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P Grigolato

Publications and source records attributed to P Grigolato.

At least 19 recordsLinked to original sources
PubMed2001

p53 is dispensable for apoptosis but controls neurogenesis of mouse dentate gyrus cells following gamma-irradiation.

Mammalian cells respond to DNA insults by activating cell-cycle checkpoints. This may result in a temporary cell growth arrest which allows DNA repair before proliferation or induces apoptosis. p53 is one of the main contributors in regulating these activities. To get a better insight on the molecular mechanism underlying these activities we studied the role of p53 in apoptosis and neurogenesis of brain cells from adult p53(+/+) or p53(-/-) mice exposed to gamma-irradiation. Apoptosis and neurogenesis were assessed up to 14 days following the injury. Five-ten hours following gamma-irradiation, cells with TUNEL positive nuclei were identified within the subgranular zone of dentate gyrus (DG) of both p53(+/+) and p53(-/-) mice. At the same time-points, pyknotic and shrinking nuclei were visualized by Hoechst 33258 staining. Furthermore, gamma-irradiation increased the number of proliferating cell nuclear antigen (PCNA) positive cells with a peak at 5-10 h in both animal groups. PCNA immunoreactivity was detected in cells exhibiting condensed nuclei as visualized by Hoechst 33258 staining. Neurogenesis, assessed by mitotic marker p34(cdc2) immunoreactivity, showed a biphasic response to gamma-irradiation both in p53(+/+) and p53(-/-) mice which was characterized by an early inhibition and a delayed stimulation. In p53(-/-) mice, the time required by DG granule cells to recover from the lesion and to stimulate proliferation was significantly shortened in comparison with wild-type mice thus resulting in an accelerated neurogenesis. Our data indicate that following gamma-radiation p53 plays a role in regulating cell-cycle progression rate but it is dispensable for promoting apoptosis of DG granule cells.

Animals↗
PubMed2001

High resolution allelotype of nonfunctional pancreatic endocrine tumors: identification of two molecular subgroups with clinical implications.

A high resolution allelotype for nonfunctional pancreatic endocrine tumors (NF-PETs) has been generated by microsatellite analysis of DNA from 16 frozen cases, each probed with 394 markers. Two subgroups of NF-PETs were found. Seven cases showed frequent, large allelic deletions [loss of heterozygosity (LOH)] with an average fractional allelic loss (FAL) of 0.55, whereas nine cases showed a small number of random losses with a FAL of 0.15. Designated high or low FAL, respectively, these genetic phenotypes showed correlation with the ploidy status: high-FAL tumors were aneuploid, low-FAL were diploid. Chromosomes 6q and 11q showed LOH in >60% of cases. About 50% of cases had losses on 11p, 20q, and 21. Selected LOH analysis on an additional 16 paraffin-embedded NF-PETs confirmed the high frequency of 6q and 11q LOH. The allelotype of NF-PET is markedly different from that of either ductal or acinar tumors of the pancreas as well as from that of functional-PETs. Moreover, whereas deletions involving chromosome 11 also are a feature of functional-PETs, the involvement of chromosome 6q is characteristic of NF-PETs. Survival analysis showed that none of the single chromosomal alterations was associated with outcome, whereas ploidy status is an independent factor adding prognostic information to that furnished by the proliferative index measured by Ki-67 immunohistochemistry.

Adenoma, Islet Cell↗
PubMed2001

Rectal localization of metastatic lobular breast cancer: report of a case.

The incidence of extrahepatic gastrointestinal metastases from breast cancer is reported in the literature only as necroscopy studies (6-18 percent); they usually originate from lobular or a mixed ductal-lobular subtype. Nonspecific presenting symptoms, death of the patients caused by other more frequent metastases, and variable radiographic features mimicking primary neoplasms cause a clinical underestimation of this pathology. We report here a case of rectal metastasis from a lobular carcinoma eight years after mastectomy.

Biopsy↗
PubMed1999

The spleen in the Wiskott-Aldrich syndrome: histopathologic abnormalities of the white pulp correlate with the clinical phenotype of the disease.

