Echocardiographic diagnosis of permanent pacemaker lead malposition in the left ventricle: A case study

Inadvertent endocardial lead malposition is recognized as a rare incident which is usually underreported and if recognized during implantation can be easily corrected. This phenomenon is caused by the ventricular lead unintentionally crossing a pre-existing patent foremen ovale, septal defects (atrial or ventricular) or directly from the aorta via an accidental subclavian puncture resulting in the lead implanting into the left ventricle. While this is a rare occurrence we report, the incidental finding of pacemaker lead malposition during a routine follow-up transthoracic echocardiogram and the benefits of three-dimensional transesophageal echocardiography in this patient prior to lead extraction.     

Bioprinted gelatin hydrogel platform promotes smooth muscle cell contractile phenotype maintenance

Three dimensional (3D) bioprinting has been proposed as a method for fabricating tissue engineered small diameter vascular prostheses. This technique not only involves constructing the structural features to obtain a desired pattern but the morphology of the pattern may also be used to influence the behavior of seeded cells. Herein, we 3D bioprinted a gelatin hydrogel microchannel construct to promote and preserve the contractile phenotype of vascular smooth muscle cells (vSMCs), which is crucial for vasoresponsiveness. The microchanneled surface of a gelatin hydrogel facilitated vSMC attachment and an elongated alignment along the microchannel direction. The cells displayed distinct F-actin anisotropy in the direction of the channel. The vSMC contractile phenotype was confirmed by the positive detection of contractile marker gene proteins (α-smooth muscle actin (α-SMA) and smooth muscle-myosin heavy chain (SM-MHC)). Having demonstrated the effectiveness of the hydrogel channels bioprinted on a film, the bioprinting was applied radially to the surface of a 3D tubular construct by integrating a rotating mandrel into the 3D bioprinter. The hydrogel microchannels printed on the 3D tubular vascular construct also orientated the vSMCs and strongly promoted the contractile phenotype. Together, our study demonstrated that microchannels bioprinted using a transglutaminase crosslinked gelatin hydrogel, could successfully promote and preserve vSMC contractile phenotype. Furthermore, the hydrogel bioink could be retained on the surface of a rotating polymer tube to print radial cell guiding channels onto a vascular graft construct.     

Services for children with developmental co-ordination disorder: an evaluation against best practice principles

Purpose: The National Health Service in Scotland published a best practice framework to support occupational therapists and physiotherapists to deliver effective services for children with developmental co-ordination disorder (DCD); however, adherence is variable. To highlight areas for development, this study compared the care pathway within a paediatric DCD service against the NHS Scotland framework. Methods: A partnership of researchers and clinicians based in the United Kingdom conducted a qualitative study with 37 participants (N?=?13 interview participants, N?=?24 workshop participants). In-depth interviews and/or workshops were used to map the DCD service against the NHS framework. Identified gaps were aligned with four key stages of the care pathway. Qualitative analysis software was used to analyse the data. Results: Core principles to guide future development were identified for each phase of the pathway. These core principles related to the NHS framework and focused on issues such as involving the family, defining clear pathways and enhancing children’s participation. Participants identified potential strategies for service improvement such as developing community-based interventions and information provision. Conclusion: Challenges when providing services for children with DCD include confusing service pathways and poor partnership working. It is, therefore, important that clinicians utilise collaborative working strategies that support children’s participation.

• Implications for Rehabilitation

• There are numerous challenges related to the implementation of best practice principles into the provision of therapy services for children with developmental coordination disorder (DCD).

• It is important that AHPs seek ways of engaging parents and educational professionals at all stages of the care pathway in order to ensure optimum service provision for the child.

• Addressing participation is an important aspect and community-based strategies may be particularly beneficial, both as a preventative activity and as an intervention approach.

     

Risk-Taking in Disorders of Natural and Drug Rewards: Neural Correlates and Effects of Probability,Valence, and Magnitude

Pathological behaviors toward drugs and food rewards have underlying commonalities. Risk-taking has a fourfold pattern varying as a function of probability and valence leading to the nonlinearity of probability weighting with overweighting of small probabilities and underweighting of large probabilities. Here we assess these influences on risk-taking in patients with pathological behaviors toward drug and food rewards and examine structural neural correlates of nonlinearity of probability weighting in healthy volunteers. In the anticipation of rewards, subjects with binge eating disorder show greater risk-taking, similar to substance-use disorders. Methamphetamine-dependent subjects had greater nonlinearity of probability weighting along with impaired subjective discrimination of probability and reward magnitude. Ex-smokers also had lower risk-taking to rewards compared with non-smokers. In the anticipation of losses, obesity without binge eating had a similar pattern to other substance-use disorders. Obese subjects with binge eating also have impaired discrimination of subjective value similar to that of the methamphetamine-dependent subjects. Nonlinearity of probability weighting was associated with lower gray matter volume in dorsolateral and ventromedial prefrontal cortex and orbitofrontal cortex in healthy volunteers. Our findings support a distinct subtype of binge eating disorder in obesity with similarities in risk-taking in the reward domain to substance use disorders. The results dovetail with the current approach of defining mechanistically based dimensional approaches rather than categorical approaches to psychiatric disorders. The relationship to risk probability and valence may underlie the propensity toward pathological behaviors toward different types of rewards.     

An interchangeable role for kainate and metabotropic glutamate receptors in the induction of rat hippocampal mossy fiber long‐term potentiation in vivo

The roles of both kainate receptors (KARs) and metabotropic glutamate receptors (mGluRs) in mossy fiber long‐term potentiation (MF‐LTP) have been extensively studied in hippocampal brain slices, but the findings are controversial. In this study, we have addressed the roles of both mGluRs and KARs in MF‐LTP in anesthetized rats. We found that MF‐LTP could be induced in the presence of either GluK1‐selective KAR antagonists or group I mGluR antagonists. However, LTP was inhibited when the group I mGluRs and the GluK1‐KARs were simultaneously inhibited. Either mGlu1 or mGlu5 receptor activation is sufficient to induce this form of LTP as selective inhibition of either subtype alone, together with the inhibition of KARs, did not inhibit MF‐LTP. These data suggest that mGlu1 receptors, mGlu5 receptors, and GluK1‐KARs are all engaged during high‐frequency stimulation, and that the activation of any one of these receptors alone is sufficient for the induction of MF‐LTP in vivo. © 2015 The Authors Hippocampus Published by Wiley Periodicals, Inc.