Thyroid lesions in a population of domestic cats submitted to necropsy without clinical suspicion of thyroid disease.

Although hyperthyroidism is the most common endocrine disorder in elderly cats, systematic studies investigating the prevalence of thyroid lesions in feline animals are scarce. Our objective was to evaluate morphological changes in the thyroid glands of 61 cats submitted to necropsy without clinical suspicion of hyperthyroidism. Thirteen (13/61 [21.3%]) cats had thyroid enlargement and 54/61 (88.5%) had some histological thyroid changes. Proliferative lesions were histologically seen in 33/61 (54%) cats while non-proliferative lesions were observed in 48/61 (78.7%) cats. Thyroid hyperplasia (18/33 [54.5%]) and cystic adenoma (6/33 [18.2%]) were the most prevalent proliferative changes and lesions with little or no clinical significance (37/61 [60.6%]), degenerative (31/61 [50.8%]) and inflammatory changes (12/61 [19.7%]) were the most common non-proliferative changes. Among cats with proliferative lesions, 16/33 (48.4%) had a proliferation grade ≥A4, a grade previously associated with clinical hyperthyroidism. Although the cats from this study did not have any clinical diagnosis of thyroid disease, it is possible that one or more had some degree of clinically unnoticed thyroid dysfunction. The high prevalence of follicular lesions in this study highlights the importance of a more careful clinical and pathological investigation regarding thyroid diseases in mature and elderly cats.

Detection of Equus caballus papillomavirus-2 in equine penile/preputial papillomas and squamous cell carcinomas in southern Brazil.

For approximately one decade, a novel papillomavirus termed Equus caballus papillomavirus-2 (EcPV-2) has been associated with equine penile/preputial papillomas and squamous cell carcinomas (SCCs). It is currently believed that the virus has a carcinogenic activity, being able to induce such neoplastic lesions. After being first described, EcPV-2 has been detected in many countries from North America, Europe, and Asia; however, to date, it has not been reported in Brazil. The aim of this research was to investigate the presence of EcPV-2 in penile/preputial papillomas and SCCs of Brazilian horses. Forty samples diagnosed as equine penile and/or preputial papillomas, carcinomas in situ (CIS), or SCCs in two veterinary anatomic pathology services from southern Brazil were investigated. Histologic evaluation and immunohistochemistry (IHC) using a BPV-1 antibody were performed. Posteriorly, the samples were submitted to polymerase chain reaction using two broad-spectrum (MY09/11 and FAP) and one EcPV-2-specific primer sets. Positive samples were sequenced. PV antigen expression was detected in one papilloma, one CIS, and two SCCs by IHC. Five SCCs, one papilloma, and one CIS were PV-positive on PCR. Sequencing of the seven PCR products revealed homology with EcPV-2. This study confirms the occurrence of EcPV-2 infection in Brazilian horses. Moreover, the results presented here provide useful information concerning the phylogeny from the viruses detected in our samples. We hope to encourage further studies on this novel agent, contributing to its characterization, and, possibly, to the eventual development of preventive measurements, including a possible vaccine.

Sinonasal neoplasms in 49 dogs: clinical, macroscopic, and histopathological aspects / Neoplasmas nasossinusais em 49 cães: aspectos clínicos, macroscópicos e histopatológicos

This study aimed to quantify nasosinusal neoplasms diagnosed in dogs in 20 years (2000-2019) and characterize the main clinical, macroscopic, and histological aspects of these neoplasms. The sex, breed, age, skull conformation, the main clinical signs, and the anatomopathological characteristics (distribution, macroscopy, and histology) were computed. During this period, 49 dogs were affected by neoplasms in these regions, totaling 50 neoplasms (one dog had two neoplasms of different locations and histogenetic origins). Similar amounts of mixed-breed dogs (25/49) and purebred dogs (24/49) were affected, these distributed in 16 breeds. Among purebreds, it was noted that dogs with mesocephalic cranial conformation (12/24) were the most affected, followed by dolichocephalic (10/24) and brachycephalic (2/24). There were 22 cases in males and 27 in females, making a proportion of 1:1.23. There was an age variation from 11 months to 16 years old. The epithelial neoplasms have occurred in older dogs compared to those of other histogenic origins (mesenchymal and other origins/round cells). The main clinical signs were similar between the histogenetic categories, related to the involvement of the upper respiratory tract, sometimes accompanied by nervous signs (when there was brain invasion of nasal neoplasms or vice versa). The possible origin site was mostly in the nasal cavity concerning the paranasal sinuses (and other locations). Invasions occurred in different tissues adjacent to the nasal cavity and paranasal sinuses, resulting in cranial and facial deformities (21/49). The frequency was 48% of epithelial neoplasms, 32% of mesenchymal neoplasms, and 10% of neoplasms with other origins and round cells. The neoplasms most frequently observed, in decreasing order of frequency, were: adenocarcinoma (9/50), squamous cell carcinoma (9/50), transmissible venereal tumor (5/50), osteosarcoma (5/50), chondrosarcoma (4/50), and undifferentiated sarcoma (4/50). Through this study, it was possible to establish the frequency of these neoplasms in 20 years and their clinical, macroscopic, and histological characteristics.(AU)

