Displaying publications 1 - 20 of 71 in total

Abstract:
Sort:
  1. Toxoplasmosis in HIV/AIDS patients: a current situation
    Nissapatorn V, Lee C, Quek KF, Leong CL, Mahmud R, Abdullah KA
    Jpn J Infect Dis, 2004 Aug;57(4):160-5.
    PMID: 15329448
    The seroprevalence of toxoplasmosis among 505 of human immunodeficiency virus (HIV)/AIDS patients was 226 (44.8%; 95% CI 42.64-51.76): 27 (47.4%) and 199 (44.4%) showed Toxoplasma seropositivity with and without toxoplasmic encephalitis (TE), respectively (P <0.05). The majority of these patients were in the 25-34 age group (44 versus 39%), male (86 versus 76%), and Chinese (49 versus 53%), though no statistical significance was found between the two. Significant differences between these two groups were noted, however, in terms of marital status, occupation, and present address. The heterosexual exhibited the most frequent behavior at risk for HIV infection, and accounted for 51 and 59% of patients with and without TE, respectively. Only 17/260 (6.5%) and 1/137 (0.7%) of them later acquired TE after receiving primary chemoprophylaxis (cotrimoxazole) and antiretroviral therapy including HAART (P <0.05). Fifty-seven (11.3%) out of those 505 patients were diagnosed with AIDS-related TE. The most common clinical manifestation was headache (56%). The computed tomography scan findings showed most lesions to be multiple (96.4%), hypodense (66.7%), and in the parietal region (39.3%). Twenty-seven (47.4%) patients had chronic (latent) Toxoplasma infection as evidenced by seropositivity for anti-Toxoplasma (IgG) antibody. At the time of diagnosis, the range of CD4 cell count was from 0-239 with a median of 25 cells/cumm. We also found that a CD4 count of less than 100 cells/cumm was significantly associated with development of TE (P <0.05). Clinical outcomes showed that among those who survived, 21 (36.8%), 16 (28.1%), and 2 (3.5%) of patients had completed treatment, transferred out, and were lost to follow up, respectively. Unfortunately, 18 (31.6%) of the cases were officially pronounced dead. Overall, 7 (12.3%) patients were detected as recurrent TE in this study.
    Matched MeSH terms: Antibodies, Protozoan/blood
  2. Fulltext Occurrence of Toxoplasma gondii antibodies and associated risk factors in women in selected districts of Punjab province, Pakistan
    Ali S, Amjad Z, Khan TM, Maalik A, Iftikhar A, Khan I, et al.
    Parasitology, 2020 Sep;147(10):1133-1139.
    PMID: 32517832 DOI: 10.1017/S0031182020000967
    Toxoplasmosis is a parasitic zoonotic disease caused by Toxoplasma (T.) gondii. Limited data are available on the occurrence of T. gondii in women especially pregnant women in Pakistan. The present study aimed to determine the occurrence and risk factors associated with T. gondii in pregnant and non-pregnant women in Punjab Province, Pakistan. A cross-sectional study was conducted and 593 samples were collected from pregnant (n = 293) and non-pregnant (n = 300) women of District Headquarter Hospitals of Chiniot, Faisalabad, Jhang and Okara, Pakistan. Data related to demographic parameters and risk factors were collected using a pretested questionnaire on blood sampling day. Serum samples were screened for antibodies (IgG) against T. gondii using ELISA. A univariant and binomial logistic regression was applied to estimate the association between seropositive and explanatory variables considering the 95% confidence interval. P value ⩽0.05 was considered statistically significant for all analysis. Out of 593, 44 (7.42%) women were seropositive for T. gondii IgG antibodies. Occupation, age, sampling location, socioeconomic status, contact with cat, pregnancy status and trimester of pregnancy were significantly associated with seropositivity for T. gondii antibodies. Location and trimester of pregnancy were identified as potential risk factors for T. gondii seropositivity based on binomial logistic regression. Toxoplasma gondii is prevalent in pregnant and non-pregnant women. Therefore, now a necessitated awareness is required to instruct the individuals about these infectious diseases (toxoplasmosis) and their control strategies to maintain the health of human population. Moreover, health awareness among public can help the minimization of T. gondii infection during pregnancy and subsequent risk of congenital toxoplasmosis.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  3. Fulltext IgG avidity assay: a tool for excluding acute toxoplasmosis in prolonged IgM titer sera from pregnant women
    Emelia O, Rahana AR, Mohamad Firdaus A, Cheng HS, Nursyairah MS, Fatinah AS, et al.
