Enteric associated T-cell lymphoma in a mule.

A 25-year-old female mule weighing 336 kg was referred with a history of lethargy, abdominal discomfort, anorexia, and constipation in the previous 24 hours. On admission, decreased intestinal borborygmi and distended small intestinal loops were detected by auscultation and rectal palpation, respectively. On rectal examination a firm, irregular surface, and pedunculated mass were detected in the middle-caudal region of the abdomen. Transrectal ultrasonography revealed the mass was highly vascularized with heterogeneous tissue density. On exploratory celiotomy two neoplastic masses were observed, one in the jejunoileal junction obstructing the intestinal flow and the second in the dorsal part of the jejunal mesentery, unable to be exposed and resected. An enterectomy was conducted, and the intestinal mass was removed. The mass was pale with hemorrhagic areas and 12 cm in diameter. Histopathology and immunohistochemistry confirmed a diagnosis of enteric associated T cell lymphoma subtype 2. The mule died suddenly 43 days later.

Pathology in Practice.

In collaboration with the American College of Veterinary Pathologists.

Potential effect of hyaluronic acid and triamcinolone acetate, alone or combined, on chondrogenic differentiation of mesenchymal stem cells / Efecto potencial del ácido hialurónico y del acetato de triamcinolona solos o combinados sobre la diferenciación condrogénica de células-tronco mesenquimales / Efeito potencial do ácido hialurônico e triancinolona acetonida, isolados e combinados, na diferenciação condrogênica de células-tronco mensenquimais

Abstract Background: Osteoarthritis is a complex degenerative disease with several factors contributing to joint damage. Objective: To compare the potential effect of hyaluronic acid (HA) and triamcinolone acetonide (TA), alone or combined, on the in vitro chondrogenic differentiation process of mesenchymal stem cells (MSCs). Methods: MSCs were divided into four groups: Control, HA, TA, and HA/TA combined. Each treatment group was cultured for 14 days in chondrogenic differentiation medium. The chondrogenic differentiation potential was assessed by histology and immunohistochemistry. Results: The HA and HA/TA-treated MSCs presented histological characteristics similar to native chondrocytes. The extracellular matrix (ECM) of TA-treated MSCs was compact and organized. Glycosaminoglycan staining was intense in Control, moderate in TA, slight in HA/TA, and undetectable in HA. Type II collagen immunoreactivity was high in the TA-treated ECM and MSCs. Conclusions: Histological analysis shows that HA influences morphological development similar to chondrocytes of the MSCs, but with low expression of specific cartilage molecules. The TA promotes formation of a compact and organized ECM.

Resumen Antecedentes: La osteoartritis es una enfermedad degenerativa compleja en la cual varios factores contribuyen al daño articular. Objetivo: Comparar el efecto del ácido hialurónico (HA) y acetónido de triamcinolona (TA), solos o en combinación, en el proceso de diferenciación condrogénica in vitro de células madre mesenquimales (MSCs). Métodos: Las MSCs fueron divididas en cuatro grupos: Control, HA, TA y HA/TA, y cultivadas por 14 días en medio de diferenciación condrogénica para cada tratamiento. El potencial de diferenciación condrogénica fue analizado por medio de histología e inmunohistoquímica. Resultados: Las MSCs tratadas con HA y HA/TA, presentaron características histológicas similares a los condrocitos nativos, y la matriz extracelular (ECM) de MSCs tratadas con TA fue más compacta y organizada. La tinción de glicosaminoglicanos fue intensa en el Control, moderada en TA, ligera en HA/TA, y sin tinción en HA. La inmunoreactividad para colágeno tipo II fue más alta en las MSCs y ECM tratadas con TA. Conclusión: El análisis histológico muestra que el HA influencia un desarrollo morfológico similar a los condrocitos de las MSCs, pero con baja expresión de moléculas específicas de cartílago. La TA promueve la formación de una ECM compacta y organizada.

