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A Latorraca

Publications and source records attributed to A Latorraca.

34 records · Page 2Linked to original sources
PubMed1993

Reduced expression of macrophage-associated antigens on alveolar mononuclear phagocytes from acquired immunodeficiency syndrome.

In this study we evaluated the phenotype of alveolar mononuclear phagocytes recovered from the bronchoalveolar lavage fluid of 24 patients with human immunodeficiency virus infection (AIDS-related complex 8 patients. AIDS 16 patients) and 8 healthy individuals by using a panel of monoclonal antibodies known to react with tissue macrophages, in combination with a flow cytometer. The results showed that 90% of patients with AIDS present a marked reduction in the expression of several antigenic determinants (in decreasing order: CD68, CD36, CR1, CD11c, HLA-DR). The levels of antigen expression by flow cytometry seem to decline with disease progression, showing the most dramatic perturbations in patients with full-blown AIDS associated with pulmonary infections (especially Pneumocystis carinii pneumonia) and lower peripheral CD4 lymphocyte counts. In contrast, patients with AIDS-related complex or AIDS without histological or cultural evidence of pulmonary involvement showed, respectively, only minimal or medium antigenic decreases. However, only a minor proportion (16%, 20%, 20%, 25%, and 25% respectively) of human immunodeficiency virus infected patients (mostly with AIDS) had a significant reduction of the levels of CD4, CD14, CD45R, CD11b, and CD16 antigens in the alveolar macrophages. Since macrophages play a central role in the pathogenesis of AIDS, it may be postulated that the loss of various phenotypic markers on alveolar mononuclear phagocytes (some of them known for their important immunoregulatory actions) could have an important part in the pathogenesis of human immunodeficiency virus induced immunosuppression, and thereby condition the abnormal susceptibility to pulmonary diseases typical of human immunodeficiency virus-infected patients.

Acquired Immunodeficiency Syndrome↗
PubMed1993

[Immunophenotypic study of acute myeloid leukemia (AML): biological significance and prognostic implications].

The immunophenotype of 61 de novo AML referring to the Institute of Hematology of Ferrara between January 1988 and September 1992 was studied in order to evaluate the prognostic impact and the biological implications of this approach. In this study we confirm the possible aberrant expression of some antigens and the lack of a strict correlation between FAB classification and immunophenotype. The expression of the CD14 and CD34 was correlated with a worse prognosis, while the CD34+ patients further showed a lower probability to achieve a complete remission.

Aged↗
PubMed1992

[Fluorocytometric study of proliferation antigens, nuclear proteins and ploidy in acute leukosis].

P53 protein, Ki67 proliferative associated antigen and DNA content have been studied by flow cytometry in the blood blastic cells from 41 patients with acute leukemia. The results were compared with the F.A.B. classification. Cells were permeabilised and fixed by PLP solution before using the FITC conjugated Ki67 MoAb and the p53 MoAb (clone 1801). Propidium iodide and RNAase has been used in order to determine ploidy. Ki67 and p53 protein were found to be expressed at higher level in leukemia cells than in normal bone marrow cells; however there was no correlation between Ki67 and p53 expression and F.A.B. subtype. In acute leukemia patients the range of positivity of Ki67 was 1.1-52.1% while it ranged from 1.8% to 80.1% for the p53 protein. On the basis of these findings we conclude that the flow cytometry evaluation of Ki67 and p53 represents a useful tool for the study of the biologic characteristics of the leukemic cells in patients with acute leukemia.

Acute Disease↗
PubMed1992

Expression of p53 gene in B-CLL peripheral lymphocytes.

The p53 tumor suppressor gene expression has been studied in 23 B-CLL cases at different clinical stages. The analysis failed to show a direct correlation with each stage, but the significantly lower frequency of a BglII RFLP in the pathologic population suggests a role of this gene in B-CLL. Northern Blot analysis showed the expression of p53 mRNA in all the B-CLL cases. A protocol for the RT-PCR methods was set up to study a very small amount of materials which should be better used for sequence analysis.

