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1.
Parasitology ; : 1-10, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38629122

RESUMO

Haemogregarine (Apicomplexa: Adeleorina) parasites are considered to be the most common and widespread haemoparasites in reptiles. The genus Hepatozoon (Apicomplexa: Adeleorina: Hepatozoidae) can be found parasitizing a broad range of species and, in reptiles, they infect mainly peripheral blood erythrocytes. The present study detected and characterized a haemogregarine isolated from the lizard species, Ameiva ameiva, collected from the municipality of Capanema, Pará state, north Brazil. Blood smears and imprints from lungs, brain, heart, kidney, liver, bone marrow and spleen were observed using light microscopy and the parasite was genetically identified by molecular analysis. Morphological, morphometric and molecular data were obtained. Parasite gamonts were found in 49.5% (55/111) of the blood smears from A. ameiva, and were characterized as oval, averaging 12.0 ± 0.8 × 5.9 ± 0.6 µm2 in size, which displaced the nuclei of parasitized monocytes laterally. Parasite forms resembling immature gamonts were observed in the spleen and bone marrow of the lizards. Furthermore, phylogenetic analyses of 18S rRNA sequences did not reveal gene similarity with other Hepatozoon spp. sequences from reptiles. Thus, morphological and molecular analyses have identified a new species of Hepatozoon parasite, Hepatozoon lainsoni sp. nov., which infects monocytes of the A. ameiva lizard.

2.
Front Immunol ; 14: 1239572, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37711609

RESUMO

Normally, the host immunological response to viral infection is coordinated to restore homeostasis and protect the individual from possible tissue damage. The two major approaches are adopted by the host to deal with the pathogen: resistance or tolerance. The nature of the responses often differs between species and between individuals of the same species. Resistance includes innate and adaptive immune responses to control virus replication. Disease tolerance relies on the immune response allowing the coexistence of infections in the host with minimal or no clinical signs, while maintaining sufficient viral replication for transmission. Here, we compared the virome of bats, rodents and migratory birds and the molecular mechanisms underlying symptomatic and asymptomatic disease progression. We also explore the influence of the host physiology and environmental influences on RNA virus expression and how it impacts on the whole brain transcriptome of seemingly healthy semipalmated sandpiper (Calidris pusilla) and spotted sandpiper (Actitis macularius). Three time points throughout the year were selected to understand the importance of longitudinal surveys in the characterization of the virome. We finally revisited evidence that upstream and downstream regulation of the inflammatory response is, respectively, associated with resistance and tolerance to viral infections.


Assuntos
Quirópteros , Viroses , Animais , Roedores , Aves , Tolerância Imunológica
3.
Front Cell Infect Microbiol ; 12: 812152, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372100

RESUMO

Ocular infection with Toxoplasma gondii causes toxoplasmosis in mice. However, following ocular infection with tachyzoites, the cause of the accompanying progressive changes in hippocampal-dependent tasks, and their relationship with the morphology and number of microglia, is less well understood. Here, in 6-month-old, female BALB/c mice, 5 µl of a suspension containing 48.5 × 106 tachyzoites/ml was introduced into the conjunctival sac; control received an equal volume of saline. Before and after instillation, all mice were subject to an olfactory discrimination (OD) test, using predator (cat) feces, and to an open-field (OF) task. After the behavioral tests, the animals were culled at either 22 or 44 days post-instillation (dpi), and the brains and retinas were dissected and processed for immunohistochemistry. The total number of Iba-1-immunolabeled microglia in the molecular layer of the dentate gyrus was estimated, and three-dimensional reconstructions of the cells were evaluated. Immobility was increased in the infected group at 12, 22, and 43 dpi, but the greatest immobility was observed at 22 dpi and was associated with reduced line crossing in the OF and distance traveled. In the OD test, infected animals spent more time in the compartment with feline fecal material at 14 and at 43 dpi. No OD changes were observed in the control group. The number of microglia was increased at 22 dpi but returned to control levels by 44 dpi. These changes were associated with the differentiation of T. gondii tachyzoites into bradyzoite-enclosed cysts within the brain and retina. Thus, infection of mice with T. gondii alters exploratory behavior, gives rise to a loss in predator's odor avoidance from 2 weeks after infection, increased microglia number, and altered their morphology in the molecular layer of the dentate gyrus.


