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1.
Acta Trop ; 248: 107022, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37716667

RESUMO

Congenital toxoplasmosis may cause abortion, neonatal death, or foetal abnormalities. Despite little information from human studies, a genetic influence over congenital disease was demonstrated and, host genome have been implicated to resistance/susceptibility to Toxoplasma gondii infection in both human and mice. It was previously shown that BALB/c mice (H2d) were more resistant to congenital toxoplasmosis than C57BL/6 mice (H2b). However, it is unclear whether these differences are attributable to the MHC haplotype or to other components of the mouse's genetic background. Therefore, in this work, we intend to address this question by investigating the pregnancy outcome in H2d -congenic C57BL/6 mice (C57BL/KsJ-H2d) and H2b-congenic BALB/c mice (CB10-H2-H2b). For this, animals were infected by intragastric route on the first day of pregnancy and examined on days 8 (8dP/8dI) or 18 (18dP/18dI) of gestation and infection. The pregnancy outcome, parasite burden, systemic cytokine profile and antibody response to infection were evaluated. Infected mice showed adverse pregnancy outcomes, in parallel low parasite detection in the uterus/placenta, being that the C57BL/KsJ showed the worst results in relation to CB10-H2 mice. Both mouse lineages showed an increase in IFN-γ and TNF levels systemically on 8dP/8dI and on 18dP/18dI, and C57BL/KsJ showed an increase in IL-6 levels in both gestation/infection periods. Additionally, C57BL/KsJ showed 7- and 7-fold increase in IL-6, 4- and 2.5-fold increase in IFN-γ and, 6- and 4-fold increase in TNF production on 8dP/8dI and 18dP/18dI, respectively in association with 1.5-fold decrease in TGF-ß levels on 8dP/8dI compared to CB10-H2 mice. In conclusion, the high IFN-γ and TNF serum levels observed in C57BL/KsJ (H2d) and CB10-H2 (H2b) mice were involved in the poor pregnancy outcomes in congenital toxoplasmosis. In addition, the higher IFN-γ, IL-6 and TNF levels detected in C57BL/KsJ in relation to CB10-H2 mice on 8dP/8dI seem to be related to the genetic background of C57BL/6J mice that may have contributed to the worse pregnancy outcome in this mouse lineage.


Assuntos
Toxoplasma , Toxoplasmose Animal , Toxoplasmose Congênita , Animais , Feminino , Humanos , Camundongos , Gravidez , Suscetibilidade a Doenças , Haplótipos , Interleucina-6/genética , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Toxoplasma/genética , Toxoplasmose Animal/parasitologia , Toxoplasmose Congênita/genética , Histocompatibilidade
2.
Tissue Cell ; 79: 101952, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36209640

RESUMO

Notch signaling pathway plays a crucial role in cellular fate across species, being important for the differentiation and development of several cell types. The aim of this study was to evaluate the effect of Notch inhibition pathway by dibenzazepine (DBZ) in histological and inflammatory alterations and, tissue parasitism in acute Toxoplasma gondii infection. For this, C57BL/6 mice were treated with DBZ before infection with T. gondii, and the small intestine, lungs and liver were analyzed. The genes related to Notch signaling pathway were assayed through qPCR in the organs, and cytokine measurement was performed in serum samples. In the small intestine, T. gondii infection impaired the Hes1 and Math1 mRNA expressions, increased the inflammation and decreased goblet and Paneth cell numbers. The DBZ-treatment was able to partially preserve these cells, however, the parasitism and inflammation were not altered. In parallel, the high IL-2, IL-6, TNF and, IFN-γ levels induced by infection were not changed with the DBZ treatment, with the IFN-γ levels even higher. In contrast, in the liver and lungs, the DBZ-treatment diminished parasitism and inflammation. Our results highlight that Notch pathway inhibition in T.gondii infection results in different parasitological and inflammatory outcomes depending on the organ analyzed.


Assuntos
Dibenzazepinas , Toxoplasmose , Animais , Camundongos , Camundongos Endogâmicos C57BL , Dibenzazepinas/farmacologia , Transdução de Sinais , Inflamação/tratamento farmacológico
3.
Infect Immun ; 90(7): e0002922, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35658510

RESUMO

5-Lipoxygenase (5-LO) is an enzyme required for the production of leukotrienes and lipoxins and interferes with parasitic infections. In vitro, Toxoplasma gondii inhibits leukotriene B4 (LTB4) production, and mice deficient in 5-LO are highly susceptible to infection. The aim of this study was to investigate the effects of the pharmacological inhibition of the 5-LO pathway and exogenous LTB4 supplementation during experimental toxoplasmosis. For this purpose, susceptible C57BL/6 mice were orally infected with T. gondii and treated with LTB4 or MK886 (a selective leukotriene inhibitor through inhibition of 5-LO-activating protein [FLAP]). The parasitism, histology, and immunological parameters were analyzed. The infection decreased 5-LO expression in the small intestine, and treatment with MK886 reinforced this reduction during infection; in addition, MK886-treated infected mice presented higher intestinal parasitism, which was associated with lower local interleukin-6 (IL-6), interferon gamma (IFN-γ), and tumor necrosis factor (TNF) production. In contrast, treatment with LTB4 controlled parasite replication in the small intestine, liver, and lung and decreased pulmonary pathology. Interestingly, treatment with LTB4 also preserved the number of Paneth cells and increased α-defensins expression and IgA levels in the small intestine of infected mice. Altogether, these data demonstrated that T. gondii infection is associated with a decrease in 5-LO expression, and on the other hand, treatment with the 5-LO pathway product LTB4 resulted in better control of parasite growth in the organs, adding to the knowledge about the pathogenesis of T. gondii infection.