    Trop Biomed, 2014 Dec;31(4):633-40.
    PMID: 25776588 MyJurnal
    An accurate diagnosis for toxoplasmosis is crucial for pregnant women as this infection may lead to severe sequelae in the fetus. The value of IgG avidity assay as a tool to determine acute and chronic toxoplasmosis during pregnancy was evaluated in Universiti Kebangsaan Malaysia Medical Centre (UKMMC). In this study, 281 serum samples from 281 pregnant women in various trimesters were collected. These samples were assayed using specific anti-Toxoplasma IgM and IgG antibodies, followed by IgG avidity test. The overall seroprevalence of toxoplasmosis in pregnant women was 35.2% (33.5% for anti-Toxoplasma IgG and 1.8% for both anti-Toxoplasma IgG and IgM antibodies). Of 5 (1.8%) serum samples positive for IgM ELISA, 4 had high-avidity antibodies, suggesting past infection and one sample with borderline avidity index. Two samples with low avidity were from IgM negative serum samples. The IgG avidity assay exhibited an excellent specificity of 97.6% and a negative predictive value (NPV) of 95.6%. The study also demonstrated no significant correlation between avidity indexes of the sera with IgG (r=0.12, p=0.24) and IgM (r=-0.00, p=0.98), suggesting the complementary needs of the two tests for a better diagnosis outcome. These findings highlight the usefulness of IgG avidity assay in excluding a recently acquired toxoplasmosis infection in IgM-positive serum sample.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  4. Fulltext Seroprevalence of anti-Toxoplasma gondii IgG antibody in patients with schizophrenia
    Emelia O, Amal RN, Ruzanna ZZ, Shahida H, Azzubair Z, Tan KS, et al.
    Trop Biomed, 2012 Mar;29(1):151-9.
    PMID: 22543615 MyJurnal
    Schizophrenia is a pervasive neuropsychiatric disease of unknown cause. Previous studies have reported that toxoplasmosis may be a possible cause of schizophrenia. To ascertain possible relationship between Toxoplasma gondii and schizophrenia, a cross sectional study, employing an enzyme-linked immunosorbent assay (ELISA) was performed to study the seroprevalence of anti-T. gondii IgG antibody in schizophrenic patients. Furthermore, demographic data analysis from schizophrenic patients were analysed to associate toxoplasmosis with schizophrenia. A total of 288 serum samples from schizophrenic patients (n=144) and psychiatrically healthy volunteers (n=144) were recruited in this study. Interestingly, a significant result in the serointensity rate of anti-T. gondii IgG antibody (> 60 IU/mL) in schizophrenic patients (61.1%) was demonstrated as compared to psychiatrically healthy volunteers (40.8%) (X² = 4.236, p < 0.050). However, there was no significant difference between the seropositivity rate of anti-T. gondii IgG antibody between the two groups. Analysis from demographic data revealed that the seropositivity rate of anti-T. gondii IgG antibody in schizophrenic patients was significantly associated with age group of more than 40 years old (p=0.007) and between ethnic (p=0.046). Nevertheless, no significant association between seropositivity rate of anti-T. gondii IgG antibody with gender (p=0.897), duration of illness (p=0.344) and family history of schizophrenia (p=0.282) in these patients. Thus, this finding is essential as a preliminary data in Malaysia to establish the association between T. gondii and schizophrenia.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  5. Seroprevalence of low avidity anti-Toxoplasma IgG in pregnant women and its relationship with their age and contact with cats
    Khan K, Khan W, Khan T, Naaz G, Naheda A, Aqeel S
    Trop Biomed, 2020 Dec 01;37(4):1038-1049.
