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R Conte

Publications and source records attributed to R Conte.

At least 73 records · Page 4Linked to original sources
PubMed1995

Cell adhesion molecules CD11a and CD18 in blood monocytes in old age and the consequences for immunological dysfunction. Preliminary results.

Adhesion molecules, such as leukocyte-function-associated antigen (LFA-1 or CD11a/CD18), intercellular adhesion molecule 1 (ICAM-1 or CD54) and Hermes antigen (HCAM or CD44), have important roles in many adhesive interactions involving cells of the immune system. Since it has been shown that many immunological alterations were present in aged subjects, we studied the expression and density of these molecules on peripheral blood lymphocytes and monocytes from healthy old subjects. A decrease in monocyte subpopulations bearing CD11a/CD18 and an increase in CD11a/CD18 and and CD44 antigen density on lymphocytes and on monocytes, respectively, were observed. These changes might be an event in the mechanism leading to the decreased lymphocyte proliferative response in vitro and to other immunological dysfunctions reported in old subjects.

Aged↗
PubMed1995

Influence of age and health on immune functions and trace elements.

Apparently healthy elderly donors were screened according to a simple protocol that included clinical examination and the determination of hematological and biochemical values. This screening was performed to detect subclinical alterations which might interfere with immune responses and trace element status. The elderly were divided into two groups. The first group consisted of 22 (age 76 +/- 1 years) positively selected elderly (PSE), i.e. healthy subjects with no hematological and laboratory alterations, the second one comprised 13 (age 75 +/- 1 years) negatively selected elderly (NSE). Data were then compared with those obtained from 40 (age 35 +/- 2 years) healthy young controls. In both groups of elderly donors, plasma zinc levels were normal, while plasma copper concentrations were increased. Intracellular values of zinc and copper in mono- and polymorphonuclear cells from both groups of elderly were within reference limits. After in vitro activation, granulocyte chemiluminescence activity was impaired only in NSE. A decrement in the number of circulating CD3 lymphocytes and an increase in CD8d, CD57 cells were found in PSE, while NSE showed an increased number of CD3,DR cells and CD8d, CD57, CD8b,CD57 and CD16,CD56 positive cells. Our results indicate that only plasma copper levels were affected by age, whereas subclinical alterations in hematological or biochemical values appear to impair immune responses in the elderly.

Adult↗
PubMed1994

Comparative analysis of six different white cell-reduction filters for packed red cells.

BACKGROUND: The reduction of white cells in blood components before transfusion by filters with at least 3 log10 depletion may prevent adverse transfusion reactions such as HLA alloimmunization, febrile reactions, transmitted infections, and immunomodulation. A new generation of filters with 4 log10 depletion is now available. STUDY DESIGN AND METHODS: The aim of this study is to compare the efficiency of white cell reduction by six commercial filters for packed red cells with 3 and 4 log10 depletion (claimed by manufacturers). The analysis of white cell concentration in the white cell-reduced units was performed by flow cytometry and with a Nageotte chamber. RESULTS: The last generation of filters (BPF4, RC400, R01 Plus) show mean residual white cell numbers of 0.18 +/- 0.14, 0.26 +/- 0.21, and 0.25 +/- 0.15 x 10(6), respectively, by flow cytometric analysis and 0.05 +/- 0.04, 0.18 +/- 0.15, and 0.38 +/- 0.23 x 10(6), respectively, by Nageotte chamber evaluation. The 3 log10 depletion filters (R01, Leucostop-4LT-mono, R200) have mean residual white cell numbers of 1.41 +/- 0.92, 2.4 +/- 1.99, and 1.05 +/- 0.64 x 10(6), respectively, by flow cytometric analysis and 3.56 +/- 1.7, 1.67 +/- 1.3, and 3.21 +/- 4.1 x 10(6), respectively, by Nageotte chamber evaluation. The data show that the BPF4, RC400, and R01 Plus filters are likely to be more efficient by 1 log10 reduction than the R01, Leucostop-4LT-mono, and R200 filters. CONCLUSION: The most recent generation of filters is able to deplete white cells from packed red cells by 4 log10; in particular, with one of the filters, the residual WBC content was less than 0.5 x 10(6) per unit in all experiments, while two other filters reached that level in 9 of 10 experiments.

Blood Component Removal↗
PubMed1994

Immunotoxins containing saporin linked to different CD2 monoclonal antibodies: in vitro evaluation.

