Browse publications by year: 2012

  1. Fulltext Ficus deltoidea: A Potential Alternative Medicine for Diabetes Mellitus
    Adam Z, Khamis S, Ismail A, Hamid M
    Evid Based Complement Alternat Med, 2012;2012:632763.
    PMID: 22701507 DOI: 10.1155/2012/632763
    Ficus deltoidea from the Moraceae family has been scientifically proven to reduce hyperglycemia at different prandial states. In this study, we evaluate the mechanisms that underlie antihyperglycemic action of Ficus deltoidea. The results had shown that hot aqueous extract of Ficus deltoidea stimulated insulin secretion significantly with the highest magnitude of stimulation was 7.31-fold (P < 0.001). The insulin secretory actions of the hot aqueous extract involved K(+) (ATP) channel-dependent and K(+) (ATP)-channel-independent pathway. The extract also has the ability to induce the usage of intracellular Ca(2+) to trigger insulin release. The ethanolic and methanolic extracts enhanced basal and insulin-mediated glucose uptake into adipocytes cells. The extracts possess either insulin-mimetic or insulin-sensitizing property or combination of both properties during enhancing glucose uptake into such cells. Meanwhile, the hot aqueous and methanolic extracts augmented basal and insulin-stimulated adiponectin secretion from adipocytes cells. From this study, it is suggested that Ficus deltoidea has the potential to be developed as future oral antidiabetic agent.
    MeSH terms: Complementary Therapies*; Diabetes Mellitus*; Plants, Medicinal; Ficus*
  2. Fulltext Management of chronic urticaria in Asia: 2010 AADV consensus guidelines
    Chow SK
    Asia Pac Allergy, 2012 Apr;2(2):149-60.
    PMID: 22701866 DOI: 10.5415/apallergy.2012.2.2.149
    This guideline is a result of a consensus reached during the 19th Asian-Australasian Regional Conference of Dermatology by the Asian Academy of Dermatology and Venereology Study Group in collaboration with the League of Asian Dermatological Societies in 2010. Urticaria has a profound impact on the quality of life in Asia and the need for effective treatment is required. In line with the EAACI/GA(2)LEN/EDF/WAO guideline for the management of urticaria the recommended first-line treatment is new generation, non-sedating H1-antihistamines. If standard dosing is ineffective, increasing the dosage up to four-fold is recommended. For patients who do not respond to a four-fold increase in dosage of non-sedating H1-antihistamines, it is recommended that therapies such as H2-antihistamine, leukotriene antagonist, and cyclosporine A should be added to the antihistamine treatment. In the choice of second-line treatment, both their costs and risk/benefit profiles are the most important considerations.
    MeSH terms: Asia; Dermatology; Histamine H1 Antagonists; Histamine H2 Antagonists; Humans; Quality of Life; Urticaria; Venereology; Cyclosporine; Anti-Allergic Agents; Leukotriene Antagonists; Consensus; Histamine H1 Antagonists, Non-Sedating
  3. Spatial-temporal variation of surface water quality in the downstream region of the Jakara River, north-western Nigeria: A statistical approach
    Mustapha A, Aris AZ, Ramli MF, Juahir H
    J Environ Sci Health A Tox Hazard Subst Environ Eng, 2012;47(11):1551-60.
    PMID: 22702815 DOI: 10.1080/10934529.2012.680415
    The pollution status of the downstream section of the Jakara River was investigated. Dissolved oxygen (DO), 5-day biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD), suspended solids (SS), pH, conductivity, salinity, temperature, nitrogen in the form of ammonia (NH(3)), turbidity, dissolved solids (DS), total solids (TS), nitrates (NO(3)), chloride (Cl) and phosphates (PO(3-)(4)) were evaluated, using both dry and wet season samples, as a measure of variation in surface water quality in the area. The results obtained from the analyses were correlated using Pearson's correlation matrix, principal component analysis (PCA) and paired sample t-tests. Positive correlations were observed for BOD(5), NH(3), COD, and SS, turbidity, conductivity, salinity, DS, TS for dry and wet seasons, respectively. PCA was used to investigate the origin of each water quality parameter, and yielded 5 varimax factors for each of dry and wet seasons, with 70.7 % and 83.1 % total variance, respectively. A paired sample t-test confirmed that the surface water quality varies significantly between dry and wet season samples (P < 0.01). The source of pollution in the area was concluded to be of anthropogenic origin in the dry season and natural origins in the wet season.
