RESUMO
Dibothriocephalus latus and Dibothriocephalus dendriticus are found throughout the temperate and sub-arctic zones of the northern hemisphere, but they are also found in the southern core countries of South America, Chile and Argentina. Genetic characteristics of D. latus and D. dendriticus from South America have yet to be fully defined. The present study aimed to understand the genetic characteristics of D. latus and D. dendriticus from Chile by haplotype network analysis of mitochondrial cytochrome c oxidase subunit I gene (cox1) and cytochrome b gene (cob), as well as their origins. Dibothriocephalus latus and D. dendriticus plerocercoid larvae were obtained from feral and/or wild salmonids captured in Lake Llanquihue in Región de Los Lagos, and Lake Panguipulli in Región de Los Ríos, located south of central Chile. Haplotype analysis of D. latus revealed that H1 in cox1 and H2 in cob are the key haplotypes common to D. latus across the world, including Chile, and both genes exhibited limited genetic diversity in D. latus. It was assumed that D. latus was brought into South America by European and Russian immigrants in the 19th century as previously reported. In contrast, both the cox1 and cob of D. dendriticus display considerable genetic diversity, with no common haplotypes between D. dendriticus populations from Chile and the northern hemisphere. More intriguingly, two cob haplotypes (H24, H25) detected in Chilean D. dendriticus were closely linked to haplotypes (H30, H31) detected in North American D. dendriticus, strongly implying that D. dendriticus in Chile was brought by piscivorous migrating birds from North America. It has also been estimated that the D. dendriticus from Chile genetically diverged from the D. dendriticus from the northern hemisphere approximately 1.11 million years ago, long before humans migrated to the southern parts of South America.
Assuntos
Cestoides , Diphyllobothrium , Animais , Humanos , Chile/epidemiologia , Haplótipos , Cestoides/genética , Diphyllobothrium/genética , DNA Mitocondrial/genética , Variação Genética , FilogeniaRESUMO
The systematics of tapeworms in the genus Spirometra has been progressing with the accumulation of molecular genetics data, but the taxonomic status of many nominal species remains under debate. We report morphological and molecular-phylogenetic data for a Spirometra species collected from a domestic cat (Felis silvestris catus) in Chiloé Island, Chile. The Spirometra species was shown to be genetically conspecific with Spirometra decipiens complex 1 found in a Pampas fox (Lycalopex gymnocercus) from Argentina, and was closely related to a Hoary fox (Lycalopex vetulus) and rattlesnake (Crotalus durissus) from Brazil. Therefore, the presence of S. decipiens complex 1 was molecularly confirmed for the first time in Chile. The findings of the present study add useful information for the systematics of poorly known Spirometra species in South America.
Assuntos
Doenças do Gato/parasitologia , Infecções por Cestoides/veterinária , Spirometra/classificação , Animais , Animais Domésticos , Doenças do Gato/epidemiologia , Gatos , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Chile/epidemiologia , Feminino , Microscopia Eletrônica de Varredura/veterinária , Filogenia , RNA de Transferência/genética , Spirometra/genética , Spirometra/ultraestruturaAssuntos
Infecções por Ascaridida/parasitologia , Ascaridoidea/genética , Adulto , Animais , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/transmissão , Ascaridoidea/patogenicidade , Chile/epidemiologia , Feminino , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/transmissão , Produtos Pesqueiros/parasitologia , Humanos , Larva/patogenicidade , Masculino , Pessoa de Meia-IdadeRESUMO
Diphyllobothriasis caused by the infection of adult Diphyllobothrium tapeworms sporadically occurs in Chile. The occurrence of the disease is closely linked to the consumption of raw or undercooked freshwater and marine fishes. Diagnosis of diphyllobothriasis has been based on laboratory examinations of the morphological characteristics of proglottids and eggs passed in the feces. Although determination of the parasite to the species level is possible through histologic examination of proglottid specimens, the parasites of patients who only discharge eggs cannot be diagnosed to the species level. Determining the species responsible for the infection of humans and other animals in affected areas is an important component of understanding the epidemiologic and enzootic characteristics of any infectious disease. We therefore compared the classification results obtained using a molecular approach with those obtained from morphological and histopathological examination of proglottids or eggs from five Chilean individuals with diphyllobothriasis. DNA analysis confirmed that the causative Diphyllobothrium species in Chile were first identified as Diphyllobothrium latum and Diphyllobothrium pacificum at least. Furthermore, mitochondrial cytochrome c oxidase subunit 1 gene analysis also supported the hypothesis that D. latum from Chile originated from Europe.
