Browse publications by year: 2012

  1. Mutee AF, Salhimi SM, Ghazali FC, Aisha AF, Lim CP, Ibrahim K, et al.
    Pak J Pharm Sci, 2012 Oct;25(4):697-703.
    PMID: 23009983
    Acanthaster planci, the crown-of-thorns starfish, naturally endowed with the numerous toxic spines around the dorsal area of its body. Scientific investigations demonstrated several toxico-pharmacological efficacies of A. planci such as, myonecrotic activity, hemorrhagic activity, hemolytic activity, mouse lethality, phospholipase A2 (PLA2) activity, capillary permeability-increasing activity, edema-forming activity, anticoagulant activity and histamine-releasing activity from mast cells. The present study was performed to evaluate the cytotoxic activity of A. planci extracts obtained by different methods of extraction on MCF-7 and HCT-116, human breast and colon cancer cell lines, respectively. Results of the cell proliferation assay showed that PBS extract exhibited very potent cytotoxic activity against both MCF-7 and HCT-116 cell lines with IC(50) of 13.48 μg/mL and 28.78 μg/mL, respectively, while the extracts prepared by Bligh and Dyer method showed moderate cytotoxicity effect against MCF-7 and HCT-116 cell lines, for chloroform extract, IC(50) = 121.37 μg/mL (MCF-7) and 77.65 μg/mL (HCT-116), and for methanol extract, IC(50) = 46.11 μg/mL (MCF-7) and 59.29 μg/mL (HCT-116). However, the extracts prepared by sequential extraction procedure from dried starfish found to be ineffective. This study paves the way for further investigation on the peptide composition in the PBS extract of the starfish to discover potential chemotherapeutic agents.
    MeSH terms: Methanol/chemistry; Animals; Antineoplastic Agents/isolation & purification; Antineoplastic Agents/pharmacology*; Antineoplastic Agents/chemistry; Chloroform/chemistry; Dose-Response Relationship, Drug; Female; Chemical Fractionation/methods; Humans; Solvents/chemistry; Starfish/chemistry*; Inhibitory Concentration 50; HCT116 Cells; Cell Proliferation/drug effects; MCF-7 Cells
  2. Sofian ZM, Abdullah JM, Rahim AA, Shafee SS, Mustafa Z, Razak SA
    Pak J Pharm Sci, 2012 Oct;25(4):831-7.
    PMID: 23010001
    The possible cytotoxic effects of vancomycin and its complex with beta-cyclodextrin (β-CD) on human glial cell line (CRL 8621) were studied accordingly by means of MTS assay. The cultured cells were incubated with various concentrations of vancomycin, β-CD as well as β-CD/vancomycin complex ranging from 4.69 to 300 ug/ml. A linear dose-dependency cytotoxicity followed by hermetic-like biphasic dose-dependence was observed after incubation period of 72 hours. In general, significant increase (p<0.001) of cell proliferation was observed at lower concentrations: <18.75 μg/ml for cells treated with β-CD and their complex while < 9.38 μg/ml for cells treated with vancomycin. In contrary, regardless of the treatments given, significant (p<0.001) reduce in cell survival was found at higher concentrations >150 μg/ml. In particular, 50 % inhibitory in vitro was achieved at the concentrations of 115.95 μg/ml (for β-CD), 116.48 μg/ml (for vancomycin) and 115.44 μg/ml (for β-CD/vancomycin complex).
    MeSH terms: Anti-Bacterial Agents/toxicity*; Anti-Bacterial Agents/chemistry; Cell Line; Cell Survival/drug effects; Chemistry, Pharmaceutical; Dose-Response Relationship, Drug; Drug Carriers*; Humans; Neuroglia/drug effects*; Neuroglia/pathology; Vancomycin/toxicity*; Vancomycin/chemistry; Inhibitory Concentration 50; beta-Cyclodextrins/toxicity*; beta-Cyclodextrins/chemistry
  3. Picco L, Subramaniam M, Abdin E, Vaingankar JA, Chong SA
    Ann Acad Med Singap, 2012 Aug;41(8):325-34.
