RESUMO
Sarcocistys -associated menigoencephalitis is virtually an unrecognized cause of neurological disease in chickens. An undescribed species of Sarcocystis cause fatal infection in two backyard chickens in the Midwest of Brazil. Infected chickens presented anorexia, weight loss, incoordination, ataxia and opisthotonos. Yellow necrotic foci in the gray and white matter of the telencephalon were the main gross lesion. Microscopically, necrotizing granulomatous and heterophilic meningoencephalitis with intralesional Sarcocystis -like schizonts and mezoites were observed in the central nervous system. Molecular analysis of frozen brain samples of the two chickens was identical and the protozoan was named Sarcocystis sp. Chicken-2016-DF-BR. Complete nested PCR- sequence of Sarcocystis sp. Chicken-2016-DF-BR was equally similar to Sarcocystis anasi (EU553477) and Sarcocystis albifronsi (EU502868). This is the first report of Sarcocistys -associated meningoencephalitis with molecular characterization in backyard chickens.
Assuntos
Galinhas , Meningoencefalite/veterinária , Doenças das Aves Domésticas/diagnóstico , Sarcocystis/classificação , Animais , Encéfalo/parasitologia , Encéfalo/patologia , Brasil , Feminino , Masculino , Meningoencefalite/diagnóstico , Meningoencefalite/parasitologia , Meningoencefalite/patologia , Necrose/diagnóstico , Necrose/parasitologia , Necrose/patologia , Necrose/veterinária , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/patologia , Sarcocystis/fisiologiaRESUMO
Loxocelism is a neglected medical problem that depends on its severity, can cause a cutaneous or viscero-cutaneous syndrome. This syndrome is characterized by hemostatic effects and necrosis, and the severity of the loxoscelism depends on the amount of venom injected, the zone of inoculation, and the species. In the Chihuahuan desert, the most abundant species is L. apachea. Its venom and biological effects are understudied, including neurological effects. Thus, our aim is to explore the effect of this regional species of medical interest in the United States-Mexico border community, using rat blood and central nervous system (CNS), particularly, two brain structures involved in brain homeostasis, Area postrema (AP) and Choroid plexus (PC). L. apachea specimens were collected and venom was obtained. Different venom concentrations (0, 0.178 and 0.87 µg/g) were inoculated into Sprague-Dawley rats (intraperitoneal injection). Subsequently, blood was extracted and stained with Wright staining; coronal sections of AP were obtained and stained with Hematoxylin-Eosin (HE) staining and laminin γ immunolabelling, the same was done with CP sections. Blood, AP and CP were observed under the microscope and abnormalities in erythrocytes and fluctuation in leukocyte types were described and quantified in blood. Capillaries were also quantified in AP and damage was described in CP. L. apachea venom produced a segmented neutrophil increment (neutrophilia), lymphocyte diminishment (leukopenia) and erythrocytes presented membrane abnormalities (acanthocytosis). Extravasated erythrocytes were observed in HE stained sections from both, AP and CP, which suggest that near to this section a hemorrhage is present; through immunohistofluorescence, a diminishment of laminin γ was observed in AP endothelial cells and in CP ependymal cells when these structures were exposed to L. apachea venom. In conclusion, L. apachea venom produced leukopenia, netrophilia and acanthocytosis in rat peripheral blood, and also generated hemorrhages on AP and CP through degradation of laminin γ.
