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Discerning the effect of pharmacological exposures on intestinal bacterial communities in cancer patients is challenging. Here, we deconvoluted the relationship between drug exposures and changes in microbial composition by developing and applying a new computational method, PARADIGM (parameters associated with dynamics of gut microbiota), to a large set of longitudinal fecal microbiome profiles with detailed medication-administration records from patients undergoing allogeneic hematopoietic cell transplantation. We observed that several non-antibiotic drugs, including laxatives, antiemetics, and opioids, are associated with increased Enterococcus relative abundance and decreased alpha diversity. Shotgun metagenomic sequencing further demonstrated subspecies competition, leading to increased dominant-strain genetic convergence during allo-HCT that is significantly associated with antibiotic exposures. We integrated drug-microbiome associations to predict clinical outcomes in two validation cohorts on the basis of drug exposures alone, suggesting that this approach can generate biologically and clinically relevant insights into how pharmacological exposures can perturb or preserve microbiota composition. The application of a computational method called PARADIGM to a large dataset of cancer patients' longitudinal fecal specimens and detailed daily medication records reveals associations between drug exposures and the intestinal microbiota that recapitulate in vitro findings and are also predictive of clinical outcomes.
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Microbioma Gastrointestinal , Trasplante de Células Madre Hematopoyéticas , Microbiota , Neoplasias , Humanos , Microbioma Gastrointestinal/genética , Heces/microbiología , Metagenoma , Antibacterianos , Neoplasias/tratamiento farmacológicoRESUMEN
Many critical biological processes take place at hydrophobic:hydrophilic interfaces, and a wide range of organisms produce surface-active proteins and peptides that reduce surface and interfacial tension and mediate growth and development at these boundaries. Microorganisms produce both small lipid-associated peptides and amphipathic proteins that allow growth across water:air boundaries, attachment to surfaces, predation, and improved bioavailability of hydrophobic substrates. Higher-order organisms produce surface-active proteins with a wide variety of functions, including the provision of protective foam environments for vulnerable reproductive stages, evaporative cooling, and gas exchange across airway membranes. In general, the biological functions supported by these diverse polypeptides require them to have an amphipathic nature, and this is achieved by a diverse range of molecular structures, with some proteins undergoing significant conformational change or intermolecular association to generate the structures that are surface active.
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Caseínas/química , Glicoproteínas/química , Proteínas de la Membrana/química , Proteínas de Neoplasias/química , Fosfoproteínas/química , Surfactantes Pulmonares/química , Tensoactivos/química , Animales , Bacterias/química , Bacterias/genética , Bacterias/metabolismo , Caseínas/genética , Caseínas/metabolismo , Hongos/química , Hongos/genética , Hongos/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Mamíferos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Conformación Proteica , Surfactantes Pulmonares/metabolismo , Propiedades de Superficie , Tensoactivos/metabolismo , Agua/química , Agua/metabolismoRESUMEN
Transition metal borides, carbides, pnictides, and chalcogenides (X-ides) have emerged as a class of materials for the oxygen evolution reaction (OER). Because of their high earth abundance, electrical conductivity, and OER performance, these electrocatalysts have the potential to enable the practical application of green energy conversion and storage. Under OER potentials, X-ide electrocatalysts demonstrate various degrees of oxidation resistance due to their differences in chemical composition, crystal structure, and morphology. Depending on their resistance to oxidation, these catalysts will fall into one of three post-OER electrocatalyst categories: fully oxidized oxide/(oxy)hydroxide material, partially oxidized core@shell structure, and unoxidized material. In the past ten years (from 2013 to 2022), over 890 peer-reviewed research papers have focused on X-ide OER electrocatalysts. Previous review papers have provided limited conclusions and have omitted the significance of "catalytically active sites/species/phases" in X-ide OER electrocatalysts. In this review, a comprehensive summary of (i) experimental parameters (e.g., substrates, electrocatalyst loading amounts, geometric overpotentials, Tafel slopes, etc.) and (ii) electrochemical stability tests and post-analyses in X-ide OER electrocatalyst publications from 2013 to 2022 is provided. Both mono and polyanion X-ides are discussed and classified with respect to their material transformation during the OER. Special analytical techniques employed to study X-ide reconstruction are also evaluated. Additionally, future challenges and questions yet to be answered are provided in each section. This review aims to provide researchers with a toolkit to approach X-ide OER electrocatalyst research and to showcase necessary avenues for future investigation.
