314 research outputs found
Unraveling the Interplay between Quantum Transport and Geometrical Conformations in Monocyclic Hydrocarbons Molecular Junctions
In the field of molecular electronics, particularly in quantum transport
studies, the orientation of molecules plays a crucial role. This orientation,
with respect to the electrodes, can be defined through the cavity of
ring-shaped monocyclic hydrocarbon molecules. In this manuscript, we unveil the
geometrical conformation of these molecules when they are trapped between two
atomically sharp electrodes through a combination of dynamic simulations,
electronic transport calculations based on density functional theory, and break
junction experiments under room conditions. Moreover, we present a novel
criterion for determining the molecular orientation of benzene, toluene,
(aromatic) and cyclohexane (aliphatic) solvents. Our findings for the
identification of the molecular orientations on gold metal nanocontacts and
their associated transport properties, can improve the understanding of
molecular electronics using more complex cyclic hydrocarbons.Comment: 8 pages,9 figures, suplemental material include
Functional Evaluation of the Visual Pathway in Patients with Multiple Sclerosis Using a Multifunction Stimulator Monitor
Objectives. To assess the capability of the vision monitor unit Monpack One of detecting visual function alterations in patients with multiple sclerosis (MS) and to evaluate the correlation between structural retinal parameters and functional measurements obtained with this device. Methods. Forty-eight patients with MS and 46 healthy controls were included in a cross-sectional study. All participants underwent a complete functional evaluation of the visual pathway, which included low-contrast visual acuity (LCVA), contrast sensitivity vision (CSV), automated perimetry, multifocal visual evoked potentials (mfVEPs), and pattern electroretinogram (ERG). All tests were performed using the vision monitor unit Monpack One (Metrovision, France), a multifunction stimulator device. Retinal structural measurements were obtained in all subjects using Triton swept source optical coherence tomography (Topcon, Japan). Results. Patients with MS presented reduced low-contrast VA (p<0.001) and reduced CSV at medium (p=0.001, p=0.013) and low (p=0.001, p=0.002) spatial frequencies. All visual field parameters were found to be altered in MS patients compared with controls (<= 0.001). Patients with MS presented lower amplitude of the P100 waveform of the mfVEP in areas corresponding to central (p<0.001), inferonasal (p=0.001), and inferotemporal (p=0.003) retina. The pattern ERG did not show significant differences. Significant correlations were observed between structural retinal measurements and functional parameters, especially between the inner macular areas and measurements corresponding to contrast sensitivity and perimetry indexes. Conclusions. Patients with MS present visual dysfunction detectable with the vision monitor unit Monpack One. This device may be a fast and useful tool to provide a full evaluation of axonal damage in patients with multiple sclerosis
Retinal and Optic Nerve Degeneration in Patients with Multiple Sclerosis Followed up for 5 Years
Purpose: To quantify retinal nerve fiber layer (RNFL) changes in patients with multiple sclerosis (MS) and healthy controls with a 5-year follow-up and to analyze correlations between disability progression and RNFL degeneration.
Design: Observational and longitudinal study.
Participants: One hundred patients with relapsing-remitting MS and 50 healthy controls.
Methods: All participants underwent a complete ophthalmic and electrophysiologic exploration and were re-evaluated annually for 5 years.
Main Outcome Measures: Visual acuity (Snellen chart), color vision (Ishihara pseudoisochromatic plates), visual field examination, optical coherence tomography (OCT), scanning laser polarimetry (SLP), and visual evoked potentials. Expanded Disability Status Scale (EDSS) scores, disease duration, treatments, prior optic neuritis episodes, and quality of life (QOL; based on the 54-item Multiple Sclerosis Quality of Life Scale score).
Results: Optical coherence tomography (OCT) revealed changes in all RNFL thicknesses in both groups. In the MS group, changes were detected in average thickness and in the mean deviation using the GDx-VCC nerve fiber analyzer (Laser Diagnostic Technologies, San Diego, CA) and in the P100 latency of visual evoked potentials; no changes were detected in visual acuity, color vision, or visual fields. Optical coherence tomography showed greater differences in the inferior and temporal RNFL thicknesses in both groups. In MS patients only, OCT revealed a moderate correlation between the increase in EDSS and temporal and superior RNFL thinning. Temporal RNFL thinning based on OCT results was correlated moderately with decreased QOL.
