Displaying publications 81 - 100 of 201 in total

Abstract:
Sort:
  1. Discovery of novel methanone derivatives acting as antimycobacterial agents
    Ali MA, Bastian S, Ismail R, Choon TS, Ali S, Aubry A, et al.
    J Enzyme Inhib Med Chem, 2011 Dec;26(6):890-4.
    PMID: 21395486 DOI: 10.3109/14756366.2011.559945
    A series of pyrazoline derivatives were synthesized and in vitro activity against Mycobacterium tuberculosis H37Rv was carried out. Among the synthesized compounds, compounds (4d) and (4f) 4-aminophenyl-3-(3,4-dimethoxyphenyl)-6,7-dimethoxy-2,3,3a,4-tetrahydroindeno[1,2-c]pyrazol-2-ylmethanone and 4-aminophenyl-6,7-dimethoxy-3-phenyl-2,3,3a,4-tetrahydroindeno[1,2-c]pyrazol-2-ylmethanone were found to be the most active agent against M. tuberculosis H37Rv with a minimum inhibitory concentration of 10 μg/mL.
    Matched MeSH terms: Mycobacterium tuberculosis/drug effects*
  2. Diagnostic challenge of gastrointestinal tuberculosis: a report of 34 cases and an overview of the literature
    Radzi M, Rihan N, Vijayalakshmi N, Pani SP
    Southeast Asian J. Trop. Med. Public Health, 2009 May;40(3):505-10.
    PMID: 19842436
    We report 34 cases of gastrointestinal TB from Malaysia and present an overview of the diagnostic challenges. A concerted effort is necessary to improve the existing diagnostic methods, and develop and evaluate newer diagnostic tools through well designed multi-center studies.
    Matched MeSH terms: Mycobacterium tuberculosis/isolation & purification*
  3. Antioxidant, anti-TB activities, phenolic and amide contents of standardised extracts of Piper sarmentosum Roxb
    Hussain K, Ismail Z, Sadikun A, Ibrahim P
    Nat Prod Res, 2009;23(3):238-49.
    PMID: 19235024 DOI: 10.1080/14786410801987597
    Ethanol and aqueous extracts of the different parts of Piper sarmentosum were analysed by HPLC for marker compounds to standardise these extracts. The standardised extracts were investigated for antioxidant activity (beta-carotene linoleate model and DPPH model), anti-TB activity (microplate tetrazolium assay), and estimation of total phenolic and amide contents. The extracts of the different parts exhibited different antioxidant activity, phenolic and amide contents (p < 0.01). The ethanol extracts exhibited better antioxidant activity as compared to the aqueous extracts. The leaf ethanol extract was further investigated for dose response relationship and its EC(50) was found to be 38 microg mL(-1). All the extracts have exhibited anti-TB activity with MIC/MBC 12.5 microg mL(-1). The leaf methanol extract was fractionated and the ethyl acetate fraction exhibited anti-TB activity with MIC/MBC 3.12 microg mL(-1) while MIC/MBC of isoniazid (INH) was found to be 0.5 microg mL(-1). A positive correlation was found between antioxidant activity and total polyphenols, flavonoids and amides, in the beta-carotene linoleate model (p = 0.05) and in the DPPH model (p = 0.01). The analytical method was found to have linearity >0.9922, coefficient of variance <5% and accuracy 95.5 +/- 5 to 96.9 +/- 5. This plant possesses promising antioxidant as well as anti-TB properties.
    Matched MeSH terms: Mycobacterium tuberculosis/drug effects*
  4. Meta-analysis: the association between HIV infection and extrapulmonary tuberculosis
    Naing C, Mak JW, Maung M, Wong SF, Kassim AI
    Lung, 2013 Feb;191(1):27-34.
    PMID: 23180033 DOI: 10.1007/s00408-012-9440-6
    BACKGROUND: Extrapulmonary tuberculosis has been an AIDS-defining condition. Individual studies that highlight the association between HIV and extrapulmonary TB are available. Our objectives were to synthesis evidence on the association between extrapulmonary tuberculosis and HIV and to explore the effective preventive measures of these two diseases.

