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1.
Proc Natl Acad Sci U S A ; 120(44): e2306177120, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37871210

RESUMEN

Lepidopterans affect crop production worldwide. The use of transgenes encoding insecticidal proteins from Bacillus thuringiensis (Bt) in crop plants is a well-established technology that enhances protection against lepidopteran larvae. Concern about widespread field-evolved resistance to Bt proteins has highlighted an urgent need for new insecticidal proteins with different modes or sites of action. We discovered a new family of insecticidal proteins from ferns. The prototype protein from Pteris species (Order Polypodiales) and variants from two other orders of ferns, Schizaeales and Ophioglossales, were effective against important lepidopteran pests of maize and soybean in diet-based assays. Transgenic maize and soybean plants producing these proteins were more resistant to insect damage than controls. We report here the crystal structure of a variant of the prototype protein to 1.98 Å resolution. Remarkably, despite being derived from plants, the structure resembles the 3-domain Cry proteins from Bt but has only two out of three of their characteristic domains, lacking the C-terminal domain which is typically required for their activities. Two of the fern proteins were effective against strains of fall armyworm that were resistant to Bt 3-domain Cry proteins Cry1Fa or Cry2A.127. This therefore represents a novel family of insecticidal proteins that have the potential to provide future tools for pest control.


Asunto(s)
Bacillus thuringiensis , Helechos , Insecticidas , Tracheophyta , Animales , Insecticidas/metabolismo , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Control Biológico de Vectores , Endotoxinas/genética , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Tracheophyta/metabolismo , Zea mays/metabolismo
2.
Circulation ; 147(20): 1492-1504, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-36871212

RESUMEN

BACKGROUND: Self-management education and support (SMES) interventions have modest effects on intermediate outcomes for those at risk of cardiovascular disease, but few studies have measured or demonstrated an effect on clinical end points. Advertising for commercial products is known to influence behavior, but advertising principles are not typically incorporated into SMES design. METHODS: This randomized trial studied the effect of a novel tailored SMES program designed by an advertising firm among a population of older adults with low income at high cardiovascular risk in Alberta, Canada. The intervention included health promotion messaging from a fictitious "peer" and facilitated relay of clinical information to patients' primary care provider and pharmacist. The primary outcome was the composite of death, myocardial infarction, stroke, coronary revascularization, and hospitalizations for cardiovascular-related ambulatory care-sensitive conditions. Rates of the primary outcome and its components were compared using negative binomial regression. Secondary outcomes included quality of life (EQ-5D [EuroQoL 5-dimension] index score), medication adherence, and overall health care costs. RESULTS: We randomized 4761 individuals, with a mean age of 74.4 years, of whom 46.8% were female. There was no evidence of statistical interaction (P=0.99) or of a synergistic effect between the 2 interventions in the factorial trial with respect to the primary outcome, which allowed us to evaluate the effect of each intervention separately. Over a median follow-up time of 36 months, the rate of the primary outcome was lower in the group that received SMES compared with the control group (incidence rate ratio, 0.78 [95% CI, 0.61 to 1.00]; P=0.047). No significant between-group changes in quality of life over time were observed (mean difference, 0.0001 [95% CI, -0.018 to 0.018]; P=0.99). The proportion of participants who were adherent to medications was not different between the 2 groups (P=0.199 for statins and P=0.754 for angiotensin-converting enzyme inhibitors/angiotensin receptor blockers). Overall adjusted health care costs did not differ between those receiving SMES and the control group ($2015 [95% CI, -$1953 to $5985]; P=0.320). CONCLUSIONS: For older adults with low income, a tailored SMES program using advertising principles reduced the rate of clinical outcomes compared with usual care. The mechanisms of improvement are unclear and further studies are required. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02579655.


