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961.
BACKGROUND: Optimal use of disease-modifying antirheumatic drugs (DMARDs) in rheumatoid arthritis is vital if progression of disease is to be reduced. Methotrexate (MTX) and sulfasalazine (SASP) are widely used inexpensive DMARDs, recently often combined despite no firm evidence of benefit from previous studies. Aim: To establish whether a combination of SASP and MTX is superior to either drug alone in patients with rheumatoid arthritis with a suboptimal response to 6 months of SASP. METHODS: A randomised controlled study of step-up DMARD treatment in early rheumatoid arthritis. In phase I, 687 patients received SASP for 6 months. Those with a disease activity score (DAS) > or =2.4 were offered additional treatment in phase II (SASP alone, MTX alone or a combination of the two). The primary outcome measure was change in DAS. RESULTS: At 6 months, 191 (28%) patients had a DAS <2.4, 123 (18%) were eligible but did not wish to enter phase II, 130 (19%) stopped SASP because of reversible adverse events and 165 (24%) entered phase II. DAS at 18 months was significantly lower in those who received combination treatment compared with those who received either SASP or MTX: monotherapy arms did not differ. Improvement in European League Against Rheumatism and American College of Rheumatology 20, 50 and 70 scores favoured combination therapy. CONCLUSIONS: In this "true-to-life" study, an inexpensive combination of DMARDs proved more effective than monotherapy in patients with rheumatoid arthritis with a suboptimal response to SASP. There was no increase in toxicity. These results provide an evidence base for the use of this combination as a component of tight control strategies.  相似文献   
962.
963.
Mutations of the TP53 tumor suppressor gene have been associated with poor survival in some series of diffuse large B-cell lymphoma (DLBCL) but not in other studies. The purpose of this study was to identify the frequency of TP53 alterations (mutations or deletions), characterize the gene expression of mutant/deleted cases, and determine the effects of mutations on survival. In a series of DLBCL that had previous gene expression profiling, we identified 24 mutations in 113 cases (21%). There was no difference in the frequency of mutations in the molecular subgroups of DLBCL. Twelve (50%) of the 24 cases had mutations localized to the DNA-binding codons in the core domain of TP53. The presence of any TP53 mutation correlated with poor overall survival (OS; P = .044), but DNA-binding mutations were the most significant predictor of poor OS (P < .001). Multivariate analysis confirmed that the International Prognostic Index, tumor size, and TP53 DNA-binding mutations were independent predictors of OS. Gene expression analysis showed that TRAILreceptor-2 (DR5) was the most differentially underexpressed gene in the TP53 mutated cases. Investigation is warranted into targeted therapy toward TRAIL receptor-2, to potentially bypass the adverse effect of mutated TP53 in DLBCL.  相似文献   
964.
The natural history of EBV and CMV reactivation and the potential for serious complications following antibody-based immunosuppressive treatment for bone marrow failure syndromes in the absence of transplantation is not known. We monitored blood for EBV and CMV reactivation by polymerase chain reaction (PCR) weekly in 78 consecutive patients (total of 99 immunosuppressive courses) with aplastic anemia. Four regimens were studied: (1) HC, horse ATG/cyclosporine; (2) HCS, horse ATG/CsA/sirolimus; (3) RC, rabbit ATG/CsA; and (4) CP, alemtuzumab. There were no cases of EBV or CMV disease, but EBV reactivation occurred in 82 (87%) of 94 and CMV reactivation in 19 (33%) of 57 seropositive patients after starting immunosuppression. The median peak EBV copies were higher in the RC group when compared with HC, HCS, and alemtuzumab (P < .001). The median duration of PCR positivity for EBV was higher in the RC group compared with HC, HCS, and alemtuzumab (P = .001). Subclinical reactivation of both EBV and CMV is common and nearly always self-limited in patients with bone marrow failure receiving immunosuppression; different regimens are associated with different intensity of immunosuppression as measured by viral load and lymphocyte count; and viral reactivation patterns differ according to immunosuppressive regimens.  相似文献   
965.
966.
Despite compliance with lifestyle recommendations, some children and adolescents with high-risk hyperlipidemia will require lipid-lowering drug therapy, particularly those with familial hypercholesterolemia. The purpose of this statement is to examine new evidence on the association of lipid abnormalities with early atherosclerosis, discuss challenges with previous guidelines, and highlight results of clinical trials with statin therapy in children and adolescents with familial hypercholesterolemia or severe hypercholesterolemia. Recommendations are provided to guide decision-making with regard to patient selection, initiation, monitoring, and maintenance of drug therapy.  相似文献   
967.