    PMID: 23010809
    INTRODUCTION: Smoking is one of the leading preventable causes of death throughout the world and can lead to nicotine dependence, particularly when initiated at a young age. This paper describes the prevalence of smoking and nicotine dependence in the adult Singapore resident population, whilst also exploring rates among the major ethnic groups (Chinese, Malay and Indian), different education levels and those with chronic psychiatric and physical comorbidities.

    MATERIAL AND METHODS: The Singapore Mental Health Study (SMHS) is a cross-sectional epidemiological study that was conducted between December 2009 and December 2010. Information on smoking status was assessed using the Composite International Diagnostic Interview version 3.0 (CIDI 3.0) and the Fagerstrom Test for Nicotine Dependence measured nicotine dependence. Socio-demographic information was also collected.

    RESULTS: In total, 6616 respondents participated in the SMHS giving a response rate of 75.9%. We found that 16% of the population were current smokers and 4.5% had nicotine dependence. Current smokers were more likely to be younger (18 to 34 years old), males, Malay and have lower education, whilst males had a 4.6 times higher risk of nicotine dependence to that of females. The prevalence of nicotine dependence was also higher in those with alcohol abuse and those experiencing chronic pain.

    CONCLUSION: The results from this study highlight the important differences in the prevalence of smoking and nicotine dependence among different age groups, gender and ethnicity in Singapore and are important for developing future health policies and targeted preventive strategies.

    MeSH terms: Adolescent; Adult; Aged; China/ethnology; Cross-Sectional Studies; Educational Status; Female; Humans; Indonesia/ethnology; Malaysia/ethnology; Male; Middle Aged; Nicotine*; Risk Factors; Sex Factors; Singapore/epidemiology; Smoking/ethnology; Smoking/epidemiology*; Prevalence; Multivariate Analysis; Epidemiologic Studies; Substance-Related Disorders/ethnology; Substance-Related Disorders/epidemiology*; Substance-Related Disorders/prevention & control; Young Adult
  4. Ghaznavi-Rad E, Neela V, Nor Shamsudin M, Ghasemzadeh Moghaddam H, Tavakol M, van Belkum A, et al.
    Eur J Clin Microbiol Infect Dis, 2012 Dec;31(12):3317-21.
    PMID: 23010901 DOI: 10.1007/s10096-012-1698-3
    Methicillin-resistant Staphylococcus aureus (MRSA) is well known for its epidemicity, with the emergence of new clones on a daily basis. Diversity in the clonal types of MRSA challenges the success of treatment, as different clones respond to different sets of antibiotics. However, the antibiotic susceptibility among the isolates within the same clones is largely unexplored. In a previous study on MRSA epidemiology in Malaysia, we identified six major clonal complexes (ST-239-CC8, ST-1-CC1, ST-188-CC1, ST-22-CC22, ST-7-CC7 and ST-1283-CC8). In the present study, we investigated the antibiotic susceptibility patterns of isolates of different clones. Three hundred and eighty-nine MRSA isolates were subjected to the disc diffusion test, oxacillin minimum inhibitory concentration (MIC) determination and assessment of the distribution of macrolide, lincosamide and streptogramin B (MLS(B)) resistance genes. Thirty-six different antibiotic profiles were observed: 30 (83.3 %) among ST-239, 2 (5.6 %) among ST-1283 and 1 (2.8 %) each for ST-1, ST-7, ST-22 and ST-188. All ST-239 (362, 9 %) isolates were multiple drug-resistant (MDR; resistant to more than three classes of antibiotics) and had oxacillin MICs >256 mg/l. Among the 385 clindamycin-resistant isolates, 375 (96.4 %) illustrated inducible resistance (D-zone-positive), while 10 (2.6 %) showed constitutive resistance. The vast majority of the macrolide-resistant isolates carried the ermA gene (95.1 %), followed by ermC (12.9 %). Diversity in the antibiotic susceptibilities of isolates within the clones emphasises the need for continuous surveillance of MDR strains to prescribe the correct antibiotic rather than empirical treatment. This will likely reduce the emergence of new endemic or epidemic resistant MRSA clones.