Este estudo teve como objetivo quantificar os neoplasmas nasossinusais diagnosticados em cães em 20 anos (2000-2019) e caracterizar os principais aspectos clínicos, macroscópicos e histológicos desses neoplasmas. Foram computados sexo, raça, idade, conformação do crânio, principais sinais clínicos e características anatomopatológicas (distribuição, macroscopia e histologia). Nesse período, 49 cães foram acometidos por neoplasmas nessas regiões, totalizando 50 neoplasmas (um cão tinha dois neoplasmas de localização e origens histogenéticas distintas). Foram acometidas quantidades semelhantes de cães sem raça definida (25/49) e de cães com raça definida (24/49), estes distribuídos em 16 raças. Entre os cães com raça definida, notou-se que os cães com conformação craniana mesocefálica (12/24) foram os mais acometidos, seguidos pelos dolicocefálicos (10/24) e braquicefálicos (2/24). Foram observados 22 casos em machos e 27 em fêmeas, perfazendo a relação de 1:1,23. Ocorreu uma variação de idade de 11 meses a 16 anos; tendo os neoplasmas epiteliais ocorrido em cães mais velhos quando comparado aos de outras origens histogênicas (mesenquimais e outras origens/células redondas). Os principais sinais clínicos foram semelhantes entre as categorias histogenéticas, sendo relacionados ao comprometimento do trato respiratório superior, por vezes acompanhados de sinais nervosos (quando houve invasão encefálica de neoplasmas nasais ou vice-versa). O possível local de origem em sua maioria foi na cavidade nasal em relação aos seios nasais (e de outras localizações). Ocorreram invasões para diferentes tecidos adjacentes à cavidade nasal e seios paranasais, tendo como consequência deformidades cranianas e faciais (21/49). A frequência foi de 48% de neoplasmas epiteliais, 32% de neoplasmas mesenquimais e 10% de neoplasmas com outras origens e de células redondas. Os neoplasmas mais frequentemente observados, em ordem decrescente de frequência, foram: adenocarcinoma (9/50), carcinoma de células escamosas (9/50), tumor venéreo transmissível (5/50), osteossarcoma (5/50), condrossarcoma (4/50) e sarcoma indiferenciado (4/50). Com isso, pode-se estabelecer a frequência desses neoplasmas em 20 anos, bem como suas características clínicas, macroscópicas e histológicas.(AU)

Testicular tumors in 190 dogs: clinical, macroscopic and histopathological aspects / Neoplasmas testiculares em 190 cães: aspectos clínicos, macroscópicos e histopatológicos

This study aimed to characterize the prevalence and clinical, macroscopic and histopathological aspects of dogs affected by testicular tumors based on biopsy specimens from the Laboratório de Patologia Veterinária of the Universidade Federal de Santa Maria (LPV-UFSM) over 19 years. Parameters regarding the age, size, and breed of the affected dogs were also established. Of all dogs with some type of neoplasm submitted to histopathological analysis at the LPV over these 19 years (n=1,900), 213 (11.2%) had at least one testicular neoplasm. The tissues of 190 dogs (with 220 neoplasms) were available for histological reassessment. The dogs in this study had different types of testicular tumors with relatively similar frequencies. In descending order, the most frequent testicular neoplasms were seminomas (88/220), Leydig (interstitial) cell tumor (LCT; 64/220), Sertoli cell tumor (SCT; 61/220), and mixed germ cell-sex cord stromal tumor (MGSCT) (07/220). Among the dogs of defined breed (119 cases), large breeds had the largest number of cases (50/119), followed by small (47/119) and medium-sized (22/119) breeds. The ages of dogs affected by testicular tumors ranged from 10 months to 18 years. Increased testicular volume was the most common clinical manifestation. Eleven dogs presented information about clinical signs suggestive of hyperestrogenism syndrome (feminization). In seminomas, the diffuse pattern predominated over the intratubular pattern. Two sites (luminal and basal compartments) suggestive of the onset of neoplastic transformations in germ cells were observed in intratubular seminomas. They corroborate the hypothesis that canine seminomas possibly have pathogenesis similar to that observed in human spermatocytic seminomas. The SCTs and LCTs presented high cell morphology variation. SCTs had neoplastic cells organized in five different histological arrangements. As for LCT, solid-diffuse and cystic-vascular histological patterns were the most commonly observed. Through this study, it was possible to establish some of the leading clinical, macroscopic, and histopathological aspects of testicular neoplasms diagnosed over 19 years in the area covered by the LPV-UFSM.(AU)

Este estudo teve por objetivo caracterizar a prevalência, aspectos clínicos, macroscópicos e histopatológicos dos cães acometidos por neoplasmas testiculares, a partir dos espécimes de biópsias do Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria (LPV-UFSM) em 19 anos. Parâmetros quanto à idade, porte, raça dos cães acometidos também foram estabelecidos. De todos os cães com algum tipo de neoplasma submetido à análise histopatológica no LPV nesses 19 anos (n=1.900), 213 (11,2%) tinham ao menos um neoplasma testicular. Os tecidos de 190 cães (com 220 neoplasmas) estavam disponíveis para reavaliação histológica. Os cães deste estudo apresentaram diferentes tipos de neoplasmas testiculares com frequências relativamente semelhantes. Em ordem decrescente, os neoplasmas testiculares mais frequentes foram: seminomas (88/220), leydigomas (64/220), sertoliomas (61/220) e o tumor misto de células germinativas e do estroma do cordão sexual (MGSCT; 07/220). Dentre os cães com raça definida (119 casos), as raças de grande porte tiveram o maior número de casos (50/119), seguido das raças de pequeno (47/119) e médio porte (22/119). As idades dos cães acometidos por neoplasmas testiculares variaram de 10 meses a 18 anos. Aumento de volume testicular foi a manifestação clínica mais comum. Onze cães tinham informações sobre sinais clínicos sugestivos da síndrome da feminilização. Nos seminomas, houve o predomínio do padrão difuso sobre o intratubular. Dois locais (compartimentos luminal e basal) sugestivos de início das transformações neoplásicas nas células germinativas foram observados nos seminomas intratubulares, corroborando com a hipótese de que os seminomas caninos possivelmente tem patogênese semelhante à observada nos seminomas espermatocíticos humanos. Sertoliomas e leydigomas foram neoplasmas com alta variação na morfologia celular. Os sertoliomas tinham células neoplásicas dispostas em cinco arranjos histológicos distintos. Quanto aos leydigomas, os padrões histológicos sólido-difuso e cístico-vascular foram os mais comumente observados. Através deste estudo foi possível estabelecer alguns dos principais aspectos clínicos, macroscópicos e histopatológicos dos neoplasmas testiculares diagnosticados em 19 anos na área de abrangência do LPV-UFSM.(AU)

A retrospective histologic study of 140 cases of clinically significant equine ocular disorders.

