Infection with different Neospora caninum strains causes differences in the glycosylation pattern in the uteri and placentae of Neospora caninum-infected heifers.

Neospora caninum is an obligate intracellular parasite that causes abortion in ruminants. Different strains produce differences in the severity of disease outcomes. These differences may cause physiological or pathological changes in cells, modifying the intercellular interactions and intracellular transport pathways that could be evidenced by identifying the terminal sugars. This study aimed to characterize the oligosaccharide pattern in the bovine placenta and uterus after infection with tachyzoites of three different strains of N. caninum (Nc-1, Nc-6 Argentina and Nc Spain-7) during early gestation. Fourteen heifers were inoculated intravenously on day 70 of gestation with 2 × 108 N. caninum tachyzoites and samples of placentae and uteri were analysed by histology and lectin histochemistry. In the infected groups, severe placentitis was associated with changes in lectin binding in the vascular endothelium by Lens culinaris agglutinin (LCA), Pisum sativum agglutinin (PSA) and Ricinus communis I (RCA-I) lectins, in the epithelial cells of the endometrial glands by RCA-I, Dolichos biflorus agglutinin (DBA), succinylated wheat germ agglutinin, peanut agglutinin (PNA), concanavalin-A (CON-A), LCA, PSA and Phaseolus vulgaris erythroagglutinin (PHA-e), and in the trophoblast layer by PNA, CON-A, LCA, PSA, PHA-e, soybean agglutinin, RCA-I, DBA and Bandieraea simplicifolia agglutinin (BSA-I). The results suggest that N. caninum causes changes in the glycosylation pattern in the maternofetal interface tissues and might cause abortions in early gestation due to changes in the cellular structure of the placenta.

Altered E-cadherin/ß-catenin expression in feline cutaneous squamous cell carcinomas.

Cutaneous squamous cell carcinoma (CSCC) is the most common malignant skin tumour in cats and the nature of the molecular mechanisms involved is poorly defined. Included among the molecular mechanisms in human and canine CSCCs is altered expression of E-cadherin/ß-catenin. This study aimed to explore the immunohistochemical expression pattern of E-cadherin and ß-catenin in 43 samples of feline CSCC by using a tissue microarray to elucidate whether expression of these molecules is dysregulated. Membrane expression of E-cadherin and membrane and cytoplasmic expression of ß-catenin were significantly reduced in the CSCCs. Cytoplasmic expression of E-cadherin and nuclear expression of ß-catenin were also found in some CSCCs. These findings indicate that altered expression of E-cadherin and ß-catenin is a frequent event in feline CSCCs, suggesting that these molecules play an important role in acquisition of the malignant phenotype in feline patients with CSCC. The results also suggest the existence of a subpopulation of feline patients with CSCC in which the Wnt pathway may contribute to epidermal carcinogenesis.

Characterization of lesions of nutritional congenital goitre in cattle.

There are few studies that classify and characterize the morphometric and immunohistochemical features of goitre in bovine thyroid glands (TGs). We investigated 39 bovine TGs (fetuses [9], stillbirths [18], neonates [12]) born to dams with low T4 hormone levels and no iodine supplementation and 10 (fetuses [3], stillbirths [3], neonates [4]) born to dams with normal T4 levels and supplemented with iodine. Body weight (BW), TG weight (TGW), TGW:BW ratio and histological lesions were determined. The TGs were classified histopathologically as normal gland (G0), mild goitre (G1), moderate goitre (G2) or severe goitre (G3). Various morphological and morphometric parameters were calculated from microscopic images using image analysis software. Immunohistochemistry was performed to detect proliferating cell nuclear antigen (PCNA). There were significant differences in the TGW:BW ratio among groups (P <0.05): 0.3 ± 0.1 in G0, 0.5 ± 0.3 in G1, 0.8 ± 0.3 in G2 and 1.3 ± 0.7 in G3. In G0, large homogeneous follicles with eosinophilic colloid were seen. In the groups with lesions (G1, G2 and G3), heterogeneity in follicle shape and size, height and area of thyroid follicular cells, height of thyroid follicular epithelium and PCNA immunolabelling were directly related to histopathological grade, with significant differences among groups (P <0.001), gradually increasing from G1 to G3 compared with G0. The TGW:BW ratio and histological grade were positively correlated (P = 0.008).

