Presynaptic efficacy directs normalization of synaptic strength in layer 2/3 rat neocortex after paired activity

Paired neuronal activity is known to induce changes in synaptic strength that result in the synapse in question having different properties to unmodified synapses. Here we show that in layer 2/3 excitatory connections in young adult rat cortex paired activity acts to normalize the strength and quantal parameters of connections. Paired action potential firing produces long-term potentiation in only a third of connections, whereas a third remain with their amplitude unchanged and a third exhibit long-term depression. Furthermore, the direction of plasticity can be predicted by the initial strength of the connection: weak connections potentiate and strong connections depress. A quantal analysis reveals that changes in synaptic efficacy were predominantly presynaptic in locus and that the key determinant of the direction and magnitude of synaptic modification was the initial release probability (P(r)) of the synapse, which correlated inversely with change in P(r) after pairing. Furthermore, distal synapses also exhibited larger potentiations including postsynaptic increases in efficacy, whereas more proximal inputs did not. This may represent a means by which distal synapses preferentially increase their efficacy to achieve equal weighting at the soma. Paired activity thus acts to normalize synaptic strength, by both pre- and postsynaptic mechanisms.     

Lower limb immobilization is associated with increased corticospinal excitability

Temporary immobilization of the leg serves as a useful model for the brain’s adaptive responses to casting, long-term confinement to bed rest and possibly to trauma. As part of a larger program using TMS to investigate changes associated with bed rest, we sought to determine whether casting of the leg causes brain excitability changes measurable with TMS, and the time course of resolution of these changes. In this study, eight adults wore a full leg cast for 10 days. TMS measures of motor cortex excitability were gathered before the cast was placed, and then immediately after cast removal, and 24 and 48 h later. A control group did not wear a cast and underwent the same TMS sessions. Significant excitability changes occurred and peaked at 24 h post cast removal in the TMS experimental group but not the non-casted group.     

Digital autoradiography using room temperature CCD and CMOS imaging technology

CCD (charged coupled device) and CMOS imaging technologies can be applied to thin tissue autoradiography as potential imaging alternatives to using conventional film. In this work, we compare two particular devices: a CCD operating in slow scan mode and a CMOS-based active pixel sensor, operating at near video rates. Both imaging sensors have been operated at room temperature using direct irradiation with images produced from calibrated microscales and radiolabelled tissue samples. We also compare these digital image sensor technologies with the use of conventional film. We show comparative results obtained with (14)C calibrated microscales and (35)S radiolabelled tissue sections. We also present the first results of (3)H images produced under direct irradiation of a CCD sensor operating at room temperature. Compared to film, silicon-based imaging technologies exhibit enhanced sensitivity, dynamic range and linearity.     

Subjektive Qualitätskonzepte im Vergleich zu objektiven Qualitätskriterien

Background

The need for quality management in prevention and health promotion continues to grow. The role of the participants’ and course instructors’ views on quality in prevention and health promotion has been insufficiently considered. The aim of the present study was to examine the participants’ and course instructors’ views on quality in movement-related prevention and health promotion.

Methods

Four participants and four course instructors were questioned using semistructured interviews. The data were analyzed according to the structured content analysis according to Kuckartz.

Results

The views on quality of participants and course instructors were comparable. Within the participants’ and course instructors’ views on quality in movement-related prevention and health promotion the “individual relationship between therapist and patient”, “personal atmosphere”, and “class structure” were identified as important quality dimensions, while proof of effectiveness seemed to be less important. Moreover, the understanding of proof of effectiveness turned out to be inconsistent.

Conclusions

Compared to the prevention guideline of the German statutory health insurers, participants’ and course instructors’ views on quality point out the importance of process quality. In contrast, proof of effectiveness and the qualification of the course instructor play a minor role in subjective quality concepts.

     

Einführung in die Vergangenheit,Gegenwart und Zukunft von Serious Games (for Health)

Background

(Serious) Games have been used for several educational and health-related interventions in health promotion and prevention. The use of games for serious purposes is strategy that dates back to the beginning of humankind.

