Search PubMed⌕ Search

Biomedical subjects

M Saitta

Publications and source records attributed to M Saitta.

33 records · Page 2Linked to original sources
PubMed1990

Evidence for a DIOA-sensitive [K+,Cl-]-cotransport system in cultured vascular smooth muscle cells.

The existence of a [K+,Cl-]-cotransport system in vascular smooth muscle cells was investigated in the A10 cell line by studying the effect of DIOA (dihydroindenyl-oxy-alkanoic acid, a potent inhibitor) on K+, Rb+ and Cl- fluxes. Hypotonic medium (150 mOsm) increased initial rates of ouabain and bumetanide-resistant (OBR) Rb+ uptake by 100%, bumetanide and DIDS-resistant Cl- uptake by 200%, and OBR net K+ efflux by 130%. DIOA inhibited 40 to 100% of the Rb+ influx and net K+ efflux stimulation with an IC50 of 4 X 10(-5) mol/L. DIOA-sensitive Rb+ influx was a sigmoidal function of the decrease in osmolarity, with a threshold at about 230 mOsm. Our results suggest that vascular smooth muscle cells have a DIOA-sensitive [K+,Cl-]-cotransport system. Dissipation of the outwardly directed Cl- gradient with an apparent [Cl- to K+] stoichiometry much higher than one may provide the energy to ensure net KCl (and osmotic water) extrusion and cell volume regulation in these cells.

Animals↗
PubMed1989

[The immunological profile of children with Down's syndrome].

In 1965 Benda demonstrated that bioptic and autoptic material of children with Down's syndrome showed hypoplasia of the thymus with poor histological differentiation between the cortex and medulla and impairment of Hassal's corpuscles which were also fewer than normal. In the seventies studies revealed the increased susceptibility to infections and higher incidence of leucosis in Down's syndrome patients as well as changes of immunologic defences (in particular cell mediated immunity). This study examines 35 children (16 boys and 19 girls) aged 6 months-20 years. Subjects were divided into a group of 18 cases in poor health with a history of recurrent infections and a group of 17 children in good health. Skin tests were performed by inoculating 0.1 ml of a solution formed by 1 ml physiological solution and 0.1 ml tetanus toxoid. Skin reaction was evaluated 48 hours later. Lymphocyte typing tests were performed with the rosette method and with monoclonal antibodies for T lymphocytes and with the determination of surface immunoglobulins for B lymphocytes. OKT4 (T helper), OKT8 (T suppressor) subsets assayed and the OKT4/OKT8 ratio was determined. Skin tests were negative in 3 cases (8.6%). The number of B lymphocytes was normal in all children. Total number of lymphocytes was decreased in 51.4% of cases. Two subjects had a reduction of OKT4 and 14 had an increased of OKT8 and 16 a significantly lower OKT4/OKT8 ratio. It is clear that skin tests were normal also in those children with low total lymphocyte values. The most closely related parameter to mobility was the OKT4/OKT8 ratio and the most distantly related on was the skin test. Only 3 cases had modifications of all 3 parameters together. Apart from the constant and complete immunological deficit described by many authors and which we cannot confirm the results of this study are in agreement with those of other authors.

Adolescent↗
PubMed1987

Genotypic characterization of common acute lymphoblastic leukemia may improve the phenotypic classification.

