Ehlers-Danlos syndrome (cutaneous asthenia) in a Campbell's dwarf hamster (Phodopus campbelli).

A case of cutaneous asthenia in a Campbell's dwarf hamster is described. The animal was found to have hyperextensible skin, glaucoma and lens dislocation. Histopathological examination revealed an irregular, haphazard arrangement of collagen fibres in the dermis. The animal underwent surgical reduction of the skin folds which provided only temporary relief.

Using Super-Resolution for Enhancing Visual Perception and Segmentation Performance in Veterinary Cytology.

The primary objective of this research was to enhance the quality of semantic segmentation in cytology images by incorporating super-resolution (SR) architectures. An additional contribution was the development of a novel dataset aimed at improving imaging quality in the presence of inaccurate focus. Our experimental results demonstrate that the integration of SR techniques into the segmentation pipeline can lead to a significant improvement of up to 25% in the mean average precision (mAP) metric. These findings suggest that leveraging SR architectures holds great promise for advancing the state-of-the-art in cytology image analysis.

Occurrence of mammary gland tumours in male dogs and its weak association with development of testicular tumours: a review.

Mammary gland tumours (MGTs) are commonly occurring neoplasms in female dogs. However, rare cases of MGTs in male dogs have been reported for years. Due to the low incidence of MGTs in male dogs in comparison to female dogs, veterinary oncology is mainly focused on mammary neoplasms diagnosed in female dogs and extensive research is conducted in this scientific area. Therefore, there are no sufficient epidemiological data on male dogs and the aetiology of their tumour development is still poorly understood.The aim of this literature review was to present cases of MGTs in male dogs for better understanding the scale of the problem over the years. The analyses of 74 affected male dogs with 92 tumours showed that the majority of MGTs in male dogs were benign tumours (54.3%), especially in form of adenomas, often developed in posterior canine mammary glands (58.1%).The increased number of canine MGTs in male dogs aged 7 -13 years with an age peak at 11 years was noted. The age of affected animals was not related to breed. Mammary gland neoplasms were diagnosed predominately in Crossbreeds (20.2%) followed by Cocker Spaniels (18.9%) and German Shepherds (10.8%).The association between MGT development in male dogs and co-occurrence of testicular tumours (TTs) has been discussed for years. Thus, cases of development of both tumours were included in this study. As a result, only in 12.7% cases of MGTs also history of TTs was described. Therefore, no general association between these tumours should be assumed.

Immunoreactivity of p21, MMP-1 and CB2 receptor proteins in cutaneous canine mast cell tumours: an association with the three-tier grading system.

Introduction: Mast cell tumours (MCTs) arise in the dermis and subcutaneous tissues in animals and humans and are one of the most common neoplasms of the skin in dogs. Cannabinoid type 2 receptor (CB2R), cyclin-dependent kinase inhibitor (p21) and matrix metalloproteinase 1 (MMP-1) are potential targets for novel anti-tumour therapeutic strategies. This study evaluated by immunohistochemical means the reactivity of p21, MMP-1 and CB2R proteins in association with a three-tier grading system in cutaneous canine MCTs. Material and Methods: Formalin-fixed, paraffin-embedded canine MCTs were processed for histochemical analysis and immunohistochemical staining using antibodies against p21, MMP-1 and CB2R. The results were analysed statistically. Results: The strongest p21 immunolabelling was detected in grade 3 MCTs, while grade 1 tumours showed mild or no detectable p21 immunoreactivity (P-value < 0.001). Strong immunolabelling of MMP-1 was the most common in grade 1 tumours (P-value < 0.001) and CB2R was significantly less frequent in grade 3 tumours than in grade 1 (P-value < 0.001) and grade 2 (P-value < 0.001). Conclusion: High immunoreactivity of MMP-1 can be a marker of grade 1 MCTs in dogs, whereas p21 protein overexpression can be a marker of grade 3 canine MCTs. Strong CB2R immunoreactivity with simultaneous underexpression of p21 and high immunoreactivity of MMP-1 proteins may indicate that the use of cannabinoids in grade 1 MCTs in dogs is practicable.

Incidence and the risk of occurrence of benign and malignant canine skin tumours in Poland - a five-year retrospective study.