    MeSH terms: Anti-Bacterial Agents/pharmacology*; Genotype; Humans; Malaysia/epidemiology; Microbial Sensitivity Tests; Staphylococcal Infections/microbiology*; Staphylococcal Infections/epidemiology; Drug Resistance, Multiple, Bacterial; Methicillin-Resistant Staphylococcus aureus/classification*; Methicillin-Resistant Staphylococcus aureus/drug effects*; Methicillin-Resistant Staphylococcus aureus/genetics; Molecular Typing
  5. Gunaletchumy SP, Teh X, Khosravi Y, Ramli NS, Chua EG, Kavitha T, et al.
    J Bacteriol, 2012 Oct;194(20):5695-6.
    PMID: 23012278
    Helicobacter pylori is the main bacterial causative agent of gastroduodenal disorders and a risk factor for gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT) lymphoma. The draft genomes of 10 closely related H. pylori isolates from the multiracial Malaysian population will provide an insight into the genetic diversity of isolates in Southeast Asia. These isolates were cultured from gastric biopsy samples from patients with functional dyspepsia and gastric cancer. The availability of this genomic information will provide an opportunity for examining the evolution and population structure of H. pylori isolates from Southeast Asia, where the East meets the West.
    MeSH terms: Biopsy; DNA, Bacterial/genetics*; DNA, Bacterial/chemistry*; Dyspepsia/microbiology; Humans; Malaysia; Molecular Sequence Data; Stomach Neoplasms/microbiology; Helicobacter pylori/genetics*; Helicobacter pylori/isolation & purification; Helicobacter Infections/microbiology; Genome, Bacterial*; Sequence Analysis, DNA*
  6. Chan GF, Gan HM, Rashid NA
    J Bacteriol, 2012 Oct;194(20):5716-7.
    PMID: 23012290
    Enterococcus sp. strain C1 is a facultative anaerobe which was coisolated with Citrobacter sp. strain A1 from a sewage oxidation pond. Strain C1 could degrade azo dyes very efficiently via azo reduction and desulfonation in a microaerophilic environment. Here the draft genome sequence of Enterococcus sp. C1 is reported.
    MeSH terms: Anaerobiosis; Azo Compounds/metabolism; DNA, Bacterial/genetics*; DNA, Bacterial/chemistry*; Coloring Agents/metabolism; Molecular Sequence Data; Oxidation-Reduction; Sewage/microbiology; Genome, Bacterial*; Enterococcus/genetics*; Enterococcus/isolation & purification; Enterococcus/physiology; Sequence Analysis, DNA*
  7. Choo SW, Wong YL, Leong ML, Heydari H, Ong CS, Ng KP, et al.
    J Bacteriol, 2012 Oct;194(20):5724.
    PMID: 23012295
    Mycobacterium abscessus is a species of rapidly growing nontuberculous mycobacteria that is frequently associated with opportunistic infections in humans. Here, we report the annotated genome sequence of M. abscessus strain M94, which showed an unusual cluster of tRNAs.
    MeSH terms: DNA, Bacterial/genetics*; DNA, Bacterial/chemistry*; Multigene Family*; Humans; Molecular Sequence Data; Mycobacterium/genetics*; Mycobacterium/isolation & purification; Mycobacterium Infections, Nontuberculous/microbiology; Opportunistic Infections/microbiology; RNA, Bacterial/genetics; RNA, Transfer/genetics*; Genome, Bacterial*; Sequence Analysis, DNA*
  8. Rezayi M, Heng LY, Kassim A, Ahmadzadeh S, Abdollahi Y, Jahangirian H
    Sensors (Basel), 2012;12(7):8806-14.
    PMID: 23012518
    Novel ionophores comprising various hydroxide and amine structures were immobilized onto poly(vinyl chloride) (PVC) matrices, and these were examined to determine Ti(III) selectivity. To predict the selectivity of Ti(III), a PVC membrane was used to investigate the binding of Ti(III) to c-methylcalix[4]resorcinarene (CMCR). The study showed that the chelating ligand, CMCR, was coordinated selectively to Ti(III) at eight coordination sites involving the oxygen atoms at the interface of the membrane/solution. The membrane was prepared, based on CMCR as an ionophore, sodium tetrakis(4-fluorophenyl) borate (NaTFPB) as a lipophilic ionic additive, and dioctylphthalate (DOP) as a plasticizer. The immobilization of the ionophore and surface characterization studies revealed that the performance of CMCR-immobilized PVC was equivalent to that of mobile ionophores in supported liquid membranes (SLMs). The strengths of the ion-ionophore (CMCR-Ti(OH)(OH(2))(5) (2+)) interactions and the role of ionophores on membranes were studied via UV-Vis, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and and X-ray diffraction (XRD).