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The RIP homotypic interaction motif (RHIM) is an essential protein motif in inflammatory signaling and certain cell death pathways. RHIM signaling occurs following the assembly of functional amyloids, and while the structural biology of such higher-order RHIM complexes has started to emerge, the conformations and dynamics of nonassembled RHIMs remain unknown. Here, using solution NMR spectroscopy, we report the characterization of the monomeric form of the RHIM in receptor-interacting protein kinase 3 (RIPK3), a fundamental protein in human immunity. Our results establish that the RHIM of RIPK3 is an intrinsically disordered protein motif, contrary to prediction, and that exchange dynamics between free monomers and amyloid-bound RIPK3 monomers involve a 20-residue stretch outside the RHIM that is not incorporated within the structured cores of the RIPK3 assemblies determined by cryo-EM or solid-state NMR. Thus, our findings expand on the structural characterization of RHIM-containing proteins, specifically highlighting conformational dynamics involved in assembly processes.
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Amiloide , Proteínas Amiloidogénicas , Humanos , Amiloide/química , Muerte Celular , Proteínas Amiloidogénicas/metabolismo , Transducción de Señal , Espectroscopía de Resonancia Magnética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismoRESUMEN
BACKGROUND: Shorter prophylactic vaccine schedules may offer more rapid protection against Ebola in resource-limited settings. METHODS: This randomized, observer-blind, placebo-controlled, phase 2 trial conducted in five sub-Saharan African countries included people without HIV (PWOH, n = 249) and people living with HIV (PLWH, n = 250). Adult participants received one of two accelerated Ebola vaccine regimens (MVA-BN-Filo, Ad26.ZEBOV administered 14 days apart [n = 79] or Ad26.ZEBOV, MVA-BN-Filo administered 28 days apart [n = 322]) or saline/placebo (n = 98). The primary endpoints were safety (adverse events [AEs]) and immunogenicity (Ebola virus [EBOV] glycoprotein-specific binding antibody responses). Binding antibody responders were defined as participants with a > 2.5-fold increase from baseline or the lower limit of quantification if negative at baseline. RESULTS: The mean age was 33.4 years, 52% of participants were female, and among PLWH, the median (interquartile range) CD4+ cell count was 560.0 (418.0-752.0) cells/µL. AEs were generally mild/moderate with no vaccine-related serious AEs or remarkable safety profile differences by HIV status. At 21 days post-dose 2, EBOV glycoprotein-specific binding antibody response rates in vaccine recipients were 99% for the 14-day regimen (geometric mean concentrations [GMCs]: 5168 enzyme-linked immunosorbent assay units (EU)/mL in PWOH; 2509 EU/mL in PLWH), and 98% for the 28-day regimen (GMCs: 6037 EU/mL in PWOH; 2939 EU/mL in PLWH). At 12 months post-dose 2, GMCs in PWOH and PLWH were 635 and 514 EU/mL, respectively, for the 14-day regimen and 331 and 360 EU/mL, respectively, for the 28-day regimen. CONCLUSIONS: Accelerated 14- and 28-day Ebola vaccine regimens were safe and immunogenic in PWOH and PLWH in Africa. TRIAL REGISTRATION: NCT02598388.
