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R Perricone

Publications and source records attributed to R Perricone.

At least 55 records · Page 3Linked to original sources
PubMed1975

Ultrastructure of cell-mediated immunity. I. Comparison between E and EA rosettes.

The ultrastructural comparison between E and EA rosettes showed that, in the former, the rosetting lymphocytes are mostly round in shape and their interaction with sheep erythrocytes only consists of limited areas of membrane contact, in the latter, rosetting lymphocytes are mostly in the shape of uropods and surrounding ox red cells show pseudopods protruding towards the lymphocyte and coming into contact with it.

Animals↗
PubMedDate not supplied

Hereditary angioneurotic edema: clinical and laboratory findings in 58 subjects.

An in-depth analysis of clinical and laboratory findings in 58 patients affected by hereditary angioneurotic edema (HANE) is reported with special focus on problems related to the diagnosis of the disorder. The functional C1 inhibitor (C1INH) assay is the method of choice in the diagnosis of HANE, as it is capable of revealing the disorder with 100% accuracy. The immunochemical assay of C1INH detected HANE in 84.5% of the cases, i.e., immunochemical deficiency of C1INH (type I HANE). C4 was markedly reduced in both type I and type II HANE; thus, C4 levels can be particularly useful when C1INH functional tests are not available. CH50 testing is of little diagnostic value since total hemolytic complement activity is reduced in a variety of other congenital or acquired pathologies involving the complement system. The CH50 assay after incubation in low ionic strength buffer may be utilized in mass screening programs for qualitative evaluation. However, the test has the drawback of not being applicable in cases of frank hypocomplmentemia. While a depletion of the complement classical pathway was detected in most cases, no alteration in the complement alternative pathway was recorded, nor there was any reduction in immunoglobulin levels. Family history was positive in 100% of the cases. Attacks were almost always brought on by stress and/or trauma, though the causes were sometimes unknown. Edema could be cutaneous (non-pitting and non-pruritic) in 94.2%, laryngeal (often life-threatening) in 48% and abdominal (almost always painful) in 88.4% of patients. Associated pathologies were found in 2 patients, i.e., lupus rash and C3NeF-positive chronic membranoproliferative glomerulonephritis, respectively.

Adolescent↗
PubMedDate not supplied

Activation of human complement by crude and purified antigens from Echinococcus granulosus.

Hydatid cyst fluid of Echinococcus granulosus was found to interact with human complement. This interaction resulted in the depletion of hemolytic complement in normal serum and in the electrophoretic conversion of C3 and factor B. The results provided evidence of an activation of complement via the alternative pathway when hydatid cyst fluid was used in the mixtures. Also purified hydatid antigen preparations were found to interact with complement in vitro; this interaction resulted in the consumption of complement not only via the alternative pathway, but also via the classical pathway.

Animals↗
PubMedDate not supplied

Dialysis leukopenia and hypoxemia in a patient without measurable complement activity.

We have studied complement activity, total leukocyte counts, PO2 and acid-base balance during a single hemodialysis with cuprophan membranes in a patient with hereditary angioedema and C3NeF-positive chronic membranoproliferative glomerulonephritis. Before, during and after the dialytic procedure plasma complement activity (total hemolytic complement, classical and alternative pathway activities) was not detectable and no C3-conversion occurred, while profound leukopenia (from 8,500 to 1,800 leukocytes/microliter) and hypoxemia (from 101.8 to 86 mmHg PO2) were found within 20 min from the initiation of hemodialysis. Similar results were obtained by studying the same parameters during two additional hemodialytic procedures. In vitro experiments showed that the patient's C3 could not be converted, either by cuprophan or zymosan, a specific and potent complement activator, even under optimal experimental conditions. Our data demonstrate that complement activation is not the only possible mechanism responsible for early leukopenia (as well as hypoxemia) during dialysis with cuprophan membranes.

Acid-Base Equilibrium↗
PubMedDate not supplied

Increased plasma beta-endorphin levels in hereditary angioedema.

We measured beta-endorphin (BE) and beta-lipotropin (BLPH) plasma concentrations (by means of an HPLC-RIA coupled method) during attacks as well as during symptom-free periods in a group of 28 patients with immunochemical (21) or functional (7) Cl inhibitor deficiency. Thirteen patients suffering from chronic urticaria served as controls. Three orders of considerations prompted us to initiate the present study: the clinical relationship between stress and the onset of acute episodes, the possible effects of repeated stressful situations, as are the attacks themselves, on the patients' neuroendocrine system and the well-known existence of close links between the immune system and endogenous opioids. The results show that plasma BE (and, to a lesser extent, BLPH) is dramatically increased during the attacks. In symptom-free periods many patients show very high BE concentrations, often in the presence of slightly elevated concentrations of BLPH and of ACTH. These observations suggest that patients with hereditary angioneurotic edema show a modified pro-opiomelanocortin-synthesizing cell activity that can result in a massive release of BE from the readily disposable pool present in the pituitary and/or an increase in the turnover of the peptide as evaluated by the BLPH/BE ratio.

