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Biomedical subjects

M Ricci

Publications and source records attributed to M Ricci.

At least 145 records · Page 8Linked to original sources
PubMed1991

Gastrointestinal cancer follow-up: the effectiveness of sequential CEA, TPA and Ca 19-9 evaluation in the early diagnosis of recurrences.

One-hundred and seventy-four consecutive patients who underwent curative resection for gastric and colorectal cancer between 1983 and 1985 were studied prospectively to evaluate the roles of sequential carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA) and Ca 19-9 determinations and independent clinical examinations, in the early diagnosis of resectable recurrences. Sixty-six recurrences (33 from gastric and 33 from colorectal cancer) were detected between 6 and 42 months after primary surgery. In gastric cancer CEA, TPA and Ca 19-9 showed a sensitivity of 64%, 73% and 60% respectively and a specificity of 67%, 65% and 54% respectively. Nine patients (27%) underwent surgical treatment for recurrent disease, and four of these (44.4%) had resectable recurrence, for a total resectability rate of 12%. Of these four patients, three are still living after 12, 36 and 44 months respectively from re-operation without evidence of neoplastic disease. In one of these patients, re-operation was performed on the basis of the elevation of the three markers, without any other clinical sign of disease. This patient had a resectable solitary hepatic recurrence. In colorectal cancer. CEA, TPA and Ca 19-9 showed a sensitivity of 73%, 73% and 49% respectively, and a specificity of 77%, 87% and 97% respectively. Fourteen patients (42.4%) underwent surgical treatment for recurrent disease and eight of these (57%) showed resectable recurrence, for a total resectability rate of 24.2%. Six patients are still living after 9, 16, 21, 31, 41 and 53 months respectively from re-operation without evidence of neoplastic disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Neoplasm↗
PubMed1991

Increased numbers of Th2-like CD4+ T cells in target organs and in the allergen-specific repertoire of allergic patients. Possible role of IL-4 produced by non-T cells.

Phytohemagglutinin (PHA)-induced human T cell clones (TCC) derived from conjunctival flogistic tissues of 3 patients with vernal conjunctivitis produced unusually high amounts of interleukin-4 (IL-4) and no, or limited amounts of, gamma-interferon (IFN-gamma). Allergen (Dermatophagoides pteronyssinus or Lolium perenne group I)-specific TCC derived from peripheral blood of two atopic donors produced significantly higher amounts of IL-4 and significantly lower amounts of IFN-gamma than TCC specific for bacterial antigens (tetanus toxoid and PPD) contemporarily established from the same donors. These data provide evidence for a compartimentalization of Th2-like helper T cells in target organs and in the allergen-specific T cell repertoire of allergic patients. Non-B, non-T bone marrow cells could produce IL-4, but not IL-2 or IFN-gamma, in response to cross-linkage of Fc epsilon type I receptors. These cells may further contribute to the maintenance and amplification of allergic inflammation.

Allergens↗
PubMed1991

Purified protein derivative of Mycobacterium tuberculosis and excretory-secretory antigen(s) of Toxocara canis expand in vitro human T cells with stable and opposite (type 1 T helper or type 2 T helper) profile of cytokine production.

A large series of T cell clones (TCC) specific for purified protein derivative (PPD) of Mycobacterium tuberculosis (total 60) or Toxocara canis excretory/secretory (TES) antigen (total 69) were established from the peripheral blood of two healthy individuals and analyzed for their profile of cytokine production in response to stimulation with either the specific antigen or the polyclonal activator phorbol myristate acetate plus anti-CD3 antibody. Under both these experimental conditions, the great majority of PPD-specific TCC secreted IL-2 and IFN-gamma but not, or limited amounts of, IL-4 and IL-5. In contrast, most TES-specific TCC secreted IL-4 and IL-5 but not, or limited amounts of, IL-2 and IFN-gamma. PPD-specific TCC that failed to secrete IL-4 and IL-5, and TES-specific TCC that failed to secrete IL-2 and IFN-gamma, were found to lack transcripts for IL-4 and IL-5, or for IL-2 and IFN-gamma, respectively. During the course of the study, over a 6-mo period, the functional phenotype of both TES- and PPD-specific TCC was repeatedly assessed and remained constant. These data demonstrate that T cells with stable Th1 or Th2 functional pattern exist not only in mice but also in humans and suggest that in the course of natural immunization certain infectious agents preferentially expand T cell subsets with stable and definite profile of cytokine production.

Adult↗
PubMed1991

Chondrosarcoma of the soft tissues. Two different sub-groups.

Chondrosarcomas arising from soft tissues are rare. Two different varieties are described, myxoid and mesenchymal. We have collected nine cases of the tumour, five myxoid and four mesenchymal, from a review of 513 cases of chondrosarcoma seen between 1904 and 1988. We report the principal clinical, radiographical and histological differences between the two varieties and discuss their surgical treatment and prognosis.

Adult↗
PubMed1991

T cells, IgE antibodies, cytokines and allergic inflammation.

