Displaying publications 61 - 80 of 566 in total

Abstract:
Sort:
  1. Kalai Chelvam K, Yap KP, Chai LC, Thong KL
    PLoS One, 2015;10(5):e0126207.
    PMID: 25946205 DOI: 10.1371/journal.pone.0126207
    Salmonella enterica serovar Typhi (S. Typhi) is a foodborne pathogen that causes typhoid fever and infects only humans. The ability of S. Typhi to survive outside the human host remains unclear, particularly in human carrier strains. In this study, we have investigated the catabolic activity of a human carrier S. Typhi strain in both planktonic and biofilm cells using the high-throughput Biolog Phenotype MicroArray, Minimum Biofilm Eradication Concentration (MBEC) biofilm inoculator (96-well peg lid) and whole genome sequence data. Additional strains of S. Typhi were tested to further validate the variation of catabolism in selected carbon substrates in the different bacterial growth phases. The analyzes of the carbon utilization data indicated that planktonic cells of the carrier strain, S. Typhi CR0044 could utilize a broader range of carbon substrates compared to biofilm cells. Pyruvic acid and succinic acid which are related to energy metabolism were actively catabolised in the planktonic stage compared to biofilm stage. On the other hand, glycerol, L-fucose, L-rhamnose (carbohydrates) and D-threonine (amino acid) were more actively catabolised by biofilm cells compared to planktonic cells. Notably, dextrin and pectin could induce strong biofilm formation in the human carrier strain of S. Typhi. However, pectin could not induce formation of biofilm in the other S. Typhi strains. Phenome data showed the utilization of certain carbon substrates which was supported by the presence of the catabolism-associated genes in S. Typhi CR0044. In conclusion, the findings showed the differential carbon utilization between planktonic and biofilm cells of a S. Typhi human carrier strain. The differences found in the carbon utilization profiles suggested that S. Typhi uses substrates mainly found in the human biliary mucus glycoprotein, gallbladder, liver and cortex of the kidney of the human host. The observed diversity in the carbon catabolism profiles among different S. Typhi strains has suggested the possible involvement of various metabolic pathways that might be related to the virulence and pathogenesis of this host-restricted human pathogen. The data serve as a caveat for future in-vivo studies to investigate the carbon metabolic activity to the pathogenesis of S. Typhi.
    Matched MeSH terms: Typhoid Fever/microbiology
  2. Goh YL, Puthucheary SD, Chaudhry R, Bhutta ZA, Lesmana M, Oyofo BA, et al.
    J Appl Microbiol, 2002;92(6):1167-71.
    PMID: 12010557
    Subtyping of Salmonella Paratyphi A isolates from India, Pakistan, Indonesia and Malaysia was carried out by pulsed-field gel electrophoresis (PFGE) to assess the extent of genetic diversity of these isolates from different endemic countries.
    Matched MeSH terms: Paratyphoid Fever/microbiology*; Paratyphoid Fever/epidemiology
  3. Goh YL, Yasin R, Puthucheary SD, Koh YT, Lim VK, Taib Z, et al.
    J Appl Microbiol, 2003;95(5):1134-42.
    PMID: 14633043
    DNA fingerprinting of Salmonella enterica serotype Paratyphi B isolated in Malaysia during 1982-83, 1992 and 1996-2002 was carried out by pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility tests and D-tartrate utilization tests to assess the extent of genetic diversity of these isolates in Malaysia.
    Matched MeSH terms: Paratyphoid Fever/microbiology*
  4. Teh CS, Chua KH, Puthucheary SD, Thong KL
    Jpn J Infect Dis, 2008 Jul;61(4):313-4.