DNA, Neoplasm↗
PubMed1992

Immunogenotypic characteristics of chronic lymphocytic leukemia patients from northern Italy.

Ig gene analysis, carried out in 25 patients failed to show rearrangement patterns typical of each stage, but, nevertheless, confirmed the monoclonal origin of leukemic cells in these patients. In addition, in 14 of them the pattern of Ig gene rearrangements measured on two different occasions was analyzed. Only in patients who had received chemotherapy, the intensity of the Ig germline band was greater than that of the rearranged bands, indicating the reduction of lymphocytosis after the therapy. Thus, though Ig gene rearrangement could not distinguish the CLL stage, our data confirm the usefulness, at all clinical stages, of Ig gene analysis as a tool in the evaluation of the efficiency of the therapy.

Antibodies, Monoclonal↗
PubMed1992

Lung involvement in systemic sclerosis sine scleroderma treated by plasma exchange.

Systemic sclerosis sine scleroderma can present in some patients as pulmonary interstitial fibrosis. Until now ten cases with this particular clinical variant, all men, have been reported in the literature. The knowledge of systemic sclerosis sine scleroderma presenting as lung interstitial involvement is important in clinical practice for an early diagnosis and correct therapeutic strategy. This work reports the clinico-serological features of two further cases, one a woman, of systemic sclerosis sine scleroderma with prevalent lung involvement, and describes the effects of therapeutic plasma exchange.

Female↗
PubMed1991

Cytochemically unreactive neutrophils from subjects with myeloperoxidase (MPO) deficiency show a complex pattern of immunoreactivity with anti-MPO monoclonal antibodies: a flow cytometric and immunocytochemical study.

Neutrophil granulocytes from 12 subjects with primary myeloperoxidase (MPO) deficiency (six totally deficient) and 16 patients with secondary partial MPO deficiency were tested using two different anti-MPO antibodies, in combination with either a flow-cytometric technique or an immunoalkaline phosphatase staining method. Results demonstrated three different cytofluorimetric patterns of immunoreactivity with the MPO protein: (a) a bright MPO antigenic expression, typical of patients with secondary MPO deficiency (comparable to that observed in the control group); (b) a medium MPO antigenic expression, typical of subjects with primary partial MPO deficiency; and (c) a dim MPO antigenic expression, characteristic of individuals with hereditary total MPO deficiency. No significant differences in granulocyte MPO reactivity were demonstrated for the two antibodies. Furthermore, in two individuals with complete primary enzyme deficiency, the single histogram analysis of MPO fluorescence determined by flow cytometry seemed to show that only 38% (case 1) and 44% (case 2) of neutrophils were reactive with the anti-MPO antibodies: the use of multiple histogram analysis in combination with Kolmogorov-Smirnov statistics allowed us to demonstrated that all the cells express a low density of MPO antigen. These data were more or less confirmed by the APAAP labeling method, which showed a reduced straining only in subjects with primary deficiency, while all patients with secondary deficiency had scores similar to those observed in controls (healthy subjects). Compared with the immunoenzymatic technique, the flow-cytometric procedure showed a higher sensitivity to MPO, being able to estimate even minor decreases in neutrophil MPO antigenic expression, as previously postulated by other authors. This work suggests that patients with primary MPO deficiency have different amounts of MPO antigens in the neutrophil granulocytes, and the levels of MPO fluorescence seem to decline concurrently with the enzyme activity, thereby suggesting the presence of a diminished MPO production. In contrast, the normal antigenic reactivity of neutrophils from patients with acquired MPO deficiency indicates the presence of a functionally inactive form of the enzyme.

Antibodies, Monoclonal↗
PubMed1991

[Cytofluorometric study of myeloperoxidase (MPO) expression in neutrophilic granulocytes of subjects with primary or secondary MPO deficiency: analysis of the histographic antigen distribution using the Kolmogorov-Smirnov mathematical model].