Introduction: The aim of the study was to compile data on the frequency and distribution of canine skin tumours and determine the risk of these being malignant as opposed to benign. This determination proceeded from tumour histogenesis and gave consideration to the dog's breed, sex, age and the anatomical location of tumours. Material and Methods: This retrospective five-year epidemiological study included 3,139 canine skin tumours collected in Poland. A univariable logistic regression analysis was performed to determine the odds ratios (ORs) with 95% confidence intervals (CIs). Results: Microscopic analysis showed a significant predominance of benign tumours (65.02%) as well as mesenchymal and melanocytic tumours (59.57%). The most frequently diagnosed were mast cell tumours, accounting for 13.79% of all skin tumours, and other common tumour types were lipomas (6.40%), haemangiopericytomas (5.96%) and malignant melanomas (4.65%). The risk of malignant versus benign tumours was 1.212 times higher in the female than in the male dogs. A higher risk of development of malignant epithelial tumours was found in boxers (OR 4.091), German shepherds (OR 4.085) and flat-coated retrievers (OR 43.596). A higher risk of development of malignant mesenchymal tumours was found in golden retrievers (OR 4.693), boxers (OR 2.342), bulldogs (OR 3.469) and Maltese (OR 2.757). Conclusion: The results may serve as a reference point for further studies of the complex biology of canine skin tumours.

Topoisomerase IIα immunoexpression in feline mammary carcinomas: A correlation with Ki67 immunoexpression and the mitotic count.

The aim of the study was to compare the immunohistochemical expression of topoisomerase IIα protein (Topo IIα) with Ki67 expression and mitotic count in feline mammary carcinomas (FMCs). Topo IIα is considered as a proliferation indicator as well as a molecular target of anthracycline chemotherapy. The studied material included 70 FMCs from female cats treated with mastectomy. Primary mouse monoclonal antibodies directed against Topo IIα and Ki67 were used in immunohistochemical reactions. The number of mitotic figures was counted at 400× magnification in a field of 2.37 mm2. Immunohistochemical reaction for Topo IIα occurred in cell nuclei. The Topo IIα index ranged from 6.12% to 54.60% and was positively correlated with the values of the Ki67 index (r = 0.7193) and the mitotic count (r = 0. 2858). This indicates the potential possibility of use of the immunohistochemical expression of Topo IIα to assess the rate of proliferation in FMCs. The wide range of expression of Topo IIα in individual tumorus found in the conducted studies allows us to hypothesize that its assessment could be used as a predictive marker in chemotherapy of FMCs with the use of anthracyclines. However, this requires confirmation in clinical trials.

The use of optical coherence tomography for skin evaluation in healthy rats.

BACKGROUND: Noninvasive diagnostic techniques allow for morphological and morphometric in vivo evaluation of the skin. Optical coherence tomography (OCT) is a method that allows visualization of dermal structures up to several 100 µm with a resolution of 3-7.5 µm. OBJECTIVES: The aim of the study was the morphological and morphometric assessment of rats' skin using SD-OCT. ANIMALS: Fifteen male Wistar rats, aged 3 and 8 months, weighing 350-450 g. MATERIALS AND METHODS: The skin of the plantar metatarsal area of the right pelvic limb was assessed. The measurements were performed using Spectral Domain Optical Coherence Tomography (SD-OCT) scans and histological images. RESULTS: Spectral Domain Optical Coherence Tomography could determine the boundary between the epidermis and the dermis. Apart from the stratum corneum (SC), it did not allow for the differentiation of the individual epidermal layers. In the SD-OCT and in the histological examination, the mean thicknesses of the layers (µm ± SD) were (respectively): SC 33.053 ± µm(SD 5.85, 29.675 ± 5.54; epidermis 88.2 ± 7.97, 65.126 ± 13.23; dermis 259.86 ± 18.29, 166.05 ± 31.88 µm. There was a correlation between the total epidermal SD-OCT and histological measurements (r = 0.43, p = 0.05). Bland-Altman plots revealed a bias of -19.18 (95% confidence interval) -39.21 to 0.84 µm) in the case of live epidermis (stratum granulosum, stratum spinous, stratum basale). CONCLUSIONS AND CLINICAL RELEVANCE: Spectral Domain Optical Coherence Tomography can be used to evaluate rat epidermis and dermis. The method enables the differentiation of the SC, as well as the epidermis and the dermis. SD-OCT and histological thickness dimensions of the epidermis and skin differ.

