Displaying publications 121 - 140 of 198 in total

Abstract:
Sort:
  1. Ahmad L, Hung TL, Mat Akhir NA, Mohamed R, Nathan S, Firdaus-Raih M
    BMC Microbiol, 2015;15:270.
    PMID: 26597807 DOI: 10.1186/s12866-015-0604-4
    There are still numerous protein subfamilies within families and superfamilies that do not yet have conclusive empirical experimental evidence providing a specific function. These proteins persist in databases with the annotation of a specific 'putative' function made by association with discernible features in the protein sequence.
    Matched MeSH terms: Burkholderia pseudomallei/genetics; Burkholderia pseudomallei/metabolism*
  2. Sam IC, See KH, Puthucheary SD
    J Clin Microbiol, 2009 May;47(5):1556-8.
    PMID: 19297597 DOI: 10.1128/JCM.01657-08
    A patient with a clonal infection of Burkholderia pseudomallei had subpopulations with ceftazidime and amoxicillin-clavulanate susceptibilities that differed among the clinical specimens. Resistance was associated with a novel Cys69Tyr substitution in the Ambler class A beta-lactamase. Susceptibility testing of multiple colony variants from different sites should be performed for patients with culture-confirmed melioidosis.
    Matched MeSH terms: Burkholderia pseudomallei/drug effects*; Burkholderia pseudomallei/isolation & purification
  3. Hii SYF, Ali NA, Ahmad N, Amran F
    J Med Microbiol, 2017 Nov;66(11):1623-1627.
    PMID: 29048275 DOI: 10.1099/jmm.0.000611
    Melioidosis is an endemic infectious disease in Southeast Asia and northern Australia, caused by Burkholderia pseudomallei. However, the incidence rate in Malaysia is not well documented. The high mortality rate and broad range of clinical presentations require rapid and accurate diagnosis for appropriate treatment. This study compared the efficacy of in-house IgM and IgG ELISA methods using a local B. pseudomallei strain. The diagnostic accuracy of the in-house IgG ELISA was better than that of the IgM ELISA: sensitivity (IgG: 84.71 %, IgM: 76.14 %) and specificity (IgG: 93.64 %, IgM: 90.17 %); positive predictive value (IgG: 86.75 %, IgM: 79.76 %) and negative predictive value (IgG: 92.57 %, IgM: 89.66 %); likelihood ratio (LR) [IgG: 13.32, IgM: 7.75 (LR+); IgG: 0.16, IgM: 0.26 (LR-)], and was supported by the observation of the absorbance value in comparisons between culture and serology sampling. In-house IgG ELISA was shown to be useful as an early diagnostic tool for melioidosis.
    Matched MeSH terms: Burkholderia pseudomallei/immunology; Burkholderia pseudomallei/isolation & purification
  4. Soo CI, Abdul Wahab S, Abdul Hamid F
    Respir Med Case Rep, 2015;16:54-6.
    PMID: 26744655 DOI: 10.1016/j.rmcr.2015.07.005
    Melioidosis is a serious infection, which can involve multiple systems. We report a case of pulmonary melioidosis with the initial presentation mimicking a partially treated pneumonia complicated by right-sided pleural effusion. The patient is a 49-year old man who did not respond to parenteral ceftriaxone and tazobactam/piperacillin therapy. However, upon culture and sensitivity results from blood and pleural samples isolated Burkholderia pseudomallei; antimicrobial therapy was de-escalated to parenteral ceftazidime. Within 72 h duration, his fever subsided and other respiratory symptoms improved tremendously. This case highlights the importance of early recognition of B. pseudomallei in pulmonary infection in order for prompt institution of appropriate antibiotics treatment; thus reducing morbidity and mortality.
    Matched MeSH terms: Burkholderia pseudomallei
  5. Ding CH, Hussin S, Tzar MN, Rahman MM, Ramli SR
    Pak J Med Sci, 2013 Apr;29(2):666-8.