Assuntos
Parasitos , Toxoplasma , Toxoplasmose , Animais , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/metabolismo , Leucotrieno B4 , Lipoxigenase , Camundongos , Camundongos Endogâmicos C57BL , Parasitos/metabolismo
4.
Front Immunol ; 13: 879158, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35619717

RESUMO

The enzyme heme oxygenase-1 (HO-1) has cytoprotective effects by catalyzing the degradation of heme to produce carbon monoxide, iron and biliverdin. Furthermore, HO-1 activity has been associated with successful pregnancy. On the other hand, in the context of certain inflammatory conditions, HO-1 can induce iron overload and cell death. To investigate the role of HO-1 in gestational malaria, pregnant BALB/c mice were infected with Plasmodium berghei ANKA in early, mid and late gestation. We found that malaria affected the pregnancy outcome in the three periods evaluated. However, only poor pregnancy outcomes in early pregnancy were related to HO-1 upregulation, iron overload, lipid peroxidation and necrosis of the decidua, which were prevented by HO-1 inhibition. In conclusion, HO-1 expression must be finely tuned in gestational malaria to avoid the deleterious effect of increased enzyme activity.


Assuntos
Heme Oxigenase-1 , Malária , Resultado da Gravidez , Protoporfirinas , Animais , Feminino , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/metabolismo , Sobrecarga de Ferro , Peroxidação de Lipídeos , Malária/tratamento farmacológico , Camundongos , Plasmodium berghei , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Protoporfirinas/farmacologia
5.
J Ethnopharmacol ; 273: 114019, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-33716084

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sulfadiazine and pyrimethamine are the two drugs used as part of the standard therapy for toxoplasmosis, however; they may cause adverse side effects and fail to prevent relapse in many patients, rendering infected individuals at risk of reactivation upon becoming immunocompromised. Extracts from various parts of Annona muricata have been widely used medicinally for the management, control and/or treatment of several human diseases, acting against parasites that cause diseases in humans. AIM OF THE STUDY: This study was performed to investigate the action of the ethanolic extract of A. muricata (EtOHAm) and its fractions in the control of the apicomplexan parasite Toxoplasma gondii in vitro and in vivo, and the effect of EtOHAm on the inflammatory response and lipid profile alteration induced by in vivo T. gondii infection. MATERIALS AND METHODS: The cytotoxicity of EtOHAm and its fractions ethyl acetate (EtOAcAm), n-butanol (BuOHAm), aqueous (H2OAm), hexane (HexAm) and dichloromethane (CH2Cl2Am) was evaluated in NIH/3T3 fibroblasts using the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The cells were infected with T. gondii, treated with the extracts, and parasite proliferation was analyzed. For the in vivo experiments, C57BL/6 mice were orally infected with T. gondii and, treated with different concentrations of extract fractions that were effective in vitro (EtOHAm, EtOAcAm, HexAm and CH2Cl2Am). Tissue parasitism, histological alterations, systemic cytokine and lipid profile were investigated. RESULTS: EtOHAm, EtOAcAm, BuOHAm, H2OAm presented low cytotoxicity until doses of 200 µg/mL, while HexAm and CH2Cl2Am presented toxicity from doses of 100µg/mL. EtOHAm, HexAm and CH2Cl2Am decreased the parasitism in vitro, presenting a therapeutic index of 2.62, 2.44, and 2.96, respectively. In vivo, EtOHAm, HexAm and CH2Cl2Am improved the survival rate of infected animals, however, only EtOHAm was able to decrease the parasitism in the small intestine and lung. Additionally, EtOHAm decreased the systemic interferon (IFN)-γ and tumor necrosis factor (TNF) systemically in infected mice, and was able to maintain the triglycerides and very-low-density lipoprotein (VLDL) lipid fractions at similar levels to uninfected animals. Although treatment with EtOHAm could not control the inflammation induced by oral infection in the tissues analyzed, it was able to preserve the number of goblet cells in the small intestine. CONCLUSIONS: Ethanolic A. muricata leaf extract could be considered as a good candidate for the development of a complementary/alternative therapy against toxoplasmosis, and also as an anti-inflammatory alternative for decreasing TNF and IFN-γ concentrations and lipid fractions in specific diseases.


