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V Deneys

Publications and source records attributed to V Deneys.

At least 19 recordsLinked to original sources
PubMed2006

[Venous malformations and coagulopathy].

Activation of the coagulation process is frequently encountered in patients with venous vascular malformations and results in the local formation of clots and the consumption of components of the coagulation process (platelets, clotting factors). This activation accounts for multiple biological abnormalities such as the elevation of the D-dimers, reduction of fibrinogen and platelets count and less frequently a local intravascular coagulation (LIC). This process seems to be responsible for the local painful symptoms. In case of LIC, bleeding complications may be observed. Therapeutically, antithrombotic treatment with low-molecular weight heparin can improve the local coagulopathy with beneficial effects on blood tests disturbances, pain and bleeding tendency.

Blood Coagulation Disorders↗
PubMed2006

Inadvertent anticoagulation of a haemophiliac child with routine line flushing.

We report the case of a 3-year-old boy with severe haemophilia A presenting with recurrent haemarthroses despite daily infusions of factor VIII delivered through a central venous access device (CVAD). Regular rinsing of the CVAD with heparin, according to a standard protocol, resulted in systemic anticoagulation, as demonstrated by prolonged thrombin time and therapeutic anti-Xa levels. The bleeding symptoms resolved after replacing heparin with a normal saline solution. This case illustrates that heparin administered to maintain CVAD patency should be used with caution in young haemophiliacs. Prolonged thrombin time should alert the physician to this possible CVAD complication.

Anticoagulants↗
PubMed2004

Coexistence of BCL1/CCND1 and CMYC aberrations in blastoid mantle cell lymphoma: a rare finding associated with very poor outcome.

A patient with mantle cell lymphoma (MCL) of the pleomorphic blastoid subtype is reported. The disease was clinically aggressive and refractory to chemotherapy, and the patient survived only 2 months. Cytogenetically, a t(11;19;14)(q13;q13;q32) was found. Fluorescent in situ hybridization (FISH) and molecular analyses demonstrated involvement of the BCL1/CCND1 locus in a three-way translocation. In addition, subclonal abnormalities of the region 8q24 manifested either as a t(8;22)(q24;q11)/CMYC rearrangement or trisomy 8 were identified. The pathogenetic impact of this very uncommon association of BCL1/CCND1 and CMYC rearrangements in MCL is discussed and the literature is reviewed.

Aged↗
PubMed2004

Tracking the follicular lymphoma cells in flow cytometry: characterisation of a new useful antibody combination.

OBJECTIVES: Follicular lymphoma (FL) is the most common adult non-Hodgkin's lymphoma. Diagnosis is based on morphology and can be confirmed by cytogenetic, flow cytometry (FCM) or molecular studies. Despite all these complementary approaches, diagnosis sometimes remains difficult. The purpose of the present work was to characterise the expression of new specific follicular cells markers which allows us to target specifically the abnormal FL cell population in FCM. METHODS: A total of 153 samples from healthy subjects and from patients with chronic B-cell lymphoproliferative disorders were analysed by FCM in the same conditions for purpose of comparison. RESULTS: We showed that CD44 is weakly expressed in FL cells compared with peripheral blood mononuclear cell from normal blood donors and others cells from B lymphoproliferative diseases. We nevertheless observed bone marrow samples where some immature B-cell population express CD44 with lower fluorescence intensity. Therefore, we developed a double antibody combination, using CD44 and CD38, which allowed us to separate the normal immature cells from the pathological population using FCM. CONCLUSION: This new phenotypic approach offers an accurate (sensitivity and specificity of 93% and 96%, respectively), fast and low sample consuming method for the diagnosis of FL.

ADP-ribosyl Cyclase↗
PubMed2004

[Hemostasis and blood coagulation revisited: mechanisms and therapeutic implications].

The number of oral anti-thrombotic agents is steadily expanding. Major advances have recently been made in the understanding of haemostasis and blood coagulation processes. This paper reviews the mechanisms of haemostasis and thrombosis and the molecules used for the treatment of arterial and venous thrombotic disorders with a special emphasis on recently introduced agents (Clopidogrel, Pentasaccharide, Melagatran).

Anticoagulants↗
PubMed2004

[Coagulation factors and hemostatic agents].