Resumo Antecedentes: A osteoartrite é uma doença degenerativa complexa, na qual vários fatores contribuem ao dano articular. Objetivo: Comparar o efeito do ácido hialurônico (HA) e Triancinolona acetonida (TA), só ou combinado no processo de diferenciação condrogênica in vitro de células tronco mesenquimais (MSCs). Métodos: MSCs foram divididas em 4 grupos: Controle, HA, TA y HA/TA e cultivadas por 14 dias com meio de diferenciação condrogênica e seus respectivos tratamentos. O potencial de diferenciação condrogênica foi acessado por meio de histologia e imunohistoquímica. Resultados: Histologicamente, MSCs tratadas com HA e HA/TA apresentaram características semelhantes de condrócitos nativos, e a matriz extracelular de MSCs tratadas com TA foi mais compacta e organizada. A coloração para glicosaminoglicanos foi intensa no Controle, moderada no TA, leve no HA/TA e sem coloração com HA. Para os grupos tratamento, a imunoreatividade para colágeno tipo II foi maior nas células e matriz extracelular tratadas com TA. Conclusão: Mediante análise histológica, o HA influenciou o desenvolvimento morfológico semelhante a condrócitos das MSCs, mas com baixa expressão de moléculas específicas de cartilagem. A TA promoveu a formação de uma matriz extracelular compacta e organizada.

Post-mortem CT vs necropsy in feline medicine.

OBJECTIVES: The aim of this study was to compare post-mortem CT findings with necropsy findings in domestic cats. METHODS: Post-mortem CT and necropsies were performed in 20 cadavers of domestic cats. The sensitivity, specificity and agreement between the post-mortem CT and necropsy findings were determined. RESULTS: There were a total of 315 post-mortem findings; 183 were identified by post-mortem CT and 132 were identified by necropsy. Post-mortem CT demonstrated a higher sensitivity to identify the findings mainly in bones. The higher indices of agreement between post-mortem CT and necropsy were related to abnormalities of pleural space, bones and joints. CONCLUSIONS AND RELEVANCE: This study demonstrated that post-mortem CT and necropsy provided different information. Thus, their use in conjunction with each other might improve the understanding of the cause of death and the identification of post-mortem lesions.

Osteopontin expression and its relationship with prognostic biomarkers in canine mammary carcinomas / Expressão de osteopontina e sua relação com biomarcadores prognóstico nos carcinomas mamários caninos

Osteopontin is a glycophosphoprotein implicated in different physiologic and pathologic processes and is known to be involved in progression and metastasis of various cancers in humans, but this relation is still little explored in the veterinary. The aim was to evaluate the expression of osteopontin in canine mammary carcinomas and its relation with well-established canine mammary tumor biomarkers. For that, expression of OPN, EGFR, HER2, and c-Kit were evaluated along with Ki67 rate in 43 mammary carcinomas. Osteopontin was demonstrated to be expressed by neoplastic epithelial cells in all carcinomas as well as in stromal cells from the tumor microenvironment. Relation between high osteopontin expression and EGFR positivity (P<0.001) and HER2 overexpression (P=0.012) was demonstrated. In conclusion, high OPN expression seems to be related to poor prognosis and MAPK pathway activation, given the association with EGFR and HER2, members of the MAPK signaling pathway.(AU)

A osteopontina é uma glicofosfoproteina implicada em diferentes processos fisiológicos e patológicos, sendo conhecida por estar envolvida na progressão e metástase de vários cânceres nos humanos, no entanto, essa relação é ainda pouco explorada na veterinária. O objetivo deste trabalho foi avaliar a expressão da osteopontina nos carcinomas mamários caninos e sua relação com biomarcadores bem estabelecidos para esta neoplasia. Para isto, foi avaliada a expressão de OPN, EGRH, HER2 e c-Kit juntamente com a taxa de Ki67 em 43 carcinomas mamários. A osteopontina foi expressa pelas células epiteliais neoplásicas em todos os carcinomas, assim como, nas células estromais do microambiente tumoral. Foi demonstrada uma relação entre uma alta expressão de osteopontina e positividade para EGFR (P<0.001) e superexpressão de HER2 (P=0.012). Em conclusão, alta expressão de OPN parece estar relacionada com mau prognóstico e ativação da via MAPK, devido a sua associação com EGRF e HER2, os quais são membros desta via de sinalização.(AU)

The role of the multi-drug resistance 1, p53, b cell lymphoma 2, and bcl 2-associated X genes in the biologic behavior and chemotherapeutic resistance of canine transmissible venereal tumors.