Asunto(s)
Enfermedades Cardiovasculares , Automanejo , Humanos , Femenino , Anciano , Masculino , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Calidad de Vida , Publicidad , Factores de Riesgo , Factores de Riesgo de Enfermedad Cardiaca , Alberta
3.
Circulation ; 147(20): 1505-1514, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-36871215

RESUMEN

BACKGROUND: One in eight people with heart disease has poor medication adherence that, in part, is related to copayment costs. This study tested whether eliminating copayments for high-value medications among low-income older adults at high cardiovascular risk would improve clinical outcomes. METHODS: This randomized 2×2 factorial trial studied 2 distinct interventions in Alberta, Canada: eliminating copayments for high-value preventive medications and a self-management education and support program (reported separately). The findings for the first intervention, which waived the usual 30% copayment on 15 medication classes commonly used to reduce cardiovascular events, compared with usual copayment, is reported here. The primary outcome was the composite of death, myocardial infarction, stroke, coronary revascularization, and cardiovascular-related hospitalizations over a 3-year follow-up. Rates of the primary outcome and its components were compared using negative binomial regression. Secondary outcomes included quality of life (Euroqol 5-dimension index score), medication adherence, and overall health care costs. RESULTS: A total of 4761 individuals were randomized and followed for a median of 36 months. There was no evidence of statistical interaction (P=0.99) or of a synergistic effect between the 2 interventions in the factorial trial with respect to the primary outcome, which allowed us to evaluate the effect of each intervention separately. The rate of the primary outcome was not reduced by copayment elimination, (521 versus 533 events, incidence rate ratio 0.84 [95% CI, 0.66-1.07], P=0.162). The incidence rate ratio for nonfatal myocardial infarction, nonfatal stroke, and cardiovascular death (0.97 [95% CI, 0.67-1.39]), death (0.94 [95% CI, 0.80 to 1.11]), and cardiovascular-related hospitalizations (0.78 [95% CI, 0.57 to 1.06]) did not differ between groups. No significant between-group changes in quality of life over time were observed (mean difference, 0.012 [95% CI, -0.006 to 0.030], P=0.19). The proportion of participants who were adherent to statins was 0.72 versus 0.69 for the copayment elimination versus usual copayment groups, respectively (mean difference, 0.03 [95% CI, 0.006-0.06], P=0.016). Overall adjusted health care costs did not differ ($3575 [95% CI, -605 to 7168], P=0.098). CONCLUSIONS: In low-income adults at high cardiovascular risk, eliminating copayments (average, $35/mo) did not improve clinical outcomes or reduce health care costs, despite a modest improvement in adherence to medications. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02579655.


Asunto(s)
Enfermedades Cardiovasculares , Infarto del Miocardio , Accidente Cerebrovascular , Humanos , Anciano , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Calidad de Vida , Factores de Riesgo , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/epidemiología , Infarto del Miocardio/prevención & control , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/prevención & control , Alberta
4.
Circulation ; 147(22): 1670-1683, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37039015

RESUMEN

BACKGROUND: ET-1 (endothelin-1) is implicated in the pathophysiology of heart failure and renal disease. Its prognostic importance and relationship with kidney function in patients with heart failure with reduced ejection fraction receiving contemporary treatment are uncertain. We investigated these and the efficacy of dapagliflozin according to ET-1 level in the DAPA-HF trial (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure). METHODS: We investigated the incidence of the primary outcome (cardiovascular death or worsening heart failure), change in kidney function, and the effect of dapagliflozin according to baseline ET-1 concentration, adjusting in Cox models for other recognized prognostic variables in heart failure including NT-proBNP (N-terminal pro-B-type natriuretic peptide). We also examined the effect of dapagliflozin on ET-1 level. RESULTS: Overall, 3048 participants had baseline ET-1 measurements: tertile 1 (T1; ≤3.28 pg/mL; n=1016); T2 (>3.28-4.41 pg/mL; n=1022); and T3 (>4.41 pg/mL; n=1010). Patients with higher ET-1 were more likely male, more likely obese, and had lower left ventricular ejection fraction, lower estimated glomerular filtration rate, worse functional status, and higher NT-proBNP and hs-TnT (high-sensitivity troponin-T). In the adjusted Cox models, higher baseline ET-1 was independently associated with worse outcomes and steeper decline in kidney function (adjusted hazard ratio for primary outcome of 1.95 [95% CI, 1.53-2.50] for T3 and 1.36 [95% CI, 1.06-1.75] for T2; both versus T1; estimated glomerular filtration rate slope: T3, -3.19 [95% CI, -3.66 to -2.72] mL/min per 1.73 m2 per y, T2, -2.08 [95% CI, -2.52 to -1.63] and T1 -2.35 [95% CI, -2.79 to -1.91]; P=0.002). The benefit of dapagliflozin was consistent regardless of baseline ET-1, and the placebo-corrected decrease in ET-1 with dapagliflozin was 0.13 pg/mL (95% CI, 0.25-0.01; P=0.029). CONCLUSIONS: Higher baseline ET-1 concentration was independently associated with worse clinical outcomes and more rapid decline in kidney function. The benefit of dapagliflozin was consistent across the range of ET-1 concentrations measured, and treatment with dapagliflozin led to a small decrease in serum ET-1 concentration. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03036124.


