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31.
The T(c)-cell response to ectromelia virus infection was studied in BALB/c-H-2(db) mice which carry a loss mutation in the H-2D region that results in the absence from cell surfaces of a molecule (D’) bearing certain public H-2 specificities. When infected, these mice showed a poor response of T(c) cells that recognize H-2D(d) plus virus-specific determinants on infected macrophage targets, but gave a normal response to H-2K d plus virus-specific antigens. However, their own infected macrophages do display wild-type antigenic patterns involving virus and H-2D(d) since they were killed as efficiently as wild-type (BALB/c,H- 2(d))-infected cells by T(c) cells specific only for H-2D(d) plus viral antigens. When tested in vitro, infected BALB/c-H-2(db) cells stimulated a poor T(c)-cell response to H-2D plus virus-specific antigens, but stimulated a normal response (in comparison with infected BALB/c macrophages) to H-2K(d) plus viral antigens. Uninfected BALB/c-H-2(db) cells stimulated a normal T(c)-cell response to minor H antigens or trinitrophenyl in association with H-2D(d), thus suggesting that the defective response to infection may reside in a failure of the relevant H-2D(d) antigens of mutant cells to physically associate with viral antigens. Close association of viral and H-2D-coded molecules was also suggested by ability of specific anti-H-2K or -H-2D to partially block T(c)-cell-mediated lysis of infected targets. These results were interpreted to mean that H-2Dd-dependent, virus- immune T(c) cells recognized an antigenic pattern consisting of virus- specific and H-2D(d) determinants with the latter borne on an H-2D molecule carrying serologically-defined H-2D(d) private specificities. A second H-2D(d)-coded molecule (D’) was not required for recognition and lysis by activated T(c) cells, but was apparently necessary for efficient stimulation of precursor T(c) cells, perhaps by promoting appropriate physical association of viral and H-2D(d) molecules.  相似文献   
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Background: The goal of this retrospective study was to compare the efficacy and toxicity of lenalidomide–dexamethasone (len/dex) vs. melphalan–prednisone–lenalidomide (MPR) as upfront therapy for newly diagnosed elderly patients with myeloma. Methods: Data from 51 patients enrolled in an Italian phase I/II trial and treated with MPR were analyzed and compared with data from 38 patients, seen at the Mayo Clinic, treated with len/dex and enrolled in phase II/III trials. Results: On intention‐to‐treat analysis, time to progression (median: 24.7 vs. 27.5 months in MPR and len/dex groups, respectively, P = 0.903), progression‐free survival (median: 24.7 vs. 27.5 months in MPR and len/dex groups, respectively, P = 0.926), and overall survival (2‐yr overall survival: 86.2% in MPR vs. 89.1% in len/dex, P = 0.730) were not significantly different between the two groups. Results were confirmed when the analysis was restricted to MPR and len/dex matched pair mates. Hematologic grade 3–4 toxicities were more common with MPR (neutropenia: 66.7% vs. 21.1%, P < 0.001; thrombocytopenia: 31.4% vs. 2.6%, P < 0.001). Grade 3–4 gastrointestinal events (13.2% vs. 3.9%, P = 0.132), thrombotic events (13.2% vs. 5.9%, P = 0.279), and fatigue (10.5% vs. 3.9%, P = 0.395) were more common with len/dex. Conclusions: Results show that both MPR and len/dex are efficacious regimens for elderly patients with myeloma. Randomized trials are needed to confirm these results.  相似文献   
34.
Vaccines are attractive as consolidation therapy after autologous stem cell transplantation (ASCT) for multiple myeloma (MM). We report the results of a phase II trial of the immunotherapeutic, APC8020 (Mylovenge?), given after ASCT for MM. We compared the results with that of other patients with MM who underwent ASCT at Mayo Clinic during the same time period. Twenty‐seven patients were enrolled on the trial between July, 1998 and June, 2001, and the outcomes were compared to that of 124 consecutive patients transplanted during the same period, but not enrolled on the trial. The median (range) follow‐up for patients still alive from the vaccine trial is 6.5 (2.9–8 years), and 7.1 (6–8 years) in the control group. The median age was 57.4 range (36.1–71.3) in the DB group and 56.4 (range, 30–69) in the trial group. Known prognostic factors including PCLI, B2M, and CRP were comparable between the groups. The median overall survival for the trial patients was 5.3 years (95% CI: 4.0 years—N/A) compared to 3.4 years (95% CI: 2.7–4.6 years) for the DB group (P = 0.02). The median time to progression and progression‐free survival for the trial group was similar to the DB group. Although not a controlled trial, the vaccines given after ASCT appear to be associated with improved overall survival compared to historical controls. This approach warrants further investigation to confirm this and define the role of vaccine therapy in myeloma. Am. J. Hematol. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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Multiple myeloma remains incurable despite the use of high-dose therapy and autologous stem cell transplantation and the introduction of novel agents with high response rates. The use of an uncontaminated stem cell graft and the presence of a graft-versus-myeloma effect led to the use of allogeneic stem cell transplantation in myeloma, and it has been part of the therapeutic armamentarium for more than a decade. Early results were discouraging due to high transplantation-related mortality and high rates of graft-versus-host disease. More recently, better supportive care, increasing experience with this modality and its complications, use of reduced-intensity conditioning regimens, and its use earlier in the course of disease have led to improved outcomes. Patients with high-risk genetic and biochemical features do poorly with conventional therapies, and allogeneic transplantation offers the potential for long-term disease control.  相似文献   
37.
