Shapes of pathology

ABSTRACT: The shape is one of the key features of a lesion and a pathologist must be able to identify and interpret these forms in the context of any gross and microscopic changes. One of the principles of adult learning is to engage the learner with previously understood information. If, when presenting material that is new, a connection with something the student already has familiarity with, the learning process is accelerated. As the learners are already familiar with shapes they have encountered throughout their pre-pathology learning, these can be used to hasten the incorporation and understanding of lesions. This paper describes various shapes that are used in describing lesions in veterinary pathology.

RESUMO: A forma é uma das principais características de uma lesão. Um patologista deve ser capaz de identificar e interpretar essas formas no contexto de quaisquer alterações macroscópicas ou microscópicas. Um dos princípios da aprendizagem de adultos é envolver o aluno com informações previamente compreendidas. Se, ao apresentar um material novo, se estabelece uma conexão com algo que o aluno já conhece, o processo de aprendizagem torna-se mais rápido e eficiente. Como os alunos já estão familiarizados com as formas que encontraram ao longo de sua aprendizagem pré-patologia, elas podem ser usadas para acelerar a incorporação e a compreensão das lesões. Este artigo descreve várias formas que são usadas na descrição de lesões em patologia veterinária.

Shapes of pathology / As formas da patologia

The shape is one of the key features of a lesion and a pathologist must be able to identify and interpret these forms in the context of any gross and microscopic changes. One of the principles of adult learning is to engage the learner with previously understood information. If, when presenting material that is new, a connection with something the student already has familiarity with, the learning process is accelerated. As the learners are already familiar with shapes they have encountered throughout their pre-pathology learning, these can be used to hasten the incorporation and understanding of lesions. This paper describes various shapes that are used in describing lesions in veterinary pathology.(AU)

A forma é uma das principais características de uma lesão. Um patologista deve ser capaz de identificar e interpretar essas formas no contexto de quaisquer alterações macroscópicas ou microscópicas. Um dos princípios da aprendizagem de adultos é envolver o aluno com informações previamente compreendidas. Se, ao apresentar um material novo, se estabelece uma conexão com algo que o aluno já conhece, o processo de aprendizagem torna-se mais rápido e eficiente. Como os alunos já estão familiarizados com as formas que encontraram ao longo de sua aprendizagem pré-patologia, elas podem ser usadas para acelerar a incorporação e a compreensão das lesões. Este artigo descreve várias formas que são usadas na descrição de lesões em patologia veterinária.(AU)

Shapes of pathology / As formas da patologia

The shape is one of the key features of a lesion and a pathologist must be able to identify and interpret these forms in the context of any gross and microscopic changes. One of the principles of adult learning is to engage the learner with previously understood information. If, when presenting material that is new, a connection with something the student already has familiarity with, the learning process is accelerated. As the learners are already familiar with shapes they have encountered throughout their pre-pathology learning, these can be used to hasten the incorporation and understanding of lesions. This paper describes various shapes that are used in describing lesions in veterinary pathology.(AU)

A forma é uma das principais características de uma lesão. Um patologista deve ser capaz de identificar e interpretar essas formas no contexto de quaisquer alterações macroscópicas ou microscópicas. Um dos princípios da aprendizagem de adultos é envolver o aluno com informações previamente compreendidas. Se, ao apresentar um material novo, se estabelece uma conexão com algo que o aluno já conhece, o processo de aprendizagem torna-se mais rápido e eficiente. Como os alunos já estão familiarizados com as formas que encontraram ao longo de sua aprendizagem pré-patologia, elas podem ser usadas para acelerar a incorporação e a compreensão das lesões. Este artigo descreve várias formas que são usadas na descrição de lesões em patologia veterinária.(AU)

Primary bone neoplasms in dogs: 90 cases / Neoplasmas ósseos primários em cães: 90 casos

A retrospective study of necropsy and biopsy cases of 90 primary bone tumors (89 malignant and one benign) in dogs received over a period of 22 years at the Laboratório de Patologia Veterinária, Universidade Federal de Santa Maria, was performed. Osteosarcoma was the most prevalent bone tumor, accounting for 86.7% of all malignant primary bone neoplasms diagnosed. Most cases occurred in dogs of large and giant breeds with ages between 6 and 10-years-old. The neoplasms involved mainly the appendicular skeleton, and were 3.5 times more prevalent in the forelimbs than in the hindlimbs. Osteoblastic osteosarcoma was the predominant histological subtype. Epidemiological and pathological findings of osteosarcomas are reported and discussed.(AU)