Ocular diseases are an important category in equine medicine; however, most articles regarding histologic ocular lesions in horses are exclusive to a specific condition and do not provide a complete review of clinically significant ocular disease frequency in a diagnostic laboratory. We reviewed sections of equine eyes from 140 cases (98 enucleations [biopsies] and 42 autopsies) with clinically relevant ocular alterations at 2 diagnostic centers in the United States. The most common primary conditions were non-traumatic keratitis (36), equine recurrent uveitis (ERU; 31), traumatic injuries (22), ocular and periocular neoplasms (19), and uveitis and/or endophthalmitis resulting from sepsis (18). Congenital anomalies (3) and retinal atrophy and detachment alone (3) were infrequent. Non-traumatic keratitis was frequently accompanied by anterior uveitis (22), corneal rupture (16), pre-iridal fibrovascular membrane formation (13), and secondary mycotic infection (11). ERU was the second and third most prevalent disease in autopsies and enucleations, respectively. This condition was commonly associated with glaucoma (15). Glaucoma (25) and cataract (20) were the most prevalent secondary alterations in the evaluated cases. Keratitis (20) and corneal rupture (16) were among the most prevalent consequences of trauma. Information presented herein may guide clinicians and pathologists, contributing to the early diagnosis of potentially vision-impairing conditions and raising the chances of successful treatment and cure.

Ganciclovir attenuates the respiratory disease induced by Equid alphaherpesvirus 1 in rabbits / O ganciclovir atenua a doença respiratória produzida pelo alfaherpesvírus equino 1 em coelhos

Equid alphaherpesvirus 1 (EHV-1) is an important pathogen of horses, associated with respiratory, neurological disease and abortions. As vaccination is not always effective, anti-herpetic therapy may represent an alternative to prevent the losses caused by the infection. We herein investigated the activity of ganciclovir (GCV), an anti-herpetic human drug, in rabbits experimentally infected with EHV-1. Thirty-days-old New Zealand rabbits were allocated in three groups (6 animals each) and submitted to different treatments: G1 (non-infected controls), G2 (inoculated with EHV-1) - 107 TCID50 intranasally - IN) and G3 (inoculated IN with EHV-1 and treated with GCV - 5mg/kg/day for 7 days) and monitored thereafter. All animals of G2 developed systemic signs (moderate to severe apathy, anorexia), ocular discharge and respiratory signs (serous to mucopurulent nasal discharge), including mild to severe respiratory distress. Viremia was detected in all rabbits of G2 for up to 11 days (mean duration = 6.5 days). One animal died after severe respiratory distress and neurological signs (bruxism, opistotonus). In addition, these animals gained less weight than the control (G1) and GCV-treated rabbits (G3) from days 4 to 14pi (p<0.05). The clinical score of rabbits of G2 was statistically higher than the other groups from days 3 to 6pi (p<0.05), demonstrating a more severe disease. In contrast, G3 rabbits did not present systemic signs, presented only a mild and transient nasal secretion and gained more weight than G2 animals (p<0.05). In addition, viremia was detected in only 3 rabbits and was transient (average of 2.3 days). Thus, administration of GCV to rabbits inoculated IN with EHV-1 resulted in an important attenuation of the clinical disease as demonstrated by full prevention of systemic signs, maintenance of weight gain and by drastic reduction in viremia and in the magnitude of respiratory signs. These results are promising towards further testing of GCV as a potential drug for anti-herpetic therapy in horses.(AU)

O alfaherpesvírus equino 1 (EHV-1) é um importante patógeno de equinos, associado com doença respiratória, neurológica e abortos. Como a vacinação nem sempre é eficaz, a terapia anti-herpética pode representar uma alternativa para prevenir as perdas causadas pela infecção. Para tal, investigou-se a atividade do ganciclovir (GCV), uma droga anti-herpética de uso humano, em coelhos infectados experimentalmente com o EHV-1. Coelhos da raça Nova Zelândia com 30 dias de idade foram alocados em três grupos (6 animais cada) e submetidos a diferentes tratamentos: G1 (controles não infectados), G2 (inoculados com o EHV-1) - 107 TCID50 intranasal - IN) e G3 (inoculados IN com o EHV-1 e tratados com GCV - 5mg/kg/dia por 7 dias), e monitorados posteriormente. Todos os animais do G2 desenvolveram sinais sistêmicos (apatia moderada a grave, anorexia), secreção ocular e sinais respiratórios (secreção nasal serosa a mucopurulenta), incluindo dificuldade respiratória leve a grave. Viremia foi detectada em todos os coelhos do G2 por até 11 dias (duração média = 6,5 dias). Um animal morreu após dificuldade respiratória grave e sinais neurológicos (bruxismo, opistótono). Além disso, esses animais ganharam menos peso que os coelhos controle (G1) e tratados com GCV (G3) entre os dias 4 e 14pi (p<0,05). O escore clínico de coelhos do G2 foi estatisticamente maior que os demais grupos dos dias 3 a 6pi (p<0,05), demonstrando uma doença mais grave. Em contraste, os coelhos do G3 não apresentaram sinais sistêmicos, apresentaram apenas secreção nasal leve e transiente e ganharam mais peso que os animais do G2 (p<0,05). Além disso, a viremia foi detectada em apenas 3 coelhos e foi transitória (média de 2,3 dias). Assim, a administração de GCV a coelhos inoculados com EHV-1 resultou em uma importante atenuação da doença clínica, como demonstrado pela prevenção completa de sinais sistêmicos, manutenção do ganho de peso e pela redução drástica da viremia e da magnitude dos sinais respiratórios. Estes resultados são promissores para testes adicionais com o GCV para potencial terapêutico anti-herpética em equinos.(AU)

Use of different fixation times and application of two immunohistochemical methods for detection of KIT and Ki67 proteins in canine cutaneous mast cell tumors / Utilização de diferentes tempos de fixação e métodos imuno-histoquímicos na detecção das proteínas KIT e Ki67 em mastocitomas cutâneos caninos

