ß-micrustoxin (Mlx-9), a PLA2 from Micrurus lemniscatus snake venom: biochemical characterization and anti-proliferative effect mediated by p53

Background: Endogenous phospholipases A2 (PLA2 ) play a fundamental role in inflammation, neurodegenerative diseases, apoptosis and cellular senescence. Neurotoxins with PLA2 activity are found in snake venoms from the Elapidae and Viperidae families. The mechanism of action of these neurotoxins have been studied using hippocampal and cerebellar neuronal cultures showing [Ca2+]i increase, mitochondrial depolarization and cell death. Astrocytes are rarely used as a model, despite being modulators at the synapses and responsible for homeostasis and defense in the central nervous system. Preserving the cell division ability, they can be utilized to study the cell proliferation process. In the present work cultured astrocytes and glioblastoma cells were employed to characterize the action of ß-micrustoxin (previously named Mlx-9), a PLA2 isolated from Micrurus lemniscatus snake venom. The ß-micrustoxin structure was determined and the cell proliferation, cell cycle phases and the regulatory proteins p53, p21 and p27 were investigated. Methods: ß-micrustoxin was characterized biochemically by a proteomic approach. Astrocytes were obtained by dissociation of pineal glands from Wistar rats; glioblastoma tumor cells were purchased from ATCC and Sigma and cultured in DMEM médium. Cell viability was evaluated by MTT assay; cell proliferation and cell cycle phases were analyzed by flow cytometry; p53, p21 and p27 proteins were studied by western blotting and immunocytochemistry. Results: Proteomic analysis revealed fragments on ß-micrustoxin that aligned with a PLA2 from Micrurus lemniscatus lemniscatus previously identified as transcript ID DN112835_C3_g9_i1/m.9019. ß-micrustoxin impaired the viability of astrocytes and glioblastoma tumor cells. There was a reduction in cell proliferation, an increase in G2/M phase and activation of p53, p21 and p27 proteins in astrocytes. Conclusion: These findings indicate that ß-micrustoxin from Micrurus lemniscatus venom could inhibit cell proliferation through p53, p21 and p27 activation thus imposing cell cycle arrest at the checkpoint G2/M.(AU)

Susceptibility of goats to poisoning by Tephrosia cinérea / Suscetibilidade de caprinos à intoxicação por Tephrosia cinerea

Spontaneous and experimental poisoning by Tephrosia cinerea in the northeastern semiarid region of Brazil has only been described in sheep. Pathologically, such poisoning leads to ascites and centrilobular liver fibrosis. However, these effects require an experimental study in goats. This study aimed to determine the goats' susceptibility to the ingestion of T. cinerea and the minimum toxic dose, describing the main clinical and anatomopathological findings. Poisoning was reproduced experimentally in one sheep that received 10g/kg of the ground plant and in two goats, the first receiving a dose of 5g/kg and the second receiving 10g/kg of the ground plant. The sheep presented abdominal distension 34 days after beginning the ingestion of the plant, developing sternal decubitus, breathing difficulty, opisthotonos, mandibular trismus, salivation, dysphagia, vocalization, and pedaling movements on the 50th day of the experiment. Fluid accumulation was observed in the abdominal cavity and liver via necropsy, with an irregular, slightly whitish capsular surface. Histologically, the main lesions observed in the liver were moderate fibrosis, marked sinusoidal distension, accompanied by marked hemorrhage, sometimes forming bridges between the centrilobular regions, associated with a dissociation of hepatocyte cords. There were discrete Alzheimer's type II astrocytes in the gray matter in the region of the occipital cortex in the nervous system. Goat 2 showed apathy, drowsiness, and weight loss; on the 62th day, lateral decubitus evolved to sternal decubitus, with a rotation of the neck towards the flank. At necropsy, marked edema was observed on the face and dewlap, and a slight accumulation of liquid; slightly yellowish material was observed in the abdominal cavity. There were discrete blackened areas on the capsular surface in the liver. Histologically, the liver showed mild centrilobular fibrosis associated with mild dissociation of hepatocyte cords and mild vacuolar degeneration of the hepatocyte cytoplasm. Goat 1 showed no clinical signs; at necropsy, discrete multifocal areas were observed in the liver on the capsular surface. Histologically, diffuse intracytoplasmic vacuolar degeneration of hepatocytes was detected. The clinical picture and anatomopathological findings differ between the species, proving the lower susceptibility of goats to Tephrosia cinerea ingestion (compared to sheep), with differences in the pathogenesis and epidemiological aspects of poisoning.

A intoxicação espontânea e experimental por Tephrosia cinerea no semiárido nordestino só foi descrita em ovinos. Patologicamente, tal intoxicação leva a ascite e fibrose hepática centrolobular. No entanto, esses efeitos requerem um estudo experimental em caprinos. Este estudo teve como objetivo determinar a suscetibilidade de caprinos à ingestão de T. cinerea e a dose tóxica mínima, descrevendo os principais achados clínicos e anatomopatológicos. A intoxicação foi reproduzida experimentalmente em um ovino que recebeu 10g/kg da planta moída e em dois caprinos, o primeiro recebendo a dose de 5g/kg e o segundo recebendo 10g/kg da planta moída. O ovino apresentou distensão abdominal 34 dias após o início da ingestão da planta, desenvolvendo decúbito esternal, dificuldade respiratória, opistótono, trismo mandibular, salivação, disfagia, vocalização e movimentos de pedalada no 50º dia do experimento. Foi observado acúmulo de líquido na cavidade abdominal e fígado via necropsia, com superfície capsular irregular e levemente esbranquiçada. Histologicamente, as principais lesões observadas no fígado foram fibrose moderada, distensão sinusoidal acentuada, acompanhada de hemorragia acentuada, por vezes formando pontes entre as regiões centrolobulares, associada à dissociação dos cordões de hepatócitos. Havia discretos astrócitos de Alzheimer tipo II na substância cinzenta na região do córtex occipital no sistema nervoso. A cabra 2 apresentou apatia, sonolência e perda de peso; no 62º dia, decúbito lateral evoluiu para decúbito esternal, com rotação do pescoço em direção ao flanco. Na necropsia, observou-se edema acentuado na face e barbela, e leve acúmulo de líquido; foi observado material levemente amarelado na cavidade abdominal. Havia áreas enegrecidas discretas na superfície capsular no fígado. Histologicamente, o fígado apresentava leve fibrose centrolobular associada à discreta dissociação dos cordões de hepatócitos e leve degeneração vacuolar do citoplasma dos hepatócitos. A cabra 1 não apresentou sinais clínicos; na necropsia, discretas áreas multifocais foram observadas no fígado na superfície capsular. Histologicamente, foi detectada degeneração vacuolar intracitoplasmática difusa dos hepatócitos. O quadro clínico e os achados anatomopatológicos diferem entre as espécies, comprovando a menor suscetibilidade dos caprinos à ingestão de Tephrosia cinerea (em relação aos ovinos), com diferenças na patogênese e aspectos epidemiológicos da intoxicação.