Determination of ptaquiloside in ten species of Pteris in northwestern Argentina.

The toxic effect of ferns of the genus of Pteris in bovines is caused by ptaquiloside, the main carcinogenic toxin. In this study, ten species of Pteris fern in different phenologic stages and plant conditions were collected in northwest Argentina. The phytochemical analysis showed the presence of Pt in the recent collected samples (adults and young plants) but not in the herbarium specimens. The results show a great variation of Pt concentration that depends on the phenologic stage, plant condition, and collection site. Pt was measured in 6-4326 µg/g concentration, with a mean concentration of 644 µg/g. No Pt was detected in eight species of Pteris collected from herbarium samples; such results may be a false negative. It is important to notice that analysis of herbarium samples for Pt may not be a reliable method to determine its presence. It is important to further understand the potential toxicity caused by these ferns because of their effect on animals, public health, and the environment.

Ovarian changes and development of the branchial placenta occurring in Jenynsia lineata (Cyprinodontiformes, Anablepidae).

In viviparous teleosts, intraovarian gestation occurs intrafollicularly, as in poeciliids, or intraluminally, as in goodeids and anablepids. Furthermore, there are two different forms of embryonic nutrition: lecithotrophy and matrotrophy; depending on the species, these can be exclusive or coexist during gestation. In matrotrophic species, nutrients are transmitted from the mother to the embryo and are especially important in species with intraluminal gestation. Jenynsia lineata is a South American viviparous teleost with intraluminal gestation, characterized by eggs with scarce yolk, which is resorbed when embryos are 6 mm long, thus developing a branchial placenta. Using histological, histochemical, and immunohistochemical techniques, the present study describes the characteristics and changes of the ovarian mucosa in J. lineata during gestational and nongestational phases, and analyzes the embryonic pharyngeal epithelium in the branchial placenta. The ovaries of 30 adult female specimens were processed using histological techniques and stained with hematoxylin-eosin, Masson's trichrome, and Alcian Blue pH 2.5/periodic acid Schiff reagent. To detect cell proliferation, we used antiproliferating cell nuclear antigen antibody. In nonpregnant females, eosinophilic granular cells (EGCs) and lymphocytes were identified in the lamina propria of the tunica mucosa, and melanomacrophage centers (MMCs) and fibroblasts were identified adjacent to tissue debris in the ovarian folds'. In the cellular debris, an embryo in resorption was observed. In pregnant females, the ovarian mucosa has thin vascularization branches entering the opercular chamber of the embryos, in close contact with the forming gill processes, thereby establishing a branchial placenta. Active cell replacement was observed in these ovarian branches. The identification of fibroblasts, lymphocytes, EGCs, and MMCs adjacent to tissue debris could indicate that these cell types are involved in the embryonic resorption process. Considering the new data obtained in this study on the branchial placenta of J. lineata, we conclude that cell proliferation could be involved in the development of maternal-embryonic interaction.

I W Rowlands, Barbara J Weir and the biology of the hystricomorph rodents.

In brief: Current research on the genomics, ecology and reproductive biology of hystricomorph rodents relies on the pioneering studies of B J Weir and I W Rowlands. We show the enduring influence of a symposium on hystricomorph biology held 50 years ago. Abstract: The rodent suborder Hystricomorpha comprises seven families from Africa and Asia and ten from South America, where they have undergone an extensive radiation and occupy a variety of biomes. Although the guinea pig was a common laboratory rodent, little was known about reproductive biology in the other species until the ambitious research programme of Barbara Weir and her mentor I W Rowlands. Much of their work and of others then in the field was summarized at a symposium held 50 years ago at The Zoological Society of London. Currently, there is a resurgence of interest in the reproductive biology of the South American species. Compared to other rodents, unique features include a long gestation, a long oestrous cycle, a tendency to form accessory corpora lutea and a vaginal closure membrane. There is a distinctive placental structure, the subplacenta. Most give birth to precocial young. Individual species exhibit peculiarities such as polyovulation, systematic fetal loss and an active female prostate. Here, we highlight the achievements of Barbara Weir and show how her legacy has been sustained in the twenty-first century by South American scientists.

