Equus caballus papillomavirus type 2 (EcPV2)-associated benign penile lesions and squamous cell carcinomas.

BACKGROUND: Squamous cell carcinoma is the most common genital, ocular and gastric tumour in horses. Equus caballus papillomavirus type 2 (EcPV2) DNA has been detected in several studies in equine penile squamous cell carcinomas (SCCs) and precursor lesions providing evidence of a causal role of EcPV2 in equine genital SCCs. Recently, EcPV2 E6/E7 nucleic acids were also detected in equine gastric SCCs, but further studies are required to determine the role of EcPV2 infection in the pathogenesis of gastric SCC. EcPV2 nucleic acids have been rarely described in ocular SCCs and precursor lesions. OBJECTIVES: To investigate the presence of EcPV2 nucleic acids with polymerase chain reaction (PCR) and in situ hybridisation (ISH) in penile hyperplasias, papillomas and SCCs in horses and to determine whether EcPV2 nucleic acids can be detected in SCCs affecting other locations, including the stomach, ocular tissues and larynx. METHODS: Twenty-one archival formalin-fixed paraffin embedded (FFPE) tissue samples, including 12 genital lesions comprising penile hyperplasias, papillomas and SCCs, 6 ocular SCCs, 2 gastric SCCs and 1 laryngeal SCC, were screened by PCR and ISH for EcPV2 E6/E7 DNA and mRNA. Archival FFPE tissue samples (eyelid and penile mucosa and preputium) from six horses without a diagnosis or history of neoplastic or papillomavirus-associated disease were included as controls. RESULTS: EcPV2 nucleic acids were detected by PCR and ISH in all genital lesions (12/12) and gastric SCCs (2/2), in two ocular SCCs (2/6) and in one laryngeal SCC (1/1). In control horses, one eyelid sample was positive in PCR but not in ISH. The remaining control samples were negative for EcPV2 E6/E7 nucleic acids in PCR and ISH. CONCLUSIONS: These results further support the role of EcPV2 infection in the development of equine genital SCCs and suggest that EcPV2 infection may also act as a predisposing factor for other SCCs in horses, including gastric, ocular and laryngeal SCCs.

Intravascular papillary endothelial hyperplasia in the lungs of a wild Korean raccoon dog.

A male Korean raccoon dog of unknown age was rescued and placed at the Daejeon Wildlife Rescue Center, Korea. Physical examination revealed severe emaciation and dehydration, as well as thick crusts and alopecia over most of the body. During medical care, the animal died and was submitted for postmortem examination. Firm, brown-red lesions of various sizes were observed on the surface of the lungs. In cross-sections of the lungs, pulmonary vessels were thickened and dilated, with white irregular papillary luminal projections. Histologically, pulmonary blood vessels were severely hyperplastic, characterized by thickened dilated walls and fibrous papillary projections covered with a single layer of endothelial cells (ECs). Hyperplastic fibrous connective tissue was confirmed by Masson trichrome staining. The ECs expressed CD31. We diagnosed the lesion as intravascular papillary endothelial hyperplasia, a unique non-neoplastic reactive process that has not been reported previously in pulmonary vessels of canids, equids, or felids, to our knowledge.

Verminous pneumonia in European hedgehogs (Erinaceus europaeus).

The European hedgehog (Erinaceus europaeus) is a common wildlife species in European countries. Populations are declining due to anthropogenic factors and natural diseases. Verminous pneumonia has been observed as a frequent infectious disease in hedgehogs submitted for diagnostic postmortem examination. This prompted the present in-depth investigation on the lungs of 27 necropsied hedgehogs with confirmed lungworm infections, with or without antiparasitic treatment prior to death. The histological and/or parasitic (fecal samples) examination identified Capillaria aerophila infection in most animals (82%). The parasites were found free in the airway lumen and/or within the airway epithelium, from the larynx to bronchioles. Embedded worms and eggs were associated with epithelial hyperplasia or metaplasia, and long-term inflammation. More than half of the animals (59%) carried Crenosoma striatum, and 41% had a coinfection. C striatum adults were predominantly found free in the lumen of bronchi and bronchioles, and larvae were occasionally seen in granulomas in the pulmonary interstitium, the liver, and the intestine. Independent of the parasite species, a lymphoplasmacytic peribronchitis and, less frequently, interstitial infiltration of eosinophils, neutrophils, and macrophages as well as pneumocyte type II hyperplasia was seen. Interestingly, the extent of pneumonia was not correlated with age, respiratory clinical signs, antiparasitic treatment, or single or coinfection. Verminous pneumonia appeared to be the cause of death in over 25% of the animals, indicating that these parasites not only coexist with hedgehogs but can also be a primary pathogen in this species.