    PMID: 33612756 DOI: 10.47665/tb.37.4.1038
    Toxoplasma gondii is a protozoan parasite that can infect all mammals, serving as intermediate hosts. The cause of congenital toxoplasmosis is transplacental transmission of the parasite to the foetus, resulting in wide range of manifestations from mild chorioretinitis to miscarriage. Its frequency can be reduced by early screening of pregnant women which is based mainly on tests for anti-Toxoplasma antibodies. We collected serum samples of 594 pregnant women (subjects) after taking their consent over a period of two years (2016-2018) and analyzed them for anti-Toxoplasma IgG by ELISA. The positive samples were then analyzed for IgG avidity test which could differentiate between recent and past infections. The seroprevalence was also correlated with the age of the subjects and their contact with cats. 162 subjects were found positive out of which only three showed a recent infection. After following up until delivery, one of them delivered a baby who had jaundice and was diagnosed with anti-Toxoplasma IgM at birth. The foetus of the second subject died in-utero, while the third woman delivered a normal baby after being given spiramycin when diagnosed with toxoplasmosis in the first trimester. It was found that most of the positive subjects had frequent contact with cats. Invasion of the parasite during third trimester resulted in death in-utero and jaundice. Most common cause of pregnancy wastage during our study was spontaneous abortions while pregnancy loss due to congenital anomalies was rare.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  6. Isolation and genotyping of Toxoplasma gondii from free-range ducks in Malaysia
    Puvanesuaran VR, Noordin R, Balakrishnan V
    Avian Dis, 2013 Mar;57(1):128-32.
    PMID: 23678741
    Toxoplasma gondii is a parasitic protozoan that infects nearly one-third of humans. The present study was performed to isolate and genotype T. gondii from free-range ducks in Malaysia. Sera, heads, and hearts from 205 ducks were obtained from four states in Peninsular Malaysia, and 30 (14.63%) sera were found to be seropositive when assayed with the modified agglutination test (MAT > or = 1:6). All the positive samples were inoculated into mice, and T. gondii was successfully isolated from four individual duck samples (1.95%), which were initially found to be strongly seropositive (MAT > or = 1:24). The isolates were subjected to PCR-RFLP analysis, and two T. gondii strains were identified: type I and type II. This is the first reported study on the genetic characterization of T. gondii isolates from free-range farm animals in Southeast Asia.
    Matched MeSH terms: Antibodies, Protozoan/blood
  7. Fulltext Antibodies to Intercellular Adhesion Molecule 1-Binding Plasmodium falciparum Erythrocyte Membrane Protein 1-DBLβ Are Biomarkers of Protective Immunity to Malaria in a Cohort of Young Children from Papua New Guinea
    Tessema SK, Utama D, Chesnokov O, Hodder AN, Lin CS, Harrison GLA, et al.
    Infect Immun, 2018 08;86(8).