Conclusions: Multiple sclerosis patients exhibit a progressive axonal loss in the optic nerve fiber layer. Retinal nerve fiber layer thinning based on OCT results is a useful marker for assessing MS progression and correlates with increased disability and reduced QOL
Tasa de presentación de celo y concepción en cabras Saanen sincronizadas con acetato de medroxiprogesterona (MAP) en dos épocas del año
The study aimed to evaluate the rates of visual oestrous and conception in Saanen goats subjected to oestrus synchronization at two seasons of the year. Hormonal synchronization was done using an intravaginal sponge impregnated with medroxyprogesterone acetate (MAP), for 11 days. In addition, 48 hours before sponge removal, 300 IU equine chorionic gonadotropin (eCG) and 125 µg cloprostenol were administered. The goats that showed heat were mounted by fertile males. The pregnancy diagnosis was done 60 days after the service by transrectal ultrasound. The rate of presentation of heat was 86.7 and 96.7% for the anoestrous season (January-February) and the cyclicity season (March-April), respectively, without significant difference between periods. The conception rate was 88.5 and 62.1% for the periods January-February and March-April, respectively (p<0.05). It is concluded that the use of MAP impregnated intravaginal sponges for the synchronization of oestrus in Saanen goats is effective, regardless of the time of year.El estudio tuvo como objetivo evaluar las tasas de presentación de celo y concepción en cabras Saanen con sincronización del estro en dos épocas del año. La sincronización hormonal se hizo mediante una esponja intravaginal impregnada con acetato de medroxiprogesterona (MAP), durante 11 días. Además, 48 horas antes del retiro de la esponja se administró 300 UI de gonadotropina coriónica equina (eCG) y 125 µg de cloprostenol. Las cabras que mostraron celo fueron sometidas a un empadre controlado por monta natural. El diagnóstico de gestación se hizo 60 días después de la monta mediante ultrasonografía transrectal. La tasa de presentación de celo fue de 86.7 y 96.7% para la época de anestro (enero-febrero) y ciclicidad (marzo-abril), respectivamente, sin diferencia significativa entre periodos. La tasa de concepción fue de 88.5 y 62.1% para los periodos enero-febrero y marzo-abril, respectivamente (p<0.05). Se concluye que el uso de esponjas intravaginales impregnadas con MAP para la sincronización del estro en cabras Saanen es eficaz, independientemente de la época del año
Efficacy of Three Low-Intensity, Internet-Based Psychological Interventions for the Treatment of Depression in Primary Care: Randomized Controlled Trial
BACKGROUND: Primary care is a major access point for the initial treatment of depression, but the management of these patients is far from optimal. The lack of time in primary care is one of the major difficulties for the delivery of evidence-based psychotherapy. During the last decade, research has focused on the development of brief psychotherapy and cost-effective internet-based interventions mostly based on cognitive behavioral therapy (CBT). Very little research has focused on alternative methods of treatment for depression using CBT. Thus, there is a need for research into other therapeutic approaches. OBJECTIVE: This study aimed to assess the effectiveness of 3 low-intensity, internet-based psychological interventions (healthy lifestyle psychoeducational program [HLP], focused program on positive affect promotion [PAPP], and brief intervention based on mindfulness [MP]) compared with a control condition (improved treatment as usual [iTAU]). METHODS: A multicenter, 4-arm, parallel randomized controlled trial was conducted between March 2015 and March 2016, with a follow-up of 12 months. In total, 221 adults with mild or moderate major