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Biomedical subjects

S Sacchi

Publications and source records attributed to S Sacchi.

At least 55 records · Page 3Linked to original sources

Incidence of lymphoid markers in acute myeloid leukemia. Alkaline phosphatase-antialkaline phosphatase versus immunofluorescence.

The aim of the present study was to compare the immunofluorescence technique (IF) with the immunoenzymatic (IE) alkaline phosphatase-antialkaline phosphatase method for the evaluation of the presence of lymphoid antigens (Ag) in 46 cases of acute myeloid leukemia (AML). The first technique allows detection of Ag expressed on the cytoplasmic membrane of living cells, whilst the second shows the presence of intracytoplasmic Ag on fixed cells. In general, the percentages of lymphoid Ag expression on AML cells are relatively low with both IE (15.2%) and IF (17.4%). We found a good correlation between the two methods for CD2 (4/4), CD7 (4/5), CD20 (1/1) and CD4 (2/2). The Ag CD19, CD21 and CD8 were negative in all cases, both with IE and with IF. CD3 (2 cases) and CD22 (1 case) were only evident with IE. CD10 was seen in 1 case with IF, whilst it was found more frequently with IE. For this reason, demonstration of CD10 with IF is more specific for the classification of acute leukemia.

Antigens, CD↗

The use of the alkaline phosphatase-antialkaline phosphatase technique for immunophenotyping acute myeloid leukemia.

The leukemic cells from 31 cases of acute myeloid leukemia were immunophenotyped by the alkaline phosphatase-antialkaline phosphatase (APAAP) technique, using 7 monoclonal antibodies reactive with cells of myeloid origin. We found a good correlation between the results obtained using the APAAP method and indirect immunofluorescence. In most cases, we observed a slight degree of variation in the percentages of reacting cells when comparing the two methods. Nevertheless, taking 20% of cells being immunolabeled as a threshold for defining a case as positive, we found no discrepancies in the final classification of each case. The main advantages of the APAAP method are: (1) its use with routinely prepared peripheral or blood marrow samples, and (2) the possibility of correlating immunological characterization with morphology. Since the results with the APAAP method were comparable with those obtained using indirect immunofluorescence, we suggest that this former technique can complement, and sometimes substitute, other methods of immunological evaluation.

Alkaline Phosphatase↗

Flow cytometry analysis of T cell subsets in skin of patients with specific cutaneous manifestation of B non-Hodgkin lymphoma.

Cutaneous lesions may be the atypical initial manifestation of blood disorder. Monoclonal antibodies identify surface phenotype of lymphocytes present in specific cutaneous lesions. We studied cutaneous infiltrates with flow cytometry in 10 cases of non-Hodgkin lymphoma. We characterized T cell subset in skin immune system. The percentage of T cells was compared to percentage observed in healthy specimens from same patient. T4 cells predominate in cutaneous infiltrates, with an increase in T4/T8 ratio. There was also an increase in T6+ cells, Langerhans cell markers in the skin. HLA-Dr+, T6 cells increased in all cases tested, indicative of dendritic cells. These data showed a modification of T lymphocytes only in skin infiltrate of lymphoma.

CD4-Positive T-Lymphocytes↗

Ratios between the abundance of messenger RNA and the corresponding protein of two growth-related genes, c-myc and vimentin, in leukemia blast cells.

The abundance of the mRNAs of two growth-related genes, vimentin and c-myc, and that of the corresponding proteins have been studied in unstimulated and phytohemagglutinin-stimulated lymphocytes as well as in 18 populations of leukemic blast cells. The quantitative assay was carried out by densitometric scanning of Northern and Western blots. In normal lymphocytes the mRNA and the protein of both genes were almost undetectable. The phytohemagglutinin stimulation led to a sharp increase of the mRNA and the proteins of vimentin and c-myc. The increase was followed by a progressive fall of the gene products. The rate of decrease of the two mRNAs was similar to that of the corresponding proteins. In some leukemic populations very similar amounts of the vimentin protein were accompanied by amounts of the mRNA differing at least 25 times. Not unlikely, very similar amounts of p62c-myc corresponded to mRNA abundances differing at least 16 times. The coordinated biogenesis of both messenger RNAs and proteins, which occurs in mitogen-stimulated lymphocytes, is substituted, in approximately 30% of the leukemic blast cell populations, by molecular events leading to the accumulation of an excess of mRNA.