Philip S  Armstead WM 《Brain research》2003,979(1-2):98-103
Previous studies in piglets have shown that the generation of oxygen free radicals (O(-)(2)) following traumatic brain injury and hypoxia/ischemia contribute to the reversal of N-methyl-D-aspartate (NMDA)-induced pial artery dilation to vasoconstriction. This study determined the contribution of protein tyrosine kinase (PTK) and mitogen-activated protein (MAPK) activation to impairment of NMDA cerebrovasodilation by O(-)(2) in piglets equipped with a closed window. Exposure of the cerebral cortex to a xanthine oxidase O(-)(2) generating system (OX) reversed NMDA (10(-8), 10(-6) M) dilation to vasoconstriction but such impairment was partially prevented by the PTK inhibitor, genistein, the MAPK (ERK isoform) inhibitor, U0126, and the MAPK (p38 isoform) inhibitor, SB203580 (9+/-1 and 15+/-1 vs. -1+/-1 and -1+/-1 vs. 5+/-1 and 9+/-1% for sham control, OX and OX in the presence of genistein, respectively). However, the p38 MAPK inhibitor, SB203580, prevented NMDA dilator impairment significantly less than the ERK MAPK inhibitor, U0126. Similar results were obtained for glutamate. These data show that PTK and MAPK activation by the presence of O(-)(2) contributes to the impairment of NMDA dilation. Furthermore, these data indicate a differential role for ERK and p38 MAPK activation in impairment of NMDA dilation by O(-)(2) in the brain.  相似文献   
38.
Arsenic trioxide (As(2)O(3)) has been found effective in the treatment in the treatment of acute promyelocytic leukemia (APML). Most studies with As(2)O(3) involve patients with APML who have relapsed following standard therapy. Between January 1998 and July 2000, 14 patients were recruited for an ongoing trial of As(2)O(3) in the treatment of newly diagnosed APML. Arsenic trioxide was administered at a dose of 10 mg/day until complete remission (CR) was achieved. Afterward, a consolidation course and a maintenance schedule consisting of As(2)O(3) as a single agent were administered over 6 months. There were 3 early deaths related to intra-cerebral hemorrhage: two on day 3 and one on day 4. Of the 11 evaluable patients, one died on day 21 secondary to uncontrolled sepsis, while the remaining 10 (91%) have attained CR. The average time to CR was 52.3 days (range: 34-70 days). One patient developed an isolated central nervous system (CNS) relapse and subsequently went into a second CR following therapy with triple intrathecal chemotherapy, cranial irradiation, and an additional 4-week course of systemic As(2)O(3). This patient, as well as the remaining nine, has continued to remain in CR at a median follow up of 15 months (range: 2-33 months). Eight out of 10 patients achieved molecular remission at variable periods during their consolidation and maintenance schedules. One patient developed an ATRA syndrome and was administered daunorubicin (40 mg/day) for 2 days. The side effects with this therapy were minimal and did not require cessation of therapy in any patient. There was no significant hepatic toxicity. In our experience, arsenic trioxide is effective in inducing and maintaining remission in patients with APML with minimal side effects. The optimal regimen and total dose required need to be defined.  相似文献   
39.
Multiple myeloma (MM)--a malignancy of the bone marrow--remains incurable by current therapies, and there is an urgent need for new drugs based on a better understanding of the underlying disease biology. MM is characterized by monoclonal plasma cells that accumulate in the bone marrow, which provides a microenvironment that promotes tumor cell growth and survival and protection against various therapeutic agents. The MM cell interacts with bone marrow stromal cells and endothelial cells, as well as osteoblasts and osteoclasts. Our understanding of the tumor microenvironment has already prompted the development of new agents that are aimed at disrupting the multiple facets of these interactions. It has also enabled the development of a comprehensive and rational approach to preclinical evaluation of new agents, facilitating the translation of in vitro studies to in vivo tumor models and, subsequently, to clinical trials. In this review, we describe the preclinical studies that led to the development of clinical trials of thalidomide and its immunomodulatory derivatives as therapeutic agents for MM. These drugs, alone or in combination, have shown impressive activity at all stages of the disease, and these demonstrations of clinical benefit have in turn validated our model systems for drug discovery in MM. Integration of data from clinical trials and laboratory studies will allow the design of future clinical trials that combine thalidomide and its derivatives with other drugs, ultimately leading to more effective therapies and better outcomes in patients with MM.  相似文献   
40.
Homozygous HbE [beta26(B8)Glu-->Lys] is a clinically mild disorder with no significant symptoms. However, we have frequently noted hyperbilirubinemia among patients with homozygous HbE in the Indian population, with jaundice being the major complaint at presentation. A study of the UGT1A1 gene polymorphism shows that the variant TA7 in the promoter region of the UGT1A1 gene is associated with hyperbilirubinemia in homozygous HbE patients.  相似文献   
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