Contexte - Les techniques de diagnostic non invasives permettent une évaluation morphologique et morphométrique in vivo de la peau. La tomographie par cohérence optique (OCT) est une méthode qui permet de visualiser les structures dermiques jusqu'à plusieurs centaines de micromètres avec une résolution de 3 à 7,5 µm. Objectifs - Le but de l'étude était l'évaluation morphologique et morphométrique de la peau des rats par SD-OCT. Animaux - Quinze rats Wistar mâles, âgés de 3 et 8 mois, pesant 350-450 g. Matériels et méthodes - La peau de la zone métatarsienne plantaire du membre pelvien droit a été évaluée. Les mesures ont été réalisées à l'aide de scaners SD-OCT (Spectral Domain Optical Coherence Tomography) et d'images histologiques Résultats - Le SD-OCT a pu déterminer la frontière entre l'épiderme et le derme. En dehors de la couche cornée (SC), il n'a pas permis la différenciation des couches épidermiques individuelles. Au SD-OCT et à l'examen histologique, les épaisseurs moyennes des couches (µm ± SD) étaient (respectivement) : SC 33,053 ± µm (SD 5,85, 29,675 ± 5,54 ; épiderme 88,2 ± 7,97, 65,126 ± 13,23 ; derme 259,86 ± 18,29, 166,05 ± 31,88 µm). Il y avait une corrélation entre le SD-OCT épidermique total et les mesures histologiques (r = 0,43, P = 0,05) Les tracés de Bland-Altman ont révélé un biais de -19,18 (intervalle de confiance à 95 %) -39,21 à 0,84 µm) dans le cas d'épiderme vivant (stratum granulosum, stratum spinous, stratum basale). Conclusions et pertinence clinique - Le SD-OCT peut être utilisé pour évaluer l'épiderme et le derme de rat. La méthode permet de différencier le SC, ainsi que l'épiderme et le derme. Le SD-OCT et les dimensions d'épaisseur histologiques de l'épiderme et de la peau diffèrent.

Introducción - las técnicas de diagnóstico no invasivas permiten la evaluación morfológica y morfométrica in vivo de la piel. La tomografía de coherencia óptica (OCT) es un método que permite la visualización de estructuras dérmicas de hasta varios cientos de micrómetros con una resolución de 3 a 7,5 µm. Objetivos - El objetivo del estudio fue la evaluación morfológica y morfométrica de la piel de ratas mediante SD-OCT. Animales - Quince ratas Wistar macho, de 3 y 8 meses de edad, con un peso de 350 a 450 g. Materiales y métodos - Se evaluó la piel de la zona metatarsiana plantar del miembro pélvico derecho. Las mediciones se realizaron utilizando escaneos SD-OCT (Tomografía de Coherencia Óptica de Dominio Espectral) e imágenes histológicas. Resultados - SD-OCT pudo determinar el límite entre la epidermis y la dermis. Aparte del estrato córneo (SC), no permitía la diferenciación de las capas epidérmicas individuales. En la SD-OCT y en el examen histológico, los espesores medios de las capas (µm ± SD) fueron (respectivamente): SC 33.053 ± µm (SD 5.85, 29.675 ± 5.54; epidermis 88.2 ± 7.97, 65.126 ± 13.23; dermis 259.86 ± 18,29, 166,05 ± 31,88 µm. Hubo una correlación entre el SD-OCT epidérmico total y las mediciones histológicas (r = 0,43, P = 0,05). Las gráficas de Bland-Altman revelaron un sesgo de -19,18 (intervalo de confianza del 95 %) -39,21 a 0,84 µm) en el caso de epidermis viva (estrato granuloso, estrato espinoso, estrato basal). Conclusiones y relevancia clínica- SD-OCT se puede utilizar para evaluar la epidermis y la dermis de rata. El método permite diferenciar el SC, así como la epidermis y la dermis. Las dimensiones de grosor de la epidermis y la piel difieren entre SD-OCT y la histología.

