Biomedical subjects

L Della Salda

Publications and source records attributed to L Della Salda.

At least 19 recordsLinked to original sources

PubMed2006

Immunohistochemical characterization of Kisselev nodules (ectopic lymphoid follicles) in wild boar (Sus scrofa L.).

This paper describes the histopathological features and cellular distribution of T lymphocytes (CD3), B cells (CD79), follicular dendritic cells (FDC) and macrophages (alpha-1-antitrypsin, lysozyme) in lymphoid aggregates (Kisselev nodules) found in the lung, kidney and liver of wild boar (Sus scrofa L.). The distribution of immunoreactive cells, tested for antibodies, was similar to that found in the cortex of lymph nodes: lymphoid follicles with germinal centers mainly consisting of CD79+ B cells with sparse interfollicular tissue (CD3+ T lymphocytes). This finding and the association of these structures with helminthic infections suggests that local humoral immunity is central to the organism's response to parasitic challenge. The presence of follicular dendritic cells confirms the high degree of organization of these lymphoid-like structures. The role of other pathogenic factors and the induction of chronic inflammatory reaction in these ectopic lymphoid sites is also discussed.

Animals↗

PubMed2006

Placental abnormalities in ovine somatic cell clones at term: a light and electron microscopic investigation.

To investigate the reasons for fetal losses after somatic cell nuclear transfer, an immunohistochemical and ultrastructural analysis of cloned placentae was performed. The main features observed were a marked reduction of villous vascularization, hypoplasia of trophoblastic epithelium, lack of binucleate cells, immaturity of placental vessels and reduced vasculogenesis. By means of transmission electron microscopy (TEM), a diffuse thickening and lamination of subtrophoblastic basement membrane (SBM) were noted in cloned placentae. These results led us to hypothesize, through an autoamplification model, that the abnormal vascularization, the ischaemia and the low development of an high specialized trophoblastic epithelium were the primary causes of the fetal loss occurring after somatic cells nuclear transfer.

Animals↗

PubMed2005

Spontaneous ocular squamous cell carcinoma in twin goats: pathological and biomolecular studies.

Ocular squamous cell carcinoma (OSCC) is a well-characterized tumour occurring spontaneously in cattle and other mammalian species but not previously reported in the goat. This report describes the histological features of well-differentiated OSCCs in twin goats. Biomolecular investigations led to the identification of Papillomavirus-related DNA sequences within the neoplastic ocular parenchyma of both animals, but immunohistochemical and ultrastructural studies failed to demonstrate viral particles. A putative role of Papillomavirus in the aetiology of OSCC is discussed, together with other possible causative factors.

Animals↗

PubMed2005

Benign giant cell tumour of tendon sheaths in a European Lynx (Lynx lynx).

The histological, histochemical, immunohistochemical and ultrastructural features of a benign giant cell tumour (BGCT) of tendon sheaths in a 12-year-old male European lynx (Lynx lynx) are reported herein. The neoplastic mass involved the subcutaneous and inter-muscular tissues of the first, second, third and fourth digit of the left forelimb, from the phalanxes up to the carpus. The tumour appeared as a grey-whitish tissue mottled with darker areas, along with several scattered foci of orange colour. Histologically, the lesion consisted of a mixed population of numerous, multinucleated giant cells and epithelioid or spindle-shaped mononuclear cells embedded in a loose, highly vascular stroma. Neoplastic cells lined cleft formations and synovial-like projections into cystic spaces. No osteoid matrix could be detected. Haemorrhage and necrosis were also observed. The mononuclear and the giant cells were tartrate-resistant acid phosphatase and periodic acid-Schiff positive, being also immunohistochemically reactive for lysozyme and vimentin, with a few cells showing immunopositivity also for alpha-1-antitrypsin. Ultrastructurally, histiocyte-like cells, fibroblast-like cells and multinucleated giant cells were observed, but no virus-like particles could be detected in any of the above cell types. The BGCT of tendon sheaths, a fairly uncommon neoplasm in animals, has not been previously reported in the lynx.

Animals↗

PubMed2004

Heat shock proteins (HSPs) 27, 72 and 73 in normal and pre-ulcerative mucosa of the gastric pars oesophagea in swine.

