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51.
Twenty-five patients with at least 3 of 1982 ARA criteria of SLE but without the ANA, were compared with 91 patients with 4 or more of the ARA criteria of lupus with positive ANA. The ANA-negative group was characterised by the low incidence of skin involvement, serous effusions and alopecia, and a relatively high incidence of thrombocytopaenia and venous and arterial thrombosis. Three types of antiphospholipid antibodies were looked for: the VDRL, antiprothrombinase and anticardiolipin antibodies by an immuno-enzymatic method. The VDRL was the only antibody which was significantly commoner in the ANA-negative group. Statistical studies showed that the three methods of demonstrating antiphospholipid antibodies detected crossed but not identical specificities. In the ANA-positive group only the antiprothrombinase was associated with a high incidence of venous thrombosis and stroke. In the ANA-negative group, only the anticardiolipin antibodies were associated with a high incidence of arterial or venous thrombosis. Two subgroups may be identified in the group of ANA-negative lupus patients: firstly, those with high anticardiolipin antibody titres with a high incidence of thrombotic and haematological complications, and, secondly, patients with low anticardiolipin antibody levels with a high incidence of cutaneous involvement, serous effusions and Raynaud's phenomenon.  相似文献   
52.
Two B-cell lines, 2F7 and 10C9, were established by single cell cloning from biopsies obtained from two acquired immune deficiency syndrome patients with Burkitt's lymphoma. Representation of the original tumors was verified by demonstration of (1) identical biallelic rearrangement of Ig genes for 2F7 and (2) shared idiotype for 10C9. Both cell lines displayed cell-surface Ig and secreted Ig (IgM lambda for 2F7, IgM kappa for 10C9). IgMs from both cell lines immunoprecipitated actin; in addition, 2F7 IgM lambda immunoprecipitated recombinant human immunodeficiency virus type 1 (HIV-1) gp 160. 2F7 IgM lambda did not react with other autoantigens (double-stranded and single-stranded DNA, actin, bovine serum albumin, IgG), whereas 10C9 IgM kappa reacted with human IgG. The 2F7 IgM heavy-chain variable region (VH) showed a 95% nucleotide homology with a previously sequenced VHIII germline gene, hv3019b9, whereas the 10C9 IgM VH showed a 95% homology with a previously sequenced VHIV germline gene, VH4.21. Use of minimally modified VH genes and demonstration of reactivity with chronically present antigens (ie, actin, HIV-1 gp 160, or human IgG) suggests that B cells in HIV-1-infected individuals proliferating in response to chronic antigenic stimulation may be at increased risk for lymphomagenesis.  相似文献   
53.
We have investigated the role of platelets in regulating the hemostatic and vasomotor properties of vascular smooth muscle. Experiments were performed to examine the effect of the releasate from activated platelets on the production of nitric oxide from interleukin-1 beta (IL- 1 beta)-treated cultured rat aortic smooth muscle cells. Treatment of vascular smooth muscle cells with IL-1 beta resulted in significant accumulation of nitrite in the culture media and in marked elevation of intracellular cyclic guanosine monophosphate (GMP) levels. The releasate from collagen-aggregated platelets blocked the IL-1 beta- mediated production of nitrite and the accumulation of cyclic GMP in smooth muscle cells in a platelet number-dependent manner. In functional assays, the perfusates from columns containing IL-1 beta- treated smooth muscle cells relaxed detector blood vessels without endothelium and the addition of IL-1 beta-treated smooth muscle cells to suspensions of platelets inhibited their thrombin-induced aggregation. The simultaneous treatment of smooth muscle cells with IL- 1 beta and the platelet releasate abolished both the vasorelaxing activities of the perfusates and the inhibition of platelet aggregation. Platelet releasates treated with a neutralizing antibody to platelet-derived growth factor (PDGF) failed to block IL-1 beta- induced nitric oxide production by the smooth muscle cells, as measured by both biochemical and functional assays. The platelet releasate from a patient with gray platelet syndrome likewise failed to block IL-1 beta-induced nitrite release by smooth muscle cells. These results demonstrate that platelets downregulate the production of nitric oxide by IL-1 beta-treated vascular smooth muscle cells through the release of PDGF. This effect may represent a novel mechanism by which platelets regulate vasomotor tone and thrombus formation at sites of vascular injury.  相似文献   
54.