Neutrophil granulocytes from 12 subjects with primitive myeloperoxidase (MPO) deficiency (6 totally deficient) and 16 patients with secondary partial MPO deficiency were tested using two different anti-MPO monoclonal antibodies (MoAbs), in combination with a flow cytometer. Results demonstrated three different patterns of immunoreactivity with the MPO protein:i) a bright MPO antigenic expression, typical of patients with secondary MPO deficiency (comparable with that observed in the control group); ii) a medium MPO antigenic expression, typical of subjects with hereditary partial MPO deficiency; and iii) a dim MPO antigenic expression, characteristic of individuals with hereditary total MPO deficiency. No significant differences in granulocyte MPO reactivity were demonstrated for the two MoAbs. Furthermore, in two individuals with complete primitive deficiency, the single histogram analysis of MPO fluorescence seemed to show that only 38% (case 1) and 44% (case 2) of neutrophil were reactive with the MoAbs anti-MPO: the use of multiple histogram analysis in combination with Kolmogorov-Smirnov statistics allowed us to demonstrate that all the cells express a low density of MPO antigen. These data suggest that patients with primary MPO deficiency have different amount of MPO antigens in the neutrophils, and the levels of MPO fluorescence seem to decline concurrently with enzyme activity, thereby suggesting the presence of a diminished MPO production. On the contrary, in most cases of acquired MPO deficit, the reduced cytochemical activity contrasts with normal antigenic reactivity: this might be the result of the presence of an inactive enzyme.

Antibodies, Monoclonal↗
PubMed1991

Cutaneous and serologic subsets of systemic sclerosis.

The relevance of the extent of skin sclerosis and of other clinicoserological features in diagnosis, severity and prognosis of disease was studied in a large number of unselected patients with systemic sclerosis (SSc). One hundred and fifty-one patients with SSc (126 F and 25 M, mean age 48 +/- 14 SD) followed for 5.3 +/- 3.2 years were included. Patients were divided into 3 cutaneous subsets: limited (68), intermediate (46) and diffuse SSc (37). Serological markers were detected in 288 patients with Raynaud's phenomenon and other connective tissue diseases (CTD). Limited and intermediate SSC prevailed in female patients while the diffuse subset was more frequent in males (p less than 0.0001). Duration of Raynaud's phenomenon before disease onset was shorter in the diffuse variant (p less than 0.0001). A wider cutaneous involvement was associated with more severe forms of SSc. Diffuse subset showed the poorest prognosis at 10 years of followup compared with intermediate (p less than 0.05) and limited variant (p less than 0.001). Intermediate SSc seems a distinct variant of SSc on the basis of clinical manifestations and survival. Among serological markers, anticentromere, anti-Scl-70 and antinucleolar antibodies were found in 21, 40 and 27% of the cases, respectively; these were statistically less frequent (p less than 0.0001) in other CTD. In 83.5% of patients with SSc at least one of these specific markers was recorded. Anticentromere antibodies were correlated to sex (female), limited SSc, calcinosis and telangiectasia. On the contrary anti-Scl-70 was associated with diffuse and intermediate subsets and with more severe SSc manifestations.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Flow cytochemical analysis of peripheral lymphocytes in chronic B-lymphocytic leukemia. Prognostic role of the blast count determined by the H*1 system and its correlation with morphologic features.