    PMID: 29784862 DOI: 10.1128/IAI.00485-17
    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) mediates parasite sequestration to the cerebral microvasculature via binding of DBLβ domains to intercellular adhesion molecule 1 (ICAM1) and is associated with severe cerebral malaria. In a cohort of 187 young children from Papua New Guinea (PNG), we examined baseline levels of antibody to the ICAM1-binding PfEMP1 domain, DBLβ3PF11_0521, in comparison to four control antigens, including NTS-DBLα and CIDR1 domains from another group A variant and a group B/C variant. Antibody levels for the group A antigens were strongly associated with age and exposure. Antibody responses to DBLβ3PF11_0521 were associated with a 37% reduced risk of high-density clinical malaria in the follow-up period (adjusted incidence risk ratio [aIRR] = 0.63 [95% confidence interval {CI}, 0.45 to 0.88; P = 0.007]) and a 25% reduction in risk of low-density clinical malaria (aIRR = 0.75 [95% CI, 0.55 to 1.01; P = 0.06]), while there was no such association for other variants. Children who experienced severe malaria also had significantly lower levels of antibody to DBLβ3PF11_0521 and the other group A domains than those that experienced nonsevere malaria. Furthermore, a subset of PNG DBLβ sequences had ICAM1-binding motifs, formed a distinct phylogenetic cluster, and were similar to sequences from other areas of endemicity. PfEMP1 variants associated with these DBLβ domains were enriched for DC4 and DC13 head structures implicated in endothelial protein C receptor (EPCR) binding and severe malaria, suggesting conservation of dual binding specificities. These results provide further support for the development of specific classes of PfEMP1 as vaccine candidates and as biomarkers for protective immunity against clinical P. falciparum malaria.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  8. Fulltext Induction and Kinetics of Complement-Fixing Antibodies Against Plasmodium vivax Merozoite Surface Protein 3α and Relationship With Immunoglobulin G Subclasses and Immunoglobulin M
    Oyong DA, Wilson DW, Barber BE, William T, Jiang J, Galinski MR, et al.
    J Infect Dis, 2019 11 06;220(12):1950-1961.
    PMID: 31419296 DOI: 10.1093/infdis/jiz407
    BACKGROUND: Complement-fixing antibodies are important mediators of protection against Plasmodium falciparum malaria. However, complement-fixing antibodies remain uncharacterized for Plasmodium vivax malaria. P. vivax merozoite surface protein 3α (PvMSP3α) is a target of acquired immunity and a potential vaccine candidate.

    METHODS: Plasma from children and adults with P. vivax malaria in Sabah, Malaysia, were collected during acute infection, 7 and 28 days after drug treatment. Complement-fixing antibodies and immunoglobulin M and G (IgM and IgG), targeting 3 distinctive regions of PvMSP3α, were measured by means of enzyme-linked immunosorbent assay.

    RESULTS: The seroprevalence of complement-fixing antibodies was highest against the PvMSP3α central region (77.6%). IgG1, IgG3, and IgM were significantly correlated with C1q fixation, and both purified IgG and IgM were capable of mediating C1q fixation to PvMSP3α. Complement-fixing antibody levels were similar between age groups, but IgM was predominant in children and IgG3 more prevalent in adults. Levels of functional antibodies increased after acute infection through 7 days after treatment but rapidly waned by day 28.

    CONCLUSION: Our study demonstrates that PvMSP3α antibodies acquired during P. vivax infection can mediate complement fixation and shows the important influence of age in shaping these specific antibody responses. Further studies are warranted to understand the role of these functional antibodies in protective immunity against P. vivax malaria.

    Matched MeSH terms: Antibodies, Protozoan/blood
  9. Fulltext Toxoplasma infection in pregnant women: a current status in Songklanagarind hospital, southern Thailand
    Andiappan H, Nissapatorn V, Sawangjaroen N, Chemoh W, Lau YL, Kumar T, et al.
    Parasit Vectors, 2014;7:239.
    PMID: 24886651 DOI: 10.1186/1756-3305-7-239
    Toxoplasmosis, being one of the TORCH's infections in pregnant women, is caused by Toxoplasma gondii, an obligate intracellular protozoan parasite. This parasitic infection in pregnancy congenitally causes severe outcomes to their fetus and newborn. This study aimed to determine the seroprevalence and stages of Toxoplasma infection in pregnant women and its associated risks exposures.
    Matched MeSH terms: Antibodies, Protozoan/blood
  10. Fulltext Exposure and infection to Plasmodium knowlesi in case study communities in Northern Sabah, Malaysia and Palawan, The Philippines
    Fornace KM, Herman LS, Abidin TR, Chua TH, Daim S, Lorenzo PJ, et al.
    PLoS Negl Trop Dis, 2018 Jun;12(6):e0006432.
