Integrin α_IIbβ₃ activation and clustering in minimal synthetic cells

Platelet adhesion and activation are mediated by integrin αIIbβ3 clustering, which is crucial for the hemostatic function of platelets. In an activated state, integrins provide the connection between the extracellular matrix and the actin cytoskeleton through a variety of cytoplasmic proteins, such as talin. Here, droplet-based microfluidics is applied to generate cell-sized giant unilamellar vesicles (GUVs) with a defined molecular composition to quantify the adhesion of integrin αIIbβ3-containing protocells in relation to the number of integrin–talin head domain (THD) complexes. Furthermore, it is shown that THD induces integrin clustering in protocells adhering to fibrinogen. The formation of this molecular link, which has, so far, only been observed in vivo, is an essential step in synthetic cell design to recapitulate integrin-mediated bidirectional signaling across the membrane. These results pave the way for further quantitative investigations of protein–protein interactions between integrins and associated proteins and their assembly within such defined, but complex, synthetic cells. An essential future step to mimic the complex interaction between cells and their environment will be to combine synthetic approaches with peptide chemistry to guide the molecular mechanisms involved in integrin binding and activation

Palladium nanoparticles by electrospinning from poly(acrylonitrile-co-acrylic acid)-PdCl2 solutions. Relations between preparation conditions, particle size, and catalytic activity

Catalytic palladium (Pd) nanoparticles on electrospun copolymers of acrylonitrile and acrylic acid (PAN-AA) mats were produced via reduction of PdCl2 with hydrazine. Fiber mats were electrospun from homogeneous solutions of PAN-AA and PdCl2 in dimethylformamide (DMF). Pd cations were reduced to Pd metals when fiber mats were treated in an aqueous hydrazine solution at room temperature. Pd atoms nucleate and form small crystallites whose sizes were estimated from the peak broadening of X-ray diffraction peaks. Two to four crystallites adhere together and form agglomerates. Agglomerate sizes and fiber diameters were determined by scanning and transmission electron microscopy. Spherical Pd nanoparticles were dispersed homogeneously on the electrospun nanofibers. The effects of copolymer composition and amount of PdCl2 on particle size were investigated. Pd particle size mainly depends on the amount of acrylic acid functional groups and PdCl2 concentration in the spinning solution. Increasing acrylic acid concentration on polymer chains leads to larger Pd nanoparticles. In addition, Pd particle size becomes larger with increasing PdCl2 concentration in the spinning solution. Hence, it is possible to tune the number density and the size of metal nanoparticles. The catalytic activity of the Pd nanoparticles in electrospun mats was determined by selective hydrogenation of dehydrolinalool (3,7-dimethyloct-6- ene-1-yne-3-ol, DHL) in toluene at 90 °C. Electrospun fibers with Pd particles have 4.5 times higher catalytic activity than the current Pd/Al2O3 catalyst

Sampling Local Fungal Diversity in an Undergraduate Laboratory using DNA Barcoding

Traditional methods for fungal species identification require diagnostic morphological characters and are often limited by the availability of fresh fruiting bodies and local identification resources. DNA barcoding offers an additional method of species identification and is rapidly developing as a critical tool in fungal taxonomy. As an exercise in an undergraduate biology course, we identified 9 specimens collected from the Hendrix College campus in Conway, Arkansas, USA to the genus or species level using morphology. We report that DNA barcoding targeting the internal transcribed spacer (ITS) region supported several of our taxonomic determinations and we were able to contribute 5 ITS sequences to GenBank that were supported by vouchered collection information. We suggest that small-scale barcoding projects are possible and that they have value for documenting fungal diversity

Moving lessons: teaching sociology through embodied learning in the HE classroom

This chapter outlines an approach to classroom teaching that makes use of physical movement alongside more traditional lecturing methods when delivering lessons on abstract theoretical material. It develops the notion of embodied learning as a 'physical metaphor', outlining some examples of this practice that we have used in our recent work with a class of first year undergraduates. We argue that conceptualising students as embodied subjects, whose capacity to learn extends through and beyond their physical selves, educators are able to enhance classroom delivery by diversifying teaching activities and creating opportunities for enjoyable and memorable learning experiences. We advocate the reflexive, contextually-sensitive and level- appropriate use of this method, arguing that despite some limitations it can animate students' understanding of academic ideas in uniquely personalised ways

