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1.
Vet Pathol ; 58(6): 1075-1085, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34128432

RESUMO

Equid alphaherpesvirus 1 (EHV-1) causes myeloencephalopathy in horses and occasionally in non-equid species. Although mouse models have been developed to understand EHV-1 pathogenesis, few EHV-1 strains have been identified as highly neurovirulent to mice. The aim of this study was to evaluate the pathogenesis of 2 neurovirulent EHV-1 strains in mice, and to characterize the inflammatory cells and expression of chemokines and the apoptosis marker caspase-3 in the brain of infected mice. C57BL/6J mice were inoculated intranasally with EHV-1 strains A4/72 or A9/92 and evaluated on 1, 2, and 3 days post inoculation (DPI). EHV-1-infected mice showed severe neurological signs at 3 DPI. Ultrastructural analysis revealed numerous viral nucleocapsids and fewer enveloped virions within degenerated and necrotic neurons and in the surrounding neuropil. Histologically, at 3 DPI, there was severe diffuse neuronal degeneration and liquefactive necrosis, prominent microgliosis, and perivascular cuffing composed of CD3+ cells (T cells) and Iba-1+ cells (macrophages), mainly in the olfactory bulb and ventral portions of the brain. In these areas, moderate numbers of neuroglial cells expressed CCL5 and CCL2 chemokines. Numerous neurons, including those in less affected areas, were immunolabeled for cleaved caspase-3. In conclusion, neurovirulent EHV-1 strains induced a fulminant necrotizing lymphohistiocytic meningoencephalitis in mice, with microgliosis and expression of chemokines and caspase-3. This model will be useful for understanding the mechanisms underlying the extensive neuropathology induced by these viral infections.


Assuntos
Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Doenças dos Roedores , Animais , Encéfalo , Modelos Animais de Doenças , Infecções por Herpesviridae/veterinária , Cavalos , Camundongos , Camundongos Endogâmicos C57BL
2.
J Gen Virol ; 102(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33528354

RESUMO

Equine herpesvirus type 1 (EHV-1) is an emerging pathogen that causes encephalomyelitis in horses and non-equid species. Several aspects of the immune response in the central nervous system (CNS), mainly regarding the role of inflammatory mediators during EHV-1 encephalitis, remain unknown. Moreover, understanding the mechanisms underlying extensive neuropathology induced by viruses would be helpful to establish therapeutic strategies. Therefore, we aimed to evaluate some aspects of the innate immune response during highly neurovirulent EHV-1 infection. C57BL/6 mice infected intranasally with A4/72 and A9/92 EHV-1 strains developed a fulminant neurological disease at 3 days post-inoculation with high viral titres in the brain. These mice developed severe encephalitis with infiltration of monocytes and CD8+ T cells to the brain. The inflammatory infiltrate followed the detection of the chemokines CCL2, CCL3, CCL4, CCL5, CXCL2, CXCL9 and CXCL-10 in the brain. Notably, the levels of CCL3, CCL4, CCL5 and CXCL9 were higher in A4/72-infected mice, which presented higher numbers of inflammatory cells within the CNS. Pro-inflammatory cytokines, such as interleukins (ILs) IL-1α, IL-1ß, IL-6, IL-12ß, and tumour necrosis factor (TNF), were also detected in the CNS, and Toll-like receptor (TLR) TLR2, TLR3 and TLR9 genes were also upregulated within the brain of EHV-1-infected mice. However, no expression of interferon-γ (IFN-γ) and IL-12α, which are important for controlling the replication of other herpesviruses, was detected in EHV-1-infected mice. The results show that the activated innate immune mechanisms could not prevent EHV-1 replication within the CNS, but most likely contributed to the extensive neuropathology. The mouse model of viral encephalitis proposed here will also be useful to study the mechanisms underlying extensive neuropathology.