Assuntos
Toxoplasma , Toxoplasmose Animal , Animais , Gatos , Túnica Conjuntiva/patologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Neuropatologia , Toxoplasmose Animal/patologia
4.
Front Cell Neurosci ; 15: 749595, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744633

RESUMO

The COVID-19 pandemic imposed a series of behavioral changes that resulted in increased social isolation and a more sedentary life for many across all age groups, but, above all, for the elderly population who are the most vulnerable to infections and chronic neurodegenerative diseases. Systemic inflammatory responses are known to accelerate neurodegenerative disease progression, which leads to permanent damage, loss of brain function, and the loss of autonomy for many aged people. During the COVID-19 pandemic, a spectrum of inflammatory responses was generated in affected individuals, and it is expected that the elderly patients with chronic neurodegenerative diseases who survived SARSCoV-2 infection, it will be found, sooner or later, that there is a worsening of their neurodegenerative conditions. Using mouse prion disease as a model for chronic neurodegeneration, we review the effects of social isolation, sedentary living, and viral infection on the disease progression with a focus on sickness behavior and on the responses of microglia and astrocytes. Focusing on aging, we discuss the cellular and molecular mechanisms related to immunosenescence in chronic neurodegenerative diseases and how infections may accelerate their progression.

5.
Brain Sci ; 11(8)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34439628

RESUMO

Microglia influence pathological progression in neurological diseases, reacting to insults by expressing multiple morphofunctional phenotypes. However, the complete morphological spectrum of reactive microglia, as revealed by three-dimensional microscopic reconstruction, has not been detailed in virus limbic encephalitis. Here, using an anatomical series of brain sections, we expanded on an earlier Piry arbovirus encephalitis study to include CA1/CA2 and assessed the morphological response of homeostatic and reactive microglia at eight days post-infection. Hierarchical cluster and linear discriminant function analyses of multimodal morphometric features distinguished microglial morphology between infected animals and controls. For a broad representation of the spectrum of microglial morphology in each defined cluster, we chose representative cells of homeostatic and reactive microglia, using the sum of the distances of each cell in relation to all the others. Based on multivariate analysis, reactive microglia of infected animals showed more complex trees and thicker branches, covering a larger volume of tissue than in control animals. This approach offers a reliable representation of microglia dispersion in the Euclidean space, revealing the morphological kaleidoscope of surveillant and reactive microglia morphotypes. Because form precedes function in nature, our findings offer a starting point for research using integrative methods to understand microglia form and function.

6.
Front Immunol ; 12: 683026, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220831

RESUMO

Microglial immunosurveillance of the brain parenchyma to detect local perturbations in homeostasis, in all species, results in the adoption of a spectrum of morphological changes that reflect functional adaptations. Here, we review the contribution of these changes in microglia morphology in distantly related species, in homeostatic and non-homeostatic conditions, with three principal goals (1): to review the phylogenetic influences on the morphological diversity of microglia during homeostasis (2); to explore the impact of homeostatic perturbations (Dengue virus challenge) in distantly related species (Mus musculus and Callithrix penicillata) as a proxy for the differential immune response in small and large brains; and (3) to examine the influences of environmental enrichment and aging on the plasticity of the microglial morphological response following an immunological challenge (neurotropic arbovirus infection). Our findings reveal that the differences in microglia morphology across distantly related species under homeostatic condition cannot be attributed to the phylogenetic origin of the species. However, large and small brains, under similar non-homeostatic conditions, display differential microglial morphological responses, and we argue that age and environment interact to affect the microglia morphology after an immunological challenge; in particular, mice living in an enriched environment exhibit a more efficient immune response to the virus resulting in earlier removal of the virus and earlier return to the homeostatic morphological phenotype of microglia than it is observed in sedentary mice.