    PMID: 29902171 DOI: 10.1371/journal.pntd.0006432
    BACKGROUND: Primarily impacting poor, rural populations, the zoonotic malaria Plasmodium knowlesi is now the main cause of human malaria within Malaysian Borneo. While data is increasingly available on symptomatic cases, little is known about community-level patterns of exposure and infection. Understanding the true burden of disease and associated risk factors within endemic communities is critical for informing evidence-based control measures.

    METHODOLOGY/PRINCIPAL FINDINGS: We conducted comprehensive surveys in three areas where P. knowlesi transmission is reported: Limbuak, Pulau Banggi and Matunggung, Kudat, Sabah, Malaysia and Bacungan, Palawan, the Philippines. Infection prevalence was low with parasites detected by PCR in only 0.2% (4/2503) of the population. P. knowlesi PkSERA3 ag1 antibody responses were detected in 7.1% (95% CI: 6.2-8.2%) of the population, compared with 16.1% (14.6-17.7%) and 12.6% (11.2-14.1%) for P. falciparum and P. vivax. Sero-prevalence was low in individuals <10 years old for P. falciparum and P. vivax consistent with decreased transmission of non-zoonotic malaria species. Results indicated marked heterogeneity in transmission intensity between sites and P. knowlesi exposure was associated with agricultural work (OR 1.63; 95% CI 1.07-2.48) and higher levels of forest cover (OR 2.40; 95% CI 1.29-4.46) and clearing (OR 2.14; 95% CI 1.35-3.40) around houses. Spatial patterns of P. knowlesi exposure differed from exposure to non-zoonotic malaria and P. knowlesi exposed individuals were younger on average than individuals exposed to non-zoonotic malaria.

    CONCLUSIONS/SIGNIFICANCE: This is the first study to describe serological exposure to P. knowlesi and associated risk factors within endemic communities. Results indicate community-level patterns of infection and exposure differ markedly from demographics of reported cases, with higher levels of exposure among women and children. Further work is needed to understand these variations in risk across a wider population and spatial scale.

    Matched MeSH terms: Antibodies, Protozoan/blood
  11. Fulltext Cloning, expression, and immunocharacterization of surface protein containing an altered thrombospondin repeat domain (SPATR) from Plasmodium knowlesi
    Palaeya V, Lau YL, Mahmud R, Chen Y, Fong MY
    Malar J, 2013;12:182.
    PMID: 23734702 DOI: 10.1186/1475-2875-12-182
    Plasmodium knowlesi is the fifth species identified to cause malaria in humans and is often misdiagnosed as Plasmodium malariae due to morphological similarities. The development of an inexpensive, serological detection method utilizing antibodies specific to P. knowlesi would be a valuable tool for diagnosis. However, the identification of specific antigens for these parasites remains a major challenge for generating such assays. In this study, surface protein containing an altered thrombospondin repeat domain (SPATR) was selected as a potentially specific antigen from P. knowlesi. Its multistage expression by sporozoites, asexual erythrocytic forms and gametocytes, along with its possible role in liver cell invasion, suggests that SPATR could be used as a biomarker for diagnosis of P. knowlesi.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  12. Immunogenic characterization of the chimeric surface antigen 1 and 2 (SAG1/2) of Toxoplasma gondii expressed in the yeast Pichia pastoris
    Lau YL, Thiruvengadam G, Lee WW, Fong MY
    Parasitol Res, 2011 Sep;109(3):871-8.
