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Yai LE, Ragozo AM, Soares RM, Pena HF, Su C, Gennari SM. Genetic diversity among capybara (Hydrochaeris hydrochaeris) isolates of Toxoplasma gondii from Brazil. Vet Parasitol 2009; 162:332-7. [DOI: 10.1016/j.vetpar.2009.03.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 02/05/2009] [Accepted: 03/02/2009] [Indexed: 10/21/2022]
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Su C, Ma L, Wang R, Hu X, Chen S, Shao L, Wu H, Shen L, Zhang Z, Wu G. [Studies on immunoprotection in mice after immunization with Schistosoma japonicum 22.6 kDa recombinant protein]. ZHONGGUO JI SHENG CHONG XUE YU JI SHENG CHONG BING ZA ZHI = CHINESE JOURNAL OF PARASITOLOGY & PARASITIC DISEASES 2009; 17:288-91. [PMID: 12563860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To evaluate the immunoprotective effect of Schistosoma japonicum recombinant 22.6 kDa (rSj22.6) and Sj22.6/Sj26 GST fusion protein. METHODS The Sj22.6/Sj26 GST fusion protein was prepared by affinity chromatography using glutathione Sepharose 4B. The purified rSj22.6 could be cleaved easily from the fusion protein with Thrombin. 17 and 12 mice immunized with rSj22.6 and Sj22.6/Sj26 GST separately were each challenged with 40 +/- 1 S. japonicum cercariae. RESULTS In BALB/c mice, the rSj22.6 and Sj22.6/Sj26 GST could induce 32.1 (P < 0.005) and 34.9% (P < 0.02) worm reduction, respectively, as well as 28.4% (P < 0.02) and 45.1% (P < 0.005) total egg reduction, respectively. CONCLUSION Bpth rSj22.6 and Sj22.6/Sj26 GST fusion protein are partially effective against S. japonicum.
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Dubey JP, Mergl J, Gehring E, Sundar N, Velmurugan GV, Kwok OCH, Grigg ME, Su C, Martineau D. Toxoplasmosis in captive dolphins (Tursiops truncatus) and walrus (Odobenus rosmarus). J Parasitol 2009; 95:82-5. [PMID: 19245284 DOI: 10.1645/ge-1764.1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Accepted: 07/08/2008] [Indexed: 11/10/2022] Open
Abstract
Toxoplasma gondii infection in marine mammals is intriguing and indicative of contamination of the ocean environment and coastal waters with oocysts. Toxoplasma gondii infection was detected in captive marine mammals at a sea aquarium in Canada. Antibodies to T. gondii were found in all 7 bottlenose dolphins (Tursiops truncatus) tested. Two of these dolphins, as well as a walrus (Odobenus rosmarus) at the facility, died. Encephalitis and T. gondii tissue cysts were identified in histological sections of the brain of 1 dolphin (dolphin no. 1). Another dolphin (dolphin no. 2) had mild focal encephalitis without visible organisms, but viable T. gondii was isolated by bioassay in mice and cats from its brain and skeletal muscle; this strain was designated TgDoCA1. The PCR-RFLP typing using 11 markers (B1, SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) identified a Type II strain. The DNA sequencing of B1 and SAG1 alleles amplified from TgDoCA1 and directly from the brains of dolphin no. 1 and the walrus showed archetypal alleles consistent with infection by a Type II strain. No unique polymorphisms were detected. This is apparently the first report of isolation of T. gondii from a marine mammal in Canada.