The reactivity of five anti-B monoclonal antibodies (McAb)-OKB2 (CD24), B4 (CD19), Leu12 (CD19), BA1 (CD24), B1 (CD20)--as well as the presence of cytoplasmic immunoglobulins (CyIg) were assessed in 100 cases of common acute lymphoblastic leukemia (cALL) at presentation (TdT+, J5 [CD10]+, HLA-Dr+). All cases studied revealed one or more B-cell related markers and a hierarchy in their expression was documented: OKB2 was positive in all cases tested (100%), B4 was expressed in 96.4% of cases, Leu12 in 95.8%, BA1 in 94.9%, B1 in 18.3%, and CyIg in 23%. Further evidence of the B-cell origin of cALL was obtained by molecular analyses at the DNA level which demonstrated the presence of an Ig heavy chain gene rearrangement in all 37 cases assessed, while 37.8% showed a light chain gene reorganization. A genomic subclassification of cALL demonstrated that the majority of cases showed an immature molecular configuration with one (8.1%) or both (54.1%) Ig heavy chain alleles rearranged and a germ-line configuration of the light chain genes; 27% revealed a heavy chain gene involvement and one k allele rearranged. Only four cases (10.8%) showed a more mature configuration with both k alleles rearranged or a gamma chain gene involvement. This study confirms that cALL is characterized by the proliferation of immature B-lineage-committed elements and indicates that the leukemic cells are blocked at different levels of B-differentiation which may be recognized with the use of multiple phenotypic or genotypic B-cell-related markers.

Alleles↗
PubMed1987

[Development of suture materials: from the beginning to our day].

The history of suture materials from the beginnings to the II World War is reported. In this period, catgut and silk were the most employed sutures. The appearance and successive development of synthetic materials revolutionized the field of surgical sutures. This evolution is still active, to the search of ideal suture line.

History, 17th Century↗
PubMed1985

Relevance of anti-T monoclonal antibodies in the study of children with primary immunodeficiencies.

T-cell phenotypic analysis with anti-T monoclonal antibodies (MoAb) was performed on 37 children with immunologic disorders. Abnormalities of T-cell differentiation and/or of T-cell subset distribution were observed in many patients. In particular two infants with severe combined immunodeficiency showed immunologically incompetent common thymocytes (OKT6+) in the circulation, in one case a proportion of OKT6+ cells was OKT4-, OKT8-. A boy with a selective T-cell defect synthetized normal levels of Ig classes, despite the marked reduction of helper/inducer T-cells (OKT4+). Irregularities of T-cell subsets were also noted in children with Wiskott-Aldrich syndrome and in some patients with selective IgA defect or hypogammaglobulinaemia. In one of these, in whom the agammaglobulinaemia was caused by EBV infection, a persistently reversed OKT4+/OKT8+ ratio together with an excessive suppressor T-cell function were found more than 10 years after the onset of the disease. Such a case supports the hypothesis that a viral infection may cause, in a predisposed host, both the agammaglobulinaemia and an abnormality of the regulatory T-cell subpopulations. Such abnormalities, together with those found in the other children studied, underline the importance of MoAb against different T-cell antigens for a better characterization of primary immunodeficiencies.

Adolescent↗
PubMed1984

Different stages of B cell differentiation in non-T acute lymphoblastic leukemia.

Immunoglobulin heavy chain gene rearrangement was evaluated in 19 cases of acute lymphoblastic leukemia (ALL) and correlated with the immunological phenotypic expression on primary or phorbol diester (12-O-tetradecanoylphorbol-13-acetate [TPA])-induced cells. One case of common ALL (cALL), one case of T-ALL, and one undifferentiated acute leukemia that responded to anti-myeloid drugs after unsuccessful anti-lymphoid induction therapy, had germ line heavy chain genes. Rearranged immunoglobulin genes were instead found in 15 of the 16 cALL cases studied and in a case of non-T, non-B, non-common ("null") ALL, which suggested the B cell origin of the neoplastic cells. All cases bearing a heavy chain gene rearrangement were HLA-DR positive. However, the unique cALL case with a germ line configuration was also HLA-DR positive, which confirmed that both the cALL antigen and HLA-DR antigen were not per se expression of B cell commitment. On the other hand, a complete search for B cell-related markers (BA-1 and B1 monoclonal antibodies, as well as cytoplasmic immunoglobulins [CyIg]) in the cALL cases showed that at least one B cell marker could be detected either on primary or on TPA-induced cells in all cases in which a gene rearrangement had occurred. Incubation with TPA allowed the detection of one B cell marker in a case in which the primary cells were negative, and increased the expression of B cell markers in all but one of the cALLs tested. The only cALL case that was not rearranged expressed no B cell markers either on primary or on TPA-induced cells. The non-T, non-B, non-common ("null") case that was rearranged also showed no phenotypic evidence of B cell markers on primary and induced cells. These findings indicate that: (a) practically all cases of cALL appear to be of B cell origin as shown by gene rearrangement analysis; (b) DNA studies are relevant for a more precise characterization of individual cases of undifferentiated acute leukemia; (c) a complete survey for B cell markers may establish the B cell origin of the cALL blasts, as long as the analysis on primary cells is complemented by differentiation induction assessment; and (d) most cases of non-T ALL appear to be characterized by the expansion of neoplastic cells "frozen" at different levels along the B cell differentiation pathway, the first detectable marker being heavy chain gene rearrangement, followed by BA-1, B1, and CyIg expression.