Contexto - Técnicas diagnósticas não invasivas permitem a avaliação morfológica e morfométrica in vivo da pele. A tomografia de coerência óptica (OCT) é um método que possibilita a visualização de estruturas dérmicas de até centenas de micrômetros com uma resolução de 3-7,5 µm. Objetivos - O objetivo do estudo foi a avaliação morfométrica e morfológica da pele de ratos utilizando SD-OCT. Animais - Quinze ratos Wistar machos, de três a oito meses de idade, pesando de 350 a 450 g. Materiais e métodos - A pele da região metatársica plantar do membro pélvico direito foi avaliada. As mensurações foram realizadas utilizando o SD-OCT (Spectral Domain Optical Coherence Tomography) e imagens histológicas. Resultados - A SD-OCT foi capaz de determinar o limite entre derme e epiderme. A exceção do estrato córneo (SC), não foi possível a diferenciação das camadas da epiderme individualmente. Na SD-OCT e na avaliação histológica, as espessuras médias das camadas fora, (µm ± DP), respectivamente: SC 33,053 ± 5,85; 29,675 ± 5,54; epiderme 88,2 ± 7,97; 65,126 ± 13,23; derme 259,86 ± 18,29; 166,05 ± 31,88 µm. Houve correlação entre SD-OCT e avaliação histológica nas mensurações da epiderme total (r = 0,43, P = 0,05). Os gráficos de Bland-Altman revelaram um viés de -19,8% (95% de intervalo de confiança) - 39,21 a 0,84 µm) no caso da epiderme viva (estrato espinhoso, estrato granuloso e estrato basal). Conclusões e relevância clínica - SD-OCT pode ser utilizada para avaliar a derme e a epiderme de ratos. Este método permite a diferenciação do SC, bem como da derme e epiderme. Pode haver discrepância na espessura da epiderme e da pele na SD-OCT e análise histológica.

Comparative Expression Analysis of Innate Immune Markers and Phagocytic Activity in Peripheral Blood of Dogs with Mammary Tumors.

Canine innate immune system role in cancer prevention and progression remains poorly understood. It has been revealed that innate immune cells could play a dual role in cancer immunology promoting or inhibiting tumor development and growth. Current immunotherapies target mainly the adaptive anti-tumor response and that may be a reason why they remain ineffective in a majority of patients. It is important to acquire detailed knowledge about innate immune mechanisms to broaden the diagnostic and therapeutic options and employ innate immune cells in anti-cancer therapies. In the present study, 21 female dogs of different breeds and types of spontaneous mammary tumors were investigated. The study aimed to find simple and cheap markers that can be used for preliminary diagnosis, prior to the surgical resection of the tumor. The differences in innate immune cell quantity and function were investigated between female dogs with malignant mammary tumors of epithelial and mesenchymal origin. Flow cytometry was used to evaluate the percentages of CD5+ lymphocytes including CD5low lymphocytes, CD11b integrin expression on leukocytes, phagocytosis, and oxidative burst. The number of CD11b lymphocytes was increased in tumors with epithelial origin compared to the control group. No significant differences were found between the percentages of phagocytic cells neither for granulocytes nor for monocytes. However, the phagocytes of canine patients with tumors of epithelial origin showed increased phagocytosis compared to the control group. The percentages of granulocytes that produced reactive oxygen species (ROS) in response to E.coli and PMA were not altered in patients with malignant tumors compared to control. A statistically significant difference between the number of ROS produced by the single granulocyte was demonstrated only between the group of bitches with epithelial tumors and the control group in case of E. coli stimulation. The obtained results suggest that some innate immune cells may be involved in anti-tumor immune mechanisms and have the potential to be supportive diagnostic markers in canine mammary tumors.

Non-thymoma-associated exfoliative dermatitis in a European shorthair cat: A case report.