Crotalaria spectabilis poisoning in a horse

Plant poisoning is an important cause of death in horses and cattle in Brazil. Crotalaria spp. has stood out in this scenario due to its toxic potential caused by monocrotaline, a pyrrolizidine alkaloid found throughout the plant, mainly in seeds. Here is reported a case of Crotalaria spectabilis poisoning a horse. A horse consumed oats contaminated with Crotalaria spectabilis seed and presented clinical signs of toxicosis characterized by jaundice, progressive weight loss, hemoglobinuria, subcutaneous edema in the pectoral region and neurological symptoms typical of hepatic encephalopathy. In the serum evaluation, there was an increase in the activity of the enzymes alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT) and aspartate transaminase (AST), urea, creatinine and creatine phosphokinase (CPK). At necropsy, the main macroscopic findings were opaque and congested liver with capsular irregularity and accentuated the lobular pattern, trachea with foamy and pinkish fluid and congested and edematous pulmonary lobes. The main histopathological findings were hepatic fibrosis, periportal ductal hyperplasia, centrilobular necrosis, megalocytosis and binucleated hepatocytes. The brain parenchyma showed perivascular edema and Alzheimer type II astrocytes. Crotalaria spp. is among the main plants that cause acute or chronic mortality after exposure to the toxic compound in horses and farm animals.(AU)

Crotalaria spectabilis poisoning in a horse

Plant poisoning is an important cause of death in horses and cattle in Brazil. Crotalaria spp. has stood out in this scenario due to its toxic potential caused by monocrotaline, a pyrrolizidine alkaloid found throughout the plant, mainly in seeds. Here is reported a case of Crotalaria spectabilis poisoning a horse. A horse consumed oats contaminated with Crotalaria spectabilis seed and presented clinical signs of toxicosis characterized by jaundice, progressive weight loss, hemoglobinuria, subcutaneous edema in the pectoral region and neurological symptoms typical of hepatic encephalopathy. In the serum evaluation, there was an increase in the activity of the enzymes alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT) and aspartate transaminase (AST), urea, creatinine and creatine phosphokinase (CPK). At necropsy, the main macroscopic findings were opaque and congested liver with capsular irregularity and accentuated the lobular pattern, trachea with foamy and pinkish fluid and congested and edematous pulmonary lobes. The main histopathological findings were hepatic fibrosis, periportal ductal hyperplasia, centrilobular necrosis, megalocytosis and binucleated hepatocytes. The brain parenchyma showed perivascular edema and Alzheimer type II astrocytes. Crotalaria spp. is among the main plants that cause acute or chronic mortality after exposure to the toxic compound in horses and farm animals.

Neuroprotection and immunomodulation by dimethyl fumarate and a heterologous fibrin biopolymer after ventral root avulsion and reimplantation

Ventral root avulsion (VRA) is an experimental approach in which there is an abrupt separation of the motor roots from the surface of the spinal cord. As a result, most of the axotomized motoneurons degenerate by the second week after injury, and the significant loss of synapses and increased glial reaction triggers a chronic inflammatory state. Pharmacological treatment associated with root reimplantation is thought to overcome the degenerative effects of VRA. Therefore, treatment with dimethyl fumarate (DMF), a drug with neuroprotective and immunomodulatory effects, in combination with a heterologous fibrin sealant/biopolymer (FS), a biological glue, may improve the regenerative response. Methods: Adult female Lewis rats were subjected to VRA of L4-L6 roots followed by reimplantation and daily treatment with DMF for four weeks. Survival times were evaluated 1, 4 or 12 weeks after surgery. Neuronal survival assessed by Nissl staining, glial reactivity (anti-GFAP for astrocytes and anti-Iba-1 for microglia) and synapse preservation (anti-VGLUT1 for glutamatergic inputs and anti-GAD65 for GABAergic inputs) evaluated by immunofluorescence, gene expression (pro- and anti-inflammatory molecules) and motor function recovery were measured. Results: Treatment with DMF at a dose of 15 mg/kg was found to be neuroprotective and immunomodulatory because it preserved motoneurons and synapses and decreased astrogliosis and microglial reactions, as well as downregulated the expression of pro-inflammatory gene transcripts. Conclusion: The pharmacological benefit was further enhanced when associated with root reimplantation with FS, in which animals recovered at least 50% of motor function, showing the efficacy of employing multiple regenerative approaches following spinal cord root injury.(AU)

The effect of rosmarinic acid on deformities occurring in brain tissue by craniectomy method: histopathological evaluation of IBA-1 and GFAP expressions