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Dubey JP, Velmurugan GV, Morales JA, Arguedas R, Su C. Isolation of Toxoplasma gondii from the Keel-Billed Toucan (Ramphastos sulfuratus) From Costa Rica. J Parasitol 2009; 95:467-8. [DOI: 10.1645/ge-1846.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Accepted: 10/02/2008] [Indexed: 11/10/2022] Open
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Velmurugan GV, Su C, Dubey JP. Isolate Designation and Characterization of Toxoplasma gondii Isolates From Pigs in the United States. J Parasitol 2009; 95:95-9. [DOI: 10.1645/ge-1746.1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 07/09/2008] [Indexed: 11/10/2022] Open
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Wang JM, Su C, Wang Y, Huang YJ, Yang Z, Chen L, Wu F, Xu SY, Tao J. Elevated circulating endothelial microparticles and brachial-ankle pulse wave velocity in well-controlled hypertensive patients. J Hum Hypertens 2008; 23:307-15. [PMID: 19037229 DOI: 10.1038/jhh.2008.137] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Vascular dysfunction in hypertensive condition is characterized by impaired endothelial function and reduced artery elasticity. Circulating endothelial microparticles (EMPs) and brachial-ankle pulse wave velocity (baPWV) are novel evaluation parameters for vascular function. However, their changes in patients with well-controlled blood pressure (BP) have not been fully acquired. To address this issue, circulating EMPs, defined as CD31+/CD42- MPs and baPWV were detected in 30 healthy subjects, 30 uncontrolled hypertensive (UCHT) patients and 23 well-controlled hypertensive (WCHT) patients. UCHT patients displayed elevated baPWV (P<0.01) and circulating EMPs (P<0.01) compared with healthy subjects. In WCHT patients, vascular damage represented by these two parameters constantly existed (P<0.01). Values of circulating EMPs were positively related to baPWV (P<0.01). Multivariate regression defined circulating EMPs as an independent contributor to the increase of baPWV value (P<0.05). Our study indicated that though BP was controlled, impaired endothelial function and arterial elasticity continued. The optimal therapy for patients with hypertension should include not only lowering BP but also improvement of vascular injury in parallel.
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Dubey JP, Fair PA, Sundar N, Velmurugan G, Kwok OCH, McFee WE, Majumdar D, Su C. Isolation of Toxoplasma gondii from bottlenose dolphins (Tursiops truncatus). J Parasitol 2008; 94:821-3. [PMID: 18576793 DOI: 10.1645/ge-1444.1] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Accepted: 11/05/2007] [Indexed: 11/10/2022] Open
Abstract
Toxoplasma gondii infection in marine mammals is intriguing and indicative of contamination of the ocean environment and coastal waters with oocysts. In previous serological surveys, >90% of bottlenose dolphins (Tursiops truncatus) from the coasts of Florida, South Carolina, and California had antibodies to T. gondii by the modified agglutination test (MAT). In the present study, attempts were made to isolate T. gondii from dead T. truncatus. During 2005, 2006, and 2007, serum or blood clot, and tissues (brain, heart, skeletal muscle) of 52 T. truncatus stranded on the coasts of South Carolina were tested for T. gondii. Antibodies to T. gondii (MAT 1:25 or higher) were found in 26 (53%) of 49 dolphins; serum was not available from 3 animals. Tissues (heart, muscle, and sometimes brain) of 32 dolphins (26 seropositive, 3 seronegative, and 3 without accompanying sera) were bioassayed for T. gondii in mice, or cats, or both. Tissues of the recipient mice were examined for T. gondii stages. Feces of recipient cats were examined for shedding of T. gondii oocysts, but none excreted oocysts. Toxoplasma gondii was isolated from hearts of the 3 dolphins (2 with MAT titers of 1:200, and 1 without accompanied serum) by bioassay in mice. Genotyping of these 3 T. gondii isolates (designated TgDoUs1-3) with the use of 10 PCR-RFLP markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) revealed 2 genotypes. Two of the 3 isolates have Type II alleles at all loci and belong to the clonal Type II lineage. One isolate has a unique genotype. This is the first report of isolation of viable T. gondii from T. truncatus.
