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951.
Preclinical data indicate that radiotherapy works synergistically with pembrolizumab, but the effect and toxicity of this combination may depend on radiotherapy timing. We conducted a randomized phase 1 trial combining pembrolizumab with either sequential (A) or concomitant (B) stereotactic body radiotherapy (SBRT) in metastatic urothelial carcinoma (mUC). No dose-limiting toxicity occurred. Treatment-related adverse events (trAEs; Common Terminology Criteria for Adverse Events v4.0) of grade 1–2 occurred in six of nine and all nine patients in arms A and B, respectively. One grade 3 trAE occurred in arm B. No grade 4–5 trAEs occurred. Overall response rates of 0% and 44.4% were noted in arms A and B, respectively, as per Response Evaluation Criteria in Solid Tumors v1.1. The trial was not powered to compare efficacy between arms. Targeted sequencing of tissue DNA and circulating tumor DNA (ctDNA) revealed high genomic concordance. Treatment response was associated with ctDNA fraction decline. We conclude that sequential and concomitant SBRT can be safely combined with pembrolizumab in mUC and that the effect of SBRT timing on efficacy is worth exploring further.

Patient summary

This study assessed the safety of pembrolizumab combined with radiotherapy at two different time points in metastatic bladder cancer. We conclude that the combination treatment was well tolerated.  相似文献   
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Background

There is longstanding expert disagreement about the age at and frequency with which women should be screened for breast cancer. These debates are reflected in the conflicting recommendations about mammography issued by major professional organizations, such as the U.S. Preventive Services Task Force and the American Cancer Society. Previous research has shown that these recommendations garner substantial media attention—and therefore might affect women's screening perceptions and behaviors—but to date analyses of such media coverage have focused on single publicized announcements.

Methods

To assess whether media coverage of mammography screening recommendations has evolved, we conducted a content analysis of televised news from four discrete media events from 2009 to 2016, all of which focused on publicized screening recommendations from the U.S. Preventive Services Task Force and American Cancer Society (N = 364 stories).

Results

Media coverage of mammography screening recommendations has featured persistent messages of conflict and/or controversy over time. The evolution of controversy was also reflected in shifts in the relative attention given to mammography screening's risks and benefits, with consistent and, in some cases, heightened attention to screening's risks during more recent media events. Overall, the accuracy of media coverage improved over time.

Conclusions

Results underscore the continued prevalence of conflicting and/or controversial information about mammography screening in the public information environment. Cumulative exposure to such messages could influence women's decision making around screening and trust in cancer prevention recommendations. Strategies are needed to better equip all women (and particularly underserved women) to negotiate mammography controversy and weigh the benefits and risks of screening.  相似文献   
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Maintaining quality, competitiveness and innovation in global health technology is a constant challenge for manufacturers, while affordability, access and equity are challenges for governments and international agencies. In this paper we discuss these issues with reference to rapid diagnostic tests for malaria. Strategies to control and eliminate malaria depend on early and accurate diagnosis. Rapid diagnostic tests for malaria require little training and equipment and can be performed by non-specialists in remote settings. Use of these tests has expanded significantly over the last few years, following recommendations to test all suspected malaria cases before treatment and the implementation of an evaluation programme to assess the performance of the malaria rapid diagnostic tests. Despite these gains, challenges exist that, if not addressed, could jeopardize the progress made to date. We discuss recent developments in rapid diagnostic tests for malaria, highlight some of the challenges and provide suggestions to address them.  相似文献   
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The γ-aminobutyric acid (GABA) system has been proposed as a target for novel antidepressant and anxiolytic treatments. Emerging evidence suggests that gabapentin (GBP), an anticonvulsant drug that significantly increases brain GABA levels, is effective in the treatment of anxiety disorders. The current study was designed to measure prefrontal and occipital GABA levels in medication-free healthy subjects after taking 0 mg, 150 mg and 300 mg GBP. Subjects were scanned on a 3T scanner using a transmit-receive head coil that provided a relatively homogenous radiofrequency field to obtain spectroscopy measurement in the medial prefrontal (MPFC) and occipital cortex (OCC). There was no dose-dependent effect of GBP on GABA levels in the OCC or MPFC. There was also no effect on Glx, choline or N-acetyl-aspartate concentrations. The previously reported finding of increased GABA levels after GBP treatment is not evident for healthy subjects at the dose of 150 and 300 mg. As a result, if subjects are scanned on a 3T scanner, low dose GPB is not useful as an experimental challenge agent on the GABA system.  相似文献   
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Background: Arsenic (III) methyltransferase (AS3MT) has been related to urine arsenic metabolites in association studies. Other genes might also play roles in arsenic metabolism and excretion.Objective: We evaluated genetic determinants of urine arsenic metabolites in American Indian adults from the Strong Heart Study (SHS).Methods: We evaluated heritability of urine arsenic metabolites [percent inorganic arsenic (%iAs), percent monomethylarsonate (%MMA), and percent dimethylarsinate (%DMA)] in 2,907 SHS participants with urine arsenic measurements and at least one relative within the cohort. We conducted a preliminary linkage analysis in a subset of 487 participants with available genotypes on approximately 400 short tandem repeat markers using a general pedigree variance component approach for localizing quantitative trait loci (QTL).Results: The medians (interquartile ranges) for %iAs, %MMA, and %DMA were 7.7% (5.4–10.7%), 13.6% (10.5–17.1%), and 78.4% (72.5–83.1%), respectively. The estimated heritability was 53% for %iAs, 50% for %MMA, and 59% for %DMA. After adjustment for sex, age, smoking, body mass index, alcohol consumption, region, and total urine arsenic concentrations, LOD [logarithm (to the base of 10) of the odds] scores indicated suggestive evidence for genetic linkage with QTLs influencing urine arsenic metabolites on chromosomes 5 (LOD = 2.03 for %iAs), 9 (LOD = 2.05 for %iAs and 2.10 for %MMA), and 11 (LOD = 1.94 for %iAs). A peak for %DMA on chromosome 10 within 2 Mb of AS3MT had an LOD of 1.80.Conclusions: This population-based family study in American Indian communities supports a genetic contribution to variation in the distribution of arsenic metabolites in urine and, potentially, the involvement of genes other than AS3MT.  相似文献   
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