Purpose To investigate the role of Rosmarinic acid (RA) in the prevention of traumatic brain injury and the immunohistochemical analysis of IBA-1 and GFAP expressions. Methods Healthy male rats were randomly divided into 3 groups consisting of 10 rats. Groups were as follows; control group, traumatic brain injury (TBI) group, and TBI+RA group. After traumatic brain injury, blood samples were taken from the animals and analyzed with various biochemical markers. And then IBA-1 and GFAP expressions were evaluated immunohistochemically. Results Significant results were obtained in all biochemical parameters between groups. Immunohistochemical sections showed IBA-1 not only in microglia and macrophage activity but also in degenerative neurons in blood vessel endothelial cells. However, GFAP reaction and post-traumatic rosmarinic acid administration showed positive expression in astrocytes with regular structure around the blood vessel. Conclusion Rosmarinic acid in blood vessel endothelial cells showed that preserving the integrity of astrocytic structure in the blood brain barrier may be an important antioxidant.(AU)

Neuroprotection and immunomodulation by dimethyl fumarate and a heterologous fibrin biopolymer after ventral root avulsion and reimplantation

Background: Ventral root avulsion (VRA) is an experimental approach in which there is an abrupt separation of the motor roots from the surface of the spinal cord. As a result, most of the axotomized motoneurons degenerate by the second week after injury, and the significant loss of synapses and increased glial reaction triggers a chronic inflammatory state. Pharmacological treatment associated with root reimplantation is thought to overcome the degenerative effects of VRA. Therefore, treatment with dimethyl fumarate (DMF), a drug with neuroprotective and immunomodulatory effects, in combination with a heterologous fibrin sealant/biopolymer (FS), a biological glue, may improve the regenerative response. Methods: Adult female Lewis rats were subjected to VRA of L4-L6 roots followed by reimplantation and daily treatment with DMF for four weeks. Survival times were evaluated 1, 4 or 12 weeks after surgery. Neuronal survival assessed by Nissl staining, glial reactivity (anti-GFAP for astrocytes and anti-Iba-1 for microglia) and synapse preservation (anti-VGLUT1 for glutamatergic inputs and anti-GAD65 for GABAergic inputs) evaluated by immunofluorescence, gene expression (pro- and anti-inflammatory molecules) and motor function recovery were measured. Results: Treatment with DMF at a dose of 15 mg/kg was found to be neuroprotective and immunomodulatory because it preserved motoneurons and synapses and decreased astrogliosis and microglial reactions, as well as downregulated the expression of pro-inflammatory gene transcripts. Conclusion: The pharmacological benefit was further enhanced when associated with root reimplantation with FS, in which animals recovered at least 50% of motor function, showing the efficacy of employing multiple regenerative approaches following spinal cord root injury.(AU)

Canine distemper virus, atypical Toxoplasma gondii, and Neospora caninum co-infection, in a dog with neurological signs from Argentina

The occurrence of combined infections by Toxoplasma gondii, Neospora caninum and Canine distemper virus (CDV) in domestic dogs and wildlife animals has not been frequently reported, and the histopathological findings were not exhaustively described. The objective of this study was to report a co-infection of CDV, T. gondii and N. caninum in a dog with neurological signs, as well as the molecular characterization of the protozoa involved. A young street dog was rescued with neurological clinical signs and died spontaneously. A complete necropsy was performed. Tissues were collected and fixed for histopathological evaluation. Additionally, sections of the central nervous system (CNS) and heart were assayed by immunohistochemistry (IHQ) for T. gondii and N. caninum. Sample of brain tissue was analyzed by PCR and nPCR-RFLP for T. gondii genotyping. Spleen was used for detection of CDV by RT-PCR. Gross lesions were not observed, with the exception of the lung. Microscopically, a severe necrosuppurative meningoencephalitis with vasculitis, tachyzoites and bradyzoites of T. gondii and N. caninum were found. Demyelination was also evident, associated with eosinophilic intranuclear inclusion bodies within astrocytes. CDV was PCR positive while both parasites were presented PCR and IHQ positive results. Molecular characterization of T. gondii was reported as atypical #14 (likely). To our knowledge, this is the first report of genetical identification of T. gondii obtained from the brain of a naturally infected dog in Argentina. The results emphasize the importance of different techniques as diagnostic tools to enhance the detection of causative agents in cases of fatal encephalitis.

Poisoning by Senecio brasiliensis in horses in northern Rio Grande do Sul

Background: In various regions of Brazil, horses and cattle are considered the most susceptible animals to plant poisoning. The plants of the genus Senecio are the most important in Rio Grande do Sul because they have the active principleknown as the pyrrolizidine alkaloid. Its diagnosis is made through epidemiology, clinical signs and histopathologicalanalysis, either of the tissues obtained by biopsy or necropsy. The objective of this study was to report and characterizethe epidemiological, clinical and anatomopathological findings of three cases of natural poisoning by Senecio brasiliensisin horses assisted at the Hospital Veterinário (HV) of the Universidade de Passo Fundo (UPF).Cases: Three traction horses, two males and one female, were admitted at the HV-UPF for clinical care. The animals werepresenting anorexia, weight loss, dysmetria, proprioceptive deficit and signs suggestive of colic. The epidemiological studyrevealed that the sites where these animals were located were infested by Senecio brasiliensis. The support therapy usedfor equine colic in all three cases was unsuccessful. One of the animals died and the other two were euthanized, all threeof them being reffered for necropsy. The post-mortem findings were mainly found in the liver, which showed accentuationof the lobular pattern and the appearance of nutmeg. During necropsy, fragments of organs from thoracic and abdominalcavities and central nervous system were collected and fixed in 10% buffered formalin. Subsequently, the samples wereprocessed chemically, submitted to cuts of five micrometers of thickness and stained with hematoxylin and eosin for microscopic analysis. Microscopically, the liver of all three horses presented megalocytosis, fibrosis and bile ducts hyperplasia.In the central nervous system, spongiosis and the presence of Alzheimer type II astrocytes were observed. Thus, throughthe association of information, the diagnosis of...