Nodular hyperplasia of lymphoglandular complexes in dogs: A potential diagnostic pitfall for rectal masses.

Lymphoglandular complexes are components of the gut-associated lymphoid tissue that are characterized by submucosal lymphoid aggregates invested by projections of mucosal epithelium. Reports of pathology involving these structures are rare in both human and veterinary literature. Here, the authors report 2 cases of rectal masses excised from dogs following a period of tenesmus and hematochezia. In both animals, the masses were composed of lymphoid tissue closely encompassing tubuloacinar structures. Immunohistochemistry and polymerase chain reaction antigen receptor rearrangement testing demonstrated that the lymphoid population was polyclonal, comprising T and B cells arranged in loosely follicular aggregates centered on the epithelial foci. In light of these findings, a diagnosis of lymphoglandular complex nodular hyperplasia was reported. To the authors' knowledge, this is the first report of this condition in dogs.

Severe bronchiectasis resulting from chronic bacterial bronchitis and bronchopneumonia in a jungle cat.

Bronchiectasis is irreversible bronchial dilation that can be congenital or acquired secondary to chronic airway obstruction. Feline bronchiectasis is rare and, to our knowledge, has not been reported previously in a non-domestic felid. An ~10-y-old female jungle cat (Felis chaus) was presented for evaluation of an abdominal mass and suspected pulmonary metastasis. The animal died during exploratory laparotomy and was submitted for postmortem examination. Gross examination revealed consolidation of the left caudal lung lobe and hila of the cranial lung lobes. Elsewhere in the lungs were several pale-yellow pleural foci of endogenous lipid pneumonia. On cut section, there was severe distension of bronchi with abundant white mucoid fluid. The remaining lung lobes were multifocally expanded by marginal emphysema. Histologically, ectatic bronchi, bronchioles, and fewer alveoli contained degenerate neutrophils, fibrin, and mucin (suppurative bronchopneumonia) with rare gram-negative bacteria. Aerobic culture yielded low growth of Proteus mirabilis and Escherichia coli. There was chronic bronchitis, marked by moderate bronchial gland hyperplasia, lymphoplasmacytic inflammation, and lymphoid hyperplasia. The palpated abdominal mass was a uterine endometrial polyp, which was considered an incidental, but novel, finding. Chronic bronchitis and bronchopneumonia should be considered as a cause of bronchiectasis and a differential diagnosis for respiratory disease in non-domestic felids.

Dermoscopic features of benign sebaceous proliferations in dogs: Description, assessment and inter-observer agreement.