Assuntos
Microglia/citologia , Animais , Biomarcadores , Encéfalo/anatomia & histologia , Encéfalo/citologia , Encéfalo/fisiologia , Forma Celular , Quirópteros , Cognição , Metabolismo Energético , Meio Ambiente , Homeostase , Humanos , Camundongos , Microglia/fisiologia , Tamanho do Órgão , Filogenia , Desempenho Psicomotor , Especificidade da Espécie
7.
Oxid Med Cell Longev ; 2016: 3974648, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28003864

RESUMO

We investigated possible interaction between an arbovirus infection and the ME7 induced mice prion disease. C57BL/6, females, 6-week-old, were submitted to a bilateral intrahippocampal injection of ME7 prion strain (ME7) or normal brain homogenate (NBH). After injections, animals were organized into two groups: NBH (n = 26) and ME7 (n = 29). At 15th week after injections (wpi), animals were challenged intranasally with a suspension of Piry arbovirus 0.001% or with NBH. Behavioral changes in ME7 animals appeared in burrowing activity at 14 wpi. Hyperactivity on open field test, errors on rod bridge, and time reduction in inverted screen were detected at 15th, 19th, and 20th wpi respectively. Burrowing was more sensitive to earlier hippocampus dysfunction. However, Piry-infection did not significantly affect the already ongoing burrowing decline in the ME7-treated mice. After behavioral tests, brains were processed for IBA1, protease-resistant form of PrP, and Piry virus antigens. Although virus infection in isolation did not change the number of microglia in CA1, virus infection in prion diseased mice (at 17th wpi) induced changes in number and morphology of microglia in a laminar-dependent way. We suggest that virus infection exacerbates microglial inflammatory response to a greater degree in prion-infected mice, and this is not necessarily correlated with hippocampal-dependent behavioral deficits.


Assuntos
Arbovírus/patogenicidade , Região CA1 Hipocampal/virologia , Coinfecção , Encefalite por Arbovirus/complicações , Microglia/virologia , Doenças Priônicas/complicações , Animais , Antígenos Virais/imunologia , Arbovírus/imunologia , Comportamento Animal , Região CA1 Hipocampal/imunologia , Região CA1 Hipocampal/patologia , Região CA1 Hipocampal/fisiopatologia , Proteínas de Ligação ao Cálcio/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Encefalite por Arbovirus/imunologia , Encefalite por Arbovirus/patologia , Encefalite por Arbovirus/psicologia , Feminino , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microglia/imunologia , Microglia/patologia , Atividade Motora , Degeneração Neural , Doenças Priônicas/patologia , Doenças Priônicas/psicologia , Fatores de Tempo
8.
Rev. bras. parasitol. vet ; 25(4): 429-434, Sept.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-830033

RESUMO

Abstract This study reports on Kudoa spp. (Myxozoa, Multivalvulida) from the fish species Lutjanus analis, Bagre marinus, Aspistor luniscutis and Lutjanus jocu, which were caught in Aracaju, state of Sergipe, Brazil. The parasites formed oval plasmodia around the esophagus of L. analis, and elongated plasmodia inside the skeletal muscle of B. marinus, A. luniscutis and L. jocu. Host myoliquefaction was not observed in all the cases studied. The current study provides a morphological and morphometric description of each parasite as well as a comparison with all the species described worldwide. Lack of molecular data impaired specific identification of the parasites. The importance of these parasites is discussed and the need for further studies on infections in Brazilian fish is emphasized because of the high economic impact of some Kudoa species which cause liquefaction in hosts’ muscles and render these fish unsuitable for consumption.


Resumo Este estudo relata Kudoa spp. (Myxozoa, Multivalvulida) de espécies de peixes Lutjanus analis, Bagre marinus, Aspistor luniscutis e Lutjanus jocu que foram capturados na costa litorânea de Aracaju, Estado de Sergipe, Brasil. Os parasitas formavam plasmódios ovais rodeando o esófago em L. analis, enquanto que nas espécies B. marinus, A. luniscutis e L. jocu formavam plasmódios alongados no interior das fibras musculares. Fenômenos de liquefação do músculo do hospedeiro não foram observados. O presente estudo proporciona uma descrição morfológica e morfométrica de cada parasita, sendo feita uma comparação com todas as espécies conhecidas em todo mundo. A inexistência de dados moleculares prejudica a identificação específica dos parasitas. A importância destes parasitas é discutida e a necessidade de mais estudos relacionados a infecções em peixes brasileiros é enfatizada por causa do alto impacto econômico de algumas espécies de Kudoa que causam liquefação nos músculos dos hospedeiros e tornam estes peixes impróprios para consumo.


