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181.

Background

There is increasing recognition of sex/gender differences in health and the importance of identifying differential effects of interventions for men and women. Yet, to whom the research evidence does or does not apply, with regard to sex/gender, is often insufficiently answered. This is also true for systematic reviews which synthesize results of primary studies. A lack of analysis and reporting of evidence on sex/gender raises concerns about the applicability of systematic reviews. To bridge this gap, this pilot study aimed to translate knowledge about sex/gender analysis (SGA) into a user-friendly ‘briefing note’ format and evaluate its potential in aiding the implementation of SGA in systematic reviews.

Methods

Our Sex/Gender Methods Group used an interactive process to translate knowledge about sex/gender into briefing notes, a concise communication tool used by policy and decision makers. The briefing notes were developed in collaboration with three Cochrane Collaboration review groups (HIV/AIDS, Hypertension, and Musculoskeletal) who were also the target knowledge users of the briefing notes. Briefing note development was informed by existing systematic review checklists, literature on sex/gender, in-person and virtual meetings, and consultation with topic experts. Finally, we held a workshop for potential users to evaluate the notes.

Results

Each briefing note provides tailored guidance on considering sex/gender to reviewers who are planning or conducting systematic reviews and includes the rationale for considering sex/gender, with examples specific to each review group’s focus. Review authors found that the briefing notes provided welcome guidance on implementing SGA that was clear and concise, but also identified conceptual and implementation challenges.

Conclusions

Sex/gender briefing notes are a promising knowledge translation tool. By encouraging sex/gender analysis and equity considerations in systematic reviews, the briefing notes can assist systematic reviewers in ensuring the applicability of research evidence, with the goal of improved health outcomes for diverse populations.  相似文献   
182.

Introduction

B cell depletion therapy is efficacious in rheumatoid arthritis (RA) patients failing on tumor necrosis factor (TNF) blocking agents. However, approximately 40% to 50% of rituximab (RTX) treated RA patients have a poor response. We investigated whether baseline gene expression levels can discriminate between clinical non-responders and responders to RTX.

Methods

In 14 consecutive RA patients starting on RTX (test cohort), gene expression profiling on whole peripheral blood RNA was performed by Illumina® HumanHT beadchip microarrays. Supervised cluster analysis was used to identify genes expressed differentially at baseline between responders and non-responders based on both a difference in 28 joints disease activity score (ΔDAS28 < 1.2) and European League against Rheumatism (EULAR) response criteria after six months RTX. Genes of interest were measured by quantitative real-time PCR and tested for their predictive value using receiver operating characteristics (ROC) curves in an independent validation cohort (n = 26).

Results

Genome-wide microarray analysis revealed a marked variation in the peripheral blood cells between RA patients before the start of RTX treatment. Here, we demonstrated that only a cluster consisting of interferon (IFN) type I network genes, represented by a set of IFN type I response genes (IRGs), that is, LY6E, HERC5, IFI44L, ISG15, MxA, MxB, EPSTI1 and RSAD2, was associated with ΔDAS28 and EULAR response outcome (P = 0.0074 and P = 0.0599, respectively). Based on the eight IRGs an IFN-score was calculated that reached an area under the curve (AUC) of 0.82 to separate non-responders from responders in an independent validation cohort of 26 patients using Receiver Operator Characteristics (ROC) curves analysis according to ΔDAS28 < 1.2 criteria. Advanced classifier analysis yielded a three IRG-set that reached an AUC of 87%. Comparable findings applied to EULAR non-response criteria.