Poisoning by Senecio brasiliensis in horses in northern Rio Grande do Sul

Background: In various regions of Brazil, horses and cattle are considered the most susceptible animals to plant poisoning. The plants of the genus Senecio are the most important in Rio Grande do Sul because they have the active principleknown as the pyrrolizidine alkaloid. Its diagnosis is made through epidemiology, clinical signs and histopathologicalanalysis, either of the tissues obtained by biopsy or necropsy. The objective of this study was to report and characterizethe epidemiological, clinical and anatomopathological findings of three cases of natural poisoning by Senecio brasiliensisin horses assisted at the Hospital Veterinário (HV) of the Universidade de Passo Fundo (UPF).Cases: Three traction horses, two males and one female, were admitted at the HV-UPF for clinical care. The animals werepresenting anorexia, weight loss, dysmetria, proprioceptive deficit and signs suggestive of colic. The epidemiological studyrevealed that the sites where these animals were located were infested by Senecio brasiliensis. The support therapy usedfor equine colic in all three cases was unsuccessful. One of the animals died and the other two were euthanized, all threeof them being reffered for necropsy. The post-mortem findings were mainly found in the liver, which showed accentuationof the lobular pattern and the appearance of nutmeg. During necropsy, fragments of organs from thoracic and abdominalcavities and central nervous system were collected and fixed in 10% buffered formalin. Subsequently, the samples wereprocessed chemically, submitted to cuts of five micrometers of thickness and stained with hematoxylin and eosin for microscopic analysis. Microscopically, the liver of all three horses presented megalocytosis, fibrosis and bile ducts hyperplasia.In the central nervous system, spongiosis and the presence of Alzheimer type II astrocytes were observed. Thus, throughthe association of information, the diagnosis of...(AU)

Canine distemper virus, atypical Toxoplasma gondii, and Neospora caninum co-infection, in a dog with neurological signs from Argentina

The occurrence of combined infections by Toxoplasma gondii, Neospora caninum and Canine distemper virus (CDV) in domestic dogs and wildlife animals has not been frequently reported, and the histopathological findings were not exhaustively described. The objective of this study was to report a co-infection of CDV, T. gondii and N. caninum in a dog with neurological signs, as well as the molecular characterization of the protozoa involved. A young street dog was rescued with neurological clinical signs and died spontaneously. A complete necropsy was performed. Tissues were collected and fixed for histopathological evaluation. Additionally, sections of the central nervous system (CNS) and heart were assayed by immunohistochemistry (IHQ) for T. gondii and N. caninum. Sample of brain tissue was analyzed by PCR and nPCR-RFLP for T. gondii genotyping. Spleen was used for detection of CDV by RT-PCR. Gross lesions were not observed, with the exception of the lung. Microscopically, a severe necrosuppurative meningoencephalitis with vasculitis, tachyzoites and bradyzoites of T. gondii and N. caninum were found. Demyelination was also evident, associated with eosinophilic intranuclear inclusion bodies within astrocytes. CDV was PCR positive while both parasites were presented PCR and IHQ positive results. Molecular characterization of T. gondii was reported as atypical #14 (likely). To our knowledge, this is the first report of genetical identification of T. gondii obtained from the brain of a naturally infected dog in Argentina. The results emphasize the importance of different techniques as diagnostic tools to enhance the detection of causative agents in cases of fatal encephalitis.(AU)

Leukoencephalomalacia in horses associated with immature corn consumption / Surto de leucoencefalomalacia em equinos associado ao consumo de milho verde

Horse leukoencephalomalacia (ELEM) is a disease caused by the ingestion of mycotoxins (fumonisins) produced by fungi of the genus Fusarium that infect corn and/or its byproducts. This disease has been described by ingestion of mature corn with humidity above 15% at temperatures below 20°C. The aim of this paper was to report an outbreak of leukoencephalomalacia in horses fed with immature corn. Two horses out of three showed neurological signs approximately seven days after eating immature corn in its reproductive phase (R2, milky grains). Corn was harvested and administered directly to the animals, with no storage. Deaths occurred approximately 24 hours after the onset of clinical signs. Grossly, there were multifocal dark red to brown areas in the white matter of the telencephalon and hyppocampus and thalamus. Histologically, there was edema and hemorrhage in several areas of the telencephalon white matter, which corresponded to dark red to brown areas observed in the macroscopy. There was also foci of malacia with presence of reactive astrocytes with abundant eosinophilic cytoplasm and inflammatory cells. Diffuse capillary wall degeneration and endothelial cell swelling were also observed. Two ppm of fumonisin were detected by immunoaffinity column method (VICAM) in the immature corn sample. The water activity in this cereal, when the grain is still milky, is 0.98 and can predispose it to growth of mycotoxin-producing fungi. In the present case, fumonisin was found in milky grains in the beginning of the reproductive phase (R2), which suggested that even immature corn may be infected by Fusarium spp. and should not be administered to horses.(AU)