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Pascua M, Su C, Lewis JD, Brensinger C, Lichtenstein GR. Meta-analysis: factors predicting post-operative recurrence with placebo therapy in patients with Crohn's disease. Aliment Pharmacol Ther 2008; 28:545-56. [PMID: 18565159 DOI: 10.1111/j.1365-2036.2008.03774.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND The use of placebo in randomized clinical trials (PC-RCTs) is often required to evaluate drug efficacy in maintenance of Crohn's disease (CD). AIM To determine pooled estimates of placebo rates of maintaining clinical remission and endoscopic recurrence following surgery for CD and identify factors that influenced placebo outcomes. METHODS We performed a systematic review and meta-analysis of PC-RCTs evaluating post-operative maintenance therapies for CD identified from MEDLINE from 1966 to 2005. RESULTS Twelve studies met our inclusion criteria. The pooled placebo rate of maintaining clinical remission was 56% (95% CI 47-64%; range 34-89%) during a median follow-up of 52 weeks (range 12-156 weeks), but significant heterogeneity existed among the studies (P < 0.001). Prior steroid therapy was the only factor found to be associated with maintaining remission (P = 0.04). The pooled placebo endoscopic recurrence rate was 58% (95% CI 51-65%; range 36-80%) during a median follow-up of 52 weeks (range 12-156 weeks), with significant heterogeneity noted (P = 0.0003). Prior surgery, concomitant small bowel and colonic disease, fistulizing phenotype, or prior immunomodulator therapy influenced endoscopic recurrence (P < 0.05). CONCLUSION Placebo rates in PC-RCTs evaluating post-operative clinical and endoscopic recurrence demonstrate significant variability, which is influenced by specific study characteristics.
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Dubey JP, Velmurugan GV, Chockalingam A, Pena HFJ, de Oliveira LN, Leifer CA, Gennari SM, Bahia Oliveira LMG, Su C. Genetic diversity of Toxoplasma gondii isolates from chickens from Brazil. Vet Parasitol 2008; 157:299-305. [PMID: 18804329 DOI: 10.1016/j.vetpar.2008.07.036] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2008] [Revised: 07/28/2008] [Accepted: 07/29/2008] [Indexed: 10/21/2022]
Abstract
Until recently, Toxoplasma gondii was considered clonal with very little genetic variability. Recent studies indicate that T. gondii isolates from Brazil are genetically and biologically different from T. gondii isolates from USA and Europe. In the present study, we retyped 151 free range chicken isolates from Brazil including 117 newly isolated samples from 11 geographically areas (Alagoas, Bahia, Ceará, Maranhão, Paraná, Pernambuco, Rio de Janeiro, Rio Grande do Norte, São Paulo, Sergipe, and Rondonia) and 34 previously reported isolates from the very north (Pará) and the very south (Rio Grande do Sul). Ten PCR-RFLP markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico were used to genotype all isolates. Overall analysis of 151 T. gondii isolates revealed 58 genotypes. Half (29/58) of these genotypes had single isolate and the other half of the genotypes were characterized with two or more isolates. Only 1 of 151 isolates was clonal Type I strain and 5 were clonal Type III strains. Two isolates had mixed infections. Clonal Type II strain was absent. One strain was Type II at all loci, except BTUB. The results confirm high genetic diversity of T. gondii isolates from Brazil.
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Fan H, Su C, Wang Y, Yao J, Zhao K, Wang Y, Wang G. Sedimentary arsenite-oxidizing and arsenate-reducing bacteria associated with high arsenic groundwater from Shanyin, Northwestern China. J Appl Microbiol 2008; 105:529-39. [DOI: 10.1111/j.1365-2672.2008.03790.x] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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161
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Dubey J, Velmurugan G, Ulrich V, Gill J, Carstensen M, Sundar N, Kwok O, Thulliez P, Majumdar D, Su C. Transplacental toxoplasmosis in naturally-infected white-tailed deer: Isolation and genetic characterisation of Toxoplasma gondii from foetuses of different gestational ages. Int J Parasitol 2008; 38:1057-63. [DOI: 10.1016/j.ijpara.2007.11.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2007] [Revised: 11/07/2007] [Accepted: 11/13/2007] [Indexed: 11/29/2022]
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Thomas J, Wang W, Yan N, Su C, Lynn R, Stambler N, Israel R. Analysis of response to methylnaltrexone by response to previous dose in advanced illness patients with opioid-induced constipation. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.9626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Velmurugan GV, Dubey JP, Su C. Genotyping studies of Toxoplasma gondii isolates from Africa revealed that the archetypal clonal lineages predominate as in North America and Europe. Vet Parasitol 2008; 155:314-8. [PMID: 18583059 DOI: 10.1016/j.vetpar.2008.04.021] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2008] [Revised: 04/17/2008] [Accepted: 04/21/2008] [Indexed: 10/22/2022]
Abstract
Until recently, Toxoplasma gondii was considered to be clonal with very little genetic variability. Recent studies indicate that T. gondii isolates from Brazil are genetically and biologically different from T. gondii isolates from USA and Europe. However, little is known of the genetics of T. gondii strains from Africa. In this study, we genotyped 19 T. gondii isolates from chickens from six African countries (Egypt, Kenya, Nigeria, Congo, Mali, and Burkina Fasco) using 10 PCR-RFLP markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The results revealed four genotypes. Thirteen isolates belong to the Type III lineage, five isolates have Type II alleles at all loci except apico and they belong to the Type II lineage. One isolate from Nigeria had atypical genotype. In general, these isolates were mostly clonal Type III and II strains that predominate in North American and European. DNA sequencing at several loci for representative isolates confirmed the results of PCR-RFLP genotyping. Taken together with recent studies of T. gondii isolates from Africa, it is clear that the three clonal lineages (Types I, II and III) predominate not only in North America and Europe, but also in Africa.
