Displaying all 17 publications

Abstract:
Sort:
  1. Prevalence of antibodies to Pseudomonas pseudomallei exotoxin and whole cell antigens in military personnel in Sabah and Sarawak, Malaysia
    Embi N, Suhaimi A, Mohamed R, Ismail G
    Microbiol. Immunol., 1992;36(8):899-904.
    PMID: 1474938
    Sera from 420 military personnel serving in Sabah and Sarawk, Malaysia, were tested for antibodies to Pseudomonas pseudomallei exotoxin and whole cell antigens by enzyme-linked immunosorbent assay procedure (ELISA). Data showed that 54.4% of serum samples were positive for antibodies to P. pseudomallei exotoxin and 65.7% were positive for antibodies to the whole cell antigens. Samples gave much lower titers for anti-exotoxin antibodies compared to titers against crude whole cell antigens. The incidence of antibody to exotoxin was highest in the age groups ranging from 26 to 32 years, where the positive rates were higher than 40% and 30% for military personnel serving in Sarawak and Sabah, respectively.
  2. An ELISA-disc procedure for antibodies toPseudomonas pseudomallei: application for a serological study of melioidosis in an endemic area
    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.
  3. Resistance of Pseudomonas pseudomallei to normal human serum bactericidal action
    Ismail G, Razak N, Mohamed R, Embi N, Omar O
    Microbiol. Immunol., 1988;32(7):645-52.
    PMID: 3193910
    The effect of human normal serum (HNS) on Pseudomonas pseudomallei was determined. It is apparent from our data that the organism is resistant to the normal serum bactericidal mechanism. Ancillary experiments to confirm this serum-resistant property of P. pseudomallei were done by examining the effects of growth phase conditions of the bacteria (i.e., logarithmic and stationary phases) and different buffered systems used as diluent in our bactericidal assay. Results obtained showed similar degree of resistance to serum bactericidal killing by 5 strains of the organisms tested. The possible survival advantage of serum-resistance property to P. pseudomallei as bacterial pathogens known to invade the blood stream is discussed.
  4. Inhibition of macromolecular synthesis in cultured macrophages by Pseudomonas pseudomallei exotoxin
    Mohamed R, Nathan S, Embi N, Razak N, Ismail G
    Microbiol. Immunol., 1989;33(10):811-20.
    PMID: 2615673
    Pseudomonas pseudomallei exotoxin was found to be a potent inhibitor of protein and DNA synthesis in cultured macrophages. Inhibition of DNA synthesis occurred at toxin concentrations as low as 1-2 micrograms/ml and inhibition of 3H-thymidine uptake was almost complete at concentrations of 8 micrograms/ml or more. A close correlation between cell damage and inhibition by DNA synthesis was observed. For protein synthesis, inhibition was obtained at much lower doses (0.06-2.0 micrograms/ml) of the toxin. At similar toxin concentrations, DNA synthesis was marginally affected. Further, it was shown that protein synthesis inhibition occurred almost immediately after incubation, reaching its maximal inhibitory effect of 70% after 6 hr. DNA synthesis, however, was minimally affected by a similar toxin concentration even after 10 hr of incubation. The inhibition of macromolecular synthesis in macrophages by P. pseudomallei exotoxin may be relevant to its modulatory effect on the host defense mechanism.
  5. Convenient and versatile DNA extraction using agarose plugs for ribotyping of problematic bacterial species
    Nair S, Karim R, Cardosa MJ, Ismail G, Pang T
    J Microbiol Methods, 1999 Oct;38(1-2):63-7.