Peripheral blood samples from 148 previously untreated patients with chronic B-lymphocytic leukemia (B-CLL) were analyzed with the Technicon H*1 flow cytometer. The absolute number and the percentage values of both LUCs (large unstained cells) and blasts were correlated with survival, as well as with well-known prognostic factors including morphological subtypes of lymphoid cells. Results showed that patients at the most advanced clinical stages (Rai: III and IV; Binet: C) had the highest percentage and count of both LUCs and blasts. Furthermore, the proportion of LUC positively correlated with the following prognostic factors: peripheral lymphocytosis (greater than 50 x 10(9)/l); marked splenomegaly (greater than 10 cm UCM); % of circulating prolymphocytes, % immunoblasts, and % LGL. Our data analysis further revealed that chemotherapy produced a greater reduction of both the LUCs and of the blast count than of that of small lymphocytes. An increase in LUC count was found to coincide with deterioration of clinical status (progressive changes in the clinical stages, occurrence of prolymphocytoid transformation). A rapid increase in blast count was found to occur in concomitance with the development of Richter's syndrome, and correlated positively with the number of peripheral immunoblasts determined by light microscopy. Moreover, a blast percentage higher than 7% had the strongest predictive relation to survival rate when compared with other hematological parameters (lymphocytosis greater than 50 x 10(9)/l, % of LUCs greater than 12%, LUC to lymphocyte ratio greater than 16%, LUCs count greater than 2.2 x 10(9)/l). In the light of these findings, it may be suggested that the presence both of larger proportions of LUCs and of blasts measured with the flow cytometry may be considered unfavorable prognostic factors in B-CLL. However, based on morphological and multivariate statistical analyses, the blast count proved to be the most important prognostic parameter determined by the H*1 system in B-CLL.

Adult↗
PubMedDate not supplied

Audiovestibular involvement in systemic sclerosis.

In order to evaluate the nature and association of audiovestibular disturbances and systemic sclerosis (SSC), 37 unselected SSC patients were studied with a detailed audiological and vestibular examination since November, 1987. Pure-tone audiometry, speech audiometry, impedance audiometry, brainstem response audiometry and vestibular function using electronystagmographic recording were performed. We found a rather frequent audiovestibular involvement (41%). A hearing loss was found in 14 SSC patients; hearing loss was sensorineural in 10 cases and mixed in 4 cases. The latter revealed a finding similar to tympanosclerosis. Four patients showed altered vestibular test values and only one of these had normal hearing. Sensorineural deafness was the more frequent pathological finding and in all cases the site of lesion was cochlear. SSC appears to be directly responsible for audiovestibular damage, since in 12 out of 15 patients with such involvement, no other apparent cause could be revealed. SSC may be included among the autoimmune diseases which may cause audiovestibular disturbances.

Acoustic Impedance Tests↗
PubMedDate not supplied

[Analysis on 149 consecutive cases of intervertebral lumbar and cervical disc prolapse operated with microendoscopic (Metr'X) technique].

Herniated disc patients represent a limited subset of patients with low back pain. Incidence of surgical intervention for lumbar disc pathology is 3% to 4%. The goal of surgery is to achieve neural decompression and relief neurological symptoms. Discectomy through laminotomy is the most common approach. More recently percutaneous approaches to lumbar discectomy, include the use of suction, laser and spinal endoscopy have evolved with mixed results. Microendoscopic discectomy (MED) combines endoscopic technology with the principles of microdiscectomy: open surgical principles are used through a tubular retractor using endoscopic visualization. We present our experience with MED in 149 patients who underwent this procedure. The patient population consisted of 83 men and 66 women aged 18 to 88 years. All patients had substantial relief of their radiculopathy.

Arthroscopy↗
PubMedDate not supplied

Flow cytometric analysis of anti-platelet antibodies in idiopathic thrombocytopenic purpura.

Anti-platelet antibody measurement may be important in defining the pathogenesis of thrombocytopenic states. In this paper we compared three anti-human immunoglobulin reagents by using them to detect anti-platelet antibodies on the platelet surface and in the serum of 14 patients with chronic idiopathic thrombocytopenic purpura (ITP) and 22 thrombocytopenic disorders. Samples were analyzed by both flow cytometry and a fluorescence microscope. In ITP patients, the direct test was positive in 50% of the cases, while the indirect technique proved to be positive in a slightly higher number of those tested (56%). Furthermore, the number of positive cases was similar for the three reagents used in this study, although the mean percentage of positive platelets was higher for the kappa/lambda monoclonal reagent. These data further support the sensitivity and reproducibility of flow cytometry analysis, which was capable of detecting antiplatelet antibodies in all patients with transfused Cooley's disease (regarded as positive control), as well as in a significant number of patients with ITP or related diseases. On the basis of the data presented here, definitive proof regarding the presence of anti-platelet antibodies in patients with thrombocytopenia still has to be found, and further studies are needed in order to ascertain the autoimmune nature of these disorders.