    PMID: 21455621 DOI: 10.1007/s00436-011-2315-6
    In this study, we successfully expressed a chimerical surface antigen 1 and 2 (SAG1/2) of Toxoplasma gondii in Pichia pastoris. Eighty human serum samples, including 60 from confirmed cases of toxoplasmosis, were tested against the purified recombinant SAG1/2 in Western blots. Results of Western blots targeted at Toxoplasma IgG and IgM showed that the recombinant SAG1/2 reacted with all sera from the toxoplasmosis cases but none with the Toxoplasma-negative serum samples. These results showed that the P. pastoris-derived recombinant SAG1/2 was sensitive and specific and suitable for use as antigen for detecting anti-Toxoplasma antibodies. To further investigate the immunological characteristic of the recombinant protein, the recombinant SAG1/2 was injected subcutaneously into BALB/c mice, and their serum was tested against total protein lysate of T. gondii. Mice immunized with the recombinant SAG1/2 reacted specifically with the native SAG1 and SAG2 of T. gondii. Significant proliferation of splenocytes stimulated with tachyzoite total protein lysate was observed in vaccinated BALB/c mice but not in those from negative control mice. Specific production of IFN-γ, the Th1-type cytokines, was also found in stimulated splenocytes from vaccinated mice. These results show that the chimeric protein recombinant SAG1/2 can elicit a Th1-associated protection against T. gondii infections in mice. Finally, vaccinated mice were significantly protected against lethal challenge with live T. gondii RH strain tachyzoites (P 
    Matched MeSH terms: Antibodies, Protozoan/blood
  13. Comparison of IgG-ELISA and IgG4-ELISA for Toxocara serodiagnosis
    Noordin R, Smith HV, Mohamad S, Maizels RM, Fong MY
    Acta Trop, 2005 Jan;93(1):57-62.
    PMID: 15589798
    Diagnosis of human toxocariasis, caused by Toxocara canis or Toxocara cati, normally relies on a combination of the presence of clinical signs and symptoms backed by positive serology. The use of Toxocara excretory-secretory antigen (TES) in ELISA assays increases the test specificity. However, in tropical countries where soil-transmitted helminths are endemic, cross-reactivity from antibodies to these intestinal parasites poses a significant limitation for Toxocara serodiagnosis. To increase the specificity of serodiagnosis, we compared the use of IgG-ELISA to the use of IgG4-ELISA using commercially manufactured TES-coated plates. The sensitivity of the IgG-ELISA was 97.1%, while that of the IgG4-ELISA was 45.7%; the specificities were 36.0 and 78.6%, respectively. The study shows that employing both assays can improve the serodiagnosis of toxocariasis. An IgG4 immunoassay would also be useful in the secondary screening of antigen clones in the effort to develop improved serological tests for toxocariasis.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  14. Fulltext Evaluation of codon optimized recombinant Plasmodium knowlesi merozoite surface protein-119 (pkMSP-119) expressed in Pichia pastoris
    Lau YL, Cheong FW, Chin LC, Mahmud R, Chen Y, Fong MY
    Trop Biomed, 2014 Dec;31(4):749-59.
    PMID: 25776601 MyJurnal
    Malaria causes high global mortality and morbidity annually. Plasmodium knowlesi has been recognised as the fifth human Plasmodium sp. and its infection is widely distributed in Southeast Asia. Merozoite surface protein-119 (MSP-119) appears as a potential candidate for malaria blood stage vaccine as it could induce protective immunity. In this study, codon optimized P. knowlesi MSP-119 (pkMSP-119) was expressed and purified in yeast Pichia pastoris expression system. The purified recombinant protein was further evaluated using Western blot assay using knowlesi malaria, non-knowlesi human malaria, non-malarial parasitic infections and healthy serum samples (n = 50). The sensitivity of purified pkMSP-119 towards detection of knowlesi infection was as 28.6% (2/7). pkMSP-119 did not react with all non-malarial parasitic infections and healthy donor sera, yet reacted with some non-knowlesi human malaria sera, therefore lead to a specificity of 86.0% (37/43).
    Matched MeSH terms: Antibodies, Protozoan/blood*
  15. Fulltext Characterisation of a truncated Toxoplasma gondii surface antigen 2 (SAG2) secreted by the methylotrophic yeast Pichia pastoris
    Lau YL, Shamilah H, Fong MY
    Trop Biomed, 2006 Dec;23(2):186-93.