The Wiskott-Aldrich syndrome (WAS) is a X-linked hematologic disorder characterized by thrombocytopenia, eczema, and immunodeficiency of variable severity. Reported here are the results of a morphologic, morphometric, and immunophenotypic analysis of splenic lymphoid tissue in 12 WAS patients with documented molecular defect and with different disease severity. Spleens from 29 age-matched patients with different diseases were used as controls. Paraffin-embedded tissue (from all cases) and fresh-frozen samples (from 5 WAS patients and 4 control subjects) were used to study the different white pulp compartments by classic morphologic, immunophenotyping, and image analysis techniques. Data were statistically analyzed by both parametric and nonparametric tests. Spleens from WAS patients showed a significant depletion of the total white pulp (p = 0.0008), T cell (p < 0.05), and B cell (p = 0.0002) areas and marginal zone (MZ) thickness (p < 0.0001). Among WAS patients, a negative correlation was found between the score of severity of the disease and all variables considered (Spearman's rank correlation coefficient, r = -0.79, r = -0.73, r = -0.68, and r = -0.56, respectively). In conclusion, this study shows that in WAS a general depletion of the splenic white pulp occurs, supporting the evidence that WAS is characterized by a combined immune defect. The significant reduction of the MZ may explain the inability of WAS patients to mount a response to T-independent antigens.

Antigens, CD↗
PubMed1998

HLA class I antigen and transporter associated with antigen processing (TAP1 and TAP2) down-regulation in high-grade primary breast carcinoma lesions.

Five specimens of normal mammary tissue and 53 primary breast carcinoma lesions were tested for expression of HLA antigens and components of the antigen-processing machinery by immunohistochemical staining. The expression of transporter associated with antigen processing (TAP) 1, TAP2, and HLA class I antigens in breast carcinoma lesions was significantly associated with tumor grading. Like normal mammary tissue, the 16 low-grade (G1) breast carcinoma lesions showed strong staining for TAP1, TAP2, and HLA class I antigens. In contrast, only 12 (32%) of 37 high-grade (G2 and G3) breast carcinoma lesions displayed the normal staining pattern. In 14 (38%) of 37 high-grade lesions, HLA class I antigen down-regulation was observed without loss of low molecular mass polypeptide and/or TAP staining. Congruent down-regulation of HLA class I antigen and TAP1 or TAP2 was found in 8 (22%) of 37 high-grade lesions. Complete loss of HLA class I antigens, TAP1, and TAP2 was observed in 3 (8%) of 37 high-grade lesions. No lesion was negative for TAP1 and/or TAP2 staining while positive for HLA class I antigen staining. These data demonstrate an association of HLA class I antigen and TAP down-regulation with tumor progression in breast carcinoma. This association suggests that loss of HLA and/or TAP may represent an escape from the host's immune pressure or may reflect the accumulation of abnormalities associated with neoplastic progression. This accumulation of defects in antigen processing and presentation may in turn be responsible for reduced recognition of malignant cells by putative clinically relevant tumor-specific T cells.

ATP-Binding Cassette Transporters↗
PubMed1994

Cytometric ploidy and proliferative activity in colorectal carcinoma.

Thirty cases of colorectal carcinoma have been evaluated for proliferative activity with the monoclonal antibody Ki 67 and with flow cytometry for ploidy, DNA index and the S-phase fraction. In the series, 30% of tumours were strictly aneuploid, 23.8% tetraploid and 45% diploid: "non diploid" cases accounted for 53.8%. The mean comprehensive values of DNA index, percent S-phase and Ki 67 positive fraction were 1.4%, 11.5% and 50%, respectively. The parameters considered showed no statistically significant correlation with each other or with the common histo-pathologic parameters, such as grading and staging. The prevalent prognostic importance of ploidy compared to DNA index is emphasized, and particular attention is paid to diploid cases with a high growth fraction (S-phase fraction), which could make up an "at risk" category. Therefore, we attempted to identify subsets, within groups of the same histologic stage, with a different evolutive significance in relation to DNA content, percentage of positivity to Ki 67, S-phase fraction and ploidy. With such a multi-parametric approach, particular groups of patients at risk could be defined, which are perhaps more sensitive to specific support therapies.

Adenocarcinoma↗
PubMed1992

Suppurative granulomatous lymphadenitis. Immunohistochemical evidence for a B-cell-associated granuloma.