T helper cell (Th) subsets producing interleukin 4 (IL-4) or gamma interferon (IFN) play a reciprocal role in the regulation of human IgE synthesis. Though necessary, IL-4 alone was insufficient. Patients with hyper-IgE had significantly lower proportions of T-cells that produce IFN and TNF, but not IL-2 or IL-4. In patients with helminth infections or atopy production of IgE and eosinophilia may result from expansion of Th-2-like cells. T cell clones (TCC) specific for allergens and Toxocara canis (TES) showed dichotomy in cytokine secretion. Non-atopic donors gave insufficient TCC for comparison. Activation of the fibroblasts of the respiratory mucosae induces production of interstitial proteins such as collagen III, V, fibronectin.

Airway Resistance↗
PubMed1990

Noncognate contact-dependent B cell activation can promote IL-4-dependent in vitro human IgE synthesis.

We have previously shown that IL-4 is an essential mediator for the synthesis of human IgE in vitro. In this study we demonstrate that prior physical contact with T cells is required by B cells to synthesize IgE in response to IL-4. Both autologous and allogeneic freshly prepared T cells were consistently able to support IL-4-dependent IgE synthesis, provided that they were added to B cells together with, or before, the addition of IL-4. In addition, most CD4+, as well as a proportion of CD8+, PHA-induced T cell clones (TCC) established from two HLA-DR incompatible donors, supported, in the presence of exogenous IL-4, the synthesis of IgE in B cells from the majority of individuals tested including both donors of cloned T cells. An alloreactive TCC able to produce IL-4 in response to HLA-DR4+ B cells and to induce HLA-DR4+ B cells to synthesize IgE, acquired the ability to support IgE synthesis by B cells lacking the appropriate alloantigen provided that exogenous IL-4 was added. Although the ability of freshly prepared T cells to support IgE synthesis was consistently abrogated by fixation with paraformaldehyde (PF), such a treatment variably affected the IgE-inducing ability of TCC. Preactivation with anti-CD3 before treatment with PF maintained or even enhanced the ability of TCC to support IL-4-dependent IgE synthesis. More importantly, preactivation with anti-CD3, followed by fixation with PF, enabled TCC, apparently devoid of IgE-inducing activity in unfixed condition, to support IL-4-dependent IgE synthesis. Taken together these data suggest that at least two signals are involved in the triggering of human B cells to IgE production: the first is delivered by a T-B cell contact and the second by IL-4. The physical signal delivered by T cells does not necessarily consist of cognate interaction. Non-cognate contact-dependent induction of B cells to IgE synthesis in response to IL-4 appears to be related to molecule(s) distinct from the TCR/CD3 complex, but fully expressed on the membrane of TCR/CD3-activated T cells.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1990

Immunological abnormalities in a group of patients with limited cutaneous systemic sclerosis and prominent vascular disease.

Antinuclear antibodies, circulating immune complexes, rheumatoid factors and anticardiolipin antibodies were detected in the sera of 17 patients affected by the limited cutaneous subset of systemic sclerosis and marked clinical evidence of ischaemic cutaneous lesions (fingertip ulcerations). This study was designed to evaluate the possible role of anticardiolipin (aCL) antibodies and other immunological disorders in the endothelial damage characteristic of the disease. ACL antibodies were found in 41% of the patients. With the exception of a significant connection with positive rheumatoid factor tests (RIA), no notable associations between anticardiolipin antibodies and antinuclear antibodies, circulating immune complexes (CIC), and other serological abnormalities were found. ACL antibodies did not significantly correlate with the presence of vascular lesions in our patients. However, a role of these antibodies in endothelial damage cannot be excluded, possibly in association with other serum factors such as immune complexes and antinuclear antibodies. A positive connection between the incidence of CIC and the severity of lung perfusion impairment was observed, and the previously reported relationship between anticentromere antibodies and calcinosis was indirectly confirmed.

Adolescent↗
PubMed1990

[Duties and responsibilities of hospital services in reference to autotransfusion practice as provided by the May 4, 1990 law No. 107].

The Authors report the aims of the law 4/5/90 n. 107, as regards to the "diffusion" of autotransfusion practices, pointing out the responsibilities of hospital services named by the law. These services are immunohematology and transfusion services, sanitary directions, surgery divisions and anesthesiology services, with reference to articles 5,6 and 16. Finally, they point the forensic medical problems concerning the possibility of an homologous use of predeposited blood.

Blood Banks↗
PubMed1989

Magnesium monoperoxophtalate: an efficient single oxygen atom donor in DNA cleavage catalyzed by metalloporphyrin.

The peracid compound magnesium monoperoxophtalate (MMPP), water-soluble at physiological pH, behaves as a promising oxygen donor in the oxidative cleavage of DNA catalyzed by meso-tetrakis-(4-N-methylpyridyl)porphyrinatomanganese(III) pentaacetate. Shown on cleavage of supercoiled phi X174 DNA, MMPP is significantly more efficient than KHSO5, another recently developed single oxygen atom donor (Fouquet et al., J. Chem. Soc., Chem. Commun., 1987, 1169).