    METHODS: This is a meta-analysis of observational studies reporting effect estimates on how HIV is associated with extrapulmonary tuberculosis. We searched for the eligible studies in the electronic databases using search terms related to HIV and extrapulmonary tuberculosis. Where possible, we estimated the summary odds ratios using random effects meta-analysis. We stratified analysis by the type of study design. We assessed heterogeneity of effect estimates within each group of studies was assessed using I (2) test.

    RESULTS: Nineteen studies (7 case control studies and 12 cohort studies) were identified for the present study. The pooled analysis shows a significant association between HIV and extrapulmonary tuberculosis (summary odds ratio: 1.3; 95 % confidence interval (CI) 1.05-1.6; I (2): 0 %). In a subgroup analysis with two studies, a significant association was found between CD4+ count less than 100 and the incidence of extrapulmonary tuberculosis (summary OR: 1.31; 95 % CI 1.02-1.68; I (2): 0 %).

    CONCLUSIONS: Findings show evidence on the association between extrapulmonary tuberculosis and HIV, based on case control studies. Further studies to understand the mechanisms of interaction of the two pathogens are recommended.

    Matched MeSH terms: Mycobacterium tuberculosis/physiology
  5. Structural insights on Mycobacterium tuberculosis thiazole synthase--a molecular dynamics/docking approach
    Rohini K, Srikumar PS
    Appl Biochem Biotechnol, 2013 Mar;169(6):1790-8.
    PMID: 23340867 DOI: 10.1007/s12010-013-0110-9
    Tuberculosis (TB), an epidemic disease, affects the world with death rate of two million people every year. The bacterium Mycobacterium tuberculosis was found to be a more potent and disease-prolonged bacterium among the world due to multi-drug resistance. Emergence of new drug targets is needed to overcome the bacterial resistance that leads to control epidemic tuberculosis. The pathway thiamine biosynthesis was targeting M. tuberculosis due to its role in intracellular growth of the bacterium. The screening of enzymes involved in thiamin biosynthesis showed novel target thiazole synthase (ThiG) involved in catalysis of rearrangement of 1-deoxy-D-xylulose 5-phosphate (DXP) to produce the thiazole phosphate moiety of thiamine. We carried out homology modeling for ThiG to understand the structure-function relationship, and the model was refined with MD simulations. The results showed that the model predicted with (α + β)8-fold of synthase family proteins. Molecular docking of ThiG model with substrate DXP showed binding mode and key residues ARG46, ASN69, THR41, and LYS96 involved in the catalysis. First-line anti-tuberculosis drugs were docked with ThiG to identify the inhibition. The report showed the anti-tuberculosis drugs interact well with ThiG which may lead to block thiamin biosynthesis pathway.
    Matched MeSH terms: Mycobacterium tuberculosis/enzymology*
  6. Current prospects of synthetic curcumin analogs and chalcone derivatives against mycobacterium tuberculosis
    Bukhari SN, Franzblau SG, Jantan I, Jasamai M
    Med Chem, 2013 Nov;9(7):897-903.
    PMID: 23305394
    Tuberculosis, caused by Mycobacterium tuberculosis, is amongst the foremost infectious diseases. Treatment of tuberculosis is a complex process due to various factors including a patient's inability to persevere with a combined treatment regimen, the difficulty in eradicating the infection in immune-suppressed patients, and multidrug resistance (MDR). Extensive research circumscribing molecules to counteract this disease has led to the identification of many inhibitory small molecules. Among these are chalcone derivatives along with curcumin analogs. In this review article, we summarize the reported literature regarding anti tubercular activity of chalcone derivatives and synthetic curcumin analogs. Our goal is to provide an analysis of research to date in order to facilitate the synthesis of superior antitubercular chalcone derivatives and curcumin analogs.
    Matched MeSH terms: Mycobacterium tuberculosis/drug effects*
  7. Fulltext Psychosis secondary to tuberculosis meningitis
    Rahim MJ, Ghazali WS
    BMJ Case Rep, 2016 Mar 11;2016.
