RESUMO
BACKGROUND: The topographical correlations between certain extracranial and intracranial osseous points of interest (POIs), and their age-related changes, are indispensable to know for a diagnostical or surgical access to intracranial structures; however, they are difficult to assess with conventional devices. MATERIALS AND METHODS: In this pilot study, the 3-dimensional coordinates of extra-/intracranial POIs were determined, thus avoiding perspective distortions that used to be intrinsic problems in 2-dimensional morphometry. The data sets were then analysed by creating virtual triangles. The sizes, shapes, and positions of these triangles described the extent and the directions of the age-related shifts of the POIs. A selection of extracranial and intracranial POIs were marked on half skulls of four warmblood horses in two age groups (young: 6 weeks, n = 2; old: 14 and 17 years, n = 2). The x-, y-, and z-coordinates of these POIs were determined with a measurement arm (FaroArm Fusion, FARO Europe®). Direct distances between the POIs as well as their indirect distances on the x-, y-, and z-axis, and angles were calculated. RESULTS: The analysed virtual triangles revealed that some parts of the skull grew in size, but did not change in shape/relative proportions (proportional type of growth, as displayed by POI A and POI B at the Arcus zygomaticus). The same POIs (A and B) remained in a very stable relationship to their closest intracranial POI at the Basis cranii on the longitudinal axis, however, shifted markedly in the dorso-lateral direction. In contrast, a disproportional growth of other parts of the cranium was, for example, related to POI C at the Crista nuchae, which shifted strongly in the caudal direction with age. A topographically stable reference point (so-called anchor point) at the Basis cranii was difficult to determine. CONCLUSIONS: Two candidates (one at the Synchondrosis intersphenoidalis, another one at the Synchondrosis sphenooccipitalis) were relatively stable in their positions. However, the epicentre of (neuro-)cranial growth could only be pinpointed to an area between them.
Assuntos
Envelhecimento/fisiologia , Imageamento Tridimensional , Crânio/anatomia & histologia , Crânio/fisiologia , Animais , Feminino , Cavalos , MasculinoRESUMO
The cranial and caudal vocal folds (CraF, CauF) of the glottis of adult minipigs (11-27 months; n = 12) were examined after immunohistochemical application of polyclonal anti-von-Willebrand-Factor and anti-Smooth-Muscle-Actin in serial paraffin sections. This examination aimed at a stratigraphical analysis of microvessels; data were compared with findings in humans which had been reported in the literature. (1) The distribution of the microvessels was very heterogeneous in the CraF and in the CauF, but a common pattern existed in both. (2) Characteristic vascular zones and rows were detected; each of them displayed a specific distribution and density of blood capillaries, arterioles, venules, lymphatic capillaries, and lymphatic precollectors. (3) A striking feature was the presence of a subepithelial Avascular Band and of a focal Avascular Area within the lamina propria of the fold's crests. (4) The vascular zones, the rows, the Avascular Band, and the Avascular Area could be allocated to specific layers of the lamina propria: subepithelial, superficial, intermediate, deep layer. (5) The loose Avascular Area at the level of the superficial layer of the lamina propria (in both CraF and CauF) corresponded to Reinke's space in humans in terms of structure and location. (6) The direction/course of blood and lymphatic microvessels shared common features with that of the human vocal fold.
RESUMO
BACKGROUND: This basically anatomical study focuses on two items; firstly, the establishment of a system for the cartographic subdivision of the neopallium; secondly, the topographical correlation of extracranial landmarks and intracranial sites on the neopallium. MATERIALS AND METHODS: The surface of the neopallium was subdivided into 15 sectors with reference to a newly introduced pattern of Primary Sulci. The topographical link between extracranial landmarks and certain intracranial sites (i.e. neopallium sectors) was elaborated by using a simple stereotactic device and a computer-assisted measurement device. Measurements were performed between points on the head's outer surface and on the isolated brain. RESULTS AND CONCLUSIONS: The introduction of an anatomical three-dimensional coordinate system was an essential key issue for this investigation. This setting facilitated the measurements and calculations of the so-called indirect distances that were characterised by their alignment along the three orthogonal axes (x, y, z) of the anatomical coordinate system. The inter-individual comparison (16 adult horses [Equus caballus]) of the indirect distances revealed that each sector centre lay within a distinct morphometric residence area. The measured and calculated data also showed that each sector centre could be assigned to its proper extracranial landmark that - in comparison with other landmarks - was best suited for the optimal allocation of the sector centre point.