Placental glycotype of the caviomorph rodent Lagostomus maximus and its evolution within Eutheria.

The main evolutionary milestone in the oviparity-viviparity transition is placentation. The placenta is an organ with great morphological diversity among eutherians. The expression of different glycosidic residues (Gr) in the near-term placenta constitutes its glycotype. In this study, the expression of different Gr was determined by lectin histochemistry in early, midterm, and near-term placentas of the plains viscacha (Lagostomus maximus), a caviomorph rodent with the highest poliovulatory rate and embryonic resorption rate among eutherians. Besides, a matrix with the expression of each Gr in the exchange trophoblast of viscacha and other eutherians was constructed to map and infer phylogenetic and evolutionary relationships. Between early, midterm, and near-term placentas, variations in the pattern expression of Gr were observed. The glycotype of the near-term placenta is composed of a high diversity of Gr. Reconstruction of the ancestral state for each Gr present in the near-term placenta showed a diverse scenario: some sugars were common to the species of Placentalia included in this study. In the analyzed species with synepitheliochorial and epitheliochorial placentas, no differential glycosylation patterns between them were observed. In species with invasive placentas, such as the endotheliochorial placentas of Carnivora, some common Gr were detected among them, while others were species-specific. In species with hemochorial placenta, the same Gr are shared. Particularly, in the viscacha greater differences with species of the Hominidae and even Muridae families were observed. Nevertheless, greater similarities with other caviomorph rodents were detected. Placental glycotype of each species constitutes an excellent tool to achieve phylogenetic and evolutionary inferences among eutherians.

Persistent activation of the mammalian target of rapamycin signalling pathway in cutaneous squamous cell carcinomas in cats.

BACKGROUND: Cutaneous squamous cell carcinoma (CSCC) represents the most common malignant tumour of the feline skin. Emerging evidence suggests that the phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signalling pathway may represent a potential target for pharmacological intervention in human and canine CSCC. HYPOTHESIS/OBJECTIVES: The present study aimed to explore the expression pattern and status of activation of relevant signalling proteins of the PI3K/Akt/mTOR signalling pathway in feline CSCC. METHODS AND MATERIALS: The expression of pEGFRTyr1068 , pAktSer473 , pS6Ser235/236 combined with Ki-67, and the tumour suppressor protein PTEN was evaluated by immunohistochemical analysis in 45 samples of feline CSCC, using a tissue microarray. RESULTS: The immunodetection using phosphospecific antibodies to detect the activated forms of signalling proteins showed that the PI3K/Akt/mTOR signalling pathway is frequently activated in feline CSCCs, and may be independent of the activation of EGFR. The results also showed that PTEN expression is not significantly altered in feline CSCCs. CONCLUSIONS AND CLINICAL IMPORTANCE: Our study shows that the persistent activation of the PI3K/Akt/mTOR signalling pathway represents a key event in feline CSCC, pointing to this signalling pathway being a potential therapeutic target in feline patients with CSCC.

Gill morphology and morphometry of the facultative air-breathing armoured catfish, Corydoras paleatus, in relation on aquatic respiration.