A leucoencefalomalácia dos equinos (ELEM) é uma doença causada pela ingestão de micotoxinas (fumonisinas) produzidas por fungos do gênero Fusarium que infectam o milho e/ou seus subprodutos. A doença tem sido descrita pela ingestão de milho maduro com umidade acima de 15% em temperatura ambiente abaixo de 20°C. O objetivo deste trabalho foi relatar um surto de leucoencefalomacia em equinos alimentados com milho verde. Dois equinos de três animais apresentaram sinais clínicos neurológicos aproximadamente sete dias após iniciarem a ingestão de milho verde na fase reprodutiva (R2, grãos leitosos) com palha e talos, colhido no máximo 24 horas antes de ser administrado. A morte ocorreu aproximadamente 24 horas após o início dos sinais clínicos. Macroscopicamente havia no sistema nervoso central áreas multifocais acinzentadas e amareladas na substância branca do telencéfalo, no hipocampo e no tálamo. Histologicamente observou-se edema e hemorragia em diversas áreas da substância branca do telencéfalo, que correspondiam às áreas acinzentadas observadas na macroscopia. Havia, também, próximo as áreas hemorrágicas, focos de malacia com presença de astrócitos reativos com abundante citoplasma eosinophilico e algumas células inflamatórias. Degeneração das paredes dos capilares e tumefação das células endoteliais também foram observadas. Na análise da amostra de milho pelo método de colunas de imunoafinidade (VICAM) foram detectados 2ppm de fumonisina. A atividade de água neste cereal, quando o grão ainda está leitoso, é de 0,98, o que predispõe ao crescimento de fungos produtores de micotoxinas. No presente caso fumonisina foi encontrada nos grãos leitosos no início da fase reprodutiva (R2), o que sugere que mesmo o milho ainda imaturo pode estar infectado por Fusarium spp. e não deve, também, ser administrado aos equinos.(AU)

Encefalopatia hepática secundária à intoxicação por Tephrosia cinerea em ovinos

ABSTRACT: In the semiarid region of northeastern Brazil, Tephrosia cinerea causes periacinar hepatic fibrosis in sheep with severe ascites and, occasionally, nervous signs. Sixteen sheep from six outbreaks of T. cinerea poisoning were studied. All sheep had histologic lesion of periacinar fibrosis and six showed, in the brain, vacuolization (spongy degeneration) of the white matter and junction between grey and white matter and presence of Alzheimer type II astrocytes in the grey matter. The disease was produced experimentally in two sheep, that presented porto-sistemic shunts and similar histologic lesions as those observed in the spontaneous cases. Immunohistochemistry revealed weak labelling with anti-GFAP antibodies suggesting a degenerative alteration of astrocytes with accumulation of dense bodies and reduction of the GFAP. There was strong labelling with anti-S100 antibodies suggesting cellular reactivity with proliferation of mitochondria and endoplasmatic reticulum. Such alterations are characteristic of the effects caused by ammonia on the astrocytes. It is concluded that in poisoning by T. cinerea nervous signs due to hepatic encephalopathy occur in some sheep.

RESUMO: A intoxicação por Tephrosia cinerea causa fibrose hepática periacinar em ovinos na região semiárida do Nordeste, com quadro clínico de ascite acentuada, e, ocasionalmente, com sinais neurológicos. Neste trabalho foram estudadas 16 ovinos em 6 surtos de intoxicação por T. cinerea. Todos os ovinos apresentaram lesões histológicas de fibrose periacinar e seis apresentaram, no encéfalo, vacuolização da substância branca e da junção entre a substância branca e a cinzenta com presença de astrócitos de Alzheimer tipo II na substância cinzenta. A doença foi reproduzida experimentalmente em dois ovinos que apresentaram ascite, desvios vasculares (shunts) porto-sistêmicos e sinais nervosos com lesões histológicas semelhantes a dos casos espontâneos. Na técnica de imuno-histoquímica houve marcação fraca ou ausente do citoplasma astrocitário para o anticorpo anti-GFAP em seis ovinos evidenciando uma alteração degenerativa, em que os astrócitos acumulam corpos densos e reduzem o volume de GFAP. Houve marcação positiva para o anticorpo anti-S100 em oito ovinos, incluindo os dois ovinos experimentais o que sugere reatividade celular, com proliferação mitocondrial e de retículo endoplasmático liso. Estas alterações são caraterísticas dos efeitos da amônia nos astrócitos. Conclui-se que na intoxicação por T. cinerea em alguns ovinos ocorrem sinais nervosos em consequência da encefalopatia hepática.

Caracterização etiológica, epidemiológica e clínico-patológica da meningoencefalite por herpesvírus bovino em bovinos no Estado de Goiás

ABSTRACT: Twenty six cases of bovine herpetic meningoencephalitis diagnosed from 2010-2016 in Goiás state, Brazil, were studied. Affected cattle were mainly 60-day to 18-month-old. There was no association of the disease with sex and seasonality. The disease was found in all five mesoregions with a higher prevalence in southern and central state of Goiás. Clinical signs more frequently observed included blindness, incoordination, circling, excessive salivation, and ataxia. Main gross findings in the brain were congestion with swelling and flattening of gyri, softening and yellow discoloration of cerebral cortex and hemorrhagic foci. In five cases no gross changes were observed in the brain and in four cases there is no information. The main histopathological changes were in the cortex of telencephalic lobes, especially the frontal and parietal; however less prominent and less frequently found lesions occurred in the thalamus, basal nuclei, midbrain, pons, medulla oblongata, cerebellum, and hippocampus. All cases presented lymphoplasmocytic meningoencephalitis and intranuclear basophilic inclusion bodies in astrocytes, less commonly in neurons. Other frequent lesions included segmental laminar neuronal necrosis (red neurons), spongiosis, swollen vascular endothelial nuclei, gliosis (focal and diffuse), hypertrophy of astrocytes, infiltration of gitter cells, congestion, and hemorrhage. Lesions less frequently observed were Alzheimer type II astrocytes, residual lesion and neuronophagia. The most frequently affected cortical layers by neuronal necrosis and edema were external and internal granular, molecular, and pyramidal cell layers. Gyri and sulci were equally affected. Of the 26 cases, in 2 (7.69%) the DNA of BoHV-5 was amplified with samples fixed in 10% formalin and paraffin-embedded. DNA of BoHV-1 was identified in another case (3.84%) where, positive to BoHV-1, fresh samples were used.