Assuntos
Neocórtex , Animais , CavalosRESUMO
OBJECTIVE: In veterinary medicine computed tomography (CT) imaging has gained importance in recent years, especially for diagnostics in pets, but also during the course of experimental studies in animal models for human medicine. In this study the applicability of CT as an imaging method for the depiction of the porcine thorax and in particular of the pig lung was evaluated. MATERIAL AND METHODS: CT examinations were performed with 11 healthy pigs of two age groups. For evaluation, CT findings were related to clinical, radiological, macroscopical, microscopical, and microbiological findings. RESULTS: Clinically relevant anatomical structures were determined and recorded using transverse slices. In ventral recumbency, lung parenchyma density measurements at the levels of the second, fourth and seventh thoracic vertebrae resulted in significantly higher densities of the ventral in comparison to those of the dorsal lung quadrants. CONCLUSION AND CLINICAL RELEVANCE: Computed tomography is a valuable tool for the high-contrast depiction of the porcine lung without superposition. In future studies this CT reference base for unaltered pig lungs may facilitate the identification of anatomical structures within the porcine lung as well as the assessment of pathological lung alterations.
Assuntos
Doenças Pulmonares Intersticiais/veterinária , Pulmão/diagnóstico por imagem , Doenças dos Suínos/diagnóstico por imagem , Suínos/anatomia & histologia , Tomografia Computadorizada por Raios X/veterinária , Animais , Doenças Pulmonares Intersticiais/diagnóstico por imagemRESUMO
BACKGROUND: The extremely complex surface architecture of the equine brain does not allow a uniform transfer of anatomical data from other mammalian species, e.g., dog or cat. Rather, a special approach is required to elucidate the equine-specific patterns of cerebral vascular ramifications. Therefore, a novel cartographic system was applied. Prior attention was paid to the A. cerebri media (MCA) and to the A. corporis callosi (CA), as they spread over the widest part of the neopallium's Facies convexa (i.e. the lateral and dorsal surface), thus being of particular interest in terms of surgical treatment of trauma of the skull and brain. MATERIALS AND METHODS: The brains of 17 adult warmblood horses were studied. The neopallium's Facies convexa was subdivided into 15 sectors clearly delineated by the primary sulci and by related auxiliary lines. The courses and destinations of main branches (= branches of 1st or 2nd order, with a minimum calibre of 0.75 mm) of MCA and CA were topographically analysed by means of superimposed graphical sketches. RESULTS: The MCA had six main branches (numbered in rostrocaudal direction); the CA had seven main branches. The main branches of the MCA spread over the widest part of the Facies convexa, but never reached the rostral pole and the caudal pole of the neopallium. Clearly, the main branches of CA proceeded from the hemisphere's medial side across the Margo dorsalis cerebri, thus supplying rostrodorsal and dorsal sectors of the Facies convexa. CONCLUSIONS: The topographical analysis of the vascular ramification patterns (regions of residence) in combination with the cartographic system of sectors of the neopallium respected the equine-specific surface architecture. It highlighted the distinct vascular supply areas and the particular multiple-supply situations especially in sectors presumably related to the equine area motorica.
Assuntos
Artéria Cerebral Média , Neocórtex , Animais , Encéfalo , Fácies , Cavalos , Artéria Cerebral Média/anatomia & histologia , Neovascularização PatológicaRESUMO
The elimination of specified risk material from food is crucial to restricting the risk to public health arising from bovine spongiform encephalopathy. The distribution of lymphoreticular tissue as potential specified risk material of the bovine lingual tonsil is described in relation to topographical anatomical landmarks. The definition of a proper landmark is a prerequisite for establishing adequate legal regulations concerning the removal of the lingual tonsil after slaughter. The main parameter to identify the lymphoreticular tissue in this study was the immunohistochemical identification of the follicular dendritic cells in the lingual tonsil. Lymph nodules were detected in areas up to 30 mm rostral of a given macroscopic landmark, i.e., the most caudal of the papillae vallatae. This area must therefore be adequately removed from the bovine tongue in the slaughterhouse. The current method for the removal of the lingual tonsil tissue according to Regulation (EC) 999/2001 at the slaughterhouse and alternatives to this method are discussed.