BACKGROUND: Dermoscopy is a useful, noninvasive technique also used to assess sebaceous lesions in humans. Sebaceous hyperplasia, sebaceous adenoma and sebaceous epithelioma are common cutaneous lesions in dogs; however, their dermoscopic features have not been investigated. HYPOTHESIS/OBJECTIVES: The objectives of this study are to describe the dermoscopic features of canine sebaceous lesions and to assess the interobserver agreement on dermoscopic parameters. ANIMALS: Thirty-four lesions excised from 17 client-owned dogs, histologically confirmed as sebaceous proliferations, were included in this study. MATERIALS AND METHODS: Sebaceous lesions were evaluated in vivo at ×10 magnification with a handheld dermoscope. Each dermoscopic image was assessed independently by two ECVD board-certified veterinary referral clinicians and an ECVD resident. RESULTS: Thirty sebaceous hyperplasias, two sebaceous adenomas and two sebaceous epitheliomas were included. Dermoscopically, most lesions (91%) had single or multiple, well-defined, white-yellowish structures composed of grouped ovoid areas (clods). Irregular linear and, less commonly, arborising vessels were detected at the periphery of the yellow lobular-like structures in 93% of sebaceous hyperplasias and in 50% of neoplastic lesions. Erosions were seen in 6% of sebaceous hyperplasias and 50% of neoplastic lesions. Good interobserver agreement was found for white/yellowish clods (k = 0.75), yellow scales (k = 0.83), brown/grey dots (k = 0.80), erosions (k = 0.82) and red/brownish scales/crusts (k = 0.75). There was moderate agreement for fissures (k = 0.48) and vascular pattern (k = 0.51-0.53). CONCLUSIONS AND CLINICAL RELEVANCE: Dermoscopy represents a useful technique to assess sebaceous gland proliferations in dogs, as it is in humans.

In ovo probiotic supplementation promotes muscle growth and development in broiler embryos.

In chickens, muscle development during embryonic growth is predominantly by myofiber hyperplasia. Following hatch, muscle growth primarily occurs via hypertrophy of the existing myofibers. Since myofiber number is set at hatch, production of more muscle fibers during embryonic growth would provide a greater myofiber number at hatch and potential for posthatch muscle growth by hypertrophy. Therefore, to improve performance in broilers, this study investigated the effect of in ovo spray application of probiotics on overall morphometry and muscle development in broiler embryos. For the study, fertile Ross 308 eggs were sprayed with different probiotics; Lactobacillus paracasei DUP 13076 (LP) and L. rhamnosus NRRL B 442 (LR) prior to and during incubation. The embryos were sacrificed on d 7, 10, 14, and 18 for embryo morphometry and pectoralis major muscle (PMM) sampling. Muscle sections were stained and imaged to quantify muscle fiber density (MFD), myofiber cross-sectional area (CSA), and nuclei density. Additionally, gene expression assays were performed to elucidate the effect of probiotics on myogenic genes. In ovo probiotic supplementation was found to significantly improve embryo weight, breast weight, and leg weight (P < 0.05). Further, histological analysis of PMM revealed a significant increase in MFD and nuclei number in the probiotic-treated embryos when compared to the control (P < 0.05). In 18-day-old broiler embryos, myofibers in the treatment group had a significantly smaller CSA (LP: 95.27 ± 3.28 µm2, LR: 178.84 ± 15.1 µm2) when compared to the control (211.41 ± 15.67 µm2). This decrease in CSA was found to be associated with a concomitant increase in MFD (fibers/mm2) in the LP (13,647 ± 482.15) and LR (13,957 ± 463.13) group when compared to the control (7,680 ± 406.78). Additionally, this increase in myofibrillar hyperplasia in the treatment groups was associated with upregulation in the expression of key genes regulating muscle growth including MYF5, MYOD, MYOG, and IGF-1. In summary, in ovo spray application of probiotics promoted overall embryo growth and muscle development in broilers.

TRIM25 participates in the fibrous tissue hyperplasia induced by ALV-J infection in chickens by targeting 14-3-3σ protein.

ALV-J-SD1005 strain was subcutaneously inoculated into the necks of 1-day-old HY-Line Brown chickens and caused severe growth retardation, viremia and subcutaneous fibrosarcomas in the necks of all infected chickens from 14 days post inoculation (DPI) to 21 DPI, and also significantly increased the expressions of TRIM25, P53, etc., but significantly decreased the expressions of 14-3-3σ, etc. Overexpression of chicken TRIM25 (chTRIM25) significantly promoted cell proliferation and improved the expressions of P53, CDC2, and CDK2 tumor factors; and significantly inhibited the expression of 14-3-3σ in ALV-J-SD1005-infected DF1 cells; but knockdown of chTRIM25 caused the opposite effects. The results of co-immunoprecipitation (Co-IP) and confocal microscopy confirmed that chTRIM25 can recognize and bind 14-3-3σ protein in ALV-J-SD1005-infected cells, and they were co-located in the cytoplasm. It can be concluded that chTRIM25 participates in the fibrous tissue hyperplasia induced by ALV-J-SD1005 infections in chickens by binding 14-3-3σ protein and regulating the expressions of 14-3-3σ, P53, CDC2, and CDK2.