Asunto(s)
Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Humanos , Masculino , Volumen Sistólico , Función Ventricular Izquierda , Endotelina-1/farmacología , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/complicaciones , Disfunción Ventricular Izquierda/tratamiento farmacológico , Compuestos de Bencidrilo/efectos adversos
5.
J Am Chem Soc ; 146(26): 18161-18171, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38916483

RESUMEN

Inorganic ternary metal-C-N compounds with covalently bonded C-N anions encompass important classes of solids such as cyanides and carbodiimides, well known at ambient conditions and composed of [CN]- and [CN2]2- anions, as well as the high-pressure formed guanidinates featuring [CN3]5- anion. At still higher pressures, carbon is expected to be 4-fold coordinated by nitrogen atoms, but hitherto, such CN4-built anions are missing. In this study, four polycarbonitride compounds (LaCN3, TbCN3, CeCN5, and TbCN5) are synthesized in laser-heated diamond anvil cells at pressures between 90 and 111 GPa. Synchrotron single-crystal X-ray diffraction (SCXRD) reveals that their crystal structures are built of a previously unobserved anionic single-bonded carbon-nitrogen three-dimensional (3D) framework consisting of CN4 tetrahedra connected via di- or oligo-nitrogen linkers. A crystal-chemical analysis demonstrates that these polycarbonitride compounds have similarities to lanthanide silicon phosphides. Decompression experiments reveal the existence of LaCN3 and CeCN5 compounds over a very large pressure range. Density functional theory (DFT) supports these discoveries and provides further insight into the stability and physical properties of the synthesized compounds.

6.
Mod Pathol ; 37(4): 100447, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38369187

RESUMEN

Pathologists have, over several decades, developed criteria for diagnosing and grading prostate cancer. However, this knowledge has not, so far, been included in the design of convolutional neural networks (CNN) for prostate cancer detection and grading. Further, it is not known whether the features learned by machine-learning algorithms coincide with diagnostic features used by pathologists. We propose a framework that enforces algorithms to learn the cellular and subcellular differences between benign and cancerous prostate glands in digital slides from hematoxylin and eosin-stained tissue sections. After accurate gland segmentation and exclusion of the stroma, the central component of the pipeline, named HistoEM, utilizes a histogram embedding of features from the latent space of the CNN encoder. Each gland is represented by 128 feature-wise histograms that provide the input into a second network for benign vs cancer classification of the whole gland. Cancer glands are further processed by a U-Net structured network to separate low-grade from high-grade cancer. Our model demonstrates similar performance compared with other state-of-the-art prostate cancer grading models with gland-level resolution. To understand the features learned by HistoEM, we first rank features based on the distance between benign and cancer histograms and visualize the tissue origins of the 2 most important features. A heatmap of pixel activation by each feature is generated using Grad-CAM and overlaid on nuclear segmentation outlines. We conclude that HistoEM, similar to pathologists, uses nuclear features for the detection of prostate cancer. Altogether, this novel approach can be broadly deployed to visualize computer-learned features in histopathology images.