Conclusions

This study demonstrates clinical utility for the use of baseline IRG expression levels as a predictive biomarker for non-response to RTX in RA.  相似文献   
183.
Citrullination is a post-translational modification catalysed by peptidylarginine deiminase and is a common feature of inflammation. The presence of anti-citrullinated protein/peptide antibodies (ACPA), however, is unique to rheumatoid arthritis. Several lines of evidence suggest that ACPA are important in the pathogenesis of rheumatoid arthritis. A popular hypothesis for this pathogenesis is a two-hit model. The first hit gives rise to ACPA, and the second hit, an unrelated episode of synovial inflammation accompanied by citrullination, is perpetuated by the pre-existing antibodies. This model suggests that reducing citrullination might ameliorate disease. Recent findings indicate that citrullination closely correlates with inflammation, and that glucocorticoids decrease peptidylarginine deiminase expression independent of their other anti-inflammatory effects.  相似文献   
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Plasma concentrations of the nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) increase already in the early stages of renal insufficiency. There is no agreement as to whether reduced renal plasma clearance (RPCL) contributes to this increase. Therefore, we investigated the relationship between estimated glomerular filtration rate (eGFR), RPCL, and plasma ADMA and SDMA in essential hypertensive patients with mild to moderate renal insufficiency. In 171 patients who underwent renal angiography, we drew blood samples from the aorta and both renal veins and measured mean renal blood flow (MRBF) using the (133)Xe washout technique. RPCL was calculated using arteriovenous concentration differences and MRBF. After correction for potential confounders, reduced eGFR was associated with higher plasma ADMA and SDMA [standardized regression coefficient (β) = -0.22 (95% confidence intervals: -0.41, -0.04) and β = -0.66 (95% confidence intervals: -0.83, -0.49), respectively]. However, eGFR was not independently associated with RPCL of ADMA. Moreover, reduced RPCL of ADMA was not associated with higher plasma ADMA. Contrary to ADMA, reduced eGFR was indeed associated with lower RPCL of SDMA [β = 0.21 (95% confidence intervals: 0.02, 0.40)]. In conclusion, our findings indicate that RPCL of ADMA is independent of renal function in hypertensive patients with mild to moderate renal insufficiency. Unlike the case for SDMA, reduced RPCL of ADMA is of minor importance for the increase in plasma ADMA in these patients, which indicates that increased plasma ADMA in this population is not a direct consequence of the kidneys failing as a plasma ADMA-regulating organ.  相似文献   
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Purpose: The use of endovascular coronary brachytherapy to prevent restenosis following percutaneous transluminal coronary angioplasty (PTCA) began in April 1997 at the Department of Interventional Cardiology of the Thoraxcenter at the University Hospital of Rotterdam. This article reviews the more than 250 patients that have been treated so far.Methods and Materials: The Beta-Cath System (Novoste), a manual, hydraulic afterloader with 12 90Sr seeds, was used in the Beta Energy Restenosis Trial (BERT-1.5, n=31), for compassionate use (n=25), in the Beta-Cath System trial (n=27) and in the Beta Radiation in Europe (BRIE, n=14). Since the Beta-Cath System has been commercialized in Europe, 57 patients have been treated and registered in RENO (Registry Novoste). In the Proliferation Reduction with Vascular Energy Trial (PREVENT), 37 patients were randomized using the Guidant-Nucletron remote control afterloader with a 32P source wire and a centering catheter. Radioactive 32P coated stents have been implanted in 102 patients. In the Isostent Restenosis Intervention Study 1 (IRIS 1), 26 patients received a stent with an activity of 0.75-1.5 μCi, and in the IRIS 2 (European 32P dose response trial), 40 patients were treated with an activity of 6-12 μCi. In two consecutive pilot trials, radioactive stents with non-radioactive ends (cold-end stents) and with ends containing higher levels of activity (hot-end stents) were implanted in 21 and 17 patients, respectively.Results: In the BERT-1.5 trial, the radiation dose, prescribed at 2 mm from the source train (non-centered), was 12 Gy (10 patients), 14 Gy (10 patients) and 16 Gy (11 patients). At 6-month follow-up, 8 out of 28 (29%) patients developed restenosis. The target lesion revascularization rate (TLR) was 7 out of 30 (23%) at 6 months and 8 out of 30 (27%) at 1 year. Two patients presented with late thrombosis in the first year. For compassionate use patients, a restenosis rate (RR) of 53% was observed. In the PREVENT trial, 34 of 37 patients underwent an angiographic 6-month follow-up. The doses prescribed at 0.5 mm depth into the vessel wall were 0 Gy (8), 28 Gy (9), 35 Gy (11) and 42 Gy (8). TLR was 14% in the irradiated patients and 25% in the placebo group. One patient developed late thrombosis. In the IRIS 1 trial, 23 patients showed an RR of 17% (in-stent). In the IRIS 2 trial, in-stent restenosis was not seen in 36 patients at 6-month follow-up. However, a high RR (44%) was observed at the stent edges.Conclusions: The integration of vascular brachytherapy in the catheterization laboratory is feasible and the different treatment techniques that are used are safe. Problems, such as edge restenosis and late thrombotic occlusion, have been identified as limiting factors of this technique. Solutions have been suggested and will be tested in future trials.  相似文献   
189.
Herpes simplex virus DNA polymerase is a heterodimer composed of a catalytic subunit, Pol, and an unusual processivity subunit, UL42, which, unlike processivity factors such as PCNA, directly binds DNA. The crystal structure of a complex of the C-terminal 36 residues of Pol bound to residues 1-319 of UL42 reveals remarkable similarities between UL42 and PCNA despite contrasting biochemical properties and lack of sequence homology. Moreover, the Pol-UL42 interaction resembles the interaction between the cell cycle regulator p21 and PCNA. The structure and previous data suggest that the UL42 monomer interacts with DNA quite differently than does multimeric toroidal PCNA. The details of the structure lead to a model for the mechanism of UL42, provide the basis for drug design, and allow modeling of other proteins that lack sequence homology with UL42 or PCNA.  相似文献   
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