Antigens, Surface↗
PubMed1981

Serum immunoglobulins in homozygous beta-thalassemia.

IgG, IgA and IgM levels were studied in 187 homozygous beta-thalassemic patients and compared with age-matched normal control subjects. The not yet transfused and the polytransfused nonsplenectomized patients showed a significant increase of all Ig classes. The polytransfused splenectomized patients showed a significant increase only of IgG and IgA. The splenectomized patients, when compared to the nonsplenectomized ones, showed a significant increase of IgG, of IgA in the elder ones and a significant reduction of IgM. High ASLO and ASFLO titers were found especially in the splenectomized patients. The high Ig levels in younger not yet transfused patients, with little iron storage and normal hepatic enzyme values, demonstrate that transfusion therapy and liver damage do not play a main role in hypergammaglobulinemia. The absence of antimitochondrial, anticonnective tissue and homogeneous antinuclear antibodies seems to exclude a deficient suppressor mechanism. The hemocatheteric "overworking' of RES may reduce the antigen clearance with a consequent increase of antibody response. Splenectomy, by removing a consistent part of RES, enhances the phenomenon.

Adolescent↗
PubMedDate not supplied

[Lymphedema of the upper extremity in patients operated for carcinoma of the breast: clinical experience with coumarinic extract from Melilotus officinalis].

OBJECTIVES: The aim of this clinical study was to verify the therapeutic activity of cumarinic extract of Melilotus officinalis (CEMO) in patients with chronic lymphedema of the upper arm caused by lymphadenectomy for breast cancer. Cumarine, in fact, has antiedemic properties due to macrophagic action that stimulates proteolysis in the tissues affected by chronic lymphedema. PATIENTS AND METHODS: In an open clinical study we enrolled 24 patients with chronic upper arm lymphedema due to post-lymphadenectomy of the axilla for breast cancer. 21 patients were eligible to receive 400 mg of CEMO containing 8 mg of cumarine in a sole daily administration for 6 months. We measure the circumference of the upper arm at 3 and 6 months from treatment. We evaluated the symptoms and tolerability through a questionnaire given to the patients at every clinical control. RESULTS: Of the 21 (87.5%) patients eligible, only 14 (66.6%) were treated with CEMO according to protocol. Of these 11 patients (52.3%) had a reduction of the circumference of the affected arm of 5% with respect to base values. Three patients (14.2%) had no change. In 12 patients (57.1%) symptoms improved. As for tolerability: 3 patients (14.2%) had transitory gastrointestinal side-effects. There was worsening of lymphedema and symptoms in 4 patients (19%) that did not receive CEMO and were followed as controls. Three patients (14.2%) were not evaluable because they were lost to follow-up. CONCLUSIONS: Cumarinic extract of Melilotus officinalis (CEMO) was effective in reducing lymphedema in 79% of the pts treated for a period of six months. The median reduction of the upper arm circumference was modest (5% with respect to initial values) but statistically significant (p = 0.048). Treatment with CEMO for lymphedema could be associated to the physiotherapy given to these patients such as manual lymph drainage (MLD).

Adult↗