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P Capelli

Publications and source records attributed to P Capelli.

At least 37 records · Page 2Linked to original sources
PubMed1994

Pancreatic cancer in Europe: Ki-ras gene mutation pattern shows geographical differences.

Seventy-seven pancreatic adenocarcinomas (60 Spanish and 17 Italian) were tested for Ki-ras gene mutations by analysis of polymerase chain reaction amplified sequences. Mutations involving codon 12 (GGT; gly) were detected in 16 Italian and 46 Spanish cases (80.5% in total). All Italian mutations involved the second base and were G to A transitions (GAT; asp) in 8 cases and G to T transversions (GTT; val) in the remaining 8. Forty-two Spanish mutations were characterized. Thirty-eight were at the second and 4 at the first base: asp in 24 cancers, val in 14, arg (CGT) in 2 and cys (TGT) in 2. Previous European studies and our present data show that 149 of the 186 pancreatic cancers harbored a codon 12 Ki-ras mutation (80%), the large majority affecting the second base (73%), with a transitions/transversions ratio of 1.3:1. However, the mutational pattern of cancers of the different European countries shows remarkable differences, both in the site of the mutation (first or second base) and in the ratio of transitions over transversions. Moreover, a significant subgroup of pancreatic carcinomas do not harbor Ki-ras mutations. The classification of pancreatic cancers, according to the presence or absence, and type of Ki-ras mutation, may be of importance in epidemiological studies. A critical reappraisal of existing epidemiological data, through a retrospective genotypic study using paraffin-embedded cancer samples, may reveal significant correlations with specific genotoxic agents.

Adenocarcinoma↗
PubMed1994

Preoperative diagnosis of renal angiomyolipoma: fine needle aspiration cytology and immunocytochemical characterization.

A preoperative diagnosis of renal angiomyolipoma (AML) is of great importance for a correct management of these patients with this tumor. In fact when the lesion is small and asymptomatic a conservative approach may be considered. We have evaluated the radiographic and fine needle aspiration cytology (FNAB) findings in 8 cases of AML. In 3 cases both radiology and cytology were suggestive of carcinoma and thus the patients underwent surgery. In one case both techniques suggested AML but surgery was performed because the lesion was large and symptomatic. In 4 cases where both radiology and cytology suggested AML no surgery was performed. Follow-up data are consistent with the benign nature of the lesions. The immunocytochemical analysis of the FNAB with a panel of antibodies including keratin, vimentin, actin and HMB-45 was indicative of AML in 7 of 8 cases, including 2 of the 3 cases misdiagnosed as carcinomas. The presence of HMB-45-positive perivascular epithelioid cells in the FNABs was the most significant finding. It is concluded that immunocytochemical analysis of FNAB with this monoclonal antibody panel can increase the accuracy of preoperative diagnosis of AML, and allow consideration of a conservative approach in selected cases.

Actins↗
PubMed1994

Clear cell ("sugar") tumor of the lung is a lesion strictly related to angiomyolipoma--the concept of a family of lesions characterized by the presence of the perivascular epithelioid cells (PEC).

We report a comparative study of 3 clear cell tumors of the lung (CCTL) and 3 angiomyolipomas (AML) of the kidney. Morphological analysis shows that the cells of CCTL are identical to the perivascular epithelioid component of AML. Phenotypically they both consistently expressed melanoma-associated antigens recognized by Moabs HMB45 and HMSA-1, while they were negative for HMSA-5. A minority of cells also expressed S-100 protein, vimentin and actin. In addition, one case of CCTL showed mature adipose tissue entrapped in the proliferation, thus suggesting an intermediate form between CCTL and AML. Based on morphological and phenotypical similarities, it is suggested that CCTL and AML belong to the same family of lesions, characterized by the presence of a peculiar muscle cell, expressing different melanoma-associated antigens.

Adult↗
PubMed1994

[Exocrine neoplasms of the pancreas and the Vater's ampulla. Anatomo-clinical and pathogenetic aspects].