    MeSH terms: Environmental Monitoring; Nigeria; Seasons; Water Pollutants, Chemical/analysis*; Models, Statistical; Principal Component Analysis; Rivers/chemistry*; Water Quality/standards*
  4. Ventricular bigeminy following a cobra envenomation
    Ismail AK, Weinstein SA, Auliya M, Appareo P
    Clin Toxicol (Phila), 2012 Jul;50(6):518-21.
    PMID: 22702902 DOI: 10.3109/15563650.2012.696119
    Envenoming by some species of cobras (Naja species) may include cardiotoxic effects including various dysrhythmias. However, dysrhythmias leading specifically to ventricular bigeminy have not been previously documented. We report a case of cardiotoxicity and the development of ventricular bigeminy following a cobra envenomation.
    MeSH terms: Adult; Cobra Venoms/toxicity*; Electrocardiography; Humans; Male; Snake Bites/complications*; Ventricular Premature Complexes/etiology*
  5. Increasing glucose in KSOMaa basal medium on culture Day 2 improves in vitro development of cloned caprine blastocysts produced via intraspecies and interspecies somatic cell nuclear transfer
    Kwong PJ, Abdullah RB, Wan Khadijah WE
    Theriogenology, 2012 Sep 1;78(4):921-9.
    PMID: 22704387 DOI: 10.1016/j.theriogenology.2012.04.009
    This study was conducted to evaluate the efficiency of potassium simplex optimization medium with amino acids (KSOMaa) as a basal culture medium for caprine intraspecies somatic cell nuclear transfer (SCNT) and caprine-bovine interspecies somatic cell nuclear transfer (iSCNT) embryos. The effect of increased glucose as an energy substrate for late stage development of cloned caprine embryos in vitro was also evaluated. Enucleated caprine and bovine in vitro matured oocytes at metaphase II were reconstructed with caprine ear skin fibroblast cells for the SCNT and iSCNT studies. The cloned caprine and parthenogenetic embryos were cultured in either KSOMaa with 0.2 mM glucose for 8 days (Treatment 1) or KSOMaa for 2 days followed by KSOMaa with additional glucose at a final concentration of 2.78 mM for the last 6 days (Treatment 2). There were no significant differences in the cleavage rates of SCNT (80.7%) and iSCNT (78.0%) embryos cultured in KSOMaa medium. Both Treatment 1 and Treatment 2 could support in vitro development of SCNT and iSCNT embryos to the blastocyst stage. However, the blastocyst development rate of SCNT embryos was significantly higher (P < 0.05) in Treatment 2 compared to Treatment 1. Increasing glucose for later stage embryo development (8-cell stage onwards) during in vitro culture (IVC) in Treatment 2 also improved both caprine SCNT and iSCNT embryo development to the hatched blastocyst stage. In conclusion, this study shows that cloned caprine embryos derived from SCNT and iSCNT could develop to the blastocyst stage in KSOMaa medium supplemented with additional glucose (2.78 mM, final concentration) and this medium also supported hatching of caprine cloned blastocysts.
    MeSH terms: Amino Acids/pharmacology; Animals; Blastocyst/drug effects*; Blastocyst/physiology; Cattle; Culture Media/pharmacology*; Culture Media/chemistry; Dose-Response Relationship, Drug; Female; Glucose/pharmacology*; Hybrid Cells/cytology; Hybrid Cells/drug effects; Hybrid Cells/physiology; Hybridization, Genetic/drug effects; Hybridization, Genetic/physiology; Potassium/pharmacology; Species Specificity; Time Factors; Cloning, Organism/veterinary; Embryo Culture Techniques/methods*; Embryo Culture Techniques/veterinary; Embryonic Development/drug effects*; Embryonic Development/physiology
  6. Fulltext The nutritional impacts of soil-transmitted helminths infections among Orang Asli schoolchildren in rural Malaysia
    Ahmed A, Al-Mekhlafi HM, Al-Adhroey AH, Ithoi I, Abdulsalam AM, Surin J
    Parasit Vectors, 2012;5:119.