Adolescent↗
PubMedDate not supplied

High amounts of beta-endorphin in peripheral blood mononuclear cells from HANE patients.

We measured peripheral blood mononuclear cells (PBMC) beta-endorphin (BE) in patients suffering from hereditary angioneurotic edema (HANE), a disease attributed to C1-esterase inhibitor (C1INH) deficiency inherited as an autosomal dominant trait. Two orders of considerations prompted us to undertake the study reported herein: the presence of elevated plasma BE concentrations in HANE and the demonstration of BE-immunoreactivity in human unstimulated peripheral blood leukocytes obtained from healthy volunteers. Our results show that patients suffering from HANE have a very high BE presence in uncultured, unstimulated PBMC and in unstimulated PBMC cultured for 48 h. At this time high BE concentrations are detected in the culture supernatants. These observations suggest that in HANE patients the same factor(s) involved in causing increased secretion and release of BE from the pituitary (and, in turn, increased plasma BE levels) can play a relevant role also in the determination of high BE presence in PBMC and BE release from the cells.

Adolescent↗
PubMedDate not supplied

Complement activation by cigarette smoke condensate and tobacco infusion.

The capacity of tobacco infusion and cigarette smoke condensate to activate the complement pathway was investigated in vitro by hemolytic and immunological assays. Complement activity was studied using samples of normal human serum incubated at 37 degrees C with different dilutions of tobacco infusion and cigarette smoke condensate. In all mixtures containing tobacco infusion or cigarette smoke condensate at a concentration of 0.1: 1, total hemolytic complement showed an average progressive decrease of 90% and 50%, respectively, after 60 min of incubation. This decrease was associated with a decrease of both classical and alternative pathway activities. In addition, cleavage fragments of C3, C4, and factor B were identified with immunochemical analyses. This study suggests that tobacco infusion and cigarette smoke condensate are activators of complement either through the classical or alternative pathway.

Blood↗
PubMedDate not supplied

T lymphocytes in the synovial fluid of patients with active rheumatoid arthritis display CD134-OX40 surface antigen.

OBJECTIVE: To assess the percentage of T lymphocytes, bearing CD134, a member of the TNF receptor superfamily, primarily found on autoreactive CD4+ T cells in the peripheral blood (PB) and synovial fluid (SF) of rheumatoid arthritis (RA) patients. METHODS: The surface expression of CD134 on SF and PB mononuclear cells was performed by flow cytometry in 25 RA patients and correlated to the disease activity. RESULTS: CD134 expression on CD3+, CD4+, CD8+ and CD25+ cells was higher in SF than in PB of RA patients (P < 0.001). No differences were observed in the percentage of CD134+/CD4+ T lymphocytes in the PB of RA patients and controls. Patients with active RA had significantly higher percentage of CD3+/CD134+, CD4+/CD 134+, CD8+/CD134+ and CD25+/CD 134+ than those with inactive disease. CONCLUSION: These findings suggest that CD134+ T cells are involved in the immunopathological process of RA synovitis, maybe mirroring some other autoimmune disease in which autoreactive T cell infiltrating the target tissues largely coexpress CD134.

Adolescent↗
PubMedDate not supplied

Combination therapy with cyclosporine and methotrexate in patients with early rheumatoid arthritis soon inhibits TNFalpha production without decreasing TNFalpha mRNA levels. An in vivo and in vitro study.

OBJECTIVE: To evaluate the ability of two different combination therapies with prednisone (PDN), methotrexate (MTX) and cyclosporine (CSA) to modulate both TNFalpha transcription and production in early rheumatoid arthritis (RA). METHODS: 24 patients with early RA received a step-down bridge therapy with MTX and PDN (group A). Twelve patients out of the 24 randomly received also CSA (group B). Blood samples and peripheral blood mononuclear cells (PBMC) were collected at different times. TNFalpha levels were measured both in sera and in PBMC supernatants. TNFalpha mRNA was assessed by use of RT-PCR. RESULTS: 10 patients in group A and 9 in group B improved. At baseline, RA patients serum TNFalpha levels were increased compared to controls (p < 0.001) and did not correlate with clinical and serological parameters. These levels decreased within the first month of therapy in both groups, the lower levels being observed in the sera of CSA treated patients. After 30 days of therapy, TNFalpha levels in group B supernatants were significantly lower than those observed in group A, both after 24 and 48 hours of PHA stimulation (p < 0.03 and p < 0.05 respectively). TNFalpha mRNA levels never differed between patients and controls, independently of both the clinical picture and the assigned therapy. CONCLUSION: The addition of CSA to a treatment regimen of PDN + MTX lowers TNFalpha production in vitro without decreasing TNFalpha mRNA expression. This effect could help to induce early immunosoppressive and therapeutic effects during RA.