    PMID: 10520586
    We describe a convenient, versatile and safe method for preparing bacterial DNA for ribotyping analysis. In this method, extraction of bacterial DNA from Salmnonella typhi and Burkholderia pseudomallei. and subsequent restriction endonuclease digestion, was performed in agarose blocks/plugs thus minimizing shearing and loss of DNA, problems commonly associated with liquid phase phenol extraction. Digested DNA in the plugs was then electrophoresed directly, transferred to nylon membranes and hybridized with labeled rDNA probes in the usual manner to provide reproducible restriction patterns. This method is particularly useful for bacterial species where standard DNA extraction in the liquid phase using phenol has been problematic (e.g. B. pseudomallei) but can be used for any bacterial species. The DNA extracted within the agarose plugs can be stored for long periods and can be used in other, widely-used typing methods such as pulsed-field gel electrophoresis (PFGE) and PCR-based techniques. Embedding live cells directly in agarose plugs also minimizes the risk of exposure to these virulent human pathogens among laboratory workers.
  6. Antibody to Pseudomonas pseudomallei exotoxin in sheep exposed to natural infection
    Ismail G, Mohamed R, Rohana S, Sharifah HS, Embi N
    Vet Microbiol, 1991 May;27(3-4):277-82.
    PMID: 1882505
    Specific antibody to Pseudomonas pseudomallei exotoxin was detected in sheep sera exposed to natural infection. An enzyme-linked immunosorbent assay (ELISA) was used. Serum antitoxin was present in 49.3% of sera obtained from a flock of sheep naturally exposed to P. pseudomallei infection. Among these sera, 17.0% gave titers of 10,000. In contrast, serum antitoxin was present in only 6.0% of sera collected from sheep kept on a melioidosis-free farm. The ELISA reactivity of all positive sera could be completely absorbed with purified P. pseudomallei exotoxin. Similarly, preincubation of the exotoxin-coated wells with specific antiserum inhibited the ELISA reactivity of sheep sera. The results indicate that exotoxin is produced in vivo during infection by P. pseudomallei.
  7. Fulltext Glycogen synthase kinase-3β inhibition improved survivability of mice infected with Burkholderia pseudomallei
    Tay TF, Maheran M, Too SL, Hasidah MS, Ismail G, Embi N
    Trop Biomed, 2012 Dec;29(4):551-67.
    PMID: 23202600
    The disease melioidosis, caused by the soil bacteria Burkholderia pseudomallei, often manifests as acute septicemia with high fatality. Glycogen synthase kinase-3β (GSK3β) plays a key role during the inflammatory response induced by bacteria. We used a murine model of acute melioidosis to investigate the effects of LiCl, a GSK3 inhibitor on experimental animal survivability as well as TNF-α, IL-1β, IFN-γ, IL-10 and IL-1Ra cytokine levels in blood, lung, liver and spleen of B. pseudomallei-infected mice. Our results showed that administration of 100 μg/g LiCl improved survivability of mice infected with 5 X LD50 of B. pseudomallei. Bacterial counts in spleen, liver and lungs of infected mice administered with LiCl were lower than non-treated controls. Our data also revealed that GSK3β is phosphorylated in the spleen, liver and lung of animals infected with B. pseudomallei. However in infected animals administered with LiCl, higher levels of pGSK3 were detected in the organs. Levels of proinflammatory cytokines (TNF-α, IL-1β and IFN-γ) and anti-inflammatory cytokines (IL-10 and IL-1Ra) in sera and organs tested were elevated significantly following B. pseudomallei infection. With GSK3β inhibition, pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β) were significantly decreased in all the samples tested whilst the levels of anti-inflammatory cytokines, IL-10 (spleen and lung) and IL-1Ra (spleen, liver and sera) were further elevated. This study represents the first report implicating GSK3β in the modulation of cytokine production during B. pseudomallei infection thus reiterating the important role of GSK3β in the inflammatory response caused by bacterial pathogens.
  8. Anemia in remote interior communities in Sarawak, Malaysia
    Sagin DD, Ismail G, Mohamad M, Pang EK, Sya OT
    Southeast Asian J Trop Med Public Health, 2002 Jun;33(2):373-7.
