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1.
J Comp Pathol ; 156(1): 25-28, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27899174

RESUMEN

Brain tumours in cattle are uncommon and the spontaneous development of primary brain tumours of different histological types is rare in both man and animals. In man, multiple concurrent primary tumours of different types are occasionally described. We report the rare simultaneous occurrence of two different primary brain tumours, gliosarcoma and choroid plexus carcinoma, diagnosed by microscopical and immunofluorescence evaluation in an 8-year-old cow with a 2-month history of neurological disease. Gliosarcoma is a rare variant of glioblastoma multiforme, characterized by the presence of malignant glial cells and mesenchymal tissue. This tumour has not been reported previously in animals.


Asunto(s)
Neoplasias Encefálicas/veterinaria , Carcinoma/veterinaria , Enfermedades de los Bovinos/patología , Neoplasias del Plexo Coroideo/veterinaria , Gliosarcoma/veterinaria , Neoplasias Primarias Múltiples/veterinaria , Animales , Bovinos , Femenino
2.
J Comp Pathol ; 155(4): 339-345, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27817831

RESUMEN

Streptococcus agalactiae, the aetiological agent of streptococcosis in fish, is an important pathogen of cultured and wild fish worldwide. To gain a better understanding of the pathogenesis of streptococcosis in Nile tilapia (Oreochromis niloticus), and to identify the experimental route of infection that most closely mimics natural disease, fingerlings were challenged with S. agalactiae utilizing different delivery methods. Fingerlings were challenged via intracoelomic injection (ICinj), intramuscular injection (IMinj), orally or by immersion with serial dilutions of S. agalactiae. The dose lethal to 50% of test fish 15 days post challenge was 120 colony forming units (CFU)/fish after ICinj, and 105 CFU/fish after IMinj. Acute mortalities were present in both groups, but were higher in the fish challenged by ICinj. Very low mortalities were observed in the fish challenged via oral or immersion routes. Post-mortem evaluation of survivors revealed classical lesions associated with fish streptococcosis, including granulomatous or lymphohistiocytic epicarditis, splenitis, meningitis, myocarditis, choroiditis and exophthalmia. The information obtained improves our understanding of the pathogenesis of streptococcosis in fish, and provides useful information regarding controlled experimental infections in tilapia challenged with S. agalactiae. Results from this study suggest that IMinj challenge methods are not only suitable to induce streptococcosis in tilapia, but they may be the preferred method to study the pathogenesis of the naturally-occurring disease in this species.


Asunto(s)
Cíclidos/microbiología , Modelos Animales de Enfermedad , Enfermedades de los Peces/patología , Infecciones Estreptocócicas/veterinaria , Animales , Enfermedades de los Peces/microbiología
3.
J Comp Pathol ; 126(4): 303-7, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12056778

RESUMEN

A 23-month-old, male, Labrador retriever dog with a history of slowly progressive right-sided atrophy of the masticatory muscles was submitted for necropsy. A highly invasive neoplasm which destroyed adjacent soft tissues including the right trigeminal nerve was found in the right side of the cranial cavity. Metastases to the liver were also present. Microscopical features of the neoplasm were compatible with those of rhabdomyosarcoma, embryonal type. This diagnosis was confirmed by immunohistochemical demonstration of desmin and muscle actin within tumour cells. In human patients, rhabdomyosarcoma is the most common soft tissue sarcoma of childhood and adolescence. Parameningeal rhabdomyosarcomas are well-known topographic variants that are often non-amenable to complete surgical resection and therefore carry a more guarded prognosis. Juvenile parameningeal rhabdomyosarcoma resulting in denervation atrophy of the muscles of mastication has not been reported previously in dogs. Rhabdomyosarcoma should be included in the differential diagnosis of neoplastic conditions in the head and neck region of juvenile dogs presented with cranial nerve palsies or other neurological deficits suggestive of meningeal or central nervous system invasion.


Asunto(s)
Enfermedades de los Perros/patología , Neoplasias de Cabeza y Cuello/veterinaria , Neoplasias Meníngeas/veterinaria , Rabdomiosarcoma Embrionario/veterinaria , Actinas/análisis , Animales , Desmina/análisis , Perros , Resultado Fatal , Neoplasias de Cabeza y Cuello/patología , Inmunohistoquímica/veterinaria , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/veterinaria , Masculino , Neoplasias Meníngeas/química , Neoplasias Meníngeas/patología , Rabdomiosarcoma Embrionario/química , Rabdomiosarcoma Embrionario/secundario
4.
Can Vet J ; 41(5): 401-3, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10816835

RESUMEN

Adenocarcinoma of sweat glands of the footpads was diagnosed in 2 cats. Clinical signs included lameness and swelling of multiple digits. Pulmonary metastasis was detected in one case. Diagnosis was based on histopathological and immunohistochemical findings. Eccrine adenocarcinoma should be included in the differential diagnosis of footpads lesions in aged cats.