Adenoid cystic carcinoma is a malignant salivary gland neoplasm with recurrence and metastasis. We studied the expression of a malignancy-related non-integrin laminin receptor, the 67LR, in this neoplasm. Immunohistochemistry showed 67LR in adenoid cystic carcinoma. This receptor binds a sequence of laminin β1 chain, the YIGSR peptide. We studied the effect of 67LR and YIGSR in cells (CAC2) from adenoid cystic carcinoma. Three-dimensional cultures of cells embedded into either laminin-111 gel (controls) or YIGSR-enriched laminin-111 (treated) were prepared and studied by light microscopy. CAC2 cells treated with YIGSR appeared fibroblast-like, while control cells were epithelioid. Blockage of 67LR by antibody abolished YIGSR effect in three-dimensional cultures. We analysed the relevance of 67LR and YIGSR on β-catenin expression in CAC2 cells. Immunofluorescence and immunoblot showed that YIGSR decreased β-catenin, while blockage of 67LR restored the presence of this molecule. The 67LR and YIGSR induced fibroblast-like morphology in CAC2 cells, with disruption of cell–cell contacts and decrease of β-catenin. These features resemble epithelial–mesenchymal transition (EMT). EMT also increases cell migration. In monolayer assays YIGSR increased migration of CAC2 cells. We conclude that 67LR and YIGSR are involved in epithelial–mesenchymal transition, modulation of β-catenin expression, and migratory activity of CAC2 cells.  相似文献   
968.
OBJECTIVE: The objective was to assess the efficacy and safety of erythropoiesis-stimulating proteins (ESPs) in anemia of myelodysplastic syndrome (MDS). METHOD: A systematic review and meta-analysis was conducted covering English-language studies published from 1980 to December 2005. RESULTS: Fifty-nine studies qualified: five controlled trials (n = 354), all epoetin versus control (EvC); 51 epoetin single-arm studies (n = 1,650); and three darbepoetin single-arm studies (n = 102). In the EvC studies, epoetin patients demonstrated a significant advantage over controls in terms of hemoglobin (Hb) response (odds ratio, 5.2; 95% confidence interval, 2.5-10.8). Hb response was 48.1% in single-arm darbepoetin studies, 32.1% in epoetin single-arm studies, and 27.3% in EvC studies. Major Hb response averaged 38.8% in darbepoetin studies, 24.5% in epoetin single-arm studies, and 11.4% in EvC studies. Stratified analyses suggest that lower baseline erythropoietin levels, longer treatment durations, and concurrent iron may be associated with greater Hb response to ESPs. None of the analyzable predictors of Hb response (gender, baseline Hb, ESP type, and ESP duration) were significant in meta-regression analyses. In the few studies with quality-of-life measures, ESP groups attained a pre-post change (Functional Assessment of Cancer Therapy - Fatigue) that exceeded minimum clinically important differences. Selected adverse event rates did not differ between the epoetin and darbepoetin groups. CONCLUSION: Published studies suggest that ESPs are efficacious in anemia of MDS. Hb response appears higher in darbepoetin patients than in epoetin patients, and safety appears comparable, but darbepoetin data are sparse, and there are as yet no direct comparison studies.  相似文献   
969.
Complex musculoskeletal defects resulting from cancer, congenital absence, and trauma represent a unique reconstructive challenge. Autologous tissue is often unavailable to reconstruct these deformities. Composite tissue allograft transplantation represents a unique solution for these clinical problems. Face, hand, or limb transplants can be performed in a single procedure. However, the use of chronic nonspecific systemic immunosuppression can lead to side effects such as drug toxicity, opportunistic infections, and malignancies. This article explores various cell-based therapies that represent promising modalities to reduce chronic immunosuppression and alter the risk/benefit ratios for the prospect of composite tissue allograft transplantation.  相似文献   
970.
In clinical research there is a real possibility to have some conflict of interests. Even for the researcher, the identification of these conflicts cannot be clear. There are many aspects to be considered, involving all participants of the process: the research subject, the researcher, the institution where the research is carried through, the sponsor, the ethics committees, the regulating agencies, the scientific community and the society. The conclusion is that conflicts of interests are common and inevitable in the academic field. The challenge is not to eradicate them, but to recognize them and to manage them properly. The only acceptable way to do this is to expose clearly the conflicts of interests and always to submit the clinical research projects to the ethics committees.  相似文献   
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