Assuntos
Animais , Doenças Parasitárias em Animais/parasitologia , Perciformes/parasitologia , Doenças dos Peixes/parasitologia , Filogenia , Brasil , Myxozoa
9.
Rev Bras Parasitol Vet ; 25(4): 429-434, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27737370

RESUMO

This study reports on Kudoa spp. (Myxozoa, Multivalvulida) from the fish species Lutjanus analis, Bagre marinus, Aspistor luniscutis and Lutjanus jocu, which were caught in Aracaju, state of Sergipe, Brazil. The parasites formed oval plasmodia around the esophagus of L. analis, and elongated plasmodia inside the skeletal muscle of B. marinus, A. luniscutis and L. jocu. Host myoliquefaction was not observed in all the cases studied. The current study provides a morphological and morphometric description of each parasite as well as a comparison with all the species described worldwide. Lack of molecular data impaired specific identification of the parasites. The importance of these parasites is discussed and the need for further studies on infections in Brazilian fish is emphasized because of the high economic impact of some Kudoa species which cause liquefaction in hosts' muscles and render these fish unsuitable for consumption.


Assuntos
Doenças dos Peixes/parasitologia , Doenças Parasitárias em Animais/parasitologia , Perciformes/parasitologia , Animais , Brasil , Myxozoa , Filogenia
10.
Neuropathology ; 36(1): 3-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26303046

RESUMO

Severe dengue disease is often associated with long-term neurological impairments, but it is unclear what mechanisms are associated with neurological sequelae. Previously, we demonstrated antibody-enhanced dengue disease (ADE) dengue in an immunocompetent mouse model with a dengue virus 2 (DENV2) antibody injection followed by DENV3 virus infection. Here we migrated this ADE model to Callithrix penicillata. To mimic human multiple infections of endemic zones where abundant vectors and multiple serotypes co-exist, three animals received weekly subcutaneous injections of DENV3 (genotype III)-infected supernatant of C6/36 cell cultures, followed 24 h later by anti-DENV2 antibody for 12 weeks. There were six control animals, two of which received weekly anti-DENV2 antibodies, and four further animals received no injections. After multiple infections, brain, liver, and spleen samples were collected and tissue was immunolabeled for DENV3 antigens, ionized calcium binding adapter molecule 1, Ki-67, TNFα. There were marked morphological changes in the microglial population of ADE monkeys characterized by more highly ramified microglial processes, higher numbers of trees and larger surface areas. These changes were associated with intense TNFα-positive immunolabeling. It is unclear why ADE should generate such microglial activation given that IgG does not cross the blood-brain barrier, but this study reveals that in ADE dengue therapy targeting the CNS host response is likely to be important.


Assuntos
Sistema Nervoso Central/patologia , Dengue/patologia , Inflamação/patologia , Animais , Anticorpos Antivirais/toxicidade , Barreira Hematoencefálica/patologia , Callithrix , Vírus da Dengue/imunologia , Hipocampo/patologia , Imuno-Histoquímica , Microglia/patologia , Fator de Necrose Tumoral alfa/metabolismo
11.
Eur J Neurosci ; 42(4): 2036-50, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25980955