Assuntos
Difilobotríase/parasitologia , Diphyllobothrium/classificação , Diphyllobothrium/isolamento & purificação , Adolescente , Adulto , Animais , Pré-Escolar , Chile , DNA de Helmintos/química , DNA de Helmintos/genética , Diphyllobothrium/anatomia & histologia , Diphyllobothrium/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Proteínas de Helminto/genética , Humanos , Masculino , Proteínas Mitocondriais/genética , Epidemiologia Molecular , Dados de Sequência Molecular , Análise de Sequência de DNA , Adulto JovemRESUMO
The study conducted in the Cocal dos Alves municipality, located in the Piracuruca region of Piauí State, Brazil in November of 2003 was based on both a socio-behavioral survey and analysis of serum antibodies and parasitic materials. Pig raising is the main economic activity with 91.4% using extensive farming. On the studied population, 54.3% of people did not apply any sanitary measures to wastewater, 45.7% used septic tanks, and 69.1% consumed water without treatment. The data collected indicated the occurrence and active transmission of the taeniasis-cysticercosis complex in the region. One of seven voluntary persons was positive in antibody-ELISA tests using both native and recombinant antigens. Multiplex PCR and DNA sequencing of cyst samples obtained from a pig revealed the presence of the Afro-American genotype of Taenia solium. This study revealed the occurrence of human and porcine cysticercosis in the Piracuruca region of Piauí State, middle-north of Brazil.
Assuntos
Doenças Transmissíveis Emergentes/veterinária , Cisticercose/transmissão , Cisticercose/veterinária , Taenia solium/imunologia , Animais , Brasil/epidemiologia , Doenças Transmissíveis Emergentes/diagnóstico , Doenças Transmissíveis Emergentes/epidemiologia , Cisticercose/epidemiologia , Cisticercose/fisiopatologia , Ensaio de Imunoadsorção Enzimática , Humanos , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
Cysticercosis caused by infection with embryonated eggs of Taenia solium is an important cause of neurological disease worldwide. On the basis of mitochondrial DNA analysis, T. solium is divided into 2 (African/American and Asian) genotypes. Glycoproteins (GPs) in cyst fluid purified from the 2 genotypes of T. solium were characterized and compared with the recombinant chimeric T. solium-Ag1V1/Ag2 protein (Rec-Ag1V1/Ag2) as serodiagnostic antigens. Immunoblot analysis revealed that banding patterns of GPs differed between the 2 genotypes because of posttranslation modification, especially glycosylation. The comparison of native GPs with Rec-Ag1V1/Ag2 by enzyme-linked immunosorbent assay demonstrated that there was no statistical difference in sensitivity. In addition, the conservation of the genes encoding Ag1V1 and Ag2 in T. solium worldwide was verified. These results indicate that Rec-Ag1V1/Ag2 has great potential for usefulness in serodiagnosis as an alternative to native antigens.
Assuntos
Antígenos de Helmintos/imunologia , Cisticercose/diagnóstico , Glicoproteínas/imunologia , Proteínas de Helminto/imunologia , Taenia solium/imunologia , África , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Antígenos de Helmintos/genética , Ásia , Western Blotting , Ensaio de Imunoadsorção Enzimática , Glicoproteínas/genética , Glicosilação , Proteínas de Helminto/genética , Humanos , Soros Imunes/imunologia , Dados de Sequência Molecular , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Alinhamento de Sequência , América do Sul , Especificidade da Espécie , Suínos , Taenia solium/genéticaRESUMO
Lung carcinogenesis is a multistep process whose molecular alterations can be studied in mouse models. Urethane, a specific lung tumor carcinogen, can induce adenomas in mice. Mouse lung alveolar cells reportedly generate lung neoplasms, and express connexins 26, 32, 43 and 46. The aim of the present study was to evaluate the expression of connexins in urethane-induced lung adenomas. Fifteen-day-old CD1 male mice received 2 i.p. injections of urethane (1.5 g/kg bw). The mice were euthanized 25 weeks after urethane injection, and lung adenomas were quantified. Lung tissue and lung adenomas were harvested and the RNA was extracted. The expression of connexins 26, 32, 43 and 46 was evaluated by Real-Time PCR, and these proteins were identified by Western blot. Immunohistochemistry revealed the distribution pattern of these connexins in lung tissue and adenomas. The treatment with urethane was associated with the downregulation of Cx26, 32 and 46 expressions, and with the upregulation of Cx43 expression in lung tissue. Surprisingly, in lung adenomas Cx32 and Cx43 expressions were not detected, although the expression of connexins 26 and 46 was present. Western blot and immunohistochemistry corroborated the RT-PCR data. These results may indicate a role of Cx32 and Cx43 in urethane-induced lung carcinogenesis, since their absence may contribute to the development of urethane induced lung tumors. The role of Cx26 and Cx46 is yet to be determined.