Assuntos
Bovinos/anatomia & histologia , Células Dendríticas Foliculares/citologia , Encefalopatia Espongiforme Bovina/transmissão , Tonsila Palatina/anatomia & histologia , Língua/anatomia & histologia , Matadouros/normas , Animais , Células Dendríticas Foliculares/patologia , Encefalopatia Espongiforme Bovina/prevenção & controle , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Humanos , Imuno-Histoquímica , Linfócitos , Tecido Linfoide/anatomia & histologia , Tecido Linfoide/citologia , Tonsila Palatina/citologia , Tonsila Palatina/patologia , Medição de Risco , Língua/citologia , Língua/patologiaRESUMO
The histological composition of the Lamina propria in pigs - especially in the cranial fold of the glottis - gives reason to expect other phoniatric properties than in man. Age-related changes must be considered.
Assuntos
Prega Vocal/anatomia & histologia , Adolescente , Fatores Etários , Animais , Animais Recém-Nascidos , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Mucosa Laríngea/anatomia & histologia , Fatores Sexuais , Especificidade da Espécie , SuínosRESUMO
The surface architecture of the equine telencephalon is far more complex and complicated than, for example, that of the carnivore's brain, and basic organization patterns are more difficult to recognize. This is due to species differences, to interindividual variations and even to asymmetries between right and left hemispheres. Moreover, a very heterogeneous anatomical terminology, especially in the pioneering older literature, does not allow easy access to a unanimous topographical orientation. This review article presents the key features of this heterogeneity and its anatomical and terminological backgrounds, focusing on the cerebral sulci. The abundant, often divergent data from the reviewed literature are displayed by means of graphical illustrations highlighting the key issues and comparing them with the terminology of the present Nomina Anatomica Veterinaria. These illustrations are supposed to convey the relevant conformities and discrepancies regarding locations, courses and names of cerebral sulci in an easier and more effective manner than written texts could possibly do with such a complex and heterogeneous matter. The data from the selected literature are supplemented by and discussed together with photographs and drawings of brains from our own collection. This combination of a classic review article and own findings is supposed to confirm, to further elaborate and to evaluate the key sulci serving as landmarks for an orientation on the equine neopallium. These are, laterally, the Sulcus suprasylvius, coronalis and praesylvius; dorsally, the Sulcus marginalis; and medially, the Sulcus genualis, cinguli and splenialis. Special attention is also given to the Fissura sylvia; a Fissura sylvia accessoria is proposed.
Assuntos
Cavalos/anatomia & histologia , Neocórtex/anatomia & histologia , Animais , Animais Recém-Nascidos/anatomia & histologia , Feminino , Masculino , Especificidade da EspécieRESUMO
The hypsodont equine cheek tooth erupts continuously throughout life. The collagen fibers of the periodontal ligament (PDL) have to remodel constantly to allow the tooth to move in an occlusal direction. Remodeling of the collagen fiber bundles needs to be well-coordinated in order to maintain functional tooth support. The aim of this study was to examine the role of matrix metalloproteinase-1 (MMP-1) in the collagen remodeling of the equine PDL under physiological conditions. Specimens containing the PDL interposed between the dental cementum and the alveolar bone were taken from nine Warmblood horses at three designated horizontal levels: subgingival, middle, and apical. The expression of MMP-1 was detected immunohistochemically. MMP-1 was found to be present in the specimens of all horses. Immunopositive fibroblasts/fibrocytes were accumulated within individual single collagen fascicles. Our results suggest that MMP-1 induced collagen degradation plays a central role in the physiological remodeling of the equine PDL. The distribution of MMP-1 positive fascicles indicates well-directed remodeling which occurs as an asynchronous process, so that only single collagen fascicles are remodeled at the same time. Due to this remodeling of one fascicle at a time, the overall anchorage of the tooth is preserved at all times.