In this study we describe immunotoxins prepared with different CD2 monoclonal antibodies (mAbs) and a ribosome-inactivating protein, saporin. The CD2 immunotoxins were tested on different models. Anti-CD2-saporin conjugates inhibited protein synthesis by a neoplastic CD2+ cell line (SKW-3) and by an interleukin 2 dependent polyclonal CD2+ lymphoid cell culture (T lymphoblasts), with IC50s ranging from 10(-13) M to 10(-11) M (as saporin). Similar results were obtained with proliferation inhibition tests (3H-thymidine incorporation) on phytohaemagglutinin (PHA) driven lymphoid cultures and on mixed lymphocyte culture activated lymphocytes. Moreover a CD2-ricin A chain conjugate was less effective than an analogous immunotoxin containing the same CD2 mAb and saporin in inhibiting lymphocyte proliferation induced by PHA (IC50 approximately 10(-9) M as ricin A chain versus 10(-12) M as saporin). The conjugates were not toxic on bone marrow stem cells. These results suggest that CD2-saporin immunotoxins could represent an effective tool for CD2+ lymphomas or leukaemias, and for T-dependent immune disorders, such as transplanted organ rejection and graft-versus-host disease.

Antibodies, Monoclonal↗
PubMed1994

Phenotypic, functional and molecular analysis of CD3- LGL expansions indicates a relationship to two different CD3- normal counterparts.

In this study we have analysed the CD3 and TCR transcript expression in three CD3- large granular lymphocyte (LGL) expansions. These LGL populations show a heterogenous attern of expression for CD2, CD8, CD16, CD56 and CD57 antigens. LGL1 is CD2+CD8-CD16+CD56+CD57+, while LGL2 is CD2-CD8+CD16-CD56-CD57-; LGL3 is similar to LGL1, except for CD8 antigen expression. Functional analysis has revealed a different behaviour of these LGL expansions in a cytotoxicity assay against the NK-sensitive K562 cell line. LGL1 and 3 display a significant NK-like activity, while LGL2 is inefficient against K562 target cells. TCR and CD3 transcript characterization of LGL expansions 1 and 3 showed that they expressed multiple TCR delta transcripts, a non-functional TCR beta transcript, CD3-zeta and -epsilon mRNA, but they lacked CD3 delta transcript and they lacked or expressed at very low levels of CD3 gamma transcript. On the other hand, LGL2 expressed TCR delta, CD3-gamma, -epsilon and -zeta transcripts, while it lacked CD3 delta mRNA. On the basis of these data, LGL1 and 3 seem to be closely related to peripheral blood mature natural killer (NK) cells, whereas LGL2 displays a pattern of TCR and CD3 expression similar to that found in CD1-2-3-4-8-16-thymocytes.

Adult↗
PubMed1994

Flow cytometry: a tool in immunohematology for D+W (Du) antigen evaluation?

We performed a flow-cytometric analysis of the expression of D antigen in D+W samples (previously termed Du). We also analysed a series of D-positive and D-negative (cde phenotype) samples to obtain positive and negative controls, respectively. The evaluation was carried out by immunofluorescence and the intensity of positivity was expressed as mean channel value (MCV) of fluorescence. Results demonstrated that D+W samples have lower expression (less than 1 log) than D-positive cases (p > 0.001, Student t test), while cde samples show the same MCVs as negative controls. Moreover, it was also possible to set a grading of D antigen expression and to analyze cases difficult to assess by agglutination only.

Blood Grouping and Crossmatching↗
PubMed1994

Prevalence of peptic ulcer in Helicobacter pylori positive blood donors.

This study aimed to determine the importance of raised antibodies to Helicobacter pylori in an asymptomatic population. A total of 128 asymptomatic blood donors who were seropositive for H pylori and consented to endoscopy were investigated. These subjects were from a population of 1010 blood donors screened for antibodies to H pylori. A questionnaire was completed to determine if any subjects had complained of symptoms, and they subsequently had endoscopy. Altogether 121 of 128 were positive for H pylori by histology and urease test and/or culture and all 121 had chronic active gastritis on histology. Twenty five of these subjects had peptic ulcer (20 duodenal, five gastric), a further 21 had erosive duodenitis, and two were found to have gastric cancer. H pylori associated peptic ulcer disease and duodenitis occur more frequently than previously recognised and this suggests that H pylori infection, even if asymptomatic, is of far greater clinical relevance than originally thought.

