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A Poletti

Publications and source records attributed to A Poletti.

137 records · Page 8Linked to original sources
PubMedDate not supplied

Enzyme and immunohistochemistry of follicular hyperplasia in AIDS-related lymphadenopathy.

We used a panel of monoclonal and polyclonal antibodies to analyze frozen and paraffin-embedded lymph node biopsy specimens from 25 intravenous drug abusers (IVDA) with acquired immunodeficiency syndrome (AIDS)-related lymphadenopathy histologically characterized by follicular hyperplasia. Our aim was to obtain diagnostic clues to this commonly occurring pattern. Double-labelling immunohistological studies were also performed on selected frozen sections and 13 plastic-embedded specimens were tested by a number of enzyme reactions. Consistent features in IVDA included abnormally high numbers of intrafollicular T-cells, positive for acid phosphatase and beta-glucuronidase, most of which had Leu-2a-positive phenotype; a marked reduction or loss of mantle zone B-cells (positive for surface IgD-IgM and alkaline phosphatase); and disarray of the network of follicular dendritic reticulum cells (DRCs), as revealed with DRC-1 and anti-S-100 protein antibodies or with reaction for 5'-nucleotidase. When present, distinctive intrafollicular clusters of Leu-2a-positive T-cells and mantle zone B-cells were nearly always associated with areas lacking DRCs in some patients. The intrafollicular hypervascularity invariably found in IVDA proved to be of a true capillary nature, as demonstrated by alkaline phosphatase, 5'-nucleotidase, and ATPase reactions. In control tissues, all showing absence of Leu-2a-positive intrafollicular T-cells, most of the above individual changes could be detected, although they were occasional, mild, and never associated within the same follicle. By contrast, combined immunohistological and enzyme histochemical findings in IVDA indicated that in most follicles such changes were marked and very often associated within the same follicle in each case.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Complex↗
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S-100 protein detection in "follicular macrophages" of mouse lymphoid organs by ABC immunoperoxidase method.

The distribution of S-100 protein was investigated in normal or reactive lymphoid organs from adult mice, rats and humans by the avidin-biotin complex ABC) immunoperoxidase method. In mouse lymph nodes and spleen the protein appeared to be confined to the "tingible-body macrophages" and occasionally in sinus histiocytes in the lymph nodes. No immunoreaction product was detected in the other cell types present inside or outside the follicles. In the thymus the immunostained cells were located in the medullary area and corresponded morphologically to mononuclear PAS-positive cells with histiocytic appearance. By contrast, in rat and human organs S-100 protein was detected in interdigitating reticulum cells and dendritic reticulum cells. The present findings indicate that S-100 protein is located differently in mouse lymphoid organs and in other mammalian species.

Animals↗
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Ki-67 and c-jun expression in pancreatic cancer: a prognostic marker?

The proto-oncogene c-jun is involved in cell proliferation and Ki-67 antigen permits determination of the proportion of proliferating tumour cells. The expression of c-jun and Ki-67 in pancreatic cancer and their relation with tumour histological features and patients survival were evaluated. Specimens were obtained as follows: 14 pancreatic cancer from patients radically operated, 8 liver metastases from subjects submitted to palliation, 5 normal pancreas from organs donors and 5 chronic pancreatitis. Ki-67 and c-jun were studied by immunohistochemistry. The percentage of tumour cells stained for c-jun was increased in 11/14 cases. A high c-jun expression was more frequently found in liver metastases than in pancreatic cancer tissue (p=0.031). The frequency of high c-jun expression was more elevated in short-term as compared to long-term survivors (Fisher's exact test, p=0.031 and log-rank, p=0.03). The percentage of tumour positive cells for Ki-67 showed a mean value of 12.8% in primary pancreatic cancer and was lower than in the liver metastases (32.5%) (p=0.029). Significantly lower values were found in long-term (6.5%) as compared to the short-term survivors (18.1%) (p=0.032 and log-rank, p=0.006). A positive relation was demonstrated with stage (p<0.05), lymph node state (p=0.045) and perineural invasion (p=0.0001). In the multivariate analysis the Ki-67 staining was the most important determinant of long-term survival (p=0.005). c-jun and Ki-67 are overexpressed in pancreatic carcinoma, but only Ki-67 is a strong predictive factor.

Aged↗
PubMedDate not supplied

The expression of proto-oncogene c-jun in human pancreatic cancer.

The proto-oncogene c-jun is involved in cellular proliferation by interfering with signals that lead to cellular differentiation. Moreover the induction of metalloproteinase gene appears to utilise the c-jun oncogene as intracellular messenger. The aims of this study were to evaluate a) the expression of c-jun oncogene in pancreatic cancer b) its relation with tumor histological features. Surgical specimens of pancreatic cancer were collected from 22 patients radically operated upon, and from 11 submitted to palliation. As a control group, 5 specimens of normal pancreas and 5 specimens of chronic pancreatitis were studied. C-jun staining was graded as follows: (-) positive cells < 10%, (+) from 10 to 30%, (+2), from 30 to 60%, (+3) from 60 to 90%. Glucagon and somatostatin staining was graded counting the positive cells of total numer of Langherans islet cells counted. c-Jun expression (low: < 30% and high: > 30%) was related to stage, architectural and cytological grading, vascular, lymph nodal, perineural invasion. Normal pancreas and chronic pancreatitis tissues appear to express the c-jun protein in less than 10% of ductal cells. The percentage of tumor cells stained for c-jun is increased as compared to the control group in 28/33 cases: in 13 (46%) it ranges from 10 to 30%; in 10 (36%) from 30 to 60% and in 5 (18%) from 60 to 90%. The frequency of high or low c-jun expression is not different in relation to the histological features of tumor. Moreover, c-jun protein is present in 40% of cells of Langherans islets in normal pancreas, chronic pancreatitis and pancreatic cancer. The Langherans islet cells stained for c-jun exhibit also a positivity for glucagon. In conclusion; a) in pancreatic cancer, the expression of c-jun is increased in tumour cells in majority of cases as compared to the control group, b) a c-jun positivity is also found in alpha cells with a pattern not different from control group, but the relation between the alpha cells and c-jun production is unknown, c) c-jun expression does not vary in relation to histological findings.

Adult↗
PubMedDate not supplied

Discriminant analysis of WAIS results in different types of dementia and depressed patients.

A Multivariate Analysis of Covariance and Discriminant Analysis were carried out on complete WAIS profiles obtained from three groups of demented patients: Multi-Infarct Dementia patients, Senile Dementia of Alzheimer Type patients, and Alcoholic Dementia patients. A group of middle-aged Depressed patients was also included. WAIS did not differentiate among dementias, but Picture Completion and Block Design subtests proved to be effective in differentiating dementia from depression.

Aged↗
PubMedDate not supplied

[Diagnostic and therapeutic problems in brucellosis uveitis (author's transl)].

The diagnosis of ocular brucellosis relies on the Witmer's ratio between ocular and seric specific antibodies. If the dosage in acqueous humor is not available a presumptive diagnosis is given by significative values of serologic tests (buffered antigene test, indirect immunofluorescence, passive hemagglutination test) and by the cell-immunity test (TIL and IML). Treatment must be local, symptomatic and general, with antibiotherapy associated with desensibilization.

Anti-Bacterial Agents↗