BACKGROUND: Canine transmissible venereal tumors (CTVTs) generally have different cytomorphologic subtypes and phases of progression. Some tumors have variable biologic behavior including a progressive increase in tumor aggressiveness and variable responses to chemotherapy. This behavior is partially due to high p-glycoprotein expression by tumor cells, which leads to the expulsion of chemotherapeutic drugs. Other possible causes include changes in pro- and anti-apoptotic genes from the BCL-2 family and DNA repair systems, which are associated with the p53 gene family. OBJECTIVES: We aimed to determine the relative expression of the multi-drug resistance 1 (MDR1), p53, b-cell lymphoma 2 (BCL2), and bcl 2-associated X (BAX) genes in CTVT before and after therapy and establish a relationship with treatment responses, cytomorphologic patterns, and tumor progression identified with histopathology. METHODS: RT-qPCR was performed on 21 CTVT tumor samples before and after initiating chemotherapy to determine specific gene expression. Normal canine testicular tissue was used as a negative control for all experiments. RESULTS: MDR1 expression was decreased before and after initiating vincristine therapy in CTVT tumor tissues compared with normal canine testicular tissue; p53 and BAX were overexpressed at both time points compared with normal tissue, and no statistical differences were seen between the different morphologic types. However, BAX expression was decreased in the group with quick therapeutic responses but was still overexpressed compared with normal testicular tissue. In the group with the slowest chemotherapeutic responses, BCL2 was overexpressed. CONCLUSION: The findings of this study showed a relative increase in MDR1 gene expression in response to chemotherapy and higher expression in plasmacytoid CTVTs compared with the other cytomorphologic patterns. BCL2 overexpression was related to a favorable prognosis, and p53, BAX, and BCL2 were expressed independent of the cytomorphologic CTVT type. All of the genes were expressed independent of tumor progression, as noted on histopathology.

Sonography and sonoelastography in the detection of malignancy in superficial lymph nodes of dogs.

BACKGROUND: The clinical applicability of sonography and sonoelastography (SOE) in the detection of lymph node malignancy in dogs has not been established. OBJECTIVES: To compare sonographic and sonoelastographic findings between malignant and benign superficial lymph nodes and to evaluate the diagnostic performance of those methods. ANIMALS: One-hundred sixteen lymph nodes of 54 dogs. METHODS: A prospective observational study was used to investigate sonographic features and elasticity scores of malignant and benign superficial lymph nodes. Lymph nodes were categorized as malignant or benign according to cytology or histopathology. Quantitative variables were compared using Student's unpaired t test. Prevalence of categorical variables was compared using nonparametric Mann-Whitney U test. Diagnostic performance was calculated by receiver-operating characteristic analysis. RESULTS: Forty-nine malignant and 67 benign lymph nodes were included. Malignant nodes had larger long axis (LA; P = .0002), short axis (SA; P < .0001) and short-to-long axis ratio (P < .0001) in comparison with benign nodes. Malignant nodes had a higher prevalence of mixed vascular distribution on Doppler color flow mapping (P < .005) and on power Doppler (P < .0001) and higher resistivity index (RI; P < .0001), pulsatility index (P < .0001), and elasticity score (P < .0001) in comparison with benign nodes. Short axis, elasticity score, and RI offered the best accuracies, 80.2%, 78.1%, and 77.7% (P < .05), respectively, for malignancy detection. CONCLUSIONS AND CLINICAL IMPORTANCE: Results support the use of Doppler sonography and SOE as auxiliary methods to brightness mode sonography to detect nodal malignancy.

Spontaneous poisoning by Palicourea marcgravii (Rubiaceae) in a sheep herd in southeastern Brazil.

Palicourea marcgravii (Rubiaceae) is considered the most important toxic plant affecting livestock farming in Brazil. This study describes an outbreak of spontaneous poisoning by P. marcgravii in sheep. Forty-nine sheep died while showing clinical signs of sudden death after having access to the plant. During the necropsy, P. marcgravii leaves were observed in the rumens of the animals. Histopathological analysis demonstrated hydropic degeneration of the kidneys. Monofluoracetate concentration obtained in Palicourea samples was 0.53% (5.3 µg/mg). These findings collectively indicate that the affected animals died from poisoning due to P. marcgravii.