The current case report presents a case of non-thymoma-associated exfoliative dermatitis in an 8-year-old European Shorthair female cat. The animal displayed extensive alopecia and excessive peeling of the epidermis. There were no other apparent disorders, except for the skin lesions. Roentgenographic and sonographic examinations, complete blood count and blood serum chemistry analyses, and skin biopsy were performed. The histopathological investigation revealed hyperkeratosis of the epidermis and the infiltration of lymphocytes and macrophages at the dermal-epidermal junction around the hair follicles and sebaceous glands. Moreover, edema of the basal layer and melanin migration from the epidermis to the dermis were observed. The patient underwent treatment with immunosuppressive doses of prednisolone, antibiotic therapy, and baths in anti-seborrheic shampoos and displayed resolution. However, recurrence was observed after one month. Consequently, the patient received cyclosporine A, in addition to the aforementioned treatment and the lesions resolved without relapse.

Effect of Chronic Administration of 5-(3-chlorophenyl)-4-Hexyl-2,4 -Dihydro-3H-1,2,4-Triazole-3-Thione (TP-315)-A New Anticonvulsant Drug Candidate-On Living Organisms.

About 70 million people suffer from epilepsy-a chronic neurodegenerative disease. In most cases, the cause of the disease is unknown, but epilepsy can also develop as the result of a stroke, trauma to the brain, or the use of psychotropic substances. The treatment of epilepsy is mainly based on the administration of anticonvulsants, which the patient must most often use throughout their life. Despite significant progress in research on antiepileptic drugs, about 30% of patients still have drug-resistant epilepsy, which is insensitive to pharmacotherapy used so far. In our recent studies, we have shown that 4-alkyl-5-aryl-1,2,4-triazole-3-thiones act on the voltage-gated sodium channels and exhibit anticonvulsant activity in an MES (maximal electroshock-induced seizure) and 6Hz test in mice. Previous studies have shown their beneficial toxic and pharmacological profile, but their effect on a living organism during chronic use is still unknown. In the presented study, on the basis of the previously conducted tests and the PAMPA (parallel artificial membrane permeability assay) BBB (blood-brain barrier) test, we selected one 1,2,4-triazole-3-thione derivative-TP-315-for further studies aimed at assessing the impact of its chronic use on a living organism. After long-term administration of TP-315 to Albino Swiss mice, its effect on the functional parameters of internal organs was assessed by performing biochemical, morphological, and histopathological examinations. It was also determined whether the tested compound inhibits selected isoforms of the CYP450 enzyme system. On the basis of the conducted tests, it was found that TP-315 does not show nephrotoxic nor hepatotoxic effects and does not cause changes in hematological parameters. In vitro tests showed that TP-315 did not inhibit CYP2B6, CYP2D6, CYP3A4, or CYP3A5 enzymes at the concentration found in the serum of mice subjected to long-term exposure to this compound.

Mutations of p53 Gene in Canine Sweat Gland Carcinomas Probably Associated with UV Radiation.

INTRODUCTION: Apocrine sweat gland carcinomas (ASGCs) are rare malignant skin tumours in dogs and humans. The literature published so far focuses mostly on the clinico-epidemiological aspect of these tumours, but little is known about their pathogenesis. In this study we aimed to determine whether the p53 gene is involved in the carcinogenesis of the apocrine sweat gland in dogs and whether ultraviolet radiation (UV) is related to it. MATERIAL AND METHODS: Forty canine ASGCs were submitted to laser capture microdissection to isolate neoplastic cells, from which DNA was subsequently extracted. PCR amplification and sequencing of p53 exons 2-8 was then performed, followed by computer analysis of the obtained sequences. RESULTS: Sixteen mutations within the p53 gene were found in 13 tumours. The mutations involved C → T, T → C, G → A, and CC → TT transitions, C → G transversion and adenine deletion, which are gene alteration types known to be related to UV radiation in the process of skin carcinogenesis in humans. Six of the thirteen tumour cases displayed the C → T transitions in the same location in exon 4 and three of the thirteen cases displayed T → C in the same location in exon 5. CONCLUSION: The results of the present study indicate both the participation of the p53 gene and the influence of UV radiation in the formation of ASGCs in dogs.

Study of DNA topoisomerase IIa expression in canine lymphomas and its potential role as a marker of sensitivity to anthracycline-based chemotherapy in dogs.