Assuntos
Encéfalo/imunologia , Encefalite Viral/imunologia , Infecções por Herpesviridae/imunologia , Herpesvirus Equídeo 1/imunologia , Herpesvirus Equídeo 1/patogenicidade , Animais , Encéfalo/metabolismo , Encéfalo/virologia , Quimiocinas/genética , Quimiocinas/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite Viral/virologia , Infecções por Herpesviridae/virologia , Imunidade Inata , Leucócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores Toll-Like/genética , Regulação para Cima , Carga Viral
3.
New Phytol ; 219(4): 1252-1262, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29767841

RESUMO

Wood properties influence the leaf life span (LL) of tree crowns. As lignin is an important component of wood and the water transport system, we investigated its relationship with embolism resistance and the LL of several tree species in a seasonally dry tropical ecosystem. We determined total lignin and the monomer contents of guaiacyl (G) and syringyl (S) and related them to wood traits and xylem vulnerability to embolism (Ψ50 ) for the most common species of the Brazilian semiarid, locally known as Caatinga. Leaf life span was negatively related to Ψ50 and positively related to S : G, which was negatively related to Ψ50 . This means that greater S : G increases LL by reducing Ψ50 . Lignin content was not correlated with any variable. We found two apparently unrelated axes of drought resistance. One axis, associated with lignin monomeric composition, increases LL in the dry season as a result of lower xylem embolism vulnerability. The other, associated with wood density and stem water content, helps leafless trees to withstand drought and allows them to resprout at the end of the dry season. The monomeric composition of lignin (S : G) is therefore an important functional wood attribute affecting several key functional aspects of tropical tree species in a semiarid climate.


Assuntos
Clima Desértico , Lignina/metabolismo , Folhas de Planta/fisiologia , Árvores/fisiologia , Clima Tropical , Xilema/fisiologia , Análise de Componente Principal , Madeira/fisiologia
4.
Pesqui. vet. bras ; 38(3): 444-449, mar. 2018. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-964461

RESUMO

Neospora caninum has been described as a parasite that sporadically causes reproductive problems in goats. Several aspects of the pathogenesis of neosporosis in naturally infected goats remain to be established. The aims of the present study were to characterize the placental lesions in goats naturally infected by N. caninum and to evaluate several diagnostic techniques for effective detection of this protozoan in the goat placenta. Some placentas in this study originated from abortion and stillbirth in which there were severe lesions. The lesions were characterized mainly by necrosis involving the mesenchyme of the chorionic villi and trophoblast cells often alongside mononuclear inflammation and in some cases with neutrophilic infiltration. N. caninum DNA was detected in these placentas, but parasite structures were not visualized through immunohistochemistry (IHC). However, five of 11 placentas from N. caninum-infected goats that gave birth to healthy kids had histological lesions characterized by mononuclear inflammation. Of these 11 placentas, N. caninum DNA was detected in seven, and N. caninum tachyzoites were detected in only one of these seven placentas using IHC. The present study demonstrates that severe lesions in the placenta are associated with abortion and stillbirth in caprine neosporosis and the placental alterations are likely involved in abortion pathogenesis. Moreover, the results highlight the importance of using more than one diagnostic technique for the detection of the protozoan in placentas because N. caninum cannot be reliably detected by histological and immunohistochemical tests.(AU)


Neospora caninum é descrito como um parasito que causa problemas reprodutivos esporádicos em cabras. Muitos aspectos da patogênese da neosporose em cabras naturalmente infectadas ainda precisam ser estabelecidos. Os objetivos deste trabalho foram caracterizar as lesões placentárias em cabras naturalmente infectadas por N. caninum e avaliar as técnicas diagnósticas para a detecção efetiva do protozoário na placenta. Algumas placentas deste estudo são originárias de abortos e natimortos, nas quais havia lesões graves. As lesões foram classificadas principalmente por necrose envolvendo o mesênquima das vilosidades coriônicas e células trofoblásticas, geralmente associadas a infiltrado inflamatório mononuclear e em alguns casos infiltrado neutrofílico. O DNA do N. caninum foi detectado nestas placentas, porém estruturas parasitárias não foram visualizadas na imuno-histoquímica (IHQ). Entretanto, cinco das onze placentas de cabras infectadas, que deram à luz a conceptos saudáveis, apresentaram lesões histológicas caracterizadas por infiltrado inflamatório mononuclear. Destas 11 placentas, foi detectado DNA de N. caninum em sete e taquizoítos foram encontrados em apenas uma por meio de imuno-histoquímica. O presente estudo demonstra que abortos e natimortos na espécie caprina, causados pelo N. caninum estão associados a lesões acentuadas nas placentas, sendo que as mesmas estão envolvidas na patogênese do aborto. Os resultados também ressaltam a importância do uso de mais de uma técnica diagnóstica para a detecção do protozoário em placentas, pois o N. caninum não pode ser confiavelmente detectado somente pelos exames de histopatologia e imuno-histoquímica.(AU)