    PMID: 24353601
    Burkholderia pseudomallei is an free-living gram-negative bacterium causing melioidosis and is endemic in Southeast Asia. A 56-year-old diabetic construction worker with a 1-month history of abdominal pain and 1-day history of high-grade fever was found to have a left non-dissecting infrarenal mycotic aortic aneurysm by abdominal computerized tomography scan. Bacteriological examination of his blood yielded Burkholderia pseudomallei. The patient was treated with right axillo-bifemoral bypass with excision of aneurysm and high-dose intravenous ceftazidime for two weeks, followed by oral trimethoprim/sulfamethoxazole and oral doxycycline for a minimum of five months.
    Matched MeSH terms: Burkholderia pseudomallei
  6. Embi N, Devarajoo D, Mohamed R, Ismail G
    World J Microbiol Biotechnol, 1993 Jan;9(1):91-6.
    PMID: 24419848 DOI: 10.1007/BF00656525
    The optimization and development of an ELISA-disc procedure for the detection of antibodies to whole cell surface antigens and purified exotoxin ofPseudomonas pseudomallei is described. Comparison of the serum agglutination test (SAT), the serum based enzyme-linked immunosorbent assay (ELISA) and the ELISA-disc procedures used on goat and human sera demonstrated a high correlation in their ability to detect antibodies specific forP. pseudomallei antigens. A serological survey using the ELISA-disc method was carried out on a normal human population in Sabah, Malaysia, an area known to be endemic for melioidosis. The prevalances of antibodies towards cell surface antigens and exotoxin ofP. pseudomallei were 28% and 8%, respectively. As a procedure, the ELISA-disc technique reported here is technically simple and provides savings in costs and is thus deemed suitable for seroepidemiological surveillance of melioidosis in remote areas of South-East Asia.
    Matched MeSH terms: Burkholderia pseudomallei
  7. Selvam K, Khalid MF, Mustaffa KMF, Harun A, Aziah I
    Microorganisms, 2021 Mar 30;9(4).
    PMID: 33808203 DOI: 10.3390/microorganisms9040711
    Melioidosis is a severe disease caused by Burkholderia pseudomallei (B. pseudomallei), a Gram-negative environmental bacterium. It is endemic in Southeast Asia and Northern Australia, but it is underreported in many other countries. The principal routes of entry for B. pseudomallei are skin penetration, inhalation, and ingestion. It mainly affects immunocompromised populations, especially patients with type 2 diabetes mellitus. The laboratory diagnosis of melioidosis is challenging due to its non-specific clinical manifestations, which mimic other severe infections. The culture method is considered an imperfect gold standard for the diagnosis of melioidosis due to its low sensitivity. Antibody detection has low sensitivity and specificity due to the high seropositivity among healthy people in endemic regions. Antigen detection using various proteins has been tested for the rapid determination of B. pseudomallei; however, it presents certain limitations in terms of its sensitivity and specificity. Therefore, this review aims to frame the present knowledge of a potential target known as the Burkholderia invasion protein D (BipD), including future directions for its detection using an aptamer-based sensor (aptasensor).
    Matched MeSH terms: Burkholderia pseudomallei
  8. Luan OG, Yam H, Samian R, Wajidi MFF, Mahadi NM, Mohamad S, et al.
    Trop Life Sci Res, 2017 Jul;28(2):57-74.
    PMID: 28890761 MyJurnal DOI: 10.21315/tlsr2017.28.2.5
    Burkholderia pseudomallei is a soil-dwelling bacterium that causes a globally emerging disease called melioidosis. Approximately one third of the in silico annotated genes in its genome are classified as hypothetical genes. This group of genes is difficult to be functionally characterised partly due to the absence of noticeable phenotypes under conventional laboratory settings. A bioinformatic survey of hypothetical genes revealed a gene designated as BPSL3393 that putatively encodes a small protein of 11 kDA with a CoA binding domain. BPSL3393 is conserved in all the B. pseudomallei genomes as well as various in other species within the genus Burkholderia. Taking into consideration that CoA plays a ubiquitous metabolic role in all life forms, characterisation of BPSL3393 may uncover a previously over-looked metabolic feature of B. pseudomallei. The gene was deleted from the genome using a double homologous recombination approach yielding a null mutant. The BPSL3393 mutant showed no difference in growth rate with the wild type under rich and minimal growth conditions. An extensive metabolic phenotyping test was performed involving 95 metabolic substrates. The deletion mutant of BPSL3393 was severely impaired in its ethanolamine metabolism. The growth rate of the mutant was attenuated when ethanolamine was used as the sole carbon source. A transcriptional analysis of the ethanolamine metabolism genes showed that they were down-regulated in the BPSL3393 mutant. This seemed to suggest that BPSL3393 functions as a positive regulator for ethanolamine metabolism.