Assuntos
Abetalipoproteinemia/parasitologia , Área Postrema/parasitologia , Lesões Encefálicas/parasitologia , Plexo Corióideo/parasitologia , Diester Fosfórico Hidrolases/toxicidade , Venenos de Aranha/toxicidade , Animais , Aracnídeos/parasitologia , Células Endoteliais/parasitologia , Eritrócitos/parasitologia , Hemorragia/parasitologia , Leucócitos/parasitologia , Linfócitos/parasitologia , México , Necrose/parasitologia , Ratos , Ratos Sprague-Dawley , Pele/parasitologia , Aranhas/patogenicidadeRESUMO
We evaluated the importance of neutrophils in the development of chronic lesions caused by L. Viannia spp. using the hamster as experimental model of American Cutaneous Leishmaniasis (ACL). Neutrophils infiltrated the lesion within the first six hours post-infection. Inhibition of this early infiltration using a polyclonal antibody or cyclophosphamide was associated with transient parasite control but the protective effect vanished when lesions became clinically apparent. At lesion onset (approximately 10 days p.i.), there was an increased proportion of both uninfected and infected macrophages, and subsequently a second wave of neutrophils infiltrated the lesion (after 19 days p.i.) This second neutrophil infiltration was associated with lesion necrosis and ulceration (R2 = 0.75) and maximum parasite burden. Intradermal delivery of N-formylmethionyl-leucyl-phenylalanine (fMLP), aimed to increase neutrophil infiltration, resulted in larger lesions with marked necrosis and higher parasite burden than in mock treated groups (p<0.001 each). In contrast, reduced neutrophil infiltration via cyclophosphamide-mediated depletion led to more benign lesions and lower parasite loads compared to controls (p<0.001 each). Neutrophils of the second wave expressed significantly lower GM-CSF, reactive oxygen species and nitric oxide than those of the first wave, suggesting that they had less efficient anti-leishmania activity. However, there was increased inflammatory cytokines and expression of neutrophil proteases (myeloperoxidase, cathepsin G and elastase) in lesions during the second wave of neutrophil infiltration compared with the levels reached during the first wave (6h p.i.). This suggests that augmented neutrophil proteases and inflammatory cytokines during the secondary wave of neutrophils could contribute to skin inflammation, ulceration and necrosis in ACL. The overall results indicate that neutrophils were unable to clear the infection in this model, and that the second wave of neutrophils played an important role in the severity of ACL.
Assuntos
Inflamação/sangue , Leishmaniose Cutânea/sangue , Necrose/sangue , Infiltração de Neutrófilos , Animais , Cricetinae , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/parasitologia , Inflamação/fisiopatologia , Leishmania/patogenicidade , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/fisiopatologia , Macrófagos/patologia , Necrose/parasitologia , Necrose/fisiopatologia , Neutrófilos/patologia , Óxido Nítrico/metabolismo , Carga Parasitária , Espécies Reativas de Oxigênio/metabolismo , Estados UnidosRESUMO
Leishmaniasis are a neglected group of emerging diseases that have been found in 98 countries and are caused by protozoa of the genus Leishmania. The therapy for leishmaniasis causes several side effects and leads to drug-resistant strains. Natural products from plants have exhibited activities against Leishmania in various experimental models. Physalis angulata is a widely used plant in popular medicine, and in the literature it has well-documented leishmanicidal activity. However, its mechanism of action is still unknown. Thus, this study aims to evaluate the mechanism driving the leishmanicidal activity of an aqueous extract of P. angulata root (AEPa). AEPa was effective against both promastigotes and intracellular amastigote forms of Leishmania amazonensis. This effect was mediated by an increase of reactive oxygen species (ROS), but not of nitric oxide (NO). The increased production of ROS induces cell death by phenotypes seems by apoptosis cell death in Leishmania, but not autophagy or necrosis. In addition, morphological analysis of macrophages showed that AEPa induced a high number of cytoplasmic projections, increased the volume of cytoplasm and number of vacuoles, caused cytoskeleton alterations and resulted in high spreading ability. AEPa also promoted superoxide anion (O2(-)) production in both uninfected macrophages and those infected with Leishmania. Therefore, these results revealed that AEPa causes cell death by phenotypes seems by apoptosis cell death in L. amazonensis and modulates macrophage activation through morphofunctional alterations and O2(-) generation to induce Leishmania death.
Assuntos
Leishmania/fisiologia , Macrófagos Peritoneais/efeitos dos fármacos , Physalis/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia , Leishmania/efeitos dos fármacos , Leishmania/imunologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/parasitologia , Macrófagos Peritoneais/ultraestrutura , Camundongos , Necrose/parasitologia , FitoterapiaRESUMO
Clostridium perfringens is an important pathogen in both human and veterinary medicine. Necrotic enteritis (NE) is the most clinically dramatic bacterial enteric disease of poultry induced by C. perfringens. The pathogenicity of this bacterium is associated with the production of extracellular toxins produced by some of its strains, such as beta2 toxin. The exact role of beta2 toxin in NE pathogenesis is still controversial. In the present study, C. perfringens isolates from healthy and diseased poultry flocks from different parts of Iran were analyzed by PCR assay to determine the presence of all variants of the beta2 toxin gene (cpb2). The products of two positive cpb2 PCR reactions were sequenced, compared to each other and to the cpb2 sequences published in GenBank (by multiple alignment and phylogenetic analysis). The current work represents the first study of cpb2 in poultry C. perfringens isolates in Asia, and reports the highest percentage of cpb2-positive isolates in both apparently healthy chickens (97.7 percent) and those afflicted with NE (94.4 percent). The sequenced isolates were classified as atypical. This study did not show a direct correlation between NE occurrence and cpb2 presence.(AU)