Due to the high prevalence of mast cell tumors (MCTs) in the diagnostic routine, several factors, especially prognostic, have been sought to determine the biological behavior of these neoplasms. Immunohistochemistry (IHC) is one of the main tools utilized to biologically differentiate more aggressive tumors from less aggressive ones. However, some immunostainings are influenced by formalin fixation, interfering with the results. This is both a retrospective and prospective study of MCTs diagnosed in laboratory routine. A total of 25 samples, without knowledge about fixation time, were analyzed in the retrospective study, whereas 12 samples, with known fixation times, were assessed in the prospective study. Two histologic grading systems (Patnaik and Kiupel), special staining of toluidine blue, and IHC for KIT and Ki67 proteins were applied in both studies. Additionally, two amplification systems (biotinylated and non-biotinylated) for Ki67 protein and counting of the argyrophilic nucleolar organizing regions (AgNOR method) were tested in the prospective study. In the retrospective study, greater agreement between the evaluating pathologists was observed when the Kiupel system was used. IHC staining for KIT protein was effective in both studies, regardless of fixation time. IHC staining for Ki67 protein was highly sensitive to formaldehyde, and staining failure was observed in 56% of the cases in the retrospective study. In the prospective study, samples fixed for longer than 24 hours showed a reduction in the number of stained cells (altering the determination of the cell growth fraction) or showed absence of IHC staining in both amplification systems. The use of the AgNOR method to evaluate the rate of cell proliferation may be an alternative when the fixation time of the neoplasm is unknown or longer than 24 hours.(AU)

Devido a alta prevalência dos mastocitomas cutâneos caninos (MCCs) na rotina diagnóstica, vários fatores, especialmente fatores prognósticos, têm sido buscados para auxiliar na determinação do comportamento biológico desse neoplasma. A imuno-histoquímica é uma das principais ferramentas empregadas para diferenciar tumores biologicamente mais agressivos de tumores menos agressivos. Entretanto, algumas imunomarcações sofrem influência pela fixação em formol, interferindo nos resultados. Este estudo compreendeu avaliar através de uma etapa retrospectiva e uma etapa prospectiva casos de MCCs diagnosticados na rotina laboratorial. Um total de 25 amostras, sem conhecimento do tempo de fixação, foi analisado no estudo retrospectivo e 12 amostras, com tempos de fixação conhecidos, no estudo prospectivo. Foram aplicados nos dois estudos, dois sistemas de graduação histológica (Patnaik e Kiupel), a coloração especial de azul de toluidina e a imuno-histoquímica para as proteínas KIT e Ki67. Adicionalmente, no estudo prospectivo, foram testados dois sistemas de amplificação (biotinilado e não biotinilado) para a proteína Ki67 e a técnica de AgNOR (contagem das regiões organizadoras nucleolares argirofílicas). Na etapa retrospectiva, observou-se uma maior concordância entre os patologistas avaliadores quando o sistema Kiupel foi utilizado. A imunomarcação para KIT se manteve eficaz em ambos os estudos, independentemente do tempo de fixação. A imunomarcação para o Ki67 mostrou-se altamente sensível ao tempo de fixação em formol, sendo observada falha na imunomarcação em 56% dos casos do estudo retrospectivo. No estudo prospectivo, constatou-se que amostras fixadas por mais de 24 horas em formol apresentaram redução na quantidade de células imunomarcadas (alterando a determinação da fração de crescimento celular) ou apresentaram ausência de imunomarcação em ambos os sistemas de amplificação. A utilização do método AgNOR, para avaliar a taxa de proliferação celular, pode ser uma alternativa quando o tempo de fixação do neoplasma for desconhecido ou superior a 24 horas.(AU)

Mielodisplasia na peritonite infecciosa felina: 16 casos (2000-2017) / Myelodysplasia in feline infectious peritonitis: 16 cases (2000-2017)

Apesar da prevalência da peritonite infecciosa felina (PIF) ser alta em praticamente o mundo todo, estudos anatomopatológicos recentes acerca dessa doença são escassos. Não obstante, as características microscópicas da medula óssea de gatos com PIF estão ausentes da literatura consultada. O objetivo deste artigo é descrever alterações medulares ósseas vistas em casos espontâneos de PIF. As medulas ósseas colhidas sistematicamente da região diafisária dos fêmures de 16 gatos necropsiados no Laboratório de Patologia Veterinária (LPV) da Universidade Federal de Santa Maria (UFSM), Rio Grande do Sul, entre janeiro de 2000 e junho de 2017, e que tiveram diagnóstico definitivo de PIF, foram avaliadas fenotípica (histopatologia - hematoxilina e eosina e histoquímica - reação de Perls) e imunofenotipicamente (utilizando marcadores mieloides (anti-MAC387) e de linfócitos (anti-CD79αcy e anti-CD3). Os resultados permitem afirmar que, independentemente da apresentação clinicopatológica da doença ocorrem as seguintes alterações: 1) hiperplasia mieloide; 2) hipoplasia eritroide, 3) displasia megacariocítica (dismegacariocitopoiese) e 4) plasmocitose medular. Exclusivamente nos casos de PIF seca há hemossiderose medular óssea e hepática. Essas alterações permitem estabelecer que gatos com PIF desenvolvem mielodisplasia, uma lesão mieloproliferativa muito semelhante àquela relatada em humanos infectados pelo HIV. Sugere-se que a partir dos achados aqui descritos, a mielodisplasia seja considerada a principal responsável pelas alterações hematológicas observadas na PIF, especialmente pela anemia e trombocitopenia arregenerativas frequentemente desenvolvidas pelos pacientes com essa doença.(AU)

Although the prevalence of feline infectious peritonitis (FIP) is high worldwide, recent anatomopathological studies about this disease are scarce. Information on the microscopic characteristics of the bone marrow in FIP-affected cats are absent in the available literature. Based on this, the purpose of this article is to describe bone marrow lesions seen in spontaneous cases of FIP. The bone marrow collected systematically from the femoral diaphysis of 16 cats necropsied in the Laboratory of Veterinary Pathology (LPV) of the Federal University (UFSM) of Southern Brazil, between January 2000 and June 2017, with a definitive diagnosis of FIP, were evaluated phenotypically (histopathology - hematoxylin and eosin and histochemistry - Perls stain) and immunophenotypically (immunohistochemistry using myeloid - Anti-MAC387, and lymphocytic - Anti-CD79 αcy and Anti-CD3 markers). Regardless the following was observed the clinicopathological form of the disease ("dry" - noneffusive or "wet" - effusive): 1) myeloid hyperplasia; 2) erythroid hipoplasia; 3) megakaryocytic dysplasia (dismegakaryocytopoiesis); and 4) medullary plasmacytosis. Exclusively in cases of "dry FIP" was bone marrow and hepatic hemosiderosis. These lesions allowed establishing that cats with FIP develop myelodysplasia, a myeloproliferative lesion very similar to that reported in HIV-infected humans. It is suggested that, based on the findings described here, myelodysplasia is considered to be the main cause of hematological abnormalities observed in FIP, especially for non-regenerative anemia and thrombocytopenia, frequently developed by patients.(AU)