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Dubey JP, Hill DE, Sundar N, Velmurugan GV, Bandini LA, Kwok OCH, Pierce V, Kelly K, Dulin M, Thulliez P, Iwueke C, Su C. Endemic toxoplasmosis in pigs on a farm in Maryland: isolation and genetic characterization of Toxoplasma gondii. J Parasitol 2008; 94:36-41. [PMID: 18372619 DOI: 10.1645/ge-1312.1] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The prevalence of Toxoplasma gondii was investigated on a poorly managed pig farm in Maryland. Serum and tissue samples from 48 of the 100 pigs on the farm were available for T. gondii evaluation. Serological testing was performed using both ELISA and the modified agglutination test (MAT). Antibodies to T. gondii were detected by ELISA in 12 of 48 animals, while antibodies were detected in 34 of 48 pigs by MAT with titers of 1:10 in 1, 1:20 in 4, 1:40 in 7, 1:80 in 3, 1:160 in 8, 1:320 in 3, 1:640 in 4, and 1:1,280 in 4. Hearts of 16 pigs with MAT titers of 1:10 or higher were bioassayed for T. gondii in cats; 11 cats shed T. gondii oocysts. Hearts of 22 pigs were autolyzed and bioassayed only in mice; T. gondii was isolated from 3 of these 22 pigs. Genetic typing of the 14 T. gondii isolates using the SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico loci revealed 4 genotypes; 10 isolates belonged to type II lineage (genotypes 1 and 2), 3 belonged to genotype 3, and 1 belonged to genotype 4. Genotype 1 and 2 have type II alleles at all genetic loci, except the former has type II allele and the latter has a type I allele at locus Apico. Both genotypes 1 and 2 are considered to belong to the clonal type II lineages. Genotype 3 and 4 are nonclonal isolates. Results document high prevalence of T. gondii in pigs on a farm in Maryland.
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Dubey JP, Quirk T, Pittt JA, Sundar N, Velmurugan GV, Kwok OCH, Leclair D, Hill R, Su C. Isolation and genetic characterization of Toxoplasma gondii from raccoons (Procyon lotor), cats (Felis domesticus), striped skunk (Mephitis mephitis), black bear (Ursus americanus), and cougar (Puma concolor) from Canada. J Parasitol 2008; 94:42-5. [PMID: 18372620 DOI: 10.1645/ge-1349.1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Viable Toxoplasma gondii was isolated by bioassay in mice from tissues of 2 feral cats (Felis domesticus), 2 raccoons (Procyon lotor), a skunk (Mephitis mephitis) trapped in remote locations in Manitoba, Canada, and a black bear (Ursus americanus) from Kuujjuaq, northern Quebec, Canada. Genotyping of these T. gondii isolates using polymorphisms at 10 nuclear markers including SAGI, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast marker Apico revealed 4 genotypes. None of the isolates was clonal archetypal Types I, II, and III found in the United States. These results are in contrast with the Type II genotype that is widespread in domestic animals and humans throughout the United States and Europe. This is the first genotyping of T. gondii isolates from this part of North America.