    PMID: 18653978
    Salmonella enterica serovar Paratyphi A is a causative agent of paratyphoid fever. The clinical syndrome caused by paratyphoid fever overlaps with other febrile illnesses and cannot be distinguished from typhoid fever. Conventional methods used for diagnosis are time consuming, costly, and labor-intensive. We evaluated the specificity, sensitivity, and application of a multiplex polymerase chain reaction (PCR) previously developed by the method (Ou, H.Y., Teh, C.S.J., Thong, K.L., et al., J. Mol. Diagn., 9, 624-630, 2007) using 6 S. Paratyphi A, 22 S. Typhi, and 85 other Salmonella serovars as well as 36 non-Salmonella strains. The detection limit of the multiplex PCR was 4 x 10(4) cfu ml(-1). In a blind test of the other 50 strains, this multiplex PCR correctly identified the only S. Paratyphi A in the panel of strains. The sensitivity of this PCR using spiked blood and stool samples was 1 x 10(5) cfu ml(-1) and 2 x 10(5) cfu ml(-1), respectively, but increased to 1 x 10(4) cfu ml(-1) and 2 x 10(3) cfu ml(-1) after 5-h enrichment. We believe that this multiplex PCR is a promising technique for the specific and sensitive detection of S. Paratyphi A in clinical, environmental, and food samples.
    Matched MeSH terms: Paratyphoid Fever/diagnosis*; Paratyphoid Fever/microbiology*
  5. Kalai Chelvam K, Chai LC, Thong KL
    Gut Pathog, 2014;6(1):2.
    PMID: 24499680 DOI: 10.1186/1757-4749-6-2
    Salmonella enterica serovar Typhi (S. Typhi) exhibits unique characteristics as an intracellular human pathogen. It causes both acute and chronic infection with various disease manifestations in the human host only. The principal factors underlying the unique lifestyle of motility and biofilm forming ability of S. Typhi remain largely unknown. The main objective of this study was to explore and investigate the motility and biofilm forming behaviour among S. Typhi strains of diverse background.
    Matched MeSH terms: Typhoid Fever
  6. Yap KP, Thong KL
    Trop Med Int Health, 2017 08;22(8):918-925.
    PMID: 28544285 DOI: 10.1111/tmi.12899
    Next-generation whole-genome sequencing has revolutionised the study of infectious diseases in recent years. The availability of genome sequences and its understanding have transformed the field of molecular microbiology, epidemiology, infection treatments and vaccine developments. We review the key findings of the publicly accessible genomes of Salmonella enterica serovar Typhi since the first complete genome to the most recent release of thousands of Salmonella Typhi genomes, which remarkably shape the genomic research of S. Typhi and other pathogens. Important new insights acquired from the genome sequencing of S. Typhi, pertaining to genomic variations, evolution, population structure, antibiotic resistance, virulence, pathogenesis, disease surveillance/investigation and disease control are discussed. As the numbers of sequenced genomes are increasing at an unprecedented rate, fine variations in the gene pool of S. Typhi are captured in high resolution, allowing deeper understanding of the pathogen's evolutionary trends and its pathogenesis, paving the way to bringing us closer to eradication of typhoid through effective vaccine/treatment development.
    Matched MeSH terms: Typhoid Fever/drug therapy; Typhoid Fever/microbiology*; Typhoid Fever/prevention & control
  7. Tang SS, Tan WS, Devi S, Wang LF, Pang T, Thong KL
    Clin Diagn Lab Immunol, 2003 Nov;10(6):1078-84.
    PMID: 14607870
    The capsular polysaccharide Vi antigen (ViCPS) is an essential virulence factor and also a protective antigen of Salmonella enterica serovar Typhi. A random 12-mer phage-displayed peptide library was used to identify mimotopes (epitope analogues) of this antigen by panning against a ViCPS-specific monoclonal antibody (MAb) ATVi. Approximately 75% of the phage clones selected in the fourth round carried the peptide sequence TSHHDSHGLHRV, and the rest of the clones harbored ENHSPVNIAHKL and other related sequences. These two sequences were also obtained in a similar panning process by using pooled sera from patients with a confirmed diagnosis of typhoid fever, suggesting they mimic immunodominant epitopes of ViCPS antigens. Binding of MAb ATVi to the mimotopes was specifically blocked by ViCPS, indicating that they interact with the same binding site (paratope) of the MAb. Data and reagents generated in this study have important implications for the development of peptide-base diagnostic tests and peptide vaccines and may also provide a better understanding of the pathogenesis of typhoid fever.
