21 research outputs found
Diagnóstico etiológico de aborto infeccioso bovino por PCR
Infectious abortion is a significant cause of reproductive failure and economic losses in cattle. The goal of this study was to detect nucleic acids of several infectious agents known to cause abortion including Arcanobacterium pyogenes, Bovine Herpesvirus 1, Brucella abortus, Campylobacter fetus subsp. venerealis, Chlamydophila abortus, Leptospira sp., Listeria monocytogenes, Salmonella sp., Mycoplasma bovis, Mycoplasma bovigenitalium, Neospora caninum, and Tritrichomonas foetus. Tissue homogenates from 42 fetuses and paraffin-embedded tissues from 28 fetuses and 14 placentas/endometrium were included in this study. Brucella abortus was detected in 14.2% (12/84) of the samples. Salmonella sp. DNA was amplified from 2 fetuses, and there was one positive for Neospora caninum, and another for Listeria monocytogenes. This PCR-based approach resulted in identification of the etiology in 19% of samples, or 20% if considered fetal tissues only.Aborto infeccioso é uma causa significativa de falhas reprodutivas e perdas econômicas na bovinocultura. O objetivo deste estudo foi detectar ácidos nucleicos de vários agentes infecciosos reconhecidos como causadores de aborto, incluindo-se Arcanobacterium pyogenes, Herpesvirus bovino tipo 1, Brucella abortus, Campylobacter fetus subsp. venerealis, Chlamydophila abortus, Leptospira sp., Listeria monocytogenes, Salmonella sp., Mycoplasma bovis, Mycoplasma bovigenitalium, Neospora caninum e Tritrichomonas foetus. Homogenados de tecidos de 42 fetos e tecidos incluídos em parafina de 28 fetos e 14 placentas/endométrio foram incluídos neste estudo. Brucella abortus foi detectada em 14,2% (12/84) das amostras. DNA de Salmonella sp. foi amplificado de dois fetos e houve um feto positivo para Neospora caninum e outro para Listeria monocytogenes. Essa metodologia baseada em PCR resultou na identificação da etiologia em 19% das amostras ou 20% se considerados somente os tecidos fetais
Systemic infection by Spencermartinsiella sp. in a Nile crocodile (Crocodylus niloticus)
A male adult crocodile (Crocodylus niloticus) was diagnosed with systemic yeast infection. Histologically, there were extensive areas of necrosis in the lung, which were associated with a diffuse severe lympho-plasmo-histiocytic inflammatory infiltrate, with numerous multinucleated giant cells, and myriads of intralesional pseudo-hyphae and yeast like organisms within distended foveolae. Necrotic foci were also observed in the mucosa of the digestive tract, trachea, tunica intima of arteries, liver, and heart, with a marked inflammatory lympho-histiocytic infiltrate, with large numbers of epithelioid macrophages and giant cells, and intralesional and intravascular pseudo-hyphae and yeast-like organisms. Oval yeast structures with 4 to 6 μm in diameter and 5 to 8 μm thick paralleled-wall pseudo-hyphae were observed in PAS or GMS stained sections. PCR with DNA template extracted from paraffin embedded tissues amplified the D1/D2 domains of the large subunit rRNA gene, which was sequenced and found to be identical to sequences of a new species, isolated from rotting wood in Brazil, of the genus Spencermartinsiella, which its closest relative is Spencermartinsiella cellulosicola. Um crocodilo macho adulto (Crocodylus niloticus) foi diagnosticado com infecção fúngica sustêmica. Histologicamente, havia extensas áreas de necrose no pulmão, que estavam associadas com infiltrado inflamatório linfo-plasmo-histiocitário, com numerosas células gigantes multinucleadas e miríade de pseudo-hifas e organismos leveduriformes intralesionais, dentro de favéolas distendidas. Focos necróticos também foram observados na mucosa do trato digestório, traquéia, túnica íntima de artérias, fígado e coração, com acentuado infiltrado inflamatório linfo-histiocitário, com grande número de macrófagos epitelioides e células gigantes e hifas e organismos leveduriformes intralesionais e intravasculares. Cortes corados por PAS e GMS evidenciaram estruturas leveduriformes ovais com 4 a 6 μm de diâmetro e pseudo-hifas de paredes espessas e paralelas com 5 a 8 μm. PCR realizado com DNA extraído de material parafinizado amplificou os domínios D1/D2 da subunidade maior do gene rRNA, cuja sequencia foi idêntica a sequências de uma nova espécie, isolada no Brasil de madeira em decomposição, do gênero Spencermartinsiella, cuja espécie mais próxima é Spencermartinsiella cellulosicola
Pathogenicity of psychrotolerant strains of Antarctic Pseudogmynoascus fungi reveals potential opportunistic profiles