RESUMO

Many RNA virus CNS infections cause neurological disease. Because Piry virus has a limited human pathogenicity and exercise reduces activation of microglia in aged mice, possible influences of environment and aging on microglial morphology and behavior in mice sublethal encephalitis were investigated. Female albino Swiss mice were raised either in standard (S) or in enriched (EE) cages from age 2 to 6 months (young - Y), or from 2 to 16 months (aged - A). After behavioral tests, mice nostrils were instilled with Piry-virus-infected or with normal brain homogenates. Brain sections were immunolabeled for virus antigens or microglia at 8 days post-infection (dpi), when behavioral changes became apparent, and at 20 and 40 dpi, after additional behavioral testing. Young infected mice from standard (SYPy) and enriched (EYPy) groups showed similar transient impairment in burrowing activity and olfactory discrimination, whereas aged infected mice from both environments (EAPy, SAPy) showed permanent reduction in both tasks. The beneficial effects of an enriched environment were smaller in aged than in young mice. Six-hundred and forty microglial cells, 80 from each group were reconstructed. An unbiased, stereological sampling approach and multivariate statistical analysis were used to search for microglial morphological families. This procedure allowed distinguishing between microglial morphology of infected and control subjects. More severe virus-associated microglial changes were observed in young than in aged mice, and EYPy seem to recover microglial homeostatic morphology earlier than SYPy . Because Piry-virus encephalitis outcomes were more severe in aged mice, it is suggested that the reduced inflammatory response in those individuals may aggravate encephalitis outcomes.


Assuntos
Envelhecimento , Encéfalo/patologia , Encefalite Viral/patologia , Encefalite Viral/terapia , Meio Ambiente , Microglia/patologia , Análise de Variância , Animais , Complexo CD3/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Modelos Animais de Doenças , Encefalite Viral/fisiopatologia , Comportamento Exploratório , Feminino , Imageamento Tridimensional , Memória/fisiologia , Camundongos , Proteínas dos Microfilamentos/metabolismo , Rhabdoviridae/patogenicidade , Olfato/fisiologia , Fatores de Tempo
12.
PLoS One ; 9(8): e105231, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25137137

RESUMO

Pleomorphic adenoma is the most common salivary gland neoplasm, and it can be locally invasive, despite its slow growth. This study aimed to establish a novel cell line (AP-1) derived from a human pleomorphic adenoma sample to better understand local invasiveness of this tumor. AP-1 cell line was characterized by cell growth analysis, expression of epithelial and myoepithelial markers by immunofluorescence, electron microscopy, 3D cell culture assays, cytogenetic features and transcriptomic study. Expression of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) was also analyzed by immunofluorescence and zymography. Furthermore, epithelial and myoepithelial markers, MMPs and TIMPs were studied in the tumor that originated the cell line. AP-1 cells showed neoplastic epithelial and myoepithelial markers, such as cytokeratins, vimentin, S100 protein and smooth-muscle actin. These molecules were also found in vivo, in the tumor that originated the cell line. MMPs and TIMPs were observed in vivo and in AP-1 cells. Growth curve showed that AP-1 exhibited a doubling time of 3.342 days. AP-1 cells grown inside Matrigel recapitulated tumor architecture. Different numerical and structural chromosomal anomalies were visualized in cytogenetic analysis. Transcriptomic analysis addressed expression of 7 target genes (VIM, TIMP2, MMP2, MMP9, TIMP1, ACTA2 e PLAG1). Results were compared to transcriptomic profile of non-neoplastic salivary gland cells (HSG). Only MMP9 was not expressed in both libraries, and VIM was expressed solely in AP-1 library. The major difference regarding gene expression level between AP-1 and HSG samples occurred for MMP2. This gene was 184 times more expressed in AP-1 cells. Our findings suggest that AP-1 cell line could be a useful model for further studies on pleomorphic adenoma biology.


Assuntos
Adenoma Pleomorfo/patologia , Linhagem Celular Tumoral/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias das Glândulas Salivares/patologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Adulto , Biomarcadores Tumorais/metabolismo , Aberrações Cromossômicas , Análise Mutacional de DNA , Humanos , Masculino , Transcriptoma
13.
Parasitology ; 141(8): 1052-63, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24717447

