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V Leblond

Publications and source records attributed to V Leblond.

124 records · Page 7Linked to original sources

Antithrombin III activity is not related to plasma homocysteine concentrations.

Arterial and venous thromboembolic events represent frequent and life-threatening complications in homocystinuric patients and are responsible for their early deaths. Reduced levels of antithrombin III activity in homocystinuric patients have recently been reported. So, high plasma L-homocysteine concentration could play a role in the low antithrombin III activity level. In the present study, we have studied the relationship between total plasma homocysteine and inhibitors of blood coagulation levels in 16 patients with malignancies who received bone marrow grafts. There were no correlations between homocysteine values and inhibitors of blood coagulation levels. So, while the defect in amino acid transsulfuration that is responsible for homocystinuria can directly affect the synthesis or activity of some clotting factors, homocysteine concentration is not responsible for this effect.

Adult↗

Allogeneic bone marrow transplantation in adults with Burkitt's lymphoma or acute lymphoblastic leukemia in first complete remission.

The prognosis of adults with Burkitt's lymphoma is very poor and depends on initial CNS and/or bone marrow involvement. We report results in nine adult patients with CNS (n = 9) and/or bone marrow involvement (n = 7) treated in first complete remission (CR) with allogeneic bone marrow transplantation (BMT). CNS treatment before the conditioning regimen consisted of cranial irradiation at 15 Gy (n = 8) and intrathecal chemotherapy (n = 9). The conditioning regimen included cyclophosphamide and total body irradiation (TBI) in a single dose. No postgraft CNS prophylaxis was administered. At the present time, seven patients are alive and disease-free at 18, 23, 44, 47, 54, 54, and 59 months. Two patients died at 14 and 7 months from transfusion-related acquired immune deficiency syndrome and bacterial septicemia and were disease-free at the time of their death. These preliminary results should encourage the use of BMT. A prospective randomized trial is warranted to further specify and investigate the advantages of allogeneic BMT versus conventional chemotherapy.

Adolescent↗

Diagnostic and prognostic significance of myelomonocytic cell surface antigens in acute myeloid leukaemia.

Thirty-six cases of acute myeloid leukaemia (AML) were tested with a large battery of monoclonal antibodies (moAbs) detecting surface markers normally expressed by myelomonocytic, T and B lymphoid, megakaryocytic and erythroid lineages. Differences in antigenic expression were observed among the various FAB subgroups: HLA-class II molecules were found in almost all AML cases but not in the promyelocytic subgroup (M3); CD14 and CD36 antigens were detected in monocytic leukaemias (M4 and M5); the CD34 moAb (MY10) recognizing an epitope described on myeloid stem cells was positive in 88% of the M1 and 80% of the M3 cases. By a multivariate analysis, only the CD14b (MY4) discriminated significantly between M1-M2 and M4-M5 subgroups. Using Cox's model to assess the prognostic importance of variables including immunophenotyping on survival, we undertook a one by one analysis and found that the presence of CD17 antigen predicted for a shorter survival (P = 0.03). In addition this marker appeared more significant than other clinical and biological parameters.

Adolescent↗

[Echocardiographic detection of adriamycin cardiotoxicity. Study of the relationship between the shortening fraction-constraint and the systolic shortening fraction-diameter of the left ventricle].

Cardiotoxicity is the main obstacle to the use of high-dosage adriamycin in chemotherapy. It is difficult to decide whether or not treatment should be continued when the cardiac function -- irrespective of the method by which it is evaluated -- is at the lower limit of normality. Some authors consider that chemotherapy can be pursued as long as the shortening fraction of the echocardiographic diameter remains within normal limits in relation to the end-systolic constraint. We have established the limits of normality of this relationship before chemotherapy in 53 patients with normal cardiovascular system. We conclude that the end-systolic constraint essentially depends on the end-systolic diameter, so that the results provided by the study of the shortening fraction end-systolic constraint relationship are qualitatively the same as those of the shortening fraction-end-systolic diameter relationship, which is much easier to obtain. It seems to us that the criteria of cardiotoxicity after administration of adriamycin 300 mg/m2 are: (1) shortening fraction lower than 25 p. 100; (2) ventricular dilatation (end-systolic diameter greater than 40 mm) without associated valve disease; (3) reduction of the shortening fraction (whatever its value) in relation to the end-systolic diameter by more than 2 standard deviations on the regression slope of the correlation; (4) more than 25 p. 100 reduction of the shortening fraction after administration of adriamycin 300 mg/m2, betraying a high sensitivity to the cardiotoxic effects of the drug. Such individual sensitivity, studied in 25 patients, seemed to vary widely from one subject to another and to be independent of the initial status.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Separation of mononuclear bone marrow cells using the Cobe 2997 blood cell separator.

In the present study, we report the results of our evaluation of the use of the continuous-flow cell separator Cobe 2997 to isolate from human bone marrow (BM) aspirates the mononuclear cell (MNC) fraction containing hematopoietic stem cells. This MNC concentrate is isolated in 15% of the original BM volume and contains 23% of the initial nucleated cells. It is enriched as concerns the BM MNC fraction (lymphocytes + monocytes recovery; 80%), whereas the contamination with granulocytes, red blood cells and platelets is reduced to 7.2, 1.5% and 41%, respectively, of the cells initially present in the BM suspensions. Furthermore, it is demonstrated that this MNC concentrate is highly enriched in granulocyte-macrophage-colony-forming cells (CFU-GM; recovery 83%). The method is simple, inexpensive, efficient and reproducible. It allows rapid processing of a large volume of BM without substantial loss of hematopoietic progenitor cells. It represents a valuable method of BM MNC concentration prior to further in vitro manipulations such as T cell or tumor cell depletion or cryopreservation.