Objectives

The following article will outline the evolutionary lines of Serious Games, starting with the first traces of games in human history up to the present. In-depth consideration of factors influencing the development of Serious Games in the past and present outline possible future developments and may lead to a better understanding of today’s developments.

Materials and methods

The present work is a narrative review and outlines the most important developments of games. The development of Serious Games for Health will be considered in more detail. The various influencing factors from the entertainment and military sectors are outlined as well as new technologies that change the use of games for serious purposes.

Results

The development of Serious Games in the history of humankind is shown in a timeline. Games with a serious intention have been part of the culture since the beginning of humanity. Serious Games is not a new technology trigger, but has always been closely linked to learning. Various factors influencing the development of Serious Games have led to a very diverse, interprofessional and interdisciplinary field of research and application.

Conclusions

Serious Games (for Health) and playful applications like gamification offer great potential for work in prevention, health promotion, medicine and health education. Due to the widespread use of the medium of play as an integral aspect of everyday life and culture, the achievement of hard-to-reach groups through this type of medium is very well possible. Aspects such as immersion, flow, storytelling and high interactivity and direct feedback make games an effective intervention strategy.

     

Higher serotonin transporter availability in early‐onset obsessive–compulsive disorder patients undergoing escitalopram treatment: A [11C]DASB PET study

Objective

Early‐onset obsessive–compulsive disorder (EOCD) and late‐onset obsessive–compulsive disorder (LOCD) are distinct subtypes of obsessive–compulsive disorder (OCD). OCD patients are treated with serotonin reuptake inhibitors, but the difference in serotonin transporter (SERT) availability between medicated EOCD and LOCD is unexplored yet.

Methods

Six EOCD and 6 LOCD patients were enrolled. They underwent serial [¹¹C]DASB positron emission tomography scans during maintenance therapy with escitalopram, and their plasma concentration of escitalopram was measured simultaneously with the scan. Then, the drug‐free binding potential of SERT was calculated by pharmacokinetic–pharmacodynamic modelling.

Results

In comparison with LOCD patients, SERT availability was significantly higher in the putamen of EOCD patients (U = 4, p = .026), but not in the caudate nucleus (U = 14, p = .589), thalamus (U = 16, p = .818), and dorsal raphe nucleus (U = 7, p = .093). Binding potential of putamen showed a negative correlation (r = ?.580, p = .048) with age of onset of the disease, but not with the Yale–Brown Obsessive Compulsive Scale scores.

Conclusions

These findings indicate that the earlier the age of onset of OCD, the less serotonergic pathology there is and that this difference remains even after long‐term serotonin reuptake inhibitor treatment. Clinically, it might suggest that nonserotonergic treatments would be a better option for EOCD patients.     

The grades that clinical teachers give students modifies the grades they receive

Prior studies have shown a correlation between the grades students receive and how they rate their teacher in the classroom. In this study, the authors probe this association on clinical rotations and explore potential mechanisms. All In-Training Evaluation Reports (ITERs) for students on mandatory clerkship rotations from April 1, 2013 to January 31, 2015 were matched with the corresponding student’s rating of their teacher (SRT). The date and time that ITERs and SRTs were submitted was used to divide SRTs into those submitted before versus after the corresponding ITER was submitted. Multilevel, mixed effects linear regression was used to examine the association between SRT, ITER rating, and whether the ITER was submitted before or after SRT. Of 2373 paired evaluations, 1098 (46.3%) SRT were submitted before the teacher had submitted the ITER. There was a significant interaction between explanatory variables: when ITER ratings had not yet been submitted, the regression coefficient for this association was 0.25 (95% confidence interval [0.17, 0.33], p < 0.001), whereas the regression coefficient was significantly higher when ITER ratings were submitted prior to SRT (0.40 [0.31, 0.49], p < 0.001). Finding an association between SRT and ITER when students do not know their ITER ratings suggests that SRTs can capture attributes of effective teaching, but the effect modification when students have access to their ITER rating supports grade satisfaction bias. Further studies are needed to explain the mechanism of grade satisfaction and to identify other biases that may impact the validity of SRT.