Asunto(s)
Patólogos , Neoplasias de la Próstata , Masculino , Humanos , Flujo de Trabajo , Redes Neurales de la Computación , Algoritmos , Neoplasias de la Próstata/patología
7.
Eur Heart J ; 44(31): 2966-2977, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37210742

RESUMEN

BACKGROUND AND AIMS: To examine the decongestive effect of the sodium-glucose cotransporter 2 inhibitor dapagliflozin compared to the thiazide-like diuretic metolazone in patients hospitalized for heart failure and resistant to treatment with intravenous furosemide. METHODS AND RESULTS: A multi-centre, open-label, randomized, and active-comparator trial. Patients were randomized to dapagliflozin 10 mg once daily or metolazone 5-10 mg once daily for a 3-day treatment period, with follow-up for primary and secondary endpoints until day 5 (96 h). The primary endpoint was a diuretic effect, assessed by change in weight (kg). Secondary endpoints included a change in pulmonary congestion (lung ultrasound), loop diuretic efficiency (weight change per 40 mg of furosemide), and a volume assessment score. 61 patients were randomized. The mean (±standard deviation) cumulative dose of furosemide at 96 h was 977 (±492) mg in the dapagliflozin group and 704 (±428) mg in patients assigned to metolazone. The mean (±standard deviation) decrease in weight at 96 h was 3.0 (2.5) kg with dapagliflozin compared to 3.6 (2.0) kg with metolazone [mean difference 0.65, 95% confidence interval (CI) -0.12,1.41 kg; P = 0.11]. Loop diuretic efficiency was less with dapagliflozin than with metolazone [mean 0.15 (0.12) vs. 0.25 (0.19); difference -0.08, 95% CI -0.17,0.01 kg; P = 0.10]. Changes in pulmonary congestion and volume assessment score were similar between treatments. Decreases in plasma sodium and potassium and increases in urea and creatinine were smaller with dapagliflozin than with metolazone. Serious adverse events were similar between treatments. CONCLUSION: In patients with heart failure and loop diuretic resistance, dapagliflozin was not more effective at relieving congestion than metolazone. Patients assigned to dapagliflozin received a larger cumulative dose of furosemide but experienced less biochemical upset than those assigned to metolazone. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04860011.


Asunto(s)
Insuficiencia Cardíaca , Metolazona , Humanos , Metolazona/uso terapéutico , Metolazona/efectos adversos , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/uso terapéutico , Furosemida/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/inducido químicamente , Diuréticos/uso terapéutico , Sodio
8.
J Am Chem Soc ; 145(25): 13570-13580, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37318835

RESUMEN

Holliday 4-way junctions are key to important biological DNA processes (insertion, recombination, and repair) and are dynamic structures that adopt either open or closed conformations, the open conformation being the biologically active form. Tetracationic metallo-supramolecular pillarplexes display aryl faces about a cylindrical core, an ideal structure to interact with open DNA junction cavities. Combining experimental studies and MD simulations, we show that an Au pillarplex can bind DNA 4-way (Holliday) junctions in their open form, a binding mode not accessed by synthetic agents before. Pillarplexes can bind 3-way junctions too, but their large size leads them to open up and expand that junction, disrupting the base pairing, which manifests in an increased hydrodynamic size and lower junction thermal stability. At high loading, they rearrange both 4-way and 3-way junctions into Y-shaped forks to increase the available junction-like binding sites. Isostructural Ag pillarplexes show similar DNA junction binding behavior but lower solution stability. This pillarplex binding contrasts with (but complements) that of metallo-supramolecular cylinders, which prefer 3-way junctions and can rearrange 4-way junctions into 3-way junction structures. The pillarplexes' ability to bind open 4-way junctions creates exciting possibilities to modulate and switch such structures in biology, as well as in synthetic nucleic acid nanostructures. In human cells, the pillarplexes do reach the nucleus, with antiproliferative activity at levels similar to those of cisplatin. The findings provide a new roadmap for targeting higher-order junction structures using a metallo-supramolecular approach, as well as expanding the toolbox available to design bioactive junction binders into organometallic chemistry.