Immunocytochemical characterization of primary cell culture in canine transmissible venereal tumor / Caracterização imunocitoquímica de culturas primárias de tumor venéreo transmissível canino

Immunochemistry with anti-vimentin, anti-lysozyme, anti-alpha 1 antitrypsin, anti-CD3 and anti-CD79α antibodies has been used for characterization of primary cell culture in the transmissible venereal tumor (TVT). Samples for primary cell culture and immunohistochemistry assays were taken from eight dogs with cytological and clinical diagnosis of TVT. To validate the immunochemical results in the primary cell culture of TVT, a chromosome count was performed. For the statistical analysis, the Mann-Whitney test with p<0.05 was used. TVT tissues and culture cells showed intense anti-vimentin immunoreactivity, lightly to moderate immunoreactivity for anti-lysozyme, and mild for anti-alpha-antitrypsin. No marking was achieved for CD3 and CD79α. All culture cells showed chromosomes variable number of 56 to 68. This is the first report on the use of immunocytochemical characterization in cell culture of TVT. Significant statistic difference between immunochemistry in tissue and culture cell was not established, what suggests that the use of this technique may provide greater certainty for the confirmation of tumors in the primary culture. This fact is particularly important because in vitro culture of tumor tissues has been increasingly used to provide quick access to drug efficacy and presents relevant information to identify potential response to anticancer medicine; so it is possible to understand the behavior of the tumor.(AU)

Os anticorpos anti-vimentina, anti-lisozima, anti-alfa 1 antitripsina, anti-CD3 e anti-CD79α foram empregados para a caracterização de culturas primárias de tumor venéreo transmissível canino (TVT). Amostras para cultura primária e imuno-histoquímica foram coletadas de oito cães com diagnóstico clínico e citológico de TVT. Para validar o resultado inmunocitoquímico nas culturas de TVT foi realizada a contagem de cromossomos. Para a análise estatística o teste de Mann-Whitney foi empregado a um nível de significância de p<0.05. As culturas e os tecidos de TVT apresentaram intensa reatividade para vimentina, moderada a leve para Lisozima, moderada para alfa-antitripsina e não houve marcação para CD3 e CD79α. Finalmente, todas as culturas apresentaram números de cromossomos que variaram de 56 a 68. Este é o primeiro relato que apresenta o uso da immunocitoquímica para a caracterização de culturas de TVT. Assim, e devido ao fato de se observar semelhança entre a imunomarcação em células e tecidos, sugere-se que o uso desta técnica possa auxiliar na confirmação de culturas primárias do tumor, fato muito importante porque a utilização da cultura do tumor pode permitir o acesso a informação relevante sobre resposta potencial a um tratamento e conhecimento do comportamento biológico do tumor.(AU)

Immunoexpression of S100A4 in canine skin melanomas and correlation with histopathological parameters.

BACKGROUND: Melanoma is one of the most common skin neoplasms in humans and dogs. The tumor microenvironment in melanoma comprises cancer cells and stromal cells that interact to accelerate tumor progression. Several prognostic markers for melanomas have been studied in many human tumors, including fibroblast-specific protein 1 (S100A4). S100A4 is a member of the S100 family of calcium-binding proteins in stromal cells. HYPOTHESIS/OBJECTIVES: The objective of this study was to describe the immunohistochemical patterns of S100A4 in stroma and neoplastic cells of canine skin melanomas and correlate them with some histological parameters. ANIMALS AND METHODS: Forty-eight samples (38 pigmented and 10 non-pigmented melanomas) were first selected and their nature confirmed using S100, Melan A and vimentin. All cases were examined by immunohistochemistry using S100A4 to correlate expression, histotype, and level of invasion. RESULTS: All the tumors, including 10 non-pigmented, were positive for S100, Melan A, vimentin and negative for cytokeratin AE1/AE3 (consistent with melanomas). The 48 melanomas were classified as epithelioid (n = 21), spindle (n = 14), and mixed (n = 13). S100A4 was preferentially expressed in epithelioid and spindle cell types compared with mixed melanomas and S100A4 expression was not associated with level of invasion (Clark's levels IV to V). CONCLUSION: S100A4 expression in melanoma samples varied among histotypes but not between levels of invasion.

Clinical, cytologic, and histologic features of a mammary micropapillary carcinoma in a dog.

