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Biomedical subjects

M Clementi

Publications and source records attributed to M Clementi.

240 records · Page 14Linked to original sources
PubMedDate not supplied

Humoral immune response and natural killer activity in patients with mixed cryoglobulinemia.

OBJECTIVE: Based on serological and molecular evidence of hepatitis C virus (HCV) infection in a significant proportion of patients with mixed cryoglobulinemia (MC), a direct association between HCV and MC has been suggested. The goal of the present study was to investigate the role played by HCV and by the immune response to the virus in the pathogenesis of mixed cryoglobulinemia. METHODS: A competitive reverse transcription polymerase chain reaction was employed to evaluate the concentrations of specific HCV RNA sequences in different clinical specimens (plasma, sera, cryoprecipitates, bone marrow and peripheral blood cells). Using recombinant and synthetic peptides covering the HCV core, envelope 1 (E1) and nonstructural regions 4 (NS4) and 5 (NS5), the humoral immune response in a group of MC patients was assessed with an enzyme-linked immunosorbent assay. Natural killer (NK) cell activity was estimated using a 4 hr 51 Cr release assay. RESULTS: Quantitation of the RNA molecules in the biological samples confirmed an increased virion concentration in cryoprecipitates from 13/15 patients with mixed cryoglobulinemia. Analysis of the humoral immune response against the synthetic peptides suggested a distinct response to HCV antigens in MC patients when compared to patients with HCV infection but without serological evidence of cryoglobulinemia. Unstimulated NK cell functioning was below the normal range in all patients tested. However, peripheral blood mononuclear cells showed no enhancement of NK activity by the interferon inducer polyinosinic acid:polycytidilic acid. Enhancement by interferon-alpha was normal, suggesting an impairment in interferon production. CONCLUSION: The quantitative data are in line with the hypothesis of a direct or indirect role of HCV in mixed cryoglobulinemia. The abnormal immune response could be involved in the onset and persistence of HCV infection, and possibly in the appearance of cryoglobulinemia.

Antibody Formation↗
PubMedDate not supplied

[The role of surgery in the treatment of primary carcinoma of the gallbladder. Review of 86 cases].

The records of 86 patients with primary adenocarcinoma of the gallbladder were reviewed. All patients were staged according to the Nevin classification. Twenty-nine patients underwent resection, 57 were submitted to palliative procedures or exploratory laparotomy. Survival was directly related to tumor staging and modality of treatment. The 5- and 10-year survival expectancy after curative resection was 46.8% in stage II patients, 14.2% and 0%, respectively, in stage V patients. None of the unresectable cases survived beyond 24 months, except for one patients who lived 62 months. No significant difference in survival expectancy was found between resectable and unresectable patients with stage V tumor.

Adenocarcinoma↗
PubMedDate not supplied

Molecular monitoring of human immunodeficiency virus type 1 infection.

Over the past few years, considerable technical effort has been directed to developing molecular methods that would allow an effective approach to the diagnosis of human immunodeficiency virus type 1 (HIV-1) infection and its monitoring. Indeed, quantitative molecular techniques have opened the way for a new type of direct study of untreated and treated HIV-1 infected subjects. The understanding of the immunopathogenesis of HIV-1 infection has increased significantly with the introduction of advanced virological and molecular methods for accurate quantitative analysis of HIV-1 activity; powerful methodologies answer (directly and in real time) most questions generated by pathogenic research and by the novel anti-viral strategies introduced in clinical practice. The data from pilot diagnostic applications of quantitative techniques have clarified important features of the natural history of HIV-1 infection. Moreover, an increasing amount of data indicate the need for second-level laboratory facilities for the clinical management of infected patients; virological aspects and some genetic features of the hosts concerning HIV-1 co-receptors (all the co-receptors so far identified are members of, or related to, the transmembrane, chemokine-receptor family) need to be elucidated for the complete diagnostic evaluation of HIV-1-infected subjects.

Antigens, Viral↗