An alternative placement model for nursing students: discovering new horizons

This paper will explore the use of an alternative placement model and establish how it can be used in conjunction with the Nursing and Midwifery Council (NMC) standards for education and training (2018). Traditionally in nurse education, students were supported on a one to one basis by a qualified nurse mentor in placement. This could be a very intense relationship and could limit placement learning as students were only allocated to areas that have a qualified nurse mentor, exacerbating competing demands on placement capacity to support students. A Higher Education Institute (HEI) trialled an alternative placement model that utilised several healthcare related services traditionally not used for nursing placements. Some of these placements were allocated by the HEI, however students were also responsible for securing a number for themselves. The students were supported with their learning by appropriate healthcare staff in practice but were assessed by academic members of staff at the HEI acting as practice assessors. The project was evaluated positively overall by both students and staff. Students found it to be an empowering experience, which encouraged autonomous practice

Anti-platelet properties of Pim kinase inhibition is mediated through disruption of thromboxane A2 receptor signalling

Pim kinases are upregulated in several forms of cancer, contributing to cell survival and tumour development, but their role in platelet function and thrombotic disease has not been explored. We report for the first time that Pim-1 kinase is expressed in human and mouse platelets. Genetic deletion or pharmacological inhibition of Pim kinase results in reduced thrombus formation but is not associated with impaired haemostasis. Attenuation of thrombus formation was found to be due to inhibition of the thromboxane A2 receptor as effects on platelet function was non-additive to inhibition caused by the cyclooxygenase inhibitor indomethacin or thromboxane A2 receptor antagonist GR32191. Treatment with Pim kinase inhibitors caused reduced surface expression of the thromboxane A2 receptor and resulted in reduced responses to thromboxane A2 receptor agonists, indicating a role for Pim kinase in the regulation of thromboxane A2 receptor function. Our research identifies a novel, Pim kinase dependent regulatory mechanism for the thromboxane A2 receptor and represents a new targeting strategy that is independent of COX- 1 inhibition or direct antagonism of the thromboxane A2 receptor that whilst attenuating thrombosis does not increase bleeding

Structural, functional and mechanistic insights uncover the fundamental role of orphan connexin-62 in platelets

Connexins (Cxs) oligomerise to form hexameric hemichannels in the plasma membrane that can further dock together on adjacent cells to form gap junctions and facilitate intercellular-trafficking of molecules. In this study, we report the expression and function of an ‘orphan’ connexin, Cx62, in human and mouse (Cx57, mouse homologue) platelets. A novel mimetic peptide (62Gap27) was developed to target the second extracellular loop of Cx62 and 3D structural models predicted its interference with gap junction and hemichannel function. The ability of 62Gap27 to regulate both gap junction and hemichannel-mediated intercellular communication was observed using FRAP analysis and flow cytometry. Cx62 inhibition by 62Gap27 suppressed a range of agonist-stimulated platelet functions and impaired thrombosis and haemostasis. This was associated with elevated PKA-dependent signalling in a cyclic adenosine monophosphate-independent manner, and was not observed in Cx57 deficient mouse platelets (in which the selectivity of 62Gap27 for this connexin was also confirmed). Notably, Cx62 hemichannels were observed to function independently of Cx37 and Cx40 hemichannels. Together, our data reveal a fundamental role for a hitherto uncharacterised connexin in the regulation of the function of circulating cells

Localization and quantification of clinically relevant binding epitopes on ultra flat red blood cell ghosts

