Reform of the Coal Sector in an Open Economy: The Case of China

Cheap, abundant and easy to transport and store, coal has been produced and consumed to meet people's energy needs. The last decade's growth in global coal use has been driven mainly by developing economies like China, whose phenomenal economic growth has been powered by coal-fired electricity and promoted by the export of manufactured goods. A recent reform focus in China's coal sector is on coal taxation. The paper develops a game-theoretic model tailored to the context of China where coal taxation reform takes place against the background of privatisation of coal firms and an open economy. It finds that the adoption of special coal taxes is optimal for social welfare under most circumstances, but may induce coal firms to commit opportunistic behaviour in the process of privatisation. The paper also cautions about potential resistance to the reform from consumers, coal firms and government officials

Application of Molecular Dynamics methods to the study of biological systems

La aplicación de métodos de dinámica molecular (MD) para el estudio de sistemas biológicos. Esta tesis se centra en la aplicación tanto de dinámica molecular clásica como perturbación de energía libre (FEP) para estudiar sistemas biológicos tales como los receptores acoplados a proteínas G y los inhibidores de BACE1. La tesis se divide en 5 secciones, en primer lugar, una introducción donde se explica la evolución de la metodología de MD, en segundo lugar, una sección sobre métodos utilizados en esta tesis, la tercera sección se centra en el uso de simulaciones de MD para estudiar dos aspectos diferentes de los GPCR, oligomerización del tetrámero formado por receptores de adenosina y el mecanismo de activación por ligandos alostéricos dirigidos al receptor metabotrópico de glutamato 2. La cuarta sección se centra en la aplicación de FEP con el objetivo de diseñar nuevos inhibidores de BACE1 y poner en práctica esta metodología en un proyecto de desarrollo de fármacos realizado en colaboración con Janssen Pharmaceutica. La última sección resume las conclusiones alcanzadas. En general, se demuestra que los métodos de Dinámica Molecular, puede ser de gran valor para comprender los escenarios descritos a nivel molecular, y, en particular, las interacciones y los procesos dinámicos que se producen. Esto a su vez ayudará a la comprensión más detallada de la biología básica y el diseño de fármacos. El trabajo justifica aplicaciones futuras en estas áreas y continua la exploración de forma detallada de la influencia que los métodos MD y FEP pueden alcanzar.Application of Molecular Dynamics (MD) methods to the study of biological systems. This thesis is focused on the application of both classical MD and free energy perturbation (FEP) to study biological systems such as G protein-coupled receptors and BACE1 inhibitors. The thesis is divided into 5 sections, firstly an introduction where a timeline and evolution of MD methodology is explained, secondly a second section on Methods, the third section focuses on the use of MD simulation to study two different aspects of GPCRs, oligomerization of the tetramer formed by Adenosine receptors and the mechanism of activation by allosteric ligands targeting the metabotropic glutamate 2 receptor. The fourth section is focused on the application of FEP with the aim of designing new BACE1 inhibitors and to implement this methodology into a real drug discovery project performed in collaboration with Janssen Pharmaceutica. The final section summarizes the conclusions reached. Overall, it is shown that state of the art MD simulations, and hence modern computational methodology, can be of value to understand the described scenarios at the molecular level, and in particular the interactions and dynamic processes which occur. This in turn will help with more detailed understanding of basic biology and drug design. The work justifies future applications in these areas and continued deeper exploration of the limits of the impact which MD and FEP methods can reach

microRNA Expression and Its Association With Disability and Brain Atrophy in Multiple Sclerosis Patients Treated With Glatiramer Acetate.

Background: MicroRNAs are small non-coding RNA that regulate gene expression at a post-transcriptional level affecting several cellular processes including inflammation, neurodegeneration and remyelination. Different patterns of miRNAs expression have been demonstrated in multiple sclerosis compared to controls, as well as in different courses of the disease. For these reason they have been postulated as promising biomarkers candidates in multiple sclerosis. Objective: To correlate serum microRNAs profile expression with disability, cognitive functioning and brain volume in patients with remitting-relapsing multiple sclerosis. Methods: Cross-sectional study in relapsing-remitting multiple sclerosis patients treated with glatiramer acetate. Disability was measured with Expanded Disability Status Scale (EDSS) and cognitive function was studied with Symbol Digit Modalities Test (SDMT). Brain volume was analyzed with automatic software NeuroQuant® . Results: We found an association between miR.146a.5p (rs:0.434, p=0.03) and miR.9.5p (rs:0.516, p=0.028) with EDSS; and miR-146a.5p (rs:-0.476, p=0.016) and miR-126.3p (rs:-0.528, p=0.007) with SDMT. Regarding to the brain volume, miR.9.5p correlated with thalamus (rs:-0.545, p=0.036); miR.200c.3p with pallidum (rs:-0.68, p=0.002) and cerebellum (rs:-0.472, p=0.048); miR-138.5p with amygdala (rs:0.73, p=0.016) and pallidum (rs:0.64, p=0.048); and miR-223.3p with caudate (rs:0.46, p=0.04). Conclusions: These data support the hypothesis of microRNA as potential biomarkers in this disease. More studies are needed to validate these results and to better understand the role of microRNAs in the pathogenesis, monitoring and therapeutic response of multiple sclerosis.post-print1410 K