Can CT texture analysis parameters be used as imaging biomarkers for prediction of malignancy in canine splenic tumors?

Splenic hemangiosarcoma has morphological similarities to benign nodular hyperplasia. Computed tomography (CT) texture analysis can analyze the texture of images that the naive human eye cannot detect. Recently, there have been attempts to incorporate CT texture analysis with artificial intelligence in human medicine. This retrospective, analytical design study aimed to assess the feasibility of CT texture analysis in splenic masses and investigate predictive biomarkers of splenic hemangiosarcoma in dogs. Parameters for dogs with hemangiosarcoma and nodular hyperplasia were compared, and an independent parameter that could differentiate between them was selected. Discriminant analysis was performed to assess the ability to discriminate the two splenic masses and compare the relative importance of the parameters. A total of 23 dogs were sampled, including 16 splenic nodular hyperplasia and seven hemangiosarcoma. In each dog, total 38 radiomic parameters were extracted from first-, second-, and higher-order matrices. Thirteen parameters had significant differences between hemangiosarcoma and nodular hyperplasia. Skewness in the first-order matrix and GLRLM_LGRE and GLZLM_ZLNU in the second, higher-order matrix were determined as independent parameters. A discriminant equation consisting of skewness, GLZLM_LGZE, and GLZLM_ZLNU was derived, and the cross-validation verification result showed an accuracy of 95.7%. Skewness was the most influential parameter for the discrimination of the two masses. The study results supported using CT texture analysis to help differentiate hemangiosarcoma from nodular hyperplasia in dogs. This new diagnostic approach can be used for developing future machine learning-based texture analysis tools.

Cyclosporine induced generalized hyperkeratosis in a dog.

INTRODUCTION: Cyclosporine is a potent immunosuppressive agent used in veterinary medicine to treat a variety of inflammatory or immune mediated conditions. Many adverse effects are associated with this medication, however most of them rarely occur. A 5-year-old, female intact French bulldog was presented with multiple, multifocally distributed, severe hyperkeratotic and papillomatous/verrucous plaques. The dog was on long-term immunosuppressive treatment with cyclosporine for meningoencephalitis of unknown origin (MUO). It had an history of atopic dermatitis and calcinosis cutis. A papillomavirus infection was excluded by polymerase chain reaction (PCR), and histopathologic analysis revealed a chronic lymphoplasmacytic non-specific dermatitis, perifolliculitis and periadnexitis and focal folliculitis with papillomatous epidermal hyperplasia and orthokeratotic hyperkeratosis. The diagnosis of "cyclosporine-induced epidermal hyperplasia with secondary pyoderma" was made. Cyclosporine was discontinued and as an alternative mycophenolate mofetil was started to control the MUO. An antimicrobial treatment was prescribed for three weeks. After four months, the skin lesions had healed completely. To date after 2 years, the dog is still in remission. The occurrence of hyperplastic lesions associated with cyclosporine therapy have already been described in previous reports. Most of them resemble those of psoriasiform lichenoid dermatitis, although papilloma virus may be detected in some instances. The dog of the present case showed some peculiarities in the histopathological findings, and a papillomavirus involvement was ruled out with PCR. Like observed in a previous report, there was no correlation between cyclosporine blood level and the severity of dermatological changes. A discontinuation of cyclosporine resulted in complete healing in 4 months. This case highlights the importance of regular monitoring and follow-ups in patients on immunosuppressive therapy. Even rare side effects should always be considered in these cases.