Asunto(s)
Adenocarcinoma/veterinaria , Enfermedades de los Gatos/patología , Glándulas Ecrinas/patología , Neoplasias de las Glándulas Sudoríparas/veterinaria , Adenocarcinoma/patología , Animales , Gatos , Diagnóstico Diferencial , Pie/patología , Inmunohistoquímica , Cojera Animal/etiología , Masculino , Neoplasias de las Glándulas Sudoríparas/patología
7.
Lab Invest ; 69(6): 724-35, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8264234

RESUMEN

BACKGROUND: The temporal localization of cellular targets for viral replication and the morphopathogenesis of neurodegeneration in the central nervous system (CNS) and peripheral nervous system induced by ts1, a neuropathogenic and lymphocytopathic mutant of Moloney murine leukemia virus-TB, were studied in the highly susceptible FVB/N mouse strain in order to better understand the mechanisms of this neurodegenerative disease. EXPERIMENTAL DESIGN: Newborn FVB/N mice were inoculated intraperitoneally with 0.1 ml of viral suspension containing 10(6) to 10(7) infectious units/ml. The mice were observed daily for clinical signs of disease and killed at specific time points. Their nervous system tissues were collected and processed for light and electron microscopy and for immunohistochemical viral-antigen detection. RESULTS: ts1-Infected FVB/N mice developed a rapidly progressive wasting disease that culminated in hindleg paralysis or paraplegia 30 to 35 days postinoculation (pi). CONCLUSIONS: Clear evidence of CNS lesions involving the cerebellar ventricular system, the grey and white matter of the brain stem and the spinal cord were seen as early as 5 to 10 days pi. These lesions, which began as mild perivascular and paraventricular neuropil spongiform changes and cytoplasmic vacuolation of neuronal and glial cell processes, progressed in severity with time and culminated in almost complete destruction of the white and gray matter in the brain stem and the cervical and lumbar spinal cord. Viruses were detected as early as 5 to 10 days pi in the fourth ventricle choroid plexus and ventricular lumen and budding from endothelial cells within the brain stem and cerebellum. Endothelial, ependymal, microglial, astroglial, and oligodendroglial cells were positive for gp70env. Astroglial and microglial cell proliferation with microglial syncytia formation was detected only within the areas showing spongiform degeneration. Viral replication was consistently high in the capillary endothelial cells of those areas showing spongiform degeneration, whereas in the glial cells, relatively few budding viruses were present. Neurodegeneration was accompanied by demyelinization within the CNS and peripheral nervous system and by hindleg muscle degeneration and necrosis. Multiple cellular targets for ts1 viral infection and replication were detected within the nervous system. The presence of budding virus and the immunodetection of viral antigen in the choroid plexus and ependymal cells of the fourth ventricle and the central canal of the spinal cord demonstrated that cerebrospinal fluid as well as blood can disseminate virus within the CNS. Pathologic and functional changes within the blood-brain barrier and glial system probably account for the neuronal necrosis and spongiform changes that result in paralysis induced by ts1 infection.


Asunto(s)
Sistema Nervioso Central/patología , Virus de la Leucemia Murina de Moloney/patogenicidad , Enfermedades del Sistema Nervioso/patología , Parálisis/microbiología , Sistema Nervioso Periférico/patología , Animales , Astrocitos/citología , Tronco Encefálico/patología , Sistema Nervioso Central/microbiología , Epéndimo/patología , Bulbo Raquídeo/patología , Ratones , Ratones Endogámicos , Microscopía Electrónica , Enfermedades del Sistema Nervioso/microbiología , Parálisis/patología , Sistema Nervioso Periférico/microbiología , Nervio Ciático/patología , Médula Espinal/microbiología , Médula Espinal/patología , Factores de Tiempo , Replicación Viral
8.
Lab Invest ; 66(4): 427-36, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1583883