depression were recruited in primary care settings from 3 Spanish regions. Patients were randomly distributed to iTAU (n=57), HLP (n=54), PAPP (n=56), and MP (n=54). All patients received iTAU from their general practitioners. The main outcome was the Spanish version of the Patient Health Questionnaire-9 (PHQ-9) from pretreatment (time 1) to posttreatment (time 2) and up to 6 (time 3) and 12 (time 4) months'' follow-up. Secondary outcomes included the visual analog scale of the EuroQol, the Short-Form Health Survey (SF-12), the Positive and Negative Affect Schedule (PANAS), and the Pemberton Happiness Index (PHI). We conducted regression models to estimate outcome differences along study stages. RESULTS: A moderate decrease was detected in PHQ-9 scores from HLP (ß=-3.05; P=.01) and MP (ß=-3.00; P=.01) compared with iTAU at posttreatment. There were significant differences between all intervention groups and iTAU in physical SF-12 scores at 6 months after treatment. Regarding well-being, MP and PAPP reported better PHI results than iTAU at 6 months post treatment. PAPP intervention significantly decreased PANAS negative affect scores compared with iTAU 12 months after treatment. CONCLUSIONS: The low-intensity, internet-based psychological interventions (HLP and MP) for the treatment of depression in primary care are more effective than iTAU at posttreatment. Moreover, all low-intensity psychological interventions are also effective in improving medium- and long-term quality of life. PAPP is effective for improving health-related quality of life, negative affect, and well-being in patients with depression. Nevertheless, it is important to examine possible reasons that could be implicated for PAPP not being effective in reducing depressive symptomatology; in addition, more research is still needed to assess the cost-effectiveness analysis of these interventions
Rituximab in Combination with Corticosteroids for the Treatment of Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis: A NICE Single Technology Appraisal
As part of its single technology appraisal (STA) process, the National Institute for Health and Care Excellence (NICE) invited the manufacturer of rituximab (Roche Products) to submit evidence of the clinical and cost effectiveness of rituximab in combination with corticosteroids for treatment of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). The School of Health and Related Research Technology Appraisal Group at the University of Sheffield was commissioned to act as the independent Evidence Review Group (ERG). The ERG produced a critical review of the evidence for the clinical and cost effectiveness of the technology, based upon the manufacturer’s submission to NICE. The evidence was derived mainly from a double-blind, phase III, placebo-controlled trial of rituximab in patients with new or relapsed ‘severe’ AAV, which compared a rituximab treatment regimen with an oral cyclophosphamide treatment regimen. Intravenous cyclophosphamide is also commonly used but was not included in the pivotal trial. The evidence showed that rituximab is noninferior to oral cyclophosphamide in terms of induction of remission in adults with AAV and de novo disease, and is superior to oral cyclophosphamide in terms of remission in adults who have relapsed once on cyclophosphamide. The ERG concluded that the results of the manufacturer’s economic evaluation could not be considered robust, because of errors and because the full range of relevant treatment sequences were not modelled. The ERG amended the manufacturer’s model and demonstrated that rituximab was likely to represent a cost-effective addition to the treatment sequence if given after cyclophosphamide treatment
Recommended from our members
International evaluation of an AI system for breast cancer screening.