Histological, immunohistochemical, and ultrastructural data accumulated in recent years have provided the basis for a more detailed classification of pancreatic cancer. This classification defines new tumour entities with distinct clinicopathologic and prognostic features. Unfortunately, morphologic and phenotypic studies of the more common ductal pancreatic cancer do not provide sufficient information to predict their clinical behaviour. The new field of investigation on genetic abnormalities in pancreatic cancer has not yet provided sufficient data to propose any genetically based classification or prognostic assessment. However, if there is some hope for prevention or cure, this will depend on efforts to clarify the molecular basis of the disease. These features could help in addressing epidemiological studies, in finding markers for diagnosis and prognosis, and might be helpful in devising completely new therapeutic approaches.

Adenocarcinoma↗
PubMed1993

Neoplasia of the ampulla of Vater. Ki-ras and p53 mutations.

Eleven tumors of the ampulla of Vater (5 stage IV and 2 stage II adenocarcinomas, 1 stage II papillary carcinoma, 1 neuroendocrine carcinoma, and 2 adenomas, one with foci of carcinoma) were examined for Ki-ras and p53 gene mutations by single-strand conformation polymorphism analysis and direct sequencing of polymerase chain reaction-amplified DNA fragments. Ki-ras mutations were found in one adenocarcinoma and in the adenoma with foci of carcinoma, both involving mainly the intraduodenal bile duct component of the ampulla. Seven cases showed p53 gene mutations: four advanced-stage adenocarcinomas, the papillary carcinoma, the neuroendocrine carcinoma, and the adenoma with foci of carcinoma. Nuclear accumulation of p53 protein was immunohistochemically detected in the morphologically high-grade areas of the five cancers harboring a p53 gene missense point mutation. The adenomas, the two frame shift-mutated cancers, and the adenomatous and low-grade cancer areas of mutated carcinomas were immunohistochemically negative. Our data suggest that in ampullary neoplasia 1) p53 mutations are common abnormalities associated with the transformation of adenomas and low-grade cancers into morphologically high-grade carcinomas, and 2) Ki-ras mutations are relatively less frequent and might be restricted to tumors originating from the bile duct component of the ampulla.

Aged↗
PubMed1993

Pancreatic adenocarcinomas frequently show p53 gene mutations.

Thirty-four pancreatic adenocarcinomas were studied for the presence of p53 gene mutations by the single-strand conformation polymorphism method and by direct sequencing of PCR-amplified fragments. p53 protein expression was immunohistochemically evaluated using monoclonal PAb1801 and polyclonal CM1 antibodies. Mutations were detected in 14 cases. The transitions were six G to A and two A to G; the transversions were one C to G and two A to C; the remaining three were frameshift mutations. Immunostaining results were identical with both antibodies. Nuclear immunohistochemical p53-positive cells were found in nine p53 mutated cases and in 12 cases in which no mutation was detected. In most of these latter cases only a minority of cancer cells showed immunohistochemical positivity. Twenty-nine cases, including all p53 mutated cancers, were known to contain codon 12 Ki-ras gene mutations. Also in the light of the demonstrated cooperation of ras and p53 gene alterations in the transformation of cultured cells, our data suggest that p53 mutation is one of the genetic defects that may have a role in the pathogenesis of a proportion of pancreatic cancers.

Adenocarcinoma↗
PubMed1991

Evidence of c-myc gene abnormalities in mediastinal large B-cell lymphoma of young adult age.

Six cases of mediastinal large B-cell lymphoma (MLCL) with sclerosis were analyzed for the presence and patterns of c-myc and bcl-2 loci rearrangements, and for the presence of Epstein-Barr virus DNA sequences by Southern blot hybridization, c-myc gene alterations were found in three of six cases. Two cases showed the presence of mutations or small rearrangements at the 3' end of the first exon. The c-myc gene abnormalities found in these two cases are similar to those observed in the translocation 8;14 of the endemic Burkitt's lymphomas or in its variants t(2;8) and t(8;22). A third case showed a major rearrangement of c-myc gene, with truncation within its first intron, similar to those observed in sporadic Burkitt's and in acquired immunodeficiency-associated lymphomas. None of the cases displayed bcl-2 gene rearrangements or contained viral sequences. Our data suggest a possible role for a translocation-mediated c-myc activation in the pathogenesis of MLCL. Conversely, bcl-2 gene and Epstein-Barr virus do not appear to be involved in the pathogenesis of these peculiar lymphomas. The association between c-myc structural modifications and MLCL also seems to be of relevance in light of the peculiar tendency of this tumor to involve unusual extranodal site (eg, kidney), reminiscent of the spreading attitude of Burkitt's limphomas.