Adolescent↗
PubMed1994

Autoimmune neutropenia after unrelated bone marrow transplantation.

A 26-year-old male with Ph+ chronic myeloid leukemia, recipient of an HLA-compatible marrow from a matched unrelated donor, showed good platelet engraftment coupled with poor neutrophil recovery. On day +33 the presence of surface-bound anti-neutrophil antibodies was detected by immunofluorescence. At variance with previously reported cases, the WBC count improved without any specific treatment, and the test became negative on day +42.

Adult↗
PubMed1994

The HLA class I-CML association revisited taking into account the two forms of gene fusion in the Philadelphia chromosome. A multicenter study.

CML patients possess either a b3-a2 or a b2-a2 fusion between the BCR and ABL genes. Depending on the type of fusion, two different series of non-self potentially immunogenic peptides may be produced. If they are presented by HLA class I molecules and recognized by cytotoxic CD8 lymphocytes, individuals could be more susceptible or resistant to leukemic cells bearing one or the other form of fusion according to their HLA class I phenotype. To test this point, the frequencies of HLA-A and HLA-B alleles were compared between b3-a2 and the b2-a2 CML patients. In essence, no difference was found whose significance could withstand correction for multiple comparisons.

Base Sequence↗
PubMed1993

Social skills in the context of learning disability definitions: a reply to Gresham and Elliott and directions for the future.

In this article we review the evidence on the status of a social skills deficit as a learning disability (LD) by examining social skills deficits in the context of learning disability definitions. For the most part, social skills deficits fall within the terms that are specified in the definitions; that is, when there is evidence of neurological involvement, social skills deficit as a learning disability is consistent with the focus on listening and speaking that is characteristic of most definitions of learning disabilities. We also conclude that the absence of limiting conditions in extant definitions of learning disabilities makes it difficult to exclude any particular skill or type of knowledge from falling within the bounds of the definitions. Furthermore, we argue that the critical issue centers on the reformulation of the definition of learning disabilities. We suggest two directions in future work: First, the term "learning disability" should be limited to intentional learning contexts. Acceptance of this limitation would clarify at least some of the confusion regarding the domain of learning disabilities. Second, learning disability definitions should become more responsive to recent research on the nature of learning.

Brain Damage, Chronic↗
PubMed1993

Plasmic levels of trace elements and immune functions in the healthy elderly.

Healthy elderly persons were selected according to an admission protocol which included clinical, hematological and biochemical parameters. Plasmic levels of zinc in these subjects were in the normal range, while plasmic copper was higher than that of young controls. The number of circulating lymphocytes and CD3+ cells was decreased; however, the absolute number of CD4+, CD8b, CD8d, CD20+ and CD57+ cells did not differ from that of controls. A decreased lymphocyte response to PHA in serum-free medium cultures was also observed in the healthy elderly persons.

Aging↗
PubMed1993

Clinical evaluation of an oral contraceptive containing Ethinyl-Oestradiol (30 mcg) and Gestoden (75 mcg).

At the Family Planning Center AIECS in Bari, 383 women have been treated for 6 cycles with an estroprogestinic combination containing Ethinyl-Oestradiol (30 mcg) and Gestoden (75 mcg). We evaluated the following parameters: contraceptive efficacy, cycle control, side effects and acceptability. At the end of the treatment, 346 women (90.4%) decided to continue the treatment while only 22 expressed a negative opinion. The clinical experience has been positively considered by the physician, considering the high contraceptive efficacy, even if 12% of women forgot to take the pill (Pearl Index 0.00) side effects profile and cycle control.

Adult↗
PubMed1992

Heterogeneous immunophenotype of granular lymphocyte expansions: differential expression of the CD8 alpha and CD8 beta chains.

In this study, we have evaluated 14 large granular lymphocyte (LGL) expansions, 11 of which were CD8+. Analysis of the membrane expression of the alpha and beta chains of the CD8 antigen, using specific monoclonal antibodies (MoAbs), has shown that LGL expansions with the CD3+, CD4+, CD8+, CD57+ T-cell receptor (TcR) alpha beta phenotype bear the CD8 alpha/alpha isoform, while the CD3+, CD4-, CD8+, CD57+ TcR alpha beta samples were positive for both the CD8 alpha and CD8 beta chains. These data were confirmed also by messenger RNA analysis. One additional case, with a peculiar phenotype (CD3-, CD2-, CD4-, CD8+, CD57-) and a germline configuration of the TcR beta and gamma chain genes, expressed only the CD8 alpha chain. After additional phenotypic analysis with a wider panel of MoAbs, it was found that the beta chain of the interleukin-2 receptor was constitutively expressed on the majority of the samples tested, and that most of the monoclonal samples coexpressed CD45RA/R0 antigens. Using MoAbs directed against the variable regions of the TcR beta chain, we could show a preferential V beta region restriction in the CD8+ monoclonal cases. This more extensive characterization of CD8+ LGL expansions has further documented the marked heterogeneity within this rare condition and allowed a better phenotypic dissection between the monoclonal and polyclonal cases.