Assuntos
Annona/química , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Toxoplasma/efeitos dos fármacos , Toxoplasmose Animal/tratamento farmacológico , Animais , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Fitoterapia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química
6.
Parasite Immunol ; 43(4): e12811, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33247953

RESUMO

BACKGROUND: Toxoplasma gondii is a protozoan with worldwide distribution and triggers a strong Th1 immune response in infected susceptible hosts. On the contrary, most helminth infections are characterized by Th2 immune response and the use of helminth-derived antigens to regulate immune response in inflammatory disorders has been broadly investigated. OBJECTIVES: The aim of this study was to investigate whether treatment with Strongyloides venezuelensis antigen extract (SvAg) would alter immune response against T gondii. METHODS: C57BL/6 mice were orally infected with T gondii and treated with SvAg, and parasitological, histological and immunological parameters were investigated. RESULTS: It was observed that SvAg treatment improved survival rates of T gondii-infected mice. At day 7 post-infection, the parasite load was lower in the lung and small intestine of infected SvAg-treated mice than untreated infected mice. Remarkably, SvAg-treated mice infected with T gondii presented reduced inflammatory lesions in the small intestine than infected untreated mice and decreased intestinal and systemic levels of IFN-γ, TNF-α and IL-6. In contrast, SvAg treatment increased T gondii-specific IgA serum levels in infected mice. CONCLUSIONS: S venezuelensis antigen extract has anti-parasitic and anti-inflammatory properties during T gondii infection suggesting as a possible alternative to parasite and inflammation control.


Assuntos
Antígenos de Helmintos/uso terapêutico , Strongyloides/imunologia , Toxoplasmose/tratamento farmacológico , Animais , Citocinas/análise , Citocinas/sangue , Feminino , Imunoglobulina A/análise , Imunoglobulina A/sangue , Intestino Delgado/parasitologia , Intestino Delgado/patologia , Pulmão/parasitologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Carga Parasitária , Toxoplasmose Animal/tratamento farmacológico
7.
Biosci. j. (Online) ; 36(6): 2172-2185, 01-11-2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1148284

RESUMO

Canine demodicosis is a common inflammatory parasitic skin disease caused by Demodex mites. House dust mites, such as Dermatophagoides spp., play an important role in the pathogenesis of canine atopic dermatitis (AD). The goal of this experimental work was to investigate whether demodectic dogs could be previously exposed/sensitized to house dust mites' antigens. First the prevalence of demodicosis in a southeastern region of Brazil was investigated by analyzing clinical files of dogs that were admitted to a Veterinary Hospital. Subsequently, the IgG responses to Dermatophagoides pteronyssinus (Dp) and Dermatophagoides farinae (Df) and IgE to D.pteronyssinus (Dp) were evaluatedin two groups, AD or demodicosis dogs. Additionally, the major IgE-binding Dp proteins that are recognized by sera from dogs with demodicosis and AD were evaluated. A total of 2,599 clinical files were analyzed to identify the major parasitic skin diseases in dogs from this region, considering the age, sex and breed of the animals. The epidemiological study identified 111 animals with skin diseases; from these 20.7% presented demodicosis. Afterwards, serum samples were obtained from another groups of demodicosis, AD, and healthy dogs, and analyzed for Dp and Df-specific IgG, and IgE antibody levels, Dp IgG avidity by ELISA and IgE-binding Dp-specific proteins by immunoblot. IgG and IgE antibodies to Dp were detected in sera from additional groups of dogs with AD, demodicosis or healthy, with higher IgE levels to Dp in AD than demodectic or healthy dogs. IgG to Df was detected, despite with smaller levels compared to Dp in sera from demodectic dogs, and also in healthy dogs. Immunoblot showed IgE-binding to Dp proteins in sera of dogs with demodicosis and AD; with strong reactivity for the 72 and 116 kDa antigens detected by sera from demodicosis dogs. However, sera from healthy dogs >12 months old also presented reactivity to these bands. In conclusion, the detection of Dp-IgG and IgE antibodies in sera from demodectic dogs indicates previous exposure and sensitization to the house dust mite, respectively, more than cross-reactivity between demodex mites and Dp antigens detected by canine antibodies. Additionally, higher Dp-specific IgE levels were found in dogs with AD compared with those with demodicosis or healthy, suggesting that Dp-specific IgE could better discriminate dogs with AD from healthy ones or even those with demodicosis.