Caracterização do gênero, da raça e da idade de uma população de 7. 780 cães da Região Central do Rio Grande do Sul submetidos à necropsia ao longo de cinco décadas (1964-2013) / Characterization of gender, breed and age in a population of 7. 780 dogs submitted for necropsy over five decades (1964-2013) in central Rio Grande do Sul, Brazil

Devido à ausência de um banco de dados demográficos da população canina que habita a Região Central do Rio Grande do Sul (RS) e à necessidade em se estabelecer uma "população controle" para a melhor interpretação da prevalência das doenças diagnosticadas pelo Laboratório de Patologia Veterinária (LPV-UFSM) da Universidade Federal de Santa Maria (UFSM), este estudo objetivou realizar uma análise das características relacionadas à raça, ao gênero e à idade dos cães necropsiados neste serviço de diagnóstico ao longo de 50 anos (1964-2013). Para isto, os laudos de necropsias de cães, realizadas entre 1964 e 2013, foram revisados, e deles foram retiradas informações referentes ao gênero, à idade e às raças de todos os cães oriundos dos municípios que compõem a Região Central do RS. Ao todo, 7.780 cães foram necropsiados; desses, 469 (6%) na primeira década (1964-1973), 1.133 (14,6%) na segunda década (1974-1983), 1.334 (17,1%) na terceira década (1984-1993), 1.705 (22%) na quarta década (1994-2003) e 3.139 (40,3%) na quinta década (2004-2013). Do total de cães com gênero informado nos laudos, 52,6% eram machos e 47,4% eram fêmeas. A mediana da idade de morte foi de três anos. Dos cães cuja raça foi informada nos laudos, 59,8% eram de raça definida (RD) e 40,2% não tinham raça definida (SRD). As raças de porte grande ou gigante mais frequentes foram: Pastor Alemão (17,2%), Boxer (6,9%), Rottweiler (5,3%), Fila Brasileiro (4,6%), Pointer Inglês (3,9%), Collie Pelo Longo (3,7%) Dobermann (3,7%) e Labrador Retriever (2,1%). As raças de porte pequeno ou médio mais frequentes foram: Poodle (8,9%), Dachshund (6,3%), Pinscher Miniatura (5,6%), Cocker Spaniel Inglês (4,5%), Pequinês (3,4%), Yorkshire Terrier (3,3%) e Terrier Brasileiro (2,8%). Houve um aumento na proporção de fêmeas e um crescimento na mediana referente à idade de morte ao longo das cinco décadas avaliadas. Apesar de não ter havido um aumento relevante na proporção de cães de RD em comparação com os SRD, observaram-se algumas mudanças na ocorrência de diferentes raças ao longo do tempo, incluindo principalmente uma dramática diminuição na percentagem de Pequinês, Terrier Brasileiro, Pointer Inglês e Pastor Alemão, e um aumento marcado na percentagem de Poodle, Dachshund, Rottweiler e Labrador Retriever. Os resultados aqui apresentados servirão como um subsídio comparativo para futuros estudos retrospectivos sobre prevalência de doenças em cães da Região Central do RS, auxiliando para uma mais correta compreensão e interpretação dos resultados encontrados nesses levantamentos de dados.(AU)

Based on the lack of demographic database on the canine population living in the midland region of Rio Grande do Sul State, Brazil, and on the need for a "control population" in the accomplishment of several prevalence-based studies of different diseases diagnosed at the Laboratório de Patologia Veterinária (LPV) of the Universidade Federal de Santa Maria (UFSM), the objective of this study was to describe the breed, gender and age characteristics of the population of dogs necropsied in this diagnostic service over 50 years (1964-2013). The protocols of necropsies performed on dogs and recorded in the LPV-UFSM between 1964 and 2013 were reviewed, and information related to gender, age and breed from dogs from all the districts within the Central Region of RS were separated. A total of 7,780 dogs were necropsied, among which 469 (6%) were registered in the first decade (1964-1973), 1,133 (14.6%) in the second decade (1974-1983), 1,334 (17.1%) in the third decade (1984-1993), 1,705 (22%) in the fourth decade (1994-2003) and 3,139 (40.3%) in the fifth decade (2004-2013). Of dogs whose gender was reported in the protocols, 52.6% were males and 47.4% were females. The median age of death was 3 years. Of dogs whose breed was reported in the protocols, 59.8% were purebred and 40.2% were mixed breed. The most common large and giant breed dogs were German Shepherd Dog (17.2%), Boxer (6.9%), Rottweiler (5.3%), Fila Brasileiro (4.6%), English Pointer (3.9%), Collie Rough (3.7%), Dobermann (3.7%), and Labrador Retriever (2.1%). The most common small and medium breed dogs were Poodle (8.9%), Dachshund (6.3%), Miniature Pinscher (5.6%), English Cocker Spaniel (4.5%), Pekingese (3.4%), Yorkshire Terrier (3.3%), and Brazilian Terrier (2.8%). The percentage of females and the median age of death showed an increase during the five decades of this study. Although there has been a significant increase in the proportion of pure breed dogs compared to mongrels, we observed some changes in the occurrence of different breeds over time, including a significant decrease in the frequency of the Pekingese, Brazilian Terrier, English Pointer, and German Shepherd Dog, and significant increase in the frequency of the Poodle, Dachshund, and Labrador Retriever. The results presented here will serve as an allowance for future comparative studies of disease prevalence in dogs of Central Region of RS, helping to a more correct understanding and interpretation of results from these data surveys.(AU)

Serum and brain purine levels in an experimental systemic infection of mice by Cryptococcus neoformans: Purinergic immunomodulatory effects.

