Biomedical subjects
Publications and source records attributed to P Bourquelot.
Microsurgery gives much better immediate and long term results than classical surgery for the creation of direct arteriovenous fistulae, the best chronic access to blood in children.
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Central venous stenosis is a complication of central vein catheter insertion through the internal jugular or the femoral vein in haemodialysed patients with non-functioning arteriovenous angio-access. The frequent complication is important limb swelling after subsequent creation of upstream arteriovenous fistula or graft. Closure of the fistula may be necessary, especially if creation of a new access is possible on the opposite limb. Surgical conservative treatment may be indicated. Percutaneous transluminal angioplasty is used first with good short-term results. Prevention of central venous stenosis by infrequent use of central venous catheter is of the utmost importance.
PURPOSE: Posttransplant lymphoproliferative diseases (PTLDs) represent a group of potentially lethal lymphoid proliferations that may complicate the course of solid organ transplantation. Although early-onset PTLDs frequently have a favorable outcome, late-onset PTLDs behave more alike aggressive lymphoma. We report a monocentric retrospective study that focused on PTLDs occurring later than 1 year after kidney transplantation (very late-onset PTLDs) to define their incidence, clinical presentation, pathologic features, and outcome. We particularly emphasized the follow-up of patients treated with conventional chemotherapy. PATIENTS AND METHODS: The medical histories of all patients who developed very late-onset PTLD in our institution were reviewed, and diagnostic biopsy materials were retrospectively studied. RESULTS: Very late-onset PTLDs were diagnosed in 16 (1.1%) of 1,421 patients. Mean (+/- SD) time to tumor onset was 103.93 +/- 70.88 months. Most tumors were Epstein-Barr virus-related monomorphic large-cell PTLDs of B phenotype. Ten patients received conventional chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisone regimen). Two of them died within 2 months, two achieved partial remission, and six achieved definitive complete remission. Overall median survival time was 13 months and rose to 27 months in the treated group. The main cause of mortality was sepsis. None of the treated patients experienced rejection despite withdrawal of immunosuppressive treatment. CONCLUSION: Despite characteristics of aggressive lymphoma, very late-onset PTLDs after renal transplantation may respond to conventional chemotherapy. However, because a high rate of infectious complications occurred, new therapeutic strategies, such as combinations of anti-CD20 monoclonal antibodies and lower doses of chemotherapy, are warranted.
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Hand ischemic steal syndrome due to a forearm arteriovenous fistula is a rare occurrence. We report here a case in which we applied a new diagnostic method to assess the efficacy of distal radial ligation to treat this syndrome. A favorable comparison of distal radial artery pressure measurements before and after temporary occlusion of the artery with a balloon catheter indicated that perfusion of the hand would be dramatically improved after surgical artery ligation.
Expression of NG2 has been reported in the majority of paediatric acute leukaemia (AL) cases with MLL rearrangement. We demonstrated 7. 1 positivity in 2/3 paediatric and 4/11 adult MLL rearranged acute myeloid leukaemia (AML) but in 0/28 adult AML without MLL rearrangement, thus extending the 100% specificity to adult cases. Positivity correlated with stage of maturation arrest since it was found in 0/6 immature AML but in 6/8 monoblastic cases. These data demonstrate that, if NG2 expression in AL is the (in)direct result of MLL rearrangement, such activation is restricted to a monoblastic population in AML. They also have practical implications for NG2 diagnostic screening strategies.