Adult↗
PubMed1990

Expression and gene rearrangement of the T-cell receptor in human thymomas.

Human thymomas are epithelial neoplasms frequently associated with an exuberant lymphoid component. This mixture of epithelial cells and lymphocytes closely mimicks the organization of normal thymic cortex. However, it is not known whether thymocytes in thymoma express the T-cell receptor (TCR) for the antigen. We have analyzed the molecular configuration of TCR genes and their phenotypic expression in eight thymomas. In all we detected polyclonal rearrangements of TCR genes and cytoplasmic expression of TCR molecules in most thymocytes, thus indicating that rearranged TCR genes in thymomas are functioning genes. In addition, these findings suggest that the epithelial component of thymomas, even if neoplastic, is still capable of directing thymocyte differentiation.

Adolescent↗
PubMed1989

Evidence of pulmonary tropism of bamifylline and its main active metabolite.

The extent of the extraplasmatic tropism of bamifylline (Bamifix) was evaluated in the rat and in man by assaying concentrations of bamifylline and of its main active metabolite AC-119 in lung tissue and plasma. After a single oral and intravenous administration of bamifylline in the rat, the ratio between pulmonary and plasma concentrations was between 2.0 and 3.2 for bamifylline, and between 4 and 15 for AC-119 during the observation period considered. On the other hand, the same ratios, calculated after the oral and intravenous administration of theophylline, ranged between 0.20 and 0.39. In studies on man, samples of plasma and lung tissue were obtained during surgery in subjects affected by pulmonary neoplasia and previously subjected to therapy with bamifylline according to the usual dosage scheme. The ratios between tissue and plasma concentrations, at the steady-state and in conditions of equilibrium between the compartments, were 9.4 for bamifylline and 34.7 for its active metabolite. The particular tissue tropism of bamifylline, that appears to be due to its high lipophilic character, could partly explain its high therapeutic index.

Animals↗
PubMed1988

Distribution of melanoma specific antibody (HMB-45) in benign and malignant melanocytic tumours. An immunohistochemical study on paraffin sections.

The distribution of a recently produced melanoma specific antibody (HMB-45) has been evaluated histochemically on paraffin sections in a large panel of melanocytic and non melanocytic tumours. Results have been compared with the presence of S-100 protein. HMB-45 was shown to be a highly specific antibody being present only in melanomas, junctional melanocytes and histogenetically related neoplasms such as melanocytic neuroectodermal tumour of infancy and, at low levels, on a proportion of peripheral nerve sheath tumours. The high specificity of HMB-45 antibody, coupled with the greater sensitivity of S-100, makes the combined use of these markers practical in the differential diagnosis of skin tumours and of metastatic lesions of uncertain primary site.

Antibodies, Neoplasm↗
PubMed1988

Increased sensitivity to protein kinase C activation in aortas of spontaneously hypertensive rats.

The aortic muscle of spontaneously hypertensive (SHR) and normotensive control (WKY) rats was stimulated with phorbol esters and the contractile response was measured as isometric tension. Phorbol esters are known activators of protein kinase C. The aortas of SHR were characterized by the following distinct alterations in the response to phorbol myristate acetate: (1) increased sensitivity: half-maximal force was achieved at 62 +/- 6 nmol/l phorbol myristate acetate in SHR and 105 +/- 8 nmol/l in WKY; (2) increased contractility: the maximal force developed by phorbol myristate acetate was greater in SHR aortas (1.9 +/- 0.3 versus 1.6 +/- 0.2 g in WKY) compared with the decreased contractility generated with noradrenaline and high levels of potassium; (3) decreased dependency on extracellular calcium for half-maximal tension: in the presence of 3 mumol/l phorbol myristate acetate 50% of maximal force was attained at 21 +/- 8 mumol/l extracellular calcium compared with 49 +/- 9 mumol/l in WKY; (4) diminished relaxation in response to excess extracellular calcium: phorbol myristate acetate-precontracted WKY aortas began to relax when calcium was raised above 4 mmol/l in the bath and relaxation reached 51% at 8-10 mmol/l. Relaxation was almost absent in SHR (3-7%). Hence, there is an abnormality in the response to protein kinase C activation by phorbol esters in SHR vascular smooth muscle. Intracellular calcium appears to be involved. Studies of protein kinase C will prove important in understanding vascular smooth muscle function in normal and abnormal states.