RESUMO: Foram estudados 26 casos de meningoencefalite por herpesvírus bovino (BoHV) diagnosticados entre 2010-2016, no Estado de Goiás (GO). A doença acometeu principalmente bovinos jovens, entre 60 dias a 18 meses de idade. Não houve associação entre os casos e o sexo dos bovinos e a sazonalidade. A doença foi observada em todas as cinco Mesorregiões do Estado, com uma frequência maior nas Mesorregiões Sul e Centro. Os sinais clínicos mais frequentemente observados incluíram cegueira, incoordenação, sialorreia e ataxia. As principais alterações macroscópicas observadas incluíram congestão com tumefação e achatamento das circunvoluções, amolecimento e amarelamento do córtex telencefálico e focos de hemorragia. Em cinco encéfalos, não foram observadas alterações macroscópicas e em quatro as alterações não foram informadas. As principais alterações histológicas ocorreram no córtex telencefálico, principalmente o córtex frontal e parietal, mas em alguns casos, lesões de menor intensidade foram também observadas no tálamo, núcleos basais, mesencéfalo, ponte, bulbo, cerebelo e hipocampo. Todos os casos apresentaram meningoencefalite linfoplasmocítica e corpúsculos de inclusão intranucleares basofílicos em astrócitos e, eventualmente, em neurônios. Outras lesões frequentes incluíram necrose neuronal laminar segmentar (neurônio vermelho), espongiose, tumefação do núcleo das células endoteliais, gliose focal ou difusa, hipertrofia de astrócitos, infiltração por células gitter, congestão e hemorragia. Lesões menos comuns incluíram astrócitos Alzheimer tipo II, lesão residual e neuronofagia. A necrose neuronal e o edema (espongiose) foram mais acentuados nas camadas granular externa, molecular, de células piramidais e granular interna dos telencéfalos. Tanto os giros quanto os sulcos foram afetados igualmente. Dos 26 casos, o DNA de BoHV-5 foi amplificado em dois (7,69%) casos, enquanto que o de BoHV-1 foi identificado em um caso (3,84%). Nos casos positivos para BoHV-5 foram usadas amostras fixadas em formol a 10% e incluídas em parafina e amostras congeladas foram utilizadas no caso positivo para BoHV-1.

Encefalopatia hepática secundária à intoxicação por Tephrosia cinerea em ovinos / Hepatic encephalopathy secondary to poisoning by Tephrosia cinerea in sheep

A intoxicação por Tephrosia cinerea causa fibrose hepática periacinar em ovinos na região semiárida do Nordeste, com quadro clínico de ascite acentuada, e, ocasionalmente, com sinais neurológicos. Neste trabalho foram estudadas 16 ovinos em 6 surtos de intoxicação por T. cinerea. Todos os ovinos apresentaram lesões histológicas de fibrose periacinar e seis apresentaram, no encéfalo, vacuolização da substância branca e da junção entre a substância branca e a cinzenta com presença de astrócitos de Alzheimer tipo II na substância cinzenta. A doença foi reproduzida experimentalmente em dois ovinos que apresentaram ascite, desvios vasculares (shunts) porto-sistêmicos e sinais nervosos com lesões histológicas semelhantes a dos casos espontâneos. Na técnica de imuno-histoquímica houve marcação fraca ou ausente do citoplasma astrocitário para o anticorpo anti-GFAP em seis ovinos evidenciando uma alteração degenerativa, em que os astrócitos acumulam corpos densos e reduzem o volume de GFAP. Houve marcação positiva para o anticorpo anti-S100 em oito ovinos, incluindo os dois ovinos experimentais o que sugere reatividade celular, com proliferação mitocondrial e de retículo endoplasmático liso. Estas alterações são caraterísticas dos efeitos da amônia nos astrócitos. Conclui-se que na intoxicação por T. cinerea em alguns ovinos ocorrem sinais nervosos em consequência da encefalopatia hepática.(AU)

In the semiarid region of northeastern Brazil, Tephrosia cinerea causes periacinar hepatic fibrosis in sheep with severe ascites and, occasionally, nervous signs. Sixteen sheep from six outbreaks of T. cinerea poisoning were studied. All sheep had histologic lesion of periacinar fibrosis and six showed, in the brain, vacuolization (spongy degeneration) of the white matter and junction between grey and white matter and presence of Alzheimer type II astrocytes in the grey matter. The disease was produced experimentally in two sheep, that presented porto-sistemic shunts and similar histologic lesions as those observed in the spontaneous cases. Immunohistochemistry revealed weak labelling with anti-GFAP antibodies suggesting a degenerative alteration of astrocytes with accumulation of dense bodies and reduction of the GFAP. There was strong labelling with anti-S100 antibodies suggesting cellular reactivity with proliferation of mitochondria and endoplasmatic reticulum. Such alterations are characteristic of the effects caused by ammonia on the astrocytes. It is concluded that in poisoning by T. cinerea nervous signs due to hepatic encephalopathy occur in some sheep.(AU)

Encefalopatia hepática secundária à intoxicação por Tephrosia cinerea em ovinos / Hepatic encephalopathy secondary to poisoning by Tephrosia cinerea in sheep

A intoxicação por Tephrosia cinerea causa fibrose hepática periacinar em ovinos na região semiárida do Nordeste, com quadro clínico de ascite acentuada, e, ocasionalmente, com sinais neurológicos. Neste trabalho foram estudadas 16 ovinos em 6 surtos de intoxicação por T. cinerea. Todos os ovinos apresentaram lesões histológicas de fibrose periacinar e seis apresentaram, no encéfalo, vacuolização da substância branca e da junção entre a substância branca e a cinzenta com presença de astrócitos de Alzheimer tipo II na substância cinzenta. A doença foi reproduzida experimentalmente em dois ovinos que apresentaram ascite, desvios vasculares (shunts) porto-sistêmicos e sinais nervosos com lesões histológicas semelhantes a dos casos espontâneos. Na técnica de imuno-histoquímica houve marcação fraca ou ausente do citoplasma astrocitário para o anticorpo anti-GFAP em seis ovinos evidenciando uma alteração degenerativa, em que os astrócitos acumulam corpos densos e reduzem o volume de GFAP. Houve marcação positiva para o anticorpo anti-S100 em oito ovinos, incluindo os dois ovinos experimentais o que sugere reatividade celular, com proliferação mitocondrial e de retículo endoplasmático liso. Estas alterações são caraterísticas dos efeitos da amônia nos astrócitos. Conclui-se que na intoxicação por T. cinerea em alguns ovinos ocorrem sinais nervosos em consequência da encefalopatia hepática.(AU)