Asunto(s)
ADN Cruciforme , Ácidos Nucleicos , Humanos , Conformación de Ácido Nucleico , ADN/química , Sitios de Unión
9.
J Cell Sci ; 134(21)2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34622919

RESUMEN

Some organelles cannot be synthesized anew, so they are segregated into daughter cells during cell division. In Saccharomyces cerevisiae, daughter cells bud from mother cells and are populated by organelles inherited from the mothers. To determine whether this organelle inheritance occurs in a stereotyped manner, we tracked organelles using fluorescence microscopy. We describe a program for organelle inheritance in budding yeast. The cortical endoplasmic reticulum (ER) and peroxisomes are inherited concomitantly with bud emergence. Next, vacuoles are inherited in small buds, followed closely by mitochondria. Finally, the nucleus and perinuclear ER are inherited when buds have nearly reached their maximal size. Because organelle inheritance timing correlates with bud morphology, which is coupled to the cell cycle, we tested whether disrupting the cell cycle alters organelle inheritance order. By arresting cell cycle progression but allowing continued bud growth, we determined that organelle inheritance still occurs when DNA replication is blocked, and that the general inheritance order is maintained. Thus, organelle inheritance follows a preferred order during polarized cell division and does not require completion of S-phase.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Ciclo Celular/genética , División Celular/genética , Peroxisomas/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
10.
Am J Kidney Dis ; 81(5): 564-574, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36470530

RESUMEN

RATIONALE & OBJECTIVE: Sick day medication guidance (SDMG) involves withholding or adjusting specific medications in the setting of acute illnesses that could contribute to complications such as hypotension, acute kidney injury (AKI), or hypoglycemia. We sought to achieve consensus among clinical experts on recommendations for SDMG that could be studied in future intervention studies. STUDY DESIGN: A modified Delphi process following guidelines for conducting and reporting Delphi studies. SETTING & PARTICIPANTS: An international group of clinicians with expertise relevant to SDMG was recruited through purposive and snowball sampling. A scoping review of the literature was presented, followed by 3 sequential rounds of development, refinement, and voting on recommendations. Meetings were held virtually and structured to allow the participants to provide their input and rapidly prioritize and refine ideas. OUTCOME: Opinions of participants were measured as the percentage who agreed with each recommendation, whereas consensus was defined as >75% agreement. ANALYTICAL APPROACH: Quantitative data were summarized using counts and percentages. A qualitative content analysis was performed to capture the context of the discussion around recommendations and any additional considerations brought forward by participants. RESULTS: The final panel included 26 clinician participants from 4 countries and 10 clinical disciplines. Participants reached a consensus on 42 specific recommendations: 5 regarding the signs and symptoms accompanying volume depletion that should trigger SDMG; 6 regarding signs that should prompt urgent contact with a health care provider (including a reduced level of consciousness, severe vomiting, low blood pressure, presence of ketones, tachycardia, and fever); and 14 related to scenarios and strategies for patient self-management (including frequent glucose monitoring, checking ketones, fluid intake, and consumption of food to prevent hypoglycemia). There was consensus that renin-angiotensin system inhibitors, diuretics, nonsteroidal anti-inflammatory drugs, sodium/glucose cotransporter 2 inhibitors, and metformin should be temporarily stopped. Participants recommended that insulin, sulfonylureas, and meglitinides be held only if blood glucose was low and that basal and bolus insulin be increased by 10%-20% if blood glucose was elevated. There was consensus on 6 recommendations related to the resumption of medications within 24-48 hours of the resolution of symptoms and the presence of normal patterns of eating and drinking. LIMITATIONS: Participants were from high-income countries, predominantly Canada. Findings may not be generalizable to implementation in other settings. CONCLUSIONS: A multidisciplinary panel of clinicians reached a consensus on recommendations for SDMG in the presence of signs and symptoms of volume depletion, as well as self-management strategies and medication instructions in this setting. These recommendations may inform the design of future trials of SDMG strategies.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus , Hipoglucemia , Insulinas , Humanos , Enfermedades Cardiovasculares/tratamiento farmacológico , Glucemia , Consenso , Automonitorización de la Glucosa Sanguínea , Ausencia por Enfermedad , Diabetes Mellitus/tratamiento farmacológico , Hipoglucemia/inducido químicamente , Hipoglucemia/prevención & control , Hipovolemia , Riñón , Técnica Delphi
11.
Opt Express ; 31(13): 20651-20664, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37381184