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Low intestinal microbial diversity is associated with poor outcomes after allogeneic hematopoietic cell transplantation (HCT). Using 16S rRNA sequencing of 2067 stool samples and flow cytometry data from 2370 peripheral blood samples drawn from 894 patients who underwent allogeneic HCT, we have linked features of the early post-HCT microbiome with subsequent immune cell recovery. We examined lymphocyte recovery and microbiota features in recipients of both unmodified and CD34-selected allografts. We observed that fecal microbial diversity was an independent predictor of CD4 T-cell count 3 months after HCT in recipients of a CD34-selected allograft, who are dependent on de novo lymphopoiesis for their immune recovery. In multivariate models using clinical factors and microbiota features, we consistently observed that increased fecal relative abundance of genus Staphylococcus during the early posttransplant period was associated with worse CD4 T-cell recovery. Our observations suggest that the intestinal bacteria, or the factors they produce, can affect early lymphopoiesis and the homeostasis of allograft-derived T cells after transplantation.
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Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Linfocitos T CD4-Positivos , Humanos , Recuento de Linfocitos , ARN Ribosómico 16S , Trasplante HomólogoRESUMEN
Lateral growth of thin films is crucial for organic electronic devices, such as field-effect transistors. Here, we report a strategy to improve the lateral growth of pentacene films using rubrene as a surfactant-like additive. Atomic force microscopy (AFM) images confirm the enhanced lateral growth with the presence of rubrene, resulting in smooth and enlarged molecule domains in the films in comparison to those without rubrene. Molecular dynamics simulations are conducted to explore the interlayer diffusion of pentacene molecules during the growth. With the rubrene molecules as surfactant-like additives, mean square displacement (MSD) analysis shows that the pentacene molecules have a descending diffusion coefficient of 2.0 × 10-5 cm2 s-1, which is greater than the ascending diffusion coefficient of 1.6 × 10-5 cm2 s-1. The more descending molecules lead to an enhanced lateral growth of pentacene films, which is in good agreement with the experiments. As a result, the pentacene films grown with rubrene exhibit a rapid increase in carrier mobility over thickness due to the well-connected domains resulting from enhanced lateral growth. This finding will provide a new strategy to modulate the morphology of organic films for high-performance devices.
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Hydrophobins are remarkable proteins due to their ability to self-assemble into amphipathic coatings that reverse surface wettability. Here, the versatility of the Class I hydrophobins EASΔ15 and DewY in diverse nanosuspension and coating applications is demonstrated. The hydrophobins are shown to coat or emulsify a range of substrates including oil, hydrophobic drugs, and nanodiamonds and alter their solution and surface behavior. Surprisingly, while the coatings confer new properties, only a subset is found to be resistant to hot detergent treatment, a feature previously thought to be characteristic of the functional amyloid form of Class I hydrophobins. These results demonstrate that substrate surface properties can influence the molecular structures and physiochemical properties of hydrophobin and possibly other functional amyloids. Functional amyloid assembly with different substrates and conditions may be analogous to the propagation of different polymorphs of disease-associated amyloid fibrils with distinct structures, stability, and clinical phenotypes. Given that amyloid formation is not required for Class I hydrophobins to serve diverse applications, our findings open up new opportunities for their use in applications requiring a range of chemical and physical properties. In hydrophobin nanotechnological applications where high stability of assemblies is required, simultaneous structural and functional characterization should be carried out. Finally, while results in this study pertain to synthetic substrates, they raise the possibility that at least some members of the pseudo-Class I and Class III hydrophobins, reported to form assemblies with noncanonical properties, may be Class I hydrophobins adopting alternative structures in response to environmental cues.