    PMID: 17322821 MyJurnal
    A truncated form of surface antigen 2 (SAG2) of the protozoan parasite Toxoplasma gondii was cloned and expressed in the methylotrophic yeast Pichia pastoris. This recombinant antigen, designated as recSAG2-N, contained only the N-terminal half of the native SAG2. The recSAG2-N was secreted by the Pichia pastoris into the culture supernatant, and it was harvested by using the trichloroacetic acid precipitation method. Specificity of recSAG2-N was evaluated in western blot assays. Fifty human serum samples, including 32 from confirmed cases of toxoplasmosis, were tested. Results from the assays showed that recSAG2-N reacted with sera from the toxoplasmosis cases only. In vivo experiments showed that serum from mice which received recSAG2-N reacted with the native SAG2 of T. gondii.
    Matched MeSH terms: Antibodies, Protozoan/blood
  16. Seroepidemiological studies of bovine babesiosis caused by Babesia ovata, B. bigemina and B. bovis in Peninsular Malaysia
    Chandrawathani P, Tsuji N, Kawazu S, Ishikawa M, Fujisaki K
    J Vet Med Sci, 1994 Oct;56(5):929-32.
    PMID: 7865596
    Cattle in Peninsular Malaysia were examined for evidence of infection with Babesia ovata, B. bigemina and B. bovis by an enzyme-linked immunosorbent assay for detection of antibody to the three Babesia species. All of the test samples when assayed with B. ovata antigen, resulted in low value indicating low probability of cattle infected with B. bigemina, 74.4% were positive for B. bovis and 72.6% were positive for both Babesia species. In addition, a serological survey with regard to age difference was carried out on a milk production farm. High reactivity antibody to B. bigemina and B. bovis was detected in calves less than 1 month of the age. The reactivity decreased in calves 1-3 months of the age. Then, the reactivity increased for both Babesia species in 6 months old calves. These results suggested that cattle infected with B. bigemina and B. bovis were widespread throughout Peninsular Malaysia and that both parasites might exist as an enzootical parasite.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  17. IgG avidity Western blot using Toxoplasma gondii rGRA-7 cloned from nucleotides 39-711 for serodiagnosis of acute toxoplasmosis
    Deshpande PS, Kotresha D, Noordin R, Yunus MH, Saadatnia G, Golkar M, et al.
    Rev Inst Med Trop Sao Paulo, 2013 4 9;55(2):79-83.
    PMID: 23563759
    Toxoplasmosis is an important cause of congenital infection. The present study was performed to evaluate the usefulness of recombinant (r) GRA-7 cloned from nucleotides (n) 39-711 in discriminating between acute and chronic toxoplasmosis. First, commercial IgM, IgG and IgG avidity ELISAs were used to determine the serological profile of the sera. Serum samples were from 20 symptomatic patients with acute infection (low IgG avidity, IgM positive), 10 with chronic infection (high IgG avidity, IgM negative) and 10 with indeterminate IgG avidity (IgM positive) which were tested for IgG avidity status with an in-house developed IgG avidity Western blot using the rGRA-7 recombinant antigen. All 20 sera from cases of probable acute infection showed bands which either faded out completely or reduced significantly in intensity after treatment with 8 M urea, whereas the band intensities of the 10 serum samples from chronic cases remained the same. Of the 10 sera with indeterminate IgG avidity status, after treatment with 8 M urea the band intensities with six sera remained the same, two sera had completely faded bands and another two sera had significantly reduced band intensities. Discrimination between acute and chronic toxoplasmosis was successfully performed by the in-house IgG avidity Western blot.
    Matched MeSH terms: Antibodies, Protozoan/blood*
  18. Fulltext Evaluation of Entamoeba histolytica recombinant phosphoglucomutase protein for serodiagnosis of amoebic liver abscess
    Ning TZ, Kin WW, Noordin R, Cun ST, Chong FP, Mohamed Z, et al.
    BMC Infect Dis, 2013;13:144.