Appropriate staging and evaluation of residual disease is critical to improving the treatment of patients with lymphoma. The specific expression of homing receptors may determine the preferential dissemination pattern of tumoral cells. We investigated the expression of the mucosal homing receptor alpha4beta7 on tumoral cells from peripheral lymph node in patients with newly diagnosed mantle cell lymphoma (MCL) to check whether it is associated with gastrointestinal involvement. Expression of the alpha4beta1 integrin and the peripheral lymph node addressin CD62L were also examined. Thirteen MCL patients presenting with peripheral lymphadenopathy were studied. Expression of the mucosal homing receptor integrin alpha4beta7 by peripheral lymph node lymphoma cells was found to be frequent (5/13) and associated with gastrointestinal involvement (5/7). In contrast, lymphoma cells from patients without gastrointestinal involvement did not express alpha4beta7 (6/6) (P = 0.03). These data suggest that alpha4beta7 integrin is expressed by a subset of MCLs and that its expression may predict digestive tract involvement in MCL, furnishing a basis for recognizing two distinct clinical and phenotypic forms, ie, "digestive homing (or digestive primitive)" versus "peripheral" MCL. Further studies on more patients will be needed to understand the impact of biological differences on the prognosis of these two clinical forms.
In a multicentre trial involving 20 transplant centres from 10 countries haematopoietic stem cells were obtained either from the bone marrow of 33 sibling donors or from the peripheral blood of 33 such donors after administration of filgrastim (10 microg/kg/day). The haematopoietic stem cells were infused into their HLA-identical recipients suffering from acute leukaemias in remission or chronic myeloid leukaemia in chronic phase. PBPC donors tolerated filgrastim administration and leukapheresis well with the most frequent side-effects being musculoskeletal pain, headache, and mild increases of LDH, AP, Gamma-GT or SGPT. Pain and haematoma at the harvest site and mild anaemia were the most frequent complaints of BM donors. Severe or life-threatening complications were not seen with any type of harvest procedure. Time to platelet recovery greater than 20 x 10(9)/l was 15 days (95% confidence interval (CI) 13-16 days) in the PBPCT group and 19 days (CI 16-25) in the BMT group. Time to neutrophil recovery greater than 0.5 x 10(9)/l was 14 days (CI 12-15 days) in the PBPCT group as compared to 15 days (CI 15-16 days) in the BMT group. The numbers of platelet transfusions administered to PBPCT and BMT patients were 12 (range: 1-28) and 10 (range: 3-39), respectively. Sixteen patients (48%) transplanted with bone marrow and 18 patients (54%) transplanted with PBPC developed acute GVHD of grades II-IV; acute GVHD of grades III or IV developed in six (18%) and seven (21%) patients, respectively. Kaplan-Meier plots for transplant-related mortality until day 100 and leukaemia-free survival at a median of 400 days after BMT or PBPCT showed no significant differences. Administration of filgrastim and leukapheresis in normal donors were feasible and well tolerated. The number of days with restricted activity and of nights spent in hospital was lower in donors of PBPC. Transplantation of PBPC to HLA-identical siblings with early leukaemia resulted in earlier platelet engraftment. The incidence of moderate to severe acute GVHD, transplant-related mortality, and leukaemia-free survival did not show striking differences. Further investigation of allogeneic PBPCT as a substitute for allogeneic BMT is warranted.
We retrospectively investigated the feasibility and the toxicity of autologous stem cell transplantation (ASCT) in 21 cases of systemic amyloidosis (AL). The conditioning regimens consisted of high-dose melphalan (HDM) alone (n = 18) or in combination with 12 Gy total body irradiation (n = 3). Toxic death rate was high: 9/21 patients (43%) died within the first month following ASCT, and 10/12 surviving patients achieved a response. With a median follow-up of 14 months, the OS and the EFS rates at 4 years were 57.1% (+/-10.8) and 29.9% (+/-14.5) respectively for the whole group. The major prognostic factor for both response and survival was the number of clinical manifestations at the time of ASCT, of the following five criteria, i.e. creatinine clearance < 30 ml/min, nephrotic syndrome with urinary protein excretion > 3000 mg/24 h, congestive heart failure, neuropathy, or hepatomegaly associated with alkaline phosphatase level > 200 IU/l. For patients presenting with two or more clinical manifestations the 4-year OS and EFS were both 11.1% compared with 91.7% and 46.3% respectively in patients with fewer than two clinical manifestations at the time of ACST. We conclude that ASCT is feasible in AL in a subset of patients with fewer than two clinical manifestations at the time of ASCT. Given the severe extra-haematological toxicity, ASCT should not be considered in other cases.