The aim of this study was to evaluate the purine levels in serum and brains of mice experimentally infected by Cryptococcus neoformans. Twenty-four mice were divided into the following groups: a control group (n = 12; Group A) and an infection group with animals that were infected (n = 12; Group B) with a 0.3-mL intraperitoneal injection containing 1.7 × 107C. neoformans cells. Blood and brains were collected on days 20 (n = 6 per group) and 50 (n = 6 per group) post-infection (PI). Histopathology and lung and brain cultures were performed to confirm fungal infection and tissue injuries. The levels of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), adenosine (ADO), inosine (INO), hypoxanthine (HYPO), xanthine (XAN) and uric acid (UA) in brains and serum were measured by high-performance liquid chromatography (HPLC) analysis. At both time points, histopathology analysis revealed inflammatory infiltrates in the brains and lungs of infected mice; clinical signs, such as piloerection and clinical respiratory distress, were also observed. ATP levels were significantly increased on days 20 and 50 PI (P < 0.01) in brains and serum, while brain ADO levels were increased on day 20 PI; brain and serum ADO levels were decreased on day 50 PI. Levels of ADP and AMP did not differ between groups (P > 0.05). Serum levels of INO of infected mice increased only on day 50 PI (P < 0.05). HYPO levels were reduced in the brains of infected animals at both experimental time points and were decreased in serum at day 50 PI (P < 0.05). XAN levels increased in infected mice only in serum on day 50 PI (P < 0.05). The endogenous anti-oxidant uric acid was significantly increased in brain (days 20 and 50 PI) and decreased in serum. It is possible that C. neoformans infection in mice leads to a high ATP/ADO ratio that may improve the brain pro-inflammatory response during both periods, while high ATP levels in serum act as a systemic signal to improve the immune response. Moreover, the anti-oxidant uric acid may increase in the brain to protect inflamed tissue from oxidative stress.

Participation of purines in the modulation of inflammatory response in rats experimentally infected by Cryptococcus neoformans.

The present study was carried out to assess the participation of purines in the activation and modulation of inflammatory response of rats experimentally infected by Cryptococcus neoformans. Twenty four Wistar rats were divided into two groups of 12 animals each: Group A - uninfected control group and Group B - infected by C. neoformans. Blood was collected 20 and 50 days post-infection (PI) from six animals of each group in order to verify purine levels (adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), adenosine (ADO), inosine (INO), hypoxanthine (HYPO), xanthine (XAN) and uric acid (URIC)). ATP levels were significantly increased (P < 0.05) in serum from infected animals on days 20 and 50 PI, as well as adenosine levels after 20 days PI on rats. On day 50 PI, levels of adenosine and uric acid were also reduced, but the levels of inosine and xanthine increased in animals infected by the fungus (P < 0.05). Therefore, it was possible to conclude that the purine levels in serum were altered and that these changes may be able to influence the pathogenesis of the disease caused by C. neoformans due the participation of purines (ATP and adenosine main) in the activation and modulation of inflammatory response.

Complex interaction of deferasirox and Pythium insidiosum: iron-dependent attenuation of growth in vitro and immunotherapy-like enhancement of immune responses in vivo.

Pythium insidiosum iron acquisition mechanisms are unknown. We previously showed that the iron chelator deferasirox had weak activity in vitro and in rabbits with experimental pythiosis. Here we show that deferasirox causes damage to P. insidiosum hyphae in vitro, but that activity is diminished in the presence of exogenous iron. The tissue activity of the proinflammatory enzyme adenosine deaminase and the histological pattern observed in pythiosis lesions of rabbits treated with deferasirox were similar to the ones in animals treated with immunotherapy.

E-NTPDase and E-ADA activities in rats experimental infected by Cryptococcus neoformans.

Cryptococcus neoformans, the etiological agent of cryptococcosis, is an opportunistic fungal pathogen of immunocompromised individuals. The aim of this study was to evaluate the activities of E-NTPDase and E-ADA in rats experimentally infected by C. neoformans var. grubii. Adult rats (35) were divided in two groups: 18 for the control group (uninfected) (A), and 17 for the infected group (B). Each group was separated into three sub-groups (A1, A2, A3-B1, B2, B3), and samples were collected on 10, 20, and 30 days post-infection (PI). Leukocyte counts, IFN-γ, TNF-α, IgM, IgG levels, and E-NTPDase and E-ADA activities were analyzed. It was possible to observe that IgG and IgM seric levels of infected rats were significantly elevated (P<0.01) on days 10, 20 and 30 PI, as well as the levels of TNF-α and INF-γ when compared to uninfected rodents. Regarding E-NTPDase activity in lymphocytes, it was possible to observe that the ATP hydrolysis was significantly decreased on days 20 (P<0.01) and 30 PI (P<0.05), while ADP hydrolysis was significantly reduced only on day 20 PI (P<0.01) when compared with uninfected group. Seric E-ADA activity had a significant reduction (P<0.01) during all three evaluated periods when compared to the control group, while E-ADA activity in lymphocytes increased significantly (P<0.01) when compared to the group A on day 10 PI; however on days 20 and 30 PI, its activity was considerable reduced in lymphocytes of infected animals (P<0.01). Therefore, it is possible to conclude that the infection caused by C. neoformans in immunocompetent rats leads to changes in the purinergic signaling (NTPDase and E-ADA), concomitantly with an inflammatory response (increased levels of cytokines and immunoglobulins) associated with inflammatory infiltrates and histological lesions in the lung.

Aspectos epidemiológicos, clínicos e anatomopatológicos da intoxicação por aceturato de diminazeno em cães / Epidemiological, clinical, and pathological aspects of diminazene aceturate toxicosis in dogs

Os aspectos epidemiológicos, clínicos e anatomopatológicos da intoxicação espontânea por aceturato de diminazeno foram estudados em 10 cães. Em todos os casos, os cães afetados demonstraram sinais de síndrome tálamo-cortical, principalmente alteração do nível de consciência, tetraparesia, rigidez extensora e crise convulsiva. Em alguns casos, os cães acometidos apresentaram sinais de síndrome cerebelar, como tremores musculares generalizados de alta frequência e baixa amplitude, e/ou de síndrome vestibular, como ataxia, inclinação de cabeça e quedas. Esses sinais ocorreram entre 24 e 48 horas após o uso do fármaco injetável por via intramuscular e se mantiveram até a morte ou eutanásia dos cães (entre 1 e 7 dias). Tais sinais clínicos refletiam encefalomalacia hemorrágica focal simétrica, que afetava a medula oblonga, a ponte, a medular do cerebelo, o tálamo, o mesencéfalo, os pedúnculos cerebelares e os núcleos da base. Esse artigo: 1) descreve e discute essa forma de intoxicação medicamentosa tão pouco citada na literatura internacional e desconhecida da maior parte dos clínicos e patologistas veterinários brasileiros, 2) estabelece critérios clínicos e anatomopatológicos para o seu diagnóstico e, principalmente, 3) atenta para os riscos da utilização desse princípio ativo na terapêutica canina.