RESUMEN

Inoculation of newborn FVB/N mice with ts1, a mutant of Moloney murine leukemia virus TB, induced severe thymic atrophy, spongiform polioencephalomyelopathy, and fatal posterior paralysis of the affected mice 35-40 days after inoculation. During the early course of infection viral replication was found in the spleen and, more importantly, within the thymus. Of these organs, the thymus was affected most severely by ts1-infection. Thymic weights of infected mice decreased markedly during disease progression, culminating in severe atrophy at the time of paralysis. During the first 10 days after inoculation, the virus replicated within the endothelial lining of splenic and thymic capillaries and was released albuminally into the basement membrane before spreading outwardly into perithelial, epithelial, and reticuloendothelial cells. Within these cells there was productive viral replication and subsequent dissemination of the virus to the thymic T cell population. Early infection (up to 10 days after inoculation) of the thymus induced an increase in thymocytic mitosis, followed by a progressive increase in thymocytic death between 15 and 35 days after inoculation. Thymuses from paralyzed mice killed 30-39 days after inoculation, demonstrated pronounced involution, characterized by loss of lobular architecture, effacement of the cortex and medulla, severe depletion of thymocytes, and partial or complete loss of Hassall's corpuscles. Immunohistochemistry for viral antigens showed positive labeling of splenic megakaryocytes, reticuloendothelial cells, and thymocytes in mitosis, and reticulo-epithelial-endothelial cells of the thymus. The thymic phase of viral replication appeared to be crucial for development of neurological lesions and posterior paralysis.


Asunto(s)
Endotelio Vascular/patología , Leucemia Experimental/patología , Virus de la Leucemia Murina de Moloney/fisiología , Timo/patología , Animales , Animales Recién Nacidos , Atrofia , Endotelio Vascular/microbiología , Leucemia Experimental/genética , Hígado/microbiología , Hígado/patología , Ganglios Linfáticos/microbiología , Ganglios Linfáticos/patología , Ratones , Virus de la Leucemia Murina de Moloney/genética , Mutación , Parálisis , Bazo/microbiología , Bazo/patología , Timo/microbiología , Factores de Tiempo
9.
Acta Neuropathol ; 79(5): 551-7, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2158203

RESUMEN

A light and electron microscopic study was undertaken to determine pathological changes in cutaneous spinal nerves of rabbits following intradermal inoculation with alphaherpesvirus saimiri (alpha HVS) isolate KM 322. Infected rabbits were killed at 3, 10, 17, 45 days and 2 years after infection. No abnormalities were seen at 3 days postinoculation. In the nerves of the rabbits killed at 10, 17 and 45 days after infection, axonal (Wallerian-type) degeneration was the main pathological feature. Regeneration, manifested by axonal sprouting, was observed in the nerves of the rabbits killed at 45 days post-inoculation. Neural fibrosis and paucity of unmyelinated axons was the final outcome. The severity of the neural damage not only varied according to the progression of the disease but between nerves taken from the same rabbit. This was probably associated with variation in the numbers of virus particles that had reached the dorsal root ganglion of the dermatome served by a particular nerve. Since alpha HVS (isolate KM 322) provides a model system for the study of virus latency in dorsal root ganglia, and consequently for the study of varicellazoster infection in man, these findings give further insight into the pathology of herpetic neuropathy.


Asunto(s)
Infecciones por Herpesviridae/patología , Piel/inervación , Nervios Espinales/patología , Infecciones Tumorales por Virus/patología , Animales , Herpesvirus Saimiriino 2 , Microscopía Electrónica , Conejos , Nervios Espinales/microbiología
10.
Acta Neuropathol ; 79(5): 558-65, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2158204

RESUMEN

To provide a better insight into the ultrastructural pathology of herpetic neuropathy, quantitative studies were made on cutaneous spinal nerves of normal rabbits and rabbits intradermally infected with alphaherpesvirus saimiri (alpha HVS) isolate KM 322. Marked reductions in the numbers and densities of myelinated and unmyelinated axons were found in the nerves of the rabbits killed 17 and 45 days after the infection. Abnormalities in the size distribution of unmyelinated axons were seen at 45 days post-inoculation where axonal sprouting caused a noticeable shift in the fiber population. Two years after virus inoculation reduction in unmyelinated axons and abnormalities in the fiber size distributions characterized by smaller diameters of both myelinated and unmyelinated axons were detected. In these nerves conspicuous fibrosis caused a significant increase in the endoneurial area. At this stage of the infection regenerative changes involving myelinated fibers were found. Since attempts to detect spontaneous reactivation of alpha HVS infection in rabbits have been unsuccessful, the finding of regeneration 2 years after exposure seems in agreement with the view that regenerated myelinated fibers never attain their original size. In the present study although both types of fibers were damaged, morphometric data suggest that unmyelinated axons were more severely affected. Whether this seemingly selective involvement was due to spreading of the virus between axons sharing the same Schwann cell subunit remains to be proved.


Asunto(s)
Infecciones por Herpesviridae/patología , Piel/inervación , Nervios Espinales/patología , Infecciones Tumorales por Virus/patología , Animales , Axones/patología , Recuento de Células , Herpesvirus Saimiriino 2 , Conejos , Nervios Espinales/microbiología
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