TheamnGene Product Is Required in Extraembryonic Tissues for the Generation of Middle Primitive Streak Derivatives

AbstractThe primitive streak is the defining feature of the gastrulating mouse embryo. Currently, little is known in the mouse about the mechanisms that mediate the assembly of the primitive streak or about the signaling pathways that specify the different types of mesoderm and endoderm generated from the streak. To gain insight into primitive streak assembly and function, we have conducted a detailed phenotypic characterization ofamnionless,a transgene-induced insertional mouse mutation that arrests embryonic development during gastrulation. Our histological and molecular analyses, when examined in the context of the mouse gastrula fate map, lead to the model that middle streak formation is specifically impaired in theamnionlessmutant. Significantly, these observations argue that the formation of the middle streak is mediated by a pathway that is genetically separable from those that direct the specification of the distal and proximal streak regions. Intriguingly, our findings from wt ES cell ↔amnionless−/−blastocyst chimeras indicate that this proposed separate pathway for middle streak formation is dependent onamnionlessgene functions in the visceral endoderm

PD11-10 A 10-ITEM CHECKLIST CHECKLIST IMPROVES REPORTING OF CRITICAL PROCEDURAL ELEMENTS DURING TRANSURETHRAL RESECTION OF BLADDER TUMOR

Previous studies have demonstrated significant variation in recurrence rates after transurethral resection of bladder tumor, likely due to differences in surgical quality. We sought to create a framework to define, measure and improve the quality of transurethral resection of bladder tumor using a surgical checklist. We formed a multi-institutional group of urologists with expertise with bladder cancer and identified 10 critical items that should be performed during every high quality transurethral bladder tumor resection. We prospectively implemented a 10-item checklist into practice and reviewed the operative reports of such resections performed before and after implementation. Results at all institutions were combined in a meta-analysis to estimate the overall change in the mean number of items documented. The operative notes for 325 transurethral bladder tumor resections during checklist use were compared to those for 428 performed before checklist implementation. Checklist use increased the mean number of items reported from 4.8 to 8.0 per resection, resulting in a mean increase of 3.3 items (95% CI 1.9–4.7) on meta-analysis. With the checklist the percentage of reports that included all 10 items increased from 0.5% to 27% (p <0.0001). Surgeons who reported more checklist items tended to have a slightly higher proportion of biopsies containing muscle, although not at conventional significance (p = 0.062). The use of a 10-item checklist during transurethral resection of bladder tumor improved the reporting of critical procedural elements. Although there was no clear impact on the inclusion of muscle in the specimen, checklist use may enhance surgeon attention to important aspects of the procedure and be a lever for quality improvement

Surface Ocean CO2 Atlas (SOCAT) V2

The Surface Ocean CO2 Atlas (SOCAT), an activity of the international marine carbon research community, provides access to synthesis and gridded fCO2 (fugacity of carbon dioxide) products for the surface oceans. Version 2 of SOCAT is an update of the previous release (version 1) with more data (increased from 6.3 million to 10.1 million surface water fCO2 values) and extended data coverage (from 1968-2007 to 1968-2011). The quality control criteria, while identical in both versions, have been applied more strictly in version 2 than in version 1. The SOCAT website (http://www.socat.info/) has links to quality control comments, metadata, individual data set files, and synthesis and gridded data products. Interactive online tools allow visitors to explore the richness of the data. Applications of SOCAT include process studies, quantification of the ocean carbon sink and its spatial, seasonal, year-to-year and longerterm variation, as well as initialisation or validation of ocean carbon models and coupled climate-carbon models