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•Articles related to the adsorption of proteins to nanomaterials are reviewed.•Examples from the last 10 years are discussed focused on biosensors.•Article includes general ...information about the proteins and emerging trends.
An important consideration for the development of biosensors is the adsorption of the biorecognition element to the surface of a substrate. As the first step in the immobilization process, adsorption affects most immobilization routes and much attention is given into the research of this process to maximize the overall activity of the biosensor. The use of nanomaterials, specifically nanoparticles and nanostructured films, offers advantageous properties that can be fine-tuned to maximize interactions with specific proteins to maximize activity, minimize structural changes, and enhance the catalytic step. In the biosensor field, protein–nanomaterial interactions are an emerging trend that span across many disciplines. This review addresses recent publications about the proteins most frequently used, their most relevant characteristics, and the conditions required to adsorb them to nanomaterials. When relevant and available, subsequent analytical figures of merits are discussed for selected biosensors. The general trend amongst the research papers allows concluding that the use of nanomaterials has already provided significant improvements in the analytical performance of many biosensors and that this research field will continue to grow.
Endoscopic variceal ligation plus beta‐blockers (EVL+BB) is currently recommended for variceal rebleeding prophylaxis, a recommendation that extends to all patients with cirrhosis with previous ...variceal bleeding irrespective of prognostic stage. Individualizing patient care is relevant, and in published studies on variceal rebleeding prophylaxis, there is a lack of information regarding response to therapy by prognostic stage. This study aimed at comparing EVL plus BB with monotherapy (EVL or BB) on all‐source rebleeding and mortality in patients with cirrhosis and previous variceal bleeding stratified by cirrhosis severity (Child A versus B/C) by means of individual time‐to‐event patient data meta‐analysis from randomized controlled trials. The study used individual data on 389 patients from three trials comparing EVL plus BB versus BB and 416 patients from four trials comparing EVL plus BB versus EVL. Compared with BB alone, EVL plus BB reduced overall rebleeding in Child A (incidence rate ratio 0.40; 95% confidence interval, 0.18‐0.89; P = 0.025) but not in Child B/C, without differences in mortality. The effect of EVL on rebleeding was different according to Child (P for interaction <0.001). Conversely, compared with EVL, EVL plus BB reduced rebleeding in both Child A and B/C, with a significant reduction in mortality in Child B/C (incidence rate ratio 0.46; 95% confidence interval, 0.25‐0.85; P = 0.013). Conclusion: Outcomes of therapies to prevent variceal rebleeding differ depending on cirrhosis severity: in patients with preserved liver function (Child A), combination therapy is recommended because it is more effective in preventing rebleeding, without modifying survival, while in patients with advanced liver failure (Child B/C), EVL alone carries an increased risk of rebleeding and death compared with combination therapy, underlining that BB is the key element of combination therapy. (Hepatology 2017;66:1219‐1231).
Persistence of Zika Virus in Body Fluids — Final Report Paz-Bailey, Gabriela; Rosenberg, Eli S; Doyle, Kate ...
New England journal of medicine/The New England journal of medicine,
09/2018, Letnik:
379, Številka:
13
Journal Article
Recenzirano
Odprti dostop
Zika virus has spread rapidly through the Americas during the past few years. In this final report, systematic assessment of ZIKV in different body sites is measured. ZIKV is commonly found in serum, ...urine, and semen and often persists for 2 to 6 weeks.
The microbiome has a crucial influence on host phenotype and is of broad interest to ecological and evolutionary research. Yet, the extent of variation that occurs in the microbiome within and ...between populations is unclear. We characterized the skin and gut microbiomes of seven populations of juvenile Atlantic salmon (
) inhabiting a diverse range of environments, including hatchery-reared and wild populations. We found shared skin operational taxonomic units (OTUs) across all populations and core gut microbiota for all wild fish, but the diversity and structure of both skin and gut microbial communities were distinct between populations. There was a marked difference between the gut microbiomes of wild and captive fish. Hatchery-reared fish had lower intestinal microbial diversity, lacked core microbiota found in wild fish, and showed altered community structure and function. Skin and gut microbiomes were also less varied within captive populations, reflecting more uniform artificial rearing conditions. The surrounding water influenced the microbiome of the gut and, especially, the skin, but could not explain the degree of variation observed between populations. For both gut and skin, we found that there was greater difference in microbiome structures between more genetically distinct fish populations, and that population genetic diversity was positively correlated with microbiome diversity. However, diet is likely to be the major factor contributing to the large differences in gut microbiota between wild and captive fish. Our results highlight the scope of interpopulation variation in the Atlantic salmon microbiome and offer insights into the deterministic factors contributing to microbiome diversity and structure.
