8,844 research outputs found
Inhibition of gap junction and adherens junction assembly by connexin and A-CAM antibodies
We examined the roles of the extracellular domains of a gap junction protein and a cell adhesion molecule in gap junction and adherens junction formation by altering cell interactions with antibody Fab fragments. Using immunoblotting and immunocytochemistry we demonstrated that Novikoff cells contained the gap junction protein, connexin43 (Cx43), and the cell adhesion molecule, A-CAM (N-cadherin). Cells were dissociated in EDTA, allowed to recover, and reaggregated for 60 min in media containing Fab fragments prepared from a number of antibodies. We observed no cell-cell dye transfer 4 min after microinjection in 90% of the cell pairs treated with Fab fragments of antibodies for the first or second extracellular domain of Cx43, the second extracellular domain of connexin32 (Cx32) or A-CAM. Cell-cell dye transfer was detected within 30 s in cell pairs treated with control Fab fragments (pre-immune serum, antibodies to the rat major histocompatibility complex or the amino or carboxyl termii of Cx43). We observed no gap junctions by freeze-fracture EM and no adherens junctions by thin section EM between cells treated with the Fab fragments that blocked cell-cell dye transfer. Gap junctions were found on approximately 50% of the cells in control samples using freeze-fracture EM. We demonstrated with reaggregated Novikoff cells that: (a) functional interactions of the extracellular domains of the connexins were necessary for the formation of gap junction channels; (b) cell interactions mediated by A-CAM were required for gap junction assembly; and (c) Fab fragments of antibodies for A-CAM or connexin extracellular domains blocked adherens junction formation
Everyone should be able to choose how they get around : How Topeka, Kansas, passed a complete streets resolution
BACKGROUND: Regular physical activity can help prevent chronic diseases, yet only half of US adults meet national physical activity guidelines. One barrier to physical activity is a lack of safe places to be active, such as bike paths and sidewalks. Complete Streets, streets designed to enable safe access for all users, can help provide safe places for activity. COMMUNITY CONTEXT: This community case study presents results from interviews with residents and policymakers of Topeka, Kansas, who played an integral role in the passage of a Complete Streets resolution in 2009. It describes community engagement processes used to include stakeholders, assess existing roads and sidewalks, and communicate with the public and decision-makers. METHODS: Key informant interviews were conducted with city council members and members of Heartland Healthy Neighborhoods in Topeka to learn how they introduced a Complete Streets resolution and the steps they took to ensure its successful passage in the City Council. Interviews were recorded, transcribed, and analyzed by using focused-coding qualitative analysis. OUTCOME: Results included lessons learned from the process of passing the Complete Streets resolution and advice from participants for other communities interested in creating Complete Streets in their communities. INTERPRETATION: Lessons learned can apply to other communities pursuing Complete Streets. Examples include clearly defining Complete Streets; educating the public, advocates, and decision-makers about Complete Streets and how this program enhances a community; building a strong and diverse network of supporters; and using stories and examples from other communities with Complete Streets to build a convincing case
Building capacity for dissemination and implementation research: One university’s experience
Abstract Background While dissemination and implementation (D&I) science has grown rapidly, there is an ongoing need to understand how to build and sustain capacity in individuals and institutions conducting research. There are three inter-related domains for capacity building: people, settings, and activities. Since 2008, Washington University in St. Louis has dedicated significant attention and resources toward building D&I research capacity. This paper describes our process, challenges, and lessons with the goal of informing others who may have similar aims at their own institution. Activities An informal collaborative, the Washington University Network for Dissemination and Implementation Research (WUNDIR), began with a small group and now has 49 regular members. Attendees represent a wide variety of settings and content areas and meet every 6 weeks for half-day sessions. A logic model organizes WUNDIR inputs, activities, and outcomes. A mixed-methods evaluation showed that the network has led to new professional connections and enhanced skills (e.g., grant and publication development). As one of four, ongoing, formal programs, the Dissemination and Implementation Research Core (DIRC) was our first major component of D&I infrastructure. DIRC’s mission is to accelerate the public health impact of clinical and health services research by increasing the engagement of investigators in later stages of translational research. The aims of DIRC are to advance D&I science and to develop and equip researchers with tools for D&I research. As a second formal component, the Washington University Institute for Public Health has provided significant support for D&I research through pilot projects and a small grants program. In a third set of formal programs, two R25 training grants (one in mental health and one in cancer) support post-doctoral scholars for intensive training and mentoring in D&I science. Finally, our team coordinates closely with D&I functions within research centers across the university. We share a series of challenges and potential solutions. Conclusion Our experience in developing D&I research at Washington University in St. Louis shows how significant capacity can be built in a relatively short period of time. Many of our ideas and ingredients for success can be replicated, tailored, and improved upon by others