    PMID: 22704549 DOI: 10.1186/1756-3305-5-119
    Soil-transmitted helminths (STH) infections, anaemia and malnutrition are major public health problems in school-age children in developing countries. This study was conducted on 289 Orang Asli (aboriginal) schoolchildren in order to assess the current prevalence and predictors of anaemia and malnutrition, as well as the nutritional impacts of STH infections among these children.
    MeSH terms: Adolescent; Animals; Child; Cross-Sectional Studies; Female; Helminthiasis/complications; Helminthiasis/parasitology*; Humans; Malaysia/epidemiology; Male; Nutritional Status/physiology*; Soil/parasitology*
  7. Bioregeneration of mono-amine modified silica and granular activated carbon loaded with Acid Orange 7 in batch system
    Al-Amrani WA, Lim PE, Seng CE, Ngah WS
    Bioresour Technol, 2012 Aug;118:633-7.
    PMID: 22704829 DOI: 10.1016/j.biortech.2012.05.090
    The objectives of this study were: (1) to investigate the role of mixed culture of biomass in the regeneration of mono-amine modified silica (MAMS) and granular activated carbon (GAC) loaded with Acid Orange 7 (AO7), (2) to quantify and compare the bioregeneration efficiencies of AO7-loaded MAMS and GAC using the sequential adsorption and biodegradation approach and (3) to evaluate the reusability of bioregenerated MAMS. The results show that considerably higher bioregeneration efficiency of AO7-loaded MAMS as compared to that of AO7-loaded GAC was achieved due to higher reversibility of adsorption of MAMS for AO7 and favorable pH factor resulting in more AO7 desorption. The progressive loss of adsorption capacity of MAMS for AO7 with multiple cycles of use suggests possible chemical and microbial fouling of the adsorption sites.
    MeSH terms: Adsorption; Amines/chemistry*; Azo Compounds/chemistry*; Benzenesulfonates/chemistry*; Biodegradation, Environmental; Charcoal/chemistry*; Silicon Dioxide/chemistry*; Time Factors; Biological Oxygen Demand Analysis; Recycling/methods*; Batch Cell Culture Techniques/methods*
  8. Toxicological evaluation of 80% methanol extract of Ludwigia octovalvis (Jacq.) P.H. Raven leaves (Onagraceae) in BALB/c mice
    Kadum Yakob H, Manaf Uyub A, Fariza Sulaiman S
    J Ethnopharmacol, 2012 Aug 1;142(3):663-8.
    PMID: 22705121 DOI: 10.1016/j.jep.2012.05.035
    Ludwigia octovalvis (Jacq.) P. H. Raven (Family: Onagraceae), as a traditional Malay herbal medicine,has been used to treat gastrointestinal complaints such as diarrhea and dysentery.
    MeSH terms: Alanine Transaminase/blood; Methanol/chemistry; Alkaline Phosphatase/blood; Animals; Aspartate Aminotransferases/blood; Cholesterol/blood; Female; Leukocyte Count; Male; Mice, Inbred BALB C; Plant Extracts/toxicity*; Solvents/chemistry; Plant Leaves/chemistry; Onagraceae*; Mice
  9. Novel MDM2 splice variants identified from oral squamous cell carcinoma
    Sam KK, Gan CP, Yee PS, Chong CE, Lim KP, Karen-Ng LP, et al.
    Oral Oncol, 2012 Nov;48(11):1128-35.
    PMID: 22705356 DOI: 10.1016/j.oraloncology.2012.05.016
    The presence of a variety of MDM2 splice variants has been reported in a range of different tumor types and is associated with poor patient prognosis. Furthermore, several MDM2 variants have been shown to have oncogenic properties. Despite this, MDM2 splice variants have not been comprehensively characterized in oral squamous cell carcinoma (OSCC).