A large variety of therapeutic agents are available to prevent or treat hemorrhagic events. An etiologic focusing is essential to permit a rational use of these drugs. Some medications are cheap, others are very expensive, and the clinician has to evaluate the cost-effectiveness of his prescription in each situation.

Antifibrinolytic Agents↗
PubMed2003

Immunological classification of acute myeloblastic leukemias: relevance to patient outcome.

Immunophenotyping is a major tool to assign acute leukemia blast cells to the myeloid lineage. However, because of the large heterogeneity of myeloid-related lineages, no clinically relevant immunological classification of acute myeloblastic leukemia (AML) has been devised so far. To attempt at formulating such a classification, we analyzed the pattern of expression of selected antigens, on blast cells collected at AML diagnosis. Patients were eligible if they had a first diagnosis of de novo AML and a sufficient number of blast cells for proper immunophenotyping. The relative expression of CD7, CD13, CD14, CD15, CD33, CD34, CD35, CD36, CD65, CD117, and HLA-DR were analyzed by cytometry in a test series of 176 consecutive AML cases. Statistical tools of clusterization allowed to remove antigens with overlapping distribution, leading us to propose an AML classification that was validated in a second AML cohort of 733 patients. We identified five AML subsets (MA to ME) based on the expression of seven antigens within four groups (CD13/CD33/CD117, CD7, CD35/CD36, CD15).-MA and MB-AML have exclusively myeloid features with seldom extramedullary disease and rare expression of lymphoid antigens. No cases of acute promyelocytic leukemia (APL) were observed within MB AML. MC AML have either myeloid or erythroblastic features. MD AML have more frequently high WBC counts than other subsets, which were related to the expression of CD35/CD36 and CD14 and to monoblastic differentiation. ME AML lack CD13, CD33, and CD117 but display signs of terminal myeloid differentiation. Specific independent prognostic factors were related to poor overall survival in each immunological subset: CD34+ (P<3 x 10(-4)) in MA AML, CD7+ in MB AML, non-APL cases (P<0.03) in MC AML, CD34+ (P<0.002) and CD14+ (P<0.03) in MD AML, CD14+ in ME AML (P<0.01). The inclusion of seven key markers in the immunophenotyping of AML allows a stratification into clinically relevant subsets with individual prognostic factors, which should be considered to define high-risk AML populations.

Adolescent↗
PubMed2001

Reference values for peripheral blood B-lymphocyte subpopulations: a basis for multiparametric immunophenotyping of abnormal lymphocytes.

BACKGROUND AND OBJECTIVES: Immunophenotyping has become a useful tool for the differential diagnosis of chronic B-cell lymphoproliferative disorders. The aim of this work was to determine reference values of normal B-cell subpopulations. MATERIAL AND METHODS: Blood samples from 38 healthy volunteers were analyzed by multidimensional flow cytometry, using a panel of directly conjugated antibodies. Results were expressed as percent of positive B cells and as median fluorescence intensity, an indirect assessment of the expression level. RESULTS: CD20, CD22, CD24, CD40, CD79a, CD79b, FMC7, CD11a, CD18, CD44 were positive in the whole B cell population, whereas CD10, CD86, CD103, CD154 and FasL were almost absent from the B-lymphocyte population. 75% were IgD positive. The kappa/lambda ratio was 1.5. CD5, CD23, CD25, CD38, CD43, CD54, CD62L, CD80 and CD95 were positive in different B-cell subpopulations. The utility of all these markers in the differential diagnosis of chronic B-cell lymphoproliferative disorders is discussed. CONCLUSION: In order to interpret a pathological immunophenotype, it is necessary to refer to quantitative and qualitative values of normal B-cell subpopulations.

Adult↗
PubMed2001

Expression of HLA-DR, CAM and co-stimulatory molecules on cord blood monocytes.