Heat shock proteins (HSPs), known to play a key role in cellular homeostasis, may also play a role in the defensive mechanisms of gastric mucosa. By means of appropriate immunohistochemical and immunobiochemical techniques, the expression of HSP27, HSP72 and HSP73 within the epithelium of normal and pre-ulcerative (hyperkeratinized) mucosa of the pars oesophagea of abattoir pigs was assessed. In normal mucosa, HSP72 and HSP73 expression was mainly limited to the basal epithelial cell layer, whereas HSP27 expression was consistently detected within the superficial epithelial cell layers. In hyperkeratinized mucosa, HSP72 and HSP73 immunoreactivity appeared to be more widespread, becoming very intense within epithelial cells affected by hydropic degeneration. Hyperkeratinized mucosa also showed HSP27 immunoreactivity, which was particularly intense in epithelial areas affected by hydropic degeneration. Western blot analysis confirmed HSP27, HSP72 and HSP73 expression in normal and in pre-ulcerative mucosa of the pars oesophagea. Semi-quantitative analysis showed that for all three HSPs the immunoreactivity was more intense in pre-ulcerative mucosa than in normal mucosa. The different expression patterns observed may have functional significance; further studies are needed, however, to define the role of HSPs in swine oesophagogastric lesions, the aetiology and pathogenesis of which are largely unknown.

Animals↗

PubMed2003

Hypertrophy of intestinal smooth muscle in cats.

Pathological findings of four cats with severe and diffuse smooth muscle hypertrophy of the small intestine (MHSI) are reported and compared to those of five cats with segmental MHSI secondary to neoplastic obstruction and four controls. Histology demonstrated a constant association between idiopathic MHSI and submucosal fibrosis and chronic lymphoplasmacytic enteritis. Morphometry (gut diameter, thickness and area of muscular layers, number and density of smooth muscle nuclei) and MIB-1-immunolabelling showed that the thickness increase was mostly due to hypertrophy, but hyperplasia was also evident. Microbiology from ileal content samples was performed in two cats with primary MHSI, and Campylobacter spp. were isolated, which were also demonstrated by immunohistochemistry and ultrastructure. The association of chronic enteritis with idiopathic MHSI suggests that factors released in intestinal inflammation may also act as hypertrophy stimuli for smooth muscle cells.

Animals↗

PubMed2002

Central nervous system cryptococcoma in a cat.

This report describes the gross, histopathological, immunohistochemical and electron microscopic findings in a 4-year-old cat with systemic Cryptococcus neoformans infection. A 1-cm diameter pontine mass, pinpoint lesions in the cerebellum and in the right kidney were the main macroscopic findings. A presumptive diagnosis of cerebral neoplasia with metastasis was formulated. Light microscopy revealed a huge number of yeasts surrounded by a pyogranulomatous inflammatory reaction in the cerebral parenchyma and, to a lesser extent, in the kidney, while the meninges were not involved. The positive mucicarmine stain that coloured the capsule of the yeasts was indicative of cryptococcal infection. Immunohistochemistry confirmed the presence of C. neoformans var. grubii (C. neoformans serotype A). Electron microscopy revealed yeasts with a massive fibrillar capsule and lamellar cell wall free in the cerebral tissue and within macrophages.

Animals↗

PubMed2002

Cell proliferation patterns in canine infundibular keratinizing acanthoma and well differentiated squamous cell carcinoma of the skin.

The aim of the present study was to investigate if the evaluation of cell proliferation of the well differentiated squamous cell carcinoma (WDSCC) and infundibular keratinizing acanthoma (IKA) could be useful in the differential diagnosis between these two tumours. Eighteen IKAs and ten WDSCCs were selected for this study. Two different methods were used to assess the activity of cell proliferation: MIB1 immunohistochemical detection and AgNOR proteins silver staining. The quantification of proliferative parameters was performed by means of an image analyzer and expressed as MIB1 index and AgNOR area (MNORA). Both MIBI immunohistochemical and AgNOR histochemical patterns were different in WDSCC and IKA; moreover analysis of variance showed a significant difference for both parameters employed (MIB1 index, MNORA) between WDSCC and IKA (P<0.003 for MIB1 index; P<0.0001 for AgNOR area). The results show that canine WDSCC and IKA have a different proliferative behaviour and the assessment of cell proliferation can be considered as a useful adjunctive tool to the histopathological investigation in the differential diagnosis of these tumours.

