ABSTRACT
Dengue virus (DENV) infections may result in asymptomatic cases or evolve into a severe disease, which involves multiple organ failure. Renal involvement in dengue can be potentially related to an increased mortality. Aiming to better understand the role of DENV in renal injury observed in human fatal cases, post-mortem investigations were performed in four DENV-4 renal autopsies during dengue epidemics in Brazil. Tissues were submitted to histopathology, immunohistochemistry, viral quantification, and characterization of cytokines and inflammatory mediators. Probably due the high viral load, several lesions were observed in the renal tissue, such as diffuse mononuclear infiltration around the glomerulus in the cortical region and in the medullary vessels, hyalinosis arteriolar, lymphocytic infiltrate, increased capsular fibrosis, proximal convoluted tubule (PCT) damage, edema, PCT debris formation, and thickening of the basal vessel membrane. These changes were associated with DENV-4 infection, as confirmed by the presence of DENV-specific NS3 protein, indicative of viral replication. The exacerbated presence of mononuclear cells at several renal tissue sites culminated in the secretion of proinflammatory cytokines and chemokines. Moreover, it can be suggested that the renal tissue injury observed here may have been due to the combination of both high viral load and exacerbated host immune response.
ABSTRACT
Mycetoma is caused by the subcutaneous inoculation of filamentous fungi or aerobic filamentous bacteria that form grains in the tissue. The purpose of this study is to describe the epidemiologic, clinic, laboratory, and therapeutic characteristics of patients with mycetoma at the Oswaldo Cruz Foundation in Rio de Janeiro, Brazil, between 1991 and 2014. Twenty-one cases of mycetoma were included in the study. There was a predominance of male patients (1.3:1) and the average patient age was 46 years. The majority of the cases were from the Southeast region of Brazil and the feet were the most affected anatomical region (80.95%). Eumycetoma prevailed over actinomycetoma (61.9% and 38.1% respectively). Eumycetoma patients had positive cultures in 8 of 13 cases, with isolation of Scedosporium apiospermum species complex (n = 3), Madurella mycetomatis (n = 2) and Acremonium spp. (n = 1). Two cases presented sterile mycelium and five were negative. Six of 8 actinomycetoma cases had cultures that were identified as Nocardia spp. (n = 3), Nocardia brasiliensis (n = 2), and Nocardia asteroides (n = 1). Imaging tests were performed on all but one patients, and bone destruction was identified in 9 cases (42.68%). All eumycetoma cases were treated with itraconazole monotherapy or combined with fluconazole, terbinafine, or amphotericin B. Actinomycetoma cases were treated with sulfamethoxazole plus trimethoprim or combined with cycles of amikacin sulphate. Surgical procedures were performed in 9 (69.2%) eumycetoma and in 3 (37.5%) actinomycetoma cases, with one amputation case in each group. Clinical cure occurred in 11 cases (7 for eumycetoma and 4 for actinomycetoma), and recurrence was documented in 4 of 21 cases. No deaths were recorded during the study. Despite of the scarcity of mycetoma in our institution the cases presented reflect the wide clinical spectrum and difficulties to take care of this neglected disease.
Subject(s)
Fungi/isolation & purification , Mycetoma/epidemiology , Mycetoma/pathology , Nocardia/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Antifungal Agents/therapeutic use , Brazil/epidemiology , Child , Child, Preschool , Debridement , Female , Fungi/classification , Humans , Infant , Infant, Newborn , Male , Middle Aged , Mycetoma/microbiology , Mycetoma/therapy , Treatment Outcome , Young AdultABSTRACT
A avaliação do curso da infecção por Toxoplasma gondii em camundongos alimentados com micotoxinas, utilizando a histopatologia e imuno-histoquímica, demonstrou a ocorrência de lesões mais acentuadas nos animais infectados e expostos às toxinas. Diferentes quadros de inflamação e necrose encefálica e hepática mostraram que a associação entre parasitismo e a ingestão das micotoxinas causou agravamento nas lesões. A fumonisina B1(FB1, isolada ou associada a outras micotoxinas) foi responsável por alterações celulares como gigantismo nuclear, hipertrofia celular e células atípicas em tecido hepático. A FB1 foi também relacionada com quadros de desmielinização em tecido cerebral. A presença de cistos ou formas livres da cepa ME-49 de T. gondii foi constatada tanto em animais controle quanto nos alimentados com micotoxinas, mostrando que a cepa do parasita, nesta linhagem C57BL/6 de camundongos, apresenta formas características de fase aguda e crônica da infecção.