The cellular composition of suppurative granulomas was investigated by the application of monoclonal and polyclonal antibodies to paraffin sections and compared with nonsuppurative, hypersensitivity-type granulomas. Macrophages, T cells, and dendritic cells showed a similar distribution in both types of granulomas. In addition to the presence of granulocytes, a major difference between suppurative granulomas and hypersensitive-type granulomas concerned their relationship with B lymphocytes. Hypersensitive-type granulomas were surrounded by small mantle B cells, but they did not contain any B lymphocytes. In contrast, variable numbers of B cells were found either at the periphery or in the center of suppurative granulomas. In view of their morphology (medium size, pale cytoplasm, irregular nuclear shape) and phenotype (L26 +/LN1 -/MB2 +/MT2 +) these B lymphocytes closely resembled monocytoid B cells. The monocytoid B cells might have a role in the recruitment of polymorphonuclear granulocytes and in the development of the necrosis, which occur within suppurative granulomas.

Acid Phosphatase↗
PubMed1991

Static cytometry of DNA in breast lump with reference to grading.

Fresh smears of 400 consecutive cases of breast lumps stained with Feulgen stain were measured with densitometric technique in static cytometry. A correlation was observed between DNA content expressed by the DNA index and histologic grading of malignant lesions; relatively high values were observed in the group of "hyperplasias", which were similar to G1. Values of DNA content in different categories: benign, hyperplastic (nodular and sclerosing adenosis, epitheliosis . . .) and all malignant types variously graded in G1, G2 and G3, show broad areas of overlapping, suggesting that the parameter is not always discriminating between benign, hyperplastic and malignant, but it can identify different amounts of DNA (high and low degrees) within a homogeneous category. Correlation between number of hypertetraploid nuclei (4c) and histologic grading was also evident. Therefore, fresh smears, in relation to DNA content and to the percentage of hypertetraploid elements allow a better definition of "high and low degree" lesions in a short time with possible prognostic involvement as regards tumoral progression.

Breast Neoplasms↗
PubMed1989

Histological features of uteroplacental vessels in normal and hypertensive patients in relation to birthweight.

Placental bed biopsies were obtained during caesarean section from normal, pre-eclamptic and hypertensive pregnancies. Of the 14 biopsies from normal pregnancies 13 showed normal vascular physiological changes in the decidua and in the myometrium. Biopsies from 24 pregnancies complicated by pre-eclampsia showed acute atherosis in 18 and physiological changes limited to the decidua in six; none had normal physiological changes. Biopsies from five hypertensive patients showed all three types of histological changes. The mean birthweight centile was lower in the group with atherosis than in the group with limited and the group with normal physiological changes.

Birth Weight↗
PubMed1987

Blue nevus of the endocervix. A study of five cases.

The pathologic and immunohistochemical features of 5 cases of blue nevus of the endocervix are presented: 4 of them were studied ultrastructurally. The lesions were incidentaly discovered at microscopic examination and showed pigmented dendritic cells in the cervical stroma. Immunocytochemical examination showed all cases to be positive for S-100 protein. Ultrastructurally they contained melanosomes, were surrounded by a basement membrane, and displayed occasional desmosome-like devices. Histogenesis is discussed, and support for a schwannian origin is presented.

Cystadenoma↗
PubMed1987

Ultrastructural renal findings in allografted kidneys of patients treated with ciclosporin A.

22 renal biopsies of 22 patients with 6-month-old transplants have been examined at the light- and electron-microscopic level to demonstrate the toxic effects induced by ciclosporin A (CS). These patients presented stable renal function and were exempt from acute rejection symptoms or nephrotoxicity. Interstitial fibrosis, tubular atrophy and interstitial lymphocytic infiltration were the lesions most often observed by light microscopy. In a single case an arteriolar lesion suggestive of arteriolopathy due to Cs was seen. Ultrastructural observations of renal tubular cells showed a tendency of rough and smooth endoplasmic reticulum to microdilate and microvacuolize. In 4 out of 22 cases there were mitochondrial alterations with giant mitochondria. In only 1 case, clusters of cilia were seen. Clinical histological correlations show that interstitial fibrosis is directly proportional to CS blood level. CS higher blood levels suggest a higher risk of nephrotoxicity.