Blast Crisis↗

Sinus histiocytosis with massive lymphadenopathy: immunological, cytogenetic and molecular studies.

We describe a case of "sinus histiocytosis with massive lymphadenopathy" (SHML) studied by immunohistochemical, cytogenetic and molecular analysis. The immunophenotyping showed that the lymph node histiocytes were strongly positive for the S-100 protein and MoAb LeuM3, OKM5, KP1 and DRC-1; a portion of these cells was also positive for OKT6 and Leu3A, suggesting a possible relationship with the veiled cells, which represent an intermediate step in the pathway from the Langerhans cell to the interdigitating reticulum cell. Cytogenetic analysis showed a normal prevalent clone and a small hypodiploid clone and the molecular study showed no detectable involvement of the c-fms proto-oncogene, which is related to monocyte/macrophages. Unfortunately all these data do not seem sufficient to define the benign or neoplastic nature of the disease. Further investigations, immunophenotypical, cytogenetic and molecular, are needed to elucidate the pathogenesis of the disease, especially for more aggressive cases or for cases with unfavorable evolution.

Blotting, Southern↗

Extramedullary pleural blast crisis in chronic myelogenous leukemia: cytogenetic and molecular study.

Two patients with Ph1-positive chronic myelogenous leukemia with pleural blastic transformation occurring before medullary involvement are presented. The clonal origin of the pleural cells identified as unclassified blasts in 1 patient and as erythroid blasts in the other was confirmed by the presence of the t(9;22) translocation and their clonal evolution by the presence of duplicated Ph1 and additional chromosome alterations. DNA obtained from the pleural blasts and peripheral blood cells of 1 patient showed an identically rearranged bcr configuration, indicating the origin of the pleural blasts from the CML clone and suggesting that this genomic event is not directly linked with the progression of disease.

Aged↗

[Reticular erythematous mucinosis (REM). A report of 2 cases].

Cases of reticular erythematous mucinosis have not been frequently observed since Steinglender discovered the disease in 1971. The two patients with a dermatosis having the clinical and histologic characteristics of REM came to our clinic. The biopsies then taken underwent elective colouring for the mucin and was observed under an electron microscope.

Adult↗

In vivo and in vitro HeNe laser effects on phagocyte functions.

The goal of this work was to evaluate the effect of helium-neon (HeNe) laser irradiation on immunocompetent cells. We used the in vivo skin window method and in vitro granulocyte function tests. The study of cellular migration showed a marked decrease in vitro and in vivo in a dose-independent manner. Superoxide release was not modified by laser irradiation. The granulocyte's aggregation, when using PHA and PMA, presented a reduction that was statistically very significant, not as a subordinate dose. An increase of the release of ATP was demonstrated only at 4 joules and precedes granulocyte aggregation. When using Ca2+ ionophore A23187 as stimulus, laser irradiation at 1, 2 or 4J did not show any modification of granulocyte aggregation. The monoclonal antibody 60.1, which identifies a membrane antigen fundamental for aggregation and chemotaxis, is expressed in normal amounts on granulocyte membranes both before and after irradiation with a HeNe laser. In fact, Laser irradiation preferentially attacks the area of the cellular centrosome that determines a modification of cellular morphology. The electron microscope and immunofluorescence study with a monoclonal antibody have pointed out a disorganization of the microtubules. The alteration of some of the granulocyte functions is correlated to the damage in the centrioles. The granulocyte mitochondrial system and surface membrane remain intact, and this explains the normal production and release of free radicals. Further experiments are necessary to evaluate the clinical application of lasers in various diseases with immunophagocytic pathogenesis.

Adenosine Triphosphate↗

Isodicentric X chromosome in myeloproliferative disorders.

Two further cases of acquired isodicentric (X)(q13) chromosome in patients with myeloproliferative disorders are reported. One patient had a primary myelofibrosis and the other a chronic myelogenous leukemia. DNA replication study demonstrated that both abnormal X chromosomes were late replicating in all cells examined. The inactive condition of idic(X)(q13) seems to be indicative of a selective advantage for a cell carrying this alteration.

Aged↗

Expression of the myeloperoxidase gene in acute and chronic myeloid leukemias: relationship to the expression of cell cycle-related genes.