The course of toxoplasmosis in mice fed with mycotoxins was evaluated by histopatology and immunohistochemistry. The most severe lesions was seen in animals infected by T. gondii and fed on mycotoxins, when they were compered with control animals. Encephalitis, hepatitis, necrosis foci in the brain and liver showed that the association parasite infection and micotoxicosis aggravated the lesions. The fumonisin B1(isolated or in adiccion to others mycotoxins) was responsable for cellular alteration like nuclear enlargement, cellular hypertrophy, and atypical cells in hepatic tissue. This mycotoxin was also related to brain desmyelinization. The presence of cysts or free parasites was observed in control and intoxicated animals. This result showed that ME49 strain of T. gondii, in C57BL/6 mice, can display typical forms of acute and chronic infection.
Subject(s)
Guinea Pigs , Mice/classification , Immunohistochemistry/methods , Pathology , Diet , Parasitic Diseases , Inflammation/complications , Mycotoxins/adverse effects , Toxoplasma/pathogenicityABSTRACT
Necropsy findings in three cases of naturally occurring toxoplasmosis in squirrel monkeys (Saimiri sciureus) obtained as wild catches from the Amazon region were described. Histopathological evaluation of the liver, spleen, kidneys and mesenteric lymph nodes showed multiple foci of inflammation and necrosis. Typical, well-defined morphologic Toxoplasma gondii cysts and free forms of the parasite were found by immunoperoxidase staining within inflammatory infiltrates. The presence of T. gondii in the studied colony could severely influence the results of experiments performed in the animals.
Achados de necropsia em três casos de toxoplasmose ocorridos naturalmente em macacos-de-cheiro (Saimiri sciureus) obtidos de capturas na região Amazônica foram descritos. A avaliação histopatológica do fígado, baço, rins e linfonodos mesentéricos mostrou múltiplos focos de inflamação e necrose. Cistos morfológicos típicos e bem definidos de Toxoplasma gondii e formas livres foram detectados pelo método da imunoperoxidase com infiltrados inflamatórios. A presença de T. gondii na colônia de primatas estudada pode influenciar severamente os resultados de experimentos realizados nos animais.
ABSTRACT
Objetivo: O objetivo deste trabalho é analisar a regeneração morfológica de tecido esplênico auto-implantado em ratos Wistar, verificando a função fagocitária bacteriana de seus macrófagos. Métodos: Utilizou-se um modelo experimental com ratos jovens e adultos, de ambos os sexos, submetidos a esplenectomia total combinada com auto-implante de fatias de toda a massa esplênica no omento maior. Dezesseis semanas após, os animais foram inoculados por via intravenosa com suspensão de Escherichia coli AB1157 e, após 20 minutos, foram mortos por dose letal de halotano, sendo submetidos a laparotomia para retirada dos auto-implantes esplênicos. A análise estatística foi realizada com o teste t de Student, com ênfase na comparação da massa de auto-implante esplênico regenerada entre animais jovens e adultos de ambos os sexos. Resultados: Ocorreu regeneração do auto-implante esplênico em todos os animais. Machos jovens e fêmeas adultas apresentaram maior percentual de regeneração. Observou-se aspecto morfológico microscópico semelhante em todos os animais. O tecido esplênico regenerado mostrou as polpas vermelha e branca, com desarranjo arquitetural moderado, bem como folículos linfóides. Os vasos sangüíneos mostravam paredes preservadas, sem sinais de vasculite ou trombose. Foram encontrados macrófagos contendo grumos de bactérias, bem como macrófagos contendo pigmento de hemossiderina intracitoplasmáticos. Conclusão: O auto-implante esplênico, no omento maior, em ratos, adquire a arquitetura macro e microscópica de um baço normal, de dimensão menor e preserva a função fagocitária bacteriana.