    PMID: 12236440
    A cross-sectional survey of 365 individuals, (51.9% males, 48.1% females; ages 5-85 years), from five remote interior communities in upper Rejang River basin Sarawak, Malaysia, found 24.4% were anemic. The range and mean of Hb concentration in male and female were: 7.2-17.0 mg/ml and 13.7 mg/ml and 7.9-15.7 mg/ml and 12.9 mg/ml respectively. Amongst the five tribes surveyed, the prevalence of anemia (range: 10.6-46.7%), was higher among the Penans (46.7%), Kenyahs (31.1%), Kajangs (27.8%) and Kayans (19.3%), than amongst the Ukits (10.6%). Anemia is more common among males >40 years and among adolescents and young reproductive females, as well as elderly females > 61 years old. Of the 83 anemic individuals, 6.0% and 3.6% had Trichuris trichiura or hookworm respectively; however there is no clear association with intestinal worm infection.
  9. Schistosomiasis malayensis-like infection among the Penan and other interior tribes (Orang Ulu) in upper Rejang River Basin Sarawak Malaysia
    Sagin DD, Ismail G, Fui JN, Jok JJ
    Southeast Asian J Trop Med Public Health, 2001 Mar;32(1):27-32.
    PMID: 11485090
    A serosurvey of various indigenous interior tribes (Orang Ulu) in upper Rejang River Basin Sarawak Malaysia, the site of a multibillion Ringgit hydroelectric power project, found 6.8% of the individual surveyed were seropositive for schistosomiasis, as determined by ELISA method using the soluble egg antigen of Schistosoma malayensis Baling strain. In all age group, the seroprevalence rate is higher (9.5%) in males than in females (4.5%) except for the 31-40 age group. Seroprevalence of schistosomiasis was found to increase with age with the above 60 age group having the highest rate followed by the 31-40 age group. Seroprevalence rate among the tribes ranges from 4.1% among the Penan to 11.6% among the Kajang. There was no seroevidence of schistosomiasis among the Ukits. A snail survey found four snail species including Brotia species, the intermediate host of the lung fluke Paragonimus westermani, however no schistosome snail host was identified. Although schistosomiasis malayensis-like infection may be endemic in the area, its public health significance remains undetermined.
  10. Rickettsial infection in five remote Orang Ulu villages in upper Rejang River, Sarawak, Malaysia
    Sagin DD, Ismail G, Nasian LM, Jok JJ, Pang EK
    Southeast Asian J Trop Med Public Health, 2000 Dec;31(4):733-5.
    PMID: 11414421
    People in 5 Orang Ulu villages in Sarawak, Malaysia were tested for rickettsial infection by Weil-Felix reaction and by indirect immunoperoxidase reaction. Of those surveyed 9.6% were positive for typhus. Of the positives, 3.8% were positive for tick typhus (7/11), scrub typhus (4/11) or endemic typhus (1/11). The incidence of typhus was higher among semi-nomadic Penans compared with the settled Kayans.
  11. Fulltext Epidemiological screening of lymphatic filariasis among immigrants using dipstick colloidal dye immunoassay
    Wan Omar A, Sulaiman O, Yusof S, Ismail G, Fatmah MS, Rahmah N, et al.
    Malays J Med Sci, 2001 Jul;8(2):19-24.
    PMID: 22893756
    We have recently reported that a dipstick colloidal dye immunoassay (DIA) that detect parasite antigens in human serum is sensitive and specific for the diagnosis of active infection of lymphatic filariasis. Rabbit polyclonal antibodies (RbBmCAg) labelled with a commercial dye, palanil navy blue was used to detect filarial antigenemia among Indonesian and Bangladeshi immigrant workers (N= 630) at oil palm estates at Hulu Trengganu District, Peninsular Malaysia. Microfilaremia with Brugia malayi were detected in 51 (8.10 %) individuals, of which 42 (6.67 %) were among the Indonesians and 9 (1.98 %) among the Bangladeshis. Microfilaremia with Wuchereria bancrofti were detected in 33 (5.24 %) individuals of which 15 (2.38 %) were among the Indonesians and 18 (2.86 %) among the Bangladeshis workers. The DIA detected 96 (15.24 %) antigenemic cases which comprise of all the microfilaremic cases and 15 (2.38 %) amicrofilaremic cases. The amicrofilaremic cases with filarial antigenemia consisted of 9 (1. 43 %) Indonesians and 6 (0.95%) Bangladeshis. We have used 6 ul of the RbBmCAg and diluted (1:10) patients' sera per dipstick which make the DIA reagent conservative. The DIA is a rapid test and can be read in approximate 2 hours.. Additionally, coloured dots developed in the DIA can be qualitatively assessed visually for intensity. The DIA does not require sophisticated equipment or radioactivity, and therefore suitable for field application.