In the semiarid region of northeastern Brazil, Tephrosia cinerea causes periacinar hepatic fibrosis in sheep with severe ascites and, occasionally, nervous signs. Sixteen sheep from six outbreaks of T. cinerea poisoning were studied. All sheep had histologic lesion of periacinar fibrosis and six showed, in the brain, vacuolization (spongy degeneration) of the white matter and junction between grey and white matter and presence of Alzheimer type II astrocytes in the grey matter. The disease was produced experimentally in two sheep, that presented porto-sistemic shunts and similar histologic lesions as those observed in the spontaneous cases. Immunohistochemistry revealed weak labelling with anti-GFAP antibodies suggesting a degenerative alteration of astrocytes with accumulation of dense bodies and reduction of the GFAP. There was strong labelling with anti-S100 antibodies suggesting cellular reactivity with proliferation of mitochondria and endoplasmatic reticulum. Such alterations are characteristic of the effects caused by ammonia on the astrocytes. It is concluded that in poisoning by T. cinerea nervous signs due to hepatic encephalopathy occur in some sheep.(AU)

The protection effect and mechanism of hyperbaric oxygen therapy in rat brain with traumatic injury

Purpose: To investigate the effect of hyperbaric oxygen therapy (HBOT) on traumatic brain injury (TBI) outcome. Methods: The modified Marmarou's weight drop device was used to generate non-lethal moderate TBI rat model, and further developed in vitro astrocytes culturing system. Then, we analyzed the expression changes of interested genes and protein by quantitative PCR and western blot. Results: Multiple HBO treatments significantly reduced the expression of apoptosis promoting genes, such as c-fos, c-jun, Bax and weakened the activation of Caspase-3 in model rats. On the contrary, HBOT alleviated the decrease of anti-apoptosis gene Bcl-2 and promoted the expression of neurotrophic factors (NTFs), such as NGF, BDNF, GDNF and NT-3 in vivo. As a consequent, the neuropathogenesis was remarkably relied with HBOT. Astrocytes from TBI brain or those cultured with 21% O2 density expressed higher NTFs than that of corresponding controls, from sham brain and cultured with 7% O2, respectively. The NTFs expression was the highest in astrocytes form TBI brain and cultured with 21% O2, suggesting a synergistic effect existed between TBI and the following HBO treatment in astrocytes. Conclusion: Our findings provided evidence for the clinical usage of HBO treating brain damages.(AU)

Healing of brain lesions in sheep recovered from amprolium-induced polioencephalomalacia

ABSTRACT: To evaluate the outcome of acute lesions in the brains of sheep that completely clinically recover from acute polioencephalomalacia (PEM), ten sheep were used in this experiment. Eight of those sheep received varying doses of amprolium to induce PEM. Four sheep were treated intramuscularly with 40mg/kg/body weight with thiamine to allow recovery and four sheep were left untreated. Two control sheep did not receive either amprolium or thiamine and were kept along with the other eight sheep for the duration of the experiment. Except for the two drugs, the diet and water source were the same for the ten sheep. Two sheep receiving high daily doses of amprolium and one sheep receiving a lower dose had acute deaths and developed acute brain lesions consisting of neuronal laminar cortical necrosis (red neurons), edema, reactive astrocytes, swollen endothelial cells and gitter cells infiltration. Four sheep that recovered from lower doses of amprolium-induced PEM after being treated with thiamine and another one that recovered spontaneously were euthanatized six months after clinical recovery and had gross changes consisting of segmental absence of cortical tissue. Histologically these segmental cortex-deprived areas corresponded to quasi-empty spaces where only vessels and gitter cells existed. No changes were seen in the brains of the two control sheep.

RESUMO: Para avaliar a evolução das lesões agudas no cérebro de ovinos que se recuperam clinicamente de polioencefalomalacia aguda (PEM), dez ovinos foram usados neste experimento. Oito desses ovinos receberam doses variáveis de amprólio para induzir PEM. Quatro ovinos foram tratados intramuscularmente com 40mg/kg/peso corporal de tiamina para permitir a recuperação, e outros quatro ficaram sem tratamento. Dois ovinos controles não receberam amprólio nem tiamina e foram mantidos com os outros oito ovinos durante a duração do experimento. Exceto pelas duas drogas, a dieta e a fonte de água eram as mesmas para os dez ovinos. Dois ovinos que receberam doses diárias altas de amprólio, e um que recebeu doses menores, tiveram mortes agudas e desenvolveram lesões cerebrais constituídas por necrose neuronal laminar cortical (neurônios vermelhos), edema, tumefação de células endoteliais, astrócitos reativos, tumefação de células endoteliais e infiltração por células gitter. Quatro ovinos que se recuperam da PEM induzida por amprólio, após tratamento com tiamina, e outro que se recuperou espontaneamente, permaneceram clinicamente normais e foram submetidos a eutanásia seis meses após a recuperação clínica. Na necropsia, apresentavam alterações macroscópicas caracterizadas por ausência segmentar de tecido corticocerebral. Histologicamente, essas áreas privadas de tecido cortical consistiam de espaços praticamente vazios onde apenas vasos e células gitter eram vistos. Não foram encontradas alterações no encéfalo das duas ovelhas controle.