Demodicose canina é uma doença inflamatória comum da pele causada por ácaros do gênero Demodex. Ácaros da poeira doméstica como Dermatophagoides spp. desempenham papel importante na patogênese da dermatite atópica canina (DA). O objetivo desse trabalho experimental foi investigar se cães com demodicose poderiam ser previamente expostos/sensibilizados com antígenos de ácaros da poeira doméstica. A princípio, investigou-se a prevalência de demodicose em uma região sudeste do Brasil, analisando-se prontuários clínicos de cães admitidos em um Hospital Veterinário. Posteriormente, as respostas de IgG a Dermatophagoides pteronyssinus (Dp) e D. farinae (Df) e IgE a D. pteronyssinus (Dp) foram avaliadas em dois grupos, DA ou demodicose. Também foram avaliadas as principais proteínas Dp reconhecidas por anticorpo IgE presente em soros de cães com demodicose e DA. Um total de 2.599 prontuários clínicos foram analisados para identificar as principais doenças parasitárias da pele em cães dessa região, considerando a idade, sexo e raça dos animais. O estudo epidemiológico detectou 111 animais com doenças de pele e destes, 20,7% apresentavam demodicose. Posteriormente, amostras de soro foram obtidas de outros grupos de cães com demodicose, DA ou saudáveis, e analisadas quanto aos níveis de IgG e IgE específicos para Dp e Df, avidez de IgG a Dp por ELISA e proteínas específicas de Dp reconhecidas por IgE por immunoblot. Anticorpos IgG e IgE para Dp foram detectados em soros de grupos adicionais de cães com DA, demodicose ou saudáveis, com níveis mais altos de IgE para Dp na DA do que no soro de animais saudáveis. Níveis de IgG específicos para Df foram detectados, apesar serem menores em comparação com os detectados para Dp em soros de cães demodéticos, e também em cães saudáveis. A análise de immunoblot demonstrou detecção de IgE para proteinas de Dp em soros de cães com demodicose e DA; com forte reatividade para os antígenos de 72 e 116 kDa detectados por soros de cães com demodicose. No entanto, soros de cães saudáveis > 12 meses de idade também apresentaram reatividade a essas bandas. Em conclusão, a detecção de anticorpos Dp-IgG e IgE específicos em soros de cães demodéticos indica exposição prévia e sensibilização aos ácaros, respectivamente, mais do que reatividade cruzada entre ácaros Demodex e antígenos Dp detectados por anticorpos caninos. Além disso, níveis de Dp-IgE específicos mais elevados encontrados em cães com DA, sugerem que esses anticorpos poderiam discriminar melhor cães com DA daqueles saudáveis ou mesmo demodéticos.


Assuntos
Imunoglobulina E , Imunoglobulina G , Dermatophagoides pteronyssinus , Cães
8.
Microorganisms ; 8(4)2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32295126

RESUMO

Iron is an important constituent of our environment, being necessary for both mammalian and pathogenic protozoa survival. Iron-containing proteins exert a wide range of biological processes such as biodegradation and biosynthesis, as well as immune function, fetal development, and physical and mental well-being. This work aimed to investigate the effect of iron deprivation in Toxoplasma gondii infection outcome. C57BL/6 mice were orally infected with T. gondii and treated with an iron chelator, deferoxamine, or supplemented with iron (ferrous sulfate), and the parasitism as well as immunological and histological parameters were analyzed. It was observed that the infection increased iron accumulation in the organs, as well as systemically, and deferoxamine treatment diminished the iron content in serum samples and intestine. The deferoxamine treatment decreased the parasitism and inflammatory alterations in the small intestine and lung. Additionally, they partially preserved the Paneth cells and decreased the intestinal dysbiosis. The ferrous sulfate supplementation, despite not significantly increasing the parasite load in the organs, increased the inflammatory alterations in the liver. Together, our results suggest that iron chelation, which is commonly used to treat iron overload, could be a promising medicine to control T. gondii proliferation, mainly in the small intestine, and consequently inflammation caused by infection.

9.
Front Microbiol ; 11: 429, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256479

RESUMO

Phenolic glycolipid I (PGL-I) is an abundant antigen on the Mycobacterium leprae cell wall, commonly used for operational classification of leprosy patients. Our aim was to develop PGL-I mimotopes with similar characteristics and functions of the native antigen. We have used a random peptide phage display (PD) library for selections against the monoclonal antibody anti-PGL-I. After three selection cycles, six peptides were identified. All sequences were interspersed by a spacer generating a chimeric peptide (PGLI-M3) that was artificially synthesized. The highly reactive peptide was submitted to a reverse PD selection with a single-chain Fv (scFv) antibody fragment combinatorial library. The most reactive scFv was then validated by enzyme-linked immunosorbent assay (ELISA) against both native PGL-I and two derived synthetic (NDO and ND-O-HSA). We have further proved the scFv specificity by detecting M. leprae bacilli in leprosy lesions through immunohistochemistry. We then described its applicability in ELISA for all clinical forms and household contacts (HC). Afterward, we showed differential binding affinities of PGLI-M3 to sera (anti-PGL-I IgM) from all leprosy clinical forms through surface plasmon resonance (SPR). ELISA IgM detection showed 89.1% sensitivity and 100% specificity, considering all clinical forms. Positivity for anti-PGL-I IgM was twofold higher in both HC and patients with paucibacillary forms in hyperendemic regions than in endemic ones. The SPR immunosensor was able to differentiate clinical forms with 100% accuracy. This is the first time that a PGL-I mimotope has efficiently mimicked the carbohydrate group of the M. leprae antigen with successful immunoassay applications and may become a substitute for the native antigen.

