Publications

The ASGE Technology Committee provides reviews of existing, new, or emerging endoscopic technologies that have an impact on the practice of GI endoscopy. Evidence-based methodology is used, by using a MEDLINE literature search to identify pertinent clinical studies on the topic and a MAUDE (U.S. Food and Drug Administration Center for Devices and Radiological Health) database search to identify the reported complications of a given technology. Both are supplemented by accessing the "related articles" feature of PubMed and by scrutinizing pertinent references cited by the identified studies. Controlled clinical trials are emphasized, but in many cases, data from randomized, controlled trials are lacking. In such cases, large case series, preliminary clinical studies, and expert opinions are used. Technical data are gathered from traditional and Web-based publications, proprietary publications, and informal communications with pertinent vendors. Technology Status Evaluation Reports are drafted by 1 or 2 members of the ASGE Technology Committee, reviewed and edited by the committee as a whole, and approved by the Governing Board of the ASGE. When financial guidance is indicated, the most recent coding data and list prices at the time of publication are provided. For this review, the MEDLINE database was searched through August 2009 for articles related to personal protection equipment by using the key words "personal protection equipment" (exp Protective Clothing/ or exp Protective Devices/ or exp Masks/ or exp Occupational Exposure/'') "infection control" paired with "Endoscopy." For the radiation section, the following key words were used: "radiation and endoscopy," "radiation and ERCP," and "radiation safety." For the ergonomics section, the following key words were used: "ergonomics of endoscopy," "endoscopist injury," "medical ergonomics," "endoscopy and musculoskeletal strain," "musculoskeletal injury and endoscopists," "occupational diseases and endoscopy," "cumulative trauma disorder and endoscopy," "repetitive strain injury and endoscopy." Technology Status Evaluation Reports are scientific reviews provided solely for educational and informational purposes. Technology Status Evaluation Reports are not rules and should not be construed as establishing a legal standard of care or as encouraging, advocating, requiring, or discouraging any particular treatment or payment for such treatment.

Two major goals of regenerative medicine are to reproducibly transform adult somatic cells into a pluripotent state and to control their differentiation into specific cell fates. Progress toward these goals would be greatly helped by obtaining a complete picture of the RNA isoforms produced by these cells due to alternative splicing (AS) and alternative promoter selection (APS). To investigate the roles of AS and APS, reciprocal exon-exon junctions were interrogated on a genome-wide scale in differentiating mouse embryonic stem (ES) cells with a prototype Affymetrix microarray. Using a recently released open-source software package named AltAnalyze, we identified 144 genes for 170 putative isoform variants, the majority (67%) of which were predicted to alter protein sequence and domain composition. Verified alternative exons were largely associated with pathways of Wnt signaling and cell-cycle control, and most were conserved between mouse and human. To examine the functional impact of AS, we characterized isoforms for two genes. As predicted by AltAnalyze, we found that alternative isoforms of the gene Serca2 were targeted by distinct microRNAs (miRNA-200b, miRNA-214), suggesting a critical role for AS in cardiac development. Analysis of the Wnt transcription factor Tcf3, using selective knockdown of an ES cell-enriched and characterized isoform, revealed several distinct targets for transcriptional repression (Stmn2, Ccnd2, Atf3, Klf4, Nodal, and Jun) as well as distinct differentiation outcomes in ES cells. The findings herein illustrate a critical role for AS in the specification of ES cells with differentiation, and highlight the utility of global functional analyses of AS.

BACKGROUND

Because racial discrimination is a form of chronic psychological stress that might unfavorably affect health, we examined whether perceived experiences of racism among black women are associated with mortality.

METHODS

We followed 48 924 participants in the Black Women's Health Study (mean age, 40.5 years) for 8 years to assess the risk of all-cause mortality associated with perceived experiences of racism. Subanalyses of cancer and cardiovascular mortality were also conducted. Perceived racism was evaluated by 8 questions about institutionalized racism (unfair treatment on the job, in housing, or by the police) and everyday experiences of racism (eg, others acting as if the woman was not intelligent). We estimated the relative risk of death with Cox proportional hazard models, adjusting for traditional and socioenvironmental risk factors.

RESULTS

During 412 224 person years of follow-up from 1997 to 2005, there were 920 deaths, including 277 due to cancer and 195 due to cardiovascular causes. All-cause mortality was not associated with institutionalized racism (relative risk, 1.0; 95% confidence interval, 0.8-1.2) for the highest category vs the lowest or with everyday racism (relative risk, 0.9; 95% confidence interval, 0.8-1.2) for the highest quartile compared with the lowest. Risk estimates for the highest categories of perceived racism relative to the lowest were greater than 1.0 for cancer deaths and less than 1.0 for cardiovascular disease death but were not statistically significant.

CONCLUSIONS

In this large prospective study of black women, reported experiences of racism were not significantly related to mortality. Longer follow-up of this relatively young cohort and further work is warranted in this complex area of research because continued race/ethnic disparities in mortality are not entirely explained by traditional risk factors.

Mycobacterium tuberculosis is an obligate human pathogen capable of persisting in individual hosts for decades. We sequenced the genomes of 21 strains representative of the global diversity and six major lineages of the M. tuberculosis complex (MTBC) at 40- to 90-fold coverage using Illumina next-generation DNA sequencing. We constructed a genome-wide phylogeny based on these genome sequences. Comparative analyses of the sequences showed, as expected, that essential genes in MTBC were more evolutionarily conserved than nonessential genes. Notably, however, most of the 491 experimentally confirmed human T cell epitopes showed little sequence variation and had a lower ratio of nonsynonymous to synonymous changes than seen in essential and nonessential genes. We confirmed these findings in an additional data set consisting of 16 antigens in 99 MTBC strains. These findings are consistent with strong purifying selection acting on these epitopes, implying that MTBC might benefit from recognition by human T cells.