Animals↗

PubMed1999

Protein degradation and apoptotic death in lymphocytes during Fiv infection: activation of the ubiquitin-proteasome proteolytic system.

The movement of a cell through the sequential phases of apoptosis is accompanied by a progressive decrease in cell size with loss in protein mass. In lymphocytes from Hiv-infected persons, protein loss during apoptosis is due to increased protein degradation rather than decreased synthesis. To identify and characterize the proteolytic enzymes or enzyme systems involved in this process, we studied several features of protein turnover in lymphocytes from peripheral blood and lymph nodes during the natural and experimental infection by feline immunodeficiency virus (Fiv). This animal model allowed us to integrate in vivo results with in vitro observations of protein damage. Here we report that protein breakdown in apoptotic cells is concomitant with the activation of the ATP and ubiquitin-dependent multicatalytic system (proteasome). We suggest that proteasome activation is part of the proteolytic cascade in the execution phases of apoptosis in AIDS.

Animals↗

PubMed1999

Evaluating mitotic activity in canine and feline solid tumors: standardizing the parameter.

Three different methods for evaluating mitotic activity (mitotic count, mitoses/area, mitotic index) were applied to different types of canine and feline solid tumors to determine the method that is most objective and correlates best with other parameters of cell proliferation. Mitotic activity was evaluated on toluidine blue stained histological sections. Slides stained with histochemical (AgNOR proteins) and immunohistochemical (MIB1, PCNA) markers of cell proliferation were available for each case. Quantitation of mitotic activity and cell proliferation parameters was performed with an image analyzer. Mitotic activity assessment was compared with cell proliferation indices and its ability to discriminate tumors grouped on histologically based criteria including the histological type, malignant or benign characteristics, and grade. A significant correlation by linear regression analysis with other parameters assessing cell proliferation revealed that mitotic index correlated 1000% and mitoses/area and mitotic count correlated 40% of the time. In discriminating the proliferative activity of tumors grouped by histological criteria, mitotic index and mitotic count revealed 1000% concordance with the other parameters of cell proliferation, while mitoses/areas showed 80% concordance.

Animals↗

PubMed1998

Apoptotic fraction in lymphoid tissue of FIV-infected SPF cats.

In the present study the apoptotic fraction has been investigated in peripheral blood mononuclear cells (PBMCs) and in lymphoid tissue of six clinically asymptomatic serologically positive specific pathogen free (SPF) FIV-infected cats with a decline in peripheral blood CD4+ lymphocytes, compared to five FIV- SPF controls. Apoptosis in PBMCs was scored in relation to cell cycle phases judged by the integrating cytometric measure of DNA content with 3H-thymidine and 3H-leucine incorporation. Apoptosis in lymphoid tissue was revealed with the ApopTag-peroxidase kit, quantified by image analysis and expressed as apoptotic index (number of apoptosis per 100 cells). The high percentage of apoptotic death in lymphocytes from FIV+ cats was chronologically related to the entrance of cells in the S phase of the cell cycle (p < 0.0001). No difference in the apoptotic index was revealed comparing the follicular, cortical + paracortical and medullary compartments in lymph nodes of FIV+ and FIV- cats. In each group of cats a similar pattern of apoptosis expression was revealed in lymph nodes: significantly higher in follicular vs. both cortical + paracortical and medullary compartments (p < 0.001). In the thymus a significant increase in apoptotic index was revealed in the cortical compartment of the FIV+ cats compared to FIV- (p < 0.001), while in the spleen both the red and white pulp expressed a higher value in FIV+ cats compared to FIV-(p < 0.05) and the former showed a pattern of expression as follows: in the red pulp significantly higher than in the white pulp (p < 0.001). This investigation suggests that the priming signals for apoptosis in FIV infection parallels the S phase of the cell cycle and peripheral blood changes could follow both thymic and splenic modifications in apoptotic expression.