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Amiloide , Proteínas Fúngicas , Proteínas Fúngicas/química , Humectabilidad , Interacciones Hidrofóbicas e Hidrofílicas , Propiedades de Superficie , Secuencia de Aminoácidos , Amiloide/química , Proteínas AmiloidogénicasRESUMEN
Objective: To compare the efficacy of off-pump minimally invasive cardiac surgery (MICS) via a single left intercostal space incision with median sternotomy multi-vesselcoronary artery bypass grafting (CABG). Methods: Patients who were diagnosed with multi-artery coronary artery disease (CAD) in the Ward 10 of the Department of Cardiac Surgery, Beijing Anzhen Hospital Affiliated to Capital Medical University and underwent CABG from July 2019 to January 2022 were retrospectively collected. All the patients were divided into MICS group and conventional CABG group according to the surgical methods. The perioperative outcomes were compared between thetwo groups, including intraoperative blood loss, postoperative 24 h thoracic drainage volume, ventilation duration, length of stay (LOS) in intensive care unit (ICU) and total LOS in hospital. Intraoperative blood flow of graft vesselswas measured by transit-time flow measurement (TTFM) after vascular anastomosis, and mean flow (MF) and pulsatile index (PI) were compared between the two groups. Results: A total of 444 patients were in the final analysis, with 351 males and 93 females, and the mean age of (62.0±8.9) years. There were 179 patients in MICS group and 265 cases in conventional CABG group, respectively. There were no statistically significant differences in the preoperative profiles between the two groups (all P>0.05) except that younger age [(60.7±9.3) years vs (62.8±8.5) years, P=0.017] and lower proportion of female [10.1% (18/179) vs 28.3% (75/265), P<0.001] were detected in MICS group. Likewise, there was no significant difference in the number of graft vessels between MICS group (3.18±0.74) and conventional CABG group (3.28±0.86) (P=0.234). Compared with those in conventional CABG group, patients in MICS group showed longer operation duration [ (5.10±1.09) h vs (4.33±0.86) h], fewer intraoperative blood loss [500 (200, 700) ml vs 700 (600, 900) ml], fewer postoperative 24 h thoracic drainage volume [300 (200, 400) ml vs 400 (250, 500) ml], shorter postoperative ventilation duration [15.0 (12.0, 17.0) h vs 16.5 (12.5, 19.0) h, P<0.001], LOS in ICU [18.0 (15.0, 20.0) h vs 20.0 (16.0, 23.0) h, P<0.001] and total LOS in hospital [(12.6±2.7) d vs (14.5±3.9) d, P<0.001]. MI and PI of graft vessels were similar between the two groups (both P>0.05). Moreover, there were no significant differences in major perioperative complications (i.e., repeat thoracotomy, incision infection, stroke) and mortality between the two groups (all P>0.05). Conclusion: MICS is an alternative treatment for patients with multi-vessel CAD with better perioperative outcomes compared with conventional CABG.
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Enfermedad de la Arteria Coronaria , Herida Quirúrgica , Masculino , Humanos , Femenino , Persona de Mediana Edad , Anciano , Esternotomía , Estudios Retrospectivos , Procedimientos Quirúrgicos Vasculares , Arterias , Enfermedad de la Arteria Coronaria/cirugía , Pérdida de Sangre QuirúrgicaRESUMEN
The Receptor-interacting protein kinase Homotypic Interaction Motif (RHIM) is an amino acid sequence that mediates multiple protein:protein interactions in the mammalian programmed cell death pathway known as necroptosis. At least one key RHIM-based complex has been shown to have a functional amyloid fibril structure, which provides a stable hetero-oligomeric platform for downstream signaling. RHIMs and related motifs are present in immunity-related proteins across nature, from viruses to fungi to metazoans. Necroptosis is a hallmark feature of cellular clearance of infection. For this reason, numerous pathogens, including viruses and bacteria, have developed varied methods to modulate necroptosis, focusing on inhibiting RHIM:RHIM interactions, and thus their downstream cell death effects. This review will discuss current understanding of RHIM:RHIM interactions in normal cellular activation of necroptosis, from a structural and cell biology perspective. It will compare the mechanisms by which pathogens subvert these interactions in order to maintain their replicative and infective cycles and consider the similarities between RHIMs and other functional amyloid-forming proteins associated with cell death and innate immunity. It will discuss the implications of the heteromeric nature and structure of RHIM-based amyloid complexes in the context of other functional amyloids.