Animals↗
PubMed1988

Immunohistochemical analysis of sarcoid granulomas. Evaluation of Ki67+ and interleukin-1+ cells.

Proliferating cells have been immunophenotypically characterized in lymph node and bronchoalveolar lavage (BAL) samples obtained from patients with active and inactive sarcoidosis with the cell-cycle-related antigen Ki67. Ki67 monoclonal antibody was used by combined immunohistochemical methods together with antibodies recognizing macrophage- and T-cell-subset-related antigens using avidin-biotin peroxidase (ABC) and alkaline phosphatase-anti-alkaline phosphatase (APAAP) systems. Many proliferating Ki67+ cells were found in affected mediastinal lymph nodes. These cells were mainly located around granulomas and exhibited phenotypical markers of helper/inducer T cells (CD3+, CD4+). Ki67+ macrophages could not be detected in the same lesions with this technique. A different picture was found in BAL preparations where proportions of both T lymphocytes and macrophages were Ki67+. The presence of replicating lymphocytes could be correlated to disease activity, whereas the proportions of Ki67+ macrophages did not show significant differences between active and inactive disease. Interleukin-1 (IL-1) expression was investigated in the same samples with a specific antiserum. Epithelioid macrophages in granulomas and BAL macrophages in all cases exhibited cytoplasmic staining revealing an activated status. Interestingly, giant cells in granulomas were mainly devoid of IL-1 immunoreactivity. These studies support the concept that activated cells at different sites of ongoing inflammation play a central role in the mechanisms accounting for granuloma formation.

Adult↗
PubMed1985

[Our experience with the diagnostic and prognostic unreliability of pre- and postoperative CEA in human breast cancer].

The carcinoembryonic antigen (CEA) levels were determined in 42 breast cancer patients at I, II, III, IV stages of TNM classification. Plasmatic preoperative CEA levels was under 6 ng/ml in the 94% of patients. The postoperative CEA levels of six patients who developed metastases during the follow-up was elevated in five cases, but the elevation never preceded the clinical and radiological diagnosis of metastases.

Breast Neoplasms↗
PubMed1983

Endocrine-metabolic effects of l-carnitine in patients on regular dialysis treatment.

Twenty-three patients on regular dialysis treatment (RDT) were given 1-carnitine orally or in dialysate for six months. All patients remained in a stable biochemical state; hyperlipidaemia was reduced with an increase in HDL-cholesterol. Hormonal pattern was unmodified. Serum and muscle carnitine and acetylcarnitine constantly increased. L-carnitine in RDT, by restoring tissue reserves, improves metabolic alterations without any side-effects.

Acetylcarnitine↗
PubMed1977

HLA B27 and ankylosing spondylitis: a population and family study in Sardinia.

Thirty-eight patients with ankylosing spondylitis (AS) and 494 unrelated controls in Sardinia were HLA Typed. HLA B27 was present in 81.8 per cent of AS vs 5.3 per cent of controls (relative risk: 80). Twenty-six apparently healthy B27 positive individuals were studied clinically and radiologically, and six (23.0 per cent) presented signs of definite or suspicious AS. A family study on relatives of seven AS B27-positive and four AS B27-negative patients was also made. The results suggest a dominant heredity of AS susceptibility, and are compatible with a direct involvement of the B27 antigen in the mechanism of AS, but we cannot rule out a closely linked disease-susceptibility gene with incomplete penetrance.

Adult↗