Where does the time go? An experimental test of what social media displaces and displaced activities’ associations with affective well-being and quality of day
Drawing from media displacement theory, this article explores which activities are displaced when individuals spend time on social media. Community and undergraduate participants (N = 135) were randomly assigned to five conditions: no change in social media use, or abstinence from social media for 1 week, 2 weeks, 3 weeks, or 4 weeks. Participants completed a daily diary measuring how they spent time each day, affective well-being, and quality of day for 28 days. The results indicate that abstinence from social media increased time spent engaged in seven activities, primarily browsing the Internet, working, childcare, and cooking/cleaning. In addition, associations among psychosocial outcomes and the displaced activities were examined. Time spent working, sleeping, and cooking/cleaning were negatively associated with affective well-being and quality of day. On days participants used social media, minutes of use were negatively associated with quality of day. The results suggest that social media primarily displaces unpleasant or neutral activities
Trends in sexually transmitted infections in general practice 1990-2000: population based study using data from the UK general practice research database
Objective: To describe the contribution of primary care to the
diagnosis and management of sexually transmitted infections in
the United Kingdom, 1990-2000, in the context of increasing
incidence of infections in genitourinary medicine clinics.
Design: Population based study.
Setting: UK primary care.
Participants: Patients registered in the UK general practice
research database.
Main outcome measures: Incidence of diagnosed sexually
transmitted infections in primary care and estimation of the
proportion of major such infections diagnosed in primary care.
Results: An estimated 23.0% of chlamydia cases in women but
only 5.3% in men were diagnosed and treated in primary care
during 1998-2000, along with 49.2% cases of non-specific
urethritis and urethral discharge in men and 5.7% cases of
gonorrhoea in women and 2.9% in men. Rates of diagnosis in
primary care rose substantially in the late 1990s.
Conclusions: A substantial and increasing number of sexually
transmitted infections are diagnosed and treated in primary
care in the United Kingdom, with sex ratios differing from
those in genitourinary medicine clinics. Large numbers of men
are treated in primary care for presumptive sexually
transmitted infections
Pan-squamous genomic profiling stratified by anatomic tumor site and viral association
Background: Squamous cell carcinomas (SCC) have diverse anatomic etiologies but may share common genomic biomarkers. We profiled 7,871 unique SCCs across nine anatomic sites to investigate commonality in genomic alterations (GA), tumor mutational burden (TMB), human papillomavirus (HPV) association, and mutational signatures.
Methods: Tissue from over 8,100 unique SCC samples originating from nine anatomic sites (anogenital (anus, cervix, penis, vagina, vulva), esophagus, head and neck, lung, and skin) were sequenced by hybrid capture-based comprehensive genomic profiling to evaluate GA and TMB. About 3% of non-cutaneous SCC samples had UV signatures, indicative of potential primary site misdiagnoses, and were filtered from the analysis. Detection of HPV, including high-risk strains 16, 18, 31, 33, and 45, was implemented through de novo assembly of non-human sequencing reads and BLASTn comparison against all viral nucleotide sequences in the NCBI database.
Results: The proportion of HPV+ patients by anatomic site varied, with the highest being anal (91%) and cervical (83%). The mutational landscape of each cohort was similar, regardless of anatomic origin, but clustered based on HPV status. The largest differences in GA frequency as stratified by HPV- vs. HPV+ were TP53 (87% vs. 12%), CDKN2A (45% vs. 6%), and PIK3CA (22% vs. 33%). The median TMB in cases originating from HPV-associated sites was similar, regardless of HPV status. Higher median TMB was observed in lung and skin cases, which exhibited significant enrichment of mutational signatures indicative of tobacco- and UV-induced DNA damage, respectively.
Conclusions: HPV+ and HPV- SCC populations have distinct genomic profiles and, for the latter, anatomic site is correlated with TMB distribution, secondary to associated carcinogen exposure. As such, biomarkers such as TMB and UV signature can provide unexpected insight into site of origin misdiagnoses and may correlate with benefit from immune checkpoint inhibitors
Vector bundles on the projective line and finite domination of chain complexes
Finitely dominated chain complexes over a Laurent polynomial ring in one
indeterminate are characterised by vanishing of their Novikov homology. We
present an algebro-geometric approach to this result, based on extension of
chain complexes to sheaves on the projective line. We also discuss the
K-theoretical obstruction to extension.Comment: v1: 11 page
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