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Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is characterized by an acquired immune defect that can cause autoimmune complications, including anemia and thrombocytopenia. We conducted an observational study of the epidemiology, clinical presentation and significance of autoimmune complications of CLL/SLL in 132 patients from a large population (>45,000 veterans), in which at least 90% of patients with CLL/SLL have been previously identified. Over a period of 12.5 years, 12 patients (9.1%) had autoimmune complications; of these, 6 (4.5%) had autoimmune hemolytic anemia (AIHA), 5 (3.8%) had immune thrombocytopenia (ITP), and 1 (0.8%) had pure red blood cell aplasia (PRBA). All 6 cases of AIHA had a positive direct immunoglobulin test for IgG and C3d. In 6 patients, CLL/SLL was an incidental finding at the time of presentation with autoimmune cytopenia. Nine out of 10 patients responded to immunosuppressive therapy, which was complicated by serious infection in 7 cases, one of which was fatal. The major cause of mortality in patients with autoimmune complications of CLL/SLL was secondary malignancy. Survival of patients with immune cytopenia was not significantly different from CLL/SLL patients without immune cytopenia. Among patients with anemia or thrombocytopenia, mortality was significantly higher in those with bone marrow failure compared to an autoimmune etiology. We show that in a non-referred population with a high incidence of CLL/SLL, autoimmune cytopenia can occur early in the natural history of the disease. These data suggest that the Rai and Binet classifications for CLL need to be modified for patients with autoimmune cytopenia. .  相似文献   
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Vega E  Rudolph MI 《Endocrine》2002,18(2):167-172
Oxytocin (OT) inhibits the uptake of serotonin (5HT) into uterine mast cells. This may modulate 5HT bioavailability in the myometrium. Because 5HT is an important endogenous uterotonic compound, it has been postulated that this effect of OT may contribute to its potency as a labor inducer. This also predicts the presence of oxytocin receptors (OTRs) and transducing signals that will interact with 5HT transporters (SERT) in mast cells. In this study, OTR and SERT were characterized in murine peritoneal mast cells by radioligandbinding studies. Saturation assays for OTR showed no changes in K d along the estrous cycle (6.95±2.76 nM in estrus and 4.07±1.73 nM in diestrus) but an increase in B max in estrus (0.71±0.08 pmol/106 cells and 0.37±0.05 pmol/106 cells in estrus and diestrus, respectively). B max and K d for SERT were not affected along the estrous cycle. The signaling between the OTR and the SERT was analyzed by measuring the extent of inhibition of OT and PMA (activator of protein kinase C on 5HT uptake and the capability of Ro318220 (specific inhibitor of PKC) to increase 5HT uptake and block the effect of the above compounds in mast cells. The results showed that in murine peritoneal mast cells in vitro (1) ovarian hormones modulate OTR but not SERT expression, (2) the magnitude of OT action on 5HT uptake depends on the number of OTRs expressed in mast cells, and (3) the signaling between OTR and the SERT is mediated through the activation of protein kinase C. It is concluded that the ovarian hormones have a modulatory action on 5HT uptake which involves OT-mediated mechanism.  相似文献   
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Cyclophosphamide, doxorubicin, vincristine, and prednisone, given every 3 weeks (CHOP-21), is standard chemotherapy for aggressive lymphomas. To determine whether biweekly CHOP (CHOP-14) with or without etoposide is more effective than CHOP-21, 689 patients ages 61 to 75 years were randomized to 6 cycles of CHOP-21, CHOP-14, CHOEP-21 (CHOP plus etoposide 100 mg/m2 days 1-3), or CHOEP-14. Patients in the 2-weekly regimens received granulocyte colony-stimulating factor (G-CSF) starting from day 4. Patients received radiotherapy (36 Gy) to sites of initial bulky disease and extranodal disease. Complete remission rates were 60.1% (CHOP-21), 70.0% (CHOEP-21), 76.1% (CHOP-14), and 71.6% (CHOEP-14). Five-year event-free and overall survival rates were 32.5% and 40.6%, respectively, for CHOP-21 and 43.8% and 53.3%, respectively, for CHOP-14. In a multivariate analysis, the relative risk reduction was 0.66 (P =.003) for event-free and 0.58 (P <.001) for overall survival after CHOP-14 compared with CHOP-21. Toxicity of CHOP-14 and CHOP-21 was similar, but CHOEP-21 and in particular CHOEP-14 were more toxic. Due to its favorable efficacy and toxicity profile, CHOP-14 should be considered the new standard chemotherapy regimen for patients ages 60 or older with aggressive lymphoma.  相似文献   
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