New embedding medium for sectioning undecalcified bone

Methylmethacrylate (MMA) is the most commonly used embedding medium for sectioning undecalcified bone; however, a number of problems exist with its use in a research laboratory. MMA requires a long infiltration time and temperature control, and it reacts with many polymers. We used Kleer Set resin? as an alternative embedding medium for sectioning undecalcified bone specimens. Fluorochrome labeled bone specimens were sectioned transversely using a ground section technique and longitudinally on a sledge macrotome. The slides were viewed using both transmitted light and epifluorescence microscopy. High quality sections were obtained using Kleer Set resin? for both sectioning techniques. We have shown that this new embedding medium is simpler, safer, quicker to use and does not interfere with visualization of fluorochromes.     

Institutional review boards' use and understanding of certificates of confidentiality

Certificates of Confidentiality, issued by agencies of the U.S. government, are regarded as an important tool for meeting ethical and legal obligations to safeguard research participants' privacy and confidentiality. By shielding against forced disclosure of identifying data, Certificates are intended to facilitate research on sensitive topics critical to the public's health. Although Certificates are potentially applicable to an extensive array of research, their full legal effect is unclear, and little is known about stakeholders' views of the protections they provide. To begin addressing this challenge, we conducted a national survey of institutional review board (IRB) chairs, followed by telephone interviews with selected chairs, to learn more about their familiarity with and opinions about Certificates; their institutions' use of Certificates; policies and practices concerning when Certificates are required or recommended; and the role Certificates play in assessments of research risk. Overall, our results suggest uncertainty about Certificates among IRB chairs. On most objective knowledge questions, most respondents chose the incorrect answer or 'unsure'. Among chairs who reported more familiarity with Certificates, composite opinion scores calculated based on five survey questions were evenly distributed among positive, neutral/middle, and negative views. Further, respondents expressed a variety of ideas about the appropriate use of Certificates, what they are intended to protect, and their effect on research risk. Nevertheless, chairs who participated in our study commonly viewed Certificates as a potentially valuable tool, frequently describing them as an 'extra layer' of protection. These findings lead to several practical observations concerning the need for more stakeholder education about Certificates, consideration of Certificates for a broader range of studies, the importance of remaining vigilant and using all tools available to protect participants' confidentiality, and the need for further empirical investigation of Certificates' effect on researchers and research participants.     

Blood groups and protein polymorphisms in five goat breeds (Capra hircus)

Data on allele frequencies at six red cell blood group systems and three blood protein polymorphic loci in five goat breeds are reported. Two blood proteins, albumin and carbonic anhy-drase, were not found to be polymorphic. The B blood group system of goats, like its homologue in cattle and sheep, is highly complex. At least 44 B phenogroups (haplotypes) have been distinguished in this study. Based on the variation in allele frequencies between breeds, genetic distances were calculated. The distances estimated by four different methods were in close agreement with data from the history and geographic origins of the breeds examined.     

High content image analysis for human H4 neuroglioma cells exposed to CuO nanoparticles

Background  

High content screening (HCS)-based image analysis is becoming an important and widely used research tool. Capitalizing this technology, ample cellular information can be extracted from the high content cellular images. In this study, an automated, reliable and quantitative cellular image analysis system developed in house has been employed to quantify the toxic responses of human H4 neuroglioma cells exposed to metal oxide nanoparticles. This system has been proved to be an essential tool in our study.     

Parent perspectives on pediatric genetic research and implications for genotype-driven research recruitment

As genetic research is increasingly conducted in children, it is important to understand how parents make decisions about enrolling their children and what they think about receiving their children's genetic research results. We conducted semi-structured phone interviews with 23 parents of children enrolled in genetic studies of autism or diabetes. Qualitative thematic analysis focused on two important components of genetic research and genotype-driven recruitment: participation in genetic research and return of results. Our findings suggest that parents' preferences and perspectives may be specific to their child's disease and the needs of the family as a whole. Assessing the expectations of target research populations will be beneficial for developing best practices for pediatric genetic research, return of results, and genotype-driven recruitment.     

Microbial Transport, Survival, and Succession in a Sequence of Buried Sediments

Abstract Two chronosequences of unsaturated, buried loess sediments, ranging in age from <10,000 years to >1 million years, were investigated to reconstruct patterns of microbial ecological succession that have occurred since sediment burial. The relative importance of microbial transport and survival to succession was inferred from sediment ages, porewater ages, patterns of abundance (measured by direct counts, counts of culturable cells, and total phospholipid fatty acids), activities (measured by radiotracer and enzyme assays), and community composition (measured by phospholipid fatty acid patterns and Biolog substrate usage). Core samples were collected at two sites 40 km apart in the Palouse region of eastern Washington State, near the towns of Washtucna and Winona. The Washtucna site was flooded multiple times during the Pleistocene by glacial outburst floods; the Winona site elevation is above flood stage. Sediments at the Washtucna site were collected from near surface to 14.9 m depth, where the sediment age was approximately 250 ka and the porewater age was 3700 years; sample intervals at the Winona site ranged from near surface to 38 m (sediment age: approximately 1 Ma; porewater age: 1200 years). Microbial abundance and activities declined with depth at both sites; however, even the deepest, oldest sediments showed evidence of viable microorganisms. Same-age sediments had equal quantities of microorganisms, but different community types. Differences in community makeup between the two sites can be attributed to differences in groundwater recharge and paleoflooding. Estimates of the microbial community age can be constrained by porewater and sediment ages. In the shallower sediments (<9 m at Washtucna, <12 m at Winona), the microbial communities are likely similar in age to the groundwater; thus, microbial succession has been influenced by recent transport of microorganisms from the surface. In the deeper sediments, the populations may be considerably older than the porewater ages, since microbial transport is severely restricted in unsaturated sediments. This is particularly true at the Winona site, which was never flooded.