The epidemiological, clinical, and pathological aspects of diminazene aceturate (DA) spontaneous toxicosis were evaluated in 10 dogs. All affected dogs developed signs of thalamic-cortical syndrome, characterized mainly by neurological changes in the conscience levels, tetraparesis, extensor stiffness, and seizures. In some cases there was also evidence of cerebellar syndrome, characterized by generalized muscle tremors (high-frequency and low-amplitude) and/or vestibular syndrome, characterized by or ataxia, head tilt, and falling. These clinical signs occurred between 24 and 48 hours following intramuscular administration of DA and persisted until spontaneous death or euthanasia occurred between 1 and 7 days after the onset of clinical signs. The mentioned clinical signs reflected lesions that consisted of focal symmetrical hemorrhagic encephalomalacia affecting medulla oblongata, pons, cerebellar medulla, thalamus, midbrain, cerebellar peduncles, and basal nuclei. This article (1) describes and discusses DA toxicosis in dogs, a poorly-described clinical entity that is unknown by most clinicians and pathologists in Brazil; (2) establishes the clinical and pathological criteria for the diagnosis of DA toxicosis in dogs; and (3) calls up the attention for the risks of using DA in dogs in clinical settings.

Influence of infection by Toxoplasma gondii on purine levels and E-ADA activity in the brain of mice experimentally infected mice.

The aim of this study was to assess the purine levels and E-ADA activity in the brain of mice (BALB/c) experimentally infected with Toxoplasma gondii. In experiment I (n=24) the mice were infected with RH strain of T. gondii, while in experiment II (n=36) they were infected with strain ME-49 of T. gondii. Our results showed that, for RH strain (acute phase), an increase in both periods in the levels of ATP, ADP, AMP, adenosine, hypoxanthine, xanthine (only on day 6 PI) and uric acid (only on day 6 PI). By the other hand, the RH strain led, on days 4 and 6 PI, to a reduction in the concentration of inosine. ME-49, a cystogenic strain, showed some differences in acute and chronic phase, since on day 6 PI the levels of ATP and ADP were increased, while on day 30 these same nucleotides were reduced. On day 60 PI, ME-49 induced a reduction in the levels of ATP, ADP, AMP, adenosine, inosine and xanthine, while uric acid was increased. A decrease of E-ADA activity was observed in brain on days 4 and 6 PI (RH), and 30 PI (ME-49); however on day 60 PI E-ADA activity was increased for infection by ME-49 strain. Therefore, it was possible to conclude that infection with T. gondii changes the purine levels and the activity of E-ADA in brain, which may be associated with neurological signs commonly observed in this disease.

Changes in purine levels associated with cellular brain injury in gerbils experimentally infected with Neospora caninum.

The present study was carried out in order to assess the possible alterations in purine levels of brain, associated neuronal lesions in gerbils experimentally infected with Neospora caninum. For that, gerbils (Meriones unguiculatus) were inoculated with Nc-1 strain of N. caninum, composing two different experiments: Experiment I (EI) and experiment II (EII), where purine levels were measured along with the histopathologic study, on days 7 (EI), 15 and 30 (EII), post-infection (PI). As a result, it was possible to observe that the purine levels (ATP, ADP, AMP, adenosine, inosine and xanthine) in brain in EI are significantly reduced (p < 0.05), while in EII we faced a different pattern, since in the majority the purine levels were significantly increased (p < 0.05) on days 15 (ATP, AMP, adenosine, hypoxanthine and xanthine) and 30 PI (ATP, ADP, AMP, adenosine, and uric acid). Results of brain histopathology did not show histological lesion in animals of EI; however, in gerbils of EII it was possible to verify that the alterations (lesions) were more pronounced in gerbils evaluated on day 30 PI when compared to day 15 PI. Therefore, it was possible to conclude that the purine levels in brain were altered in both experiments, concomitant with the histopathological injuries observed in EII.

Neospora caninum and Toxoplasma gondii: relationship between hepatic lesions, cytological and biochemical analysis of the cavitary liquid during the acute phase of the diseases in experimental models.

The objective of this study was to evaluate the pathogenesis of ascites in mice infected with Toxoplasma gondii and gerbils infected with Neospora caninum during the acute phase disease. For that, 12 gerbils [Experiment I: not infected/control (n=6) and infected (n=6)] and 12 mice [Experiment II: control (n=6) and infected (n=6)] were used. Infected gerbils and mice showed marked ascites on days 5-7 post-infection (PI), while the not-infected animals had not ascites. Peritoneal liquid was collected from the all mice with uninfected animals receiving 1.5mL of saline solution into their abdominal cavity, allowing the recovery of cavity liquid. As a result, it was possible to observe differences in physics, chemistry and cytological analysis of the fluid cavity of animals infected with N. caninum and T. gondii, when they were compared with uninfected animals, as well as between animals experimentally infected. Additionally both, N. caninum and T gondii, caused an increase in the levels of nitric oxide (NOx-nitrate/nitrite), protein oxidation (AOPP) and lipid peroxidation (TBARS), while serum total protein and albumin were reduced in infected gerbils and mice. Gerbils infected with N. caninum showed multiple large cells with multilobulated nucleus, lytic necrosis and abundant amount of eosinophilic cytoplasm into the hepatic parenchyma. By the other hand, mice infected with T. gondii developed myriad foci of lytic necrosis combined with tachyzoites and cysts containing bradyzoites in liver. Both experimental models for N. caninum and T. gondii showed inflammatory foci and tachyzoites the peritoneum, which could be a major cause of ascites. Toxoplasmosis and neosporosis were able to cause clinical signs in experimental models with similar alterations in peritoneal fluid; however the toxoplasmosis histological changes were much more evident. Therefore, the pathogenesis of ascites appears to be directly related to liver damage, which strongly suggests alteration in the normal production of proteins as observed in this study, along with peritonitis.