With atomic force microscopy (AFM) a sharp tip is scanned over a surface. By using an optical deection read out system, images with nanometer resolution can be obtained. Due to its ability to measure in liquid environment and by minimizing the applied force on the substrate, biological samples can be analyzed. However, the ability of AFM goes further than its imaging capability. If a ligand is attached to the AFM tip, receptor-ligand interactions can be detected and analyzed. Furthermore, an application has been developed that combines the imaging mode and the recognition detection ability of the device. This technique is called ‘Si- multaneous Topography and Recognition Imaging‘ (TREC), where not only a topographical image is recorded, but simultaneously an image that unravels the location of receptor-ligand interaction is created. Within this thesis TREC has been applied to localize specic receptors on at red blood cell ghosts. ^Erythrocyte ghosts have been known since the last century and have been used e.g. as a model to study cell membrane properties as their cell content main- ly consist of hemoglobin and they can easily be depleted of their cytosolic content. Here, a special preparation protocol was developed and optimized to produce ‘ultra-at‘ erythrocyte ghosts immobilized on glass slides, creating a perfect substrate for TREC studies. Whole ‘ultra-at‘ erythrocyte ghosts were imaged to deduce the RhD antigen quantity and distribu- tion patterns over the cell. The rst approach included scanning the erythrocyte membrane in overlapping 2x2 m windows and merging them into an complete ‘ultra-at‘ erythrocyte ghost image. Due to measurement instabilities caused by the long measuring times and oset inconsistencies caused by the high number of image location changes, another measurement approach was tested. While holding the scan speed constant the image size was increased and a whole ‘ultra-at‘ erythrocyte ghost was scanned in one TREC image (10x10 m). With the second approach we were able to gain a stable TREC signal during the whole imaging procedure. We analyzed the produced data regarding dierences in epitope densities between the rim region and the dimple region of erythrocytes. An eective and stable approach was developed to elucidate erythrocyte antigen locations and quantities. With this work an im- pression on RhD antigen distributions on erythrocytes is given. A path for further mapping of erythrocyte antigen distributions of other clinically relevant binding epitopes like weak-D and partial-D RhD antigens was being paved with this work.submitted by Sarah Stainer, BScUniversität Linz, Masterarbeit, 2018(VLID)283044

Atomic Force Microscopy Imaging in Turbid Liquids: A Promising Tool in Nanomedicine

Tracking of biological and physiological processes on the nanoscale is a central part of the growing field of nanomedicine. Although atomic force microscopy (AFM) is one of the most appropriate techniques in this area, investigations in non-transparent fluids such as human blood are not possible with conventional AFMs due to limitations caused by the optical readout. Here, we show a promising approach based on self-sensing cantilevers (SSC) as a replacement for optical readout in biological AFM imaging. Piezo-resistors, in the form of a Wheatstone bridge, are embedded into the cantilever, whereas two of them are placed at the bending edge. This enables the deflection of the cantilever to be precisely recorded by measuring the changes in resistance. Furthermore, the conventional acoustic or magnetic vibration excitation in intermittent contact mode can be replaced by a thermal excitation using a heating loop. We show further developments of existing approaches enabling stable measurements in turbid liquids. Different readout and excitation methods are compared under various environmental conditions, ranging from dry state to human blood. To demonstrate the applicability of our laser-free bio-AFM for nanomedical research, we have selected the hemostatic process of blood coagulation as well as ultra-flat red blood cells in different turbid fluids. Furthermore, the effects on noise and scanning speed of different media are compared. The technical realization is shown (1) on a conventional optical beam deflection (OBD)-based AFM, where we replaced the optical part by a new SSC nose cone, and (2) on an all-electric AFM, which we adapted for measurements in turbid liquids

Sampling, Analysis, and Properties of Primary PM-2.5: Application to Coal-Fired Utility Boilers