RESUMO

In the present study, we assessed morphological changes and cytokine production after in vitro interaction with causative agents of American cutaneous leishmaniasis and compared the microglia and macrophage immune responses. Cultures of microglia and macrophages infected with stationary-phase promastigotes of Leishmania (Viannia) shawi, Leishmania (Viannia) braziliensis or Leishmania (Leishmania) amazonensis were evaluated 24, 48 and 72 h after interaction. Macrophages only presented the classical phagocytic process while microglia also displayed large cytoplasmic projections similar to the ruffles described in macropinocytosis. In the macrophage cultures, the percentage of infected cells increased over time, in a fashion that was dependent on the parasite species. In contrast, in microglial cells as the culture time progressed, there was a significant reduction in the percentage of infected cells independent of parasite species. Measurements of cytokines in macrophage cultures 48 h after interactions revealed distinct expression patterns for different parasites, whereas in microglial cultures they were similar for all Leishmania tested species. Taken together, our results suggest that microglia may have a higher phagocytic ability and cytotoxic potential than macrophages for all investigated species. The robust response of microglia against all parasite species may suggest microglia have an important role in the defence against cerebral leishmaniasis.


Assuntos
Citocinas/metabolismo , Leishmania/fisiologia , Leishmaniose/imunologia , Macrófagos Peritoneais/imunologia , Microglia/imunologia , Animais , Sobrevivência Celular , Células Cultivadas , Feminino , Leishmaniose/parasitologia , Macrófagos Peritoneais/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Microglia/ultraestrutura , Óxido Nítrico/metabolismo , Fagocitose
14.
Mem. Inst. Oswaldo Cruz ; 107(8): 1021-1029, Dec. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-660650

RESUMO

Because an enriched environment (EE) enhances T-cell activity and T-lymphocytes contribute to immunopathogenesis during heterologous dengue virus (DENV) infections, we hypothesised that an EE increases dengue severity. To compare single serotype (SS) and antibody-enhanced disease (AED) infections regimens, serial intraperitoneal were performed with DENV3 (genotype III) infected brain homogenate or anti-DENV2 hyperimmune serum followed 24 h later by DENV3 (genotype III) infected brain homogenate. Compared AED for which significant differences were detected between the EE and impoverished environmental (IE) groups (Kaplan-Meyer log-rank test, p = 0.0025), no significant differences were detected between the SS experimental groups (Kaplan-Meyer log-rank test, p = 0.089). Survival curves from EE and IE animals infected with the AED regimen were extended after corticoid injection and this effect was greater in the EE than in the IE group (Kaplan-Meyer log-rank test, p = 0.0162). Under the AED regimen the EE group showed more intense clinical signs than the IE group. Dyspnoea, tremor, hunched posture, ruffled fur, immobility, pre-terminal paralysis, shock and death were associated with dominant T-lymphocytic hyperplasia and presence of viral antigens in the liver and lungs. We propose that the increased expansion of these memory T-cells and serotype cross-reactive antibodies facilitates the infection of these cells by DENV and that these events correlate with disease severity in an EE.


Assuntos
Animais , Feminino , Camundongos , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Vírus da Dengue/imunologia , Dengue/imunologia , Linfócitos B/imunologia , Dengue/virologia , Ecologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia
15.
Mem Inst Oswaldo Cruz ; 107(8): 1021-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23295753

RESUMO

Because an enriched environment (EE) enhances T-cell activity and T-lymphocytes contribute to immunopathogenesis during heterologous dengue virus (DENV) infections, we hypothesised that an EE increases dengue severity. To compare single serotype (SS) and antibody-enhanced disease (AED) infections regimens, serial intraperitoneal were performed with DENV3 (genotype III) infected brain homogenate or anti-DENV2 hyperimmune serum followed 24 h later by DENV3 (genotype III) infected brain homogenate. Compared AED for which significant differences were detected between the EE and impoverished environmental (IE) groups (Kaplan-Meyer log-rank test, p = 0.0025), no significant differences were detected between the SS experimental groups (Kaplan-Meyer log-rank test, p = 0.089). Survival curves from EE and IE animals infected with the AED regimen were extended after corticoid injection and this effect was greater in the EE than in the IE group (Kaplan-Meyer log-rank test, p = 0.0162). Under the AED regimen the EE group showed more intense clinical signs than the IE group. Dyspnoea, tremor, hunched posture, ruffled fur, immobility, pre-terminal paralysis, shock and death were associated with dominant T-lymphocytic hyperplasia and presence of viral antigens in the liver and lungs. We propose that the increased expansion of these memory T-cells and serotype cross-reactive antibodies facilitates the infection of these cells by DENV and that these events correlate with disease severity in an EE.


