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J Martin de las Mulas

Publications and source records attributed to J Martin de las Mulas.

16 recordsLinked to original sources
PubMed2003

Oncogene HER-2 in canine mammary gland carcinomas: an immunohistochemical and chromogenic in situ hybridization study.

Immunohistochemical (IHC) HER-2/neu protein overexpression was found in 17.6% of canine mammary gland carcinomas, a percentage similar to that observed in human breast carcinoma, but there was no gene amplification by chromogenic in situ hybridization (CISH). Canine mammary carcinoma would be a suitable natural model of that subset of human breast carcinomas with HER-2 protein overexpression without gene amplification.

Animals↗
PubMed1997

Development of microscopic lesions in splenic cords of pigs infected with African swine fever virus.

Acute forms of African swine fever are characterized by hemorrhagic lesions in the lymphoid organs. This paper reports the evolution of lesions in the splenic cords of pigs inoculated with African swine fever (ASF) virus (strain Malawi'83). Ultrastructural examination of the splenic cords of the infected pigs revealed numerous macrophages attached to the muscle cells harboring virus replication center and cytopathic effects at 3 dpi (days post-infection). From 5 dpi, the splenic cords contained a large number of erythrocytes associated with abundant fibrin deposits, mainly arranged around the muscle cells, from which macrophages had disappeared. It is likely that the ASF virus replication, and consequent cytopathic effects, observed in the fixed macrophages of splenic cords, may be responsible for the fibrin deposition.

African Swine Fever↗
PubMed1996

A monoclonal antibody to ruminant fibrinogen produced through immunization with ovine peripheral blood leukocytes.

By immunizing BALB/c mice with peripheral blood leukocytes (PBL) we have obtained a monoclonal antibody (MAb) named Co.1C9D10, specific for the gamma chain of ruminant fibrinogen. This MAb immunoprecipitates a molecule of apparent molecular weight of 55/65 kDa under reducing conditions and of around 300 kDa under nonreducing conditions. Co.1C9D10 recognized the gamma chain of fibrinogen by immunoblotting techniques and blood vessel plasma from paraffin embedded tissues by immunocytological techniques. Flow cytometry analysis showed that fibrinogen appears adhered to monocytes and granulocytes being eliminated through EDTA treatment of the cells. This phenomenon explains why PBL used as immunogen was able to induce an MAb against fibrinogen.

Animals↗
PubMed1996

Immunohistochemical characterization of hemangiopericytomas and other spindle cell tumors in the dog.

The immunohistochemical expression of muscle actin has been studied in 45 canine hemangiopericytomas (CHP) using a monoclonal antibody (HHF35) and formalin-fixed, paraffin-embedded specimens. The distribution of vimentin, desmin, cytokeratins, lysozyme, factor VIII-related antigen, S-100 protein, and glial fibrillary acidic protein was studied both in CHP and in some canine soft-tissue neoplasms (seven fibrosarcomas, seven benign schwannomas, seven benign fibrous histiocytomas, and six leiomyosarcomas) used as controls for differential diagnosis. All CHP and control tumors expressed vimentin. Twenty-three CHP expressed muscle actin, whereas all control tumors analyzed were muscle actin-negative, with the exception of leiomyosarcomas. Among muscle actin- and vimentin-positive CHP, one case could be reclassified as leiomyosarcoma because it was desmin-positive, two cases expressed lysozyme, and nine cases expressed S-100 protein. Among muscle actin-negative and vimentin-positive CHP, seven expressed S-100 protein. In addition, S-100 protein was detected in five schwannomas. All CHP and control tumors analyzed were negative for cytokeratins, factor VIII-related antigen, and glial fibrillary acidic protein. Our results support the hypothesis of a pericytic origin of CHP, and suggest that muscle actin, desmin, vimentin, and lysozyme could be useful for the differential diagnosis of canine spindle cell tumors, but not all these neoplasms can be identified with these tumor tissue markers.

Actins↗
PubMed1995

Description of a new population of fixed macrophages in the splenic cords of pigs.

The ultrastructure of porcine splenic cords was analysed by light and electron microscopy after both perfusion and immersion fixation. The external aspect of the splenic cords was found to be composed of a network of smooth muscle cells arranged between the trabeculae and the venous sinus walls. Macrophages frequently attached to smooth muscle cells surrounded the whole of their surfaces and were attached by slender cytoplasmic projections. Intercellular junctions in the form of electron-dense areas 200-350 nm in length and 45-55 nm in thickness were observed in the macrophage membrane close to the muscle cells. In the splenic cords of nonperfused animals, in addition to the macrophage population adhering to smooth muscle cells, numerous macrophages without cell junctions were also seen and identified as free macrophages.

