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L Mandrioli

Publications and source records attributed to L Mandrioli.

10 recordsLinked to original sources
PubMed2006

Immunohistochemical MHC-II and interleukin 2-R (CD25) expression in lymph nodes of pigs with spontaneous postweaning multisystemic wasting syndrome (PMWS).

Immunohistochemical expression of immunocompetent cells bearing major histocompatibility complex (MHC-II) and interleukin 2-R (IL2-R) (CD25) molecules was performed on lymph nodes with spontaneous postweaning multisystemic wasting syndrome (PMWS). Control lymph nodes displayed intense diffuse immunoreactivity to MHC-II in both follicles and interfollicular areas. A marked reduction of follicular MHC-II immunoreactivity and inconsistent staining of histiocytes in interfollicular areas was observed in PMWS cases with a slight lymphoid depletion; in those cases with moderate to severe lymphoid depletion, there was a progressive decrease in MHC-II expression. In controls and in slightly depleted nodes, IL2-R was equally expressed in interfollicular tissue and in follicles, whereas in moderate and severe cases, it was detected in interfollicular remnants only. Immunohistochemical staining was scored semiquantitatively. The mean MHC-II score was significantly reduced in PMWS cases compared with controls (Spearman test), whereas there was no difference in the IL2-R score. The evident reduction of MHC-II immunoreactivity suggests an impairment in MHC-II linked antigen presenting cell expression.

Animals↗
PubMed2005

Experimental infection of 3-week-old conventional colostrum-fed pigs with porcine circovirus type 2 and porcine parvovirus.

This report describes an experimental infection with porcine circovirus type 2 (PCV2) in combination with porcine parvovirus (PPV) in 3-week-old conventional colostrum-fed pigs with maternal antibodies to both viruses. Two groups of four pigs each were inoculated with PCV2 and PPV. One of the groups received also a commercial inactivated vaccine against porcine pleuropneumonia to evaluate possible effects of the stimulation of the immune system of pigs on the infection. Another group of four pigs was kept as uninfected control. Clinical signs, rectal temperatures and body weights were recorded. Serum antibody titers to PCV2 and PPV were determined at weekly intervals. Pigs were killed 42 days after inoculation and tissue samples were examined for the presence of gross and microscopic lesions. Tissues were also analyzed for the presence of PCV2 and PPV DNA by PCR, and for the presence of PCV2 antigen by immunohistochemistry (IHC). All the pigs had serum antibodies to PCV2 and PPV at the beginning of the trial. None of them developed clinical symptoms or pathological lesions typical of post-weaning multisystemic wasting syndrome (PMWS), a disease associated to PCV2 infection. However, IHC and/or PCR analyses showed that clinically silent PCV2 infection developed in five of the eight inoculated pigs, regardless of the administration of the vaccine. In particular, PCV2 DNA and/or antigen were detected in most of the tissues examined in the two pigs with the lowest titer of maternal PCV2 antibodies at the beginning of the trial. PPV DNA was not detected in any of the samples examined. The five pigs with PCR and/or IHC evidence of PCV2 infection had a mean weight gain during the experiment lower than that of the inoculated PCR-negative pigs considered together and that of the control pigs. In conclusion, it would appear that passive immunity against PCV2 can play a role in preventing the development of PMWS, but is not able to prevent the establishing of clinically silent PCV2 infections. The dissemination and persistence of the virus in the tissues may depend on the level of PCV2 antibodies at the time of inoculation.

Adjuvants, Immunologic↗
PubMed2004

Apoptosis and proliferative activity in lymph node reaction in postweaning multisystemic wasting syndrome (PMWS).

Postweaning multisystemic wasting syndrome (PMWS) affects nursery and growing pigs, and is characterized by wasting, failure to thrive, pale skin, respiratory distress, diarrhoea and sometimes jaundice. Macroscopic findings are aspecific, but lymphocyte depletion in lymphoid tissues is one of the histological hallmarks [Vet. Q. 24 (2002) 109]. Spontaneous cases of PMWS were studied to evaluate proliferative activity and apoptosis as mechanisms involved in the pathogenesis of cell depletion in lymph nodes. The presence of Porcine Circovirus type 2 (PCV2) genome in the processed material was confirmed by in situ hybridization (ISH). The lymph node pattern of depletion was graded as initial, intermediate or final stage according to histological criteria in 10 superficial inguinal nodes from piglets with PMWS which died spontaneously or were slaughtered by euthanasia. The apoptotic and proliferative fraction were investigated by monoclonal antibody MIB1 immunohistochemistry and TUNEL (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-nick end labeling) methods, respectively, and compared to three normal cases. One-way analysis of variance (ANOVA) comparison between the MIB1 index (number of positive cells per 100 nuclei) in controls and PMWS cases revealed a decrease of proliferation in both lymphoid and medulla-like tissues in the initial group (respectively, P=0.0017 and 0.024) but not in the intermediate (respectively, P=0.25 and 0.88) or final (respectively, P=0.47 and 0.81) cohorts. The apoptotic index (number of apoptosis/apoptotic bodies in 100 cells) revealed a statistically significant decrease only in the initial group (one-way ANOVA P=0.05). The proliferation/apoptosis ratio (MIB1/APO ratio) assessed to determine cell turnover disclosed a significant decrease of cell turnover from initial to final PMWS cases (Spearman's rank test: P=0.027). Decreased cell proliferation and not increased apoptosis seems to be the most important variable leading to cell depletion in PMWS lymphoid tissues.