RESUMEN

Persistent wideband radio frequency (RF) surveillance and spectral analysis is increasingly important, driven by the proliferation of wireless communication and RADAR technology. However, conventional electronic approaches are limited by the ∼1 GHz bandwidth of real-time analog-to-digital converters (ADCs). While faster ADCs exist, high data rates prohibit continuous operation, limiting these approaches to acquiring short snapshots of the RF spectrum. In this work, we introduce an optical RF spectrum analyzer designed for continuous, wideband operation. Our approach encodes the RF spectrum as sidebands on an optical carrier and relies on a speckle spectrometer to measure these sidebands. To achieve the resolution and update rate required for RF analysis, we use Rayleigh backscattering in single-mode fiber to rapidly generate wavelength-dependent speckle patterns with MHz-level spectral correlation. We also introduce a dual-resolution scheme to mitigate the trade-off between resolution, bandwidth, and measurement rate. This optimized spectrometer design enables continuous, wideband (15 GHz) RF spectral analysis with MHz-level resolution and a fast update rate of 385 kHz. The entire system is constructed using fiber-coupled off-the-shelf-components, providing a powerful new approach for wideband RF detection and monitoring.

12.
PLoS Comput Biol ; 18(10): e1010633, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36279274

RESUMEN

Ancestral sequence reconstruction is a technique that is gaining widespread use in molecular evolution studies and protein engineering. Accurate reconstruction requires the ability to handle appropriately large numbers of sequences, as well as insertion and deletion (indel) events, but available approaches exhibit limitations. To address these limitations, we developed Graphical Representation of Ancestral Sequence Predictions (GRASP), which efficiently implements maximum likelihood methods to enable the inference of ancestors of families with more than 10,000 members. GRASP implements partial order graphs (POGs) to represent and infer insertion and deletion events across ancestors, enabling the identification of building blocks for protein engineering. To validate the capacity to engineer novel proteins from realistic data, we predicted ancestor sequences across three distinct enzyme families: glucose-methanol-choline (GMC) oxidoreductases, cytochromes P450, and dihydroxy/sugar acid dehydratases (DHAD). All tested ancestors demonstrated enzymatic activity. Our study demonstrates the ability of GRASP (1) to support large data sets over 10,000 sequences and (2) to employ insertions and deletions to identify building blocks for engineering biologically active ancestors, by exploring variation over evolutionary time.


Asunto(s)
Evolución Molecular , Mutación INDEL , Mutación INDEL/genética , Proteínas/genética , Evolución Biológica , Filogenia
13.
Cerebrovasc Dis ; 52(2): 123-129, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36037797