Adolescent↗

Impact of T-cell depletion on outcome of allogeneic bone-marrow transplantation for standard-risk leukaemias.

71 leukaemic patients having HLA-matched bone-marrow transplants (BMT) were randomised to receive whole marrow (group A) or marrow depleted of T cells by treatment with monoclonal antibodies (anti CD4-CD5-CD8, group B; anti CD2-CD5-CD7, group C) plus complement. All patients received cyclophosphamide and total body irradiation before transplantation and cyclosporin after BMT. Marrow treatment removed 97% of T cells (median) in group B and 99% in group C. Although both serious and mild graft-versus-host disease (GVHD) were reduced in T-cell depleted patients, graft failure and relapse were increased. Graft failure was caused by GVHD and transplant complications in the controls and by rejection and relapse in the T-cell depleted groups; relapse-free survival did not differ between the groups. Without better control of host immunity and of the residual leukaemia T-cell depletion of the marrow, BMT should not be pursued in standard-risk patients.

Adolescent↗

T-cell depletion of bone marrow transplants: assessment of standard immunological methods of quantification.

The efficacy of bone marrow transplant (BMT) T-cell depletion for the prevention of acute graft-versus-host disease (GVHD) has been demonstrated in animal models and in clinical studies. The importance of T-cell depletion has to be evaluated with standardized methods suitable for routine purposes. We report herein an in vitro mature T-cell depletion using a cocktail of three monoclonal antibodies (CD2, CD5, and CD7) and baby rabbit complement in 38 histocompatibility leucocyte antigen (HLA)-identical BMT with no more than grade II acute GVHD. The T-cell depletion was quantified using three prestandardized immunological methods: immunofluorescence (IF) analysis, SRBC-rosetting assay, and PHA proliferation assay. A mean of 97.5% IF-assessed T-cell depletion was achieved in the 38 BMT. The immediate IF analysis using three distinct sets of anti-T-cell monoclonal antibodies allowed us to detect a mean of 1.2% residual T cells. The SRBC-rosetting assay was not useful to quantify T-cell depletion because no residual SRBC-rosette-forming cells could be detected in every case. The results of a prestandardized PHA-induced proliferation assay gave a mean 96.7% inhibition of proliferation, and they were correlated with the IF results although the IF threshold of detection was higher. From these data we conclude that our in vitro T-cell-depletion procedure is reproducible and that standardized simple immunological methods such as immediate immunofluorescence analysis and PHA proliferation assay provide good tools to assess a T-cell depletion effective in the prevention of acute GVHD.

Adolescent↗

Systemic infections with Trichosporon beigelii (cutaneum). Report of three new cases.

Three new cases of systemic mycosis due to Trichosporon cutaneum are reported and compared with the 23 previous reports. Two patients had acute leukemia and one patient had a lymphoblastic lymphoma. Blood cultures in two patients and cerebrospinal fluid in the third patient were positive for T. cutaneum. Only one patient recovered after antimycotic therapy and concomitant remission of his leukemia. At autopsy, the two other patients showed widespread infection with T. cutaneum. The authors conclude that diagnosis and management of such infection in the immunosuppressed host are difficult and the prognosis is poor.

Adult↗

[Disseminated aspergillosis in acute leukemia probably chemically-induced].

One case of invasive aspergillosis in patient with myeloblastic leukemia probably induced by chimiotherapy is reported. Aspergillosis is a severe infection in immunodepressed host with 70 to 80% of mortality. Early diagnosis can be often carried by broncho-alveolar lavage, route of entry is always pulmonary one. Rapidly established antimycotic treatment can avoid death. Laminar air flow rooms and air spores numeration allow prevention of this infection in the immunodepressed host.

Adult↗

AL cardiac amyloidosis and arterial thromboembolic events.

OBJECTIVE: To study the prevalence and characteristics of arterial thromboembolic events (ATEE) in the course of AL amyloidosis. METHODS: We report the case of a non-anticoagulated patient with AL amyloidosis restrictive cardiomyopathy who developed acute lower limb ischaemia. We then prospectively determined the prevalence of ATEE in all patients with AL amyloidosis who were evaluated in our institution for autologous peripheral stem cell transplantation. RESULTS: Nine out of 15 non-anticoagulated patients (60%) developed ATEE: ischaemic stroke (3), transient cerebral ischaemic attack (2), multiple peripheral arterial emboli (1), bilateral iliac artery thrombosis (1), bilateral optic nerve ischaemia (1), and mesenteric ischaemia (1). Haemodynamic stasis seemed to play a leading role in the pathophysiology of ATEE, in that all patients were on sinus rhythm and only one had a thrombus on echocardiography. We identified possible contributing factors to ATEE occurrence: concomitant treatments with oestroprogestogen regimen, thalidomide, granulocyte-macrophage colony-stimulating factor (GM-CSF) and extracellular volume disturbances related to the cytapheresis procedure. CONCLUSION: We report on an unusual frequency of ATEE among patients with AL cardiac amyloidosis. Despite its theoretical risks, anticoagulation should be discussed for patients with amyloid cardiomyopathy.

Aged↗