In two previous studies, we observed that recombinant human interleukin- 3 (IL-3) induced an increase in marrow burst-forming unit-erythroid- derived colonies in vitro in some patients with Diamond-Blackfan anemia (DBA). To determine whether a similar erythropoietic response could be induced in vivo, we treated 13 patients with DBA (aged 4 to 19 years) with two preparations of IL-3. All patients had absent absolute reticulocyte counts and markedly reduced to absent recognizable bone marrow erythroid elements; patients with circulating reticulocytes in the previous 12 months were excluded from study. All patients except 1 had failed steroid therapy and had been transfusion-dependent since infancy; 1 patient was maintained on high-dose prednisone at the time of enrollment. On the first arm of the study, IL-3 (Immunex Corp, Seattle, WA) was administered subcutaneously using a dose escalation regimen of 125 to 500 micrograms/m2/day in divided dosage at 12-hour intervals, coadministered with 1.5 mg/kg/d of oral ferrous sulphate. Of the 13 patients that entered the trial, 4 stopped prematurely because of adverse side effects. In the other 9 evaluable cases, reticulocytes increased transiently in 1 patient from 0 to 65 x 10(9)/L after 35 days of IL-3 therapy at 250 micrograms/m2, but transfusion dependency persisted. One transient peak in absolute reticulocyte count was noted in 6 other patients, but no erythroid response was observed after completion of a full course of IL-3. Oral prednisone at 0.5 mg/kg/d was then coadministered with IL-3 at 500 micrograms/m2 to 5 of the patients without effect, and treatment was stopped. In 2 patients, a second preparation of IL-3 (Sandoz Canada Inc, Dorval, Quebec, Canada) was initiated in a dose escalation regimen of 2.5 to 10 micrograms/kg and was coadministered with ferrous sulphate. No erythroid response was observed in either patient, and in one of the two, alternate-day subcutaneous recombinant erythropoietin at 300 U/kg was administered for 3 weeks in combination with daily IL-3 at 10 micrograms/kg, but no increased erythropoiesis was seen. Significant increases in white blood cell and eosinophil counts during administration of both preparations of IL-3 were observed in all patients. These data show that the response of DBA patients to IL-3 in vivo is heterogeneous and cannot be predicted from in vitro studies. The absence of a corrective effect of IL-3 in these patients with DBA indicates that a deficiency of the cytokine is not central in the pathogenesis of the disorder.  相似文献   
55.
Halperin  DS; Estrov  Z; Freedman  MH 《Blood》1989,73(5):1168-1174
To clarify the defective erythropoiesis in eight patients with Diamond- Blackfan anemia, we studied their bone marrow response in vitro to recombinant human interleukin-3 (IL-3) and recombinant granulocyte- macrophage colony-stimulating factor (GM-CSF). In an erythropoietin- containing assay system, specimens from six of the eight patients yielded low numbers of erythroid colonies compared to control values, and in five of these no erythropoietin dose-response could be elicited. Addition of IL-3, GM-CSF or both to cultures from the six patients had no effect on CFU-E-derived colonies. In contrast, IL-3 but not GM-CSF induced a marked increase in the number (183%) and size of the BFU-E- derived colonies in five of the six cases and partially corrected the impaired dose-response to erythropoietin in four. Bone marrow from the other two patients yielded numbers of CFU-E and BFU-E colonies comparable to controls and manifested similar increments in colonies with increasing concentrations of erythropoietin. When IL-3 was added to these cultures, further increments were observed in the number and size of BFU-E colonies. We conclude that IL-3 enhanced the marrow erythropoiesis in most of the patients and exerted a corrective effect on the aberrant colony formation in the presence of erythropoietin. The data raise the possibility of IL-3 as a therapeutic agent in Diamond- Blackfan anemia.  相似文献   
56.
57.
Pregnancy is widely authorized in systemic lupus erythematosus (SLE). Fertility is similar in SLE and in the general population although the age of menarche seems higher. Some cases of sterility might be attributed to SLE because of autoimmune ovaritis or antiphospholipid antibodies (aPL). These antibodies might lead to endothelial activation and thrombosis by influencing homeostasis, complement activation, inhibition of protein C and annexin V. They might have a deleterious effect on embryonic implantation by adhesion to the trophoblast, inhibition of invasion and placentation and decreased hCG production. The most important part of sterility seems secondary to the use of cyclophosphamide and might be prevented by acetate leuprolide administration. Maternal morbidity seems correlated to SLE activity (controlled by pregnancy planning), hypertension, preeclampsia, Hemolysis, Elevated Liver Enzymes, Low Platelets (HELLP) syndrome, therapy and aPL. Hydroxychloroquine (HCQ) should be maintained throughout pregnancy. Aspirin is prescribed alone in patients with asymptomatic aPL and in addition to heparin if there is a history of thrombosis or fetal loss with aspirin. Fetal and neonatal morbidity correlate with prematurity, adverse effects or maternal steroid therapy and maternal anti-SSA antibodies with 1 to 2% risk of congenital atrioventricular block. Abnormal obstetrical echography-doppler examination is the best predictor of pregnancy outcome. Abnormal ombilical artery flow on the second trimester echodoppler examination and history of thrombophlebitis predict fetal or neonatal death. Abnormal uterine notch on the second trimester echodoppler examination predicts adverse pregnancy outcome. Except for the preventive therapy of congenital atrioventricular block, modalities of SLE pregnancy monitoring and therapy are now well established.  相似文献   
58.