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Apoptosis/inmunología , Necroptosis/inmunología , Proteína Serina-Treonina Quinasas de Interacción con Receptores/inmunología , Animales , Humanos , Inmunidad Innata/inmunología , Unión Proteica , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismoRESUMEN
BACKGROUND: Before the SARS-CoV-2 Delta variant arrived in Vietnam, case rates suggested seroprevalence of SARS-CoV-2 was low. Beginning in March 2021, we assessed different dosing schedules and adverse events following immunization (AEFIs) for ChAdOx1 nCoV-19 vaccine among healthcare workers (HCWs). METHODS: We performed a prospective cohort study to estimate the prevalence of IgG antibodies to SARS-CoV-2 before and after ChAdOx1 nCoV-19 vaccination. We conducted antibody testing among HCWs in February 2021 (baseline), before the second dose (June-July 2021), and 1 and 3 months after the second dose. We detected antibodies to SARS-CoV-2 using Tetracore® FlexImmArray™, and surrogate neutralizing antibodies using GenScript cPass™. Neither assay can distinguish natural from vaccine-induced antibodies. We assessed AEFIs through interview post-dose 1 and 1 month post-dose 2. RESULTS: Before vaccination, 1/617 participants (0.16%) had antibodies to SARS-CoV-2. Of these 617, 405 were vaccinated with ChAdOx1 nCoV-19 with 4-8- (60%), 9-12- (27%), or ≥13-week (13%) intervals between the 2 doses. Three months following series completion, 99% and 97% of vaccinated participants had ≥1 sample with detectable antibodies and surrogate neutralizing antibodies against SARS-CoV-2, respectively. We observed no significant differences among those with different dosing intervals at last follow-up. All participants reported PCR testing for SARS-CoV-2 during the study; 2 (0.5%) were laboratory-confirmed. AEFIs were more frequent post-dose 1 (81%) vs post-dose 2 (21%). CONCLUSIONS: In this population, regardless of dosing interval, ChAdOx1 nCoV-19 induced antibodies within 3 months of the second dose. These findings may offer flexibility to policymakers when balancing programmatic considerations with vaccine effectiveness.
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COVID-19 , Vacunas Virales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Pueblo Asiatico , COVID-19/epidemiología , COVID-19/prevención & control , ChAdOx1 nCoV-19 , Personal de Salud , Humanos , Inmunoglobulina G , Estudios Prospectivos , SARS-CoV-2 , Estudios Seroepidemiológicos , Vacunación , Vietnam/epidemiologíaRESUMEN
Herpesviruses are known to encode a number of inhibitors of host cell death, including RIP Homotypic Interaction Motif (RHIM)-containing proteins. Varicella zoster virus (VZV) is a member of the alphaherpesvirus subfamily and is responsible for causing chickenpox and shingles. We have identified a novel viral RHIM in the VZV capsid triplex protein, open reading frame (ORF) 20, that acts as a host cell death inhibitor. Like the human cellular RHIMs in RIPK1 and RIPK3 that stabilise the necrosome in TNF-induced necroptosis, and the viral RHIM in M45 from murine cytomegalovirus that inhibits cell death, the ORF20 RHIM is capable of forming fibrillar functional amyloid complexes. Notably, the ORF20 RHIM forms hybrid amyloid complexes with human ZBP1, a cytoplasmic sensor of viral nucleic acid. Although VZV can inhibit TNF-induced necroptosis, the ORF20 RHIM does not appear to be responsible for this inhibition. In contrast, the ZBP1 pathway is identified as important for VZV infection. Mutation of the ORF20 RHIM renders the virus incapable of efficient spread in ZBP1-expressing HT-29 cells, an effect which can be reversed by the inhibition of caspases. Therefore we conclude that the VZV ORF20 RHIM is important for preventing ZBP1-driven apoptosis during VZV infection, and propose that it mediates this effect by sequestering ZBP1 into decoy amyloid assemblies.