Animals↗

PubMed1998

Pretelangiectasis and telangiectasis of the bovine liver: a morphological, immunohistochemical and ultrastructural study.

Forty-five livers from conventionally slaughtered Holstein-Friesian steers with telangiectasis were studied by histochemical methods, immunolabelling for fibronectin, laminin and type IV collagen, and transmission electron microscopy. None of the previously described changes in telangiectasis (necrosis, hepatitis, thromboembolism, dilatation of the space of Disse by glycogen extruded from hepatocytes and reduced density of the perisinusoidal reticulin framework) were evident. Pretelangiectasis (sinusoidal dilatation) and telangiectasis (blood-filled cavities) were characterized by sinusoidal barrier alterations, leading to sinusoidal capillarization; and there was progressive formation of a true basement membrane and perisinusoidal fibrosis. Comparison of bovine liver telangiectasis and human peliosis hepatis suggests that they have a similar pathogenesis. It is suggested that a primary alteration of the sinusoidal barrier is responsible for an increased deposition of basement membrane components (fibronectin, laminin, type IV collagen) in the perisinusoidal region, and fibrosis. These are likely to render the exchange of oxygen and substrates between blood and hepatocytes more difficult and to produce haemodynamic imbalances, leading to hepatocyte atrophy and eventually to sinusoidal disruption.

Animals↗

PubMed1997

Superficial and deep defects in dyschondroplastic and degenerated pig articular cartilage.

Normal and pathological (osteochondrotic and osteoarthrotic) pig articular cartilages from medial humeral and femoral condyles were studied by scanning electron microscopy. The pathological cartilages showed primitive osteochondrotic lesions with progressive aspects according to the severity of the pathology (flaking, fibrillation and cracks) and other superficial changes (micro-undulation, micro-fissurations, clefts) that appeared to be a consequence of the action of intense mechanical stresses such as shearing forces, compressive deformation, friction of the articular surfaces. The observation of deep lesions such as cracks and fractures at or near the interface between cartilage and calcified zone, frequently observed both at medial condyle and at intercondylar crista of the humerus, often evolving in cartilagineous flaps, were related to excessive tangential and shear forces induced by an abnormal articular topography resulting in joint instability. This pathological joint dynamic could be also worsened by an anomalous leg conformation (cross-legs) and/or by an increased occurrence of environmental micro- and macrotrauma (impact loading). Also in this case, the frequency and severity of the lesions can be increased if the deep layer is affected by osteo-chondrotic lesions. The results stress the pathogenetic importance of mechanical load in initiating and worsening the articular lesions in pigs; they also suggest that the resulting alterations can be influenced by a pre-existing different maturity or pathological condition of the cartilage.

Animals↗

PubMed1996

Blood and serous cysts in the atrioventricular valves of the bovine heart.

A survey of 30,907 slaughterhouse cattle (5,984 calves, 15,937 young adult, 8,986 cows) was carried out to determine the incidence of blood and serous cysts on atrioventricular valves. The cysts were classified by their content (blood/serous fluid), location (mitral/tricuspid valve), and size. Cyst wall samples were processed for histology, immunohistochemistry for factor VIII-related antigen, and transmission electron microscopy. The content of some cysts was studied by electrophoresis and biochemical and microbiologic methods. Older cows had a higher incidence (16.2%) than younger animals (11.5% in calves, 7.9% in steers, 6.4% in heifers), suggesting that the lesions may be acquired. Blood cysts were often present on both atrioventricular valves; serous cysts prevailed on the mitral valve. Cysts of both types were larger in older animals; serous cysts were larger than the blood cysts. Histologically, blood cysts contained fresh blood, and serous cysts were filled with a hyaline fluid devoid of cells, sterile, and biochemically similar to lymph. All the cysts were lined with endothelium, but a positive immunostaining for the factor VIII-related antigen was appreciable only in blood cysts. Ultrastructurally, the endothelium was composed of flat endothelial cells holding several cytoplasmic filaments, lying in blood cysts on a continuous and often laminated basal lamina with many cytoplasmic projections. The results support the hypothesis that cysts of the atrioventricular valves derive from the dilation of blood and lymphatic valvular vessels, do not regress with age, and are mainly the result of mechanical effects.