Mammary invasive micropapillary carcinoma is a rare variant of mammary carcinoma that was recently recognized in dogs. The cytologic features and biologic behavior of such neoplasms in dogs have not yet been widely discussed in the veterinary literature. We report the clinical, cytologic, and histologic features of a canine micropapillary carcinoma in a 13-year-old female mongrel dog. The mammary region presented with extreme local pain, severe edema and erythema, and multifocal epidermal ulceration, which is typical for an inflammatory mammary carcinoma. Fine-needle aspirates were highly cellular and consisted of individual cells and papillary cell clusters with characteristics of malignant epithelial cells. Histologic examination revealed neoplastic cells arranged in small papillae without fibrovascular cores, sometimes inside clear lymphatic spaces, indicating lymphovascular invasion. Regional lymph node evaluation revealed metastatic cells. Due to deteriorating clinical condition the dog was euthanatized 5 months after mastectomy. At necropsy, metastatic neoplastic mammary cells were found in popliteal and mediastinal lymph nodes, the right femoral biceps muscle, liver, heart, lungs, and urinary bladder.

Grafts of porcine small intestinal submucosa seeded with cultured homologous smooth muscle cells for bladder repair in dogs.

BACKGROUND: Due to numerous complications associated to gastrointestinal augmented cystoplasty, this study aimed to analyze the anatomic repair of the bladder of 10 female dogs using grafts of porcine small intestinal submucosa (SIS) seeded with cultured homologous smooth muscle cells, and compare them with the acellular SIS grafts. RESULTS: We assessed the possible side effects and complications of each type of graft by clinical examination, abdominal ultrasound and laboratory findings. Anatomic repair of neoformed bladder was assessed by histological staining for H/E and Masson's Trichrome, analyzed with a Nikon Photomicroscope connected to the system of image analysis Image J. CONCLUSIONS: We propose that SIS associated to homologous smooth cells can improve the quality of tissue repair, and consequently decrease the potential complications inherent to acellular SIS.

Photodynamic therapy for the treatment of induced mammary tumor in rats.

The objective of this work was to evaluate photodynamic therapy (PDT) by using a hematoporphyrin derivative as a photosensitizer and light-emitting diodes (LEDs) as light source in induced mammary tumors of Sprague-Dawley (SD) rats. Twenty SD rats with mammary tumors induced by DMBA were used. Animals were divided into four groups: control (G1), PDT only (G2), surgical removal of tumor (G3), and submitted to PDT immediately after surgical removal of tumor (G4). Tumors were measured over 6 weeks. Lesions and surgical were LEDs lighted up (200 J/cm(2) dose). The light distribution in vivo study used two additional animals without mammary tumors. In the control group, the average growth of tumor diameter was approximately 0.40 cm/week. While for PDT group, a growth of less than 0.15 cm/week was observed, suggesting significant delay in tumor growth. Therefore, only partial irradiation of the tumors occurred with a reduction in development, but without elimination. Animals in G4 had no tumor recurrence during the 12 weeks, after chemical induction, when compared with G3 animals that showed 60 % recurrence rate after 12 weeks of chemical induction. PDT used in the experimental model of mammary tumor as a single therapy was effective in reducing tumor development, so the surgery associated with PDT is a safe and efficient destruction of residual tumor, preventing recurrence of the tumor.

Exame citológico em medicina veterinária: estudo retrospectivo de 11.468 casos (1994-2008) / Cytological examination in veterinary medicine: Retrospective study of 11.468 cases (1994-2008)

Foi realizado um estudo retrospectivo dos resultados dos exames citológicos provenientes dos arquivos do Serviço de Citopatologia do Laboratório de Patologia Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, Botucatu, São Paulo, entre janeiro de 1994 e dezembro de 2008. Do total de 139.986 animais atendidos no Hospital Veterinário da instituição, 11.468 (8,2%) foram encaminhados para exame citológico. Desses diagnósticos, 57,28% corresponderam a lesões neoplásicas, 19,28% a lesões inflamatórias e 14,79% a processos não neoplásicos (imunológicos, degenerativos, hiperplásicos ou displásicos). Não foi possível concluir o diagnóstico por meio do exame citológico em 7,28% dos casos e não haviam informações diagnósticas registradas em 1,37% dos casos. Dentre os animais que mais receberam indicação para exame citológico destacaram-se os caninos (92,06%), seguidos pelos felinos (4,08%), bovinos (1,77%) e equinos (1,30%). Lesoes neoplásicas foram as mais comumente observadas e foram mais prevalentes nos cães (59,18%), afetando principalmente animais com idade média de 119,60 meses e principalmente fêmeas (61,61%). O incremento anual observado ao longo dos 15 anos de aplicação da citologia demonstra que o exame citológico é um método de suma importância para confirmar, sugerir ou afastar o diagnóstico de diversas afecções, inclusive neoplasia, em todas as espécies animais.