OBJECTIVE: To describe epidemiological, clinical, and immunological characteristics and the longterm course of persistent mixed cryoglobulinemia (MC) in patients infected with hepatitis C virus (HCV). METHODS: Retrospective study of HCV infected patients (HCV RNA positive) who had persistent positive MC, with 2 immunochemical typings of MC carried out after 24-month minimum interval. RESULTS: In total, 125 patients were studied, aged 52 +/- 13 years at diagnosis of MC, with duration of HCV infection of 18 +/- 10 years. At entry, 60 patients had type II MC, 53 patients had type III, and 12 patients had the oligoclonal type. At the second immunochemical typing, after a mean interval of 45 +/- 20 months, MC was type II in 72 patients, type III in 39 patients, and the oligoclonal type in 14 patients. The proportion of cases of MC with the same immunochemical type was higher among patients with type II (78%) than type III (59%) or oligoclonal MC (17%) (p < 0.01). The MC that changed turned more to type II (55.5%) than type III (29%) or the oligoclonal type (15.5%) (p = 0.0002). MC vasculitis (purpura, arthralgia, peripheral neuropathy, renal involvement) and other extrahepatic manifestations (polyarteritis nodosa, lymphoma) in 60/125 patients was associated with advanced age (p < 0.01), a longer duration of infection (p < 0.05), type II MC (odds ratio = 5, p < 0.01), and a higher MC serum level (p < 0.01). CONCLUSION: During chronic active HCV infection, type II MC is more stable over time than type III and oligoclonal MC. The oligoclonal type appears to be an intermediate stage in the course of type III changing to type II MC. Symptomatic persistent HCV MC was associated with advanced age, longer duration of HCV infection, type II MC, and a higher MC serum level.  相似文献   
59.
60.
Cardiac abnormalities in patients with Beh?et disease (BD) include pericarditis, myocarditis, endocarditis with valvular regurgitation, intracardiac thrombosis, endomyocardial fibrosis, coronary arteritis with or without myocardial infarction, and aneurysms of the coronary arteries or sinus of Valsalva. Data regarding the clinical spectrum, prevalence, and outcome of cardiac lesions in BD are lacking. In this study, we report the main characteristics, treatment, and long-term outcomes of 52 patients with cardiac lesions from a cohort of 807 (6%) BD patients. Forty-five (86.5%) patients were male, with a mean (±SD) age at BD diagnosis of 29.3 ± 10.3 years.Cardiac involvement was the first feature of BD in 17 (32.7%) patients. Cardiac lesions included pericarditis (n = 20; 38.5%), endocarditis (mostly aortic insufficiency) (n = 14; 26.9%), intracardiac thrombosis (n = 10; 19.2%), myocardial infarction (n = 9; 17.3%), endomyocardial fibrosis (n = 4; 7.7%) and myocardial aneurysm (n = 1; 1.9%). Patients with cardiac involvement were more frequently male (86.5% vs. 64.9%; p < 0.01) and had more arterial (42.3% vs. 11.1%; p < 0.01) and venous lesions (59.6% vs. 35.8%; p < 0.01) compared to those without cardiac manifestations. Factors associated with complete remission of cardiac involvement were treatment regimens with oral anticoagulants, immunosuppressants, and colchicine. The 5-year survival rate was 83.6% and 95.8% (p = 0.03) in BD patients with and without cardiac involvement, respectively. After a median (Q1-Q3) follow-up of 3.0 (1.75-4.2) years, 8 patients had died, in 3 cases directly related to cardiac involvement.In conclusion, cardiac lesions affected 6% of our large cohort of BD patients. The prognosis of cardiac involvement in BD is poor and improves with oral anticoagulation, immunosuppressive therapy, and colchicine.  相似文献   
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