The Neotropical armoured catfish Corydoras paleatus is a facultative air-breathing teleost commonly exported as ornamental fish. In this species, air breathing enables it to survive and inhabit freshwater environments with low oxygen levels. Therefore, it is important to analyse the gills from a morphological aspect and its dimensions in relation to body mass with reference to aquatic respiration. For that, the gills were analysed using a stereoscopic microscope for morphometric studies, and structural and ultrastructural studies were carried out to compare the four branchial arches. Furthermore, two immunohistochemical techniques were used to locate and identify the presence of a Na+ /K+ pump. The characterization of the potential for cell proliferation of this organ was assessed using an anti-PCNA antibody. The results show that gills of C. paleatus present some characteristics related to its diet and lifestyle, such as the limited development of gill rakers and the abundance of taste buds. In addition, other special features associated with the environment and bimodal breathing were observed: scarce and absent mucous cells (MCs) in the gill filaments and branchial lamellae, respectively, and the localization of mitochondria-rich cells (MRCs) covering the basal third of the branchial lamellae, which reduces the gill respiratory area. A peculiar finding in the gill epithelium of this armoured catfish was the presence of mononuclear cells with sarcomeres similar to myoid cells, whose functional importance should be determined in future studies. Finally, in C. paleatus, the interlamellar space of gill filaments is an important site for cell turnover and ionoregulation; the latter function is also performed by the branchial lamellae.

Photosensitization Induced by Heterophyllaea pustulata in Goats: Sequential Development of Skin Lesions.

Five adult Saanen goats received a single oral dose of Heterophyllaea pustulata containing 42.25 µg/kg rubiadin (anthraquinone) and 3 adult goats were untreated controls. All goats were exposed to sunlight and sequential ear skin biopsies were collected before treatment and at 32 hours, 3 days, 8 days, and 15 days after treatment. Changes at 32 hours after dosing included epidermal spongiosis, single cell death and acantholysis, an increased BAX/BCL-2 protein ratio, and dermal edema. Lesions at day 3 included epidermal and adnexal necrosis, crust formation, and acanthosis. Acanthosis, hyperkeratosis, and dermal fibrosis and neovascularization were present at day 15. The pro-apoptotic (BAX)/anti-apoptotic (BCL-2) protein ratio increased at 32 hours, whereas epidermal and dermal PCNA immunolabeling increased between days 8 and 15 after treatment. The cutaneous lesions were consistent with sunlight-induced damage, and the occurrence in treated but not control goats indicates photosensitization.

Prenatal development in Lagostomus maximus (Rodentia, Chinchillidae): A unique case among eutherian mammals of physiological embryonic death.

Embryonic death followed by resorption is a conserved process in mammals. Among the polyovular species, Lagostomus maximus (plains viscacha) constitutes a model of early and physiological embryonic death, since out of a total of 10-12 implants, 8-10 are resorbed during early/intermediate gestation, surviving are only the most caudal implantations of each uterine horn. This regular reproductive event is unique to this species, but many characteristics of the implantations during the early gestation of L. maximus, when embryonic death processes begin are unknown. The aim of the present work was to analyze the implantation sites of this species using morphological, morphometric, histochemical, lectinhistochemical, and immunohistochemical techniques to infer the possible causes of this event. Macroscopically, the length and width of the implantation sites significantly increased in a craniocaudal direction. Histochemically, the implantation sites did not differ in the expression of glycoconjugates and glycosidic residues. Furthermore, no variations were observed in cell renewal, hormone receptor expression, and decidualization. Both the glandular and vascular areas of the implantation sites significantly increased in the craniocaudal axis. Some necrotic cells and an inflammatory response with a predominance of lymphocytes and fibrin were observed in the cranial and middle but not in the caudal implantation sites. We conclude that signs of embryonic death and resorption are already observed in the early gestation of L. maximus. Our results reaffirm the hypothesis that postulates the key potential role of uterine glands and blood vessels in the gestation of the species, with emphasis on embryonic death. This pattern of embryonic death in L. maximus makes this species an unconventional mammalian model, which adds to the peculiarities of polyovulation (200-800 oocytes/estrus) and hemochorial placentation.

Structure of the gonoduct of the viviparous teleost Cnesterodon decemmaculatus (Jenyns, 1842) (Poeciliidae).