    Matched MeSH terms: Burkholderia pseudomallei
  9. Yip CH, Ghazali AK, Nathan S
    Biochem Soc Trans, 2020 04 29;48(2):569-579.
    PMID: 32167134 DOI: 10.1042/BST20190836
    Burkholderia pseudomallei (Bp) is the causative agent of melioidosis, a disease of the tropics with high clinical mortality rates. To date, no vaccines are approved for melioidosis and current treatment relies on antibiotics. Conversely, common misdiagnosis and high pathogenicity of Bp hamper efforts to fight melioidosis. This bacterium can be isolated from a wide range of niches such as waterlogged fields, stagnant water bodies, salt water bodies and from human and animal clinical specimens. Although extensive studies have been undertaken to elucidate pathogenesis mechanisms of Bp, little is known about how a harmless soil bacterium adapts to different environmental conditions, in particular, the shift to a human host to become a highly virulent pathogen. The bacterium has a large genome encoding an armory of factors that assist the pathogen in surviving under stressful conditions and assuming its role as a deadly intracellular pathogen. This review presents an overview of what is currently known about how the pathogen adapts to different environments. With in-depth understanding of Bp adaptation and survival, more effective therapies for melioidosis can be developed by targeting related genes or proteins that play a major role in the bacteria's survival.
    Matched MeSH terms: Burkholderia pseudomallei
  10. Zainal Abidin H, Muhd Besari A, Nadarajan C, Wan Shukeri WF, Mazlan MZ, Chong SE, et al.
    IDCases, 2017;8:63-65.
    PMID: 28417070 DOI: 10.1016/j.idcr.2017.03.010
    In Malaysia, melioidosis is commonly encountered as this infection is known as part of the endemic area for the disease. Managing cases of positive Burkholderia pseudomallei infection can involve multidisciplinary unit mainly, microbiologist, infectious disease team and intensive care as it may be quite difficult to distinguish melioidosis from a number of other diseases on the clinical setting alone. Laboratory diagnosis plays a vital role in determining the direction of management. Investigations such as culture, polymerase chain reaction (PCR) and serology should be evaluated once the disease is suspected. In this particular case, the patient is a young adult involved in a road traffic accident. Unlike any other cases with melioidosis, he had no potential risk factors which may have contributed to the severity of the disease and it is likely that the site of the accident was the source of acquisition of this gram negative bacterium.
    Matched MeSH terms: Burkholderia pseudomallei
  11. Lim MP, Firdaus-Raih M, Nathan S
    Front Microbiol, 2016;7:1436.