    MeSH terms: Carcinoma, Squamous Cell/genetics*; Cell Transformation, Neoplastic/genetics; Humans; Lymphatic Metastasis; Mouth Mucosa/physiology*; Mouth Neoplasms/genetics*; Mutation; RNA Splicing/genetics*; Polymerase Chain Reaction; Genes, p53/genetics; Proto-Oncogene Proteins c-mdm2/genetics*
  10. Ambient temperature detection of PCR amplicons with a novel sequence-specific nucleic acid lateral flow biosensor
    Ang GY, Yu CY, Yean CY
    Biosens Bioelectron, 2012 Oct-Dec;38(1):151-6.
    PMID: 22705404 DOI: 10.1016/j.bios.2012.05.019
    In the field of diagnostics, molecular amplification targeting unique genetic signature sequences has been widely used for rapid identification of infectious agents, which significantly aids physicians in determining the choice of treatment as well as providing important epidemiological data for surveillance and disease control assessment. We report the development of a rapid nucleic acid lateral flow biosensor (NALFB) in a dry-reagent strip format for the sequence-specific detection of single-stranded polymerase chain reaction (PCR) amplicons at ambient temperature (22-25°C). The NALFB was developed in combination with a linear-after-the-exponential PCR assay and the applicability of this biosensor was demonstrated through detection of the cholera toxin gene from diarrheal-causing toxigenic Vibrio cholerae. Amplification using the advanced asymmetric PCR boosts the production of fluorescein-labeled single-stranded amplicons, allowing capture probes immobilized on the NALFB to hybridize specifically with complementary targets in situ on the strip. Subsequent visual formation of red lines is achieved through the binding of conjugated gold nanoparticles to the fluorescein label of the captured amplicons. The visual detection limit observed with synthetic target DNA was 0.3 ng and 1 pg with pure genomic DNA. Evaluation of the NALFB with 164 strains of V. cholerae and non-V. cholerae bacteria recorded 100% for both sensitivity and specificity. The whole procedure of the low-cost NALFB, which is performed at ambient temperature, eliminates the need for preheated buffers or additional equipment, greatly simplifying the protocol for sequence-specific PCR amplicon analysis.
    MeSH terms: Base Sequence; Cholera/diagnosis; Cholera/microbiology*; Cholera Toxin/genetics*; DNA, Bacterial/analysis*; DNA, Bacterial/genetics; Gold/chemistry; Humans; Molecular Sequence Data; Reagent Strips/analysis; Sensitivity and Specificity; Temperature; Vibrio cholerae/genetics*; Vibrio cholerae/isolation & purification; Biosensing Techniques/economics; Biosensing Techniques/methods*; Polymerase Chain Reaction/economics; Polymerase Chain Reaction/methods*; Nanoparticles/chemistry; Limit of Detection
  11. Life-saving percutaneous intervention in young patient with massive pulmonary embolism
    Yaakob ZH, Undok AW, Abidin IZ, Wan Ahmad WA
    Ann Saudi Med, 2012 6 19;32(4):433-6.
    PMID: 22705620
    Massive pulmonary embolism (PE) is not an uncommon condition, and it usually carries a high risk of mortality. It is one of the fatal conditions that commonly affect young patients. A definitive treatment for patients with massive PE is still lacking, and surgical intervention carries a substantial mortality risk. Thus, percutaneous intervention (clot fragmentation and/or aspiration) remains an option in some patients, specifically in those with a risk of bleeding, contraindicating the use of thrombolysis. There have been no randomized trials to validate percutaneous intervention in massive PE. A sufficient level of evidence is still lacking, and its use depends upon the expert committee's opinion and study of previous case reports. We present a 23-year-old man with first onset massive PE secondary to protein C deficiency, who was treated successfully with the combination of systemic thrombolysis and percutaneous interventions.
    MeSH terms: Angiography; Catheterization/methods; Combined Modality Therapy; Humans; Male; Pulmonary Embolism/etiology; Pulmonary Embolism/physiopathology; Pulmonary Embolism/therapy*; Thrombolytic Therapy/methods*; Protein C Deficiency/complications*; Young Adult
  12. Characteristics of treated effluents and their potential applications for producing concrete
    Noruzman AH, Muhammad B, Ismail M, Abdul-Majid Z
    J Environ Manage, 2012 Nov 15;110:27-32.