During embryogenesis, teleost females do not develop Müllerian ducts, which form the oviducts in all other vertebrates. Thus, when they reach sexual maturity they do not have oviducts. In viviparous teleosts, the lack of oviducts means that the development of the embryos occurs as an intraovarian gestation, unique among vertebrates. The ovary is an unpaired hollow organ whose cavity is continuous with the caudal portion, the gonoduct, characterized by the absence of germinal cells, which opens to the exterior at the gonopore. The gonoduct attains essential function as a barrier between the germinal region of the ovary and the exterior during all reproductive stages. This study describes the functional morphology of the gonoduct in the viviparous teleost Cnesterodon decemmaculatus during non-gestation (previtellogenesis and vitellogenesis) and gestation. The ovaries were processed using histological techniques and stained with hematoxylin-eosin, and periodic acid Schiff. The gonoduct has two regions: cephalic and caudal, and is formed by three histological layers, which are, from inside to the periphery: (a) tunica mucosa; (b) tunica muscularis; and (c) tunica serosa. In the cephalic region there are mucosal folds extending into the lumen and forming a structure similar to a cervix. The histology of the gonoduct indicates essential functions, that is, (a) the control of the luminal diameter in the limit to the germinal region of the ovary by the presence of a cervix; (b) during insemination the gonoduct receives the spermatozoa, may store and transport them to the germinal region; (c) the presence of melano-macrophage centers indicates support of immunological processes, especially during gestation when these centers increase in size; (d) production of exocrine secretions; and (e) it is the birth canal, internally lined by an ciliated epithelium and surrounded by smooth musclesboth tissues supposedly supporting the birth process.

Comparison of the structural and ultrastructural characteristics of the female prostate between pregnant and non-pregnant plains viscacha (Lagostomus maximus).

Some years ago, our group reported the presence of the female prostate in all the studied females of the plains viscacha (Lagostomus maximus). The goal of the present study was to characterize and compare the female prostate gland between adult pregnant and non-pregnant plains viscacha using histochemical, lectin-histochemical and immunohistochemical techniques, as well as optic and electron microscopy. Structurally, alveoli are lined by a simple epithelium formed by different cell types: basal cells, secretory cells in different stages of the secretory cycle and cells of clear cytoplasm. Secretory cells are the most abundant cell type, differing between them depending on the quantity and electron-density of their granules. The basal cells are less abundant and are responsible for the renewal of the alveolar epithelium. Likewise, other cells with secretory morphology were found in all the studied females; these have a clear cytoplasm, few granules and mitochondria. It could be considered that they are degranulated secretory cells or that they have partially released their granules. The stroma of the organ is formed by connective tissue and smooth muscle fibers, which are immunohistochemically evidenced against desmin. Histochemical and lectin-histochemical analysis revealed the presence of different glucidic residues in the different cell types. No structural, histochemical, lectin-histochemical, and ultrastructural differences were observed between pregnant and non-pregnant females of plain viscachas, except for the expression of some lectins. The paraurethral gland of Lagostomus maximus can be used as a model for studying the gland in other species since its structural and ultrastructural characteristics do not depend on the hormonal status of the female.

Making a parrot zygodactyl foot: Osteology and morphogenesis of the tarsometatarsus in the monk parakeet (Myiopsitta monachus).

The tarsometatarsus conformation and foot types in birds are unique traits within vertebrates. We investigate how the tarsometatarsus and the zygodactyl foot are formed during development in the monk parakeet (Myiopsitta monachus). Using bones, whole mount specimens stained for cartilage and bone, and histological sections, we focus on the osteology and morphogenesis of the tarsometatarsus. We also compare the tarsometatarsus development between the altricial monk parakeet with the precocial chicken. The results and conclusions we reached are: (1) the hypotarsus, a character of phylogenetic significance, is monocanaliculate in the adult; (2) digit I retroversion is consequence of the displacement of the articulation site of the metatarsal 1 and its torsion; (3) digit IV retroversion is linked to the development of the trochlea accesoria; (4) in ovo, the ossification and fusion of the metatarsals 2-4 begin in their mid-diaphysis and extends cylindrically to both proximal and distal directions; and (5) the differences in the development of the tarsometatarsus between the monk parakeet and the chicken evidence heterochronies, probably related with their different types of development.