    Matched MeSH terms: Typhoid Fever/diagnosis*
  8. Teh CS, Chua KH, Thong KL
    Int J Med Sci, 2014;11(7):732-41.
    PMID: 24904229 DOI: 10.7150/ijms.7768
    The incidence of enteric fever caused by Salmonella enterica serovar Paratyphi A (S. Paratyphi A) is increasing in many parts of the world. Although there is no major outbreak of paratyphoid fever in recent years, S. Paratyphi A infection still remains a public health problem in many tropical countries. Therefore, surveillance studies play an important role in monitoring infections and the emergence of multidrug resistance, especially in endemic countries such as India, Nepal, Pakistan and China. In China, enteric fever was caused predominantly by S. Paratyphi A rather than by Salmonella enterica serovar Typhi (S. Typhi). Sometimes, S. Paratyphi A infection can evolve into a carrier state which increases the risk of transmission for travellers. Hence, paratyphoid fever is usually classified as a "travel-associated" disease. To date, diagnosis of paratyphoid fever based on the clinical presentation is not satisfactory as it resembles other febrile illnesses, and could not be distinguished from S. Typhi infection. With the availability of Whole Genome Sequencing technology, the genomes of S. Paratyphi A could be studied in-depth and more specific targets for detection will be revealed. Hence, detection of S. Paratyphi A with Polymerase Chain Reaction (PCR) method appears to be a more reliable approach compared to the Widal test. On the other hand, due to increasing incidence of S. Paratyphi A infections worldwide, the need to produce a paratyphoid vaccine is essential and urgent. Hence various vaccine projects that involve clinical trials have been carried out. Overall, this review provides the insights of S. Paratyphi A, including the bacteriology, epidemiology, management and antibiotic susceptibility, diagnoses and vaccine development.
    Matched MeSH terms: Paratyphoid Fever/microbiology; Paratyphoid Fever/epidemiology*; Paratyphoid Fever/pathology
  9. Yap KP, Gan HM, Teh CS, Baddam R, Chai LC, Kumar N, et al.
    J Bacteriol, 2012 Nov;194(21):5970-1.
    PMID: 23045488 DOI: 10.1128/JB.01416-12
    Salmonella enterica serovar Typhi is a human pathogen that causes typhoid fever predominantly in developing countries. In this article, we describe the whole genome sequence of the S. Typhi strain CR0044 isolated from a typhoid fever carrier in Kelantan, Malaysia. These data will further enhance the understanding of its host persistence and adaptive mechanism.
    Matched MeSH terms: Typhoid Fever/microbiology
  10. Yap KP, Teh CS, Baddam R, Chai LC, Kumar N, Avasthi TS, et al.
    J Bacteriol, 2012 Sep;194(18):5124-5.
    PMID: 22933756 DOI: 10.1128/JB.01062-12
    Salmonella enterica serovar Typhi is the causative agent of typhoid fever, which causes nearly 21.7 million illnesses and 217,000 deaths globally. Herein, we describe the whole-genome sequence of the Salmonella Typhi strain ST0208, isolated from a sporadic case of typhoid fever in Kuala Lumpur, Malaysia. The whole-genome sequence and comparative genomics allow an in-depth understanding of the genetic diversity, and its link to pathogenicity and evolutionary dynamics, of this highly clonal pathogen that is endemic to Malaysia.
    Matched MeSH terms: Typhoid Fever/microbiology
  11. Thin RN
    Lancet, 1976 Jan 3;1(7949):31-3.