INTRODUCTION: La cyclosporine est un puissant agent immunosuppresseur utilisé en médecine vétérinaire pour traiter une variété de conditions inflammatoires ou à médiation immunitaire. De nombreux effets indésirables sont associés à ce médicament, mais la plupart d'entre eux se produisent rarement. Un bouledogue français intact, âgé de 5 ans, a été présenté avec de multiples plaques hyperkératosiques et papillomateuses/verruqueuses sévères, réparties de manière multifocale. Le chien suivait un traitement immunosuppresseur à long terme à base de cyclosporine pour une méningo-encéphalite d'origine inconnue (MUO). Il avait des antécédents de dermatite atopique et de calcinosis cutis. Une infection à papillomavirus a été exclue par réaction en chaîne par polymérase (PCR) et l'analyse histopathologique a révélé une dermatite chronique lymphoplasmocytaire non spécifique, une périfolliculite et une périannexite ainsi qu'une folliculite focale avec hyperplasie épidermique papillomateuse et hyperkératose orthokératosique. Le diagnostic d'¼hyperplasie épidermique induite par la cyclosporine avec pyodermie secondaire¼ a été posé. La cyclosporine a été stoppée et on a commencé à administrer du mycophénolate mofétil comme alternative pour contrôler l'OMU. Un traitement antimicrobien a été prescrit pendant trois semaines. Après quatre mois, les lésions cutanées étaient complètement guéries. À ce jour, après deux ans, le chien est toujours en rémission. L'apparition de lésions hyperplasiques associées au traitement par la cyclosporine a déjà été décrite dans des rapports précédents. La plupart d'entre elles ressemblent à celles de la dermatite lichénoïde psoriasiforme, bien que le virus du papillome puisse être détecté dans certains cas. Le chien du cas présent présentait quelques particularités dans les résultats histopathologiques et une implication du papillomavirus a été exclue par PCR. Comme observé dans un rapport précédent, il n'y avait pas de corrélation entre le taux sanguin de cyclosporine et la sévérité des altérations dermatologiques. L'arrêt de la cyclosporine a permis une guérison complète en 4 mois. Ce cas souligne l'importance d'une surveillance et d'un suivi réguliers des patients sous traitement immunosuppresseur. Les effets secondaires, même rares, doivent toujours être pris en compte dans ces cas.

Contrast-enhanced CT features of pyloric lesions in 17 dogs: Case series.

Pyloric outflow obstructions can be caused by several types of lesions. When a thickened gastric wall and pyloric mass are detected, malignant neoplasia must be differentiated from chronic hypertrophic pyloric gastropathy. CT can characterize gastric tumors. However, based on the authors' review of the literature, there is limited information about the CT findings of pyloric lesions. The purpose of this retrospective case series study was to assess the CT findings of canine pyloric lesions. The following CT parameters were recorded: anatomical area, involved area, lesion shape, growth patterns of wall thickening lesions, enhancement pattern of the lesion in the early and delayed phases, lymphomegaly, and pulmonary metastasis. Seventeen dogs were included in this study and had the following final diagnoses: hyperplasia (five dogs), adenoma (five dogs), adenocarcinoma (three dogs), gastrointestinal stromal tumor (GIST; two dogs), polyposis (one dog), and pyogenic granuloma (one dog). Hyperplasia, adenoma, and polyposis formed mass lesions that involved the mucosal layer. Lymphomegaly was detected in two Jack Russell terriers with hyperplasia; however, the causes were unknown because we did not perform biopsies. All adenocarcinomas formed wall-thickened lesion that involved the outer layer, with lymphomegaly. All GISTs formed mass lesion that involved the outer layer. The pyogenic granulomas formed symmetric wall-thickened lesion that involved the mucosal and outer layers. CT facilitated the characterization of canine pyloric lesions using contrast enhancement, based on the involved area and lesion shape. However, polyposis may require caution in diagnosis based on CT findings alone.

Ocular lesions of captive cephalopods.