A retrospective study was conducted over the results of cytological examination in the files of the Department of Cytopathology, Laboratory of Animal Pathology, School of Veterinary Medicine and Animal Science, São Paulo State University, Botucatu, SP, Brazil, from January 1994 to December 2008. Out of 139,986 animals referred to the teaching Veterinary Hospital, 11,468 (8.2%) were submitted to cytological examination. From these animals, 57.28% had a neoplastic lesion, 19.28% had inflammatory lesions, and 14.79% had non-neoplastic processes (immune-mediated, degenerative, hyperplastic, or dysplastic condition). By means of cytology, 7.28% of the cases were unable to be diagnosed, and there was no recorded diagnostic information in 1.37% of cases. The species that more commonly had samples submitted to cytology was the dog (92.06%), followed by cats (4.08%), cattle (1.77%), and horses (1.30%). As to the predominance of the observed processes, greater importance was given to neoplastic lesions. These were prevalent in dogs (59.18%), with a mean age of 119.60 months, and affecting mainly females (61.61%). The annual increase observed over the 15 years of application of cytology demonstrates that the cytological examination is a method of great importance to confirm, suggest, or exclude the diagnosis of various diseases, including cancer, in all animal species.

Adenocarcinoma of the parotid salivary gland in a cow.

A 6-year-old Girolando dairy cow was presented for evaluation of a large subcutaneous facial mass. Fine-needle aspirates of the mass contained many neoplastic cells with high nuclear:cytoplasmic ratios arranged in sheets and loosely cohesive clusters with streaming erythrocytes and neutrophils in the background. Neoplastic cells were 13-25 µm in diameter and were round to cuboidal with variably distinct borders. Based on the signalment, anatomic location, and cytologic findings, differential diagnoses included salivary adenocarcinoma, squamous cell carcinoma, and mucoepidermoid carcinoma. The cow was euthanized and a necropsy was performed. The primary neoplasm arose from the left parotid salivary gland and meastatic tumor was found in the regional lymph nodes and lung. Histologically, the tumor was composed of anastomosing and irregular solid islets surrounded by scant stroma. Cells were negative for periodic acid-Schiff (PAS), PAS-diastase, and Alcian blue pH 2.5 stains, used to detect mucin. On immunohistochemical analysis, neoplastic luminal salivary gland cells expressed cytokeratin, but not S100, α-smooth muscle actin, or vimentin. Peripheral cells of neoplastic islets were immunoreactive for p63. The final diagnosis was nonsecretory adenocarcinoma of the parotid salivary gland.

Ocular melanoma and mammary mucinous carcinoma in an African lion.

BACKGROUND: Reports of neoplasms in Panthera species are increasing, but they are still an uncommon cause of disease and death in captive wild felids. The presence of two or more primary tumor in large felids is rarely reported, and there are no documented cases of ocular melanoma and mammary mucinous carcinoma in African lions. CASE PRESENTATION: An ocular melanoma and a mammary mucinous carcinoma are described in an African lion (Panthera leo). The first tumour was histologically characterized by the presence of epithelioid and fusiform melanocytes, while the latter was composed of mucus-producing cells with an epithelial phenotype that contained periodic acid-Schiff (PAS) and Alcian blue staining mucins. Metastases of both tumor were identified in various organs and indirect immunohistochemistry was used to characterize them. Peribiliary cysts were observed in the liver. CONCLUSIONS: This is the first description of these tumor in African lions.

Inhibition of mouse urinary bladder carcinogenesis by açai fruit (Euterpe oleraceae Martius) intake.