Bacteriophage phi X 174↗
PubMed1989

Brenner tumor of the ovary: a correlative histologic, histochemical, immunohistochemical, and ultrastructural investigation.

The histologic, histochemical, immunohistochemical, and ultrastructural features of Brenner tumor (BT) were studied. BT was compared with transitional bladder cells, and close similarities between the two tissues were identified. Abundant glycogen in all cellular layers, an alcianophilic/sialomucinic surface mucous coat, and argyrophilic cells characterized both BT and bladder epithelium. Immunohistochemically, chromogranin and neuron-specific enolase reactivity was observed in all cases examined. An additional relevant finding was the presence of serotonin-storing cells in both BT and urothelium. Moreover, carcinoembryonic antigen, epithelial membrane antigen, and keratin reaction were found in BT and urothelium, indicating an additional antigenic similarity. Additionally, malignant Brenner tumor was ultrastructurally found to share many common features with the bladder tissue. The distinct histochemical, ultrastructural, and antigenic pattern of BT, primarily of the transitional type, is emphasized.

Brenner Tumor↗
PubMed1989

Immunoregulation in clinical diseases: an overview.

The quality, magnitude, and persistence of each immune response results from the net balance of different influences that may amplify or decrease it. The complex interaction between such influences underlies the concept of immunoregulation. Comprehension of the complex mechanisms of immunoregulation has the potential to yield important insights into the genetic and the molecular basis of the physiology of immune responses and of the pathophysiology of a wide number of clinical diseases. The principal basic mechanisms of immunoregulation comprise the systems of recognition structures regulating antigen specificity of immune responses and the interconnecting systems involved in the overall regulation of immune responses. Such regulatory interconnecting systems include regulatory T cells, idiotypic network, isotopic network, and the intricate web of interactions between cytokines (cytokine network). In addition, there is now evidence that these highly complex and sophisticated regulatory systems are not only interrelated to each other, but are themselves regulated by signals originated outside the immune system (e.g., from the nervous or the endocrine apparatus). These alterations of immunoregulatory mechanisms are involved in the pathogensis of many groups of human diseases, such as immunodeficiencies, neoplastic and immunoproliferative disorders, many infectious diseases, atopic disease, and autoimmune disorders. A rational knowledge of immunoregulation will hopefully have great practical implications for future strategies of diagnosis and treatment of diseases in which deranged immune functions play a major role.

Autoimmune Diseases↗
PubMed1989

Role of interleukins in induction and regulation of human IgE synthesis.

Studies of human IgE synthesis are summarized and provide further insight into the cellular and molecular mechanisms involved in IgE regulation, as well as in the alterations responsible for IgE disregulation in some pathological conditions. These include the demonstration that IL-4 is the essential factor for the induction of human IgE syntheses. Another T cell-derived lymphokine, IFN-gamma negatively regulated the IgE synthesis induced by IL-4. These two lymphokines can be produced by different T helper cells, as shown in mice, but they can also be the product of the same T cells clones. Additional cellular and/or molecular signals appear to be involved in the IL-4-induced IgE synthesis, but their precise role in this process is undetermined. Finally, alternations of one or more of these regulatory mechanisms can be detected in patients with pathological conditions characterized by hyperproduction of IgE. In particular, the increased prevalence of T cells clones able to produce IL-4 appears to be a distinctive feature of patients with common atopy whereas a reduction in the proportion of IFN-gamma-producing T cells seems to be peculiar of both patients with hyper-IgE syndrome and patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Recent advances in the understanding of humoral and cellular mechanisms implicated in thyroid autoimmune disorders.

In this review new data are reported indicating that the thyroid microsomal-microvillar antigen can be identified with thyroid peroxidase (TPO). This concept derives from binding studies of monoclonal and polyclonal microsomal antibodies to TPO purified by affinity chromatography or obtained by recombinant DNA technology. Furthermore, immunofluorescence studies performed on cultured thyroid cells have shown the presence of a TPO-related antigen on the surface of the cells. The expression of the TPO antigen is modulated by TSH through the cAMP pathway. The functional activities of TSH receptor autoantibodies have also been characterized. From these studies the following conclusions can be drawn: (i) TSH receptor antibodies possess multiple biological activities, interfering or mimicking TSH actions; (ii) a good correlation is observed between stimulation of adenylate cyclase and of iodide uptake by Graves' IgG. In these IgG preparations, adenylate cyclase- and growth-stimulating activities cannot be separated; (iii) antibodies blocking the TSH-dependent AC are present in patients with autoimmune hypothyroidism; (iv) a mixture of stimulating and blocking antibodies may coexist in the same patient, whose clinical status may result from the sum of the biological activities of these antibodies. Finally, new data are reported on the identification and characterization of T cell clones infiltrating the thyroid tissue of subjects with thyroid autoimmune disorders. The majority of these clones were CD8+ cytolytic T cells with natural killer activity. These latter data may be of importance in the mechanisms of thyroid damage observed in Hashimoto's glands.

Antibody Formation↗