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Muerte Celular/fisiología , Herpesvirus Humano 3/metabolismo , Proteínas de Unión al ARN/metabolismo , Infección por el Virus de la Varicela-Zóster/metabolismo , Proteínas Virales/metabolismo , Animales , Humanos , RatonesRESUMEN
Angiotensin-(1-7) re-balance the Renin-Angiotensin system affected during several pathologies, including the new COVID-19; cardiovascular diseases; and cancer. However, one of the limiting factors for its therapeutic use is its short half-life, which might be overcome with the use of dendrimers as nanoprotectors. In this work, we addressed the following issues: (1) the capacity of our computational protocol to reproduce the experimental structural features of the (hydroxyl/amino)-terminated PAMAM dendrimers as well as the Angiotensin-(1-7) peptide; (2) the coupling of Angiotensin-(1-7) to (hydroxyl/amino)-terminated PAMAM dendrimers in order to gain insight into the structural basis of its molecular binding; (3) the capacity of the dendrimers to protect Angiotensin-(1-7); and (4) the effect of pH changes on the peptide binding and covering. Our Molecular-Dynamics/Metadynamics-based computational protocol well modeled the structural experimental features reported in the literature and our double-docking approach was able to provide reasonable initial structures for stable complexes. At neutral pH, PAMAM dendrimers with both terminal types were able to interact stably with 3 Angiotensin-(1-7) peptides through ASP1, TYR4 and PRO7 key amino acids. In general, they bind on the surface in the case of the hydroxyl-terminated compact dendrimer and in the internal zone in the case of the amino-terminated open dendrimer. At acidic pH, PAMAM dendrimers with both terminal groups are still able to interact with peptides either internalized or in its periphery, however, the number of contacts, the percentage of coverage and the number of hydrogen bonds are lesser than at neutral pH, suggesting a state for peptide release. In summary, amino-terminated PAMAM dendrimer showed slightly better features to bind, load and protect Angiotensin-(1-7) peptides.
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COVID-19 , Dendrímeros , Aminoácidos , Angiotensina I , Dendrímeros/química , Humanos , Simulación de Dinámica Molecular , Fragmentos de Péptidos , PéptidosRESUMEN
The Chloride Channel (CLC) family includes proton-coupled chloride and fluoride transporters. Despite their similar protein architecture, the former exchange two chloride ions for each proton and are inhibited by fluoride, whereas the latter efficiently transport one fluoride in exchange for one proton. The combination of structural, mutagenesis, and functional experiments with molecular simulations has pinpointed several amino acid changes in the permeation pathway that capitalize on the different chemical properties of chloride and fluoride to fine-tune protein function. Here we summarize recent findings on fluoride inhibition and transport in the two prototypical members of the CLC family, the chloride/proton transporter from Escherichia coli (CLC-ec1) and the fluoride/proton transporter from Enterococcus casseliflavus (CLCF-eca).
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TIR-domain-containing adapter-inducing interferon-ß (TRIF) is an innate immune protein that serves as an adaptor for multiple cellular signalling outcomes in the context of infection. TRIF is activated via ligation of Toll-like receptors 3 and 4. One outcome of TRIF-directed signalling is the activation of the programmed cell death pathway necroptosis, which is governed by interactions between proteins that contain a RIP Homotypic Interaction Motif (RHIM). TRIF contains a RHIM sequence and can interact with receptor interacting protein kinases 1 (RIPK1) and 3 (RIPK3) to initiate necroptosis. Here, we demonstrate that the RHIM of TRIF is amyloidogenic and supports the formation of homomeric TRIF-containing fibrils. We show that the core tetrad sequence within the RHIM governs the supramolecular organisation of TRIF amyloid assemblies, although the stable amyloid core of TRIF amyloid fibrils comprises a much larger region than the conserved RHIM only. We provide evidence that RHIMs of TRIF, RIPK1 and RIPK3 interact directly to form heteromeric structures and that these TRIF-containing hetero-assemblies display altered and emergent properties that likely underlie necroptosis signalling in response to Toll-like receptor activation.