Assuntos
Bochecha , Cavalos/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Ligamento Periodontal/enzimologia , Dente/enzimologia , Animais , Colágeno/metabolismo , Feminino , Imuno-Histoquímica , MasculinoRESUMO
Fibroblasts and cementoblasts in the periodontal ligament (PDL) of equine cheek teeth were harvested, and monocultures were obtained by means of a "selective detachment" procedure. Cells were characterized by morphological criteria and by immunostaining for vimentin, FVIII, pan-cytokeratin, smooth muscle actin, and pro-collagen. Cementogenic potential of the cells was determined by immunostaining for osteopontin and by histochemical detection of alkaline phosphatase. Equine periodontal fibroblasts (EPF) were spindle-shaped and polygonal. Equine dental cementoblasts (EDC) grew in cobblestone-like clusters. Both EPF and EDC stained positive for vimentin. Only EPF contained smooth muscle actin, pro-collagen, and alkaline phosphatase. Few EDC stained positive for osteopontin. The phenotypes of EPF and EDC and their specific expression of proteins corresponded to PDL fibroblasts and dental cementoblasts of other species. These results indicate the potential use of EPF and EDC in an adequate in vitro model of equine cementogenesis and equine periodontal remodeling.
Assuntos
Cementogênese/fisiologia , Cemento Dentário/citologia , Cavalos/anatomia & histologia , Ligamento Periodontal/citologia , Fosfatase Alcalina/metabolismo , Animais , Técnicas de Cocultura/veterinária , Fibroblastos/citologia , Fibroblastos/enzimologia , Imuno-Histoquímica , Masculino , Ligamento Periodontal/enzimologiaRESUMO
Innate immunity is critically important for the outcome of infection in many diseases. It was previously shown that cathelicidin PR-39, an important porcine multifunctional host defence peptide, is elevated in bronchoalveolar lavage fluid and respiratory tract tissue after experimental infection with Actinobacillus pleuropneumoniae (A.pp.). To date, neutrophil polymorphonuclear leukocytes (PMNs) are thought to be the only source of PR-39. The aim of this study was to further characterize PR-39⺠cells and selected immune cell populations in lung tissue during the peracute (7-10 hours), acute (2 days), reconvalescent (7 days) and chronic (21 days) stages of experimental infection with A.pp. serotype 2. In total, six mock-infected control pigs and 12 infected pigs were examined. Using immunofluorescence double-labeling, antibodies against PR-39 were combined with antibodies against CD3 (T-cells), CD79 (B-cells), Iba1 (activated macrophages), TTF-1 (lung epithelial cells expressing surfactant proteins), macrophage/L1 protein and myeloperoxidase (MPO, cells of the myeloid linage). In the peracute and acute phases of infection, total PR-39⺠cells and myeloid linage cells increased, whereas CD3⺠cells and TTF-1⺠cells decreased. Double labeling revealed that most Macrophage/L1 protein+ cells and to a lesser extent MPO⺠cells co-expressed PR-39. In addition, few bronchial epithelial cells and type 2 alveolar epithelial cells (both identified with TTF-1) produced PR-39. Occasionally, CD3⺠T cells expressing PR-39 were seen in infected animals. Taken together, this study identifies cell types, other than PMNs, in lungs of A.pp.-infected pigs that are capable of producing PR-39. In addition, these findings provide further insights into the dynamics of different immune cell populations during A.pp.-infection.