Selective inhibitors of the PSEN1–gamma-secretase complex

Clinical development of γ-secretases, a family of intramembrane cleaving proteases, as therapeutic targets for a variety of disorders including cancer and Alzheimer’s disease was aborted because of serious mechanism-based side effects in the phase III trials of unselective inhibitors. Selective inhibition of specific γ-secretase complexes, containing either PSEN1 or PSEN2 as the catalytic subunit and APH1A or APH1B as supporting subunits, does provide a feasible therapeutic window in preclinical models of these disorders. We explore here the pharmacophoric features required for PSEN1 versus PSEN2 selective inhibition. We synthesized a series of brain penetrant 2-azabicyclo[2,2,2]octane sulfonamides and identified a compound with low nanomolar potency and high selectivity (>250-fold) toward the PSEN1–APH1B subcomplex versus PSEN2 subcomplexes. We used modeling and site-directed mutagenesis to identify critical amino acids along the entry part of this inhibitor into the catalytic site of PSEN1. Specific targeting one of the different γ-secretase complexes might provide safer drugs in the future

Selective inhibitors of the PSEN1-gamma-secretase complex

Clinical development of Y-secretases, a family of intramembrane cleaving proteases, as therapeutic targets for a variety of disorders including cancer and Alzheimer’s disease was aborted because of serious mechanism-based side effects in the phase III trials of unselective inhibitors. Selective inhibition of specific Y-secretase complexes, containing either PSEN1 or PSEN2 as the catalytic subunit and APH1A or APH1B as supporting subunits, does provide a feasible therapeutic window in preclinical models of these disorders. We explore here the pharmacophoric features required for PSEN1 versus PSEN2 selective inhibition. We synthesized a series of brain penetrant 2-azabicyclo[2,2,2]octane sulfonamides and identified a compound with low nanomolar potency and high selectivity (>250-fold) toward the PSEN1–APH1B subcomplex versus PSEN2 subcomplexes. We used modeling and site-directed mutagenesis to identify critical amino acids along the entry part of this inhibitor into the catalytic site of PSEN1. Specific targeting one of the different Y-secretase complexes might provide safer drugs in the future.The work was supported by an AIO-project (no. HBC.2016.0884). This project received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme (grant agreement no. ERC-834682 CELLPHASE_AD). This work was supported by the Flanders Institute for Biotechnology (VIB vzw), a Methusalem grant from KU Leuven and the Flemish Government, the Fonds voor Wetenschappelijk Onderzoek, KU Leuven, The Queen Elisabeth Medical Foundation for Neurosciences, the Opening the Future campaign of the Leuven Universitair Fonds, the Belgian Alzheimer Research Foundation (SAO-FRA), and the Alzheimer’s Association USA.Peer ReviewedPostprint (published version

Best practices for constructing, preparing, and evaluating protein-ligand binding affinity benchmarks

Free energy calculations are rapidly becoming indispensable in structure-enabled drug discovery programs. As new methods, force fields, and implementations are developed, assessing their expected accuracy on real-world systems (benchmarking) becomes critical to provide users with an assessment of the accuracy expected when these methods are applied within their domain of applicability, and developers with a way to assess the expected impact of new methodologies. These assessments require construction of a benchmark - a set of well-prepared, high quality systems with corresponding experimental measurements designed to ensure the resulting calculations provide a realistic assessment of expected performance when these methods are deployed within their domains of applicability. To date, the community has not yet adopted a common standardized benchmark, and existing benchmark reports suffer from a myriad of issues, including poor data quality, limited statistical power, and statistically deficient analyses, all of which can conspire to produce benchmarks that are poorly predictive of real-world performance. Here, we address these issues by presenting guidelines for (1) curating experimental data to develop meaningful benchmark sets, (2) preparing benchmark inputs according to best practices to facilitate widespread adoption, and (3) analysis of the resulting predictions to enable statistically meaningful comparisons among methods and force fields

Quaternary structure of a G-protein coupled receptor heterotetramer in complex with Gi and Gs

