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M Giunta

Publications and source records attributed to M Giunta.

33 records · Page 2Linked to original sources
PubMed1994

Immunohistochemical localization of a novel beta 1 integrin in normal and pathologic squamous epithelia.

The 10.1.2 MoAb reacts with a novel alpha chain that associates with the beta 1 integrin chain and is widely distributed among epithelial and endothelial cells of human adult and fetal tissues. In the epidermis and in other squamous epithelia, alpha 10.1.2 chains are expressed exclusively in the basal cell layer. Here we describe the immunohistochemical localization of alpha 10.1.2 in human epidermis, in other squamous epithelia, as well as in cultured keratinocytes. alpha 10.1.2 chain localization has also been investigated in a variety of non-neoplastic and neoplastic lesions of the skin, the uterine cervix, and the lung. We show that alpha 10.1.2 chains retain their basal keratinocyte localization in hyperplastic skin diseases and in benign tumors of the epidermis and that they are strongly expressed in basal cell carcinomas. In contrast, alpha 10.1.2 expression is decreased in keratinocytes that differentiate in vitro and is lost in epidermal dysplastic conditions, in the invading front of squamous cell carcinomas of the epidermis, in microinvasive cervical cancers, and in well-differentiated squamous lung tumors. These findings indicate that alpha 10.1.2 beta 1 integrin is downregulated during keratinocyte differentiation in vitro and in vivo. Moreover, lack of alpha 10.1.2 expression in basal cells of squamous epithelia is associated with early dysplastic changes and with the acquisition of invasive capacity.

Antibodies, Monoclonal↗
PubMed1992

Localization of a novel integrin of the beta 1 subfamily in human tissues.

We have previously described a novel integrin composed of a beta 1-chain non-covalently linked to an alpha-chain which is biochemically different from those known so far (i.e., alpha 1-alpha 7 and alpha v). This molecule has been identified with a monoclonal antibody (MAb) termed 10.1.2 raised against long-term cultured human thymic epithelial cells (TEC). In this study we analyzed the immunohistochemical distribution of this new integrin in a variety of human tissues. MAb 10.1.2 stains several types of endothelial and epithelial cells. Among the endothelia, a strong reaction was detected in the HEV of lymphoid organs including thymus, lymph node, tonsil, and mucosa-associated lymphoid tissue. Epithelial localizations of note were those in the basal layer of the epidermis and of other stratified squamous epithelia, where the lateral and apical but not the deep surfaces of most cells were stained. A variety of water-electrolyte transporting cells in sweat glands, salivary glands, and kidney were also stained at their deep surface. The latter findings suggest that this molecule may subserve other functions in addition to those related to cell adhesion.

Adult↗
PubMed1991

A novel integrin involved in thymocyte-thymic epithelial cell interactions.

Thymocytes differentiate in the thymic microenvironment into immunocompetent T cell through the interaction with a variety of accessory cells, including thymic epithelial cells (TEC). TEC plays an important role in the selection process presenting self antigens in association with major histocompatibility complex (MHC) molecules to the maturing T cells. The T cell receptor recognizes the self antigen-MHC complex, but other surface molecules help stabilize this interaction. Thus, the CD2/LFA-3 and LFA-1/intercellular adhesion molecule 1 pairs have been shown to participate in the binding between lymphoid cells and TEC. Here we describe an integrin of the very late activation antigen subfamily composed by the known beta 1 chain and by a novel alpha chain. This adhesion molecule is expressed on the surface of medullary TEC and is involved in the adhesion between TEC and thymocytes, but not peripheral blood T lymphocytes.

Antibodies, Monoclonal↗
PubMed1989

Resistance of lymphokine-activated T lymphocytes to cell-mediated cytotoxicity.

We observed that lymphokine-activated T lymphocytes, obtained in short- and long-term cultures following stimulation with recombinant interleukin-2 (rIL-2), are resistant to cell-mediated cytotoxicity. In particular, lymphokine-activated killer (LAK) cells do not undergo self-lysis or lysis by alloreactive cytotoxic T lymphocytes (CTL), in line with recent reports concerning CTL clones. Similar findings were further confirmed in a lectin-dependent cell cytotoxicity assay. LAK cell lysis resistance was not due to an inability to recognize itself, since inactivated LAK cells used as cold competitors inhibited tumor cell lysis in a dose-dependent manner. In contrast, the addition on Day 0 of irradiated LAK cells or alloreactive CTL, as well as a CTL clone having LAK-like activity to rIL-2-stimulated cultures abrogated or strongly reduced LAK cell generation. Therefore, LAK cell precursors were most likely susceptible to the lytic activity of differentiated cytotoxic cells, as no inhibition was detected when cell to cell contact was prevented by using a diffusible chamber culture system. These findings, on the whole, suggest that the emergence of the lysis-resistant phenotype is most likely the result of a selective process occurring in vitro that leads to the elimination of lysis-susceptible lymphocytes present in culture.