    MeSH terms: Borates; Diethylhexyl Phthalate; Ionophores; Microscopy, Electron, Scanning; Oxygen; Phenylalanine; Plasticizers; Polyvinyl Chloride; Sodium; Titanium; Vinyl Chloride; X-Ray Diffraction; Spectroscopy, Fourier Transform Infrared; Calixarenes
  9. Yam MF, Ahmad M, Por LY, Ang LF, Basir R, Asmawi MZ
    Sensors (Basel), 2012;12(7):9603-12.
    PMID: 23012561
    The stepping forces of normal and Freund Complete Adjuvant (FCA)-induced arthritic rats were studied in vivo using a proposed novel analgesic meter. An infrared charge-coupled device (CCD) camera and a data acquisition system were incorporated into the analgesic meter to determine and measure the weight of loads on the right hind paw before and after induction of arthritis by FCA injection into the paw cavity. FCA injection resulted in a significant reduction in the stepping force of the affected hind paw. The stepping force decreased to the minimum level on day 4 after the injection and then gradually increased up to day 25. Oral administration of prednisolone significantly increased the stepping forces of FCA-induced arthritic rats on days 14 and 21. These results suggest that the novel device is an effective tool for measuring the arthritic pain in in vivo studies even though walking is a dynamic condition.
    MeSH terms: Administration, Oral; Analgesics; Animals; Arthritis; Foot; Freund's Adjuvant; Pain; Prednisolone; Walking; Rats
  10. Poh YW, Gan SY, Tan EL
    Exp Oncol, 2012 Jul;34(2):85-9.
    PMID: 23013758
    The aim of this study is to investigate whether IL-6, IL-10 and TGF-β are able to confer resistance to apoptosis in nasopharyngeal carcinoma cells by upregulating the expression of survivin.
    MeSH terms: Data Interpretation, Statistical; Dose-Response Relationship, Drug; Humans; Imidazoles/pharmacology; Naphthoquinones/pharmacology; Nasopharyngeal Neoplasms/genetics; Nasopharyngeal Neoplasms/metabolism*; Nasopharyngeal Neoplasms/pathology; Blotting, Western; Interleukin-6/pharmacology*; Interleukin-6/physiology; Gene Expression Regulation, Neoplastic/drug effects*; Transforming Growth Factor beta/pharmacology*; Transforming Growth Factor beta/physiology; Interleukin-10/pharmacology*; Interleukin-10/physiology; Apoptosis/drug effects*; Apoptosis/genetics; Cell Culture Techniques; Reverse Transcriptase Polymerase Chain Reaction; Cell Line, Tumor; Inhibitor of Apoptosis Proteins/antagonists & inhibitors; Inhibitor of Apoptosis Proteins/genetics*
  11. Naidu KR, Kumar KS, Arulselvan P, Reddy CB, Lasekan O
    Arch Pharm (Weinheim), 2012 Dec;345(12):957-63.
    PMID: 23015406 DOI: 10.1002/ardp.201200192
    A series of α-hydroxyphosphonates were synthesized from the reaction of aldehyde (1) with triethylphosphite (2) in the presence of oxone and evaluated for their antioxidant properties against lipid peroxidation, reduced glutathione, superoxide dismutase, and catalase. The majority of the compounds showed promising antioxidant activity. Diethyl anthracen-9-yl (hydroxy) methylphosphonate (3n) is the most potent and biologically active compound against free radicals.