    PMID: 27672387 DOI: 10.3389/fmicb.2016.01436
    Burkholderia pseudomallei, the causative agent of melioidosis, is among a growing number of bacterial pathogens that are increasingly antibiotic resistant. Antimicrobial peptides (AMPs) have been investigated as an alternative approach to treat microbial infections, as generally, there is a lower likelihood that a pathogen will develop resistance to AMPs. In this study, 36 candidate Caenorhabditis elegans genes that encode secreted peptides of <150 amino acids and previously shown to be overexpressed during infection by B. pseudomallei were identified from the expression profile of infected nematodes. RNA interference (RNAi)-based knockdown of 12/34 peptide-encoding genes resulted in enhanced nematode susceptibility to B. pseudomallei without affecting worm fitness. A microdilution test demonstrated that two peptides, NLP-31 and Y43C5A.3, exhibited anti-B. pseudomallei activity in a dose dependent manner on different pathogens. Time kill analysis proposed that these peptides were bacteriostatic against B. pseudomallei at concentrations up to 8× MIC90. The SYTOX green assay demonstrated that NLP-31 and Y43C5A.3 did not disrupt the B. pseudomallei membrane. Instead, gel retardation assays revealed that both peptides were able to bind to DNA and interfere with bacterial viability. In parallel, microscopic examination showed induction of cellular filamentation, a hallmark of DNA synthesis inhibition, of NLP-31 and Y43C5A.3 treated cells. In addition, the peptides also regulated the expression of inflammatory cytokines in B. pseudomallei infected macrophage cells. Collectively, these findings demonstrate the potential of NLP-31 and Y43C5A.3 as anti-B. pseudomallei peptides based on their function as immune modulators.
    Matched MeSH terms: Burkholderia pseudomallei
  12. Zhu X, Chen H, Li S, Wang LC, Wu DR, Wang XM, et al.
    Front Microbiol, 2020;11:778.
    PMID: 32457710 DOI: 10.3389/fmicb.2020.00778
    Melioidosis is a common infectious disease in Southeast Asia and Northern Australia. In Hainan, several cases have been reported, but no systematic study has yet been done on the molecular epidemiology profiles of the organism. An investigation of the molecular epidemiology links and population structure of Burkholderia pseudomallei would help to better understand the clonally of the isolates and differences among them. In this study, multilocus variable-number tandem repeat analysis (MLVA), and multilocus sequence typing (MLST) were applied to examine the epidemiological relatedness and population structure of 166 B. pseudomallei isolates obtained during 2002-2014 in Hainan, China. Both the MLVA_4 and MLST approaches had high discriminatory power for this population, with diversity indices of 0.9899 and 0.9457, respectively. However, the MLVA_4 assay showed a higher discriminatory power than the MLST approach, and a variable-number tandem repeat (VNTR3 933) found by the MLVA approach was the most useful in discriminating strains from this province. A total of 166 strains yielded 99 MLVA_4 genotypes, of which 34 genotypes were shared by 101 isolates, for a clustering rate of 60.8% (101/166), which suggested that some cases may have a common source. Additionally, 65 isolates showed distinct genotypes, indicating that more than 39.2% (65/166) of melioidosis cases in Hainan had epidemiologically unrelated or sporadic characteristics. The 166 isolates were resolved into 48 STs, of which five STs (ST55, -70, -46, -50, and -58) were here found to be predominant. Phylogenetic analysis of 116 isolates conducted using the eBURST v3 segregated the 48 STs into eight groups with ST50 as predicted founder, and 21 STs were found to be singletons, which suggest that the strains in the Hainan region represent a high diversity of ST clones, indicating that many B. pseudomallei clone groups are endemic to this region. Moreover, ST50 had 5 SLV, 7 DLV, 6 TLV, and 29 satellite STs and formed a radial expansion pattern, suggesting that the melioidosis epidemic in this study was mainly caused by the clonal expansion of ST 50. Phylogenetic analysis on global scale suggests that China's isolates are closely related to isolates from Southeast Asia, particularly from Thailand and Malaysia.
    Matched MeSH terms: Burkholderia pseudomallei
  13. Chua KH, Tan EW, Chai HC, Puthucheary SD, Lee PC, Puah SM
    PeerJ, 2020;8:e9238.
    PMID: 32518734 DOI: 10.7717/peerj.9238
    Background: Burkholderia pseudomallei causes melioidosis, a serious illness that can be fatal if untreated or misdiagnosed. Culture from clinical specimens remains the gold standard but has low diagnostic sensitivity.

    Method: In this study, we developed a rapid, sensitive and specific insulated isothermal Polymerase Chain Reaction (iiPCR) targeting bimA gene (Burkholderia Intracellular Motility A; BPSS1492) for the identification of B. pseudomallei. A pair of novel primers: BimA(F) and BimA(R) together with a probe were designed and 121 clinical B. pseudomallei strains obtained from numerous clinical sources and 10 ATCC non-targeted strains were tested with iiPCR and qPCR in parallel.