Abundance of insulin-like growth factors 1 and 2, and type 1 insulin-like growth factor receptor in placentas of dogs.

Insulin-like growth factors (IGFs) are among the primary compounds regulating placental development. In bitches, relative abundance of IGF1, IGF2 and IGFR1 mRNA transcripts have been studied in the pre-implantation uterus and early endotheliochorial placentas. The IGF2 and IGFR1 distribution has also been previously described in the uterus before embryo implantation. The aim of this study was to detect, characterize, and localize the presence of IGF1, IGF2, and IGFR1 in early-developing and mature placentas of dogs. Placentas of 15 bitches were analyzed using immunohistochemistry. The IGFs were located in endometrial epithelium and glands, with the staining pattern and intensity being less in mature placentas. Cytotrophoblast cells (CTB) and syncytiotrophoblast (STB) cells contained both IGFs; the labeling was greater in CTB of the early-developing than mature placentas. The maternal endothelium was positively stained for both IGFs, while the vascular endothelium of the chorioallantoic membrane were only stained for IGF2. The IGFR1 was detected in all cell populations evaluated. Results regarding trophoblastic IGF are quite consistent with those reported in human placentas. Spatiotemporal IGFs/IGFR1 pattern might reflect the occurrence of autocrine and paracrine signaling during placentation in bitches, and the involvement in early placental developmental processes. Furthermore, it is hypothesized that, besides hemotrophic actions of plasma IGFs, endometrial secreted IGFs may promote early placental development through histotrophic signaling.

Early and natural embryonic death in Lagostomus maximus: Association with the uterine glands, vasculature, and musculature.

The uterus is an organ with great plasticity due to the morphological and physiological changes it experiences during the estrous cycle and pregnancy. In mammals, pregnancy requires diverse sex hormones, growth factors and cytokines, among others, for promoting uterine remodeling to favor implantation, placentation, and embryo/fetus survival and growth. The hystricognathi rodent Lagostomus maximus (plains viscacha) has a high rate of embryonic resorption. The cranial and middle implants are reabsorbed 25-35 days after intercourse while the caudal embryos continue with their development until two precocial offspring are born. So far, no uterine studies of non-pregnant L. maximus females were performed to determine the possible existence of variations in the organ that could be related to the differential survival of the implants. We used ultrasonography, as well as morphological, morphometric, histochemical, lectinhistochemical, and immunohistochemical methods to study differences in the uterine glands (area), vasculature (area), and musculature (thickness) along the uterine horns in non-pregnant females. Along the uterus, all these structures were in more advanced developmental condition in the caudal region as compared to more anterior positions. These regional variations could be decisive in explaining the reason why only caudal implantations come to term. In contrast, no differences in the in the luminal and glandular epithelial cells, nor in the degree of cell proliferation and apoptosis, and hormonal receptor staining were found. These parameters could be related to implantation along the uterine horns, but not to the differential survival of the implants.

Micromorphology of osteoderms in Dasypodidae (Cingulata, Mammalia): Characterization and 3D-reconstructions.

Osteoderms are present in a variety of extinct and extant vertebrates, but among mammals, the presence of osteoderms is essentially restricted to armadillos (Cingulata, Dasypodidae). Osteoderms have been proposed to exhibit a variety of functionalities in Dasypodidae, mainly protection and thermoregulation, and they have been considered as one of the synapomorphies of this group. In this study, we use high-resolution microcomputed tomography to describe the osteoderm micromorphology of several extant species of Dasypodidae in a comparative context. This study allowed the identification, 3D-reconstruction and volume quantification of different internal structures of osteoderms as well as their interrelations. This detailed characterization of the internal osteoderm morphology was compared in a phylogenetic context to assess the evolutionary trends of the species involved. This enables the identification of distinctive patterns for the most widely recognized clades, the Dasypodinae and Euphractinae with a morphological homogeneity in the microstructure of their osteoderms, in comparison with Tolypeutinae where it has not been possible to establish a common morphological pattern. The most important features for linage differentiation is the degree of compaction of the osteoderms, the number of cavities and the development of hairs. It is likely that the differential development of the various structures occurred as adaptive response to climate changes.

