35 research outputs found
The Grizzly, November 16, 1984
College Acquires New Properties • Crime and Punishment: The New System • Officials Seek Return of Missing Air Masks • Editorial: Force Feeding the Student Body • Letters: Campus Sage Defends Lever Pullers; Group Claims Silent Coup • Study Abroad: A Student\u27s Trip to Scotland • Steady GPA Increase for Math and Poli Sci • Shorts: Pops Concert Scheduled; Shyness Workshop; Three Students Receive Award • Gridders Defeat Dickinson, 45-14 • X-Country Runner Earns Trip to Nationals • Swimmin\u27 women....and the Mermen • CPA Urges Students to Consider Optionshttps://digitalcommons.ursinus.edu/grizzlynews/1128/thumbnail.jp
Widespread Epigenetic Abnormalities Suggest a Broad DNA Methylation Erasure Defect in Abnormal Human Sperm
Male-factor infertility is a common condition, and etiology is unknown for a high proportion of cases. Abnormal epigenetic programming of the germline is proposed as a possible mechanism compromising spermatogenesis of some men currently diagnosed with idiopathic infertility. During germ cell maturation and gametogenesis, cells of the germ line undergo extensive epigenetic reprogramming. This process involves widespread erasure of somatic-like patterns of DNA methylation followed by establishment of sex-specific patterns by de novo DNA methylation. Incomplete reprogramming of the male germ line could, in theory, result in both altered sperm DNA methylation and compromised spermatogenesis.We determined concentration, motility and morphology of sperm in semen samples collected by male members of couples attending an infertility clinic. Using MethyLight and Illumina assays we measured methylation of DNA isolated from purified sperm from the same samples. Methylation at numerous sequences was elevated in DNA from poor quality sperm.This is the first report of a broad epigenetic defect associated with abnormal semen parameters. Our results suggest that the underlying mechanism for these epigenetic changes may be improper erasure of DNA methylation during epigenetic reprogramming of the male germ line
Priorities for synthesis research in ecology and environmental science
ACKNOWLEDGMENTS We thank the National Science Foundation grant #1940692 for financial support for this workshop, and the National Center for Ecological Analysis and Synthesis (NCEAS) and its staff for logistical support.Peer reviewedPublisher PD
Priorities for synthesis research in ecology and environmental science
ACKNOWLEDGMENTS We thank the National Science Foundation grant #1940692 for financial support for this workshop, and the National Center for Ecological Analysis and Synthesis (NCEAS) and its staff for logistical support.Peer reviewedPublisher PD
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Emergency medicine residency fact board: Why our attempt to encourage on-shift learning failed
Recommended from our members
Virtual Simulation-Based Workshop for Addressing Patient Discrimination Against Trainees
Recommended from our members
Emergency medicine residency fact board: Why our attempt to encourage on-shift learning failed.
Residents commonly feel that a lack of time is a significant barrier in keeping up-to-date with both medical knowledge and literature. In this study, we addressed that barrier by placing an iPad-based live fact feed in the resident workroom of our emergency department, therefore allowing for passive learning while on shift. We hypothesized that residents with access to the live feed would score higher on monthly post-curriculum block exams. We ended up finding that the residents actually prefer a more active approach to learning and that many more people in the emergency department other than the residents benefitted from the fact board
Patterns of Epithelial Cell Invasion by Different Species of the Burkholderia cepacia Complex in Well-Differentiated Human Airway Epithelia
Burkholderia cepacia has emerged as a serious respiratory pathogen in cystic fibrosis (CF) patients. The clinical course of B. cepacia infections is variable, but ∼20% of patients eventually succumb to the cepacia syndrome, which is characterized as a fatal necrotizing pneumonia with bacteremia. The mechanisms that permit B. cepacia to cause bacteremia are not yet known but probably involve sequential penetration of airway barriers. This study evaluated the abilities of different species of the B. cepacia complex, including a strain from the ET12 lineage (BC-7, genomovar III, cblA(+)), which is associated with most cepacia syndrome fatalities among CF populations, a genomovar IV strain (HI2258), and a genomovar II strain (J-1) to penetrate polarized, well-differentiated human airway epithelial cell cultures. As revealed by light and electron microscopy, all three B. cepacia strains tested circumvented the mechanical barriers of mucus and ciliary transport to penetrate the airway epithelium but they used different routes. The BC-7 strain (genomovar III) formed biofilms in close proximity to the apical cell surface, followed by invasion and destruction of epithelial cells. This process involved disruption of the glycocalyx and rearrangements of the actin cytoskeleton. The HI2258 strain (genomovar IV) did not form biofilms, and the majority of bacteria that penetrated the epithelium were located between epithelial cells, suggesting paracytosis. Strain J-1 penetrated the epithelium both by cell destruction and paracytosis. These studies suggest that the distinct invasion pathways employed by B. cepacia may account for differences in virulence between B. cepacia genomovars