Search PubMed⌕ Search

Biomedical subjects

G Dighiero

Publications and source records attributed to G Dighiero.

At least 145 records · Page 8Linked to original sources
PubMed1980

Two new applications of the immunoperoxidase method: cell-by-cell quantitation of surface immunoglobulins and automated recognition of B-lymphocytes.

Two new applications of the immunoperoxidase method are reported. In the first one, cells after incubation with antibodies coupled with peroxidase washing and staining by carbazol are cytocentrifuged and individually analyzed for their content on surface immunoglobulin (Ig) in two photometric microscopes. The results included the following: 1. Maturation of mice B-lymphocytes during ontogeny is accompanied by the appearance of a population containing intermediate to high amounts of SIg. 2. The CLL B-lymphocyte pattern as compared with that of normal B-lymphocytes shows a decrease of SIg and a homogeneous distribution. In the second application, mice splenic lymphocytes are incubated with antimouse Ig coupled with peroxidase and analyzed through Hemalog D. B-lymphocytes are separated from T-lymphocytes in a distinct population since they become positive for peroxidase.

Aging↗
PubMed1980

[Prognostic value of the study of lymphocytic volumes in chronic lymphocytic leukemia (author's transl)].

The modal volume of peripheral blood lymphocytes from 23 patients with chronic lymphoid leukemia (CLL) was measured by a Coulter ZBI linked to a channalyzer C 1000, varied from 140 to 262 mu3. A statistical correlation between the modal volume and anatomo-clinical forms of the disease was determined: a modal volume below 190 mu3 was statistically found among early forms while a volume over this threshold corresponded to advanced forms. Since Sipe et al. postulated that cell volume might be relayed to the cell kinetics, we attempted to determine the volume distribution law of lymphocytes from 12 CLL cases by applying the chi-square distance test. The best adjustment was observed with the two log-normal populations model, but this adjustment was acceptable for only five cases over twelve. The instability in the determination of the percentage of the second population made it impossible + relate it with the proliferative cell fraction. Moreover, this model did not provide more significant information than the single modal volume.

Aged↗
PubMed1980

Computer analysis of platelet volumes.

A Coulter ZB was used to measure electronically the size of circulating platelets collected from normal subjects. EDTA or ACD were used for collection. Three mathematical models of volume histograms were tested. The lognormal law model is clearly unacceptable if all particles are used, but is applicable in the particle range of 3-15 mu 3. The model of a mixture of two lognormal populations closely approximates observed volume distribution. The model of three lognormal populations also approximates well when the largest volume population is divided into two subpopulations. The contribution of these results to an understanding of heterogeneity in platelet size is discussed.

Computers↗
PubMed1979

Detection and quantification of platelet-bound antibodies with immunoperoxidase.

The use of immunocytochemical techniques enables one to quantify antibodies bound to cell membranes. We have tested the platelets of subjects with immune thrombocytopenic purpura by this method. The washed platelets were incubated in the presence of antiglobulin conjugated with an equimolar amount of peroxidase. The fixed peroxidase was revealed and quantified by an enzymatic reaction using orthodianizidine-H2O2. From the results the number of immunoglobulin molecules per platelet was calculated. The test was calibrated so as to eliminate non-specific fixation of the reagent. Under these conditions the platelets of subjects with idiopathic thrombocytopenic purpura bound a much large amount of detectable immunoglobulin (800-21 000 molecules per platelet) than those of normal subjects (235 +/- 74 sites per platelet) or subjects with non-immune thrombocytopenia (395 +/- 203 molecules per platelet).

Antibodies↗
PubMed1979

Identification of a pure splenic form of chronic lymphocytic leukaemia.

We have recently proposed a new staging system for chronic lymphocytic leukaemia (CLL) in which patients with isolated splenomegaly are classified into a distinct stage (stage II). Twenty-three such patients (from two institutions) have been studied without recorded death in a follow-up of 18 months to 30 years. This favourable prognosis justifies separation of these 'pure splenic forms' (SCLL) which must be distinguished from what Galton has termed prolymphocytic leukaemia (PL). This distinction can be made on the basis of three criteria: (i) Clinically, SCLL has a slow uneventful course and neither anaemia and/or thrombocytopenia: (ii) cytologically PL can be distinguished from other forms of CLL though atypical forms of CLL may be confused with the former; and (iii) the study of surface membrane immunoglobulins (SmIg) showed that while lymphocytes from most patients with both PL and SCLL bore uniform SmIg, suggesting a monoclonal B-cell proliferation, there was a major quantitative difference in that whereas PL lymphocytes had a number of antigenic sites close to that of normal lymphocytes (mean: 82 000 sites per cell), SCLL lymphocytes had a drastically reduced number of sites. It is our opinion that this is an important criterion for the differential diagnosis between PL and SCLL.

Aged↗
PubMed1979

Correlation between lymphographic grouping and anatomic and clinical stages in chronic lymphoid leukemia.

In a retrospective study of lymphograms in 55 patients with chronic lymphatic leukemia observed 42-170 months, four lymphographic groups were established according to lymph node size and morphology. In group 1, the lymph nodes were only slightly enlarged and pathologic in appearance. In group 2, the nodes were moderately enlarged and appeared reticular. In groups 3 and 4 the nodes were greatly enlarged and appeared foamy, striated, or "ghostlike" (similar to those seen in lymphoma). The correlation between the lymphographic groups and a new clinical classification (stages O-IV), which has been demonstrated to have prognostic values, was statistically significant: clinical stage O and lymphographic group 1; clinical stages III and IV and lymphographic groups 2, 3, or 4. Clinical stages 1 and II were dispersed throughout the different lymphographic groups. Although the specific prognostic value of the results of lymphography is not apparent in clinical stages O-II, it does seem to be established in stages III and IV. In these stages, the number of deaths was significantly greater in patients in lymphographic groups 3 and 4 when compared with those in lymphographic group 2.