Prevalência e achados epidemiológicos, anatomopatológicos e imuno-histoquímicos dos tumores hepáticos malignos primários de cães da Região Central do Rio Grande do Sul (1965-2012) / Prevalence and epidemiological, pathological and immunohistochemical aspects of primary canine malignant hepatic tumors in Rio Grande do Sul, Brazil (1965-2012)

A prevalência e os aspectos epidemiológicos, anatomopatológicos e imuno-histoquímicos dos tumores hepáticos malignos primários (THMP) em cães foram estudados. De 7.373 cães necropsiados em 48 anos (1965-2012), 64 morreram de THMP, o que corresponde a 0,9% do total de cães que morreram por qualquer causa, 7,8% do total de cães que morreram por tumores em geral e 33,5% do total de cães que morreram por tumores hepáticos. Desses 64 casos de THMP, 51 foram revistos histologicamente, avaliados imuno-histoquimicamente e reclassificados como carcinomas (colangiocarcinomas [n=36], carcinomas hepatocelulares [n=9] e hepatocolangiocarcinoma [n=1]) e sarcomas (hemangiossarcomas [n=5]). Dos cães com colangiocarcinomas e carcinomas hepatocelulares em que a idade estava disponível nos protocolos, 64,7% e 77,8% eram idosos, respectivamente. Na necropsia, colangiocarcinomas caracterizaram-se principalmente por ocorrerem em um padrão multinodular (83,3%), enquanto carcinomas hepatocelulares ocorreram tanto de forma massiva (44,4%) quanto nodular (44,4%). Metástases extra-hepáticas foram vistas em 77,8% e 33,3% dos casos de colangiocarcinomas e carcinomas hepatocelulares, respectivamente, e em relação aos colangiocarcinomas afetaram principalmente pulmões (52,8%), linfonodos (50%) e peritônio (19,4%). Ascite (22,2%) e icterícia (22,2%) foram achados associados ocasionalmente com ambos os tumores. Na histologia, a maior parte dos colangiocarcinomas (86,1%) e dos carcinomas hepatocelulares (55,6%) tinha padrão tubular e trabecular, respectivamente. Na imuno-histoquímica, a maioria (63,9%) dos colangiocarcinomas demonstrou imunomarcação para CK7 e nenhum imunomarcou para Hep Par 1. A maioria (55,6%) dos carcinomas hepatocelulares demonstrou imunomarcação para Hep Par 1 e nenhum imunomarcou para CK7. Os resultados aqui apresentados demonstram uma altíssima prevalência de THMP, principalmente colangiocarcinomas, e servem para auxiliar, através dos achados de necropsia, histologia e imuno-histoquímica, patologistas veterinários no diagnóstico dessa tão comum forma de câncer em cães da Região Central do RS, Brasil.

The prevalence and epidemiological and immunohistochemical aspects of primary hepatic malignant tumors (PHMT) were reviewed in dogs necropsied in a 48-year period (1965-2012). Out of those7,373 dogs, 64 died due to PHMT, which corresponds to 0.9% of the dogs dying from any cause in the period; 7.8% of dogs which deaths were caused by tumors in general; and 33.5% of all dogs dying from hepatic tumors (primary and metastatic). Out of the 64 cases of PHMT, 51 were reviewed histologically and evaluated by immunohistochemistry; they were diagnosed as carcinomas (36 cholangiocarcinomas, 9 hepatocellular carcinomas and one hepatocholangiocarcinoma) and sarcomas (5 hemangiosarcomas). In those dogs in which the age was possible determined, 64.7% (cholangiocarcinomas) and 77.8% (hepatocellular carcinomas) were old. At necropsy examination cholangiocarcinomas were characterized mainly by a multinodular pattern (83.3%) while hepatocellular carcinomas occurred both as massive (44.4%) or nodular (44.4%) distribution. Extra-hepatic metastasis occurred respectively in 77.8% and 33.3% of the cases of cholangiocarcinomas and hepatocellular carcinomas; metastatic cholangiocarcinomas affected mainly the lungs (52.8%), lymph nodes (50%) and peritoneum (19.4%). Ascites (22.2%) and icterus (22.2%) were observed frequently associated to both tumors. Histologically, most part of the cholangiocarcinomas (86.1%) and of the hepatocellular carcinomas (55.6%) presented respectively a tubular or trabecular type. Immunohistochemistry revealed that the majority (63.9%) of cholangiocarcinomas was positive for CK7 and none was marked for Hep Par 1. The majority (55.6%) of the hepatocellular carcinomas revealed positive reaction for Hep Par 1 and none was marked for CK7. The results presented here demonstrated a very high prevalence of PHMT, especially cholangiocarcinomas, in the dog. The necropsy, histological and immunohistochemical findings reported might be useful to help veterinary pathologists in the diagnosis of this common form of cancer in dogs of the Rio Grande do Sul, Brazil.

Relationship between butyrylcholinesterase activity and liver injury in mice acute infected with Toxoplasma gondii.

This study aimed to investigate the butyrylcholinesterase (BChE) activity in mice experimentally infected with Toxoplasma gondii during the acute phase. Twenty mice were divided in two groups with 10 animals each: group A was composed of uninfected mice while group B was formed by rodents infected with T. gondii. Five days after infection, blood was collected and serum separated, and fragments of liver and brain were obtained. In serum and liver homogenate was noted a significant reduction (P<0.05) in BChE activity in infected mice when compared with uninfected ones. In serum was observed an increase in the activity of alanine aminotransferase and urea, associated with reduction in alkaline phosphatase activity and in the levels of total protein and albumin. Histologically, there were foci of necrosis and parasites in the forms of tachyzoites and cysts, with bradyzoites in liver samples of infected animals. Based on these results, we conclude that toxoplasmosis reduces BChE activity in mice, and this alteration is probably related to the liver damage caused by the parasitism. Therefore, this enzymatic alteration can directly contribute to the pathogenesis of the disease.