182 research outputs found
Novel effects of strains in graphene and other two dimensional materials
The analysis of the electronic properties of strained or lattice deformed
graphene combines ideas from classical condensed matter physics, soft matter,
and geometrical aspects of quantum field theory (QFT) in curved spaces. Recent
theoretical and experimental work shows the influence of strains in many
properties of graphene not considered before, such as electronic transport,
spin-orbit coupling, the formation of Moir\'e patterns, optics, ... There is
also significant evidence of anharmonic effects, which can modify the
structural properties of graphene. These phenomena are not restricted to
graphene, and they are being intensively studied in other two dimensional
materials, such as the metallic dichalcogenides. We review here recent
developments related to the role of strains in the structural and electronic
properties of graphene and other two dimensional compounds.Comment: 75 pages, 15 figures, review articl
IDENTIFICATION OF FOUR NEW SHARED SUSCEPTIBILITY GENES IN SYSTEMIC SCLEROSIS AND CROHN¿S DISEASE THROUGH A CROSS-DISEASE META-GWAS
CONSENSO SOBRE EL USO DE PROTEÍNA EN EL PACIENTE CRÍTICO – ACNC
El paciente crítico tiene una pérdida de masa muscular significativa, observando frecuentemente sarcopenia en estos pacientes. Su presencia aumenta los desenlaces adversos, estancias hospitalarias, mayor riesgo de infecciones, aumento del tiempo de asistencia ventilatoria mecánica, mayor discapacidad al alta hospitalaria, menor posibilidad del retorno normal a la vida habitual de los pacientes, incremento en gastos en salud y mayor mortalidad. Objetivo: Indicar el uso oportuno y adecuado de la proteína en el paciente crítico. Métodos: la Asociación Colombiana De Nutrición Clínica (ACNC) y la Asociación Colombiana de Medicina Critica y Cuidados Intensivos (AMCI) mediante metodología de consenso realizaron unas recomendaciones con un grupo de expertos. Resultados: 46 recomendaciones fueron aprobadas con consenso superior al 80%. Conclusiones: La intervención óptima proteica temprana y progresiva en el paciente crítico, es importante para obtener los mejores desenlaces clínicos, disminuir complicaciones e impactar en costos de atención hospitalaria.
Malignant melanoma arising from a perianal fistula and harbouring a BRAF gene mutation: a case report
<p>Abstract</p> <p>Background</p> <p>Melanoma of the anal region is a very uncommon disease, accounting for only 0.2-0.3% of all melanoma cases. Mutations of the <it>BRAF </it>gene are usually absent in melanomas occurring in this region as well as in other sun-protected regions. The development of a tumour in a longstanding perianal fistula is also extremely rare. More frequent is the case of a tumour presenting as a fistula, that is, the fistula being a consequence of the cancerous process, although we have found only two cases of fistula-generating melanomas reported in the literature.</p> <p>Case Presentation</p> <p>Here we report the case of a 38-year-old male who presented with a perianal fistula of four years of evolution. Histopathological examination of the fistulous tract confirmed the presence of malignant melanoma. Due to the small size and the central location of the melanoma inside the fistulous tract, we believe the melanoma reported here developed in the epithelium of the fistula once the latter was already formed. Resected sentinel lymph nodes were negative and the patient, after going through a wide local excision, remains disease-free nine years after diagnosis. DNA obtained from melanoma tissue was analysed by automated direct sequencing and the <it>V600E </it>(<it>T1799A</it>) mutation was detected in exon 15 of the <it>BRAF </it>gene.</p> <p>Conclusion</p> <p>Since fistulae experience persistent inflammation, the fact that this melanoma harbours a <it>BRAF </it>mutation strengthens the view that oxidative stress caused by inflammatory processes plays an important role in the genesis of <it>BRAF </it>gene mutations.</p
CONSENSO SOBRE O USO DE PROTEÍNA EM PACIENTES CRÍTICOS – ACNC