Assuntos
Infecções por Actinobacillus/metabolismo , Infecções por Actinobacillus/veterinária , Actinobacillus pleuropneumoniae/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Linhagem da Célula , Doenças dos Suínos/metabolismo , Doenças dos Suínos/microbiologia , Infecções por Actinobacillus/microbiologia , Animais , Antígenos de Bactérias/análise , Antígenos de Bactérias/imunologia , Peptídeos Catiônicos Antimicrobianos/análise , Complexo CD3/metabolismo , Antígenos CD79/metabolismo , Células Progenitoras Mieloides/metabolismo , Neutrófilos/metabolismo , Peroxidase/metabolismo , Sus scrofa , Suínos , Linfócitos T/metabolismoRESUMO
The porcine glottis differs from the human glottis in its cranial and caudal vocal folds (CraF, CauF). The fibre apparatus of these folds was studied histomorphometrically in adult minipigs. For object definition and quantification, the colour-selection tools of the Adobe-Photoshop program were used. Another key feature was the subdivision of the cross-sections of the folds into proportional subunits. This allowed a statistical analysis irrespective of differences in thickness of the folds. Both folds had a distinct, dense subepithelial layer equivalent to the basement membrane zone in humans. The subsequent, loose layer was interpreted - in principle - as being equivalent to Reinke's space of the human vocal fold. The next two layers were not clearly separated. Due to this, the concept of a true vocal ligament did not appear applicable to neither CauF nor CraF. Instead, the body-cover model was emphasized by our findings. The missing vocalis muscle in the CraF is substituted by large collagen fibre bundles in a proportional depth corresponding to the position of the muscle of the CauF. The distribution of elastic fibres made the CraF rather than the CauF more similar to the human vocal fold. We suggest that these data are useful for those wishing to use the porcine glottis as a model for studying oscillatory properties during phonation.
Assuntos
Glote/anatomia & histologia , Porco Miniatura/anatomia & histologia , Animais , Colágeno/análise , Tecido Elástico/anatomia & histologia , Feminino , Processamento de Imagem Assistida por Computador , Coloração e Rotulagem/veterinária , Estatísticas não Paramétricas , Suínos , Prega Vocal/anatomia & histologiaRESUMO
Current methods of diagnosis of respiratory diseases in swine are invasive, time-consuming and expensive. Infrared thermography (IRT) of the thorax might provide a new method of high specificity to select swine affected with lung alterations for further diagnostics. In this study, layer thickness of different tissues was determined in frozen thorax slices (FTS) by computed tomography (CT) and then related to skin temperatures measured by IRT in healthy pigs. The aim was to determine appropriate regions of interest (ROI) for evaluation of IRT images. Organ layer thicknesses measured in CT images correspond to those measured in FTS. Temperature differences between lung ROIs and abdomen ROIs were positively correlated with lung layer thickness at certain localizations, and negatively correlated with the thickness of the thorax wall and of inner organ layers. Reference values of differences between skin temperatures were established for two ROIs on the thorax with potential practical use for lung health status determination. Respective ROIs were located on vertical lines crossing the 7th (right) and the 10th (left) thoracic vertebrae. The presence of ribs affected skin temperature significantly.
Assuntos
Pneumopatias/veterinária , Temperatura Cutânea , Doenças dos Suínos/diagnóstico , Suínos/anatomia & histologia , Suínos/fisiologia , Termografia/veterinária , Tórax/anatomia & histologia , Tórax/fisiologia , Abdome/anatomia & histologia , Abdome/fisiologia , Anatomia Transversal , Animais , Raios Infravermelhos , Pulmão/anatomia & histologia , Pulmão/diagnóstico por imagem , Pulmão/fisiologia , Pneumopatias/diagnóstico , Masculino , Radiografia Torácica/veterinária , Valores de Referência , Termografia/métodos , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/veterináriaRESUMO
In the newborn Monodelphis domestica, pituitary and brain are far from their definite shape and structural organization. The presumptive neurohypophysis appears as a mass of proliferating cell immunonegative for neuron-specific enolase (NSE) in the newborn, while perikarya positive for NSE are present in the rostroventral area of the hypothalamus. At the same time, the periventricular areas of the brain, consisting of proliferating cells, are non-reactive for NSE. In the 2.5-day-old specimens of this study, the neurohypophysis displays anti-NSE reactions in the peripheral regions. In animals 8-10 days of age, the amount of reaction product in the neurohypophysis has reached highest levels. This dramatic increase parallels the increase of NSE expression in perikarya of the rostroventral and caudoventral hypothalamus as well as the formation of a band-like reaction zone between the respective hypothalamic areas and the neurohypophysis.
