Single Molecule Translation Imaging Visualizes the Dynamics of Local β-Actin Synthesis in Retinal Axons

Local mRNA translation occurs in growing axons enabling precise control of the proteome in response to signals. To measure quantitatively the spatiotemporal dynamics of protein synthesis in growth cones, we further developed a technique for single molecule translation imaging (SMTI). We report that Netrin-1 triggers a burst of β-actin synthesis at multiple non-repetitive sites, particularly in the periphery. The response is remarkably rapid starting within 20 seconds of cue application.This work was supported by grants from the Leverhulme Trust, the Engineering and Physical Sciences Research Council, UK (grant EP/H018301/1), the Medical Research Council (grant MR/K015850/1, and MR/K02292X/1), the Wellcome Trust (089703/Z/09/Z) (C.F.K.), Sir Edward Youde Memorial Fund, Croucher Foundation, Cambridge Trust (H.H.W.) Gates Cambridge Scholarship (J.Q.L.), Wellcome Trust Studentship (V.U.), European Research Council Advanced Grant (322817), the Wellcome Trust (085314/Z/08/Z) (C.E.H.)

Polarity-sensitive probes for superresolution stimulated emission depletion microscopy

The lateral organization of molecules in the cellular plasma membrane plays an important role in cellular signaling. A critical parameter for membrane molecular organization is how the membrane lipids are packed (or ordered). Polarity sensitive dyes are powerful tools to characterize such lipid membrane order, employing for example confocal and two-photon microscopy. The investigation of potential lipid nanodomains, however, requires the use of super resolution microscopy. Here, we test the performance of the polarity sensitive membrane dyes Di-4-ANEPPDHQ, Di-4-AN(F)EPPTEA and NR12S in super resolution STED microscopy. Measurements on cell-derived membrane vesicles, in the plasma membrane of live cells, and on single virus particles show the high potential of these dyes for probing nanoscale membrane heterogeneity

Polarity-sensitive probes for superresolution stimulated emission depletion microscopy

The lateral organization of molecules in the cellular plasma membrane plays an important role in cellular signaling. A critical parameter for membrane molecular organization is how the membrane lipids are packed. Polarity-sensitive dyes are powerful tools to characterize such lipid membrane order, employing, for example, confocal and two-photon microscopy. The investigation of potential nanodomains, however, requires the use of superresolution microscopy. Here, we test the performance of the polarity-sensitive membrane dyes Di-4-ANEPPDHQ, Di-4-AN(F)EPPTEA, and NR12S in superresolution stimulated emission depletion microscopy. Measurements on cell-derived membrane vesicles, in the plasma membrane of live cells, and on single virus particles, show the high potential of these dyes for probing nanoscale membrane heterogeneity

Prediction of chronic inflammation for inhaled particles: the impact of material cycling and quarantining in the lung epithelium

On a daily basis, people are exposed to a multitude of health-hazardous airborne particulate matter with notable deposition in the fragile alveolar region of the lungs. Hence, there is a great need for identification and prediction of material-associated diseases, currently hindered due to the lack of in-depth understanding of causal relationships, in particular between acute exposures and chronic symptoms. By applying advanced microscopies and omics to in vitro and in vivo systems, together with in silico molecular modeling, it is determined herein that the long-lasting response to a single exposure can originate from the interplay between the newly discovered nanomaterial quarantining and nanomaterial cycling between different lung cell types. This new insight finally allows prediction of the spectrum of lung inflammation associated with materials of interest using only in vitro measurements and in silico modeling, potentially relating outcomes to material properties for a large number of materials, and thus boosting safe-by-design-based material development. Because of its profound implications for animal-free predictive toxicology, this work paves the way to a more efficient and hazard-free introduction of numerous new advanced materials into our lives

Interventions in the management of infection in the foot in diabetes: a systematic review

The expert panel on diabetic foot infection (DFI) of the International Working Group on the Diabetic Foot conducted a systematic review seeking all published reports relating to any type of treatment for infection of the foot in persons with diabetes published as of 30 June 2014. This review, conducted with both PubMed and EMBASE, was used to update an earlier one undertaken on 30 June 2010 using the same search string. Eligible publications included those that had outcome measures reported for both a treated and a control population that were managed either at the same time, or as part of a before-and-after case design. We did not include studies that contained only information related to definition or diagnosis, but not treatment, of DFI. The current search identified just seven new articles meeting our criteria that were published since the 33 identified with the previous search, making a total of 40 articles from the world literature. The identified articles included 37 randomised controlled trials (RCTs) and three cohort studies with concurrent controls, and included studies on the use of surgical procedures, topical antiseptics, negative pressure wound therapy and hyperbaric oxygen. Among the studies were 15 RCTs that compared outcomes of treatment with new antibiotic preparations compared with a conventional therapy in the management of skin and soft tissue infection. In addition, 10 RCTs and 1 cohort study compared different treatments for osteomyelitis in the diabetic foot. Results of comparisons of different antibiotic regimens generally demonstrated that newly introduced antibiotic regimens appeared to be as effective as conventional therapy (and also more cost-effective in one study), but one study failed to demonstrate non-inferiority of a new antibiotic compared with that of a standard agent. Overall, the available literature was both limited in both the number of studies and the quality of their design. Thus, our systematic review revealed little evidence upon which to make recommendations for treatment of DFIs. There is a great need for further well-designed trials that will provide robust data upon which to make decisions about the most appropriate treatment of both skin and soft tissue infection and osteomyelitis in diabetic patients

Single cell temperature probed by Eu 3 doped TiO2 nanoparticles luminescence

Abstract Temperature is a critical parameter in biology, affecting the speed of reactions that occur in living systems. Nevertheless, measuring temperature with subcellular resolution (micrometric scale) and reliability remains a challenge to overcome. In this perspective, luminescence nanothermometry is a non‐contact technique which aims to measure temperature with a sub‐micrometric spatial resolution through the use of nanomaterials whose luminescence is affected solely by changes in temperature. Here, TiO2 nanoparticles doped with Eu+3 ions (Eu+3‐TiO2) are used for sensing temperature differences within single living cells. XRD, XPS, SEM, TEM and NEXAFS analysis allow the determination of the physicochemical characteristics of the Eu+3‐TiO2 nanoparticles and, the variation of the luminescence intensity of the Eu+3‐TiO2 nanoparticles with their temperature is investigated. The successful internalization of Eu+3‐TiO2 nanoparticles in different types of cells is observed. The luminescence of nanoparticles internalized in L929 fibroblast cells is measured when the system is heated in a biological relevant temperature range. Making use of an appropriate calibration curve the temperature variation inside the cells is determined with sensitivity of 0.5 K per 1% of luminosity change when heated