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Dubey JP, López-Torres HY, Sundar N, Velmurugan GV, Ajzenberg D, Kwok OCH, Hill R, Dardé ML, Su C. Mouse-virulent Toxoplasma gondii isolated from feral cats on Mona Island, Puerto Rico. J Parasitol 2008; 93:1365-9. [PMID: 18314681 DOI: 10.1645/ge-1409.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Cats are essential in the life cycle of Toxoplasma gondii because they are the only hosts that can excrete the environmentally resistant oocysts. Samples of serum, feces, and tissues from cats from Mona, a remote island off the coast of Puerto Rico, were examined for T. gondii infection. Antibodies to T. gondii were assayed by the modified agglutination test and found in 16 of 19 (84.2%) of cats, with titers of 1:10 in 2, 1:80 in 1, 1:160 in 4, 1:320 in 3, and 1:1,280 or higher in 6. Tissues of 19 of the 20 cats were bioassayed in mice for T. gondii infection. Toxoplasma gondii was isolated from tissues of 12 cats: from the hearts of 9, skeletal muscle of 10, and brain of 1 cat. All infected mice from 10 of 12 isolates died of acute toxoplasmosis during primary infection. Genotyping of these 12 T. gondii isolates (designated (TgCatPr 1-12) by 10 multilocus PCR-RFLP markers, i.e., SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast marker Apico, and the 6 multilocus microsatellite markers TUB2, W35, TgM-A, B18, B17, and M33, revealed 7 genotypes; 5 isolates had Type I alleles at all loci except at 1 microsatellite locus, and the remainder were atypical. The latter isolates of T. gondii were different biologically and phenotypically from the feline isolates from the rest of the Americas. One isolate (TgCatPr 12) was a mixed infection with 2 genotypes.
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Dubey JP, Sundar N, Nolden CA, Samuel MD, Velmurugan GV, Bandini LA, Kwok OCH, Bodenstein B, Su C. Characterization of Toxoplasma gondii from raccoons (Procyon lotor), coyotes (Canis latrans), and striped skunks (Mephitis mephitis) in Wisconsin identified several atypical genotypes. J Parasitol 2008; 93:1524-7. [PMID: 18314705 DOI: 10.1645/ge-1245.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
During 2005-2006, sera and tissues from raccoons (Procyon lotor), coyotes (Canis latrans), and skunks (Mephitis mephitis) from the state of Wisconsin were tested for Toxoplasma gondii infection. Antibodies to T. gondii were found in 32 of 54 (59.2%) raccoons, 18 of 35 (51.4%) coyotes, and 5 of 7 (71.4%) skunks using the modified agglutination test and a cut-off titer of 1:20. Pooled tissues (brains, hearts, and tongues) from 30 raccoons, 15 coyotes, and 1 skunk were bioassayed for T. gondii infection in mice or cats. Viable T. gondii was isolated from 5 of 30 (16.7%) raccoons, 6 of 15 (40.0%) coyotes, and the skunk. Genetic characterization of the 12 parasite isolates by multilocus PCR-RFLP markers revealed 6 different genotypes including 5 atypical and I archetypal II lineages. The results indicate the prevalence of T. gondii in wildlife mammals is high and that these animals may serve as an important reservoir for transmission of T. gondii.