Assuntos
Animais Recém-Nascidos/metabolismo , Sistema Hipotálamo-Hipofisário/crescimento & desenvolvimento , Sistema Hipotálamo-Hipofisário/metabolismo , Gambás/metabolismo , Fosfopiruvato Hidratase/metabolismo , Neuro-Hipófise/metabolismo , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Biomarcadores , Imuno-Histoquímica , Gambás/crescimento & desenvolvimento , Neuro-Hipófise/crescimento & desenvolvimentoRESUMO
Individuals from 18 litters between 0.5 day and 13 days post partum, and two adult specimens of Monodelphis domestica (Marsupialia), were studied by TEM and lectin histochemistry. Positive reactions for PO-lectins in the developing pituitary were found in the vascular and/or perivascular elements; secretory cells did not react. Positive vascular reactions varied with both the type of lectin and the age of the developing animal. In the adults, the reactions were reversed: there were no vascular, but a variety of positive cellular reactions. It is concluded that the adenohypophyseal blood vascular system is very far from being complete and mature in the newborn M. domestica. According to specific data taken from the literature, the lectin histochemistry indicates a sequential appearance of several components of the extracellular matrix, suggesting also that the actively organ-invading capillaries may be a good model for the study of basement membrane development.
Assuntos
Envelhecimento/fisiologia , Endotélio Vascular/ultraestrutura , Gambás/anatomia & histologia , Adeno-Hipófise/irrigação sanguínea , Animais , Animais Recém-Nascidos , Membrana Basal/crescimento & desenvolvimento , Membrana Basal/ultraestrutura , Vasos Sanguíneos/crescimento & desenvolvimento , Vasos Sanguíneos/ultraestrutura , Endotélio Vascular/crescimento & desenvolvimento , Lectinas , Microscopia Eletrônica , Adeno-Hipófise/crescimento & desenvolvimento , Adeno-Hipófise/ultraestruturaRESUMO
The microvascularisation of the equine non-glandular gastric mucosa was investigated using corrosion casts for scanning electron microscopy. Specimens from 11 healthy horses were examined. Corresponding to the high incidence of gastric lesions in the margo plicatus, special attention was paid to the differentiation between the pars nonglandularis and the margo plicatus as a distinct area of the aglandular mucosa. In both areas, the blood vessels of the lamina propria mucosae were arranged in three vascular layers; i. e. I) a basal, II) an intermediate, and III) a subepithelial horizontal level. In the basal (I) and in the intermediate (II) layers the vascular supply was organised in arterial retia-rete arteriosum profundum, rete arteriosum subpapillare- and venous plexus-plexus venosus profundus, plexus venosus subpapillare. Vertical interconnections integrated the layers into the vascular network of the entire lamina propria. The subepithelial (III) layer represented the blood vessels of all the individual connective tissue papillae in the lamina propria mucosae. Ansae capillares intrapapillares were found in the pars nonglandularis. In contrast, each of the papilla of the margo plicatus contained a "cone shaped" rete capillare intrapapillare. The thicker epithelium and lamina propria mucosae of the margo plicatus was therefore supplied by less numerous, but longer intrapapillary blood vessel systems. The typical vascular components of the margo plicatus may be considered to be one of several links in the etiological chain which characterises gastric mucosal lesions in the horse's stomach.
Assuntos
Mucosa Gástrica/irrigação sanguínea , Cavalos/anatomia & histologia , Microcirculação/ultraestrutura , Animais , Arteríolas/ultraestrutura , Capilares/ultraestrutura , Tecido Conjuntivo/ultraestrutura , Feminino , Mucosa Gástrica/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Modelos Estruturais , Valores de Referência , Vênulas/ultraestruturaRESUMO
The course and the arrangement of capsular blood vessels in the joint capsule's wall, together with their extracapsular origins, were investigated using cleared specimens that had been injected with Latex, or Technovit, or India-ink in serum. Arteries enter areas of the joint capsule's wall near its femoral as well as coxal attachment. The intramural vascular network is arranged in layers which are assigned to the stratum fibrosum and stratum synoviale, with one or two intermediate, less distinct layers in between. The ramification in the network of the stratum fibrosum is mainly stellate. Circular anastomoses connecting the supplied areas are located in the capsule's periphery. In the stratum synoviale, the vascular network is made of close, elongated meshes in a circular extension.