Recent studies have demonstrated the presence of fungal taxa in the extreme ecosystems of Antarctica that are known to opportunistically infect humans and animals. Among these are members of the genus Pseudogymnoascus, including some that are genetically similar to P. destructans, known to be pathogenic to bats. We evaluated the in vitro and in vivo pathogenic potential of 11 Pseudogymnoascus spp. strains recovered from Antarctica. All strains were able to grow at temperatures up to 28 °C and displayed in vitro pathogenicity through hemolytic activity, growth at different pH levels, production of hydrolytic enzymes, spore diameters, tolerance to oxidative stress, hypoxia, and halotolerance. Among them, Pseudogymnoascus sp. UFMG 8532 exhibited strong in vitro pathogenicity and in preliminary in vivo assay killed 100 % of Tenebrio molitor larvae within one day. The pathogenicity of the same strain was also tested using immunosuppressed BALB/c mouse models. Survival of BALB/c mice was affected, with oscillations between weight gain and loss, and impacts on sensory function, reflexes and autonomic function. Histopathological data from the organs of infected mice showed evidence of inflammatory processes, with numerous neutrophils, a small number of macrophages, fluid accumulation inside the lungs and intense hyperemia. Our results indicate that Antarctic Pseudogymnoascus spp. strains obtained from various substrates/habitats in maritime Antarctica may possess intrinsic virulence factors and pathogenic potential for immunosuppressed animals and humans in the region. Given that the Antarctic environment is an important reservoir for Pseudogymnoascus species, which display growth performance across a range of temperatures, it is possible that increasing temperatures in the maritime Antarctic could activate dormant genes or biochemical pathways, select virulent species and/or strains, and facilitate their spread within and beyond the region. The ability of Pseudogymnoascus species to grow slowly even at 28°C, coupled with their potential in vitro and in vivo virulence factors, suggests that these fungi might be undergoing an opportunistic transition due to the effects of climate change on the Antarctic Peninsula
Anti-Sarcocystis neurona immunostaining associated with equine protozoal myeloencephalitis in Brazil Imunomarcação de Sarcocystis neurona associada com um caso de mieloencefalite protozoária eqüina no Brasil
A retrospective study (1942 to 2005) of histopathological lesions included samples of central nervous system (SNC) from 203 animals in the Equidae family. A total of 42.4% of these samples had significant pathological changes, which were classified as inflammatory (62.8%), degenerative (25.6%), circulatory (10.5%), and neoplasic (1.1%) lesions. Immunohistochemistry anti-Sarcocystis neurona antigens was performed in all the cases with inflammatory changes (54), of which one of the case of encephalitis resulted positive to immunostaining. Although evidence of EPM (Equine Protozoal Myeloencephalitis) has been previously reported in Brazil, to the best of our knowledge, this is the first report in which characteristic EPM lesion was associated with anti-S. neurona immunostaining in Brazil.<br>Em um estudo retrospectivo (de 1942 a 2005), amostras do sistema nervoso central de 203 eqüídeos foram avaliadas para a presença de alterações histológicas. Dessas amostras, 42,4% apresentaram alguma lesão histopatológica significativa, das quais foram classificadas como alterações inflamatórias (62,8%), degenerativas (25,6%), circulatórias (10,5%) e neoplásicas (1,1%). Fragmentos de SNC dos 54 animais com alterações inflamatórias foram avaliados para detecção de antígenos de Sarocystis neurona pela técnica de imunoistoquímica, que foi positiva em um caso de encefalite em eqüino. Embora haja registros de MPE no Brasil, este é o primeiro caso confirmado imunoistoquimicamente
Cholelithiasis with atrophy of the right lateral hepatic lobe in a horse Colelitíase com atrofia do lobo lateral direito em um cavalo
A 22 year-old horse developed cholelithiasis with marked atrophy of the right lateral hepatic lobe. The horse had a history of intermittent colic since three years of age, and one of the first episodes of colic was associated with icterus. The size of the right lateral hepatic lobe was extremely reduced. There was a large choledocholith in the common hepatic duct, and several hepatoliths and choleliths in the intra- and extra-hepatic billiary ducts. Microscopically, there was severe atrophy of the right lobe with diffuse proliferation of connective tissue and billiary ducts. The left lateral lobe had peri-portal fibrosis with proliferation of billiary ducts, and billiary stasis. Chemical analysis of the calculi detected amorphous and triple phosphate, bilirubin, calcium, and iron.<br>Um cavalo de 22 anos de idade desenvolveu quadro de colelitíase severa com atrofia do lobo lateral direito. O animal tinha histórico de cólica recorrente, desde os três anos de idade, sendo que um dos primeiros episódios de cólica foi acompanhado de icterícia. O lobo hepático lateral direito estava extremamente diminuído de volume. Havia um grande coledocólito localizado no ducto hepático comum e inúmeros hepatólitos e colélitos nos ductos biliares intra e extra-hepáticos. Microscopicamente, foi observada atrofia acentuada do lobo direito, com proliferação difusa de tecido conjuntivo fibroso e de ductos biliares. O lobo lateral esquerdo apresentava fibrose periportal difusa associada à proliferação acentuada de ductos biliares e estase biliar. Análise química das concreções detectou fosfato triplo e amorfo, bilirrubina, cálcio e ferro