, we found no subject carrying the factor V Leiden alleles in the control group.
CONCLUSION: These results suggest that that there is no association between the factor V Leiden mutation and recurrent spontaneous abortion in the Malay population.