    PMID: 23514636 DOI: 10.1186/1471-2334-13-144
    Amoebic liver abscess (ALA) is the most frequent clinical presentation of extra-intestinal amoebiasis. The diagnosis of ALA is typically based on the developing clinical symptoms, characteristic changes on radiological imaging and serology. Numerous serological tests have been introduced for the diagnosis of ALA, either detecting circulating amoebic antigens or antibodies. However those tests show some pitfalls in their efficacy and/or the preparation of the tests are costly and tedious. The commercial IHA kit that used crude antigen was reported to be useful in diagnosis of ALA, however high antibody background in endemic areas may cause problems in its interpretation. Thus, discovery of well-defined antigen(s) is urgently needed to improve the weaknesses of current serodiagnostic tests.
    Matched MeSH terms: Antibodies, Protozoan/blood
  19. Fulltext Cloning and expression of Toxoplasma gondii dense granular protein 4 (GRA4) in Pichia pastoris
    Lau YL, Hasan MT, Thiruvengadam G, Idris MM, Init I
    Trop Biomed, 2010 Dec;27(3):525-33.
    PMID: 21399595
    GRA4 of Toxoplasma gondii has been shown to prompt IgG, IgM and IgA responses in previous studies and is thus considered one of the major immunogenic proteins from T. gondii that can be used for both diagnostics purposes and vaccine development. This study seeks to clone and express the GRA4 in Pichia pastoris, which has numerous advantages over other systems for expression of eukaryotic proteins. In order to achieve this, the gene was cloned into the pPICZα A expression vector, which was then incorporated into the P. pastoris genome via insertional integration for expression of the recombinant protein, under the AOX1 promoter. The antigen was expressed along with the prepro sequence of the α-factor of yeast so that it could be excreted out of the P. pastoris cells and obtained from the medium. Upon SDS-PAGE analysis it was found that the recombinant protein was expressed optimally as a 40 kDa protein after 96 hours of induction with 0.75% of methanol. The expressed GRA4 protein showed discrepancy in size with the calculated molecular mass. This may be attributed to the various posttranslational modifications including glycosylation and phosphorylation. Despite the difference in molecular weight, the recombinant protein was able to detect toxoplasmosis in Western blot format. The recombinant GRA4 was expressed with an intact polyhistidine-tag, which could be used for future purification of the antigen.
    Matched MeSH terms: Antibodies, Protozoan/blood
  20. Fulltext Serological measures to assess the efficacy of malaria control programme on Ambae Island, Vanuatu
    Idris ZM, Chan CW, Mohammed M, Kalkoa M, Taleo G, Junker K, et al.
    Parasit Vectors, 2017 Apr 26;10(1):204.
    PMID: 28441959 DOI: 10.1186/s13071-017-2139-z
    BACKGROUND: Seroepidemiology can provide evidence for temporal changes in malaria transmission and is an important tool to evaluate the effectiveness of control interventions. During the early 2000s, Vanuatu experienced an acute increase in malaria incidence due to a lapse in funding for vector control. After the distribution of subsidised insecticide-treated nets (ITNs) resumed in 2003, malaria incidence decreased in the subsequent years. This study was conducted to find the serological evidence supporting the impact of ITN on exposure to Anopheles vector bites and parasite prevalence.

    METHODS: On Ambae Island, blood samples were collected from 231 and 282 individuals in 2003 and 2007, respectively. Parasite prevalence was determined by microscopy. Antibodies to three Plasmodium falciparum (PfSE, PfMSP-119, and PfAMA-1) and three Plasmodium vivax (PvSE, PvMSP-119, and PvAMA-1) antigens, as well as the Anopheles-specific salivary antigen gSG6, were detected by ELISA. Age-specific seroprevalence was analysed using a reverse catalytic modelling approach to estimate seroconversion rates (SCRs).

    RESULTS: Parasite rate decreased significantly (P 

    Matched MeSH terms: Antibodies, Protozoan/blood
Related Terms
Filters
Contact Us

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

External Links