Actins↗
PubMed1993

Rhabdomyosarcomas in young pigs in a swine breeding farm: a morphologic and immunohistochemical study.

Within a 6-month-period, solitary or multiple tumors were observed in 25 young pigs in their first weeks of life in a swine breeding farm. The herd comprised approximately 100 animals, and affected pigs were observed in several litters. The number of affected littermates varied from one to three. Five animals, all from different litters and with a total of 11 tumors, were studied. Histologically the tumors were classified as undifferentiated sarcomas. Electron microscopic examination of the tumors (n = 3) revealed myogenic differentiation, characterized by the presence of numerous cytoplasmic filaments with longitudinal densities and cytoplasmic dense bodies. Immunohistochemically, all 11 tumors were labeled by vimentin and desmin antibodies. Two tumors from which frozen material was available were additionally labeled by a titin antibody but did not show immunoreactivity with antibodies directed against myosin and alpha-sarcomeric actin. The tumors were finally diagnosed as undifferentiated rhabdomyosarcomas. The high incidence of these tumors within a short period of time in multiple young animals in different litters indicates a common causative event. The clinical history suggests a genetic cause.

Animals↗
PubMed1992

Epithelioid sarcoma in a dog.

A tumour in an 11-year-old male crossbred Fox Terrier, showing the clinical and pathological features of epithelioid sarcoma in man is reported. Clinical aspects, location, peculiar pattern of spread and evolution, together with histopathological and immunohistological findings of this rare tumour simulating a granuloma are described. Controversial histogenesis is discussed.

Animals↗
PubMed1992

Localization of African swine fever viral antigen, swine IgM, IgG and C1q in lung and liver tissues of experimentally infected pigs.

An immunohistological study was carried out on lungs and livers of pigs experimentally infected with two different African swine fever virus (ASFV) isolates. ASFV antigen, swine immunoglobulins (IgM and IgG) and (Clq) complement were demonstrated in both organs at different stages of infection. The ASFV antigen was mainly found in mononuclear phagocytic system (MPS) cells. Immunoglobulins and complement were observed in plasma, infected and non-infected phagocytic cells and cell debris. These findings suggest the presence, in acute infection, of immune complexes which may be involved in immunopathogenic mechanisms.

African Swine Fever↗
PubMed1991

Caprine peripheral neuroblastomas: structural and ultrastructural features, intermediate filaments profile and neuro-endocrine characterization.

In this report the morphological and immunohistochemical features with respect to intermediate filament proteins and the neuroendocrine nature of bilateral neuroblastomas possibly originating from the adrenal medulla in a goat kid are presented. Histologically, the tumours were composed of small, round, blue cells organized in highly cellular nests and sheets separated by fibrovascular septa. Isolated cells mimicking the morphological features of neurones were observed in both tumours. Ultrastructurally, dense-core neurosecretory granules, about 100 nm in diameter, and irregularly organized neurotubular networks were seen. The small tumour cells were only labelled by vimentin, while the neurone-like cells were labelled by both neurone-specific enolase and synaptophysin. The lack of staining of the tumour cells by the neurofilament proteins antiserum, which was also observed in a human neuroblastoma (used as positive control) has been previously reported and is probably the result of the tissue processing and/or the poor differentiation stage of the tumours. The vimentin labelling of tumour cells could be explained by the poor differentiation stage of the tumours, since vimentin is the only intermediate filament protein in presumptive neuroblasts, being replaced by neurofilament proteins in later stages of neurogenesis.

Animals↗
PubMed1991

Pulmonary intravascular macrophages in rabbits experimentally infected with rabbit haemorrhagic disease.

Attention has already been drawn to the presence of pulmonary intravascular macrophages (PIMs) in species in which the lung plays an important part in the removal of particles from the bloodstream. The stimulation of PIMs under certain conditions has been related to pulmonary oedema and congestion. In order to ascertain whether these cells are found in rabbits, healthy animals were inoculated with a liver homogenate obtained from animals which had died of rabbit haemorrhagic disease, a condition characterized by vascular phenomena and pulmonary oedema. PIMs were detected both in experimental and healthy control animals. They shared the morphological characteristics reported for other species, particularly with respect to the presence of intercellular junctions with endothelial cells. In experimental animals, PIMs were actively involved in the removal of cell debris which may or may not have been associated with the presence of rabbit haemorrhagic disease virus antigen.