    Results: All 121 B. pseudomallei isolates were positive for qPCR while 118 isolates were positive for iiPCR, demonstrating satisfactory agreement (97.71%; 95% CI [93.45-99.53%]; k = 0.87). Sensitivity of the bimA iiPCR/POCKIT assay was 97.52% with the lower detection limit of 14 ng/µL of B. pseudomallei DNA. The developed iiPCR assay did not cross-react with 10 types of non-targeted strains, indicating good specificity.

    Conclusion: This bimA iiPCR/POCKIT assay will undoubtedly complement other methodologies used in the clinical laboratory for the rapid identification of this pathogen.

    Matched MeSH terms: Burkholderia pseudomallei
  14. Zulpa AK, Barathan M, Iyadorai T, Chandramathi S, Vellasamy KM, Vadivelu J, et al.
    Trop Biomed, 2021 Jun 01;38(2):180-185.
    PMID: 34172708 DOI: 10.47665/tb.38.2.055
    Acute myeloid leukemia (AML) is a malignant disease progressed from abnormal production of immature myeloid cells, which is often associated with concurrent infections after diagnosis. It was widely established that infections are the major contributors to mortality in this group due to the prevalency of neutropenia. Gram-negative Burkholderia pseudomallei is the causative agent of melioidosis. This disease had been reported in several neutropenic cancer patients undergoing chemotherapy resulting in severe clinical presentations and high mortalities which is in need of critical attention. Studies show that cytokines are important mediators of melioidosis progression and low neutrophil counts are associated with progression of its severity. However, to date, there are no reports on cytokine production in neutropenic cancer patients who are prone to melioidosis. Hence, here we assessed the cytokine production in neutropenic AML patients by introducing B. pseudomallei to their peripheral blood mononuclear cell (PBMC) culture in vitro. We observed that inflammatory response related cytokines namely TNF-α, IFN-γ IL-6 and IL-10 were highly circulated in infected PBMCs suggesting that these cytokines may play important roles in the progression of severity in melioidosis infected neutropenic patients.
    Matched MeSH terms: Burkholderia pseudomallei
  15. Nor NM, Baseri MM
    Curr. Opin. Infect. Dis., 2015 Apr;28(2):133-8.
    PMID: 25706913 DOI: 10.1097/QCO.0000000000000150
    We reviewed current literature on four different skin and subcutaneous infections which are often touted as 'emerging diseases' of south-east Asia, namely melioidosis, penicilliosis, sporotrichosis and Mycobacterium marinum infection. Lack of consensus treatment guidelines, high treatment costs and limited investigative capability in certain endemic areas are among the challenges faced by managing physicians. With the increase in borderless travelling, it is hoped that this review will facilitate better understanding and heighten the clinical suspicion of such infections for clinicians in other parts of the world.
    Matched MeSH terms: Burkholderia pseudomallei/isolation & purification
  16. Sulaiman H, Ponnampalavanar S, Mun KS, Italiano CM
    BMC Infect Dis, 2013 Nov 09;13:527.
    PMID: 24209898 DOI: 10.1186/1471-2334-13-527
    BACKGROUND: Infections due to Mycobacterium tuberculosis, Burkholderia pseudomallei and non-typhoidal Salmonella cause significant morbidity and mortality throughout the world. These intracellular pathogens share some common predisposing factors and clinical features. Co-infection with two of these organisms has been reported previously but, to our knowledge, this is the first time that infection with all three has been reported in one person.

    CASE PRESENTATION: In September 2010, a 58-year-old diabetic Malaysian male presented with fever and a fluctuant mass on the right side of his neck. B. pseudomallei was isolated from an aspirate of this lesion and there was radiological evidence of disseminated infection in the liver and spleen. The recurrence of clinical symptoms over ensuing months prompted further aspiration and biopsy of a cervical abscess and underlying lymph nodes. Salmonella enterica serovar Stanley and then M. tuberculosis were identified from these specimens by culture and molecular methods. The patient responded to targeted medical management of each of these infections.