Assuntos
Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Vírus da Dengue/imunologia , Dengue/imunologia , Animais , Linfócitos B/imunologia , Dengue/virologia , Ecologia , Feminino , Ativação Linfocitária/imunologia , Camundongos , Linfócitos T/imunologia
16.
Prion ; 5(3): 215-27, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21862877

RESUMO

Behavioral and neuropathological changes have been widely investigated in murine prion disease but stereological based unbiased estimates of key neuropathological features have not been carried out. After injections of ME7 infected (ME7) or normal brain homogenates (NBH) into dorsal CA1 of albino Swiss mice and C57BL6, we assessed behavioral changes on hippocampal-dependent tasks. We also estimated by optical fractionator at 15 and 18 weeks post-injections (w.p.i.) the total number of neurons, reactive astrocytes, activated microglia and perineuronal nets (PN) in the polymorphic layer of dentate gyrus (PolDG), CA1 and septum in albino Swiss mice. On average, early behavioral changes in albino Swiss mice start four weeks later than in C57BL6. Cluster and discriminant analysis of behavioral data in albino Swiss mice revealed that four of nine subjects start to change their behavior at 12 w.p.i. and reach terminal stage at 22 w.p.i and the remaining subjects start at 22 w.p.i. and reach terminal stage at 26 w.p.i. Biotinylated dextran-amine BDA-tracer experiments in mossy fiber pathway confirmed axonal degeneration, and stereological data showed that early astrocytosis, microgliosis and reduction in the perineuronal nets are independent of a change in the number of neuronal cell bodies. Statistical analysis revealed that the septal region had greater levels of neuroinflammation and extracellular matrix damage than CA1. This stereological and multivariate analysis at early stages of disease in an outbred model of prion disease provided new insights connecting behavioral changes and neuroinflammation and seems to be important to understand the mechanisms of prion disease progression.


Assuntos
Comportamento Animal , Neurônios/patologia , Doenças Priônicas/patologia , Doenças Priônicas/psicologia , Animais , Modelos Animais de Doenças , Feminino , Gliose/metabolismo , Gliose/patologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia
17.
PLoS One ; 6(1): e15597, 2011 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-21264301

RESUMO

An enriched environment has previously been described as enhancing natural killer cell activity of recognizing and killing virally infected cells. However, the effects of environmental enrichment on behavioral changes in relation to virus clearance and the neuropathology of encephalitis have not been studied in detail. We tested the hypothesis that environmental enrichment leads to less CNS neuroinvasion and/or more rapid viral clearance in association with T cells without neuronal damage. Stereology-based estimates of activated microglia perineuronal nets and neurons in CA3 were correlated with behavioral changes in the Piry rhabdovirus model of encephalitis in the albino Swiss mouse. Two-month-old female mice maintained in impoverished (IE) or enriched environments (EE) for 3 months were behaviorally tested. After the tests, an equal volume of Piry virus (IEPy, EEPy)-infected or normal brain homogenates were nasally instilled. Eight days post-instillation (dpi), when behavioral changes became apparent, brains were fixed and processed to detect viral antigens, activated microglia, perineuronal nets, and T lymphocytes by immuno- or histochemical reactions. At 20 or 40 dpi, the remaining animals were behaviorally tested and processed for the same markers. In IEPy mice, burrowing activity decreased and recovered earlier (8-10 dpi) than open field (20-40 dpi) but remained unaltered in the EEPy group. EEPy mice presented higher T-cell infiltration, less CNS cell infection by the virus and/or faster virus clearance, less microgliosis, and less damage to the extracellular matrix than IEPy. In both EEPy and IEPy animals, CA3 neuronal number remained unaltered. The results suggest that an enriched environment promotes a more effective immune response to clear CNS virus and not at the cost of CNS damage.