    PMID: 22705857 DOI: 10.1016/j.jenvman.2012.05.019
    Conservation and preservation of freshwater is increasingly becoming important as the global population grows. Presently, enormous volumes of freshwater are used to mix concrete. This paper reports experimental findings regarding the feasibility of using treated effluents as alternatives to freshwater in mixing concrete. Samples were obtained from three effluent sources: heavy industry, a palm-oil mill and domestic sewage. The effluents were discharge into public drain without danger to human health and natural environment. Chemical compositions and physical properties of the treated effluents were investigated. Fifteen compositional properties of each effluent were correlated with the requirements set out by the relevant standards. Concrete mixes were prepared using the effluents and freshwater to establish a base for control performance. The concrete samples were evaluated with regard to setting time, workability, compressive strength and permeability. The results show that except for some slight excesses in total solids and pH, the properties of the effluents satisfy the recommended disposal requirements. Two concrete samples performed well for all of the properties investigated. In fact, one sample was comparatively better in compressive strength than the normal concrete; a 9.4% increase was observed at the end of the curing period. Indeed, in addition to environmental conservation, the use of treated effluents as alternatives to freshwater for mixing concrete could save a large amount of freshwater, especially in arid zones.
    MeSH terms: Conservation of Natural Resources; Construction Materials/analysis*; Fresh Water; Industrial Waste/analysis; Plant Oils/analysis; Sewage/analysis; Waste Disposal, Fluid/economics; Waste Disposal, Fluid/methods*; Water Pollution, Chemical/prevention & control; Waste Water/analysis*; Waste Water/chemistry*
  13. Development of a multiplex PCR assay for rapid identification of Burkholderia pseudomallei, Burkholderia thailandensis, Burkholderia mallei and Burkholderia cepacia complex
    Koh SF, Tay ST, Sermswan R, Wongratanacheewin S, Chua KH, Puthucheary SD
    J Microbiol Methods, 2012 Sep;90(3):305-8.
    PMID: 22705921 DOI: 10.1016/j.mimet.2012.06.002
    We have developed a multiplex PCR assay for rapid identification and differentiation of cultures for Burkholderia pseudomallei, Burkholderia thailandensis, Burkholderia mallei and Burkholderia cepacia complex. The assay is valuable for use in clinical and veterinary laboratories, and in a deployable laboratory during outbreaks.
    MeSH terms: Electrophoresis, Agar Gel; Genes, Bacterial; RNA, Bacterial/genetics; RNA, Ribosomal, 16S/genetics; Burkholderia pseudomallei/genetics*; Burkholderia cepacia complex/genetics*; Burkholderia mallei/genetics*; Molecular Typing; Multiplex Polymerase Chain Reaction*
  14. Fulltext NIR spectroscopic properties of aqueous acids solutions
    Omar AF, Atan H, Matjafri MZ
    Molecules, 2012 Jun 15;17(6):7440-50.
    PMID: 22706373 DOI: 10.3390/molecules17067440
    Acid content is one of the important quality attributes in determining the maturity index of agricultural product, particularly fruits. Despite the fact that much research on the measurement of acidity in fruits through non-destructive spectroscopy analysis at NIR wavelengths between 700 to 1,000 nm has been conducted, the same response towards individual acids is not well known. This paper presents NIR spectroscopy analysis on aqueous citric, tartaric, malic and oxalic solutions through quantitative analysis by selecting a set of wavelengths that can best be used to measure the pH of the solutions. The aquaphotomics study of the acid solutions has generated R² above 0.9 for the measurement of all acids. The most important wavelengths for pH are located at 918-925 nm and 990-996 nm, while at 975 nm for water.
    MeSH terms: Acids/chemistry*; Fruit/chemistry; Hydrogen-Ion Concentration; Malates/chemistry; Oxalates/chemistry; Solutions; Tartrates/chemistry; Spectroscopy, Near-Infrared*; Citric Acid/chemistry
  15. WHO guidelines for treatment of tuberculosis: the missing links
    Atif M, Sulaiman SA, Shafie AA, Ali I, Hassali MA, Saleem F
    Int J Clin Pharm, 2012 Aug;34(4):506-9.