Adult↗
PubMed1979

[Contribution of new methods of quantitative cytology and immunology to the understanding of lymphoproliferative syndromes].

Seventy one patients with a lymphoid hemopathy, three with agammaglobulinemia and six normal controls were investigated with regard to their blood lymphocyte membrane-associated light chains. Detection and quantitation of antigenic determinants were performed by means of peroxidase-labeled antibodies. Compared to normal controls, values found in chronic lymphocytic leukemia (CLL) were very low (tenfold decrease). The number of antigenic determinants on lymphoid cells from patients with blast crises supervening in CLL, prolymphocytic leukemia, Waldenstrom's macroglobulinemia and Burkitt cell acute leukemia were significantly higher than those seen in patients with CLL. The data obtained in this investigation through quantitative immunocytology constitutes a new parameter for the classification of lymphoid hemopathies and for an approach to their pathogenesis, in particular if the quantity of membrane immunoglobulin correlates with the stage of cell maturation.

Antibodies↗
PubMed1978

[Comparative study of the peripheral lymphocyte count in controls and in patients with chronic lymphocytic leukemias 4 hours after injection of hydrocortisone (author's transl)].

The peripheral lymphocyte count was investigated prior to and 4 h after a single intravenous injection of 400 mg of hydrocortisone (HSHC) in 23 controls and 43 patients with chronic lymphocytic leukemia. A reduction in the peripheral lymphocyte count was observed in all normal controls, the mean decrease being 51.9%, with differences according to age.

Aged↗
PubMed1978

[A new parameter for chronic lymphocytic leukemia : determination of the large lymphocytes by means of Hemalog D (author's transl)].

The munber of large peripheral lymphoid cells and the ratio of these large unstained cells (LUC) to the total number of peripheral lymphocytes were determined by means of the Hemalog D in 57 patients with chronic lymphocytic leukemia (CLL) and in 100 controls. While the absolute number of LUC per mm3 is simply a reflection of peripheral lymphocytosis, the ratio LUC/total lymphocyte count was shown to correlate with clinical staging. In controls, this ratio ranged from 3.2% to 11.2%. In CLL is was less than 11.2% in 43 patients and less than 11.2% in 14 patients. This latter group corresponded statistically to patients with advanced disease in our clinical staging system (stages III and IV). An increase in the LUC/total lymphocyte ratio is therefore a statistical criterion of poor prognosis.

Autoanalysis↗
PubMed1978

Visualization of tubulin in lymphocytes. I. Comparison of normal and chronic lymphocytic leukemia (CLL) lymphocytes.

Cell structures containing tubulin were studied in peripheral blood lymphocytes from 8 normal donors and 11 patients with CLL using specific antitubulin antibodies revealed by immunoperoxidase assay. The centriole and microtubules were clearly visible in both groups. A "nucleus-associated tubulin-containing structure" was revealed by antitubulin antibodies and was found in virtually all lymphocytes of normal subjects but in a considerably lower number of CLL lymphocytes. The nature of this structure and its relationship to other cell structures are discussed.

Adult↗
PubMed1978

Ontogeny of B lymphocytes in mice. Quantification of surface membrane immunoglobulins by immunoperoxidase assay.

Surface membrane immunoglobulins (SmIg) of splenic lymphocytes were investigated by immunoperoxidase assay in newborn Swiss mice, their mothers and adult controls. The mean number of SmIg + cells in adult mice was 45-8% and the mean number of antigenic sites per positive cells was 108,500. In newborn mice during the first 7 days of life, values for both parameters were low (24-25--28-5% and 38,000-45,773 respectively) and began to rise after the 10th day to reach adult levels between the ages of 2 and 3 weeks. A peak above adult levels for the mean number of sites per cell was observed on day 21 with a subsequent drop to adult levels on day 28. Post-partum females were found to have consistently fewer sites per positive cell (69,000-86,600) during the 14 days following delivery than their adult control counterparts, though the difference was not statistically significant.

Age Factors↗
PubMed1977

Investigation of a new parameter in chronic lymphocytic leukemia: the percentage of large peripheral lymphocytes determined by the Hemalog D. Prognostic significance.

The number of large peripheral lymphoid cells and the ratio of these large unstained cells to the total number of peripheral lymphocytes was determined by means of the Hemalog D in 57 patients with chronic lymphocytic leukemia (CLL) and in 100 control subjects. Although the absolute number of large unstained cells/mm3 is simply a reflection of peripheral lymphocytosis, the ratio large unstained cells to total lymphocyte count was shown to correlate with clinical staging. In control subjects, this ratio ranged from 3.2 per cent to 11¿per cent. In those with CLL it was less than 11.2 per cent in 43 patients and greater than 11.2 per cent in 14 patients. These 14 patients corresponded statistically to patients with advanced disease in our clinical staging system (stages III and IV). An increase in the large unstained cells to total lymphocyte ratio is therefore a statistical criterion of poor prognosis.

Humans↗