  12. Short report: Electron microscopic demonstration of extracellular structure of Burkholderia pseudomallei
    Puthucheary SD, Vadivelu J, Ce-Cile C, Kum-Thong W, Ismail G
    Am J Trop Med Hyg, 1996 Mar;54(3):313-4.
    PMID: 8600773
    The occurrence of latency and relapse in human melioidosis suggests adaptations by Burkholderia pseudomallei that help to avoid the human immune response. Ruthenium red-stained preparations of bacterial cultures viewed by electron microscopy revealed three morphologically distinct variants; one with a very marked and another with a less electron-dense layer surrounding the cell wall, and a third variety devoid of such a structure. This structure may be attributable to a layer of polysaccharide, suggesting the presence of a glycocalyx that may aid in the survival of the organism during latency.
  13. Intestinal parasitic infection among five interior communities at upper Rejang River, Sarawak, Malaysia
    Sagin DD, Mohamed M, Ismail G, Jok JJ, Lim LH, Pui JN
    Southeast Asian J Trop Med Public Health, 2002 Mar;33(1):18-22.
    PMID: 12118449
    Intestinal parasitic infection among five interior communities at Bakun Valley, upper Rejang River, Sarawak, Malaysia, was investigated as part of a public health impact assessment of the proposed US$ 3 billion Bakun Hydroelectric Project. Coproparasitological examination of 355 stool samples from 7 of 16 villages representing 5 of 7 tribes in the area revealed infection rate of 41%. A higher infection rate was found among the settled Kayans (56%) than the seminomadic Penans (29%). Infection rate was high (68%) among children less than 14 years old. Trichuris trichiura accounted for more than 90% of all infections; less common were Ascaris lumbricoides, hookworms and Strongyloides stercoralis. Polyparasitism was found in 8% of the individuals surveyed with dual infection due to T. trichiura and A. lumbricoides being more common than dual infection with T. trichiura and hookworm. Women had higher infection rates (57%) than men (33%).
  14. Fulltext Enterobius vermicularis infection among children aged 1-8 years in a rural area in Malaysia
    Norhayati M, Hayati MI, Oothuman P, Azizi O, Fatmah MS, Ismail G, et al.
    Southeast Asian J Trop Med Public Health, 1994 Sep;25(3):494-7.
    PMID: 7777914
    The infection rate and relationship of enterobiasis with socio-economic status were determined in children aged 1-8 years, living in a rural area in Malaysia. Of the 178 subjects 40.4% were infected with Enterobius vermicularis. The distribution of enterobiasis among these children were analyzed in relation to age groups and sex. The rate of infection was significantly higher in older children (5-7 years). The association of enterobiasis with other factors studied such as number of persons per house, household income per months and mother's employment status were not significant. The sensitivity of three successive days anal swabs compared to a single swab was found to be statistically significant.
  15. Prevalence of Enterobius vermicularis amongst adults living in hostels by six successive day examination
    Oothuman P, Noor Hayati MI, Mastura MH, Rampal L, Jeffery J, Rubiah M, et al.
    Southeast Asian J Trop Med Public Health, 1992 Mar;23(1):82-6.