Através de um estudo retrospectivo dos casos de biópsias e necropsias de cães recebidos no Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria, num período de 22 anos, constatou-se a ocorrência de 90 casos de neoplasmas ósseos primários, sendo 89 malignos e um benigno. Dentre os 89 neoplasmas ósseos malignos, osteossarcoma foi o mais prevalente, correspondendo a 86,7% de todos o neoplasmas ósseos diagnosticados na espécie. A maioria dos casos ocorreu em cães de raças grandes e gigantes e entre seis e 10 anos de idade. Os neoplasmas envolvendo o esqueleto apendicular predominaram e foram 3,5 vezes mais prevalentes nos membros anteriores que nos posteriores. O subtipo histológico predominante foi o osteoblástico. Este estudo aborda os aspectos epidemiológicos e patológicos importantes para o diagnóstico de osteossarcomas.(AU)

Primary brain T-cell lymphoma in a cat

A 10-year-old, female, mixed-breed cat was presented for necropsy with history of incoordination, circling and nystagmus or fixed gaze. Grossly, slight asymmetry was observed in the right telencephalic hemisphere, mainly in the pyriform lobe. Histologically, sheets of small round neoplastic cells were observed in the pons, midbrain, thalamus and in the subcortical white matter of the parietal, occipital and pyriform lobes. Neoplastic cells were strongly labeled with anti-CD3 antibody by means of immunohistochemistry. Anti-BLA36, CD79a and MAC387 failed to label the neoplastic cells. Based on the histopathological findings and on the immunohistochemical results, a diagnosis of primary brain T-cell lymphoma was made.

Primary brain T-cell lymphoma in a cat

A 10-year-old, female, mixed-breed cat was presented for necropsy with history of incoordination, circling and nystagmus or fixed gaze. Grossly, slight asymmetry was observed in the right telencephalic hemisphere, mainly in the pyriform lobe. Histologically, sheets of small round neoplastic cells were observed in the pons, midbrain, thalamus and in the subcortical white matter of the parietal, occipital and pyriform lobes. Neoplastic cells were strongly labeled with anti-CD3 antibody by means of immunohistochemistry. Anti-BLA36, CD79a and MAC387 failed to label the neoplastic cells. Based on the histopathological findings and on the immunohistochemical results, a diagnosis of primary brain T-cell lymphoma was made.(AU)

Transmission and pathogenesis of vesicular stomatitis viruses

Vesicular Stomatitis (VS) is caused by Vesicular stomatitis viruses (VSV), negative single stranded RNA arthropod-borne members of the Family Rhabdoviridae. The VSV virion is composed of the host derived plasma membrane, the envelope, and an internal ribonucleoprotein core. The envelope contains a transmembrane glycoprotein, the G protein, which mediates viral entry and exit from the cell. The ribonucleoprotein core contains the viral genome encased within the nucleocapsid protein, the N protein. The large protein (L), the nucleocapsid (N) and the phosphoprotein (P) have key roles in viral replication. The matrix protein (M protein), located between the envelope and the nucleocapsid core participates in viral assembly, and particle budding. The VSV serotypes involved with disease in livestock are New Jersey and Indiana 1, 2 and 3. Serotypes New Jersey and Indiana 1 occur from USA through Central America to much of South America. Serotype Indiana 3 (or Alagoas) occurs in the North, Northeast and Central Brazil. The serotype Indiana 2 (or Cocal), occurs in Southern Brazil and in Argentina. Outbreaks of VS in Brazil in recent years have resulted in severe economic losses. The clinical disease in horses, cattle, and pigs is characterized by vesicles in tongue, planum nasale, planum rostrale, coronary bands (CB) of the feet, prepuce, and teats. Subclinical disease, with seroconversion and lack of on of vesicle formation is common under natural conditions and can be induced experimentally depending on the site inoculation. VSV infection typically involves cytolytic infection of mammalian host cells at specific sites of inoculation. Transmission can occur via infected insect bite but animal-to-animal contact could also be important in within-herd spread. There is some evidence to suggest that biting insects may play a role in the pathogenesis of VSV infection, although mechanisms of pathogenesis are not well understood. Viral spread seems to stop at the draining lymph nodes with no viremia. As a well-known in vitro producer of interferon, it is hypothesized that the host immune response to VSV infection may limit viral spread. A better understanding of pathogenic aspects could allow development of prevention and disease control strategies.

