189 research outputs found
TWO NEW SPECIES OF POACEAE FROM INDIA
Two new species of Poaceae namely, Erayrostis santapaui K. G. Bhat & C. R. Nagendran and Chrysopogon pseitdozeylanicus K. G. Bhat & C. R. Nagendran have been described from materials collected by the senior author from Coorg- and South Kanara Districts of Karnataka State, India
Decellularization reduces the immune response to aortic valve allografts in the rat
ObjectivesCryopreserved valve allografts used in congenital cardiac surgery are associated with a significant cellular and humoral immune response. This might be reduced by removal of antigenic cellular elements (decellularization). The aim of this study was to determine the immunologic effect of decellularization in a rat allograft valve model.MethodsBrown Norway and Lewis rat aortic valves were decellularized with a series of hypotonic and hypertonic buffers, protease inhibitors, gentle detergents (Triton X-100), and phosphate-buffered saline. Valves were implanted into Lewis rats in syngeneic and allogeneic combinations. Cellular (CD3 and CD8) infiltrates were assessed with morphometric analysis, and the humoral response was assessed with flow cytometry.ResultsMorphometric analysis identified a significant reduction in CD3+ cell infiltrates (cells per square millimeter of leaflet tissue) in decellularized allografts compared with that seen in nondecellularized allografts at 1 (79 ± 29 vs 3310 ± 223, P < .001), 2 (26 ± 11 vs 109 ± 20, P = .004), and 4 weeks (283 ± 122 vs 984 ± 145, P < .001). Anti-CD8 staining confirmed the majority of infiltrates were cytotoxic T cells. Flow cytometric mean channel fluorescence intensity identified a negative shift (abrogated antibody formation) for decellularized allografts compared with nondecellularized allografts at 2 (19 ± 1 vs 27 ± 3, P = .033), 4 (35 ± 2 vs 133 ± 29, P = .001), and 16 weeks (28 ± 2 vs 166 ± 54, P = .017).ConclusionsDecellularization significantly reduces the cellular and humoral immune response to allograft tissue. This could prolong the durability of valve allografts and might prevent immunologic sensitization of allograft recipients
ParaVR: A Virtual Reality Training Simulator for Paramedic Skills maintenance
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Paramedic Practice, copyright © MA Healthcare, after peer review and technical editing by the publisher. To access the final edited and published work see https://www.paramedicpractice.com/features/article/paravr-a-virtual-reality-training-simulator-for-paramedic-skills-maintenance.Background,
Virtual Reality (VR) technology is emerging as a powerful educational tool which is used in medical training and has potential benefits for paramedic practice education.
Aim
The aim of this paper is to report development of ParaVR, which utilises VR to address skills maintenance for paramedics.
Methods
Computer scientists at the University of Chester and the Welsh Ambulance Services NHS Trust (WAST) developed ParaVR in four stages: 1. Identifying requirements and specifications 2. Alpha version development, 3. Beta version development 4. Management: Development of software, further funding and commercialisation.
Results
Needle Cricothyrotomy and Needle Thoracostomy emerged as candidates for the prototype ParaVR. The Oculus Rift head mounted display (HMD) combined with Novint Falcon haptic device was used, and a virtual environment crafted using 3D modelling software, ported (a computing term meaning transfer (software) from one system or machine to another) onto Oculus Go and Google cardboard VR platform.
Conclusion
VR is an emerging educational tool with the potential to enhance paramedic skills development and maintenance. The ParaVR program is the first step in our development, testing, and scaling up of this technology
Therapeutic efficacy of TBC3711 in monocrotaline-induced pulmonary hypertension
Background: Endothelin-1 signalling plays an important role in pathogenesis of pulmonary hypertension. Although different endothelin-A receptor antagonists are developed, a novel therapeutic option to cure the disease is still needed. This study aims to investigate the therapeutic efficacy of the selective endothelin-A receptor antagonist TBC3711 in monocrotaline-induced pulmonary hypertension in rats.
Methods: Monocrotaline-injected male Sprague-Dawley rats were randomized and treated orally from day 21 to 35 either with TBC3711 (Dose: 30 mg/kg body weight/day) or placebo. Echocardiographic measurements of different hemodynamic and right-heart hypertrophy parameters were performed. After day 35, rats were sacrificed for invasive hemodynamic and right-heart hypertrophy measurements. Additionally, histologic assessment of pulmonary vascular and right-heart remodelling was performed.