Assuntos
Adenoma/metabolismo , Carcinógenos/toxicidade , Conexinas/biossíntese , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/biossíntese , Uretana/toxicidade , Adenoma/induzido quimicamente , Adenoma/genética , Animais , Carcinógenos/farmacologia , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Conexinas/genética , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Uretana/farmacologiaRESUMO
To evaluate the prevalence of toxocariasis in children in Jaboatão dos Guararapes, Pernambuco in northeastern Brazil, 215 serum samples were examined by an enzyme-linked immunosorbent assay (ELISA) using a recombinant Toxocara canis antigen. In the ELISA, 26 (12.1%) of 215 subjects were positive. In a dot-blot assay using 53 of 215 serum samples, the diagnostic results correlated with those obtained by the ELISA. Moreover, it has been confirmed that the recombinant T. canis antigen was highly specific for toxocariasis by ELISA using serum samples positive for antibody to Ascaris lumbricoides. Considering the specificity of the recombinant antigen to toxocariasis, the ELISA or dot-blot assay using the recombinant T. canis antigen is recommended in tropical and sub-tropical regions where various parasitic infections are commonly endemic.
Assuntos
Antígenos de Helmintos/imunologia , Toxocara canis/imunologia , Toxocaríase/diagnóstico , Animais , Antígenos de Helmintos/genética , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática , Prevalência , Proteínas Recombinantes/imunologia , Testes Sorológicos , Sorologia , Toxocaríase/parasitologiaRESUMO
Gap junction intercellular communication capacity and connexin expression are reportedly decreased in human lung cancer. The mechanisms by which connexins, the gap junction proteins, act as tumor suppressors are unclear. In order to understand the involvement of connexins in tumorigenesis, we analyzed the effect of the heterologous deletion of Gja1 [the connexin43 (Cx43) gene] on the development of lung adenomas in mice. Heterozygous (Cx43(+/-)) and wild-type mice (Cx43(+/+)) were treated or not with single doses of urethane at 15 and 17 days after birth. Twenty-five weeks later, both the number and size of nodules were increased in Cx43(+/-) mice as compared with Cx43(+/+) mice. Moreover, the lesions were histologically more aggressive in the heterozygous mice. However, no increase in spontaneous lesions was observed in the lungs of untreated Cx43(+/-) mice. Heterozygous mice effectively presented lower expression of Cx43 genes and decreased amounts of Cx43. In conclusion, our results indicate that deletion of one allele of the Cx43 gene clearly favors the carcinogenic effect of urethane administration and results in a higher susceptibility to lung adenoma formation in mice.
Assuntos
Adenoma/induzido quimicamente , Carcinógenos/toxicidade , Conexina 43/genética , Neoplasias Pulmonares/induzido quimicamente , Uretana/toxicidade , Adenoma/genética , Adenoma/patologia , Animais , Suscetibilidade a Doenças , Deleção de Genes , Heterozigoto , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fase S/efeitos dos fármacosRESUMO
Immunodetection of human IgG anti-Toxocara canis was developed based on ELISA and on the use of polysiloxane/polyvinyl alcohol (POS/PVA) beads. A recombinant antigen was covalently immobilized, via glutaraldehyde, onto this hybrid inorganic-organic composite, which was prepared by the sol-gel technique. Using only 31.2 ng antigen per bead, a peroxidase conjugate dilution of 1:10,000 and a serum dilution of 1:200 were adequate for the establishment of the procedure. This procedure is comparable to that which utilizes the adsorption of the antigen to conventional PVC plates. However, the difference between positive and negative sera mean absorbances was larger for this new glass based assay. In addition to the performance of the POS/PVA bead as a matrix for immunodetection, its easy synthesis and low cost are additional advantages for commercial application.