Assuntos
Comportamento Animal , Sistema Nervoso Central/virologia , Encefalite Viral/imunologia , Microglia/metabolismo , Infecções por Rhabdoviridae/imunologia , Animais , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/patologia , Encefalite Viral/patologia , Encefalite Viral/virologia , Feminino , Camundongos , Neurônios , Rhabdoviridae , Infecções por Rhabdoviridae/patologia , Linfócitos T/imunologia , Linfócitos T/virologia , Resultado do Tratamento
18.
Cytokine ; 51(2): 202-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20621721

RESUMO

BACKGROUND: Chromoblastomycosis (CBM) is a dermal mycosis. The disease evolves to a chronic state, presenting a suppurative granulomatous dermatitis, combined with variable dermal fibrosis. Pathogenesis of the inflammation and tissue repair in CBM are poorly understood. AIM: To quantify Transforming Growth Factor-beta (TGF-beta) plasma levels of CBM patients during itraconazole (ITZ) treatment. METHODS: Blood plasma of 12 CBM patients was subjected to TGF-beta titration with ELISA at 0, 3, 6 and 12months of 200mg per day of ITZ therapy, and correlated with the clinical aspects. Plasma of 12 healthy individuals were used for control. RESULTS: CBM patients present high plasma levels of TGF-beta (7.016+/-1988pg/ml), decreasing after 03months (4.625+/-645pg/ml) of ITZ treatment, which correlates with a rapid clinical improvement. However, after 6 (6.566+/-777pg/ml) and 12months (6.908+/-776) of treatment, TGF-beta levels increase to almost the same levels observed before treatment, which is related to a slow clinical improvement, fungal persistence on the lesion, and fibrotic scars. CONCLUSION: TGF-beta plasma levels are high in CBM patients. Fungal destruction by ITZ correlates with TGF-beta downregulation, but tissue remodeling and fungal persistence probably raises its levels again, interfering with cellular immune responses.


Assuntos
Cromoblastomicose/sangue , Cromoblastomicose/tratamento farmacológico , Itraconazol/uso terapêutico , Fator de Crescimento Transformador beta/sangue , Adulto , Cromoblastomicose/patologia , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade
19.
J Clin Microbiol ; 46(11): 3839-41, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18799695

RESUMO

Fonsecaea pedrosoi is the main agent of chromoblastomycosis, a skin disease presenting verrucous lesions, in which round, thick-walled sclerotic cells are found. In vitro induction of sclerotic cells is time-consuming (20 to 45 days) and temperature dependent. We present two new natural media that reduce the sclerotic-cell induction time to only 2 days.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Meios de Cultura/química , Micologia/métodos , Ascomicetos/citologia
20.
J. vasc. bras ; 7(3): 262-266, set. 2008. ilus
Artigo em Português | LILACS | ID: lil-500245

RESUMO

Os aneurismas venosos são entidades raras, porém com potencialidade de causar complicações tromboembólicas. Na maioria das vezes, são encontrados incidentalmente, como achados de exame físico ou de imagem. Os aneurismas sintomáticos de veia poplítea são obrigatoriamente tratados por reparo cirúrgico, devido ao alto risco de recorrência de embolia pulmonar. A técnica mais utilizada é a aneurismectomia tangencial com venorrafia lateral. Na impossibilidade de se empregar essa técnica, faz-se a ressecção com reconstrução venosa. Os autores relatam o caso de uma paciente com aneurisma de veia poplítea, cujo diâmetro era de 47 mm, submetido a aneurismectomia tangencial e venorrafia lateral, com sucesso.


Venous aneurysms are considered to be a rare disease; however they can be a potential cause for the development of thromboembolism. They are mostly detected by physical examination or imaging exams. Symptomatic aneurysms of the popliteal vein must be surgically treated, due to high risk of recurrent pulmonary embolism. The most widely used procedure is tangential aneurysmectomy and lateral venorrhaphy. If not possible, the aneurysm should be removed and a venous reconstruction should be performed. The authors report a case of a patient with a popliteal vein aneurysm measuring 47 mm in diameter. Tangential aneurysmectomy and lateral venorrhaphy were successfully used for treatment.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Aneurisma/cirurgia , Veia Poplítea/cirurgia , Fatores de Risco
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