10.
Artigo em Inglês | MEDLINE | ID: mdl-28487847

RESUMO

Toxoplasma gondii is known to cause congenital infection in humans and animals and severe disease in immunocompromised individuals; consequently development of vaccines against the parasite is highly necessary. Under stress conditions, T. gondii expresses the highly immunogenic heat shock protein 70 (TgHSP70). Here, we assessed the protective efficacy of rTgHSP70 immunization combined with Alum in oral ME-49 T. gondii infection and the mechanisms involved on it. It was observed that immunized mice with rTgHSP70 or rTgHSP70 adsorbed in Alum presented a significantly reduced number of cysts in the brain that was associated with increased iNOS+ cell numbers in the organ, irrespective the use of the adjuvant. Indeed, ex vivo experiments showed that peritoneal macrophages pre-stimulated with rTgHSP70 presented increased NO production and enhanced parasite killing, and the protein was able to directly stimulate B cells toward antibody producing profile. In addition, rTgHSP70 immunization leads to high specific antibody titters systemically and a mixed IgG1/IgG2a response, with predominance of IgG1 production. Nonetheless, it was observed that the pretreatment of the parasite with rTgHSP70 immune sera was not able to control T. gondii internalization and replication by NIH fibroblast neither peritoneal murine macrophages, nor anti-rTgHSP70 antibodies were able to kill T. gondii by complement-mediated lysis, suggesting that these mechanisms are not crucial to resistance. Interestingly, when in combination with Alum, rTgHSP70 immunization was able to reduce inflammation in the brain of infected mice and in parallel anti-rTgHSP70 immune complexes in the serum. In conclusion, immunization with rTgHSP70 induces massive amounts of iNOS expression and reduced brain parasitism, suggesting that iNOS expression and consequently NO production in the brain is a protective mechanism induced by TgHSP70 immunization, therefore rTgHSP70 can be a good candidate for vaccine development against toxoplasmosis.


Assuntos
Encéfalo/parasitologia , Cistos/parasitologia , Óxido Nítrico/metabolismo , Toxoplasma/efeitos dos fármacos , Toxoplasmose/imunologia , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/farmacologia , Adjuvantes Imunológicos , Compostos de Alúmen/farmacologia , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/farmacologia , Linfócitos B/efeitos dos fármacos , Encéfalo/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cistos/patologia , Citocinas/sangue , Feminino , Fibroblastos , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/imunologia , Proteínas de Choque Térmico HSP70/farmacologia , Imunoglobulina G/sangue , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II , Fenótipo , Células RAW 264.7 , Baço , Toxoplasmose/tratamento farmacológico , Vacinação
11.
PLoS One ; 12(4): e0174857, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28423045

RESUMO

There is growing evidence in the literature suggesting that caste differentiation in the stingless bee, Melipona scutellaris, and other bees in the genus Melipona, is triggered by environmental signals, particularly a primer pheromone. With the proper amount of food and a chemical stimulus, 25% of females emerge as queens, in agreement with a long-standing "two loci/two alleles model" proposed in the 1950s. We surmised that these larvae must be equipped with an olfactory system for reception of these chemical signals. Here we describe for the first time the diversity of antennal sensilla in adults and the morphology of larvae of M. scutellaris. Having found evidence for putative olfactory sensilla in larvae, we next asked whether olfactory proteins were expressed in larvae. Since the molecular basis of M. scutellaris is still unknown, we cloned olfactory genes encoding chemosensory proteins (CSP) and odorant-binding proteins (OBPs) using M. scutellaris cDNA template and primers designed on the basis CSPs and OBPs previously reported from the European honeybee, Apis mellifera. We cloned two CSP and two OBP genes and then attempted to express the proteins encoded by these genes. With a recombinant OBP, MscuOBP8, and a combinatorial single-chain variable fragment antibody library, we generated anti-MscuOBP8 monoclonal antibody. By immunohistochemistry we demonstrated that the anti-MscuOBP8 binds specifically to the MscuOBP8. Next, we found evidence that MscuOBP8 is expressed in M. scutellaris larvae and it is located in the mandibular region, thus further supporting the hypothesis of olfactory function in immature stages. Lastly, molecular modeling suggests that MscuOBP8 may function as a carrier of primer pheromones or other ligands.