Aging↗

PubMed1995

Quantification of nucleolar organiser regions in canine perianal gland tumours.

The proliferative activity in 28 canine perianal gland tumours was examined by the quantitative evaluation of the nucleolar organiser regions associated with argyrophil proteins (AgNORs). These regions were stained with a specific silver stain and quantified directly by light microscopy and by computerised image analysis. The relationships between some of the parameters used (the number of AgNORs per nucleus, the area of AgNORs per nucleus and the ratio of the area of AgNORs to the area of the nucleus) were also examined in relation to the histopathological grades of the tumours. All the parameters showed a high correspondence with the tumours' proliferative activity, and the ratio of the area of AgNORs to the area of the nucleus was the most significantly correlated with the tumours' histological patterns.

Adenocarcinoma↗

PubMed1995

Adaptive cellular response to osmotic stress in pig articular chondrocytes.

The authors studied the effects of a wide range of medium osmolarities (from 0.28 osM (physiological osmolarity of plasma and synovial fluid) to 0.58 osM) by altering Na+ concentration in high density cultures of pig articular chondrocytes in order to analyze the behaviour of some functional and structural parameters during cell adaptation to these imposed changes in the ionic environment. Biochemical and morphological results indicated that, even if isolated from the tissue matrix and cultured in vitro, chondrocytes maintained active osmoregulation systems which are present in living conditions. They showed a similar biochemical and morphological behavior when cultured at 0.28 osM and 0.38 osM but they were able, with regard to protein synthesis, aminoacid transport and proliferation rates, to respond quickly and to adapt to 0.48 osM medium as well. On the contrary, the treatment at the highest osmolarity (0.58 osM) early altered these biochemical parameters and was detrimental or even gave rise to lethal damage during long-term treatment. Furthermore, while chondrocytes cultured in 0.28-0.38 osM medium maintained phenotypic characteristics in culture, the higher osmolarities (0.48-0.58 osM) caused morphological changes in cell populations resulting in loss of phenotypic cell stability as demonstrated by their taking on a fibroblast-like shape as well as a lack of ability to assembly matrix proteoglycans.

Adaptation, Physiological↗

PubMed1994

Dystrophy-like myopathy in a foal.

Two muscle biopsies from the gluteus medius and semitendinosus muscles of a six-month-old male standardbred trotter with clinical signs of hypertrophy and hypertonicity, and an electromyogram showing myotonic discharges in the glutei, semitendinosus and semimembranosus muscles, were examined by histological, histochemical and ultrastructural methods. Histologically, the main findings were variations in fibre size and shape, vacuolisation, hyalinisation and the splitting of fibres, an increase in the numbers of internal nuclei, infiltration by connective tissue and fat, hypertrophy and the predominance of type I fibres, and clusters of one type of fibre. These histological results resembled those in human muscular dystrophy.

Age Factors↗

PubMed1993

Giant cells in anaplastic mammary carcinoma of the dog and cat.

Four uncommon anaplastic mammary carcinomas containing numerous giant cells are described in three dogs and one cat. The giant cells of all cases were studied by means of monoclonal and polyclonal antibodies to detect epithelial (carcinoembryonic antigen and keratin) and mesenchymal (vimentin, lysozyme and S-100 protein) differentiation. Most of them proved to have an epithelial immunophenotype. Ultrastructurally, scattered bundles of tonofilaments but no lysosome-like bodies could be detected. One tumour had an additional, different type of giant cell, which had a benign multinucleated osteoclast-like appearance, gave positive staining for acid phosphatase, had a histiocytic-stromal immunohistochemical pattern, and was, ultrastructurally, multinucleate with irregular folds and no evidence of tonofilaments. In one case some giant cells had an epithelial immunophenotype and others a stromal immunophenotype, even though their histological and ultrastructural features were the same. In the least histologically differentiated tumour the giant cells presented a coexpression of intermediate filaments. This supported the theory that there might be a stem cell origin for most canine mammary tumours.

Animals↗