    MeSH terms: Animals; Antioxidants/chemical synthesis*; Antioxidants/pharmacology; Antioxidants/chemistry; Brain/drug effects; Brain/enzymology; Brain/metabolism; Catalase/metabolism; Glutathione/metabolism; Superoxide Dismutase/metabolism; Drug Design*; Lipid Peroxidation/drug effects; Molecular Structure; Biomarkers/analysis; Rats, Wistar; Oxidative Stress/drug effects; Rats; Organophosphonates/chemical synthesis*; Organophosphonates/pharmacology; Organophosphonates/chemistry
  12. Monajemi H, Daud MN, Mohd Zain S, Wan Abdullah WA
    Biochem. Cell Biol., 2012 Dec;90(6):691-700.
    PMID: 23016605 DOI: 10.1139/o2012-027
    Finding a proper transition structure for the peptide bond formation process can lead one to a better understanding of the role of ribosome in catalyzing this reaction. Using computer simulations, we performed the potential energy surface scan on the ester bond dissociation of P-site aminoacyl-tRNA and the peptide bond formation of P-site and A-site amino acids. The full fragments of initiator tRNA(i)(met) and elongator tRNA(phe) are attached to both cognate and non-cognate amino acids as the P-site substrate. The A-site amino acid for all four calculations is methionine. We used ONIOM calculations to reduce the computational cost. Our study illustrates the reduced rate of peptide bond formation for misacylated tRNA(i)(met) in the absence of ribosomal bases. The misacylated elongator tRNA(phe), however, did not show any difference in its PES compared with that for the phe-tRNA(phe). This demonstrates the structural specification of initiator tRNA(i)(met) for the amino acids side chain.
    MeSH terms: Catalysis; Computer Simulation*; Kinetics; Peptides/chemistry*; RNA, Transfer, Amino Acyl/metabolism; RNA, Transfer, Met/metabolism; RNA, Transfer, Met/chemistry*; RNA, Transfer, Phe/metabolism; RNA, Transfer, Phe/chemistry*; Substrate Specificity; Thermodynamics
  13. Khor GL, Misra S
    Asia Pac J Clin Nutr, 2012;21(4):476-86.
    PMID: 23017305
    It is estimated that more than 200 million young children worldwide fail to reach their potential in cognitive development owing to undernutrition. Numerous studies have assessed the effects of micronutrient supplementation on growth and cognitive development in infants, toddlers and preschoolers. However, micronutrient interventions on the cognitive performance of older children are limited. This article seeks to provide an update on micronutrient interventions and cognitive outcomes among children aged 5-15 years in developing countries. A total of 13 randomized controlled trials published since 2000 were identified. Majority of these studies assessed the effects of micronutrient-fortified foods on various domains of cognitive function. Among key micronutrients assessed were iron, zinc, iodine and vitamin A. This review found a lack of consistency in the impact of micronutrient supplementation on intelligence, long term mental functions and school examination grades of the children. A beneficial effect of micronutrient supplementation on short term memory was more consistently reported. Overall, the evidence from this review for the impact of micronutrients on cognitive performance in older children remains equivocal. In light of the growing interest on the influence of nutrition on cognition, it is important that culturally-appropriate and sufficiently sensitive assessment tools be used for measuring the desired cognitive outcomes that are most likely to be affected by the nutrients under study.
    MeSH terms: Adolescent; Child; Child Development*; Child, Preschool; Cognition Disorders/prevention & control*; Developing Countries*; Educational Measurement; Female; Food, Fortified; Humans; Intelligence; Male; Memory, Short-Term; Task Performance and Analysis; Randomized Controlled Trials as Topic; Micronutrients/administration & dosage; Micronutrients/therapeutic use*; Dietary Supplements; Adolescent Development*
  14. Abu Zaid Z, Shahar S, Jamal AR, Mohd Yusof NA
    Asia Pac J Clin Nutr, 2012;21(4):502-10.
    PMID: 23017308
    A randomised trial was carried out to determine the effect of supplementation of fish oil among 51 children with leukaemia aged 4 to 12 years on appetite level, caloric intake, body weight and lean body mass. They were randomly allocated into the trial group (TG) and the control group (CG). At baseline, 30.8% of TG subjects and 44.0% of CG subjects were malnourished and 7.7% of subject from TG and 28.0% from CG were classified as stunted. The majority of subjects from TG and CG were in the mild malnutrition category for mid upper arm muscle circumference (MUAMC)-for-age. The TG group showed significant increment in MUAMC (0.13 cm vs -0.09 cm) compared with CG at 8 weeks (p<0.001). There was a significant higher increase for appetite level (0.12±0.33) (p<0.05) and an increasing trend on energy and protein intake in the TG group (213±554 kcal; 3.64 ±26.8 g) than in the CG group. In conclusion, supplementation of fish oil has a positive effect on appetite level, caloric intake and MUAMC among children with leukaemia.