Assuntos
Animais , Ruminantes/anatomia & histologia , Neospora/parasitologia , Aborto Animal/diagnóstico
5.
Pesqui. vet. bras ; 37(9): 977-983, Sept. 2017. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-895529

RESUMO

Recently, glutamine and ß-glucan have been demonstrated to play an important role in modulation of the immune system and in promoting intestinal health benefits. The aim of this study was to investigate the effect of this intervention on inflammatory responses and intestinal health in mice orally pretreated with soluble Saccharomyces cerevisiae derived 1,3/1,6-ß-glucan (80mg/kg) with or without glutamine (150mg/kg) and then challenged with cytarabine (Ara-C) (15mg/kg). Improvements in villi and crypts were not observed in the ß-glucan group. The intestinal morphometry in the glutamine group showed the best results. ß-glucan in combination with glutamine presented the highest values of IL-1ß and IL-10 and lowest values for leukocytes and INF-γ. Based on these results, combined ß-glucan and glutamine pretreatment reduced intestinal inflammation and improved the immune response after Ara-C challenge.(AU)


Recentemente, glutamina e ß-glucano têm demonstrado desempenhar um papel importante na modulação do sistema imune e na promoção de benefícios para a saúde intestinal. O objetivo deste estudo foi investigar o efeito dessa intervenção sobre as respostas inflamatórias e saúde intestinal de camundongos pré- tratados por via oral com 1,3/1,6-ß-glucano (80mg/kg) derivado de Saccharomyces cerevisiae com ou sem glutamina (150mg/kg) e posteriormente desafiados com citarabina (Ara-C) (15mg/kg). Melhoras em vilosidades e criptas não foram observadas no grupo de tratamento com ß-glucano. A morfometria intestinal no grupo de tratamento com glutamina apresentou os melhores resultados. O grupo em que foi utilizado ß-glucano em combinação com glutamina apresentou os maiores valores de IL-1ß e IL -10 e valores mais baixos para os leucócitos e INF-γ. Com base nestes resultados, o pré-tratamento de ß-glucano combinado com glutamina reduziu a inflamação intestinal e melhorou a resposta imune após o desafio com Ara-C.(AU)


Assuntos
Animais , Masculino , Camundongos , Citarabina , beta-Glucanas/uso terapêutico , Glutamina/uso terapêutico , Sistema Imunitário/efeitos dos fármacos , Mucosa Intestinal
6.
J Clin Periodontol ; 44(11): 1153-1163, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28800160

RESUMO

AIM: To evaluate the effects of physical training on inflammatory and behavioural parameters of Wistar rats with periodontal disease (PD). MATERIALS AND METHODS: Twenty four animals were distributed in a 2 × 2 factorial design (with and without exercise, with and without PD). Trained animals swimmed one hour daily during 8 weeks. PD was induced by ligature 14 days before the end of experiment, and in the last week, all animals were submitted to the Marble Burying Test. Histomorphometric analyses of the mandibles and expression of cytokines were conducted by Western blotting. We also evaluated the morphometry of hippocampal astrocytes using anti-glial fibrillary acidic protein antibody. RESULTS: Physical training attenuated bone loss and epithelial attachment loss levels of rats with PD. Trained animals with PD presented lower TNF-α expression in periodontal tissues while IL-10 was increased. TNF-α/IL-10 ratio was lower in trained animals with PD compared to those with induced periodontitis. PD increased anxiety-like behaviour, and physical training attenuated this parameter. Exercise increased the ramifications of hippocampal astrocytes in rats without PD. CONCLUSIONS: Exercise decreased anxiety behaviour, inflammatory proteins expression and bone loss in rats with PD.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Ansiedade/prevenção & controle , Periodontite/terapia , Condicionamento Físico Animal , Animais , Western Blotting , Citocinas/análise , Gengiva/química , Masculino , Periodontite/psicologia , Ratos , Ratos Wistar
7.
Pesqui. vet. bras ; 35(5): 466-469, May 2015. ilus
Artigo em Inglês | LILACS | ID: lil-759380