Blood Platelets↗
PubMedDate not supplied

Immunophenotypic and genotypic characterization of B-cell chronic lymphocytic leukemia patients from northern Italy.

BACKGROUND AND METHODS: Immunoglobulin (Ig) gene expression and rearrangements provide information about cell lineage, clonality and differentiation of neoplastic lymphoid cells. We performed flow cytometry and Southern blot analysis in 25 patients with chronic lymphocytic leukemia (CLL) from the Po River delta region (Northern Italy), in order to correlate surface immunological phenotype and heavy and light chain gene rearrangements with clinical stages. RESULTS: In these 25 CLL cases, as in the larger group of 165, k-positive (k+) patients were more frequent than lambda-positive (lambda +) ones by a ratio of 59:41, with a predominance of lambda + in stage II (46:54) and of K+ in stage IV (77:23). However, the survival behavior of lambda + and k+ patients was not statistically different. Ig gene rearrangements were found in all patients in accordance with the immunophenotype. When Ig gene analysis was performed on two different occasions in 7 of the 8 who received chemotherapy, there was an increase in the percentage of the germline band. This variation was inversely related to changes in WBC count. In the treated subject who showed a reduction of both WBC count and the germline, there was rapid disease progression and short survival. CONCLUSIONS: Analysis of Ig gene rearrangements in our CLL patients demonstrated: i) the monoclonality of neoplastic cells; ii) no correlation between rearrangements and clinical stages, and iii) that this analysis may be a useful tool in evaluating biological behavior in selected CLL cases showing a discrepancy between hematological data and clinical response to therapy.

Clone Cells↗
PubMedDate not supplied

Flow cytometry evaluation of urokinase-type plasminogen activator receptor (UPA-R) in acute myeloid leukemia cells.

The aim of this study was to investigate by flow cytometry the expression of the UPA-R (Urokinase type plasminogen activator receptor-CD87) on the blastic population of AML and ALL patients in order to evaluate whether the presence of this molecule could be associated with peculiar clinical and biologic features of leukemic cells. Five different monoclonal antibodies (MoAbs) (clones: 3B10#; VIM5*; 109#; 68#; 100#) were used in order to detect the distinct forms of this cellular receptor. Cell reactivity varied significantly from case to case, also depending on the MoAb used for the flow cytometry analysis. In brief, 3B10# and VIM5* MoAbs were found to be positive in more than 90% of monocytes and neutrophils from healthy subjects, while the number of positive cells was decreased (60%) using the 109# MoAb. However, either 68# and 100# MoAbs recognised only a low number of blood monocytes and neutrophils (8-20%), while lymphocytes were unreactive with all the five UPA-R MoAbs. ALL cells were found to be CD87 negative in all cases. Blasts from AML showed a heterogeneous pattern of expression for the UPA-R MoAbs, being the reactivity strictly dependent on the MoAb used, and, to a higher extent, on the degree and type of maturation of the blastic cells. The number of blasts recognising 3B10# and VIM5* MoAbs was significantly higher than that reacting with the remaining MoAbs irrespective of the FAB subtype. Since proteolytic enzymes, like UPA, play a key role in the dissolution of the extracellular matrix, and in facilitating the cell egress from the bone marrow, it is conceivable that the expression of the UPA-R could contribute to the invasive properties and, possibly, metastatic potential of leukemic cells.

Acute Disease↗