The uropygial gland of the monk parakeet Myiopsitta monachus: Histology, morphogenesis, and evolution within Psittaciformes (Aves).

We describe the morphology, histology, and histochemical characteristics of the uropygial gland (UG) of the monk parakeet Myiopsitta monachus. The UG has a heart-shape external appearance and adenomers extensively branched with a convoluted path, covered by a stratified epithelium formed by different cellular strata and divided into three zones (based on the epithelial height and lumen width), a cylindrical papilla with an internal structure of delicate type and two excretory pores surrounded by a feather tuft. Histochemical and lectin-histochemical techniques performed showed positivity against PAS, AB pH 2.5, AB-PAS, and some lectines, likely related to the granivorous feeding habits. Also, we describe the morphogenesis of the UG of the monk parakeet, which appears at embryological stage 34 as a pair of ectodermal invaginations. Heterochronic events in the onset development of the UG when compared with other birds could be recognized. Finally, to examine the phylogenetic occurrence of the UG within the Psittaciformes and infer its evolutionary history, we mapped its presence/absence over a molecular phylogeny. The reconstruction of the characters states at ancestral nodes revealed that the presence of the UG was the plesiomorphic feature for Psittaciformes and its loss evolved independently more than once.

Lectin histochemical pattern on the normal and cystic ovaries of sows.

The lectin histochemical pattern (LHP) was characterized and compared in normal and cystic ovaries of sows. Six biotinylated lectins (PNA, SBA, WGA, RCA-1, DBA and UEA-1) were used on tissue sections. In the normal ovaries, the reaction to UEA-1 and SBA was mild to moderate in mesothelial and endothelial cells. RCA-1 staining was mild to moderate in theca interna of growing follicles, corpora luteum and mesothelium. In addition, this lectin presented strong reaction in endothelial cells, granulosa cells of atretic follicles, zona pellucida of growing follicles and plasma. DBA showed strong intensity in mesothelial and endothelial cells. There was mild to moderate reactivity to WGA in granulosa cells, corpus luteum and theca interna of follicles in development, and moderate in zona pellucida, in granulosa cells of atretic follicles and mesothelium. PNA staining was mild to moderate in oocytes and in the adventitia and media of medullary arteries. Changes in the LHP of the cystic ovaries were noted; however, there were no differences in these findings between the follicular and luteinized cysts. UEA-1 reactivity in the cystic ovaries was moderately reduced in the mesothelial and endothelial cells, whereas there was mild reduction in the DBA staining in the granulosa cells. Reaction to RCA-1 and WGA in the cysts also was decreased in theca interna, zona pellucida and granulosa cells of atretic follicles. Furthermore, endothelium and theca interna in the cystic ovaries presented mild reduction of marcation to SBA, whereas there was decreased reactivity to PNA in the oocytes and adventitia and media layers of the medullary arteries. The results of the current study show that cysts modify the LHP in swine ovaries. These changes of glycoconjugates in many ovarian structures could modify diverse process and may be one of the reasons for decreased fertility in sows.

Dysregulated expression of the key effectors of the mammalian target of rapamycin signalling pathway in cutaneous papillomas of dogs.

Cutaneous papillomas (CP) are one of the most common skin neoplasms in dogs. Different murine models have shown that persistent activation of the phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway has a central role in the development and progression of CP. The purpose of this study were to evaluate the immunohistochemical expression pattern of two key molecules involved in the PI3K/Akt/mTOR signalling pathway, pAktSer473 , and pS6Ser235/236 , on 36 canine specimens of CP using a tissue microarray. The results show that the PI3K/Akt/mTOR signalling pathway is persistently activated in CP of dogs, pointing to this pathway as a potential therapeutic target.