ABSTRACT
Microtubule dynamics is regulated by plus end-tracking proteins (+TIPs), which localize to the plus ends of microtubules (MTs). We previously showed that TACC1 and TACC3, members of the transforming acidic coiled-coil protein family, can act as +TIPs to regulate MT dynamics in Xenopus laevis Here we characterize TACC2 as a +TIP that localizes to MT plus ends in front of EB1 and overlapping with TACC1 and TACC3 in multiple embryonic cell types. We also show that TACC2 can promote MT polymerization in mesenchymal cells but not neuronal growth cones, thus displaying cell-type specificity. Structure-function analysis demonstrates that the C-terminal region of TACC2 is both necessary and sufficient to localize to MT plus ends and promote increased rates of MT polymerization, whereas the N-terminal region cannot bind to MT plus ends but can act in a dominant-negative capacity to reduce polymerization rates. Finally, we analyze mRNA expression patterns in Xenopus embryos for each TACC protein and observe neural enrichment of TACC3 expression compared with TACC1 and TACC2, which are also expressed in mesodermal tissues, including somites. Overall these data provide a novel assessment of all three TACC proteins as a family of +TIPs by highlighting the unique attributes of each, as well as their collective characteristics.
Subject(s)
Microtubule-Associated Proteins/metabolism , Nuclear Proteins/metabolism , Transcription Factors/metabolism , Xenopus Proteins/metabolism , Animals , Cell Cycle Proteins/metabolism , Embryonic Development , Gene Expression , Growth Cones/metabolism , Microtubules/metabolism , Polymerization , Protein Domains , Structure-Activity Relationship , Xenopus , Xenopus laevis/genetics , Xenopus laevis/metabolismABSTRACT
This pilot study explored issues important to enrollment in clinical trials by elderly patients. We surveyed and interviewed elderly patients who had been asked to participate in trials. The information covered general attitudes toward research and specific aspects of trial recruitment. Elderly patients had favorable attitudes toward research. This favorable attitude was significantly stronger in men than in women and stronger in Whites than non-Whites but not significantly so. Altruistic motives, physician recommendations, and individual assessment of inconveniences, benefits, and risks of trial participation drove decisions. Elderly patients have positive views of research; however, this will only facilitate trial participation if patients perceive the commitment of enrolling, the potential risks, and possible side effects as reasonable.
Subject(s)
Clinical Trials as Topic/psychology , Patient Selection , Research Subjects/psychology , Aged , Aged, 80 and over , Attitude , Cross-Sectional Studies , Female , Humans , Male , Motivation , Pilot Projects , Sex Factors , White PeopleABSTRACT
Many hospitals use color codes to denote internal (i.e. patient respiratory distress), or external (i.e. natural disasters) emergencies, via public announcement systems. Variations in the codes used by different hospitals can create confusion among providers who may practice in more than one hospital. This study sought to understand emergency code practices in the Delaware Valley region, assess patient and provider knowledge of codes at one hospital in that region, and patient and provider preferences for emergency code standardization and format. Anonymous electronic surveys on procedural knowledge and perspectives of emergency codes were disseminated to hospital staff and patients located at a large regional hospital. Phone interviews were conducted with hospital administration at the regional hospital and other hospitals within a 50-mile radius. The author's research indicates that standardization would be accepted by patients and providers and its lack is considered a barrier to providing high quality care.