    PMID: 22706597 DOI: 10.1007/s11096-012-9657-8
    Worldwide, the treatment of tuberculosis is based on evidence-based guidelines developed by the World Health Organization (WHO) for national tuberculosis programs. However, the importance of health related quality of life, the adequate management of side effects associated with antituberculosis drugs and the elaboration of tuberculosis treatment outcome categories are a few issues that need to be addressed in forthcoming WHO guidelines for the treatment of tuberculosis.
    MeSH terms: Antitubercular Agents/adverse effects*; Antitubercular Agents/therapeutic use; Exanthema/chemically induced; Exanthema/drug therapy*; Histamine Antagonists/therapeutic use; Humans; Pruritus/chemically induced; Pruritus/drug therapy*; Quality of Life/psychology; Tuberculosis/drug therapy*; Tuberculosis/psychology*; World Health Organization*; Treatment Outcome; Guidelines as Topic
  16. Fulltext Psychosocial impact of perinatal loss among Muslim women
    Sutan R, Miskam HM
    BMC Womens Health, 2012;12:15.
    PMID: 22708998 DOI: 10.1186/1472-6874-12-15
    Women of reproductive age are vulnerable to psychosocial problems, but these have remained largely unexplored in Muslim women in developing countries. The aim of this study was to explore and describe psychosocial impact and social support following perinatal loss among Muslim women.
    MeSH terms: Anger; Anxiety; Bereavement*; Confusion; Death*; Decision Making; Female; Guilt; Humans; Infant, Newborn; Islam/psychology*; Malaysia; Mothers/psychology*; Pregnancy; Professional-Patient Relations; Social Support; Focus Groups; Spouses; Qualitative Research; Stillbirth/psychology*
  17. Fulltext Knockdown of PLC-gamma-2 and calmodulin 1 genes sensitizes human cervical adenocarcinoma cells to doxorubicin and paclitaxel
    Stanislaus A, Bakhtiar A, Salleh D, Tiash S, Fatemian T, Hossain S, et al.
    Cancer Cell Int, 2012 Jun 18;12(1):30.
    PMID: 22709569 DOI: 10.1186/1475-2867-12-30
    BACKGROUND: RNA interference (RNAi) is a powerful approach in functional genomics to selectively silence messenger mRNA (mRNA) expression and can be employed to rapidly develop potential novel drugs against a complex disease like cancer. However, naked siRNA being anionic is unable to cross the anionic cell membrane through passive diffusion and therefore, delivery of siRNA remains a major hurdle to overcome before the potential of siRNA technology can fully be exploited in cancer. pH-sensitive carbonate apatite has recently been developed as an efficient tool to deliver siRNA into the mammalian cells by virtue of its high affinity interaction with the siRNA and the desirable size distribution of the resulting siRNA-apatite complex for effective cellular endocytosis. Moreover, internalized siRNA was found to escape from the endosomes in a time-dependent manner and efficiently silence gene expression.

    RESULTS: Here we show that carbonate apatite-mediated delivery of siRNA against PLC-gamma-2 (PLCG2) and calmodulin 1 (CALM1) genes has led to the sensitization of a human cervical cancer cell line to doxorubicin- and paclitaxel depending on the dosage of the individual drug whereas no such enhancement in cell death was observed with cisplatin irrespective of the dosage following intracellular delivery of the siRNAs.

    CONCLUSION: Thus, PLCG2 and CALM1 genes are two potential targets for gene knockdown in doxorubicin and paclitaxel-based chemotherapy of cervical cancer.

  18. Fulltext Outbreak-associated Vibrio cholerae genotypes with identical pulsotypes, Malaysia, 2009
    Teh CS, Suhaili Z, Lim KT, Khamaruddin MA, Yahya F, Sajili MH, et al.
    Emerg Infect Dis, 2012 Jul;18(7):1177-9.
    PMID: 22709679 DOI: 10.3201/eid1807.111656
    A cholera outbreak in Terengganu, Malaysia, in November 2009 was caused by 2 El Tor Vibrio cholerae variants resistant to typical antimicrobial drugs. Evidence of replacement of treatable V. cholerae infection in the region with antimicrobial-resistant strains calls for increased surveillance and prevention measures.