Ocular lesions are uncommonly reported and described in invertebrate species. In this study, cases from 2 diagnostic laboratories, in which lesions were noted in 33 diagnostic specimens from various species of cephalopods, including octopuses, squid, nautiluses, and cuttlefish, were reviewed. Clinical information and gross lesions were described in a minority of cases. The most common lesion was inflammation of varying severity and was most commonly within the anterior uvea (iris and ciliary papilla), followed by the posterior chamber and lens. More than half of the cases with inflammation had concurrent hyperplastic lesions of the iris and ciliary papilla, including posterior iris epithelial hyperplasia, cystic adenomatous hyperplasia, and/or posterior epithelial cysts. The most common clinical observation was cloudy eyes, which correlated histologically to anterior uveitis in all cases where it was documented. Dermatitis and cutaneous ulceration were the most frequent comorbidities in cases where clinical information was available.

[Multiple hyperplastic colon polyps in a cow]. / Multiple hyperplastische Kolonpolypen bei einem Rind.

INTRODUCTION: Reports on bovine colon polyps are rare. The present report demonstrates macro- and microscopically hyperplastic colon polyps of a seven-year-old German Simmental cow. Differential diagnoses (adenoma and adenocarcinoma) and aetiology are discussed. Even in cattle, intestinal polyps should be considered as a cause of intussusception.

INTRODUCTION: Les rapports concernant des polypes du colon chez les bovins sont rares. Le présent rapport fait état de polypes du côlon macro- et microscopiquement hyperplasiques chez une vache Simmental allemande de sept ans. Les diagnostics différentiels (adénome et adénocarcinome) et l'étiologie sont discutés. Même chez les bovins, les polypes intestinaux doivent être considérés comme une cause d'invagination.

Adenomatous Hyperplasia of Bowman's Capsule Epithelium in a Dog with Metastatic Nasal and Hepatic Neuroendocrine Carcinoma.

A 12-year-old spayed Shiba dog with a nasal neuroendocrine carcinoma and multiple hepatic nodules was necropsied. Histologically, proliferated blast cells with a monolayer or multilayered structure were observed in the kidney. This blast cell proliferation extended from Bowman's capsule epithelium to the proximal tubule in approximately 3% of nephrons. Immunohistochemistry revealed that blast cells were positive for vimentin, Wilm's tumour protein 1 (WT1), paired box 2 (PAX2) and CD10, but negative for cytokeratin (CK) AE1/AE3, CK19, CAM5.2, synaptophysin and chromogranin A. On the basis of these findings, adenomatous hyperplasia of Bowman's capsule epithelium was diagnosed. Multiple yellowish‒white nodules (1-3 cm) were found in the liver and diagnosed as neuroendocrine carcinoma with metastases to the lungs, adrenal glands and pancreaticoduodenal lymph nodes.

Assessment of the possibility of using biomarkers (CCL11 and TGF-beta 1) in the diagnosis of prostate gland hyperplasia in dogs.

Prostatic hyperplasia (PH) is the most common reproductive disorder in dogs and can lead to discomforting problems such as haematuria, urinary incontinence, constipation, difficulty in defecating and stiffness of the hind limbs. The diagnosis of PH is nowadays based on digital rectal examination (DRE), ultrasonography (US) and radiography (X-ray). However, markers associated with PH are barely used for diagnostic purposes. Recently, there have been reports on the use of certain biomarkers for diagnosing PH in dogs such as canine PSA (Prostate Specific Antigen), microRNA and vascular endothelial growth factor (VEGF). Nevertheless, it has been generally accepted that these biomarkers play only an auxiliary role. Accordingly, the aim of our study was to evaluate the usefulness of the CCL11 (eotaxin-1) and TGF-beta 1 markers, which are used in the diagnosis of prostate diseases in humans, in case of dogs with PH. The study was carried out on 40 dogs of different breeds divided into three groups. Group I (n = 9) comprised dogs up to 5 years of age without changes indicative of PH. Group II (n = 17) included dogs aged 5-10 that were examined and diagnosed with (PH) and Group III (n = 14) which consisted of dogs over 10 years of age who were also diagnosed with PH. The study demonstrated that CCL11 levels did not differ significantly between the study groups and the median levels were 7.27 pg/mL, 7.57 pg/mL, 6.81 pg/mL, and IQR ranges 1.55 pg/mL, 1.74 pg/mL, 2.32 pg/mL, respectively. In contrast, TGF-beta 1 levels were detectable only in 6 dogs of group III and averaged the median of 28.86 pg/mL, IQR ranges 10.07 pg/mL. The study proved that CCL11 and TGF-beta 1 markers are of a limited use when diagnosing PH in dogs as no significant correlation related to age, body weight or prostate size was found.