Açai, fruit from Euterpe oleraceae Martius, is consumed in natura and in a variety of beverages and food preparations and possesses several potential antioxidant compounds. In a first study for anticarcinogenicity screening, male Swiss mice (n = 20/per group) were chemically-induced to urothelial bladder carcinogenesis for 10 weeks and received a standard diet or a standard diet containing 2.5 and 5 % spray-dried açai pulp (AP) for 10 weeks. At week 20, the incidence of simple and nodular hyperplasia and the incidence and multiplicity of transitional cell carcinoma (TCC) were evaluated. In a second study for antigenotoxicity screening, male Swiss mice (n = 6/per group) were fed standard diet or standard diet containing 5 % AP for three weeks. Urothelial cell suspensions were obtained and challenged with H(2)O(2) for induction of DNA damage and analyzed by comet assay. Overall, dietary 5 % AP reduced TCC incidence and multiplicity (p = 0.019 and p = 0.015, respectively) and tumor cell proliferation and p63 expression (p = 0.02 and p = 0.007, respectively), Furthermore, the group fed the 5 % AP presented a significant reduction (p < 0.01) in DNA damage induced by H(2)O(2), a notable oxidant agent. The results suggest that the spray-dried açai pulp used here inhibits the TCC development in male Swiss mice, probably due to its potential antioxidant action.

Spontaneous canine transmissible venereal tumor: association between different phenotypes and the insertion LINE-1/c-myc / Tumor venéreo transmisible canino espontáneo: asociación entre diferentes fenotipos y la inserción LINE -1/c-myc / Tumor venéreo transmissível canino espontâneo: associação entre diferentes fenótipos e a inserção LINE-1/c-myc

Objective: this study aimed to evaluate the LINE-1 transposon inserted in c-myc gene as a specific genetic alteration in cells of spontaneous canine Transmissible Venereal Tumor (TVT) with either lymphocytoid or plasmacytoid phenotypes. Methods: tumoral biopsies from 35 dogs were collected by puncture or exfoliation. Polymerase Chain Reaction (PCR) was carried out with primers myc.s and LINE. A, specific to the LINE-1 segment to detect the presence of LINE-1/c-myc molecular marker. Results: sequence alignment of DNA samples from lymphocytoid and plasmacytoid TVT cells did not show polymorphisms, and the comparison with sequences from the GenBank identified them as a LINE-1/c-myc rearrangement. Conclusions: considering the aggressive nature of the plasmacytoid phenotype, there is no apparent relation between LINE-1/c-myc and the malignancy of TVT. Further studies are needed to establish molecular differences associated with the aggressiveness of the various phenotypes of canine TVT.

Objetivo: evaluar la expresión del trasposón LINE-1 insertado en el oncogén c-myc como una alteración genética específica en células de Tumor Venéreo Transmisible canino espontáneo con fenotipos linfocitoideos o plasmocitoideos. Métodos: se tomaron muestras citológicas de 35 caninos naturalmente afectados por Tumor Venéreo Transmisible (TVT), separándolas en dos grupos de acuerdo al fenotipo predominante. La identificación del marcador molecular LINE-1/c-myc fue posible mediante la técnica de Reacción en Cadena de la Polimerasa (PCR) usando los primers myc.s y LINE. A, específicos para el segmento LINE-1. Resultados: el resultado del alineamiento de las secuencias obtenidas a partir del DNA de cada uno de los fenotipos de TVT no presentó variación entre ellos y al compararlas con el alineamiento de otras secuencias depositadas en el GenBank, pudo observarse que se trata de un reordenamiento LINE- 1/c-myc. Conclusiones: teniendo en cuenta la naturaleza agresiva del fenotipo plasmocitoide, se estableció que no hay polimorfismo genético entre los grupos analizados, siendo necesario realizar nuevos estudios tendientes a establecer diferencias moleculares asociadas con la agresividad de los diferentes fenotipos del TVT canino.

Objetivo: foi avaliado o elemento de transposição LINE-1 inserido no gene c-myc como alteração genética específica nas células do TVT espontâneo canino nos grupos fenotípicos previamente classificados como linfocitóide e plasmocitóide. Métodos: amostras da lesão de 35 cães foram colhidas por punção ou esfoliação. Para identificar o marcador molecular LINE-1/c-myc nas amostras foi utilizada a técnica de Reação em Cadeia da Polimerase empregando-se os primers myc.s e LINE. A, específicos para o segmento LINE-1. Resultados: o resultado do alinhamento das sequências obtidas das amostras de DNA das células de TVT linfocitóide e plasmocitóide não apresentou polimorfismos e, por meio do alinhamento com outras sequências depositadas no GeneBank, identificou-se que trata-se do rearranjo LINE-1/c-myc. Conclusões: parece não haver relação entre este aspecto molecular analisado com a agressividade do tumor.