Animals↗
PubMed1979

[Fluorocarbons as blood substitutes. Toxicity in the rat].

Liquid fluorocarbons, having high solubility for gases (O2, CO2...) have been used as artificial blood substitutes in animals with variable results. The great diversity of these products and the lack of reproductiveness in their composition have not permitted, up to now, a standardization of their utilisation norms. Our work was to study the toxicity, in the rat, of a new kind of fluorocarbon emulsion (E-66, Ugine-Kuhlmann, France) used as an artificial blood substitute during exchange-perfusion. The short survival of the rats is in opposition to the good in vitro results obtained in other experiments (high solubilities of oxygen and dioxide carbon). The toxicity of this fluorinated emulsion is demonstrated by histologic lesions in lungs, liver and kidneys and the great amount of fluor stored in these organs. The mechanism of this toxicity is still to be demonstrated. Hepatic lesions (hyperhemia with dilatation of central veins and sinusoids) and pulmonary lesions (vascular congestion, alveolar oedema) prove a circulatory disturbance leading to right-sided cardiac failure. However, cellular degenerescence lesions, observed in hepatocytes and renal tubular cells, do not permit to exclude formally a cellular toxicity of the E-66 emulsion.

Animals↗
PubMedDate not supplied

Preoperative radiotherapy for resectable rectal cancer: A meta-analysis.

CONTEXT: The benefit of adjuvant radiotherapy for resectable rectal cancer has been extensively studied, but data on survival are still equivocal despite a reduction in the rate of local recurrence. OBJECTIVE: To assess the effectiveness of preoperative radiotherapy followed by surgery in the reduction of overall and cancer-related mortality and in the prevention of local recurrence and distant metastases. DATA SOURCES: Computerized bibliographic searches of MEDLINE and CANCERLIT (1970 to December 1999), including non-English sources, were supplemented with hand searches of reference lists. The medical subject headings used were rectal cancer, radiotherapy, surgery, RCT, randomized, and clinical trial. STUDY SELECTION: Studies were included if they were randomized controlled trials (RCTs) comparing preoperative radiotherapy plus surgery with surgery alone and if they included patients with resectable histologically proven rectal adenocarcinoma, without metastatic disease. Fourteen RCTs were analyzed. DATA EXTRACTION: Data on population, intervention, and outcomes were extracted from each RCT according to the intention-to-treat method by 3 independent observers and combined using the DerSimonian and Laird method. DATA SYNTHESIS: Radiotherapy plus surgery compared with surgery alone significantly reduced the 5-year overall mortality rate (odds ratio [OR] 0.84; 95% confidence interval [CI], 0.72-0.98; P =.03), cancer-related mortality rate (OR, 0.71; 95% CI, 0.61-0.82; P<.001), and local recurrence rate (OR, 0.49; 95% CI, 0.38-0.62; P<.001). No reduction was observed in the occurrence of distant metastases (OR, 0.93; 95% CI, 0.73-1.18; P =.54). CONCLUSIONS: In patients with resectable rectal cancer, preoperative radiotherapy significantly improved overall and cancer-specific survival compared with surgery alone. The magnitude of the benefit is relatively small and criteria are needed to identify patients most likely to benefit from adjuvant radiotherapy. JAMA. 2000;284:1008-1015

Humans↗
PubMedDate not supplied

Natural history of chronic hepatitis C.