INTRODUCTION: Canine lymphoma remains one of the most chemotherapy-responsive neoplasia in dogs. Many factors affect the prognosis in dogs treated for lymphoma, but indications for a specific treatment regimen in individual animals with lymphoma are poorly defined. Topoisomerase IIα (TOPIIα) is a key enzyme in DNA replication and a molecular target for TOPIIα inhibitors, including anthracyclines. The aim of this study was to determine the expression of TOPIIα in canine malignant lymphomas. The relationship between TOPIIα expression in canine lymphomas and potential sensitivity of neoplastic cells to anthracycline-based chemotherapy is discussed. MATERIALS AND METHOD: Samples of formalin-fixed paraffin-embedded lymph nodes from 47 dogs with different subtypes of non-Hodgkin's (34 B-cell and 13 T-cell) lymphoma were immunohistochemically labeled with anti-TOPIIα. The number of positive cells and the intensity of the reaction were taken into account in order to assess TOPIIα expression. RESULTS: TOPIIα expression was evident in all cases, although differences in the number of positive cells and intensity of the reaction were demonstrated between B-cell and T-cell lymphoma groups as well as within individual groups. Based on the established scoring system, in the B-cell lymphoma group statistically higher expression of TOPIIα was found compared to the T-cell lymphoma group (P = 0.006). In B-cell lymphoma group moderate (41.18%) and strong (32.35%) TOPIIα expression predominated, whereas among T-cell lymphoma group the majority were cases with a weak (46.15%) TOPIIα expression. CONCLUSION: These preliminary results indicate that further studies are needed to determine the prognostic value of TOPIIα expression with regard to the sensitivity of canine B-cell lymphomas to anthracycline-based chemotherapy regimen. Nevertheless, this study indicates the possibility of choosing the appropriate treatment of canine lymphoma based on TOPIIa expression.

Granular Cell Tumor in a Horse: Multifocal Pulmonary Distribution and Evidence of Autophagy in Tumorigenesis.

Granular cell tumor (GCT) is a soft tissue neoplasm characterized by abundant intracellular eosinophilic granules. The majority of GCTs are benign, although some display malignant behavior. Furthermore, GCTs may mimic other neoplasms. The clinical course and biology of GCTs are poorly understood. Regarding the histogenesis of GCT, a Schwann cell origin is currently favored in light of immunohistochemical and ultrastructural analyses. However, based on literature data, some of the primitive GCTs show non-neural origin; therefore, the histogenesis of this tumor has remained enigmatic. Granular cell tumors can arise in almost any location of the body and typically present as solitary lesions. This study illustrates equine primary GCT with multifocal pulmonary distribution. The presence of GCT in the respiratory tract becomes a diagnostic challenge on initial presentation. The morphologic details of this case are presented. Immunohistochemical evaluation confirmed the neuronal origin of equine GCT and the relation of intracytoplasmic granules formation to an autophagy phenomenon. Most of the discussion is related to GCT nature to help characterize molecular aspects associated with the biological behavior of this tumor and its heterogeneity.

Occurrence and Distribution of Canine Cutaneous Mast Cell Tumour Characteristics Among Predisposed Breeds.

INTRODUCTION: Breed predisposition to cutaneous mast cell tumours (MCT) in a population of dogs in Poland affected by various skin tumours was assessed, and the distribution of MCT characteristics such as histological grading, sex, age, and location, in predisposed breeds was evaluated. MATERIAL AND METHODS: The retrospective epidemiological study included 550 dogs affected by cutaneous MCTs with a reference group of 2,557 dogs diagnosed with other skin tumours. RESULTS: A univariable logistic regression analysis was performed to determine the odds ratios (ORs) with 95% confidence intervals. The risk of high-grade MCTs was the highest for Shar-Peis (OR: 26.394) and American Staffordshire Terriers (OR: 2.897). Boxers (OR: 6.619), Labrador Retrievers (OR: 2.630), French Bulldogs (OR: 2.050), Golden Retrievers (OR: 1.949), and American Staffordshire Terriers (OR: 2.592) were mainly affected by low-grade MCTs. The high risk of MCT was calculated to be at the age of 4-6 years for Labrador Retrievers (OR: 2.686) and 7-10 years for Boxers (OR: 2.956) and French Bulldogs (OR: 9.429). MCTs were significantly more often located on the trunk in French Bulldogs (OR: 4.680), American Staffordshire Terriers (OR: 2.520), and Labrador Retrievers (OR: 1.948). There was no statistically significant correlation between gender and the occurrence of MCTs in the breeds. CONCLUSIONS: The breed-predicated differences in the clinical course of MCTs suggest a genetic background for the tumours.