The expression of the myeloperoxidase (MPO) gene was studied, by means of Northern blot analysis in 14 cases of acute myeloid leukemia (AML), 11 cases of chronic myeloid leukemia (CML), and 6 cases of CML blast crisis, and in HL60 cells before and after induction of terminal differentiation with retinoic acid (RA), phorbol esters (TPA), or vitamin D. The expression of a panel of cell cycle-related genes, namely C-MYC, histone H3, ornithine decarboxylase, P53, vimentin, and calcyclin, was also studied in the same cell populations. Our results indicate that: (a) MPO gene expression (steady state mRNA levels) is strictly confined to the first stages of myeloid differentiation, reaching its peak at the promyelocyte stage and becoming undetectable in mature granulocytes and monocytes; (b) cells devoid of any detectable MPO enzymatic activity such as leukemic basophils have a high content of MPO mRNA; and (c) MPO gene expression is not related to the growth activity of the cell population. Finally, our results show that the pattern of expression of growth-regulated genes in the neoplastic myeloid disorders AML, CML, and CML blast crisis is remarkably different.

Blast Crisis↗

Immunocytochemical evaluation of the percentage of proliferating cells in pathological bone marrow and peripheral blood samples with the Ki-67 and anti-bromo-deoxyuridine monoclonal antibodies.

The monoclonal antibody Ki-67, directed against a nuclear antigen expressed by dividing cells in all the phases of cell cycle except G0 and early G1, was used in combination with an anti-BrdU monoclonal antibody, reacting selectively with cells in S-phase, for assessing the percentage of proliferating cells in bone marrow and peripheral blood samples from patients with lymphoma, leukaemia and multiple myeloma. Immunocytochemical labelling of proliferating cells was performed on marrow frozen sections and/or cytospins using an immunoalkaline phosphatase (APAAP) technique that made it possible to obtain proliferative index measurements in a few hours in contrast to the 3-7 d needed with tritiated thymidine. In the 54 marrow lymphoma cases studied a highly significant correlation was observed between the proportion of Ki-67 (+) cells and the separation into low- and high-grade malignant lymphomas according to the Kiel classification. In patients with multiple myeloma at the first diagnosis, the percentage of Ki-67 (+) cells was low (6-10%). In contrast, a high percentage of Ki-67 (+) cells (40-50%) was observed in a young adult with multiple myeloma, in a patient who first presented at the clinical observation with an extradural mass and in three patients who developed extramedullary masses several years after the initial diagnosis of myeloma. In acute lymphoblastic leukaemias of common type the mean value of Ki-67 labelling was 31.3%. Because of their simplicity and rapidity, immunocytochemical techniques may be expected to replace autoradiography and flow cytometry for the detection of proliferating cells in haematological samples.

Antibodies, Monoclonal↗

Rapidly growing yolk sac tumor of the ovary in a lactating patient.

A case of yolk sac tumor of the ovary exceptional for its size and rapid development is here presented and discussed. The patient was feeding her baby delivered only two months earlier. Hormonal influences of pregnancy and lactation might have played an important role in the progression of this neoplasm.

Adult↗

Cutaneous alternariosis: a rare chromohyphomycosis. Report of a case.

A 66-year-old woman presented 3 groups of scaly granulomatous lesions on the right forearm and elbow of six months duration. Direct examination of the scales showed hyphae and culture in lactrimel medium grew Alternaria sp. considered a contaminant. No improvement was observed after six months of treatment with oral griseofulvin. A second culture using half of a biopsy grew Alternaria sp. again and in histologic examination short pigmented fragments of hyphae surrounded by a granulomatous reaction were seen in the derma. The patient had marked improvement after treatment with erythromycin per os and miconazole topically; an atrophic scar remained as the only sign of the fungal infection.

Aged↗

Platelet alpha-granule release in chronic myeloproliferative disorders with thrombocytosis.

Platelet alpha-granule release in 22 patients affected by chronic myeloproliferative disorders with thrombocytosis and seven subjects with thrombocytosis secondary to splenectomy were studied. We found elevated beta-thromboglobulin (BTG) and platelet factor 4 (PF4) plasma levels in all patients. Intraplatelet content of BTG and PF4 was decreased in patients with idiopathic thrombocythaemia (IT) and idiopathic myelofibrosis (IMF). The BTG and PF4 results were also expressed as the ratio plasma BTG and PF4: whole blood platelet count. In patients with IT, BTG: whole blood platelet count ratio was low, conversely, the same ratio was high in patients with IMF. In conclusion, our results suggest the presence of an abnormal, BTG-deficient clone in IT and a peripheral platelet activation in IMF.

Beta-Globulins↗