BACKGROUND AND AIMS: A comprehensive overview on the course of hepatitis C is not available despite the many studies published. The aim was to review the course and prognostic variables of untreated hepatitis C. METHODS: English-language articles published between January 1989 and December 1997 were identified and data extracted to answer predefined relevant questions. RESULTS: Median chronicization rate, mostly assessed in transfusion-associated hepatitis, was 67%. In retrospective studies, the interval between date of infection and diagnosis of cirrhosis or hepatocellular carcinoma was 20-40 years. Median progression rate from chronic hepatitis to cirrhosis was 27.9% after 8-12 years. Studies obtaining this figure included selected groups of patients and could reflect the worst prognostic segment of the disease. The course of hepatitis C virus infection may be more favourable: cirrhosis rarely or never occurred in young females infected by con-taminated anti-D-immunglobulins; hepatitis was histologically mild in most hepatitis C virus-RNA positive subjects with normal or near normal transminases, predicting non-progressive or very slowly progressive disease; in a population survey from Italy, among 170 infected subjects only 4% had raised transaminases, and none overt liver disease. Increasing age, histological severity, alcohol, possibly male sex and liver iron content were predictors of cirrhosis or increased fibrosis. CONCLUSIONS: Chronicization rate of hepatitis C virus infection is very high. Hepatitis C virus infection can result in a wide prognostic spectrum of liver disease, ranging from cirrhosis and hepatocellular carcinoma to subclinical, nonprogressive disease. Cofactors such as alcohol excess are important in determining the outcome of hepatitis C virus-related chronic liver disease.

Adult↗
PubMedDate not supplied

[Microbiological study of soft cheese purchased in small and middle-sized distribution networks].

The aim of the work is the evaluation of the microbial content of soft cheese when it comes on the table of the consumer. To reach this purpose we have bought, as simple clients, the product in the small and average distributions that apply the HACCP (Hazard Analysis Critical Control Point) plain and in the small distributions which don't apply it, the collecting and the microbiological analysis of the product has been performed on the different pieces that belong to the whole form of cheese during the days of the week, observing a progressive increase of the bacterial number; besides we have found in the bought cheese that when the form of cheese was at the end, values overcame the limits of law. The increase of the bacterial numbers was greater in the products purchased in the average distributions in order with the application of the self-control, and in the small ones that don't effect this type of selling. The deduction was that the HACCP system has not been correctly applied in all the shops tested and in the exercises without the HACCP plain the contamination levels are higher. The health risk connected with not correct manipulation by the employees still results very elevated.

Cheese↗
PubMedDate not supplied

[Use of plastic isolators in the prevention of infection in high risk patients with hematologic diseases].

The authors report a microbiological study of the flora of high risk adults with blood diseases isolated in hermetically sealed plastic isolater. This type of isolation is very effective in the prevention of infections due to hospital germs as such contamination occurred only twice in 292 days isolation and was found in only 0.8% on samples. The efficacy of methods of body decontamination and the incidence of infective complications in our series is also reported.

Adolescent↗
PubMedDate not supplied

[Gastric carcinoma: a histopathological study of 705 cases].

We examined 705 surgical specimens of total and subtotal gastrectomy for gastric cancer, from the Surgical Pathology Department of L'Aquila, Atri and Avezzano, during the period from January 1972 to December 1991. For each case at least 15 samplings were taken, from the tumor itself and from the mucosa which appeared macroscopically normal. The cases were then classified according to the criteria proposed by Lauren and by Ming and the staging of the disease using the UICC's pTNM. Applying Ming's classification, it was evident a clear prevalence of the infiltrative (78.6%), rather than the expansive type (21.4%). Lauren's classification showed a slight prevalence of the diffuse type (56.5%), compared with the intestinal type. Intestinal metaplasia, chronic atrophic gastritis and dysplasia were found more frequently in the intestinal and expansive histotypes. These are the forms having a better prognosis and which in our results represent a minority of cases, therefore identifying the geographic area as a low risk area. With regards to the pTNM staging, T3's resulted the most numerous; T1's, or early gastric cancers (EGC), represented instead 15.7% of the total. Such a percentage is rather high in comparison with the mean percentage in western countries with low risk of disease. In reference to the macroscopic variants, a clear prevalence of the ulcerated forms (66.5%) was noted, in contrast with Ming and other Authors, that declare a slight prevalence of the fungating type. Also considering the histotypes there is a certain discrepancy between the data of Ming and ours; in fact, in our study the infiltrative type prevails, representing 78.6% against 33.6% found by Ming. Such a result can be usefully correlated to the high percentage of the ulcerated forms observed in our study and to the relative scarcity of fungating forms; these variants themselves, according to Ming, are usually related to the expansive type of gastric carcinoma. We also noted, in EGC, a remarkable age difference in regards to the diffuse type; the mean age of the 57 patients with this type classified as T1 was 52.2 years against the 63.0 years of the 341 patients with T > 1. The patients with T1 diffuse type carcinoma were not only 10.8 years younger than the patients with advanced gastric cancer of corresponding histotype, but were also 10 years younger than patients with EGC of intestinal type. Such data could support the hypothesis that EGC, diffuse type, has a peculiar biologic behavior.

Adult↗