Immunohistochemical expression of p63 protein and calponin in canine mammary tumours.

The aim of this study was to compare the expression of p63 protein and calponin in terms of their affinity and specificity for myoepithelial cells in canine mammary tumours. The studied material included 10 benign and 32 malignant mammary tumours from female dogs treated with mastectomy. Primary mouse monoclonal antibodies directed against p63 protein clone 4A4 and calponin clone CALP were used in single- and doublestain system of immunohistochemical reaction. The investigations have shown that majority of myoepithelial cells in benign tumours and carcinomas in situ exhibited strong positive labelling for both markers. In other malignant tumours strong immunoreactivity was observed in resting myoepithelial cells (MECs) and hypertrophic myoepithelial cells (HMECs), while the immunoreactivity in spindle-stellate myoepithelial cells (SMECs) and rounded myoepithelial cells (RMECs) was moderate. The granular-diffuse nuclear expression of p63 protein was observed only in myoepithelial cells. In terms of calponin, diffuse cytoplasmic expression was noted not only in myoepithelial cell but also in some stromal fibroblasts and vascular smooth muscle cells. The epithelial cells did not exhibit specific expression of the investigated markers. The obtained results indicate that p63 is a sensitive and more specific marker of myoepithelial cells in canine mammary tumours compared with calponin. These findings suggest that the immunohistochemical analysis peformed with the use of p63 can be a valuable complement of routine histological examinations of canine mammary tumours facilitating identification of tumours with myoepithelial component.

Heteroplasmic Mutations and Polymorphisms in the Cyb Gene of Mitochondrial DNA in Canine Mast Cell Tumours.

AIM: Identification of mutations and polymorphisms in the cytochrome b gene (Cyb) of mitochondrial DNA (mtDNA) in canine mast cell tumours and determinatiion of their association with the process of neoplastic transformation. MATERIALS AND METHODS: The samples comprised tumour tissues and blood obtained from 34 dogs of various breeds. Mutations and polymorphisms in the Cyb gene were detected using amplification and sequencing methods. RESULTS: Heteroplasmic mutations were detected at seven positions of mtDNA in 86% of the individuals. Blood and tumour heteroplasmy were recorded at five nucleotide positions of the Cyb gene, whereas tumour heteroplasmy was detected at two positions. Polymorphisms were detected at 14 Cyb gene positions in in the blood of 91% of dogs with mast cell tumours. CONCLUSION: The presence of numerous mutations and polymorphisms of Cyb in the blood and tumour tissues and the high frequency of heteroplasmy indicate their involvement in the process of neoplastic transformation in dogs.

Elastographic and Morphological Testicular Changes in Hypothyroidism - An Experimental Study.

INTRODUCTION: Methimazole-induced hypothyroidism is a clinical problem in the treatment of hyperthyroidism in people and animals and is an example of metabolic disease that can lead to fertility disorders and can give elastographic testicular changes. MATERIAL AND METHODS: Ultrasound elastography using the Esaote MyLab Twice ultrasound system and a morphological examination of testes were performed in seven methimazole-administered (group E) and seven healthy rats (group C). RESULTS: The elasticity ratio of strains in the scrotal wall of the near-field test area to testicular tissue (ELX-T-RAT) and hardness percentage of strained tissues in the defined area of a testicle (ELX-T%HRD) in group E were statistically significantly lower than in group C. The degree of spermatogenesis was statistically significantly higher in group E than in group C and similarly seminiferous tubule diameters in group E were statistically significantly higher than in group C. Body weight and testicular weight in group E were statistically significantly lower than in group C. CONCLUSION: Changes in the elastographical parameters of testes may result from disorders secondary to hypothyroidism. The usefulness of elastography is noteworthy in the case of evaluation of testis function in patients with some metabolic disorders.

Successful control of disseminated follicular cysts in a dog with low dose isotretinoin.