Nodal T-zone lymphoma and T-zone hyperplasia in dogs.

T-zone lymphoma (TZL) is an indolent, nodal lymphoma that has been clinically characterized in detail in dogs, and T-zone hyperplasia (TZH) is a hyperplastic change in lymph nodes associated with antigen processing. In some cases, histopathological features of TZL and TZH are similar, and are difficult to differentiate by morphology alone. Since there have been few publications characterizing their immunohistochemical profiles, histological, immunohistochemical, and clonality examinations were performed using formalin-fixed paraffin-embedded samples of canine lymph nodes with TZL (14 cases) and canine lymph nodes with TZH associated with nonlymphocytic tumors (10 cases). Immunohistochemically, small- to medium-sized lymphocytes of TZL were immunopositive for CD3, CD5, and HLA-DR, and negative for CD45, FOXP3, and granzyme B (GRB) in all cases. Among these 14 cases, 11 were immunopositive for CD8 and 1 was CD20 positive. Paracortical lymphocytes in TZH were diffusely immunopositive for CD3, CD5, and CD45, with scattered immunopositivity for CD8, HLA-DR, FOXP3, and GRB, and negative for CD20 in all cases. A clonal TCR gene rearrangement was detected in 13/14 TZL and none of the TZH cases. The present study revealed that TZL is a clonal proliferation of monomorphic CD8+CD45-GRB- T cells, while TZH consists of an immunophenotypically heterogenous population of CD45+ T cells that are variably positive for CD8 and FOXP3. These results suggest that canine TZL is a clonal proliferation of naïve or premature cytotoxic T cells. Regarding TZH, variable immunopositivity for cytotoxic and regulatory T-cell antigens may reflect immune responses to a variety of regional neoplastic lesions.

Canine and feline in situ mammary carcinoma: A comparative review.

Carcinoma in situ of the breast is a well-known entity in humans. In veterinary medicine, particularly in canine and feline mammary literature, there is no agreement whether the term in situ should be used to indicate a specific carcinoma histotype or the noninvasive status of a carcinoma of any histotype. Moreover, in the most recent histologic classification of mammary tumors published by the Davis-Thompson Foundation, it is suggested to abandon the term carcinoma in situ given the lack of standardized criteria defining this entity, replacing it with epitheliosis or ductal/lobular hyperplasia with severe atypia. This publication presents a critical review of the term in situ in human and veterinary medicine considering the evolution of the term over the years and its heterogeneous use by different authors, including variations in immunohistochemical markers for classification. This review aims to point out the lack of uniformity in the nomenclature and classification issues in veterinary medicine regarding the use of the term in situ, laying the ground for a process of standardization in future publications.

Rat age-related benign prostate hyperplasia is concomitant with an increase in the secretion of low ramified α-glycosydic polysaccharides.