    PMID: 26969352 DOI: 10.1136/bcr-2015-213171
    We report a case of a 19-year-old immunocompetent Malay woman who presented with a worsening psychotic disorder of 1-year duration. She initially presented with social isolation with subsequent mutism and stupor. Physical examination revealed a stuporous, emaciated, dehydrated woman with Glasgow Coma Scale of 11/15 (E4V2M5). She had a blank stare, mutism and akinesia. Motor examination revealed upper motor neuron findings. Neck stiffness was present, however, Kernig's and Brudzinski's signs were negative. There were no other findings on other systems. Brain imaging and EEG were normal. Cerebrospinal fluid investigations revealed positive cerebrospinal fluid Mycobacterium tuberculosis PCR (MTB PCR). The patient was treated with empirical antituberculosis drugs and steroids. On follow-up visit 1 month later, her psychotic symptoms had fully resolved. She was able to ambulate and care for herself; she was unable to recall the symptoms she had experienced before and during admission.
    Matched MeSH terms: Mycobacterium tuberculosis/isolation & purification
  8. Fulltext Vaccines for TB: Lessons from the Past Translating into Future Potentials
    Tye GJ, Lew MH, Choong YS, Lim TS, Sarmiento ME, Acosta A, et al.
    J Immunol Res, 2015;2015:916780.
    PMID: 26146643 DOI: 10.1155/2015/916780
    Development of vaccines for infectious diseases has come a long way with recent advancements in adjuvant developments and discovery of new antigens that are capable of eliciting strong immunological responses for sterile eradication of disease. Tuberculosis (TB) that kills nearly 2 million of the population every year is also one of the highlights of the recent developments. The availability or not of diagnostic methods for infection has implications for the control of the disease by the health systems but is not related to the immune surveillance, a phenomenon derived from the interaction between the bacteria and their host. Here, we will review the immunology of TB and current vaccine candidates for TB. Current strategies of developing new vaccines against TB will also be reviewed in order to further discuss new insights into immunotherapeutic approaches involving adjuvant and antigens combinations that might be of potential for the control of TB.
    Matched MeSH terms: Mycobacterium tuberculosis/immunology*
  9. A prospective study of mycobacterial viability in refrigerated, unpreserved sputum batched for up to 8 weeks
    Rashid Ali MR, Parameswaran U, William T, Bird E, Wilkes CS, Lee WK, et al.
    Int J Tuberc Lung Dis, 2015 May;19(5):620-1.
    PMID: 25868033 DOI: 10.5588/ijtld.14.0938
    Matched MeSH terms: Mycobacterium tuberculosis/isolation & purification*
  10. Fulltext Drug resistant Mycobacterium tuberculosis
    Lim VK
    Med J Malaysia, 1993 Jun;48(2):97-8.
    PMID: 8350810
    Matched MeSH terms: Mycobacterium tuberculosis/drug effects*
  11. Insertion sequence typing of Mycobacterium tuberculosis: characterization of a widespread subtype with a single copy of IS6110
    Fomukong NG, Tang TH, al-Maamary S, Ibrahim WA, Ramayah S, Yates M, et al.
    Tuber. Lung Dis., 1994 Dec;75(6):435-40.
    PMID: 7718832 DOI: 10.1016/0962-8479(94)90117-1
    DNA fingerprinting with the insertion sequence IS6110 (also known as IS986) has become established as a major tool for investigating the spread of tuberculosis. Most strains of Mycobacterium tuberculosis have multiple copies of IS6110, but a small minority carry a single copy only. We have examined selected strains from Malaysia, Tanzania and Oman, in comparison with M. bovis isolates and BCG strains carrying one or two copies of IS6110. The insertion sequence appears to be present in the same position in all these strains, which suggests that in these organisms the element is defective in transposition and that the loss of transposability may have occurred at an early stage in the evolution of the M. tuberculosis complex.
    Matched MeSH terms: Mycobacterium tuberculosis/genetics*
  12. Fulltext Protean manifestations of gastrointestinal tuberculosis
    Ismail Y, Muhamad A
    Med J Malaysia, 2003 Aug;58(3):345-9.
    PMID: 14750373
    We present 11 cases to illustrate the protean presentations of gastrointestinal tuberculosis. The patients presented with perianal fistula, appendicitis, ascites, rectal, intestinal or gastric 'growth', "ulcerative colitis", or recurrent anemia. In some of these cases there was no conclusive proof of infection with Mycobacterium tuberculosis but they responded well to empirical treatment with anti-tuberculous therapy. These cases illustrate that because signs and symptoms of intestinal tuberculosis are non-specific and even histology can be misleading, the diagnosis of gastrointestinal tuberculosis requires a high index of suspicion. A therapeutic trial of antituberculous drugs should be considered for patients with a high clinical suspicion of tuberculosis.