Adult↗
PubMed1992

Serum markers of immune activation and liver allograft rejection.

We monitored the immune response after liver transplantation in 20 patients by measuring the serum levels of soluble interleukin-2 receptor (sIL-2R), soluble CD8 (sCD8), serum amyloid-A protein (SAA), and tumor necrosis factor-alpha (TNF-alpha). In six patients data were available to extend the follow-up period to one year. In all patients mean sIL-2R levels increased in the first month after liver transplantation, and subsequently decreased to values similar to pre-OLT ones, while SAA mean levels rose in the first week after OLT only in patients with rejection. sCD8 levels did not significantly rise after OLT, and TNF-alpha was undetectable in most cases. During episodes of rejection, rejector patients had significantly higher levels of sIL-2R, sCD8, and SAA than stable (without complications) patients. Conversely, no significant difference between rejectors and patients with other complications existed for any of the markers studied. These results diminish the importance of these serum markers of immune activation as laboratory tools in the differential diagnosis of acute rejection from other complications. However, sIL-2R, SAA, and sCD8 levels correlated with the histological grade of rejection and therefore can be utilized to monitor patients with an established diagnosis of acute rejection.

Biomarkers↗
PubMed1992

The incidence of ethanol-induced hypoglycemia.

The purpose of the study was to determine the incidence of ethanol-induced hypoglycemia. All nondiabetic patients who had blood alcohol levels above 0.10% and a random serum chemistry drawn (including glucose) were included. Over a 6-month study period, 378 patients were included in the study. Fifteen patients (4%) presented with hypoglycemia (glucose less than 67 mg%). Of these, four (1%) were profoundly hypoglycemic (glucose less than 50 mg%). Two hundred and fifty three patients (67%) patients were normoglycemic (glucose 67-106 mg%) and 110 patients (29%) were hyperglycemic (glucose greater than 106 mg%). Nonfasting glucose measurements from a control group of 96 nondiabetic, nonintoxicated patients were compared with those of the study group. Two patients (2%) presented with hypoglycemia and none (0%) presented with profound hypoglycemia. Forty-five patients (47%) presented with normoglycemia, and 49 (51%) with hyperglycemia. There were no statistically significant differences found in the hypoglycemia rate between the intoxicated patients and nonintoxicated control population (odds ratio of 0.75; P greater than .05). Four of 378 intoxicated patients (1%) had profound hypoglycemia (less than 50 mg/dL) compared with none (0%) of the 96 nonintoxicated patients. Intoxicated patients had a statistically significant lower rate of hyperglycemia in comparison with the nonintoxicated control group (29% versus 51%; P less than .0001). Age, sex, race, ethanol level, and serum electrolyte measurement had no predictive value for hypoglycemia in intoxicated patients. The anion gap was consistently elevated in hypoglycemic patients in comparison with normoglycemic patients (P less than .05). Hypoglycemia appears to occur as frequently in an ethanol-intoxicated population as in a population without elevated ethanol levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Acid-Base Equilibrium↗
PubMed1992

B-B10 (anti-CD25)-saporin immunotoxin--a possible tool in graft-versus-host disease treatment.

An immunotoxin containing the B-B10 MoAb, directed against the CD25 determinant, and the ribosome-inactivating protein saporin, inhibits 3H-TdR incorporation in phytohemagglutin, allogeneic-stimulated lymphocytes (primary and secondary mixed-lymphocyte reaction), and in an alloreactive T cell clone. A lower degree of inhibition was obtained with the B-B10 MoAb, which is known to inhibit IL-2 activity, as well as with the unconjugated compounds. These results suggest that the in vivo administration of the conjugate might be a more effective tool in the treatment of patients affected by graft-versus-host disease than B-B10 alone, by inducing an efficient killing of allogeneic-reacting T lymphocytes.

Antibodies, Monoclonal↗