    PMID: 54528 DOI: 10.1016/s0140-6736(76)92922-6
    Titres of melioidosis haemagglutinating antibodies of 1/40 or more were found in 18 of 905 British, Australian, and New Zealand soldiers serving in West Malaysia. Previous mild unsuspected melioidosis seemed to be responsible for these positive titres, which were more common in men exposed to surface water at work and during recreation. This accords with the current view that soil and surface water is the normal habitat of Pseudomonas pseudomallei, the causal organism. Pyrexia of unknown origin after arriving in Malaysia was significantly more common in men with titres of 1/40 or more than in the remainder. It is suggested that mild melioidosis may present as pyrexia of unknown origin. Pyrexias of unknown origin should be investigated vigorously in patients who are in or who have visited endemic areas.
    Matched MeSH terms: Fever/diagnosis; Fever/etiology
  12. The Ambulatory PS
    Family Physician, 1995;7:40-41.
    Matched MeSH terms: Fever
  13. Teng CL
    Malays Fam Physician, 2009;4(1):40.
    PMID: 25606159
    Matched MeSH terms: Fever
  14. Phua CE, Bustam AZ, Yusof MM, Saad M, Yip CH, Taib NA, et al.
    Asian Pac J Cancer Prev, 2012;13(9):4623-6.
    PMID: 23167391
    BACKGROUND: The risk of treatment-related death (TRD) and febrile neutropaenia (FN) with adjuvant taxane- based chemotherapy for early breast cancer is unknown in Malaysia despite its widespread usage in recent years. This study aims to determine these rates in patients treated in University Malaya Medical Centre (UMMC).

    PATIENTS AND METHODS: Patients who were treated with adjuvant taxane-based chemotherapy for early breast cancer stages I, II or III from 2007-2011 in UMMC were identified from our UMMC Breast Cancer Registry. The TRD and FN rates were then determined retrospectively from medical records. TRD was defined as death occurring during or within 30 days of completing chemotherapy as a consequence of the chemotherapy treatment. FN was defined as an oral temperature >38.5°C or two consecutive readings of >38.0°C for 2 hours and an absolute neutrophil count <0.5x109/L, or expected to fall below 0.5x109/L.

    RESULTS: A total of 622 patients received adjuvant chemotherapy during this period. Of these patients 209 (33.6%) received taxane-based chemotherapy. 4 taxane-based regimens were used namely the FEC-D, TC, TAC and AC-PCX regimens. The commonest regimen employed was the FEC-D regimen accounting for 79.9% of the patients. The FN rate was 10% and there was no TRD.

    CONCLUSION: Adjuvant taxane-based chemotherapy in UMMC for early breast cancer has a FN rate of 10%. Primary prophylactic G-CSF should be considered for patients with any additional risk factor for FN.

    Matched MeSH terms: Fever/chemically induced
  15. Ahmad N, Hoon ST, Ghani MK, Tee KY
    Malays J Pathol, 2012 Jun;34(1):35-9.
    PMID: 22870596 MyJurnal
    Serotyping is not sufficient to differentiate between Salmonella species that cause paratyphoid fever from the strains that cause milder gastroenteritis as these organisms share the same serotype Salmonella Paratyphi B (S. Paratyphi B). Strains causing paratyphoid fever do not ferment d-tartrate and this key feature was used in this study to determine the prevalence of these strains among the collection of S. Paratyphi B strains isolated from patients in Malaysia. A total of 105 isolates of S. Paratyphi B were discriminated into d-tartrate positive (dT+) and d-tartrate negative (dT) variants by two lead acetate test protocols and multiplex PCR. The lead acetate test protocol 1 differed from protocol 2 by a lower inoculum size and different incubation conditions while the multiplex PCR utilized 2 sets of primers targeting the ATG start codon of the gene STM3356. Lead acetate protocol 1 discriminated 97.1% of the isolates as S. Paratyphi B dT+ and 2.9% as dT while test protocol 2 discriminated all the isolates as S. Paratyphi B dT+. The multiplex PCR test identified all 105 isolates as S. Paratyphi B dT+ strains. The concordance of the lead acetate test relative to that of multiplex PCR was 97.7% and 100% for protocol 1 and 2 respectively. This study showed that S. Paratyphi B dT+ is a common causative agent of gastroenteritis in Malaysia while paratyphoid fever appears to be relatively uncommon. Multiplex PCR was shown to be a simpler, more rapid and reliable method to discriminate S. Paratyphi B than the phenotypic lead acetate test.