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Dubey JP, Huong LTT, Lawson BWL, Subekti DT, Tassi P, Cabaj W, Sundar N, Velmurugan GV, Kwok OCH, Su C. Seroprevalence and Isolation of Toxoplasma gondii from Free-Range Chickens in Ghana, Indonesia, Italy, Poland, and Vietnam. J Parasitol 2008; 94:68-71. [DOI: 10.1645/ge-1362.1] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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169
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Dubey JP, Sundar N, Hill D, Velmurugan GV, Bandini LA, Kwok OCH, Majumdar D, Su C. High prevalence and abundant atypical genotypes of Toxoplasma gondii isolated from lambs destined for human consumption in the USA. Int J Parasitol 2007; 38:999-1006. [PMID: 18191859 DOI: 10.1016/j.ijpara.2007.11.012] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 11/26/2007] [Accepted: 11/27/2007] [Indexed: 11/29/2022]
Abstract
Little information is available on the presence of viable Toxoplasma gondii in tissues of lambs worldwide. The prevalence of T. gondii was determined in 383 lambs (<1 year old) from Maryland, Virginia and West Virginia, USA. Hearts of 383 lambs were obtained from a slaughter house on the day of killing. Blood removed from each heart was tested for antibodies to T. gondii by using the modified agglutination test (MAT). Sera were first screened using 1:25, 1:50, 1: 100 and 1:200 dilutions, and hearts were selected for bioassay for T. gondii. Antibodies (MAT, 1:25 or higher) to T. gondii were found in 104 (27.1%) of 383 lambs. Hearts of 68 seropositive lambs were used for isolation of viable T. gondii by bioassay in cats, mice or both. For bioassays in cats, the entire myocardium or 500g was chopped and fed to cats, one cat per heart and faeces of the recipient cats were examined for shedding of T. gondii oocysts. For bioassays in mice, 50g of the myocardium was digested in an acid pepsin solution and the digest inoculated into mice; the recipient mice were examined for T. gondii infection. In total, 53 isolates of T. gondii were obtained from 68 seropositive lambs. Genotyping of the 53 T. gondii isolates using 10 PCR-restriction fragment length polymorphism markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico) revealed 57 strains with 15 genotypes. Four lambs had infections with two T. gondii genotypes. Twenty-six (45.6%) strains belong to the clonal Type II lineage (these strains can be further divided into two groups based on alleles at locus Apico). Eight (15.7%) strains belong to the Type III lineage. The remaining 22 strains were divided into 11 atypical genotypes. These results indicate high parasite prevalence and high genetic diversity of T. gondii in lambs, which has important implications in public health. We believe this is the first in-depth genetic analysis of T. gondii isolates from sheep in the USA.
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Wu HC, Tsai CS, Chou LW, Lee YR, Jiang JC, Su C, Lin JC. A scanning tunneling microscopy study of distyrylbenzene on Ag/Ge(111)-(sqr rt of 3 x sqr rt of 3)R30 degrees. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:12521-12528. [PMID: 17973407 DOI: 10.1021/la701845p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The adsorption and self-organized monolayers of trans,trans-distyrylbenzene (tt-DSB) and cis,cis-distyrylbenzene (cc-DSB) on Ag/Ge(111)-(sqr rt of 3 x sqr rt of 3)R30 degrees (Ag/Ge(111)-sqr rt of 3) were studied by low-temperature scanning tunneling microscopy (STM) in ultrahigh vacuum. tt-DSB and cc-DSB overlayers were prepared by vapor deposition at a substrate temperature of 200 K and imaged after the samples were cooled to 100 K. High-resolution images allow identification of the internal structure of individual tt-DSB molecules with three phenyl rings and their molecular arrangements on the Ag/Ge(111)-sqr rt of 3 surface. It is found that the intermolecular distance between two terminal phenyl rings in tt-DSB is about twice the lattice constant of Ag/Ge(111)-sqr rt of 3. Such a lattice match makes Ag/Ge(111)-sqr rt of 3 an ideal substrate for tt-DSB self-organization and the formation of a (3 x 1) overlayer unit cell. The structural model and the molecule registry corresponding to STM images for the adlayers of tt-DSB on Ag/Ge(111)-sqr rt of 3 are proposed and discussed. For cc-DSB adsorption on Ag/Ge(111)-sqr rt of 3, uniform molecular overlayers with two discernible molecular images corresponding to two major types of cc-DSB conformers were observed. The coexistence of multiple conformers and the mismatch of molecular dimension of cc-DSB with the substrate unit cell length limit the growth of large cc-DSB domains.