The critical patient has a significant loss of muscle mass, frequently observing sarcopenia in these patients. Its presence increases adverse outcomes, hospital stays, increased risk of infections, increased time on mechanical ventilatory assistance, greater disability at hospital discharge, less possibility of return to normal life for patients, increased health costs, and higher mortality. Objective: Indicate the opportune and adequate use of the protein in the critically ill patient. Methods: the Colombian Association of Clinical Nutrition (ACNC) and the Colombian Association of Critical Medicine and Intensive Care (AMCI), using a consensus methodology, made recommendations with a group of experts. Results: 46 recommendations were approved with a consensus greater than 80%. Conclusions: Optimal early and progressive protein intervention in critically ill patients is important to obtain the best clinical outcomes, reduce complications, and have an impact on hospital care costs.El paciente crítico tiene una pérdida de masa muscular significativa, observando frecuentemente sarcopenia en estos pacientes. Su presencia aumenta los desenlaces adversos, estancias hospitalarias, mayor riesgo de infecciones, aumento del tiempo de asistencia ventilatoria mecánica, mayor discapacidad al alta hospitalaria, menor posibilidad del retorno normal a la vida habitual de los pacientes, incremento en gastos en salud y mayor mortalidad. Objetivo: Indicar el uso oportuno y adecuado de la proteína en el paciente crítico. Métodos: la Asociación Colombiana De Nutrición Clínica (ACNC) y la Asociación Colombiana de Medicina Critica y Cuidados Intensivos (AMCI) mediante metodología de consenso realizaron unas recomendaciones con un grupo de expertos. Resultados: 46 recomendaciones fueron aprobadas con consenso superior al 80%. Conclusiones: La intervención óptima proteica temprana y progresiva en el paciente crítico, es importante para obtener los mejores desenlaces clínicos, disminuir complicaciones e impactar en costos de atención hospitalaria. O paciente crítico apresenta perda importante de massa muscular, observando-se frequentemente sarcopenia nesses pacientes. Sua presença aumenta os desfechos adversos, internações hospitalares, aumento do risco de infecções, aumento do tempo de assistência ventilatória mecânica, maior incapacidade na alta hospitalar, menor possibilidade de retorno à vida normal dos pacientes, aumento dos custos de saúde e maior mortalidade. Objetivo: Indicar o uso oportuno e adequado da proteína no paciente crítico. Métodos: a Associação Colombiana de Nutrição Clínica (ACNC) e a Associação Colombiana de Medicina Crítica e Terapia Intensiva (AMCI), utilizando uma metodologia de consenso, fizeram recomendações com um grupo de especialistas. Resultados: 46 recomendações foram aprovadas com consenso superior a 80%. Conclusões: A intervenção proteica precoce e progressiva ideal em pacientes críticos é importante para obter os melhores resultados clínicos, reduzir complicações e impactar nos custos hospitalares
The Splicing Factor Proline-Glutamine Rich (SFPQ/PSF) Is Involved in Influenza Virus Transcription
The influenza A virus RNA polymerase is a heterotrimeric complex responsible for viral genome transcription and replication in the nucleus of infected cells. We recently carried out a proteomic analysis of purified polymerase expressed in human cells and identified a number of polymerase-associated cellular proteins. Here we characterise the role of one such host factors, SFPQ/PSF, during virus infection. Down-regulation of SFPQ/PSF by silencing with two independent siRNAs reduced the virus yield by 2–5 log in low-multiplicity infections, while the replication of unrelated viruses as VSV or Adenovirus was almost unaffected. As the SFPQ/PSF protein is frequently associated to NonO/p54, we tested the potential implication of the latter in influenza virus replication. However, down-regulation of NonO/p54 by silencing with two independent siRNAs did not affect virus yields. Down-regulation of SFPQ/PSF by siRNA silencing led to a reduction and delay of influenza virus gene expression. Immunofluorescence analyses showed a good correlation between SFPQ/PSF and NP levels in infected cells. Analysis of virus RNA accumulation in silenced cells showed that production of mRNA, cRNA and vRNA is reduced by more than 5-fold but splicing is not affected. Likewise, the accumulation of viral mRNA in cicloheximide-treated cells was reduced by 3-fold. In contrast, down-regulation of SFPQ/PSF in a recombinant virus replicon system indicated that, while the accumulation of viral mRNA is reduced by 5-fold, vRNA levels are slightly increased. In vitro transcription of recombinant RNPs generated in SFPQ/PSF-silenced cells indicated a 4–5-fold reduction in polyadenylation but no alteration in cap snatching. These results indicate that SFPQ/PSF is a host factor essential for influenza virus transcription that increases the efficiency of viral mRNA polyadenylation and open the possibility to develop new antivirals targeting the accumulation of primary transcripts, a very early step during infection