Animals↗
PubMed1991

Immunohistological diagnosis of rabbit haemorrhagic disease in experimentally infected rabbits in Spain.

The immunoreactivity of routinely processed liver and lung tissue samples obtained from rabbits inoculated with tissue explants from naturally infected animals when antisera directed against parvovirus from different species (canine, feline and porcine) as well as a RHD virus antiserum were employed has been tested by different immunoperoxidase methods. Cross-reactivity between RHD-virus antigens and parvovirus antigens was present. Best results were obtained with RHD and canine parvovirus antisera with the ABC method. The immunoreactivity in the liver was found in hepatocytes, Kupffer and bile duct cells. In the lung, it was exclusively observed in intravascular macrophages.

Animals↗
PubMed1991

Intracystic carcinoma of the breast. A clinicopathologic entity.

Two intracystic breast carcinomas with papillary pattern, one of which was argyrophilic, are reported, and their peculiar clinical features emphasized. The confusing terminology used in literature is also discussed. The fainly well-defined clinico-pathological features of these tumors allow them to be classed as a specific clinico-pathological variety of ductal breast carcinoma. The immunohistochemical study, which was negative to ALA, ACTH, GH, PRL and NSE, led us to consider the potential mucoid nature of the argyrophilic granules.

Aged↗
PubMed1990

Pulmonary intravascular macrophages in lungs of pigs inoculated with African swine fever virus of differing virulence.

The role of pulmonary intravascular macrophages (PIM) in a viral infection has been studied by structural and ultrastructural methods with two strains of the African swine fever (ASF) virus: the virulent strain E70 and the attenuated strain E75. Pulmonary intravascular macrophages were the cells of the mononuclear phagocyte system of the lung most involved in the replication of strain E70, showing a marked cytopathic effect and necrosis. Concurrently, their size and number increased sharply. This stimulation of PIMs by the virulent strain of the ASF virus, together with the cytopathic effect, might be the cause of the abundant masses of cell debris found in septal capillaries and thus be related to the pulmonary oedema that characterizes the acute forms of the disease. With the attenuated strain of the ASF virus, stimulation of PIMs, as well as viral replication within them, was also intense, but the cytopathic effect was less. Later, in the course of the infection, the number of PIMs decreased sharply and then alveolar macrophages increased, bearing most of the viral replication and signalling the onset of a pneumonic process.

African Swine Fever↗
PubMed1990

Immunohistochemical demonstration of Mycoplasma gallinarum and Mycoplasma gallinaceum in naturally infected hen oviducts.

Using indirect immunoperoxidase (IIP), peroxidase anti-peroxidase (PAP) and avidin biotin-peroxidase complex (ABC) immunohistochemical methods, Mycoplasma gallinarum and M gallinaceum antigens were demonstrated in ethanol-fixed paraffin-embedded oviduct sections from hens the eggs from which showed suboptimal hatchability. Specific immunoperoxidase staining was detected at the mucosa in the magnum portion of the oviduct. Optimal staining was achieved by applying the ABC method, though both IIP and PAP methods can also be used for diagnosis. Isolation and identification techniques gave similar results for the species of avian mycoplasmas involved.

Animals↗
PubMedDate not supplied

Pathological and immunohistochemical study of the abomasum and abomasal lymph nodes in goats experimentally infected with Haemonchus contortus.

Histopathological changes and the distributions of T and B lymphocytes and IgG producing plasma cells were recorded in the abomasum and abomasal lymph nodes of goats 3, 7 and 21 weeks post-infection (wpi) after an experimental infection with H. contortus. The low rate of worm recovery by 3 wpi (5.6%) might have been due to larvae death as suggested by the presence of granulomas in the abomasal mucosa at 3 and 7 wpi, or simply due to a poor larval establishment. Marked increase in the secretion of mucus by mucous cells together with an abundant infiltration of eosinophils, mast cells, CD3+ T lymphocytes, CD79a+ B cells, IgG+ plasma cells and globule leukocytes were recorded in the abomasal mucosa, especially at 7 wpi. Except for the globule leukocytes, this reaction decreased substantially by week 21, suggesting this cell type may have been involved in rejection of adult nematodes. The abomasal lymph nodes showed marked hyperplasia, particularly of CD79a+ B cells and IgG+ plasma cells in all infected goats. These reactions may have been responsible for the reduction in the number of worms found in the abomasum between 3 and 7 wpi.

Abomasum↗