Animals↗
PubMed2003

Bile duct dysplasia and congenital hepatic fibrosis associated with polycystic kidney (Caroli syndrome) in a rat.

Hepatic fibrosis with bile duct ectasia and hyperplasia associated with polycystic kidney disease, analogous to Caroli syndrome in humans, was observed in a rat used as a control in a subchronic toxicity study. Light microscopy of liver sections showed multiple cystic and segmental saccular dilatations and hyperplasia of the intrahepatic bile ducts associated with overgrowth of portal connective tissue; the kidneys had diffuse cystic dilatation of cortical renal tubules. The lesions resembled those of human cases of the fibropolycystic disease termed as Caroli syndrome, which is thought to be the result of a pathologic developmental process known as ductal plate malformation. Recently, an animal model of Caroli syndrome has been described in mutant rats from a colony that constantly showed renal and hepatic cysts and an autosomal recessive mode of inheritance. The finding in our case of identical hepatorenal lesions suggests that the same mutation has occurred incidentally in a standard colony.

Animals↗
PubMed2002

Multiparametric survival analysis of histological stage and proliferative activity in feline mammary carcinomas.

Mammary tumours are among the most frequent malignant neoplasms in the cat and determination of prognosis on histological grounds alone can be unsatisfactory because it does not always correspond to the clinical behaviour of the neoplastic disease. The aim of this two-year post-mastectomy survival study is to relate the histological stage or invasiveness (the most commonly used histological parameter to grade malignancy) to several parameters assessing the proliferative activity-mitotic index, MIB1 index, and AgNOR index. Invasiveness was graded as local and vascular invasion whilst values of the parameters expressing proliferative activity, all quantified by image analysis, have been classified into low and high proliferative activity groups according to their median values, (0.719 for mitotic index, 12.11 for MIB1 index, and 3.19 for AgNOR index). For each group, mean survival (months+/-SD) was calculated. Histological stage (local invasion 21.83+/-7.83 months, blood vessels and/or lymphatics invasion 13.38+/-8.99,P<0.01), mitotic index (low 22.43+/-88.78, high 12.37+/-7.49,P<0.001), and AgNOR index (low 21.86+/-10.68, high 13.82+/-7.11,P<0.05) revealed a significant association with survival in univariate analysis and had an independent prognostic value in multiparametric survival test (P<0.001).

Animals↗
PubMed2002

Sertoli cell tumour with Call-Exner-like bodies in a dog.

An histological diagnosis of Sertoli cell tumour and concurrent seminoma was formulated after complete resection of the right testicle in a 8-year-old Doberman. The unusual histological feature of abundant eosinophilic material with a extracellular location forming the Call-Exner-like bodies is reported.

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

Clinical and pathological findings of acute zinc intoxication in a puppy.

This report describes the clinical and pathological findings in a case of acute zinc poisoning in a young dog. The puppy suffered four days of progressively more severe vomiting and diarrhoea. Jaundice and pale mucous membranes, severe haematemesis and haemoglobinuria were other findings. Despite intensive therapy, the dog died a few hours after hospitalisation. Postmortem examination revealed a metallic foreign body in the stomach, catarrhal gastritis, hepatomegaly and enlarged, dark kidneys. Histology showed hepatic centrilobular vacuolar degeneration, haemoglobinuric nephrosis with early tubular necrosis, haemosiderosis and extramedullary haematopoiesis, as well as neuronal damage. The foreign body was mainly composed of zinc. Plasma zinc values were markedly raised (34.5 microg/ml; normal range 0.8 to 1.0 microg/ml). Pathophysiological mechanisms of zinc poisoning are discussed.

Animals↗
PubMed2001

Immunohistochemical characterisation of the lymph node reaction in pig post-weaning multisystemic wasting syndrome (PMWS).

The superficial inguinal lymph nodes of 10 piglets which had died spontaneously of post-weaning multisystemic wasting syndrome (PMWS), in which the porcine circovirus type II (PCV-II) genome was revealed by PCR, were submitted to immunohistochemical investigation for CD4, CD8, IgM, MAC387, S-100 protein, vimentin and F-VIII-RA and compared with three normal cases. The lymph node reaction was graded as initial, intermediate and end stage according to histological criteria. In the initial and intermediate stages, absence of follicles and depletion of lymphocytes were evident. Associated with this was a reduction in numbers of interfollicular dendritic cells and interdigitating cells and a reduction/absence of B cells and mainly CD4+ T lymphocytes. In the end stage the reduced expression of high endothelial venules and the prevalence of the stromal component of the lymph node was prominent, as well as the above changes. It is concluded that more than one mechanism is involved in the immunosuppressive ability of PCV-II: reduction of the antigen presenting ability and reduction of B cells and CD4+ T cell function.

Animals↗