This work analysed the expression of prostate polysaccharides in rats with age-related benign prostatic hyperplasia (BPH) for a better understanding of the possible relationship between prostate polysaccharides secretion and BPH onset. For this, prostatic glands from 1 month-old, 3 months-old, 6 months-old and 12 months-old Sprague-Dawley rats were processed in order to identify their overall polysaccharide content. Additionally, serum testosterone was also determined. One-month old rats showed significantly (P < 0.05) lower testosterone levels (0.77 ng/mL±0.12 ng/mL) compared with the other groups, which showed no significant difference among them. PAS staining showed positive polysaccharides markings in both the prostatic lumen and inside of luminal prostatic cells in all groups. Semiquantitative analysis of intraluminal PAS showed that one month-old rats had significantly (P < 0.005) lower PAS intensity when compared with all other groups (100.0 ± 0.5, arbitrary units vs. 107.3 ± 0.6, arbitrary units in 3 months-old ones), whereas 12 months-old ones showed significantly (P < 0.005) higher values when compared with all other groups (133.6 ± 3.5, arbitrary units in 12 months-old rats vs. 108.6 ± 1.4, arbitrary units in 6 months-old ones). The PAS + content practically disappeared when tissues were pre-incubated with either α-amylase or amyloglucosidase, regardless of a previous incubation with proteinase K. Incubation of prostate extracts from 12 months-old rats for 2 h with α-amylase yielded a significantly higher amount of free glucose (1.47 nmol/mg protein±0.23 nmol/mg protein vs. 0.32 nmol/mg protein±0.01 nmol/mg protein in untreated extracts). Similar results were obtained when extracts were pre-incubated with amyloglucosidase. Contrarily, pre-incubation with N-glycosidase induced a significantly (P < 0.05), much lower increase of free glucose. Pre-treatment with proteinase K did not significantly modify these results, which indicate that BPH is related to an increase in the secretion of low ramified ductal α-glycosydic polysaccharides that were not protected against lysis by any type of protein protective core. These changes seem to not be related with concomitant variations in serum testosterone levels.

Natural SARS-CoV-2 Infection in a Free-Ranging Black-Tailed Marmoset (Mico melanurus) from an Urban Area in Mid-West Brazil.

The emergence of spillover pathogens such as SARS-CoV-2 is a risk to vulnerable human populations. We report natural SARS-CoV-2 infection in a free-ranging adult female black-tailed marmoset (Mico melanurus) from an urban area of Cuiabá, Mato Grosso State, Brazil. The animal was found after a motor vehicle collision without previous clinical history. Necropsy confirmed polytrauma. Severe multifocal to coalescent haemorrhage and mild multifocal peribronchial lymphocytic hyperplasia were seen in lung sections. The alveolar septa were multifocally expanded by a few lymphocytes. Mild lymphocytic periportal hepatitis and interstitial nephritis were found. The lymphoid nodules of the large intestine showed marked lymphocytic hyperplasia. Infection by SARS-CoV-2 was established by viral RNA detection in a pool of nasopharyngeal and oropharyngeal swabs and liver samples. Immunohistochemistry detected the viral nucleocapsid protein in sections of lung, liver, spleen, lymph nodes and large intestine, and spike protein antigen in lung tissue. This is the first report of naturally occurring SARS-CoV-2 infection in a New World monkey. Platyrrhine species should be included as potential hosts of natural infection of SARS-CoV-2.

Poisoning by Nierembergia veitchii: Effects on vascular smooth muscle cells in the pathogenesis of enzootic calcinosis.

Vascular mineralization is a hallmark of enzootic calcinosis. Histopathological, ultrastructural, and immunohistochemical investigations were performed on the external carotid arteries of seven sheep naturally poisoned by Nierembergia veitchii. Histologically, moderate to marked hyperplasia of the tunica intima was observed without mineralization. The tunica media exhibited mild to severe mineralization and osteochondroid metaplasia. Sheep with enzootic calcinosis showed arterial overexpression of osteopontin and tissue-nonspecific alkaline phosphatase and immunolabeling for osteonectin and osteocalcin in both intima and media layers of the tested arteries. The main ultrastructural finding in the tunica media was a marked phenotypic change of vascular smooth muscle cells from a contractile phenotype (VSMC-C) into a synthetic phenotype (VSMC-S). In the tunica media, VSMC-S produced matrix and extracellular vesicles, forming mineralizable granules associated with arterial mineralization. VSMC-S were also present in the tunica intima, but matrix and extracellular vesicles and mineralization were not observed. The absence of matrix and extracellular vesicles in the intimal hyperplasia, even in the presence of noncollagenous bone proteins, tissue-nonspecific alkaline phosphatase, and vitamin D receptors, reinforces the hypothesis that the presence of matrix and extracellular vesicles are crucial for the development of vascular mineralization in enzootic calcinosis. It is proposed that the two different VSMC-S phenotypes in calcinosis are due to the expression of at least two genetically different types of these cells induced by the action of 1,25(OH)2D3.