Detection of reticuloendotheliosis virus by immunohistochemistry and in situ hybridization in experimentally infected chicken embryo fibroblasts

Reticuloendotheliosis virus (REV) infection can result in immunosuppression, runting syndrome, high mortality, acute reticular cell neoplasia, or T- and/or B-cell lymphoma, in a variety of domestic and wild birds. Histopathological changes of reticuloendotheliosis (RE) are not sufficient to differentiate it from Avian Leukosis (AL) and Marek's disease (MD). Currently there available diagnostic methods for detection of active REV infection. In order to develop immunohistochemistry (IHC) and in situ hybridization (ISH) assays for detection of REV active infections, experimentally inoculated formalin-fixed and paraffin embedded DF-1 chicken embryo fibroblasts were used as an infection model. IHC and ISH assays proved to be efficient for the detection of several REV strains, and to differentiate those strains from representative strains of the avian leukosis/sarcoma group of retroviruses (ALSV).

Febre catarral maligna em bovinos no Rio Grande do Sul: transmissão experimental para bovinos e caracterização do agente etiológico / Malignant catarrhal fever in cattle in Rio Grande do Sul, Brazil: experimental transmission to cattle and characterization of the etiological agent

São relatados dois surtos de febre catarral maligna (FCM) em bovinos de duas propriedades rurais (A e B) do município de Santiago, Rio Grande do Sul (RS), a transmissão da doença a bovinos suscetíveis e a detecção de DNA viral de herpesvírus bovino-2 (OvHV-2) em tecidos de bovinos afetados. Os dois surtos ocorreram de novembro de 2001 a fevereiro de 2002 (Propriedade A) e de janeiro a fevereiro de 2003 (Propriedade B). O número de bovinos sob risco, as taxas de morbidade e de letalidade foram, respectivamente, 170, 10,59 por cento e 83,33 por cento na Propriedade A e 500, 2,4 por cento e 100 por cento na Propriedade B. Em ambas as propriedades havia contato de ovinos com os bovinos afetados, mas somente na Propriedade A havia ovelhas em parição. Nos bovinos afetados nas duas propriedades, a duração do curso clínico, os achados de necropsia e a histopatologia foram semelhantes. A maioria dos bovinos afetados morreu ou foi submetida à eutanásia in extremis após um curso clínico de 2 a 8 dias. Os sinais clínicos incluíam febre (40,5 e 41,5ºC), corrimento nasal e ocular, opacidade da córnea, conjuntivite, salivação, erosões e ulcerações em mucosas, diarréia, hematúria e distúrbios neurológicos. Foram realizadas onze necropsias...(AU)

Two oubreaks of malignant catarrhal fever (MCF) occurring in cattle on two farms (A and B) in the municipality of Santiago, state of Rio Grande do Sul (RS), Brazil, and the transmission of the disease to susceptible calves as well as the detection of ovine herpesvirus-2 (OvHV-2) in tissues of affected cattle are reported. The two epizootics occurred from November 2001 to February 2002 (Farm A) and in January-February 2003 (Farm B). Numbers of cattle at risk, morbidity and letality rates were respectively 170, 10.59% and 83.33% for Farm A and 500, 2.4% and 100% for Farm B. Contact between affected cattle and sheep was detected in both farms, but lambing ewes were present only in farm A. Duration of clinical courses, gross findings and histopathology were the same for the affected cattle in both farms. Most affected cattle died or were euthanatized in extremis after a clinical course of 2-8 days. Clinical signs included fever (40.5 and 41.5°C), nasal and ocular discharge, corneal opacity, conjunctivitis, drooling, erosions and ulcerations of the mucosae, diarrhea, hematuria, and neurological disturbances. Eleven necropsies (9 on Farm A, 2 on Farm B) were performed. Gross lesions included erosions and ulcers affecting the mucosae of nasal turbinates, oral cavity, gastrointestinal and urogenital tracts; hemorrhage and necrosis of the tip of the buccal papillae, lymph node enlargement, multifocal white foci in renal cortex, and hyperemia of leptomeninges. Microscopically, there were arteritis and fibrinoid degeneration in medium and small arteries and arterioles of multiple organs and tissues, necrosis and inflammation in several mucosal surfaces, keratitis, conjunctivitis, uveitis, intersticial nephritis, and encephalitis. Transmission experiments were attempted in five calves (E1-E5) by inocculating each of them intravenously with 500 ml of whole heparinized blood from a MCF affected cow. The transmission was suscessful in at least three (E1-E3) ... (AU)