Assuntos
Abelhas/genética , Proteínas de Insetos/genética , Larva/genética , Percepção Olfatória/genética , Receptores Odorantes/genética , Sensilas/metabolismo , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Abelhas/crescimento & desenvolvimento , Abelhas/metabolismo , Abelhas/ultraestrutura , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Clonagem Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Imuno-Histoquímica , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/ultraestrutura , Modelos Moleculares , Biblioteca de Peptídeos , Feromônios/química , Feromônios/genética , Feromônios/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Receptores Odorantes/química , Receptores Odorantes/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sensilas/crescimento & desenvolvimento , Sensilas/ultraestrutura , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/metabolismo
12.
PLoS One ; 9(5): e96527, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24801069

RESUMO

The heat shock protein of Toxoplasma gondii (TgHSP70) is a parasite virulence factor that is expressed during T. gondii stage conversion. To verify the effect of dexamethasone (DXM)-induced infection reactivation in the TgHSP70-specific humoral immune response and the presence of the protein in the mouse brain, we produced recombinant TgHSP70 and anti-TgHSP70 IgY antibodies to detect the protein, the specific antibody and levels of immune complexes (ICs) systemically, as well as the protein in the brain of resistant (BALB/c) and susceptible (C57BL/6) mice. It was observed higher TgHSP70-specific antibody titers in serum samples of BALB/c compared with C57BL/6 mice. However, the susceptible mice presented the highest levels of TgHSP70 systemically and no detection of specific ICs. The DXM treatment induced increased parasitism and lower inflammatory changes in the brain of C57BL/6, but did not interfere with the cerebral parasitism in BALB/c mice. Additionally, DXM treatment decreased the serological TgHSP70 concentration in both mouse lineages. C57BL/6 mice presented high expression of TgHSP70 in the brain with the progression of infection and under DXM treatment. Taken together, these data indicate that the TgHSP70 release into the bloodstream depends on the death of the parasites mediated by the host immune response, whereas the increased TgHSP70 expression in the brain depends on the multiplication rate of the parasite.


Assuntos
Encéfalo/imunologia , Replicação do DNA/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Imunidade Humoral/imunologia , Parasitos/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Animais , Encéfalo/parasitologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Toxoplasmose Animal/parasitologia
13.
Vet Res ; 44: 89, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24088531

RESUMO

Heme oxygenase-1 (HO-1) is an enzyme that catabolizes free heme, which induces an intense inflammatory response. The expression of HO-1 is induced by different stimuli, triggering an anti-inflammatory response during biological stress. It was previously verified that HO-1 is able to induce indoleamine 2,3-dioxygenase (IDO), an enzyme that is induced by IFN-γ in Toxoplasma gondii infection. To verify the role of HO-1 during in vivo T. gondii infection, BALB/c and C57BL/6 mice were infected with the ME49 strain and treated with zinc protoporphyrin IX (ZnPPIX) or hemin, which inhibit or induce HO-1 activity, respectively. The results show that T. gondii infection induced high levels of HO-1 expression in the lung of BALB/c and C57BL6 mice. The animals treated with ZnPPIX presented higher parasitism in the lungs of both lineages of mice, whereas hemin treatment decreased the parasite replication in this organ and in the small intestine of infected C57BL/6 mice. Furthermore, C57BL/6 mice infected with T. gondii and treated with hemin showed higher levels of IDO expression in the lungs and small intestine than uninfected mice. In conclusion, our data suggest that HO-1 activity is involved in the control of T. gondii in the lungs of both mouse lineages, whereas the hemin, a HO-1 inducer, seems to be involved in the control of parasitism in the small intestine of C57BL/6 mice.


Assuntos
Regulação da Expressão Gênica , Heme Oxigenase-1/genética , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Toxoplasma/fisiologia , Toxoplasmose Animal/enzimologia , Toxoplasmose Animal/genética , Animais , Citocinas/genética , Citocinas/metabolismo , Feminino , Heme Oxigenase-1/metabolismo , Hemina/farmacologia , Imuno-Histoquímica , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Intestino Delgado/enzimologia , Intestino Delgado/metabolismo , Intestino Delgado/parasitologia , Pulmão/enzimologia , Pulmão/metabolismo , Pulmão/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Protoporfirinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Toxoplasmose Animal/parasitologia
14.
Eng. sanit. ambient ; 18(3): 263-274, July-Sept/2013. tab, graf
Artigo em Português | LILACS | ID: lil-690021

RESUMO

A modelagem e otimização da disposição espacial de unidades de reservação que constituem os Sistemas Urbanos de Distribuição de Água (SUDA) são abordadas neste estudo sob a perspectiva do apoio à decisão no planejamento desses sistemas. Tendo em vista os avanços e técnicas encontrados nos Sistemas de Informação Geográfica (SIG) e a possibilidade de utilizá-los como Sistema de Apoio a Decisão Espacial (SADE), este trabalho apresenta uma metodologia que viabiliza a tomada de decisão em planejamento de SUDA. Utilizando critérios espacializados, são gerados mapas de riscos de desabastecimento em lotes urbanos que podem servir como indicadores em ações de planejamento e gestão, assim como são mapeadas zonas consideradas como ótimas para a localização de novas unidades de reservação, as quais constituem diretrizes no planejamento para expansão dos SUDA.