RESUMEN

Cardiac rhythm monitoring is performed to search for atrial fibrillation (AF) after ischaemic stroke or transient ischaemic attack (TIA). Prolonged cardiac rhythm monitoring increases AF detection but is challenging to implement in many healthcare settings and is not needed for all people after ischaemic stroke/TIA. We aimed to develop and validate a model that includes clinical, electrocardiogram (ECG), blood-based, and genetic biomarkers to identify people with a low probability of AF detection after ischaemic stroke or TIA. We will recruit 675 consenting participants who are aged over 18 years, who were admitted with ischaemic stroke or TIA in the 5 days prior, who are not known to have AF, and who would be suitable for anticoagulation if AF is found. We will collect baseline demographic and clinical data, a 12-lead ECG, and a venous blood sample for blood biomarkers (including midregional pro-atrial natriuretic peptide, MRproANP) and genetic data. We will perform up to 28 days of cardiac rhythm monitoring using an R-test or patch device to search for AF in all participants. The sample size of 675 participants is based on true sensitivity of 92.5%, null hypothesis sensitivity of 80%, 80% power, and 5% significance. The primary outcome is AF detection ≥30 s duration during 28 days of cardiac rhythm monitoring. Secondary outcomes are AF detection at 1-year, recurrent cardiovascular events, and mortality and will be identified by electronic linkage and telephone follow-up. The results will guide the development of a more personalized care pathway to search for AF after ischaemic stroke or TIA. This could help to reduce cardiac rhythm monitoring for people with a low probability of AF detection and allow more intensive cardiac monitoring to be focused on people who are more likely to have AF and benefit. Participants will be consented for their data to be used in future research studies, providing a rich resource for stroke and cardiovascular research communities.


Asunto(s)
Fibrilación Atrial , Isquemia Encefálica , Accidente Cerebrovascular Embólico , Ataque Isquémico Transitorio , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Adulto , Persona de Mediana Edad , Accidente Cerebrovascular/diagnóstico , Ataque Isquémico Transitorio/diagnóstico , Isquemia Encefálica/diagnóstico , Fibrilación Atrial/diagnóstico , Accidente Cerebrovascular Isquémico/complicaciones
14.
BMC Neurol ; 23(1): 53, 2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36732694

RESUMEN

BACKGROUND: Multiple sclerosis (MS) is a chronic disease affecting multiple functional aspects of patients' lives. Depression and anxiety are common amongst persons with MS (PwMS). There has been an interest in utilizing patient-reported outcome measures (PROMs) to capture and systematically assess patient's perceptions of their MS experience in addition to other clinical measures, but PROMs are not usually collected in routine clinical practice. Therefore, this study aims to systematically incorporate periodic electronically administered PROMs into the care of PwMS to evaluate its effects on depression and anxiety. METHODS: A randomized controlled trial will be conducted with patients allocated 1:1 to either intervention or conservative treatment groups. Patients in the intervention group will complete PROMs at the start of the study and then every 6 months for 1 year, in addition to having their MS healthcare provider prompted to view their scores. The conservative treatment group will complete PROMs at the start of the study and again after 12 months, and their neurologist will not be able to view their scores. For both groups, pre-determined critical PROM scores will trigger an alert to the patient's MS provider. The difference in change in Hospital Anxiety and Depression Scale score between the intervention and conservative treatment groups at 12 months will be the primary outcome, along with difference in Consultation Satisfaction Questionnaire and CollaboRATE scores at 12 months, and proportion and type of healthcare provider intervention/alerts initiated by different PROMs as secondary outcomes. DISCUSSION: This study will determine the feasibility of utilizing PROMs on an interval basis and its effects on the psychological well-being of PwMS. Findings of this study will provide evidence on use of PROMs in future MS clinical practice. TRIAL REGISTRATION: This trial is registered at the National Institutes of Health United States National Library of Medicine, ClinicalTrials.gov NCT04979546 . Registered on July 28, 2021.


Asunto(s)
Esclerosis Múltiple , Humanos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/psicología , Depresión/epidemiología , Depresión/etiología , Depresión/terapia , Ansiedad/terapia , Trastornos de Ansiedad , Medición de Resultados Informados por el Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto
15.
Pediatr Nephrol ; 38(5): 1667-1685, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36260162