A case of disseminated cysts in a dog is described. Histopathological examination revealed the presence of follicular infundibular cysts, which were treated with isotretinoin at a dose of 2 mg/kg body weight (BW), q24h for 1 week, followed by a dose of 1 mg/kg BW for 3 months. Symptoms resolved after this course of treatment.

Contrôle réussi de kystes folliculaires disséminés chez un chien à l'aide d'une faible dose d' isotrétinoïne . Nous décrivons un cas de kystes disséminés chez un chien. L'examen histopathologique a révélé la présence de kystes infundibuliformes folliculaires qui ont été traités à l'aide de l'isotrétinoïne à une dose de 2 mg/kg poids corporel (PC), q24h pendant 1 semaine, suivie d'une dose de 1 mg/kg PC pendant 3 mois. Les symptômes se sont résorbés après ce régime de traitement.(Traduit par Isabelle Vallières).

Epidemiological assessment of the risk of canine mast cell tumours based on the Kiupel two-grade malignancy classification.

BACKGROUND: The degree of differentiation of mast cell tumours (MCTs) is the most important feature and reflects the morphological characteristics and metastatic potential of the tumour and its likely response to treatment and the prognosis. The aim of this study was to epidemiologically analyse the risk of MCT development in dogs according to breed, age, sex, size and anatomical location of the tumour using the Kiupel grading system. The analysis involved 492 dogs selected based on a histopathological assessment of 2763 canine skin tumours. A logistic regression analysis was performed to determine the odds ratios (ORs) with 95% confidence intervals. RESULTS: Mast cell tumours accounted for 17.8% of all diagnosed canine skin tumours. The highest risk of high-grade MCTs was noted in the Shar-Pei (OR 28.18, P < 0.001) and Weimaraner (OR 6.45, P = 0.023). The highest risk of low-grade MCTs was determined in the Boxer (OR 6.72, P < 0.001), and Pug (OR 6.13, P = 0.027). The scrotum (OR 31.72, P < 0.001), inguinal area (OR 17.69, P < 0.001) and axilla (OR 6.30, P < 0.001) had the highest risk of high-grade MCTs. The risk of high-grade MCTs increased with age and peaked in the oldest dogs, aged 11-16 years (OR 9.55, P < 0.001). A higher risk of low-grade tumours was noted in younger dogs (aged 4-6 years) (OR 8.54, P < 0.001) and females (OR 1.43, P = 0.001). Statistical analysis further revealed a higher risk of both low (OR 3.47, P < 0.001) and high-grade MCTs (OR 1.71, P = 0.006) in medium-sized dogs. CONCLUSIONS: This study demonstrated relationships between Kiupel grading system and phenotypic traits, age and location of canine MCTs confirming the complex biological nature of this tumour.

Expression of receptor interacting protein 1 and receptor interacting protein 3 oval cells in a rat model of hepatocarcinogenesis.

When apoptosis is suppressed in a neoplastic state, necroptosis may enable an anticancer response. In the present study, the association between apoptosis and necroptosis was assessed in a partial hepatectomy (PH)/diethylnitrosamine (DEN) rat model of hepatocarcinogenesis. Isolated oval cells (OCs) were analysed at 24, 48 and 72 h and at the first and second week of incubation. Phenotypic studies, apoptosis and necroptosis detection and proliferative activity assays were also performed on the OCs. The OCs were isolated from non-neoplastic (PH) and neoplastic (PH/DEN) livers, which expressed receptor interacting protein (RIP) 1 and RIP3. Western blot analysis revealed that the RIP1 and RIP3 expression in the PH/DEN OCs started to increase at 72 h and continually increased to the end of cell culture. Compared with the PH OCs, the cells isolated from PH/DEN rats exhibited significantly less potential for apoptosis (P<0.05). There were a minimal number of apoptotic PH/DEN OCs (2.82±1.1%) at 72 h. In addition, the PH/DEN OCs demonstrated progressive proliferative activity during incubation, which was significantly increased compared with the PH OCs at ≥72 h. The present study revealed that PH/DEN OCs, which trigger hepatic cancer, have a high proliferative activity and suppress apoptosis. It was also observed that, based on the expression of RIP3 and RIP1, necroptosis may be maintained and may serve as an alternative pathway for programmed PH/DEN OC death.