This research presents a modeling and optimizing alternative for water reservoirs placement of an Urban Water Supply Systems (UWSS). These systems are considered as decision making support systems for planning. The focus is the advances and techniques found in the Geographical Information Systems (GIS) and the possibility to use it as Spatial Decision Support System (SDSS). This research presents a new methodology for decision making in a planning of UWSS. Risk Maps are produced using multi-criteria evaluation techniques for urban parcels. They can indicate some planning and management actions. It is established a suitability zoning to locate new water reservoirs units, which can support guidelines and planning for expansion of system.

15.
Int J Parasitol ; 42(4): 341-52, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22366549

RESUMO

Congenital toxoplasmosis is associated with adverse pregnancy outcome. Despite the type 1 immune response, C57BL/6 mice are more susceptible than BALB/c mice to Toxoplasma gondii infection. Additionally, successful pregnancy appears to be correlated with type 2 T helper maternal immunity and regulatory T cells. In order to investigate the mechanisms of susceptibility/resistance to congenital toxoplasmosis in mice with different genetic backgrounds and the influence of inducible nitric oxide synthase in pregnancy outcome, groups of C57BL/6, BALB/c and C57BL/6 iNOS(-/-) females were orally infected with T. gondii ME-49 strain on day 1 of pregnancy and were sacrificed on day 8 p.i. and day 19 p.i. The uterus and placenta were evaluated for the foetal resorption rate, parasite load, immunological and histological changes. C57BL/6 mice presented inflammatory foci in the decidua (endometrium) of the uterus at a higher frequency than BALB/c mice on day 8 p.i., and a large number of pregnant C57BL/6 mice presented necrotic implantation sites. The parasite was seldom found in the uterus or placenta of either lineage of mice. Interestingly, there was no observed difference in inducible nitric oxide synthase expression in the uterus and placenta of infected mice. In addition, higher levels of TNF-α were detected in serum samples from C57BL/6 mice compared with BALB/c mice. Accordingly, C57BL/6 mice presented with levels of 90% abortion compared with 50% in BALB/c mice on day 19 p.i. C57BL/6 iNOS(-/-) mice showed low placental parasite counts and high absorption rates, similar to wild type mice. The data suggest that the impaired pregnancy outcome due to T. gondii infection in C57BL/6 mice could be associated with a higher inflammatory response leading to cell apoptosis and necrosis of implantation sites compared with BALB/c mice, and this phenomenon was not due to inducible nitric oxide synthase expression in the decidua.


Assuntos
Decídua/enzimologia , Decídua/patologia , Óxido Nítrico Sintase Tipo II/biossíntese , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/patologia , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/patologia , Animais , Modelos Animais de Doenças , Feminino , Expressão Gênica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Placenta/imunologia , Placenta/parasitologia , Placenta/patologia , Gravidez , Complicações Infecciosas na Gravidez/mortalidade , Resultado da Gravidez , Toxoplasma/patogenicidade , Toxoplasmose Animal/mortalidade , Fator de Necrose Tumoral alfa/sangue , Útero/imunologia , Útero/parasitologia , Útero/patologia
16.
Vaccine ; 29(49): 9183-93, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22001880

RESUMO

ArtinM and Jacalin (JAC) are lectins from the jackfruit (Artocarpus integrifolia) that have important role in modulation of immune responses to pathogens. Neospora caninum is an Apicomplexa parasite that causes neuromuscular disease in dogs and reproductive disorders in cattle, with economic impact on the livestock industry. Hence, we evaluated the adjuvant effect of ArtinM and JAC in immunization of mice against neosporosis. Six C57BL/6 mouse groups were subcutaneously immunized three times at 2-week intervals with Neospora lysate antigen (NLA) associated with lectins (NLA+ArtinM and NLA+JAC), NLA, ArtinM and JAC alone, and PBS (infection control). Animals were challenged with lethal dose of Nc-1 isolate and evaluated for morbidity, mortality, specific antibody response, cytokine production by spleen cells, brain parasite burden and inflammation. Our results demonstrated that ArtinM was able to increase NLA immunogenicity, inducing the highest levels of specific total IgG and IgG2a/IgG1 ratio, ex vivo Th1 cytokine production, increased survival, the lowest brain parasite burden, along with the highest inflammation scores. In contrast, NLA+JAC immunized group showed intermediate survival, the highest brain parasite burden and the lowest inflammation scores. In conclusion, ArtinM presents stronger immunostimulatory and adjuvant effect than Jacalin in immunization of mice against neosporosis, by inducing a protective Th1-biased pro-inflammatory immune response and higher protection after parasite challenge.