The TAL1 gene is disrupted by translocation or deletion (tal(d)) in up to 30% of T-cell acute lymphoblastic leukaemia (T-ALL), leading to aberrant transcriptional activation, as a SIL-TAL1 fused transcript in tal(d). It has been suggested that TAL1 transcription occurs in approximately 50% of a T-ALLs without apparent rearrangement. SIL-TAL1 was positive in 15/60 (25%) of T-ALL, whereas wild-type TAL1 transcripts were detected in all 13 SIL-TAL1 and in 19/43 (44%) T-ALL without SIL-TAL1. To investigate the cellular origin of TAL1 we exploited the fact that GATA1 and TAL1 are co-ordinately expressed in non-lymphoid haemopoietic cells, whereas only the latter is found in T-ALL. GATA1 was detected in 10/23 (43%) TAL1-negative T-ALLs but in 17/19 (89%) 'unexplained' TAL1-positive cases, suggesting a common non-lymphoid cellular origin. Immunocytochemical analysis with a TAL1-specific monoclonal antibody showed nuclear expression in the blasts of 10/34 (29%) cases, including 8/10 SIL-TAL1+ and two RT-PCR TAL1+, SIL-TAL1- cases. In the remaining cases TAL1 expression was restricted to a minor population (< 5%) of larger, strongly TAL1-positive cells which comprised erythroid cells, CD34+ CD3- precursors and an unidentified TAL1+ CD45- population which morphologically resembled monocytes/macrophages. We therefore suggest that appropriate diagnostic evaluation of T-ALL should include molecular detection of SIL-TAL1 transcripts and in situ immunocytochemical detection of TAL1 protein expression by leukaemic blasts. This approach will enable accurate analysis of the prognostic significance of TAL1 deregulation in T-ALL.
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The rapid detection of chromosome band 8q24 rearrangements, including classical translocations involving MYC and variant 3' translocations, is important for the accurate diagnosis and appropriate treatment of lymphoid malignancies. We have identified and characterized a CEPH YAC, 934e1, which extends from at least 190 kbp upstream to over 280 kbp downstream to MYC, allowing detection of classical t(8; 14)(q24;q32) and variant t(8;22)(q24;q11) and t(8;14)(q24;q11), extending distal to PVT1 and therefore, by extrapolation, to BVR1. This YAC also allowed clarification of complex chromosome 8 abnormalities and the identification of translocations in interphase nuclei. A second CEPH YAC, 904c3, previously shown to contain the PVT1 locus but not MYC, allowed distinction between translocations occurring centromeric and telomeric to MYC. Use of the 934e1 YAC will aid classification of a variety of lymphoid proliferations and further characterization of rearranged cases with the 904c3 YAC will simplify mapping of their diverse breakpoints.
AL amyloidosis is a rare disease. Its diagnosis is based on histopathology. It is always secondary to light chain, only rarely heavy chain, synthesis of monoclonal immunoglobulin, associated or not with tumoural proliferation (myeloma, Waldenström's macroglobulinaemia). Its pathophysiology has not been elucidated, but recent progress provided by biochemical and molecular biology studies has provided some data on the structural anomalies responsible for the formation of amyloid fibrils. As in AA amyloidosis, the clinical picture is heterogeneous and mainly depends on the degree and extent of the lesions. Prognosis remains poor and is influenced by the degree of cardiac, gastrointestinal, neurologic and renal involvement, but also by the presence of absence of underlying hemopathy, and particularly of myeloma. Treatment is still essentially symptomatic, but recent progress points to hope of effective treatment modalities aiming at reducing or eliminating the clone producing the immunoglobulin, or inhibiting the formation or amyloid fibrils.
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