Basement Membrane↗
PubMed1983

Cellular localization of keratin in proliferative epithelial processes and neoplasms of the human ovary.

Cytokeratins are one of the intermediate cytoplasmic filaments which contribute to the cytoskeleton. Keratins have recently been demonstrated in normal and neoplastic tissues as well as in human cell lines. It has been suggested that the cellular location of keratin may reflect tissue-specific or epithelial type differentiation. Twenty-three examples of human ovaries containing the full spectrum of epithelial proliferations from inflammatory reactive processes to malignant neoplasia were studied for the cellular distribution of cytokeratin using antisera to human keratin. Nineteen cases contained immunoreactive keratin which was limited to the epithelial cells: 2/2 inflammatory, 8/10 benign tumors, 5/7 borderline tumors, 4/4 carcinomas. There was marked regional heterogeneity in keratin expression such that adjacent morphologically-identical cells could be functionally distinguished by the immunoreactive staining. The predominant cellular localization of keratin varied between histological tumor types in the benign neoplasms: serous = apical, subciliary; endometrioid = apical; mucinous = basal. This pattern was lost in the cytological progression to borderline and malignant tumors. In borderline tumors, the most intense reactivity was noted in areas of cellular atypia and proliferation. In borderline and malignant tumors, keratin was usually present in basal cytoplasmic regions contiguous with stroma.

Carcinoma↗
PubMed1977

Experience of treatment in the Amanita phalloides poisoning (clinical and experimental observations).

Intensive care was applied in 13 patients with acute liver insufficiency and different degrees of metabolic encephalopathy due to the ingestion of Amanita phalloides. Twelve of them were subjected to hepatic assist with E.T., in three cases this measure was repeated. Ten recoveries were obtained, which denote, on the basis of the necrosis enzymes and the hepatic histo-pathological aspects from bioptic samplings, the use of the E.T. method, when applied within the first 72 hours. In pigs poisoned with Amanita phalloides, the clinico-biochemical pattern and the histopathological findings are comparable to the observations in man. Electron microscopy demonstrates peculiar lesion in the cytoplasm. The anatomo-pathological findings in the three dead patients show a liver necrosis over the 90% and the presence of cerebral edema.

Adolescent↗
PubMedDate not supplied

Proton MR spectroscopy in quantitative in vivo determination of fat content in human liver steatosis.

To demonstrate that the lipid volume fraction in liver steatosis can be accurately estimated with in vivo hydrogen-1 magnetic resonance (MR) spectroscopy, the authors developed a calibration procedure based on in vitro MR spectroscopy of lipid extracts from steatotic liver specimens. The lipid volume fractions determined with the calibration procedure were compared with the results of histomorphometry and with calibrated computed tomographic (CT) data. The volume fraction of fat determined with MR spectroscopy was in good agreement with the CT results, whereas histomorphometry underestimated the amount of hepatic fat. The results indicate that determination of the fat volume fraction in steatotic liver can be achieved noninvasively with MR spectroscopy.

Adult↗
PubMedDate not supplied

Growth fraction of colorectal carcinoma (Ki67): a comparative study.

We studied the growth fraction of 55 resected colorectal adenocarcinomas by means of a three-step immunoperoxidase technique (avidin-biotin-peroxidase) using the monoclonal antibody Ki67 directed against a cell proliferation-associated nuclear antigen. The percentage of Ki67-positive cells was evaluated independently by two observers, and a Ki67 score was obtained for each case. No correlation was observed between Ki67 staining and patient's age and sex, tumor size and localization or grading and staging according to Dukes' method (modified by Astler-Coller and Turnbull). The growth fraction showed extreme heterogeneity in the cases examined, within each grade of differentiation.

Adult↗
PubMedDate not supplied

Multitechnical pathological diagnosis in chromophobe renal cell carcinoma.

Two new cases of chromophobe renal cell carcinoma were diagnosed on the basis of their morphology and their karyotype complemented by flow cytometry. In one of these cases, however, all these investigations were not sufficient and additional histochemistry investigation had to be used to completely rule out other renal tumors such as oncocytoma, the prognosis of which is totally different.

Carcinoma, Renal Cell↗