Assuntos
Adjuvantes Imunológicos/farmacologia , Coccidiose/prevenção & controle , Lectinas de Ligação a Manose/farmacologia , Neospora/patogenicidade , Lectinas de Plantas/farmacologia , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Artocarpus/química , Encéfalo/parasitologia , Coccidiose/imunologia , Citocinas/imunologia , Feminino , Imunização , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lectinas de Ligação a Manose/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Carga Parasitária , Lectinas de Plantas/imunologia , Baço/citologia , Baço/imunologia
17.
Acta gastroenterol. latinoam ; 25(5): 269-76, 1995. tab, graf
Artigo em Espanhol | BINACIS | ID: bin-22919

RESUMO

Con el objetivo de comparar diferentes técnicas de diagnóstico de Helicobacter pylori, enfrentamos el cultivo bacteriológico con técnicas menos laboriosas, de fácil manipulación, rápidas y menos onerosas, como el test rápido de la ureasa, el frotis con coloración, el estudio histopatológico y la determinación de anticuerpos anti Helicobacter pylori de clase IgG. Se estudiaron en forma prospectiva 43 pacientes de consulta hospitalaria, con sintomatología gastroduodenal. Con signos endoscópicos de inflamación y/o úlcera gastroduodenal. Se tomaron biopsias de Antro, Fundus gástrico y Bulbo duodenal, procesadas de la siguiente manera: a los 43 pacientes, para cada localización se realizó estudio microbiológico (frotis con coloración de Gram y Azul de Metileno, y cultivo en medio selectivo) y estudio histopatológico con cortes coloreados con Hematoxilina - Eosina. En la muestra antral de 37 pacientes se realizó) el test rápido de la ureasa (Clotest, Lab. Delta Westlen). El estudio inmunológico de búsqueda de anticuerpos de clase IgG mediante una técnica inmunoenzimática se hizo en 40 pacientes. Obteniéndose una sensibilidad (S) y una especificidad (E) para el frotis con coloración de 100 por ciento y 76 por ciento respectivamente. Para la antomía patológica: S = 86 por ciento y E = 61 por ciento, el test de la ureasa S = 100 por ciento y E = 62.5 por ciento, anticuerpos anti Helicobacter S = 100 por ciento y E no calculable. Se tomó el cultivo microbiológico como técnica de referencia basándonos en que el aislamiento del germen y su identificación constituye el criterio de presencia y vitalidad del mismo. Siendo el frotis con coloración, la anatomía patológica y el test rápido de la ureasa técnicas de buena presunción diagnóstica de infección presente, rápidas y de bajo costo para nuestro medio. En cambio el estudio inmunológico es de elección para conocer la prevalencia de la infección dado que la misma es de curso lento y los anticuerpos están presentes por tiempo prolongado en los infectados incluso después del tratamiento. (AU)


Assuntos
Estudo Comparativo , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Mucosa Gástrica/microbiologia , Urease/metabolismo , Corantes Azur/diagnóstico , Ensaio de Imunoadsorção Enzimática , Endoscopia Gastrointestinal
18.
Acta gastroenterol. latinoam ; 25(5): 269-76, 1995. tab, graf
Artigo em Espanhol | LILACS | ID: lil-164075

RESUMO

Con el objetivo de comparar diferentes técnicas de diagnóstico de Helicobacter pylori, enfrentamos el cultivo bacteriológico con técnicas menos laboriosas, de fácil manipulación, rápidas y menos onerosas, como el test rápido de la ureasa, el frotis con coloración, el estudio histopatológico y la determinación de anticuerpos anti Helicobacter pylori de clase IgG. Se estudiaron en forma prospectiva 43 pacientes de consulta hospitalaria, con sintomatología gastroduodenal. Con signos endoscópicos de inflamación y/o úlcera gastroduodenal. Se tomaron biopsias de Antro, Fundus gástrico y Bulbo duodenal, procesadas de la siguiente manera: a los 43 pacientes, para cada localización se realizó estudio microbiológico (frotis con coloración de Gram y Azul de Metileno, y cultivo en medio selectivo) y estudio histopatológico con cortes coloreados con Hematoxilina - Eosina. En la muestra antral de 37 pacientes se realizó) el test rápido de la ureasa (Clotest, Lab. Delta Westlen). El estudio inmunológico de búsqueda de anticuerpos de clase IgG mediante una técnica inmunoenzimática se hizo en 40 pacientes. Obteniéndose una sensibilidad (S) y una especificidad (E) para el frotis con coloración de 100 por ciento y 76 por ciento respectivamente. Para la antomía patológica: S = 86 por ciento y E = 61 por ciento, el test de la ureasa S = 100 por ciento y E = 62.5 por ciento, anticuerpos anti Helicobacter S = 100 por ciento y E no calculable. Se tomó el cultivo microbiológico como técnica de referencia basándonos en que el aislamiento del germen y su identificación constituye el criterio de presencia y vitalidad del mismo. Siendo el frotis con coloración, la anatomía patológica y el test rápido de la ureasa técnicas de buena presunción diagnóstica de infección presente, rápidas y de bajo costo para nuestro medio. En cambio el estudio inmunológico es de elección para conocer la prevalencia de la infección dado que la misma es de curso lento y los anticuerpos están presentes por tiempo prolongado en los infectados incluso después del tratamiento.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Infecções por Helicobacter/diagnóstico , Corantes Azur , Endoscopia Gastrointestinal , Ensaio de Imunoadsorção Enzimática , Helicobacter pylori/isolamento & purificação , Mucosa Gástrica/microbiologia , Urease/metabolismo
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