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Amiloide , Necroptosis , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/genética , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Amiloide/metabolismo , Apoptosis/fisiologíaRESUMEN
Multiply bonded lanthanide oxo groups are rare in coordination compounds and have not previously been reported for a surface termination of a lanthanide oxide. Here we report the observation of a Ce=O terminated ceria surface in a CeO2 (111)-( 3 × 3 )R30° reconstruction of ≈3â nm thick ceria islands prepared on Pt(111). This is evidenced by scanning tunnelling microscopy (STM), low energy electron diffraction (LEED) and high-resolution electron energy loss spectroscopy (HREELS) measurements in conjunction with density functional theory (DFT) calculations. A Ce=O stretching frequency of 775â cm-1 is observed in HREELS, compared with 766â cm-1 calculated by DFT. The calculations also predict that the Ce=O bond is weak, with an oxygen vacancy formation energy of 0.85â eV. This could play an important role in the facile removal of lattice oxygen from CeO2 , accompanied by the reduction of CeIV to CeIII , which is a key attribute of ceria-based systems in connection with their unique catalytic properties.
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A novel method of measuring the core level binding energies of multiple sized nanoparticles on the same substrate is demonstrated using the early stage of Au nanoparticle growth on reduced r-TiO2(110). This method employed in situ scanning tunneling microscopy (STM) and microfocused X-ray photoemission spectroscopy. An STM tip-shadowing method was used to synthesize patterned areas of Au nanoparticles on the substrate with different coverages and sizes. Patterns were identified and imaged using a UV photoelectron emission microscope. The Au 4f core level binding energies of the nanoparticles were investigated as a function of Au nanoparticle coverage and size. A combination of initial and final state effects modifies the binding energies of the Au 4f core levels as the nanoparticle size changes. When single Au atoms and Au3 clusters are present, the Au 4f7/2 binding energy, 84.42 eV, is similar to that observed at a high coverage (1.8 monolayer equivalent), resulting from a cancellation of initial and final state effects. As the coverage is increased, there is a decrease in binding energy, which then increases at a higher coverage to 84.39 eV. These results are consistent with a Volmer-Weber nucleation-growth model of Au nanoparticles at oxygen vacancies, resulting in electron transfer to the nanoparticles.
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BACKGROUND: The Institute of Medicine reported that more than 1.5 million preventable adverse drug events occur annually in the United States. Comprehensive Medication Management (CMM) is the medication review process to improve clinical outcomes, enhance patient adherence, reduce drug therapy problems and reduce health care costs. University of Texas (UT) Physicians implemented a CMM program in several community-based clinics. We evaluated the effectiveness of CMM to reduce drug therapy problems and achieve medical cost savings. METHODS: This was a retrospective, observational study of CMM participants from October 2015 to September 2016. Program participants included patients aged 18 years or older who had taken more than 4 prescribed medications and were diagnosed with at least one of the following chronic diseases: hypertension, congestive heart failure, chronic obstructive pulmonary disease, asthma or diabetes. Under the CMM program, a clinical pharmacist reviewed patients' electronic health records and created action plans to resolve identified drug problems. As part of the evaluation of the clinical process, two independent physicians conducted peer review on the recommendations issued by the pharmacist in order to establish inter-rater reliability of drug therapy problems and potential consequent medical services. The drug therapy problems were identified and classified into four categories: indication, effectiveness, safety and/or compliance. The average cost of avoided medical services was obtained based on cost extrapolations from the literature, combined with hospital discharge data. Potential medical services avoided were linked to the average cost of those services to calculate the total cost savings of the program from the payers' perspective. RESULTS: By reviewing electronic health records of 3280 patients, the pharmacist identified 301 drug therapy problems and resolved 49.8% of these problems with collaboration from the patient's primary care physician or care team. The most commonly identified drug problems were related to potentially adverse drug reactions or inappropriate drug dosage. The CMM program resulted in potential cost savings of $1,143,015. CONCLUSIONS: The CMM program resolved medication therapy problems among program participants and achieved significant health care cost savings.