RESUMO

Trematodes belonging to the family Eucotylidae, including Tanaisia (Paratanaisia)bragai Santos, 1934are parasites of the kidney and ureter that affect several species of domestic and wild birds. Tanaisia bragai is considered a low pathogenic parasite, but high worm burdens may determine clinical complications, including signs of apathy, weight loss, diarrhea and death...


Os trematódeos da família Eucotylidae, incluindo Tanaisia (Paratanaisia)bragai Santos, 1934, são parasitos de rins e ureteres de várias espécies de aves domésticas e silvestres. Tanaisia bragai é considerada uma espécie pouco patogênica, mas que pode determinar complicações clínicas como apatia, perda de peso, diarreia e morte, quando em cargas parasitárias elevadas...


Assuntos
Animais , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/parasitologia , Trematódeos/parasitologia , Parasitologia/métodos , Carga Parasitária/veterinária , Contagem de Ovos de Parasitas/métodos , Contagem de Ovos de Parasitas/veterinária , Parasitos/parasitologia
8.
Pesqui. vet. bras ; 33(11): 1332-1338, Nov. 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-697879

RESUMO

Este estudo avaliou a participação de Neospora caninum em casos de abortos em bovinos provenientes de propriedades rurais da região sul de Minas Gerais por meio de análises histopatológicas, imuno-histoquímicas (IHQ) e pela reação em Cadeia de Polimerase (PCR). O material utilizado foi obtido de um estudo retrospectivo de casos de aborto recebidos pelo Setor de Patologia Veterinária da Universidade Federal de Lavras e de fetos necropsiados durante os anos de 2011 a 2013. De 60 fetos estudados, 30 (50%) tinham lesões microscópicas. Destes, 19 (63%) apresentaram lesões compatíveis com aborto por N. caninum, caracterizadas principalmente por encefalite não supurativa multifocal, necrose e gliose multifocal, assim como, miocardite e miosite não supurativa. Em 14 fetos chegou-se ao diagnóstico definitivo. Destes, cinco tiveram sua confirmação somente pela marcação IHQ e cinco foram positivos somente na PCR. Quatro fetos foram positivos tanto na IHQ quanto na PCR. Cinco fetos, provenientes do estudo retrospectivo apresentaram lesões compatíveis com N. caninum, mas a presença do protozoário não foi confirmada pela marcação IHQ. Os achados demonstram que o N. caninum é um importante agente associado ao aborto em bovinos na região sul de Minas Gerais. Para tanto, além das lesões microscópicas a associação entre a IHQ e a técnica de PCR foi essencial para a confirmação do diagnóstico.


The present study evaluates the participation of Neospora caninum in bovine abortions from farms in the southern region of Minas Gerais state, Brazil, through histopathological, immunohistochemical (IHQ) analysis and DNA detection by polymerase chain reaction (PCR). The material used in this study was obtained through retrospective study of bovine abortion cases received by the Setor de Patologia Veterinária da Universidade Federal de Lavras and by necropsies performed in fetuses from 2011 to 2013. From 60 fetuses studied, 30 (50%) had microscopic lesions; 19 (63%) of them had histologic lesions compatible with N. caninum abortion, characterized by multifocal non-suppurative encephalitis, necrosis and gliosis in the central nervous system and multifocal nonsuppurative myocarditis and myositis. From the 19 fetuses with protozoa lesions in 14 the final diagnosis was performed; five were confirmated only by IHQ staining and five were positive only by PCR. Four fetuses were positive in IHC and in PCR. In five fetuses from the retrospective study lesions compatible with N. caninum were seen, but the presence of the protozoan was not confirmed by IHQ labeling. The findings demonstrate that N. caninum is an important agent associated with abortion in cattle from Minas Gerais. Therefore, beyond the microscopic lesions association between IHC and PCR was essential to confirm the diagnosis.