Umbilical cord blood (CB) transplantations are associated with a lower risk of severe graft-versus-host disease (GVHD) compared to BMT. GVHD is an immune reaction that involves interaction between cell surface molecules resulting in cell activation and release of many cytokines. Monocytes are known to be an important source of cell adhesion (CAM) and co-stimulatory molecules which play a crucial role in the efficient activation of T and B cells. We analyzed the phenotype of CB monocytes in the presence or absence of an inflammatory signal (rIFN-gamma) and compared them to adult blood (AB); the expression of HLA-DR and 17 different markers (CD11a, CD11b, CD11c, CD18, CD29, CD40, CD44, CD49a, CD49d, CD49e, CD49f, CD54, CD58, CD62L, CD80, CD86 and CD102) was measured by flow cytometry. Statistical analysis showed that, compared to AB, CB monocytes did not express CD11b, CD11c, CD49d and after stimulation with rIFNgamma, they lost the expression of CD58 and CD102, whereas CD80 and CD86 expression was induced. The analysis of fluorescence intensity (MFI) revealed that CB monocytes expressed some CAM (CD29, CD54, CD102) with a lower intensity than AB monocytes except CD44. In conclusion, absence and reduced expression of some markers argue for a different phenotypic profile of CB monocytes compared to AB monocytes, which might partly contribute to their impaired immune response and to the low incidence of GVHD observed after CB transplantations. However, CB monocytes expressed CD80 and CD86 co-stimulatory molecules, but this expression did not prove a normal co-stimulatory function.

Adult↗
PubMed2001

Intracellular cytokine profile of cord and adult blood monocytes.

Cord blood (CB) transplantations are associated with low graft-versus-host disease (GVHD). The pathophysiology of GVHD involves interaction and activation of different cell types, as lymphocytes and monocytes, and results in a cascade of cytokine production. After antigen or mitogen stimulation, CB monocytes release lower levels of cytokines than adult blood (AB) monocytes. In this study, the detection of intracellular IL-1 beta and TNF-alpha produced by monocytes was evaluated in response to tuberculin PPD to investigate whether the reduced capacity of CB monocytes to secrete cytokines could be related to an impaired functional activity and to a particular phenotypic profile. Results showed that the percentage of CD64(+)monocytes producing intracellular IL-1 beta and TNF-alpha was significantly lower in CB and that the phenotypic profile of CB monocytes producing these cytokine (CD64(+)CD14(+)) was different to that of AB monocytes (CD64(+)CD14(+), CD64(+)CD33(+) and CD64(+) CD45RO(+)). These results suggest that the lower capacity of CB monocyte populations to produce IL-1 beta and TNF-alpha might be due to a functional immaturity of CB monocytes at the cellular level as reflected by the different phenotypic profile of CB monocytes.

Cytokines↗
PubMed2001

Atypical lymphocytic leukemia and mantle cell lymphoma immunologically very close: flow cytometric distinction by the use of CD20 and CD54 expression.

Integration of morphological and immunophenotypic data is critical in achieving diagnosis accuracy and minimising interobserver interpretative discrepancies. The aim of this work was to compare the immunophenotype and the morphology of chronic lymphocytic leukaemia and mantle cell lymphoma, to help in the differential diagnosis of CD5 positive monoclonal B cells. Frozen/thawed samples from 91 patients were analysed retrospectively. Fresh samples from 17 mixed/atypical CLL and 13 MCL were tested to corroborate the results. Markers were analysed as percentage (%) of positive B lymphocyte subpopulation, and in terms of median fluorescence intensity (MFI). Matutes's CLL score clearly allowed distinguishing between classical CLL on the one hand, and atypical CLL and MCL on the other hand. The percentage of CD54-positive cells and the median fluorescence intensity of CD20 and CD54 were the only parameters which were significantly higher in MCL than in atypical CLL (P < 0.05), allowing an immunological distinction between these two entities. Nevertheless, due to a quenching problem when using CD20 and CD54 together, and because CD18 showed a statistically different expression between classical and atypical CLL, the combination of CD18/CD54 has been preferred and showed a different pattern in the three entities. Immunophenotyping could be helpful in the differential diagnosis of CD5-positive B cell chronic lymphoproliferative disorders with atypical features that do not fit exactly into any of the morphologic proposed groups.

Adult↗
PubMed2000

The value of interphase fluorescence in situ hybridization for the detection of translocation t(12;21) in childhood acute lymphoblastic leukemia.