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Enfermedad Crónica/tratamiento farmacológico , Administración del Tratamiento Farmacológico/organización & administración , Atención Primaria de Salud/organización & administración , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Reforma de la Atención de Salud , Investigación sobre Servicios de Salud , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Programas y Proyectos de Salud , Reembolso de Incentivo/organización & administración , Estudios Retrospectivos , Texas , Adulto JovenRESUMEN
AIM: To investigate whether the timing of root canal treatment (primary aim) or other endodontic parameters (secondary aim) is associated with the survival probability of autotransplanted third molars, using a nationwide population-based database. METHODOLOGY: A total of 1811 third molars autotransplanted between 2000 and 2013 met the inclusion criteria and were followed until the end of 2016. The teeth were classified into three groups on the basis of timing between root canal treatment and the autotransplantation: preoperative, extraoral and postoperative treatment groups. Univariate and multivariate Cox proportional hazards models were used to estimate the association between the timing of root canal treatment and the risk of tooth extraction after autotransplantation. RESULTS: Of the 1811 autotransplanted third molars, 462 were extracted, yielding a 17-year survival probability of 0.578. The survival probability of autotransplanted teeth that received postoperative root fillings after 17 years was 0.583, which was significantly higher than the 0.434 and 0.566 for teeth that received preoperative and extraoral root fillings, respectively (P = 0.0013). After adjustment for potential confounding factors, teeth that received postoperative root fillings were associated with a significantly lower tooth extraction hazard ratio (HR) compared with those that received extraoral root fillings (adjusted HR, 1.43; 95% confidence interval [CI], 1.14-1.78) and those that received preoperative root fillings (adjusted HR, 2.13; 95% CI, 1.19-3.82). Furthermore, the use of a rubber dam during postoperative root filling was associated with a significantly lower extraction rate after autotransplantation (adjusted HR, 0.54; 95% CI, 0.43-0.69). CONCLUSIONS: Postoperative root canal treatment resulted in a significantly lower extraction rate than did preoperative or extraoral root canal treatment amongst autotransplanted third molars during a mean follow-up period of 8.33 years. Rubber dam use is recommended during postoperative root canal treatment to improve the outcomes of autotransplantation.
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Tercer Molar , Tratamiento del Conducto Radicular , Estudios de Seguimiento , Tasa de Supervivencia , Trasplante Autólogo , Resultado del TratamientoRESUMEN
BACKGROUND: Traumatic Brain Injury (TBI) is a leading cause of fatality and disability worldwide, partly due to the occurrence of secondary injury and late interventions. Correct diagnosis and timely monitoring ensure effective medical intervention aimed at improving clinical outcome. However, due to the limitations in size and cost of current ambulatory bioinstruments, they cannot be used to monitor patients who may still be at risk of secondary injury outside the ICU. METHODS: We propose a complete system consisting of a wearable wireless bioinstrument and a cloud-based application for real-time TBI monitoring. The bioinstrument can simultaneously record up to ten channels including both ECoG biopotential and neurochemicals (e.g. potassium, glucose and lactate), and supports various electrochemical methods including potentiometry, amperometry and cyclic voltammetry. All channels support variable gain programming to automatically tune the input dynamic range and address biosensors' falling sensitivity. The instrument is flexible and can be folded to occupy a small space behind the ear. A Bluetooth Low-Energy (BLE) receiver is used to wirelessly connect the instrument to a cloud application where the recorded data is stored, processed and visualised in real-time. Bench testing has been used to validate device performance. RESULTS: The instrument successfully monitored spreading depolarisations (SDs) - reproduced using a signal generator - with an SNR of 29.07 dB and NF of 0.26 dB. The potentiostat generates a wide voltage range from -1.65V to +1.65V with a resolution of 0.8mV and the sensitivity of the amperometric AFE was verified by recording 5 pA currents. Different potassium, glucose and lactate concentrations prepared in lab were accurately measured and their respective working curves were constructed. Finally,the instrument achieved a maximum sampling rate of 1.25 ksps/channel with a throughput of 105 kbps. All measurements were successfully received at the cloud. CONCLUSION: The proposed instrument uniquely positions itself by presenting an aggressive optimisation of size and cost while maintaining high measurement accuracy. The system can effectively extend neuroelectrochemical monitoring to all TBI patients including those who are mobile and those who are outside the ICU. Finally, data recorded in the cloud application could be used to help diagnosis and guide rehabilitation.