Variation in the microbiome has a fundamental influence on host health, ecology, and evolution, but the scope and basis of this variation are not fully understood. We identified considerable variation in skin and gut microbial communities between seven wild and captive populations of Atlantic salmon, reflecting divergent environmental conditions and fish genetic diversity. In particular, we found very pronounced differences in the intestinal microbiomes of wild and hatchery-reared fish, likely reflecting differences in diet. Our results offer an insight into how the microbiome potentially contributes to the generation of local adaptations in this species and how domestication alters intestinal microbial communities, highlighting future research directions in these areas.
A growing number of cities are implementing bike-sharing programs to increase bicycle use. One of the key factors for the success of such programs is the location of bike stations in relation to ...potential demand (population, activities and public transport stations). This study proposes a GIS-based method to calculate the spatial distribution of the potential demand for trips, locate stations using location–allocation models, determine station capacity and define the characteristics of the demand for stations. The results obtained are compared with the most commonly used location–allocation modeling approaches: minimizing impedance and maximizing coverage. For the objective of this study, the latter approach is more useful. Diminishing returns are observed in both cases: as the number of stations increases, there is less improvement in the fraction of the population covered and accessibility to stations. Because the spatial structure of the proposed network also plays an important role in bike-station use, an additional accessibility analysis was carried out to calculate the volume of activity to which a station has access. With this analysis, stations that are relatively isolated, and therefore of little use to potential users, can be eliminated.
► GIS methodology to determine the optimal location of stations in bike-sharing programs. ► We calculate the spatial distribution of the potential demand for bicycle trips. ► We use location–allocation models in different scenarios and with different solutions. ► The main characteristics and the accessibility of each station are measured.
Unlike conventional thermally activated delayed fluorescence chromophores, boron-centered azatriangulene-like molecules combine a small excited-state singlet-triplet energy gap with high oscillator ...strengths and minor reorganization energies. Here, using highly correlated quantum-chemical calculations, we report this is driven by short-range reorganization of the electron density taking place upon electronic excitation of these multi-resonant structures. Based on this finding, we design a series of π-extended boron- and nitrogen-doped nanographenes as promising candidates for efficient thermally activated delayed fluorescence emitters with concomitantly decreased singlet-triplet energy gaps, improved oscillator strengths and core rigidity compared to previously reported structures, permitting both emission color purity and tunability across the visible spectrum.
Conductive metal-organic frameworks are of current interest in chemical science because of their applications in chemiresistive sensing, electrochemical energy storage, electrocatalysis, etc. ...Different strategies have been employed to design conductive frameworks. In this review, we discuss the influence of different types of guest species incorporated within the pores or channels of metal-organic frameworks (MOFs) and porous coordination polymers (PCPs) to generate charge transfer pathways and modulate their electrical conductivity. We have classified dopants or guest species into three different categories: (i) metal-based dopants, (ii) molecule and molecular entities and (iii) organic conducting polymers. Different types of metal ions, metal nano-clusters and metal oxides have been used to enhance electrical conductivity in MOFs. Metal ions and metal nano-clusters depend on the hopping process for efficient charge transfer whereas metal-oxides show charge transport through the metal-oxygen pathway. Several types of molecules or molecular entities ranging from neutral TCNQ, I2, and fullerene to ionic methyl viologen, organometallic like nickelcarborane, etc. have been used. In these cases, the charge transfer process varies with the guest species. When organic conducting polymers are the guest, the charge transport occurs through the polymer chains, mostly based on extended π-conjugation. Here we provide a comprehensive and critical review of these strategies to add electrical conductivity to the, in most cases, otherwise insulating MOFs and PCPs. We point out the guest encapsulation process, the geometry and structure of the resulting host-guest complex, the host-guest interactions and the charge transport mechanism for each case. We also present the methods for thin film fabrication of conducting MOFs (both, liquid-phase and gas-phase based methods) and their most relevant applications like electrocatalysis, sensing, charge storage, photoconductivity, photocatalysis,… We end this review with the main obstacles and challenges to be faced and the appealing perspectives of these 21st century materials.Conductive metal-organic frameworks are of current interest in chemical science because of their applications in chemiresistive sensing, electrochemical energy storage, electrocatalysis, etc. Different strategies have been employed to design conductive frameworks. In this review, we discuss the influence of different types of guest species incorporated within the pores or channels of metal-organic frameworks (MOFs) and porous coordination polymers (PCPs) to generate charge transfer pathways and modulate their electrical conductivity. We have classified dopants or guest species into three different categories: (i) metal-based dopants, (ii) molecule and molecular entities and (iii) organic conducting polymers. Different types of metal ions, metal nano-clusters and metal oxides have been used to enhance electrical conductivity in MOFs. Metal ions and metal nano-clusters depend on the hopping process for efficient charge transfer whereas metal-oxides show charge transport through the metal-oxygen pathway. Several types of molecules or molecular entities ranging from neutral TCNQ, I2, and fullerene to ionic methyl viologen, organometallic like nickelcarborane, etc. have been used. In these cases, the charge transfer process varies with the guest species. When organic conducting polymers are the guest, the charge transport occurs through the polymer chains, mostly based on extended π-conjugation. Here we provide a comprehensive and critical review of these strategies to add electrical conductivity to the, in most cases, otherwise insulating MOFs and PCPs. We point out the guest encapsulation process, the geometry and structure of the resulting host-guest complex, the host-guest interactions and the charge transport mechanism for each case. We also present the methods for thin film fabrication of conducting MOFs (both, liquid-phase and gas-phase based methods) and their most relevant applications like electrocatalysis, sensing, charge storage, photoconductivity, photocatalysis,… We end this review with the main obstacles and challenges to be faced and the appealing perspectives of these 21st century materials.