A dilution sampler was used to examine the effects of dilution ratio and residence time on the particulate emissions from a pilot-scale pulverized coal combustor. Measurements include the particle size distribution from 0.003 to 2.5 {micro}m, PM{sub 2.5} mass emission rate and PM2.5 composition (OC/EC, major ions, and elemental). Hot filter samples were also collected simultaneously in order to compare the dilution sampler measurement with standard stack sampling methodologies such as EPA Method 5. Measurements were made both before and after the bag-house, the particle control device used on the coal combustor. Measurements were made with three different coal types and a coal-biomass blend. The residence time and dilution ratio do not influence the PM{sub 2.5} mass emission rate, but have a significant effect on the size distribution and total number emissions. Measurements made before the bag-house showed increasing the residence time dramatically decreases the total particle number concentration, and shifts the particle mass to larger sizes. The effects of residence time can be explained quantitatively by the coagulation of the emitted particles. Measurements made after the bag-house were not affected by coagulation due to the lower concentration of particles. Nucleation of sulfuric acid vapor within the dilution was an important source of ultrafine particles. This nucleation is strongly a function of dilution ratio because of the competition between condensation and nucleation. At low dilution ratios condensation dominates and little nucleation is observed; increasing the dilution ratio promotes nucleation because of the corresponding decrease in available surface area per unit volume for condensation. No nucleation was observed after the bag house where conditions greatly favor nucleation over condensation; we suspect that the bag house removed the SO{sub 3} in the flue gas. Exhaust SO{sub 3} levels were not measured during these experiments. Dilution caused the enrichment of selenium, ammonium and sulfate in the PM{sub 2.5} emissions compared to the hot filter samples. The enrichment of selenium was independent of dilution ratio or residence time. The enrichment of ammonium and sulfate increased with increasing dilution ratio. PM{sub 2.5} emission profiles for four different fuels (two eastern bituminous coals, a western sub-bituminous coal, and coal-wood blend) were developed. These profiles compared well with profiles from similar coal sources, while showing unique characteristics due to differences in fuel composition

Targeting structural flexibility in low density lipoprotein by integrating cryo-electron microscopy and high-speed atomic force microscopy

International audienceLow-density lipoprotein (LDL) plays a crucial role in cholesterol metabolism. Responsible for cholesterol transport from the liver to the organs, LDL accumulation in the arteries is a primary cause of cardiovascular diseases, such as atherosclerosis. This work focuses on the fundamental question of the LDL molecular structure, as well as the topology and molecular motions of apolipoprotein B-100 (apo B-100), which is addressed by single-particle cryo-electron microscopy (cryo-EM) and high-speed atomic force microscopy (HS-AFM). Our results suggest a revised model of the LDL core organization with respect to the cholesterol ester (CE) arrangement. In addition, a high-density region close to the flattened poles could be identified, likely enriched in free cholesterol. The most remarkable new details are two protrusions on the LDL surface, attributed to the protein apo B-100. HS-AFM adds the dimension of time and reveals for the first time a highly dynamic direct description of LDL, where we could follow large domain fluctuations of the protrusions in real time. To tackle the inherent flexibility and heterogeneity of LDL, the cryo-EM maps are further assessed by 3D variability analysis. Our study gives a detailed explanation how to approach the intrinsic flexibility of a complex system comprising lipids and protein

Can adaptive treatment improve outcomes in family-based therapy for adolescents with anorexia nervosa? Feasibility and treatment effects of a multi-site treatment study

OBJECTIVE: Adolescents with Anorexia Nervosa (AN), treated with family-based treatment (FBT) who fail to gain 2.3 kg by the fourth week of treatment have a 40–50% lower chance of recovery than those who do. Because of the high risk of developing enduring AN, improving outcomes in this group of poor responders is essential. This study examines the feasibility and effects of a novel adaptive treatment (i.e., Intensive Parental Coaching-IPC) aimed at enhancing parental self-efficacy related to re-feeding skills in poor early responders to FBT. METHOD: 45 adolescents (12 – 18 years of age) meeting DSM TR IV criteria for AN were randomized in an unbalanced design (10 to standard FBT; 35 to the adaptive arm). Attrition, suitability, expectancy rates, weight change, and psychopathology were compared between groups. OUTCOMES: There were no differences in rates of attrition, suitability, expectancy ratings, or most clinical outcomes between randomized groups. However, the group of poor early responders that received IPC achieved full weight restoration (>95% of expected mean BMI) by EOT at similar rates as those who had responded early. CONCLUSIONS: The results of this study suggest that it is feasible to use an adaptive design to study the treatment effect of IPC for those who do not gain adequate weight by session 4 of FBT. The results also suggest that using IPC for poor early responders significantly improves weight recovery rates to levels comparable to those who respond early. A sufficiently powered study is needed to confirm these promising findings