    CONCLUSION: In endemic settings, a high index of suspicion and adequate tissue sampling are imperative in identifying these pathogenic organisms. Diabetes was identified as a predisposing factor in this case while our understanding of other potential risk factors is evolving.

    Matched MeSH terms: Burkholderia pseudomallei/isolation & purification
  17. Hara Y, Chin CY, Mohamed R, Puthucheary SD, Nathan S
    BMC Infect Dis, 2013;13:165.
    PMID: 23556548 DOI: 10.1186/1471-2334-13-165
    Burkholderia pseudomallei, the causative agent of melioidosis, is endemic to Southeast Asia and northern Australia. Clinical manifestations of disease are diverse, ranging from chronic infection to acute septicaemia. The current gold standard of diagnosis involves bacterial culture and identification which is time consuming and often too late for early medical intervention. Hence, rapid diagnosis of melioidosis is crucial for the successful management of melioidosis.
    Matched MeSH terms: Burkholderia pseudomallei/immunology*
  18. Su YC, Wan KL, Mohamed R, Nathan S
    Vaccine, 2010 Jul 12;28(31):5005-11.
    PMID: 20546831 DOI: 10.1016/j.vaccine.2010.05.022
    Burkholderia pseudomallei is resistant to a wide range of antibiotics, leading to relapse and recrudescence of melioidosis after cessation of antibiotic therapy. More effective immunotherapies are needed for better management of melioidosis. We evaluated the prophylactic potential of the immunogenic outer membrane protein Omp85 as a vaccine against murine melioidosis. Immunization of BALB/c mice with recombinant Omp85 (rOmp85) triggered a Th2-type immune response. Up to 70% of the immunized animals were protected against infectious challenge of B. pseudomallei with reduced bacterial load in extrapulmonary organs. Mouse anti-rOmp85 promoted complement-mediated killing and opsonophagocytosis of B. pseudomallei by human polymorphonuclear cells. In conclusion, we demonstrated that B. pseudomallei Omp85 is potentially able to induce protective immunity against melioidosis.
    Matched MeSH terms: Burkholderia pseudomallei/immunology*
  19. Zulkiflee AB, Prepageran N, Philip R
    Am J Otolaryngol, 2008 Jan-Feb;29(1):72-4.
    PMID: 18061838 DOI: 10.1016/j.amjoto.2007.02.004
    INTRODUCTION: Melioidosis is a life-threatening disease caused by B. pseudomallei. It is endemic in Southeast Asia with a few reports from the Western world. It is transmitted via inhalation, ingestion or direct contact with an open wound. Clinically it may present with local or systemic symptoms. Mortality rate is very high in systemic disease; but local infection is usually mild, which causes delay in seeking medical attention.
    CASE REPORT: We report a case of neck melioidosis presenting as a parapharyngeal abscess that was successfully managed with incision and drainage and intravenous ceftazidime and co-trimoxazole for 6 weeks followed by eradication therapy with oral co amoxiclav.
    CONCLUSION: Neck melioidosis must be considered one of differential diagnoses for "cold abscesses" of the neck, especially in an endemic area, in Asian migrants, or in those with history of previous visit from the endemic regions.
    Matched MeSH terms: Burkholderia pseudomallei/isolation & purification
  20. Asiah K, Hanifah YA, Norzila MZ, Hasniah L, Rusanida A
    J Paediatr Child Health, 2006 Apr;42(4):217-8.
    PMID: 16630326
    We report a 17-year-old Malay boy with cystic fibrosis who over a 14-month period experienced worsening respiratory symptoms and deteriorating lung function. Burkholderia pseudomallei was eventually isolated from his sputum. He improved clinically following treatment for meliodosis and his lung function returned to normal.
    Matched MeSH terms: Burkholderia pseudomallei/isolation & purification*
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links