In Vitro and In Vivo High-Throughput Assays for the Testing of Anti-Trypanosoma cruzi Compounds
The treatment of Trypanosoma cruzi infection (the cause of human Chagas disease) remains a significant challenge. Only two drugs, both with substantial toxicity, are available and the efficacy of these dugs is often questioned – in many cases due to the limitations of the methods for assessing efficacy rather than to true lack of efficacy. For these reasons relatively few individuals infected with T. cruzi actually have their infections treated. In this study, we report on innovative methods that will facilitate the discovery of new compounds for the treatment of T. cruzi infection and Chagas disease. Utilizing fluorescent and bioluminescent parasite lines, we have developed in vitro tests that are reproducible and facile and can be scaled for high-throughput screening of large compound libraries. We also validate an in vivo screening test that monitors parasite replication at the site of infection and determines the effectiveness of drug treatment in less than two weeks. More importantly, results in this rapid in vivo test show strong correlations with those obtained in long-term (e.g. 40 day or more) treatment assays. The results of this study remove one of the obstacles for identification of effective and safe compounds to treat Chagas disease
The global contribution of soil mosses to ecosystem services
Soil mosses are among the most widely distributed organisms on land. Experiments and observations suggest that they contribute to terrestrial soil biodiversity and function, yet their ecological contribution to soil has never been assessed globally under natural conditions. Here we conducted the most comprehensive global standardized field study to quantify how soil mosses influence 8 ecosystem services associated with 24 soil biodiversity and functional attributes across wide environmental gradients from all continents. We found that soil mosses are associated with greater carbon sequestration, pool sizes for key nutrients and organic matter decomposition rates but a lower proportion of soil-borne plant pathogens than unvegetated soils. Mosses are especially important for supporting multiple ecosystem services where vascular-plant cover is low. Globally, soil mosses potentially support 6.43 Gt more carbon in the soil layer than do bare soils. The amount of soil carbon associated with mosses is up to six times the annual global carbon emissions from any altered land use globally. The largest positive contribution of mosses to soils occurs under a high cover of mat and turf mosses, in less-productive ecosystems and on sandy and salty soils. Our results highlight the contribution of mosses to soil life and functions and the need to conserve these important organisms to support healthy soils.The study work associated with this paper was funded by a Large Research Grant from the British Ecological Society (no. LRB17\1019; MUSGONET). D.J.E. is supported by the Hermon Slade Foundation. M.D.-B. was supported by a Ramón y Cajal grant from the Spanish Ministry of Science and Innovation (RYC2018-025483-I), a project from the Spanish Ministry of Science and Innovation for the I + D + i (PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033a) and a project PAIDI 2020 from the Junta de Andalucía (P20_00879). E.G. is supported by the European Research Council grant agreement 647038 (BIODESERT). M.B. is supported by a Ramón y Cajal grant from Spanish Ministry of Science (RYC2021-031797-I). A.d.l.R is supported by the AEI project PID2019-105469RB-C22. L.W. and Jianyong Wang are supported by the Program for Introducing Talents to Universities (B16011) and the Ministry of Education Innovation Team Development Plan (2013-373). The contributions of T.G. and T.U.N. were supported by the Research Program in Forest Biology, Ecology and Technology (P4-0107) and the research projects J4-3098 and J4-4547 of the Slovenian Research Agency. The contribution of P.B.R. was supported by the NSF Biological Integration Institutes grant DBI-2021898. J. Durán and A. Rodríguez acknowledge support from the FCT (2020.03670.CEECIND and SFRH/BDP/108913/2015, respectively), as well as from the MCTES, FSE, UE and the CFE (UIDB/04004/2021) research unit financed by FCT/MCTES through national funds (PIDDAC)
Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).
Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)
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