    MeSH terms: Academic Medical Centers; Arm; Body Weight; Child; Child Development*; Child, Preschool; Dietary Proteins/administration & dosage; Female; Fish Oils/adverse effects; Fish Oils/therapeutic use*; Growth Disorders/complications; Growth Disorders/diet therapy; Growth Disorders/ethnology; Growth Disorders/pathology; Humans; Leukemia/complications*; Malaysia; Male; Patient Dropouts; Malnutrition/complications; Malnutrition/diet therapy*; Malnutrition/ethnology; Malnutrition/pathology; Body Size
  15. Mohamad S, Shuid AN, Mohamed N, Fadzilah FM, Mokhtar SA, Abdullah S, et al.
    Clinics (Sao Paulo), 2012 Sep;67(9):1077-85.
    PMID: 23018307
    OBJECTIVE: Osteoporosis increases the risk of bone fractures and may impair fracture healing. The aim of this study was to investigate whether alpha-tocopherol can improve the late-phase fracture healing of osteoporotic bones in ovariectomized rats.

    METHOD: In total, 24 female Sprague-Dawley rats were divided into three groups. The first group was sham-operated, and the other two groups were ovariectomized. After two months, the right femora of the rats were fractured under anesthesia and internally repaired with K-wires. The sham-operated and ovariectomized control rat groups were administered olive oil (a vehicle), whereas 60 mg/kg of alpha-tocopherol was administered via oral gavage to the alpha-tocopherol group for six days per week over the course of 8 weeks. The rats were sacrificed, and the femora were dissected out. Computed tomography scans and X-rays were performed to assess fracture healing and callus staging, followed by the assessment of callus strengths through the biomechanical testing of the bones.

    RESULTS: Significantly higher callus volume and callus staging were observed in the ovariectomized control group compared with the sham-operated and alpha-tocopherol groups. The ovariectomized control group also had significantly lower fracture healing scores than the sham-operated group. There were no differences between the alpha-tocopherol and sham-operated groups with respect to the above parameters. The healed femora of the ovariectomized control group demonstrated significantly lower load and strain parameters than the healed femora of the sham-operated group. Alpha-tocopherol supplementation was not able to restore these biomechanical properties.

    CONCLUSION: Alpha-tocopherol supplementation appeared to promote bone fracture healing in osteoporotic rats but failed to restore the strength of the fractured bone.

    MeSH terms: Animals; Antioxidants/pharmacology*; Biomechanical Phenomena; Disease Models, Animal; Female; Femur/drug effects; Humans; Ovariectomy; Radiography; Tensile Strength; Time Factors; Bone Density; Tomography Scanners, X-Ray Computed; Fracture Healing/drug effects*; Rats, Sprague-Dawley; Pliability; alpha-Tocopherol/pharmacology*; Fractures, Bone/drug therapy*; Rats
  16. Manuel AM, Kuljit S, Gopalakrishnan G, Suresh KG, Balraj P
    Trop Biomed, 2012 Sep;29(3):360-5.
    PMID: 23018498 MyJurnal
    The purpose of this study is to determine the relevance of the hygiene hypothesis; that is to determine if worm infestation has a protective role against the development of allergic rhinitis. A prospective case controlled study was conducted. Specific IgG levels to Toxocara were studied in 85 patients confirmed to have allergic rhinitis and were compared to levels in another 85 controls, with no form of allergy. The IgG assay was done using ELISA technique. There was a higher incidence of positive specific IgG to Toxocara in the controls as compared to allergic patients. The values were statistically significant [Chi square test (p=0.002)]. This negative association between worm infestation and allergic rhinitis suggests that a previous worm infestation could protect against the development of allergic rhinitis.