    Matched MeSH terms: Mycobacterium tuberculosis/physiology
  13. Fulltext Computational, crystallographic studies, cytotoxicity and anti-tubercular activity of substituted 7-methoxy-indolizine analogues
    Venugopala KN, Chandrashekharappa S, Pillay M, Abdallah HH, Mahomoodally FM, Bhandary S, et al.
    PLoS One, 2019;14(6):e0217270.
    PMID: 31163040 DOI: 10.1371/journal.pone.0217270
    Indolizines are heteroaromatic compounds, and their synthetic analogues have reportedly showed promising pharmacological properties. In this study, a series of synthetic 7-methoxy-indolizine derivatives were synthesised, characterised and evaluated for in vitro whole-cell anti-tuberculosis (TB) screening against susceptible (H37Rv) and multi-drug-resistant (MDR) strains of Mycobacterium tuberculosis (MTB) using the resazurin microplate assay method. The cytotoxicity was evaluated using the MTT assay. In silico molecular-docking study was conducted for compounds 5a-j against enoyl-[acyl-carrier] protein reductase, a key enzyme of the type II fatty acid synthesis that has attracted much interest for the development of novel anti-TB compounds. Thereafter, molecular dynamic (MD) simulation was undertaken for the most active inhibitors. Compounds 5i and 5j with the methoxy functional group at the meta position of the benzoyl group, which was at the third position of the indolizine nucleus, demonstrated encouraging anti-TB activity against MDR strains of MTB at 16 μg/mL. In silico studies showed binding affinity within the range of 7.07-8.57 kcal/mol, with 5i showing the highest binding affinity. Hydrogen bonding, π-π- interactions, and electrostatic interactions were common with the active site. Most of these interactions occurred with the catalytic amino acids (Pro193, Tyr158, Phe149, and Lys165). MD simulation showed that 5j possessed the highest binding affinity toward the enzyme, according to the two calculation methods (MM/PBSA and MM/GBSA). The single-crystal X-ray studies of compounds 5c and 5d revealed that the molecular arrangements in these two structures were mostly guided by C-H···O hydrogen-bonded dimeric motifs and C-H···N hydrogen bonds, while various secondary interactions (such as π···π and C-H···F) also contributed to crystal formation. Compounds 5a, 5c, 5i, and 5j exhibited no toxicity up to 500 μg/mL. In conclusion, 5i and 5j are promising anti-TB compounds that have shown high affinity based on docking and MD simulation results.
    Matched MeSH terms: Mycobacterium tuberculosis/growth & development*
  14. Fulltext Demystifying the catalytic pathway of Mycobacterium tuberculosis isocitrate lyase
    Ibeji CU, Salleh NAM, Sum JS, Ch'ng ACW, Lim TS, Choong YS
    Sci Rep, 2020 11 03;10(1):18925.
    PMID: 33144641 DOI: 10.1038/s41598-020-75799-8
    Pulmonary tuberculosis, caused by Mycobacterium tuberculosis, is one of the most persistent diseases leading to death in humans. As one of the key targets during the latent/dormant stage of M. tuberculosis, isocitrate lyase (ICL) has been a subject of interest for new tuberculosis therapeutics. In this work, the cleavage of the isocitrate by M. tuberculosis ICL was studied using quantum mechanics/molecular mechanics method at M06-2X/6-31+G(d,p): AMBER level of theory. The electronic embedding approach was applied to provide a better depiction of electrostatic interactions between MM and QM regions. Two possible pathways (pathway I that involves Asp108 and pathway II that involves Glu182) that could lead to the metabolism of isocitrate was studied in this study. The results suggested that the core residues involved in isocitrate catalytic cleavage mechanism are Asp108, Cys191 and Arg228. A water molecule bonded to Mg2+ acts as the catalytic base for the deprotonation of isocitrate C(2)-OH group, while Cys191 acts as the catalytic acid. Our observation suggests that the shuttle proton from isocitrate hydroxyl group C(2) atom is favourably transferred to Asp108 instead of Glu182 with a lower activation energy of 6.2 kcal/mol. Natural bond analysis also demonstrated that pathway I involving the transfer of proton to Asp108 has a higher intermolecular interaction and charge transfer that were associated with higher stabilization energy. The QM/MM transition state stepwise catalytic mechanism of ICL agrees with the in vitro enzymatic assay whereby Asp108Ala and Cys191Ser ICL mutants lost their isocitrate cleavage activities.