Results: The novel endothelin-A receptor antagonist TBC3711 significantly attenuated monocrotaline-induced pulmonary hypertension, as evident from improved hemodynamics and right-heart hypertrophy in comparison with placebo group. In addition, muscularization and medial wall thickness of distal pulmonary vessels were ameliorated. The histologic evaluation of the right ventricle showed a significant reduction in fibrosis and cardiomyocyte size, suggesting an improvement in right-heart remodelling.
Conclusion: The results of this study suggest that the selective endothelin-A receptor antagonist TBC3711 demonstrates therapeutic benefit in rats with established pulmonary hypertension, thus representing a useful therapeutic approach for treatment of pulmonary hypertension
Understanding plant cell-wall remodelling during the symbiotic interaction between Tuber melanosporum and Corylus avellana using a carbohydrate microarray
Concerted Regulation of cGMP and cAMP Phosphodiesterases in Early Cardiac Hypertrophy Induced by Angiotensin II
Left ventricular hypertrophy leads to heart failure and represents a high risk leading to premature death. Cyclic nucleotides (cAMP and cGMP) play a major role in heart contractility and cyclic nucleotide phosphodiesterases (PDEs) are involved in different stages of advanced cardiac diseases. We have investigated their contributions in the very initial stages of left ventricular hypertrophy development. Wistar male rats were treated over two weeks by chronic infusion of angiotensin II using osmotic mini-pumps. Left cardiac ventricles were used as total homogenates for analysis. PDE1 to PDE5 specific activities and protein and mRNA expressions were explored
The babel of drugs: On the consequences of evidential pluralism in pharmaceutical regulation and regulatory data journeys
This is the final version. Available on open access from Springer via the DOI in this recordThroughout the last century, pharmaceutical regulators all over the world have used various methods to test medical treatments. From 1962 until 2016, the Randomized Clinical Trial (RCT) was the reference test for most regulatory agencies. Today, the standards are about to change, and in this chapter we draw on the idea of the data journey to illuminate the trade-offs involved. The 21st Century Cures Act (21CCA) allows for the use of Electronic Health Records (EHRs) for the assessment of different treatment indications for already approved drugs. This might arguably shorten the testing period, bringing treatments to patients faster. Yet, EHR are not generated for testing purposes and no amount of standardization and curation can fully make up for their potential flaws as evidence of safety and efficacy. The more noise in the data, the more mistakes regulators are likely to make in granting market access to new drugs. In this paper we will discuss the different dimensions of this journey: the different sources and levels of curation involved, the speed at which they can travel, and the level of risk of regulatory error involved as compared with the RCT standard. We are going to defend that what counts as evidence, at the end of the journey, depends on the risk definition and threshold regulators work with.European Research Council (ERC)Engineering and Physical Sciences Research Council (EPSRC
When simulated environments make the difference: the effectiveness of different types of training of car service procedures
An empirical analysis was performed to compare the effectiveness of different approaches to training a set of procedural skills to a sample of novice trainees. Sixty-five participants were randomly assigned to one of the following three training groups: (1) learning-by-doing in a 3D desktop virtual environment, (2) learning-by-observing a video (show-and-tell) explanation of the procedures, and (3) trial-and-error. In each group, participants were trained on two car service procedures. Participants were recalled to perform a procedure either 2 or 4 weeks after the training. The results showed that: (1) participants trained through the virtual approach of learning-by-doing performed both procedures significantly better (i.e. p < .05 in terms of errors and time) than people of non-virtual groups, (2) the virtual training group, after a period of non-use, were more effective than non-virtual training (i.e. p < .05) in their ability to recover their skills, (3) after a (simulated) long period from the training—i.e. up to 12 weeks—people who experienced 3D environments consistently performed better than people who received other kinds of training. The results also suggested that independently from the training group, trainees’ visuospatial abilities were a predictor of performance, at least for the complex service procedure, adj R2 = .460, and that post-training performances of people trained through virtual learning-by-doing are not affected by learning styles. Finally, a strong relationship (p < .001, R2 = .441) was identified between usability and trust in the use of the virtual training tool—i.e. the more the system was perceived as usable, the more it was perceived as trustable to acquire the competences
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