    MeSH terms: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Antigens, Helminth/blood; Child; Enzyme-Linked Immunosorbent Assay; Humans; Immunoglobulin E/blood; Immunoglobulin G/blood; Larva Migrans, Visceral/complications; Larva Migrans, Visceral/epidemiology; Larva Migrans, Visceral/parasitology*; Longitudinal Studies; Middle Aged; Occupations; Prospective Studies; Rhinitis, Allergic, Perennial/immunology*; Rhinitis, Allergic, Perennial/parasitology; Incidence; Prevalence; Case-Control Studies; Toxocara canis/immunology*; Young Adult; Rhinitis, Allergic
  17. Mohd-Zain Z, Kamsani NH, Ismail IS, Ahmad N
    Trop Biomed, 2012 Sep;29(3):372-80.
    PMID: 23018500 MyJurnal
    Prior to the implementation of Haemophilus influenzae type b vaccination worldwide, H. influenzae has been one of the main causative agents of community acquired pneumonia and meningitis in children. Due to the lack of information on the characteristics of the H. influenzae isolates that have previously been collected in Malaysia, the H. influenzae were assessed of their microbial susceptibility to commonly used antibiotics. Emphasis was made on strains that were resistance to co-trimoxazole (SXT) and their mode of transfer of the antibiotic resistance determinants were examined. A collection of 34 H. influenzae isolates was serotyped and antimicrobial susceptibility tests were performed to 11 antibiotics. To the isolates that were found to be resistant to co-trimoxazole, minimum inhibition concentration (MIC) to SXT was performed using Etest while agar dilution method was used to measure the individual MICs of trimethoprim (TMP) and sulfamethoxazole (SUL). These isolates were also examined for presence of plasmid by PCR and isolation method. Conjugal transfers of SXT-resistant genes to SXT-susceptible hosts were performed to determine their rate of transfer. Result showed that 20.6% of the total number of isolates was serotype B while the remaining was non-typeable. Antimicrobial susceptibility profile of all the isolates revealed that 58.8% was resistant to at least one antibiotic. Majority of these isolates were equally resistant to ampicillin and tetracycline (29.4% each), followed by resistance to SXT (26.5%). From nine isolates that were found to be SXT-resistant, five contained plasmid/s. Conjugal transfer experiment showed that these five isolates with plasmid transferred SXT-resistance determinants at a higher frequency than those without. From these observations, it is postulated that plasmid is not involved in the transfer of SXT-resistance genes but presence of plasmid facilitates their transfer. The information obtained from this study provides some basic knowledge on the antimicrobial susceptibility pattern of the H. influenzae isolates and their mode of transfer of SXT-resistance genes.
    MeSH terms: Ampicillin/pharmacology; Anti-Bacterial Agents/pharmacology*; Child; DNA, Bacterial/genetics; Haemophilus Infections/drug therapy; Haemophilus Infections/microbiology*; Haemophilus influenzae/drug effects*; Haemophilus influenzae/genetics*; Haemophilus influenzae/immunology; Haemophilus influenzae/isolation & purification; Humans; Malaysia; Microbial Sensitivity Tests; Phenotype; Plasmids/genetics; Serotyping; Tetracycline/pharmacology; Trimethoprim, Sulfamethoxazole Drug Combination/pharmacology*; Community-Acquired Infections/drug therapy; Community-Acquired Infections/microbiology; Pneumonia, Bacterial/drug therapy; Pneumonia, Bacterial/microbiology; Drug Resistance, Multiple, Bacterial
  18. Takaoka H, Srisuka W, Saeung A, Otsuka Y, Choochote W
    Trop Biomed, 2012 Sep;29(3):381-90.
    PMID: 23018501
    Simulium (Nevermannia) chomthongense sp. nov. is described from female, male, pupal and larval specimens collected from Doi Inthanon National Park and Doi Phahompok National Park, Chiang Mai, Thailand. This new species, first reported as S. (Eusimulium) sp. A, and later regarded as S. (N.) caudisclerum Takaoka & Davies, described from peninsular Malaysia, is distinguished from S. (N.) caudisclerum in the male by the number of enlarged upper-eye facets and the relative size of the hind basitarsus against the hind tibia and femur, and in the pupa by the relative length of the stalks of paired filaments against the common basal stalk and the color of the dorsal surface of abdominal segments 1- 3 (or 4). Taxonomic and molecular notes are provided to separate this new species from four other known species of the vernum species-group, which share an accessory sclerite on the larval abdomen, a rare characteristic in this species-group.