Adult↗
PubMedDate not supplied

Selection of a new multidrug resistant cell line from Friend leukemia cells by short and cyclic exposures to high concentrations of daunorubicin.

BACKGROUND: Resistance of tumor cells to cytotoxic agents can be due to the overexpression of the mdr 1 gene, which encodes a plasma membrane protein (P-glycoprotein). To understand the molecular basis of multidrug resistance, several laboratories have isolated cell lines resistant to doxorubicin, actinomycin D, vinca alkaloids and related agents. Many months or years of culture with gradually increasing concentrations of cytotoxic agents are necessary to obtain a resistant cell line. METHODS: We selected a new multidrug resistant cell line (MELC-DRTL) by 24-hour cycles of exposure to relatively high concentrations of daunorubicin from sensitive Friend Leukemia cells. After each cycle, the residual live cells were expanded up to the density of 1 x 10(6) cells/ml. RESULTS: The assay conducted with MoAb C-219 showed a high expression on the membrane surface of P-glycoprotein in the MELC-DRTL line, but the fact that it was impossible to obtain a complete reversal of the resistance, even when using high concentrations of verapamil, suggests the presence of other mechanisms unrelated to the presence of P-glycoprotein. CONCLUSIONS: The kind of cellular resistance induction used in this experiment enabled us to obtain an MDR cell line in three months of culture.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

Alpha-interferon in polycythemia vera and essential thrombocythemia.

Twenty-one patients with chronic myeloproliferative disorders, eleven with polycythemia vera (PV) and ten with essential thrombocythemia (ET), were treated with small doses of alpha-2a interferon (IFN). The median follow-up was, respectively, 10.8 months (range 4-22) for PV and 8.11 months (range 4-16) for ET. Six patients with PV and five with ET had been previously treated with conventional cytotoxic drugs, while the remaining patients were newly diagnosed. In four patients with PV we observed a durable normal hematocrit level (PCV less than 0.48) and a reduction of platelet count and spleen size within 4-8 weeks of treatment. Three patients achieved moderate disease control. In the others the disease remained substantially unchanged. Five out of nine evaluable patients with ET showed complete response (CR) within six weeks, one patient had a partial response (PR) and three no response (NR). In one patient with ET the IFN therapy was stopped after twelve days because neurological side effects were observed. All the other patients tolerated long-term treatment very well.

Adult↗
PubMedDate not supplied

[Potentiation of the antiblastic activity of mafosfamide by GM-CSF and interleukin-3: a possible use in the treatment of acute myeloblastic leukemia].

The low activity of antiblastic drugs on tumor cells in the G0 phase is an important limitation in the therapy of malignancies. Cells in the G0 phase are able to enter in cycle any time after chemotherapy treatment, causing relapse of the disease. The use of colony stimulating factors (for example granulocyte-macrophage stimulating factor-GM-CSF and interleukin 3-IL-3) permits the recruitment in cycle of myeloblastic leukemic cells in the G0 phase and thus a cellular population sensitive to chemotherapy. We evaluated the in vitro activity of GM-CSF and IL-3 in fresh myeloblastic leukemic cells: after 96 h of incubation with GM-CSF (500 U/mL), IL-3 (500 U/mL), and GM-CSF + IL-3 (500 + 500 U/mL), 10(6) cells were treated with mafosfamide (30 microgram/mL x 30 min); 10(6) cells were simultaneously treated with mafosfamide without preincubation with colony stimulating factors. The sensitivity of leukemic cells preincubated with GM-CSF and IL-3 to the cytotoxic action of mafosfamide was greater than that of the control cells treated with mafosfamide alone. No enhancement of cytotoxic activity of mafosfamide was observed with GM-CSF + IL-3 combined treatment. The use of colony stimulating factors may effectively increase the number of leukemic cells sensitive to alkylating drugs.

Adjuvants, Immunologic↗
PubMedDate not supplied

Double-stranded RNA excess in hematologic diseases: clinical implications.

Evaluation of double-stranded RNA by flow cytometric analysis is an important parameter for discriminating quantitatively between human tumoral and normal cells. We studied double-stranded RNA (ds-RNA) measurements using propidium-iodide after DNase treatment in bone marrow and in peripheral blood cells from patients with acute lymphoblastic leukemia, acute myeloid leukemia, chronic myeloid leukemia and multiple myeloma. The highest incidence of ds-RNA excess (greater than 30%) was observed in patients with acute leukemia (75%), while those displaying it in complete remission phase were 20-25% and in relapse about 80%. A high incidence was also noted in patients with chronic myeloid leukemia in blastic crisis (100%) and in patients with multiple myeloma with heavy tumor stage myeloma (78%). We never observed an elevated ds-RNA excess in the control group, formed by normal peripheral blood lymphocytes. Indeed the specificity of this tumor marker is attested to not only by its high levels in various hematologic malignancies, but also by its absence in normal cells. Hence the importance of its clinical implications in malignant hematologic diseases is confirmed.

Biomarkers, Tumor↗