Assuntos
Animais , Feminino , Gravidez , Bovinos , Aborto Animal/fisiopatologia , Coccidiose/veterinária , Infecções Protozoárias em Animais/epidemiologia , Neospora/patogenicidade , Estudos Retrospectivos
9.
Vet Parasitol ; 196(3-4): 327-33, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23537945

RESUMO

Neospora caninum is a protozoan which can cause abortions in caprines. However, information regarding the humoral immune response and the occurrence of reproductive disorders is scarce. This is the first study in which the kinetics of antibodies is studied in pregnant goats naturally infected by N. caninum, as well as their respective conceptuses. The subclasses of IgG (IgG1 and IgG2) were also evaluated in pregnant goats. Reproductive problems related to neosporosis (abortion and stillbirth) occurred in 15.38% of the goats. There was a statistically significant association between the increased titres of maternal IgG in the second half of the gestational period with the occurrence of endogenous transplacental transmission. The rate of congenital transmission was 77%. During the gestational period of the seropositive goats, there was mainly a predominance of the subclass IgG2, although mixed patterns of IgG2-IgG1 and the IgG1 pattern were also observed. These results indicate that N. caninum is responsible for the occurrence of important alterations in the humoral immune response of naturally infected goats, and is also a potential causative agent for reproductive disorders in goats. The high proportion of infected conceptuses reinforces the suggestion that congenital infection is one of the main routes of parasite transmission in goats.


Assuntos
Anticorpos Antiprotozoários/metabolismo , Coccidiose/veterinária , Doenças das Cabras/parasitologia , Imunoglobulina G/metabolismo , Neospora/imunologia , Feto Abortado/parasitologia , Aborto Animal/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Coccidiose/sangue , Coccidiose/imunologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Doenças das Cabras/imunologia , Cabras , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Gravidez , Complicações Parasitárias na Gravidez/sangue , Complicações Parasitárias na Gravidez/imunologia , Complicações Parasitárias na Gravidez/parasitologia , Complicações Parasitárias na Gravidez/veterinária , Natimorto/veterinária
10.
Korean J Parasitol ; 50(1): 63-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22451736

RESUMO

Congenital Neospora caninum infection was diagnosed in two Saanen goat kids from two distinct herds with a history of abortion and weak newborn goat kids in the Southern region of the State of Minas Gerais, Brazil. The first kid was weak at birth, had difficulty to rise and was unable to nurse. Gross lesions of porencephaly and hydrocephalus ex vacuo were seen. Multifocal necrosis, gliosis and non-supurative encephalitis were observed in the brain. Several parasitic cysts with a thick wall that reacted strongly only with polyclonal antiserum to Neospora caninum were seen in the cerebral cortex, brain stem and cerebellum. The second kid was born from a Neospora caninum seropositive mother that aborted in the last pregnancy. It was born without clinical signs. The diagnosis of neosporosis was based on antibody titer of 1:800 to N. caninum by indirect fluorescence antibody test obtained from blood collected before the goat kid ingested the colostrum and Neospora caninum DNA was detected by polymerase chain reaction and sequenced from placenta. This is the first report of neosporosis in goats in the southeast region of Brazil.


Assuntos
Coccidiose/veterinária , Doenças das Cabras/parasitologia , Neospora/isolamento & purificação , Animais , Anticorpos Antiprotozoários/imunologia , Brasil , Coccidiose/congênito , Coccidiose/imunologia , Coccidiose/parasitologia , Feminino , Doenças das Cabras/congênito , Doenças das Cabras/imunologia , Cabras , Dados de Sequência Molecular , Neospora/genética , Neospora/imunologia , Neospora/fisiologia , Gravidez
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