    PMID: 1523484
    The prevalence of Enterobius vermicularis in four groups of adults, all trainee public health inspectors or public health nurses, aged 18-35 years and all living in hostels on campus was studied. The modified scotch tape technique was used and the subjects were taught to do the examination on themselves to detect the presence of eggs over a period of 6 successive mornings. Each was given an elaborately illustrated diagram on how and when to take the samples and given demonstration in groups. The samples were examined by trained people. Most of the subjects took samples on 6 consecutive days. Of the 119 subjects who returned samples, the overall prevalence of E. vermicularis was 9.2% and this was thought to be high for this particular age group. This was due to the higher prevalence (19.4%) in one group, whereas in the others the range was 3.5-8.0%. Based on the samples returned on the first day none of the subjects were detected as having the infection. After examination on 3 successive days (109 subjects) 10.1% were found to be infected (chi 2 = 10.704; d. f. = 1) and after examination on 6 successive days (72 subjects) 13.9% were found to be infected (chi 2 = 3.026; d. f. = 1). There was no significance between examination over 3 successive days and 6 consecutive days (chi 2 = 0.296; d. f. = 1). There was no difference in the prevalence between males and females.(ABSTRACT TRUNCATED AT 250 WORDS)
  16. Seroprevalence of toxoplasmosis among migrant workers from different Asian countries working in Malaysia
    Chan BT, Amal RN, Hayati MI, Kino H, Anisah N, Norhayati M, et al.
    Southeast Asian J Trop Med Public Health, 2008 Jan;39(1):9-13.
    PMID: 18567437
    A serologic study of Toxoplasma antibodies among 501 foreign migrant workers in Malaysia was conducted in a plantation and detention camp. The highest prevalence rate of 46.2% was among Nepalese workers. Statistical analysis indicated the IgG positivity rate among local residents was significantly higher than the migrants studied (p < 0.05). The IgM positivity rate showed no significant difference between the two groups (p > 0.05). No significant difference in the prevalence rate was noted between the migrants and the local workers when grouped by agricultural and non-agricultural occupations (p > 0.05). The continuous introduction of these infections may influence the epidemiology and further compromise efforts in control and prevention. It is therefore important to monitor of non-notifiable diseases.
  17. Oncologist-led BRCA counselling improves access to cancer genetic testing in middle-income Asian country, with no significant impact on psychosocial outcomes
    Yoon SY, Wong SW, Lim J, Ahmad S, Mariapun S, Padmanabhan H, et al.
    J Med Genet, 2022 Mar;59(3):220-229.
    PMID: 33526602 DOI: 10.1136/jmedgenet-2020-107416
    BACKGROUND: Identifying patients with BRCA mutations is clinically important to inform on the potential response to treatment and for risk management of patients and their relatives. However, traditional referral routes may not meet clinical needs, and therefore, mainstreaming cancer genetics has been shown to be effective in some high-income and high health-literacy settings. To date, no study has reported on the feasibility of mainstreaming in low-income and middle-income settings, where the service considerations and health literacy could detrimentally affect the feasibility of mainstreaming.

    METHODS: The Mainstreaming Genetic Counselling for Ovarian Cancer Patients (MaGiC) study is a prospective, two-arm observational study comparing oncologist-led and genetics-led counselling. This study included 790 multiethnic patients with ovarian cancer from 23 sites in Malaysia. We compared the impact of different method of delivery of genetic counselling on the uptake of genetic testing and assessed the feasibility, knowledge and satisfaction of patients with ovarian cancer.

    RESULTS: Oncologists were satisfied with the mainstreaming experience, with 95% indicating a desire to incorporate testing into their clinical practice. The uptake of genetic testing was similar in the mainstreaming and genetics arm (80% and 79%, respectively). Patient satisfaction was high, whereas decision conflict and psychological impact were low in both arms of the study. Notably, decisional conflict, although lower than threshold, was higher for the mainstreaming group compared with the genetics arm. Overall, 13.5% of patients had a pathogenic variant in BRCA1 or BRCA2, and there was no difference between psychosocial measures for carriers in both arms.

    CONCLUSION: The MaGiC study demonstrates that mainstreaming cancer genetics is feasible in low-resource and middle-resource Asian setting and increased coverage for genetic testing.

Related Terms
Filters
Contact Us

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

External Links