Conservation risk of Batrachochytrium salamandrivorans to endemic lungless salamanders

The emerging fungal pathogen, Batrachochytrium salamandrivorans (Bsal ), is a significant conservation threat to salamander biodiversity in Europe, although its potential to affect North American species is poorly understood. We tested the susceptibility of two genera (Eurycea and Pseudotriton ) and three populations of lungless salamanders (Plethodontidae ) to Bsal . All species became infected with Bsal and two (Pseudotriton ruber and Eurycea wilderae ) developed chytridiomycosis. We also documented that susceptibility of E. wilderae differed among populations. Regardless of susceptibility, all species reduced feeding when exposed to Bsal at the highest zoospore dose, and P. ruber and one population of E. wilderae used cover objects less. Our results indicate that Bsal invasion in eastern North America could have significant negative impacts on endemic lungless salamander populations. Future conservation efforts should include surveillance for Bsal in the wild and in captivity, and championing legislation that requires and subsidizes pathogen‐free trade of amphibians

Conservation risk of Batrachochytrium salamandrivorans to endemic lungless salamanders

The emerging fungal pathogen, Batrachochytrium salamandrivorans (Bsal), is a significant conservation threat to salamander biodiversity in Europe, although its potential to affect North American species is poorly understood. We tested the susceptibility of two genera (Eurycea and Pseudotriton) and three populations of lungless salamanders (Plethodontidae) to Bsal. All species became infected with Bsal and two (Pseudotriton ruber and Eurycea wilderae) developed chytridiomycosis. We also documented that susceptibility of E. wilderae differed among populations. Regardless of susceptibility, all species reduced feeding when exposed to Bsal at the highest zoospore dose, and P. ruber and one population of E. wilderae used cover objects less. Our results indicate that Bsal invasion in eastern North America could have significant negative impacts on endemic lungless salamander populations. Future conservation efforts should include surveillance for Bsal in the wild and in captivity, and championing legislation that requires and subsidizes pathogen-free trade of amphibians

Life\u27s Simple 7 and Incident Heart Failure: The Multi‐Ethnic Study of Atherosclerosis

Background The American Heart Association introduced the Life\u27s Simple 7 (LS7) metrics to assess and promote cardiovascular health. We sought to examine the association between the LS7 metrics and incident heart failure (HF) in a multiethnic cohort. Methods and Results We analyzed data from 6506 participants of the Multi‐Ethnic Study of Atherosclerosis free of cardiovascular disease at baseline. The LS7 metrics (smoking, physical activity, body mass index, diet, blood pressure, total cholesterol, and blood glucose) were graded on a scale of 0 to 2, with 2 indicating “ideal” status, 1 “intermediate” status, and 0 “poor” status. Points were summed, thus the LS7 score ranged from 0 to 14. Cox proportional hazard ratios and incidence rates of HF per 1000 person‐years were calculated. During a median follow‐up of 12.2 years, 262 (4%) participants developed HF. Incidence of HF decreased as the number of ideal LS7 metrics increased; 5.9 per 1000 person‐years for participants with 0 to 1 ideal metrics and 0.6 per 1000 person‐years for those with 6 to 7 ideal metrics. Compared with inadequate scores (0–8 points), hazard ratios for HF were 0.57 (0.43–0.76) and 0.31 (0.19–0.49) for average (9–10 points) and optimal (11–14 points) scores, respectively. A similar pattern was observed when the results were stratified by 4 racial/ethnic groups: white, Chinese American, black, and Hispanic. Conclusions A lower risk of HF with more favorable LS7 status regardless of race/ethnicity suggests that efforts to achieve ideal cardiovascular health may reduce the burden of HF, a major source of morbidity and mortality