Assuntos
Artérias/anatomia & histologia , Cães/anatomia & histologia , Articulação do Quadril/anatomia & histologia , Articulação do Quadril/irrigação sanguínea , Cápsula Articular/anatomia & histologia , Cápsula Articular/irrigação sanguínea , Animais , Aorta Abdominal/anatomia & histologia , LátexRESUMO
The enthesis of the elbow-joint capsule in the dog is described histologically in relation to the specific mechanical forces that operate in different regions along its line of attachment. Special attention is given to the collagen fibre-bone interface in those parts of the capsule that are highly affected by mechanical stress. The histological features of the enthesis are heterogeneous along the entire circumference of the attachment site. Three types of collagen fibre-bone interconnections can be distinguished: (1) periosteal insertion: attachment to the periosteum of the humerus; (2) bony insertion: attachment directly to peripheral osteons; (3) fibrocartilaginous insertion: attachment to the bone via fibrocartilage. The periosteal insertion covers the greatest part of the joint capsule attachment line, along the peripheral borders of the radial and olecranon fossae. In contrast, bony insertions and fibrocartilaginous insertions are focally arranged: bony insertions in the caudoproximal aspect of the olecranon fossa, related to nutrient foramina; fibrocartilaginous insertions in combination with the attachment of distinct ligaments. This distribution reflects a strict relation between the type of enthesis and the biomechanical stress at the attachment site. The periosteal insertion type is predominant in entheses adjacent to pouches of a loose joint capsule -- i.e., regions less dependent on the high tensile strength of collagen fibres. Fibrocartilaginous insertions characterise areas of the joint capsule which are subjected to high biomechanical traction during joint movement. Both structurally and functionally, the entheses of the fibrous layer of the joint capsule are similar to those of tendons and ligaments.
Assuntos
Cães/anatomia & histologia , Membro Anterior/anatomia & histologia , Úmero/anatomia & histologia , Cápsula Articular/citologia , Articulações/anatomia & histologia , Animais , Colágeno/química , Feminino , Humanos , MasculinoRESUMO
Antibodies against human FSH, LH, TSH, ACTH, GH, PRL, and MSH were applied to paraffin sections of newborn (< 1) and pouch-young individuals with the age of 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14 days, respectively (D1, D2,...). In the pouch-young, the antibody reactions occurred only in the pars distalis of the adenohypophysis. The D < 1 individuals included, the reactions were strong for ACTH, moderate/strong for GH, and moderate for MSH. Reactivity for TSH was recorded first in D2 specimens, for LH in D3 animals, for FSH and PRL in D8 animals. There was a remarkable regional distribution of reactive cells within the pars distalis: reactions for ACTH were localized mainly in the rostral area, those for GH were most prominent caudally. The chronological sequence of appearance of the specific hormone-producing cells in the pouch-young generally is in accordance with the characteristic pattern known in other mammalian species. The late onset of differentiation of some cell types indicates the research possibilities that postnatal Monodelphis domestica can offer in the field of ontogenetic studies on the mammalian endocrine system.
Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Gambás/crescimento & desenvolvimento , Adeno-Hipófise/crescimento & desenvolvimento , Hormônios Adeno-Hipofisários/análise , Animais , Biomarcadores/análise , Imuno-Histoquímica , Adeno-Hipófise/químicaRESUMO
On either side of the cloaca of the male Monodelphis domestica, there is a large pack of globular structures lying between the external skin and the ischial arch. The structures within each of these bilateral complexes can be classified into three groups. Group 1 comprises different kinds of glands. There are two large glands, "Paraproctic glands" according to Schaffer (1940), whose spacious cavity is bounded by a secretory epithelium. The secretion is holocrine in a way that cells are shed into the wide cavity. Further, there are two large bodies built of sebaceous acini around a central cavity. The inner surface of the cavity is a squamous stratified epithelium. A peripheral layer of secretory tubuli completes the structure's wall. The bodies are referred to as "Circumanal glands" according to Schaffer (1940). Their excretory ducts end into the cloaca. Group 2 is located between the glands of group 1 and group 3. Macroscopically, the structures of this group are easily mistaken as glands, however, histologically they are identified as a bilateral bulb of the corpus spongiosum, and as a bilateral bulb of the crus of the corpus cavernosum penis. Group 3 includes three different glands that end into a bilateral expansion of the urethra. These accessory genital glands are very distinct due to the histologic characteristics of their secretory epithelium.