    Matched MeSH terms: Mycobacterium tuberculosis/enzymology*
  15. Applications of Ensemble Docking in Potential Inhibitor Screening for Mycobacterium tuberculosis Isocitrate Lyase Using a Local Plant Database
    Lee YV, Choi SB, Wahab HA, Lim TS, Choong YS
    J Chem Inf Model, 2019 05 28;59(5):2487-2495.
    PMID: 30840452 DOI: 10.1021/acs.jcim.8b00963
    Isocitrate lyase (ICL) is a persistent factor for the survival of dormant stage Mycobacterium tuberculosis (MTB), thus a potential drug target for tuberculosis treatment. In this work, ensemble docking approach was used to screen for potential inhibitors of ICL. The ensemble conformations of ICL active site were obtained from molecular dynamics simulation on three dimer form systems, namely the apo ICL, ICL in complex with metabolites (glyoxylate and succinate), and ICL in complex with substrate (isocitrate). Together with the ensemble conformations and the X-ray crystal structures, 22 structures were used for the screening against Malaysian Natural Compound Database (NADI). The top 10 compounds for each ensemble conformation were selected. The number of compounds was then further narrowed down to 22 compounds that were within the Lipinski's Rule of Five for drug-likeliness and were also docked into more than one ensemble conformation. Theses 22 compounds were furthered evaluate using whole cell assay. Some compounds were not commercially available; therefore, plant crude extracts were used for the whole cell assay. Compared to itaconate (the known inhibitor of ICL), crude extracts from Manilkara zapota, Morinda citrifolia, Vitex negundo, and Momordica charantia showed some inhibition activity. The MIC/MBC value were 12.5/25, 12.5/25, 0.78/1.6, and 0.39/1.6 mg/mL, respectively. This work could serve as a preliminary study in order to narrow the scope for high throughput screening in the future.
    Matched MeSH terms: Mycobacterium tuberculosis/enzymology*
  16. Antimycobacterial evaluation of novel hybrid arylidene thiazolidine-2,4-diones
    Ponnuchamy S, Kanchithalaivan S, Ranjith Kumar R, Ali MA, Choon TS
    Bioorg Med Chem Lett, 2014 Feb 15;24(4):1089-93.
    PMID: 24472146 DOI: 10.1016/j.bmcl.2014.01.007
    A series of novel hybrid heterocycles comprising arylidene thiazolidine-2,4-dione and 1-cyclopropyl-2-(2-fluorophenyl)ethanone were synthesized. These compounds were evaluated for their antimycobacterial activity against Mycobacterium tuberculosis H37Rv in High Throughput Screen. Most of the hybrid arylidene thiazolidine-2,4-diones displayed moderate to good activity with MIC of less than 50 μM. Compound 1m exhibited maximum potency being 5.87 fold more active at EC50 and 6.26 fold more active at EC90 than the standard drug pyrimethamine.
    Matched MeSH terms: Mycobacterium tuberculosis/drug effects*
  17. Interactions of domain antibody (dAbκ11) with Mycobacterium tuberculosis Ac2SGL in complex with CD1b
    Law CT, Camacho F, Garcia-Alles LF, Gilleron M, Sarmiento ME, Norazmi MN, et al.
    Tuberculosis (Edinb), 2019 01;114:9-16.