Screening mammography aims to identify breast cancer at earlier stages of the disease, when treatment can be more successful1. Despite the existence of screening programmes worldwide, the interpretation of mammograms is affected by high rates of false positives and false negatives2. Here we present an artificial intelligence (AI) system that is capable of surpassing human experts in breast cancer prediction. To assess its performance in the clinical setting, we curated a large representative dataset from the UK and a large enriched dataset from the USA. We show an absolute reduction of 5.7% and 1.2% (USA and UK) in false positives and 9.4% and 2.7% in false negatives. We provide evidence of the ability of the system to generalize from the UK to the USA. In an independent study of six radiologists, the AI system outperformed all of the human readers: the area under the receiver operating characteristic curve (AUC-ROC) for the AI system was greater than the AUC-ROC for the average radiologist by an absolute margin of 11.5%. We ran a simulation in which the AI system participated in the double-reading process that is used in the UK, and found that the AI system maintained non-inferior performance and reduced the workload of the second reader by 88%. This robust assessment of the AI system paves the way for clinical trials to improve the accuracy and efficiency of breast cancer screening.Professor Fiona Gilbert receives funding from the National Institute for Health Research (Senior Investigator award)
Ror2 Enhances Polarity and Directional Migration of Primordial Germ Cells
The trafficking of primordial germ cells (PGCs) across multiple embryonic structures to the nascent gonads ensures the transmission of genetic information to the next generation through the gametes, yet our understanding of the mechanisms underlying PGC migration remains incomplete. Here we identify a role for the receptor tyrosine kinase-like protein Ror2 in PGC development. In a Ror2 mouse mutant we isolated in a genetic screen, PGC migration and survival are dysregulated, resulting in a diminished number of PGCs in the embryonic gonad. A similar phenotype in Wnt5a mutants suggests that Wnt5a acts as a ligand to Ror2 in PGCs, although we do not find evidence that WNT5A functions as a PGC chemoattractant. We show that cultured PGCs undergo polarization, elongation, and reorientation in response to the chemotactic factor SCF (secreted KitL), whereas Ror2 PGCs are deficient in these SCF-induced responses. In the embryo, migratory PGCs exhibit a similar elongated geometry, whereas their counterparts in Ror2 mutants are round. The protein distribution of ROR2 within PGCs is asymmetric, both in vitro and in vivo; however, this asymmetry is lost in Ror2 mutants. Together these results indicate that Ror2 acts autonomously to permit the polarized response of PGCs to KitL. We propose a model by which Wnt5a potentiates PGC chemotaxis toward secreted KitL by redistribution of Ror2 within the cell
Recommendations for vaccination in patients with multiple sclerosis who are eligible for immunosuppressive therapies: Spanish consensus statement
Background: The recent development of highly effective treatments for multiple sclerosis (MS) and the potential risk of infectious complications require the development of prevention and risk minimisation strategies. Vaccination is an essential element of the management of these patients. This consensus statement includes a series of recommendations and practical scenarios for the vaccination of adult patients with MS who are eligible for highly effective immunosuppressive treatments. Methodology: A formal consensus procedure was followed. Having defined the scope of the statement, we conducted a literature search on recommendations for the vaccination of patients with MS and specific vaccination guidelines for immunosuppressed patients receiving biological therapy for other conditions. The modified nominal group technique methodology was used to formulate the recommendations. Development: Vaccination in patients who are candidates for immunosuppressive therapy should be considered before starting immunosuppressive treatment providing the patient's clinical situation allows. Vaccines included in the routine adult vaccination schedule, as well as some specific ones, are recommended depending on the pre-existing immunity status. If immunosuppressive treatment is already established, live attenuated vaccines are contraindicated. For vaccines with a correlate of protection, it is recommended to monitor the serological response in an optimal interval of 1-2 months from the last dose.Antecedentes: La reciente aparición de terapias de alta efectividad para el tratamiento de la esclerosis múltiple (EM), con potencial riesgo de complicaciones infecciosas, obliga plantear estrategias de prevención y minimización de riesgos. La vacunación constituye una parte esencial del manejo de estos pacientes. Este consenso recoge una serie de pautasy escenarios prácticos de vacunación en pacientes adultos con EM candidatos a tratamiento inmunosupresor. Metodología: Se llevó a cabo un consenso de tipo formal. Tras definir el alcance del documento, se realizó una búsqueda bibliográfica de vacunación en pacientes con EM, así como guías de vacunación específicas de pacientes inmunosuprimidosy en tratamiento biológico con otras enfermedades.Para la formulación de las recomendaciones se empleó la metodología de Modified Nominal Group Technique. Desarrollo: La vacunación en pacientes candidatos a tratamiento inmunosupresor se debe plantear antes de iniciar un tratamiento inmunosupresor siempre que la situación clínica del paciente lo permita. Se recomendarán tanto aquellas indicadas en el calendario vacunal del adulto, como algunas específicas, en función de la inmunidad previa. Si ya está instaurado el tratamiento inmunosupresor las vacunas vivas atenuadas estarán contraindicadas.Para aquellas vacunas que dispongan de un correlato de protección se recomienda monitorizar la respuesta serológica transcurridos de uno a2 meses de la última dosi
- …