    MeSH terms: Animals; Base Sequence; DNA, Mitochondrial/genetics; DNA, Mitochondrial/chemistry; DNA, Ribosomal/genetics; DNA, Ribosomal/chemistry; Female; Larva; Male; Molecular Sequence Data; Pupa; RNA, Ribosomal, 16S/genetics; Simuliidae/anatomy & histology; Simuliidae/classification*; Simuliidae/genetics; Thailand; Sequence Analysis, DNA
  19. Azira NM, Zairi NZ, Amry AR, Zeehaida M
    Trop Biomed, 2012 Sep;29(3):398-404.
    PMID: 23018503 MyJurnal
    Plasmodium knowlesi is a simian malaria parasite and is recently recognized as the fifth malaria parasite infecting humans. Manifestation of the infection may resemble other infection particularly dengue fever leading to inappropriate management and delay in treatment. We reported three cases of naturally acquired P. knowlesi in Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia. Clinical manifestations were quite similar in those cases. Microscopically, the diagnosis might be challenging. These cases were confirmed by polymerase chain reaction method which serves as a gold standard.
    MeSH terms: Adult; Aged; Antimalarials/therapeutic use*; Dengue/diagnosis; Diagnosis, Differential; Fever; Hospitals, Teaching; Humans; Malaria/diagnosis*; Malaria/drug therapy; Malaria/parasitology; Malaysia; Male; Middle Aged; Thrombocytopenia/diagnosis*; Thrombocytopenia/drug therapy; Thrombocytopenia/parasitology; Polymerase Chain Reaction; Plasmodium knowlesi/genetics; Plasmodium knowlesi/isolation & purification*; Tertiary Care Centers
  20. Basir R, Hasballah K, Jabbarzare M, Gam LH, Abdul Majid AM, Yam MF, et al.
    Trop Biomed, 2012 Sep;29(3):405-21.
    PMID: 23018504 MyJurnal
    The involvement of interleukin-18 (IL-18) and the effects of modulating its release on the course of malaria infection were investigated using Plasmodium berghei ANKA infection in ICR mice as a model. Results demonstrated that plasma IL-18 concentrations in malarial mice were significantly elevated and positively correlated with the percentage parasitaemia development. Significant expressions of IL-18 were also observed in the brain, spleen and liver tissues. Slower development of parasitaemia was observed significantly upon inhibition and neutralization of IL-18, whereas faster development of parasitaemia was recorded when the circulating levels of IL-18 were further augmented during the infection. Inhibition and neutralization of IL-18 production also resulted in a significant decrease of plasma concentrations of pro-inflammatory cytokines (TNFα, IFNγ, IL-1α and IL-6), whereas the anti-inflammatory cytokine, IL-10, was significantly increased. Augmenting the release of IL- 18 during the infection on the other hand resulted in the opposite. Early mortality in malarial mice was also observed when the circulating levels of IL-18 were further augmented. Results proved the important role of IL-18 in immune response against malaria and suggest that IL-8 is pro-inflammatory in nature and may involve in mediating the severity of the infection through a pathway of elevating the pro-inflammatory cytokine and limiting the release of anti-inflammatory cytokine.
    MeSH terms: Animals; Antibodies, Monoclonal; Brain/immunology; Gene Expression Regulation; Liver/immunology; Malaria/drug therapy; Malaria/immunology*; Malaria/mortality; Male; Mice, Inbred ICR; Plasmodium berghei/drug effects; Plasmodium berghei/growth & development; Plasmodium berghei/immunology*; Recombinant Proteins; Spleen/immunology; Cytokines/analysis; Cytokines/blood; Cytokines/metabolism*; Parasitemia/drug therapy; Parasitemia/immunology; Parasitemia/mortality; Interleukin-18/analysis; Interleukin-18/metabolism*; Interleukin-18/therapeutic use; Mice
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