    Matched MeSH terms: Paratyphoid Fever/diagnosis; Paratyphoid Fever/microbiology*
  16. Gazi U, Baykam N, Karasartova D, Tosun O, Akdogan O, Yapar D, et al.
    Trop Biomed, 2022 Dec 01;39(4):587-591.
    PMID: 36602220 DOI: 10.47665/tb.39.4.016
    Crimean-Congo haemorrhagic fever (CCHF) is a severe human infection which can lead to fatal consequences. Acute CCHF patients were previously shown to exhibit frequencies of regulatory T-cell (Treg) but lower Treg-mediated suppressive activities than the healthy counterparts. This study aims is to investigate the phosphorylation levels of Foxp3 protein (master regulator of Treg cells) in CCHF patients. Blood samples collected from 18 CCHF patients and nine healthy volunteers were used to isolate peripheral blood mononuclear cells (PBMCs). Total and phosphorylated Foxp3 expression levels in the isolated PBMC samples were monitored by western blot and quantified using ImageJ software. Total Foxp3 expression levels in CCHF patients displayed decreasing trend, but not significantly. In contrast, significantly lower expression levels of phosphorylated Foxp3 were reported in CCHF patients. Our results suggest a possible association between Foxp3 dephosphorylation and CCHF pathogenesis. Nevertheless, more studies are required to evaluate the effect of Foxp3 dephosphorylation on Treg function, which would not only help to enlighten the CCHF pathogenesis but also contribute to the development of effective treatment strategies.
    Matched MeSH terms: Hemorrhagic Fever Virus, Crimean-Congo*; Hemorrhagic Fever, Crimean*
  17. Tham DWJ, Abubakar U, Tangiisuran B
    Eur J Pediatr, 2020 May;179(5):743-748.
    PMID: 31900590 DOI: 10.1007/s00431-019-03560-z
    Inappropriate use of antibiotics in human and animal is one of the causes of antimicrobial resistance. This study evaluates the prevalence and predictors of antibiotic use among pediatric patients visiting the Emergency Department (ED) in Malaysia. A retrospective cross-sectional study was conducted in the ED of a tertiary hospital. Data of children aged 2 to 11 years who visited the ED from January-May 2015 were extracted from the patient's assessment forms. A total of 549 children were included in the analysis (median age 5 years) of which 54.3% were boys. Upper respiratory tract infections (URTI) were the most common diagnosis. Antibiotic was prescribed in 43.5% of the children. Children who visited the ED during the weekend (OR, 1.65; 95% confidence interval (CI) 1.13-2.40, P = 0.009), those diagnosed with URTI (OR 3.81; 95% CI, 2.45-5.93, P fever (OR, 1.31; 95% CI, 1.15-1.48, P fever. Antimicrobial stewardship program is recommended in the pediatric ED to improve appropriate use of antibiotics.What is Known:•Use of antibiotic among children increases the risk of antibiotic resistance and adverse drug reactions.•Patient-, clinical-, and prescriber-related factors are three important domain associated with antibiotic use in children.What is New:•Fever and upper respiratory tract infections account for majority of antibiotic prescriptions.•The "weekend effect" influences the use of antibiotics in the ED while upper respiratory tract infection is the strongest predictor of antibiotic use among children visiting the ED.