Summary
During the past decade, melanins and melanogenesis have attracted growing interest for a broad range of biomedical and technological applications. The burst of polydopamine‐based ...multifunctional coatings in materials science is just one example, and the list may be expanded to include melanin thin films for organic electronics and bioelectronics, drug delivery systems, functional nanoparticles and biointerfaces, sunscreens, environmental remediation devices. Despite considerable advances, applied research on melanins and melanogenesis is still far from being mature. A closer intersectoral interaction between research centers is essential to raise the interests and increase the awareness of the biomedical, biomaterials science and hi‐tech sectors of the manifold opportunities offered by pigment cells and related metabolic pathways. Starting from a survey of biological roles and functions, the present review aims at providing an interdisciplinary perspective of melanin pigments and related pathway with a view to showing how it is possible to translate current knowledge about physical and chemical properties and control mechanisms into new bioinspired solutions for biomedical, dermocosmetic, and technological applications.
•We introduce three independent citizen science projects to document floods.•Crowdsourced images were used for discharge estimation or flood mapping.•The projects provide consistent feedback on the ...key drivers for success.•Especially: the support of stakeholders and the public awareness of natural hazards.
New communication and digital image technologies have enabled the public to produce large quantities of flood observations and share them through social media. In addition to flood incident reports, valuable hydraulic data such as the extent and depths of inundated areas and flow rate estimates can be computed using messages, photos and videos produced by citizens. Such crowdsourced data help improve the understanding and modelling of flood hazard. Since little feedback on similar initiatives is available, we introduce three recent citizen science projects which have been launched independently by research organisations to quantitatively document flood flows in catchments and urban areas of Argentina, France, and New Zealand. Key drivers for success appear to be: a clear and simple procedure, suitable tools for data collecting and processing, an efficient communication plan, the support of local stakeholders, and the public awareness of natural hazards.
Sustained virological response (SVR) improves survival in post‐liver transplant (LT) recurrent hepatitis C. However, the impact of SVR on fibrosis regression is not well defined. In addition, the ...performance of noninvasive methods to evaluate the presence of fibrosis and portal hypertension (PH) post‐SVR has been scarcely evaluated. We aimed to investigate the degree of fibrosis regression (decrease ≥1 METAVIR stage) after‐SVR and its associated factors in recurrent hepatitis C, as well as the diagnostic capacity of noninvasive methods in the assessment of liver fibrosis and PH after viral clearance. We evaluated 112 hepatitis C virus–infected LT recipients who achieved SVR between 2001 and 2015. A liver biopsy was performed before treatment and 12 months post‐SVR. Hepatic venous pressure gradient (HVPG), liver stiffness measurement (LSM), and Enhanced Liver Fibrosis (ELF) score were also determined at the same time points. Sixty‐seven percent of the cohort presented fibrosis regression: 43% in recipients with cirrhosis and 72%‐85% in the remaining stages (P = 0.002). HVPG, LSM, and ELF significantly decreased post‐SVR. Liver function significantly improved, and survival was significantly better in patients achieving fibrosis regression. Baseline HVPG and LSM as well as decompensations before therapy were independent predictors of fibrosis regression. One year post‐SVR, LSM had a high diagnostic accuracy to discard the presence of advanced fibrosis (AF) and clinically significant PH (AUROC, 0.902 and 0.888). Conclusion: In conclusion, SVR post‐LT induces fibrosis regression in most patients, leading to significant clinical benefits. Pretreatment HVPG and LSM are significant determinants of the likelihood of fibrosis regression. Finally, LSM accurately predicts the presence of AF and PH 1 year after SVR and thus can be used to determine monitoring strategies. (Hepatology 2018;67:1683‐1694).
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