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Prestrud KW, Dubey JP, Asbakk K, Fuglei E, Su C. First isolate of Toxoplasma gondii from arctic fox (Vulpes lagopus) from Svalbard. Vet Parasitol 2007; 151:110-4. [PMID: 18096319 DOI: 10.1016/j.vetpar.2007.11.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 11/06/2007] [Accepted: 11/08/2007] [Indexed: 11/17/2022]
Abstract
Cats are considered essential for the maintenance of Toxoplasma gondii in nature. However, T. gondii infection has been reported in arctic fox (Vulpes lagopus) from the Svalbard high arctic archipelago where felids are virtually absent. To identify the potential source of T. gondii, we attempted to isolate and genetically characterize the parasite from arctic foxes in Svalbard. Eleven foxes were trapped live in Grumant (78 degrees 11'N, 15 degrees 09'E), Svalbard, in September 2005 and 2006. One of the foxes was found to be seropositive to T. gondii by the modified agglutination test (MAT). The fox was euthanized and its heart and brain were bioassayed in mice for the isolation of T. gondii. All 10 mice inoculated with brain tissue and one of the five inoculated with heart developed MAT antibodies, and tissue cysts were found in the brains of seropositive mice. Two cats fed tissues from infected mice shed T. gondii oocysts. Genotyping using 10 PCR-RFLP markers and DNA sequencing of gene loci BSR4, GRA6, UPRT1 and UPRT2 determined the isolate to be Type II strain, the predominant T. gondii lineage in the world.
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Sundar N, Cole RA, Thomas NJ, Majumdar D, Dubey JP, Su C. Genetic diversity among sea otter isolates of Toxoplasma gondii. Vet Parasitol 2007; 151:125-32. [PMID: 18155841 DOI: 10.1016/j.vetpar.2007.11.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Revised: 11/07/2007] [Accepted: 11/07/2007] [Indexed: 10/22/2022]
Abstract
Sea otters (Enhydra lutris) have been reported to become infected with Toxoplasma gondii and at times succumb to clinical disease. Here, we determined genotypes of 39 T. gondii isolates from 37 sea otters in two geographically distant locations (25 from California and 12 from Washington). Six genotypes were identified using 10 PCR-RFLP genetic markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico, and by DNA sequencing of loci SAG1 and GRA6 in 13 isolates. Of these 39 isolates, 13 (33%) were clonal Type II which can be further divided into two groups at the locus Apico. Two of the 39 isolates had Type II alleles at all loci except a Type I allele at locus L358. One isolate had Type II alleles at all loci except the Type I alleles at loci L358 and Apico. One isolate had Type III alleles at all loci except Type II alleles at SAG2 and Apico. Two sea otter isolates had a mixed infection. Twenty-one (54%) isolates had an unique allele at SAG1 locus. Further genotyping or DNA sequence analysis for 18 of these 21 isolates at loci SAG1 and GRA6 revealed that there were two different genotypes, including the previously identified Type X (four isolates) and a new genotype named Type A (14 isolates). The results from this study suggest that the sea otter isolates are genetically diverse.
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Pena HFJ, Gennari SM, Dubey JP, Su C. Population structure and mouse-virulence of Toxoplasma gondii in Brazil. Int J Parasitol 2007; 38:561-9. [PMID: 17963770 DOI: 10.1016/j.ijpara.2007.09.004] [Citation(s) in RCA: 263] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Revised: 09/03/2007] [Accepted: 09/06/2007] [Indexed: 11/17/2022]
Abstract
Recent studies found that isolates of Toxoplasma gondii from Brazil were biologically and genetically different from those in North America and Europe. However, to date only a small number of isolates have been analysed from different animal hosts in Brazil. In the present study DNA samples of 46 T. gondii isolates from cats in 11 counties in São Paulo state, Brazil were genetically characterised using 10 PCR restriction fragment length polymorphism markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico. An additional marker, CS3, that locates on chromosome VIIa and has previously been shown to be linked to acute virulence of T. gondii was also used to determine its association to virulence in mice. Genotyping of these 46 isolates revealed a high genetic diversity with 20 genotypes but no clonal Type I, II or III lineage was found. Two of the 46 isolates showed mixed infections. Combining genotyping data in this study with recent reported results from chickens, dogs and cats in Brazil (total 125 isolates) identified 48 genotypes and 26 of these genotypes had single isolates. Four of the 48 genotypes with multiple isolates identified from different hosts and locations are considered the common clonal lineages in Brazil. These lineages are designated as Types BrI, BrII, BrIII and BrIV. These results indicate that the T. gondii population in Brazil is highly diverse with a few successful clonal lineages expanded into wide geographical areas. In contrast to North America and Europe, where the Type II clonal lineage is overwhelmingly predominant, no Type II strain was identified from the 125 Brazil isolates. Analysis of mortality rates in infected mice indicates that Type BrI is highly virulent, Type BrIII is non-virulent, whilst Type BrII and BrIV lineages are intermediately virulent. In addition, allele types at the CS3 locus are strongly linked to mouse-virulence of the parasite. Thus, T. gondii has an epidemic population structure in Brazil and the major lineages have different biological traits.