Caracterização etiológica, epidemiológica e clínico-patológica da meningoencefalite por herpesvírus bovino em bovinos no Estado de Goiás / Etiological, epidemiological, clinical and pathological characterization of meningoencephalitis in cattle by bovine herpesvirus in the State of Goiás, Brazil

Foram estudados 26 casos de meningoencefalite por herpesvírus bovino (BoHV) diagnosticados entre 2010-2016, no Estado de Goiás (GO). A doença acometeu principalmente bovinos jovens, entre 60 dias a 18 meses de idade. Não houve associação entre os casos e o sexo dos bovinos e a sazonalidade. A doença foi observada em todas as cinco Mesorregiões do Estado, com uma frequência maior nas Mesorregiões Sul e Centro. Os sinais clínicos mais frequentemente observados incluíram cegueira, incoordenação, sialorreia e ataxia. As principais alterações macroscópicas observadas incluíram congestão com tumefação e achatamento das circunvoluções, amolecimento e amarelamento do córtex telencefálico e focos de hemorragia. Em cinco encéfalos, não foram observadas alterações macroscópicas e em quatro as alterações não foram informadas. As principais alterações histológicas ocorreram no córtex telencefálico, principalmente o córtex frontal e parietal, mas em alguns casos, lesões de menor intensidade foram também observadas no tálamo, núcleos basais, mesencéfalo, ponte, bulbo, cerebelo e hipocampo. Todos os casos apresentaram meningoencefalite linfoplasmocítica e corpúsculos de inclusão intranucleares basofílicos em astrócitos e, eventualmente, em neurônios. Outras lesões frequentes incluíram necrose neuronal laminar segmentar (neurônio vermelho), espongiose, tumefação do núcleo das células endoteliais, gliose focal ou difusa, hipertrofia de astrócitos, infiltração por células gitter, congestão e hemorragia. Lesões menos comuns incluíram astrócitos Alzheimer tipo II, lesão residual e neuronofagia. A necrose neuronal e o edema (espongiose) foram mais acentuados nas camadas granular externa, molecular, de células piramidais e granular interna dos telencéfalos. Tanto os giros quanto os sulcos foram afetados igualmente. Dos 26 casos, o DNA de BoHV-5 foi amplificado em dois (7,69%) casos, enquanto que o de BoHV-1 foi identificado em um caso (3,84%)...(AU)

Twenty six cases of bovine herpetic meningoencephalitis diagnosed from 2010-2016 in Goiás state, Brazil, were studied. Affected cattle were mainly 60-day to 18-month-old. There was no association of the disease with sex and seasonality. The disease was found in all five mesoregions with a higher prevalence in southern and central state of Goiás. Clinical signs more frequently observed included blindness, incoordination, circling, excessive salivation, and ataxia. Main gross findings in the brain were congestion with swelling and flattening of gyri, softening and yellow discoloration of cerebral cortex and hemorrhagic foci. In five cases no gross changes were observed in the brain and in four cases there is no information. The main histopathological changes were in the cortex of telencephalic lobes, especially the frontal and parietal; however less prominent and less frequently found lesions occurred in the thalamus, basal nuclei, midbrain, pons, medulla oblongata, cerebellum, and hippocampus. All cases presented lymphoplasmocytic meningoencephalitis and intranuclear basophilic inclusion bodies in astrocytes, less commonly in neurons. Other frequent lesions included segmental laminar neuronal necrosis (red neurons), spongiosis, swollen vascular endothelial nuclei, gliosis (focal and diffuse), hypertrophy of astrocytes, infiltration of gitter cells, congestion, and hemorrhage. Lesions less frequently observed were Alzheimer type II astrocytes, residual lesion and neuronophagia. The most frequently affected cortical layers by neuronal necrosis and edema were external and internal granular, molecular, and pyramidal cell layers. Gyri and sulci were equally affected. Of the 26 cases, in 2 (7.69%) the DNA of BoHV-5 was amplified with samples fixed in 10% formalin and paraffin-embedded. DNA of BoHV-1 was identified in another case (3.84%) where, positive to BoHV-1, fresh samples were used.(AU)

Kernicterus in an adult dog

Background: Kernicterus or bilirubin encephalopathy is a condition rarely observed in animal characterized by a yellowish discoloration of the central nervous system. It is a potentially fatal condition due to bilirubin neurotoxic effects caused by the increase of non-conjugated bilirubin pigment, which passes blood brain barrier and has been attributed to an imbalance between albumin and bilirubin levels. Intracellular bilirubin is toxic for cells and can cause decrease in protein synthesis, specially albumin, depression of cell respiration and cellular death. This paper describes kernicterus in a 2-year-old Great Dane female dog.Case: Clinically, the animal showed apathy, lethargy, weight loss and jaundice, which progressed to vomiting and neurological signs characterized by loss of consciousness and eventually coma. Blood parameters were within normal range, except for high levels of alanine aminotransferase (523 U/L), suggesting a liver lesion. The animal was submitted to euthanasia due to the poor prognosis, and at post-mortem examination it showed dehydration and severe jaundice, especially oral, vaginal and ocular mucosas, subcutaneous tissue and blood vessels intima surface. The liver had an accentuated lobular pattern, and the stomach mucosa was reddened. Multiple petechiae were observed in the epicardium, as well as icterus in the blood vessels of the heart. Furthermore, the brain and cerebellum cortex, thalamic region and nuclei region of brainstem showed extensive icteric areas. Microscopically, the liver presented a mononuclear portal hepatitis, centrilobular necrosis and presence of yellowish pigments. The brain had neuronal necrosis, mild vacuolization of the white matter, perineuronal edema and Alzheimer type II astrocytes, while cerebellum showed Purkinje cells necrosis. Hepatic cooper measurement was within range values, and direct imunofluorescence for the detection of Leptospira sp. was negative.[...]