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71.
Time-to-event analysis is frequently used in medical research to investigate potential diseasemodifying treatments in neurodegenerative diseases. Potential treatment effects are generally evaluated using the logrank test, which has optimal power and sensitivity when the treatment effect (hazard ratio) is constant over time. However, there is generally no prior information as to how the hazard ratio for the event of interest actually evolves. In these cases, the logrank test is not necessarily the most appropriate to use. When the hazard ratio is expected to decrease or increase over time, alternative statistical tests such as the Fleming-Harrington test, provide a better sensitivity. An example of this comes from a large, five-year randomised, placebo-controlled prevention trial (GuidAge) in 2854 community-based subjects making spontaneous memory complaints to their family physicians, which evaluated whether treatment with EGb761® can modify the risk of developing AD. The primary outcome measure was the time to conversion from memory complaint to Alzheimer’s type dementia. Although there was no significant difference in the hazard function of conversion between the two treatment groups according to the preplanned logrank test, a significant treatment-by-time interaction for the incidence of AD was observed in a protocol-specified subgroup analysis, suggesting that the hazard ratio is not constant over time. For this reason, additional post hoc analyses were performed using the Fleming-Harrington test to evaluate whether there was a signal of a late effect of EGb761®. Applying the Fleming-Harrington test, the hazard function for conversion to dementia in the placebo group was significantly different from that in the EGb761® treatment group (p = 0.0054), suggesting a late effect of EGb761®. Since this was a post hoc analysis, no definitive conclusions can be drawn as to the effectiveness of the treatment. This post hoc analysis illustrates the interest of performing another randomised clinical trial of EGb761® explicitly testing the hypothesis of a late treatment effect, as well as of using of better adapted statistical approaches for long term preventive trials when it is expected that prevention cannot have an immediate effect but rather a delayed effect that increases over time.  相似文献   
72.
Various dermatologic manifestations are observed in the different lupus subsets. Lupus lesions are most frequently characterized by a dermoepidermal dermatitis. Other lesions, vascular or nonvascular, are essentially present in association with systemic lupus erythematosus. Acute, subacute and chronic lupus erythematosus are distinguishable according to their clinical aspects, pathological features and their evolution. Acute lesions are either localized to the midface or widespread. Subacute lesions may be annular or psoriasiform. Chronic lupus erythematosus includes localized or widespread discoid lupus, lupus tumidus, chilblain lupus and panniculitis. Therapy of cutaneous lupus is mainly based on antimalarials and avoidance of sun exposure. In refractory cutaneous lupus, no universal guidelines are available. Except for acrosyndromes and urticaria-like lesions, vascular lesions may be due to vasculitis or thrombosis. An accurate diagnosis is necessary, since therapeutic management is quite different in these two conditions. Nonvascular and nonlupus lesions are numerous and some of them require specific treatment, such as dapsone for bullous lupus.  相似文献   
73.
We address the relationship between reactive hemophagocytic syndrome (RHS), systemic lupus erythematosus (SLE) activity, and treatment in 4 female patients with SLE. Febrile pancytopenia was related to cytologically proven RHS in all patients. Followup was 45+/-7 months from RHS onset. No causal infection could be identified. Outcome could be classified as: (1) RHS onset during a SLE flare and complete efficacy of high dose steroids; (2) death despite therapy for concomitant severe RHS and active SLE; (3) severe RHS in inactive SLE under immunosuppressants, with remission after steroid tapering and cyclophosphamide withdrawal. Three patients were treated with intravenous IgG. We conclude that (1) when SLE is active, RHS should be considered a specific manifestation and treated with steroids; (2) RHS occurring in otherwise inactive SLE might be related to iatrogenic immunosuppression; (3) intravenous IgG treatment might be indicated in both situations.  相似文献   
74.
During the last decade, new biotherapies have been developed for the treatment of systemic autoimmune diseases, especially for systemic lupus erythematosus (SLE). These new approaches are based on a better understanding of the auto-immune response. Targets of these new treatments are all the steps of the immune response. These new therapies are: (1) "B lymphocyte (BL)" inhibitors such as anti-CD20 monoclonal antibody, anti-CD22 monoclonal antibody, BlyS antagonists, tolerogens of pathogenic-antibody secreting LB (LJP 394) and edratide; (2) "Inhibitors of the costimulation" between antigen-presenting cells and T lymphocyte (TL) like monoclonal anti-CD40 ligand antibody or CTLA-4-Ig (abatacept); (3) "Cytokine antagonists" inhibiting key cytokines of SLE: interleukin-10, interferon-alpha, interleukin-6 and TNF. These new therapies are currently under development in SLE.  相似文献   
75.