Translocation t(12;21)(p13;q22) is the most frequent cytogenetic abnormality in childhood acute lymphoblastic leukemia (ALL) and is generally associated with favorable prognosis. In this report, we assessed the value of dual-color interphase fluorescence in situ hybridization (FISH) for the detection of t(12;21). Fifty-three patients were screened for ETV6/CBFA2 fusion by means of FISH, using two cosmid probes mapped on ETV6 and on CBFA2, respectively. The cut-off value (mean + three standard deviations) for positivity established on control patients was 9.3%. A comparison between FISH and molecular methods [reverse-transcriptase polymerase chain reaction/Southern blot (RT-PCR/SB)] was possible in 52 patients: 34 of 52 (65.4%) showed negative results with both approaches, and 13 of 52 (25%) were positive; 5 of 52 (9.6%) showed discrepancies: four patients who were positive using RT-PCR/SB were negative using FISH. Conversely, one patient negative when using RT-PCR/SB was positive with FISH. Further investigations on this patients, cytogenetically characterized by add(12p), showed an atypical breakpoint on ETV6, located 5' to the common breakpoint. Compared with RT-PCR and SB, dual-color interphase FISH with the cosmid probe set proved to be highly specific but showed limited sensitivity.

Blotting, Southern↗
PubMed1999

Impact of cryopreservation on B cell chronic lymphocytic leukaemia phenotype.

BACKGROUND AND OBJECTIVES: Freezing is a practical approach for cell preservation for retrospective studies. The aim of this work was to check the cryopreservation impact on B cell chronic lymphocytic leukaemia phenotype. MATERIAL AND METHODS: Blood samples from 15 CLL patients were analyzed freshly and after freezing at -196 degrees C, without separation, and thawing. Results were compared by Student's paired t-test. RESULTS: The phenotype of fresh CLL cells was as follows: CD19+, CD5+, faint CD20, CD23+/-, weak CD22 and sIg, CD37+, HLA-DR+, FMC7-. After cryopreservation, the percentage of CD5 and CD23 positive cells decreased, whereas HLA-DR positive cells increased moderately. The CLL Matutes's score was modified in 6 cases out of 15 (40%). CONCLUSION: Cryopreservation modifies B cell chronic lymphocytic leukaemia phenotype, by decreasing CD5 and CD23 expression.

Adult↗
PubMed1999

Potentiation of antitumor effects of cyclophosphamide derivatives in B-chronic lymphocytic leukemia cells by 2-chloro-2'-deoxyadenosine.

Because 2-chloro-2'-deoxyadenosine (CdA) is active in B-chronic lymphocytic leukemia (B-CLL), and may interfere with DNA repair, we investigated the potentiating effect of CdA on the cytotoxicity induced in vitro in B-CLL lymphocytes by cyclophosphamide (CP) derivatives, which induce DNA damage by DNA cross-linking. Exposure to CdA at clinically achievable concentrations for 2 h, followed by mafosfamide (MAF) or 4-hydroxycyclophosphamide (4HC) for 22 h, resulted in synergistic cytotoxicity in the majority of B-CLL samples tested. Synergy between CdA and MAF was observed in cell samples of sensitive/untreated patients, as well as in cells of resistant/pretreated patients, particularly at the highest concentrations of MAF. In the cells treated with CdA and MAF, we observed loss in ATP and hallmarks of apoptosis, as evidenced by cellular morphology and high molecular weight DNA fragmentation. The synergy could be explained neither by an influence of MAF on the phosphorylation of CdA, nor by an increase in the incorporation of CdA into DNA in the presence of MAF. The in vitro synergy between CdA and CP derivatives provides a rationale for the use of this association in B-CLL patients.

Antineoplastic Agents, Alkylating↗
PubMed1999

Pretransplant helper T-lymphocyte determination in bone marrow donors: acute graft-versus-host disease prediction and relation with long-term survival.

Helper T-lymphocyte precursor (HTLp) frequency from 19 allogeneic bone marrow donors was tested to detect weak antigenic differences with the recipient, and then compared to the outcome. HTLp frequency was estimated in limiting dilution cultures, and HLA-DR and CD 80 expression by stimulating cells was measured by flow cytometry. 12/19 patients experienced acute graft-versus-host disease (aGVHD) grade II-IV. A good correlation was found between high pretransplant HTLp frequency and grade II-IV aGVHD (median: 1/55848 PBMNC for II-IV GVHD versus 1/184346 for 0-I GVHD; P = 0.008). Sensitivity was 82%, specificity 63%, negative predictive value 71% and positive predictive value 75%. Long-term survivors also had a lower HTLp median frequency (1/143354) when compared with patients who died as a result of the transplant procedure (1/22100, P < 0.001). No correlation was found between HTLp frequency and HLA-DR or CD80 expression by patient's cells. We conclude that HTLp frequency estimation can predict, although poorly, acute GVHD risk and long-term survival.

Adult↗