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Khan A, Fux B, Su C, Dubey JP, Darde ML, Ajioka JW, Rosenthal BM, Sibley LD. Recent transcontinental sweep of Toxoplasma gondii driven by a single monomorphic chromosome. Proc Natl Acad Sci U S A 2007; 104:14872-7. [PMID: 17804804 PMCID: PMC1965483 DOI: 10.1073/pnas.0702356104] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Toxoplasma gondii is a highly prevalent protozoan parasite that infects a wide range of animals and threatens human health by contaminating food and water. A markedly limited number of clonal parasite lineages have been recognized as predominating in North American and European populations, whereas strains from South America are comparatively diverse. Here, we show that strains from North America and Europe share distinct genetic polymorphisms that are mutually exclusive from polymorphisms in strains from the south. A striking exception to this geographic segregation is a monomorphic version of one chromosome (Chr1a) that characterizes virtually all northern and many southern isolates. Using a combination of molecular phylogenetic and phenotypic analyses, we conclude that northern and southern parasite populations diverged from a common ancestor in isolation over a period of approximately 10(6) yr, and that the monomorphic Chr1a has swept each population within the past 10,000 years. Like its definitive feline hosts, T. gondii may have entered South America and diversified there after reestablishment of the Panamanian land bridge. Since then, recombination has been an infrequent but important force in generating new T. gondii genotypes. Genes unique to a monomorphic version of a single parasite chromosome may have facilitated a recent population sweep of a limited number of highly successful T. gondii lineages.
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Dubey JP, Webb DM, Sundar N, Velmurugan GV, Bandini LA, Kwok OCH, Su C. Endemic avian toxoplasmosis on a farm in Illinois: Clinical disease, diagnosis, biologic and genetic characteristics of Toxoplasma gondii isolates from chickens (Gallus domesticus), and a goose (Anser anser). Vet Parasitol 2007; 148:207-12. [PMID: 17656021 DOI: 10.1016/j.vetpar.2007.06.033] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2007] [Revised: 06/11/2007] [Accepted: 06/20/2007] [Indexed: 11/27/2022]
Abstract
Clinical toxoplasmosis in chickens (Gallus domesticus) has been rarely reported in literature. Here we report that three chickens on a farm in Illinois developed neurological signs. One of these chickens was examined postmortem and it had non-suppurative encephalitis with numerous Toxoplasma gondii tachyzoites and tissue cysts. The identity of the protozoa was confirmed immunohistochemically by staining with T. gondii specific antibodies, and by transmission electron microscopy. The owner of the 3 chickens donated all 11 remaining chickens and a goose on his property for the present study. All 11 chickens and a goose were euthanized, and blood, heart, brain, and 1 leg were obtained for T. gondii examination. Antibodies to T. gondii were found in sera of all chickens with titers of 1:40 in one, 1:320 in three, and 1:640 or higher in seven chickens tested by the modified agglutination test (MAT). The goose had a MAT titer of 1:320. For isolation of T. gondii, whole heart and brain and 50 g of leg muscles were digested in an acid-pepsin solution and bioassayed in four mice for each tissue. Viable T. gondii was isolated from tissues of all 11 chickens and the goose. Genotyping of these 12 T. gondii isolates using polymorphism at the genetic loci SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, a new SAG2 and Apico revealed that all isolates had Type II alleles at all loci, indicating these T. gondii isolates belong to the predominant clonal Type II lineages. This is the first report of isolation of viable T. gondii from a domestic goose (Anser anser).
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