Background: G-protein-coupled receptors (GPCRs), in the form of monomers or homodimers that bind heterotrimeric G proteins, are fundamental in the transfer of extracellular stimuli to intracellular signaling pathways. Different GPCRs may also interact to form heteromers that are novel signaling units. Despite the exponential growth in the number of solved GPCR crystal structures, the structural properties of heteromers remain unknown. Results: We used single-particle tracking experiments in cells expressing functional adenosine A1-A2A receptors fused to fluorescent proteins to show the loss of Brownian movement of the A1 receptor in the presence of the A2A receptor, and a preponderance of cell surface 2:2 receptor heteromers (dimer of dimers). Using computer modeling, aided by bioluminescence resonance energy transfer assays to monitor receptor homomerization and heteromerization and G-protein coupling, we predict the interacting interfaces and propose a quaternary structure of the GPCR tetramer in complex with two G proteins. Conclusions: The combination of results points to a molecular architecture formed by a rhombus-shaped heterotetramer, which is bound to two different interacting heterotrimeric G proteins (Gi and Gs). These novel results constitute an important advance in understanding the molecular intricacies involved in GPCR function

Contributions of myofascial pain in diagnosis and treatment of shoulder pain. A randomized control trial

<p>Abstract</p> <p>Background</p> <p>Rotator cuff tendinopathy and subacromial impingement syndrome present complex patomechanical situations, frequent difficulties in clinical diagnosis and lack of effectiveness in treatment. Based on clinical experience, we have therefore considered the existence of another pathological entity as the possible origin of pain and dysfunction. The hypothesis of this study is to relate subacromial impingement syndrome (SIS) with myofascial pain syndrome (MPS), since myofascial trigger points (MTrPs) cause pain, functional limitation, lack of coordination and alterations in quality of movement, even prior to a tendinopathy. MTrPs can coexist with any degenerative subacromial condition. If they are not taken into consideration, they could perpetuate and aggravate the problem, hindering diagnosis and making the applied treatments ineffective.</p> <p>The aims and methods of this study are related with providing evidence of the relationship that may exist between this condition and MPS in the diagnosis and treatment of rotator cuff tendonitis and/or SIS.</p> <p>Method/design</p> <p>A descriptive transversal study will be made to find the correlation between the diagnosis of SIS and rotator cuff tendonitis, positive provocation test responses, the existence of active MTrPs and the results obtained with ultrasonography (US) and Magnetic Renonance Imaging (MRI). A randomized double blinded clinical trial will be carried out in experimental conditions: A Protocolized treatment based on active and passive joint repositioning, stabilization exercises, stretching of the periarticular shoulder muscles and postural reeducation. B. The previously described protocolized treatment, with the addition of dry needling applied to active MTrPs with the purpose of isolating the efficacy of dry needling in treatment.</p> <p>Discussion</p> <p>This study aims to provide a new vision of shoulder pain, from the perspective of MPS. This syndrome can, by itself, account for shoulder pain and dysfunction, although it can coexist with real conditions involving the tendons.</p> <p>Trail Registration</p> <p>ISRCTN Number: 30907460</p

Incidence and clearance of anal high-risk human papillomavirus in HIV-positive men who have sex with men: Estimates and risk factors

Background: To estimate incidence and clearance of high-risk human papillomavirus (HR-HPV), and their risk factors, in men who have sex with men (MSM) recently infected by HIV in Spain; 2007-2013. Methods: Multicenter cohort. HR-HPV infection was determined and genotyped with linear array. Two-state Markov models and Poisson regression were used. Results: We analysed 1570 HR-HPV measurements of 612 MSM over 13 608 person-months (p-m) of follow-up. Median (mean) number of measurements was 2 (2.6), median time interval between measurements was 1.1 years (interquartile range: 0.89-1.4). Incidence ranged from 9.0 [95% confidence interval (CI) 6.8-11.8] per 1000 p-m for HPV59 to 15.9 (11.7-21.8) per 1000 p-m for HPV51. HPV16 and HPV18 had slightly above average incidence: 11.9/1000 p-m and 12.8/1000 p-m. HPV16 showed the lowest clearance for both 'prevalent positive' (15.7/1000 p-m; 95% CI 12.0-20.5) and 'incident positive' infections (22.1/1000 p-m; 95% CI 11.8-41.1). More sexual partners increased HR-HPV incidence, although it was not statistically significant. Age had a strong effect on clearance (P-value < 0.001) due to the elevated rate in MSM under age 25; the effect of HIV-RNA viral load was more gradual, with clearance rate decreasing at higher HIV-RNA viral load (P-value 0.008). Conclusion: No large variation in incidence by HR-HPV type was seen. The most common incident types were HPV51, HPV52, HPV31, HPV18 and HPV16. No major variation in clearance by type was observed, with the exception of HPV16 which had the highest persistence and potentially, the strongest oncogenic capacity. Those aged below 25 or with low HIV-RNA- viral load had the highest clearanceThis work was supported by grants from the Fondo de Investigacio´n Sanitaria [PI06/0372, PS09/2181], Red de Investigacio´n en SIDA (RIS) [RD06/006/0026 and RD12/0017/0018 to C.G.] and CIBERESP [group 54A-CB06/02/1009