    MeSH terms: Amino Acid Sequence; Anti-Bacterial Agents/pharmacology; Cholera/microbiology; Cholera/epidemiology*; Cholera Toxin/genetics*; Cholera Toxin/metabolism; Cholera Toxin/chemistry; Disease Outbreaks*; DNA, Bacterial/genetics; Environment; Genotype; Humans; Malaysia/epidemiology; Microbial Sensitivity Tests; Molecular Sequence Data; Vibrio cholerae/classification*; Vibrio cholerae/drug effects; Vibrio cholerae/genetics*; Vibrio cholerae/isolation & purification; Bacterial Typing Techniques; Polymerase Chain Reaction; Sequence Alignment; Sequence Analysis, DNA; Drug Resistance, Bacterial; Vibrio cholerae O1/classification*; Vibrio cholerae O1/drug effects; Vibrio cholerae O1/genetics*; Vibrio cholerae O1/isolation & purification
  19. Fulltext Design, synthesis and antiviral potential of 14-aryl/heteroaryl-14H-dibenzo[a,j]xanthenes using an efficient polymer-supported catalyst
    Reddi Mohan Naidu K, Satheesh Krishna B, Anil Kumar M, Arulselvan P, Ibrahim Khalivulla S, Lasekan O
    Molecules, 2012 Jun 18;17(6):7543-55.
    PMID: 22710828 DOI: 10.3390/molecules17067543
    Polyethyleneglycol bound sulfonic acid (PEG-OSO₃H), a chlorosulphonic acid-modified polyethylene glycol was successfully used as an efficient and eco-friendly polymeric catalyst in the synthesis of 14-aryl/heteroaryl-14H-dibenzo[a,j]xanthenes obtained from the reaction of 2-naphthol and carbonyl compounds under solvent-free conditions with short reaction times and excellent yields. The biological properties of these synthesized title compounds revealed that compounds 3b, 3c, 3f and 3i showed highly significant anti-viral activity against tobacco mosaic virus.
    MeSH terms: Aldehydes/chemistry; Antiviral Agents/chemical synthesis*; Antiviral Agents/pharmacology*; Antiviral Agents/chemistry; Catalysis; Naphthols/chemistry; Polyethylene Glycols/chemistry; Polymers/chemistry*; Temperature; Tobacco Mosaic Virus/drug effects; Xanthenes/chemical synthesis*; Xanthenes/pharmacology*; Xanthenes/chemistry
  20. Structural prediction of a novel chitinase from the psychrophilic Glaciozyma antarctica PI12 and an analysis of its structural properties and function
    Ramli AN, Mahadi NM, Shamsir MS, Rabu A, Joyce-Tan KH, Murad AM, et al.
    J Comput Aided Mol Des, 2012 Aug;26(8):947-61.
    PMID: 22710891 DOI: 10.1007/s10822-012-9585-7
    The structure of psychrophilic chitinase (CHI II) from Glaciozyma antarctica PI12 has yet to be studied in detail. Due to its low sequence identity (<30 %), the structural prediction of CHI II is a challenge. A 3D model of CHI II was built by first using a threading approach to search for a suitable template and to generate an optimum target-template alignment, followed by model building using MODELLER9v7. Analysis of the catalytic insertion domain structure in CHI II revealed an increase in the number of aromatic residues and longer loops compared to mesophilic and thermophilic chitinases. A molecular dynamics simulation was used to examine the stability of the CHI II structure at 273, 288 and 300 K. Structural analysis of the substrate-binding cleft revealed a few exposed aromatic residues. Substitutions of certain amino acids in the surface and loop regions of CHI II conferred an increased flexibility to the enzyme, allowing for an adaptation to cold temperatures. A substrate binding comparison of CHI II with the mesophilic chitinase from Coccidioides immitis, 1D2K, suggested that the psychrophilic adaptation and catalytic activity at low temperatures were achieved through a reduction in the number of salt bridges, fewer hydrogen bonds and an increase in the exposure of the hydrophobic side chains to the solvent.
    MeSH terms: Adaptation, Physiological*; Amino Acid Sequence; Basidiomycota/enzymology*; Chitinase/chemistry*; Cold Temperature; Hydrogen Bonding; Molecular Conformation; Molecular Sequence Data; Catalytic Domain; Molecular Dynamics Simulation*
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