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71.
Autologous bone marrow transplantation (BMT) was utilized as therapy for 23 patients with acute lymphoblastic leukemia (ALL) in second or greater remission. Bone marrow was treated in vitro with a combination of monoclonal antibodies, consisting of BA-1, BA-2, BA-3, and baby rabbit complement (BRC'). All patients were prepared for transplantation with cyclophosphamide and fractionated total body irradiation. Engraftment occurred in all 23 patients. Seven of 23 patients remain relapse-free from six to 32 months (median, 21.4 months) posttransplant. Failures were due to relapse with the exception of one patient who died of infection. This study demonstrates that autologous BMT using in vitro marrow treatment with BA-1, BA-2, BA-3, and BRC' is safe, allows engraftment, and results in prolonged survival for some patients with ALL in second or greater remission.  相似文献   
72.
73.
Fourteen patients with high-risk T-lineage acute lymphoblastic leukemia (ALL) in complete remission underwent autologous bone marrow transplantation (BMT) in an attempt to eradicate their residual disease burden. A combined immunochemotherapy protocol using a cocktail of two immunotoxins directed against CD5/Tp67 and CD7/Tp41 T-lineage differentiation antigens in combination with the in vitro active cyclophosphamide congener 4-hydroperoxy-cyclophosphamide (4-HC) was used to purge autografts. Despite high dose pretransplant radiochemotherapy and effective purging of autografts, 9 of 14 patients relapsed at a median of 2.5 months (range, 1.2 to 16.8 months) post BMT. Two patients remain alive and disease free at 26 and 28 months post BMT. We used a novel quantitative minimal residual disease (MRD) detection assay, which combines fluorescence activated multiparameter flow cytometry and cell sorting with leukemic progenitor cell (LPC) assays, to analyze remission bone marrow (BM) samples from T-lineage ALL patients for the presence of residual LPCs. Notably, high numbers of residual LPC detected in remission BM before BMT constituted a poor prognostic indicator, providing the first evidence for the biologic significance and clinical value of in vitro T-lineage ALL LPC assays. The median value for the residual leukemia burden before BMT, was approximately 8.6 x 10(3) LPC/10(8) mononuclear cells (MNC) (approximately 0.0086% LPC). Patients with a residual leukemia burden less than this median value appeared to have a better outlook for remaining free of relapse after autologous BMT than patients with a greater leukemia burden (53 +/- 25% v 14 +/- 13%, P = .006, Mantel-Cox). By comparison, the log kill efficacy of purging, the remaining numbers of LPC in purged autografts, or the estimated numbers of reinfused LPC, did not correlate with the probability of disease-free survival (DFS). These results indicate that the primary reason for the recurrence of leukemia was inefficient pretransplant radiochemotherapy rather than inefficient purging of autografts.  相似文献   
74.
BACKGROUNDThe accountable care organization (ACO) is a new organizational form to manage patients across the continuum of care. There are numerous questions about how ACOs should be optimally structured, including compensation arrangements with primary care physicians.METHODSUsing data from a national survey of physician practices, we compared primary care physicians’ compensation between practices in ACOs and practices that varied in their financial risk for primary care costs using 3 groups: practices not participating in a Medicare ACO and with no substantial risk for primary care costs; practices not participating in an ACO but with substantial risk for primary care costs; and practices participating in an ACO regardless of their risk for primary care costs. We measured physicians’ compensation as the percentage of compensation based on salary, productivity, clinical quality or patient experience, and other factors. Regression models estimated physician compensation as a function of ACO participation and risk for primary care costs while controlling for other practice characteristics.RESULTSPhysicians in ACO and non-ACO practices with no substantial risk for costs on average received nearly one-half of their compensation from salary, slightly less from productivity, and about 5% from quality and other factors. Physicians not in ACOs but with substantial risk for primary care costs received two-thirds of their compensation from salary, nearly one-third from productivity, and slightly more than 1% from quality and other factors. Participation in ACOs was associated with significantly higher physician compensation for quality; however, participation was not significantly associated with compensation from salary, whereas financial risk was associated with much greater compensation from salary.CONCLUSIONAlthough practices in ACOs provide higher compensation for quality, compared with practices at large, they provide a similar mix of compensation based on productivity and salary. Incentives for ACOs may not be sufficiently strong to encourage practices to change physician compensation policies for better patient experience, improved population health, and lower per capita costs.  相似文献   
75.
Chronic graft-versus-host disease (GVHD) refractory to standard immunosuppressive therapy remains a major cause of morbidity and mortality after allogeneic bone marrow transplantation (BMT). Thalidomide may be effective in some patients with high-risk or refractory chronic GVHD. We report a single-institution study of thalidomide in 37 BMT patients with extensive chronic GVHD refractory to standard immunosuppressive therapy. Acute GVHD occurred in 34 (91%) of patients and evolved progressively into chronic GVHD in 23 (62%) patients. Thalidomide was added to standard immunosuppressive therapy a median of 11 months (range 0-105 months) after the diagnosis of chronic GVHD. Fourteen of 37 (38%) patients responded after introduction of thalidomide (one complete, 13 partial). Ten of 21 (46%) children and four of 16 (25%) adults responded. Responses were seen in eight of 17 (47%) recipients of related donor marrow and six of 20 (30%) recipients of unrelated donor marrow. Eight of 23 (34%) patients with progressive onset of chronic GVHD showed a response. There were no deaths among the responders. The remaining 23 patients (62%) did not respond and of these only two survive, one with progressive scleroderma, and the other with bronchiolitis obliterans. Chronic GVHD with associated infection (most commonly disseminated fungal infection) was a major contributor to mortality in all cases. Overall, after initiation of thalidomide, the 2-year Kaplan-Meier survival was 41% (95% C.I. 24%-59%). We conclude that thalidomide is a useful and well-tolerated therapy for patients with previously treated refractory chronic GVHD, including those with progressive onset of chronic GVHD, recipients of unrelated donor marrow, and children. Earlier introduction of thalidomide as an adjunct to standard immunosuppressive therapy may lead to more frequent responses and possible better survival.  相似文献   
76.