    PMID: 30711162 DOI: 10.1016/j.tube.2018.11.002
    Tuberculosis (TB) is the main cause of mortality among all infectious diseases. The presentation of lipids by CD1b molecules and the interactions of the CD1b-lipid complexes with the immune receptors are important for the understanding of the immune response to Mycobacterium tuberculosis (Mtb), and to develop TB control methods. A specific domain antibody (dAbk11) recognizing the complex of CD1b with Mtb sulphoglycolipid (Ac2SGL) had been previously developed. In order to study the interactions of dAbk11 with Ac2SGL:CD1b, the conformation of Ac2SGL within CD1b was first modelled. The orientation of dAbκ11 with Ac2SGL:CD1b was then predicted by a docking experiment and the complex was sampled using molecular dynamics simulation. Data showed that dAbκ11 Tyr32 OH plays a decisive role in interacting with Ac2SGL alkyl tail HO17. The binding free energy calculation showed that Ac2SGL establish strong hydrophobic interactions with dAbκ11. The model also predicted a higher affinity for the natural sulfoglycolipid (Ac2SGL) than the synthetic analogue (SGL12), which was supported by the ELISA data. These results shed light on the likely mechanism of interactions between Ac2SGL:CD1b and dAbκ11, thus making possible to envision the strategies for dAbκ11 optimization for possible future applications.
    Matched MeSH terms: Mycobacterium tuberculosis/immunology
  18. Fulltext Phenolic Compounds as Promising Drug Candidates in Tuberculosis Therapy
    Mazlun MH, Sabran SF, Mohamed M, Abu Bakar MF, Abdullah Z
    Molecules, 2019 Jul 04;24(13).
    PMID: 31277371 DOI: 10.3390/molecules24132449
    Tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB) remains one of the deadliest, infectious diseases worldwide. The detrimental effects caused by the existing anti-TB drugs to TB patients and the emergence of resistance strains of M. tuberculosis has driven efforts from natural products researchers around the globe in discovering novel anti-TB drugs that are more efficacious and with less side effects. There were eleven main review publications that focused on natural products with anti-TB potentials. However, none of them specifically emphasized antimycobacterial phenolic compounds. Thus, the current review's main objective is to highlight and summarize phenolic compounds found active against mycobacteria from 2000 to 2017. Based on the past studies in the electronic databases, the present review also focuses on several test organisms used in TB researches and their different distinct properties, a few types of in vitro TB bioassay and comparison between their strengths and drawbacks, different methods of extraction, fractionation and isolation, ways of characterizing and identifying isolated compounds and the mechanism of actions of anti-TB phenolic compounds as reported in the literature.
    Matched MeSH terms: Mycobacterium tuberculosis/drug effects
  19. A case of pulmonary tuberculosis masquerading as lung carcinoma
    Tan KT, Kannan SK, Rajahram GS
    Med J Malaysia, 2019 12;74(6):547-548.
    PMID: 31929486
    Tuberculosis is a nimble chameleon. It can manifest itself in various ways with atypical clinical and radiographic findings. In this report we discuss the importance of radiographic findings (nodular or mass-like forms) requiring a correlation with microbiological and histopathological results to differentiate lung cancer from TB.
    Matched MeSH terms: Mycobacterium tuberculosis/isolation & purification*
  20. Fulltext Detection of Mycobacterium tuberculosis complex antibodies in free-ranged wild boar and wild macaques in selected districts in Selangor and reevaluation of tuberculosis serodetection in captive Asian elephants in Pahang, Peninsular Malaysia
    Lekko YM, Che-Amat A, Ooi PT, Omar S, Mohd-Hamdan DT, Linazah LS, et al.
    J Vet Med Sci, 2021 Oct 31;83(11):1702-1707.
    PMID: 34544936 DOI: 10.1292/jvms.21-0144
    Tuberculosis (TB) is a chronic inflammatory and zoonotic disease caused by Mycobacterium tuberculosis complex (MTBC) members, affecting several domestic animals, wildlife species and humans. The preliminary investigation was aimed to detect antibody against MTBC among indigenous wildlife which are free-ranged wild boar, free-ranged wild macaques and captive Asian elephants in selected areas of Selangor and elephant conservation centre in Pahang, respectively. The results indicate that MTBC serodetection rate in wild boar was 16.7% (7.3-33.5 at 95% confidence interval (CI)) using an in-house ELISA bPPD IgG and 10% (3.5-25.6 at 95% CI) by DPP®VetTB assay, while the wild macaques and Asian elephant were seronegative. The univariate analysis indicates no statistically significant difference in risk factors for sex and age of wild boar but there was a significant positive correlation (P<0.05) between bovine TB in dairy cattle and wild boar seropositivity in the Sepang district.
    Matched MeSH terms: Mycobacterium tuberculosis*
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links