Sixty-three patients with high tumor mass multiple myeloma were treated with high-dose chemotherapy and total body irradiation supported by autologous blood stem cell transplantation. After high-dose therapy, they were monitored for a median of 44 months. Seven patients died early from toxicity. All the other patients, including those whose disease was resistant to previous therapies, showed a tumor mass reduction. At 6 months postengraftment, 40 (71%) of the surviving patients had minimal residual disease and 11 (20%) were in apparent complete remission. During follow-up, 25 out of the 63 (39%) patients relapsed and 16 of these died; 31 (49%) had a sustained remission. The median overall and event-free survival times after transplantation were 59 and 43 months, respectively. The initial serum beta 2-microglobulin value (> or < 2.8 mg/L) and length of previous therapy (> or < 6 courses of chemotherapy) were the only significant prognostic factors. In all surviving patients, blood stem cell autograft provided satisfactory and sustained haematopoietic reconstitution most often within 15 days. High dose chemoradiotherapy followed by autologous blood stem cell transplantation is thus an important therapeutic option for young patients with aggressive multiple myeloma.  相似文献   
76.
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.  相似文献   
77.
CONTEXT: Discordant data have been reported about the prevalence of hepatitis C virus (HCV) infection in patients with lymphoproliferative diseases and the putative role of HCV in lymphomagenesis. OBJECTIVE: To assess the prevalence of HCV infection in patients admitted to a hematology department in Paris, France. DESIGN: Prospective, controlled study. SETTING: University medical center. PATIENTS: 813 patients admitted to the Hematology department (164 B-cell non-Hodgkin's lymphoma, 34 Hodgkin's diseases, 107 chronic lymphocytic leukemia, 54 multiple myeloma, 12 Waldenstr?m's macroglobulinemia, 17 acute lymphoblastic leukemia, 6 hairy cell leukemia, 189 myeloproliferative diseases, 6 solid organ tumors, and 224 nonmalignant diseases) and 694 patients admitted to the Internal Medicine department (control group). MEASUREMENTS: All patients were tested for antibodies to HCV by a third-generation enzyme-linked immunosorbent assay. RESULTS: HCV antibodies were detected in 20 of 813 (2.46%) patients in Hematology including 11 of 394 (2.79%) patients with lymphoproliferative diseases, 3 of 164 (1.83%) B-cell non-Hodgkin's lymphoma, 2 of 107 (1.87%) chronic lymphocytic leukemia, 1 of 54 (1.85%) multiple myeloma, 1 of 189 (0.5%) myeloproliferative diseases, and 8 of 224 (3.57%) nonmalignant hematologic diseases. HCV antibodies were detected in 3 of 694 (0.43%) patients in the control group. HCV contamination preceded B-cell non-Hodgkin's lymphoma only in 2 of 3 HCV-positive patients. CONCLUSION: The prevalence of HCV infection was low (1.83%) in patients with B-cell non-Hodgkin lymphoma. HCV seems not to play a major role in the pathogenesis of B-cell lymphoma in France. Cofactors should be stressed to explain geographical discrepancies.  相似文献   
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INTRODUCTION: We report 2 cases of bilateral carotid thrombosis secondary to repeated attempts of strangulation. EXEGESIS: The first case was discovered in a 31-years-old woman who complained of psychiatric manifestations, memory loss and aphasia. Subsequently she developed hemiplegia which worsened under low dose aspirin. The second case occurred in a 41-years-old woman who presented with sudden hemiplegia and aphasia. Diagnosis of bilateral carotid thrombosis based on angiocomputerized tomography or angioRMI data which suggested dissection. Thrombosis location was similar: bilateral, symmetric, close to the carotid bifurcation. Both women had atherosclerosis risk factors: current smoking, use of estrogen containing pill, dyslipidemia and/or familial cardiovascular history. Search for thrombophilia was negative. Both women had been victims of intimate partner violence with repeated attempts of strangulation, but they were stopped 8 and 6 years before the diagnosis of carotid thrombosis. Several private interviews were necessary before knowing the exact cause. CONCLUSION: Symmetrical bilateral thrombosis of internal carotids near the bifurcation should lead to evoke repeated attempts of strangulation, even if there are arterial risk factors, and especially if the patient is a middle-aged female. The therapy is not codified but prolonged anticoagulation is generally prescribed.  相似文献   
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