    Matched MeSH terms: Fever
  18. Kqueen, Cheah Yoke, Maryam Abdulla Seif, Mohamed Ikhtifar Rafi, Lim, Wei Meng, Ling, Clemente Michael Wong Vui, Tan, Geok Yuan Annie
    MyJurnal
    Global warming is the main concern in today’s century as it comes with numerous side effects to the natural environment. Open Top Chambers (OTC) consist of metal constructions with transparent vertical side-walls and a frustum on top. An opening in the middle of the frustum allows an air exchange to reduce temperature and humidity effects in the chamber. The size of the open top chamber which is located in Universiti Putra Malaysia is slanted 60o, 50cm tall, 2.08m basal diameter hexagon chamber. The Open Top Chamber experiments were carried out to determine how much global warming has affected and is still affecting the temperature, pH, the moisture and the growth of the microbes in the tropical soil. The aim of this study is to elucidate the effects of temperature increase on the soil microbes’ population and on the pH of the soil. The study was conducted to observe the effect of heat on the population of soil microbes and the pH of the soil which was collected on the same day for 6 consecutive months. The microbes from the samples were grown on agar plates. The population of microbes on the plates were used as values were for Colony Forming Unit (CFU) value calculations. The effects of OTCs on mean temperature showed a large range of CFU values throughout the 6 months but did not differ significantly between studies. Increases in mean monthly and diurnal temperature were strongly related, indicating that the presence of warming effect by the OTCs. Such predictive power allows a better mechanistic understanding of observed biotic response to experimental warming. This study will be useful for the understanding of the global warming effect on microbes. The Open Top Chamber experiment has proven to be one of the effective model for global warming research and data collected especially on the growth of soil microbial obtained would be of great use for further experiments.
    Matched MeSH terms: Fever
  19. Tan PH, Teng XX, Gan ZY, Tan SQ
    Malays J Med Sci, 2020 Jul;27(4):139-146.
    PMID: 32863753 MyJurnal DOI: 10.21315/mjms2020.27.4.13
    Background: Appendicitis complicated with appendiceal perforation is common among children. The delay in diagnosis of appendicitis is due to children's varied presentations and their difficulty in communicating symptoms. We aimed to identify clinical factors that aid in predicting acute appendicitis (AA) and perforated appendicitis (PA) among children.

    Methods: This retrospective study involved 215 children aged 12 years and below with the initial diagnosis of AA and PA. Clinical factors studied were demographics, presenting symptoms, body temperature on admission (BTOA), white cell count (WCC), absolute neutrophil count (ANC), platelet count and urinalysis. Simple and multiple logistic regressions were used to determine the odds ratio of the statistically significant clinical factors. Results: The mean age of the included children was 7.98 ± 2.37 years. The odds of AA increased by 2.177 times when the age was ≥ 8 years (P = 0.022), 2.380 times when duration of symptoms ≥ 2 days (P = 0.011), 2.447 times with right iliac fossa (RIF) pain (P = 0.007), 2.268 times when BTOA ≥ 38 °C (P = 0.020) and 2.382 times when neutrophil percentage was ≥ 76% (P = 0.045). It decreased by 0.409 times with non-RIF pain (P = 0.007). The odds of PA was increased by 4.672 times when duration of symptoms ≥ 2 days (P = 0.005), 3.611 times when BTOA ≥ 38 °C (P = 0.015) and 3.678 times when neutrophil percentage ≥ 76% (P = 0.016). There was no significant correlation between WCC and ANC with AA and PA.

    Conclusion: Older children with longer duration of symptoms, RIF pain and higher BTOA are more likely to have appendicitis. The risk of appendiceal perforation increases with longer duration of symptoms and higher BTOA.

    Matched MeSH terms: Fever
  20. Jamal F, Mohd Salleh H, Tan SP
    World Health Forum, 1994;15(1):56-7.
    PMID: 8141979
    Matched MeSH terms: Rheumatic Fever/complications
Filters
Contact Us

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

External Links