Summary. This paper describes studies on the source, preparation, characterization and storage of human ferritin for use as a standard for the immunoassay of serum ferritin. Ferritin was prepared from the liver or spleen by methods including either ultracentrifugation or cadmium sulphate crystallization. Preparations were characterized by polyacrylamide gel electrophoresis in dissociating and non-dissociating buffers, iso-electric focusing, analysis of amino acid composition and measurement of protein content. The protein content of solutions of liver or spleen ferritin may be determined by the method of Lowry with bovine serum albumin as standard. Lyophilization under carefully controlled conditions in buffer containing high concentrations of albumin provides a stable preparation of ferritin. Accelerated degradation and collaborative immunological studies of two lyophilized preparations of ferritin, one from liver and one from spleen, indicate that either is an acceptable reference material.  相似文献   
77.
An adverse environment around conception and implantation influences later fetal growth and development to term in humans and sheep. Indeed, preimplantation undernutrition of rats elevated the systolic blood pressure of the resultant adult offspring. In this study, adult cardiovascular function is examined in a slower growing, non-litter-bearing species after peri-implantation undernutrition. Eight ewes were fed to 50% equivalent food intake of 12 control ewes from 1 to 30 days (term approximately 147 days) only. Following consumption of an adequate diet to term, natural lambing, and then weaning, resting cardiovascular status and baroreflex function were examined in the resultant young adult offspring. Birth weight and postnatal growth to 1 year of age were unaffected by early undernutrition; however, nutrient-restricted sheep had increased pulse pressure, a reduced rate pressure product, and a leftward shift in their baroreflex function curve. Baroreflex sensitivity during angiotensin II infusion was also blunted in early nutrient-restricted sheep but the tachycardia following a reduction in central blood pressure appeared potentiated, relative to controls. The data suggest that peri-implantation undernutrition may program long-term cardiovascular dysfunction that ultimately increases the risk of hypertension later in life. An increase in regional angiotensin II activity during this critical early phase of development is a likely candidate mechanism for the effects observed. The data have broad implications for the health outcome of those offspring from mothers who were poorly nourished during early, often unknown pregnancy and for embryos artificially manipulated because of infertility treatment.  相似文献   
78.
Amino-quinazoline BRaf kinase inhibitor 2 was identified from a library screen as a modest inhibitor of the unfolded protein response (UPR) regulating potential anticancer target IRE1α. A combination of crystallographic and conformational considerations were used to guide structure-based attenuation of BRaf activity and optimization of IRE1α potency. Quinazoline 6-position modifications were found to provide up to 100-fold improvement in IRE1α cellular potency but were ineffective at reducing BRaf activity. A salt bridge contact with Glu651 in IRE1α was then targeted to build in selectivity over BRaf which instead possesses a histidine in this position (His539). Torsional angle analysis revealed that the quinazoline hinge binder core was ill-suited to accommodate the required conformation to effectively reach Glu651, prompting a change to the thienopyrimidine hinge binder. Resulting analogues such as 25 demonstrated good IRE1α cellular potency and imparted more than 1000-fold decrease in BRaf activity.  相似文献   
79.
We assessed late mortality in 854 individuals who had survived 2 or more years after autologous hematopoietic cell transplantation (HCT) for hematologic malignancies. Median age at HCT was 36.5 years, and median length of follow-up was 7.6 years. Overall survival was 68.8% +/- 1.8% at 10 years, and the cohort was at a 13-fold increased risk for late death (standardized mortality ratio [SMR] = 13.0) when compared with the general population. Mortality rates approached those of the general population after 10 years among patients at standard risk for relapse at HCT (SMR = 1.1) and in patients undergoing transplantation for acute myeloid leukemia (AML; SMR = 0.9). Relapse of primary disease (56%) and subsequent malignancies (25%) were leading causes of late death. Relapse-related mortality was increased among patients with Hodgkin disease (HD; relative risk [RR] = 3.6), non-Hodgkin lymphoma (NHL; RR = 2.1), and acute lymphoblastic leukemia (ALL; RR = 6.5). Total body irradiation (RR = 0.6) provided a protective effect. Nonrelapse-related mortality was increased after carmustine (RR = 2.3) and with use of peripheral blood stem cells (RR = 2.4). Survivors were more likely to report difficulty in holding jobs (RR = 9.4) and in obtaining health (RR = 7.7) or life insurance (RR = 8.4) when compared with siblings. Although mortality rates approach that of the general population after 10 years in certain subgroups, long-term survivors of autologous HCT continue to face challenges affecting their health and well-being.  相似文献   
80.
Incidence of epilepsy increases rapidly after age 65; recent studies indicate that approximately 10% of nursing home residents are being treated with antiepileptic drugs (AEDs). Almost all are being treated with first generation AEDs. The average nursing home patient receives six medications, has age-related changes in protein binding, decreases in hepatic and renal clearance, and may have alterations in gastrointestinal absorption. AEDs that do not have drug-drug interactions, are not metabolized by the liver, and are readily absorbed may offer benefits in this population. New studies are demonstrating that the first generation AEDs have a number of shortcomings for treating older patients, whereas some of the newer AEDs may overcome these limitations. This paper reviews the present knowledge base and compares properties of the first generation AEDs with newer agents to develop a more rational approach for drug selection in older adults.  相似文献   
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