RESUMEN

BACKGROUND: Few studies describe acute kidney injury (AKI) burden during paediatric cisplatin therapy and post-cisplatin kidney outcomes. We determined risk factors for and rate of (1) AKI during cisplatin therapy, (2) chronic kidney disease (CKD) and hypertension 2-6 months post-cisplatin, and (3) whether AKI is associated with 2-6-month outcomes. METHODS: This prospective cohort study enrolled children (aged < 18 years at cancer diagnosis) treated with cisplatin from twelve Canadian hospitals. AKI during cisplatin therapy (primary exposure) was defined based on Kidney Disease: Improving Global Outcomes (KDIGO) serum creatinine criteria (≥ stage one). Severe electrolyte abnormalities (secondary exposure) included ≥ grade three hypophosphatemia, hypokalemia, or hypomagnesemia (National Cancer Institute Common Terminology Criteria for Adverse Events v4.0). CKD was albuminuria or decreased kidney function for age (KDIGO guidelines). Hypertension was defined based on the 2017 American Academy of Pediatrics guidelines. RESULTS: Of 159 children (median [interquartile range [IQR]] age: 6 [2-12] years), 73/159 (46%) participants developed AKI and 55/159 (35%) experienced severe electrolyte abnormalities during cisplatin therapy. At median [IQR] 90 [76-110] days post-cisplatin, 53/119 (45%) had CKD and 18/128 (14%) developed hypertension. In multivariable analyses, AKI was not associated with 2-6-month CKD or hypertension. Severe electrolyte abnormalities during cisplatin were associated with having 2-6-month CKD or hypertension (adjusted odds ratio (AdjOR) [95% CI]: 2.65 [1.04-6.74]). Having both AKI and severe electrolyte abnormalities was associated with 2-6-month hypertension (AdjOR [95% CI]: 3.64 [1.05-12.62]). CONCLUSIONS: Severe electrolyte abnormalities were associated with kidney outcomes. Cisplatin dose optimization to reduce toxicity and clear post-cisplatin kidney follow-up guidelines are needed. A higher resolution version of the Graphical abstract is available as Supplementary information.


Asunto(s)
Lesión Renal Aguda , Hipertensión , Insuficiencia Renal Crónica , Humanos , Niño , Preescolar , Cisplatino/efectos adversos , Estudios Prospectivos , Estudios Retrospectivos , Canadá , Riñón , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/diagnóstico , Insuficiencia Renal Crónica/complicaciones , Hipertensión/tratamiento farmacológico , Factores de Riesgo , Electrólitos
16.
Can J Neurol Sci ; : 1-9, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37994530

RESUMEN

INTRODUCTION: Despite the importance of timing of nerve surgery after peripheral nerve injury, optimal timing of intervention has not been clearly delineated. The goal of this study is to explore factors that may have a significant impact on clinical outcomes of severe peripheral nerve injury that requires reconstruction with nerve transfer or graft. MATERIALS AND METHODS: Adult patients who underwent peripheral nerve transfer or grafting in Alberta were reviewed. Clustered multivariable logistic regression analysis was used to examine the association of time to surgery, type of nerve repair, and patient characteristics on strength outcomes. Cox proportional hazard regression analysis model was used to examine factors correlated with increased time to surgery. RESULTS: Of the 163 patients identified, the median time to surgery was 212 days. For every week of delay, the adjusted odds of achieving Medical Research Council strength grade ≥ 3 decreases by 3%. An increase in preinjury comorbidities was associated with longer overall time to surgery (aHR 0.84, 95% CI 0.74-0.95). Referrals made by surgeons were associated with a shorter time to surgery compared to general practitioners (aHR 1.87, 95% CI 1.14-3.06). In patients treated with nerve transfer, the adjusted odds of achieving antigravity strength was 388% compared to nerve grafting; while the adjusted odds decreased by 65% if the injury sustained had a pre-ganglionic injury component. CONCLUSION: Mitigating delays in surgical intervention is crucial to optimizing outcomes. The nature of initial nerve injury and surgical reconstructive techniques are additional important factors that impact postoperative outcomes.

17.
J Chem Phys ; 159(13)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37795788

RESUMEN

The binary Xe-Ar system has been studied in a series of high pressure diamond anvil cell experiments up to 60 GPa at 300 K. In-situ x-ray powder diffraction and Raman spectroscopy indicate the formation of a van der Waals compound, XeAr2, at above 3.5 GPa. Powder x-ray diffraction analysis demonstrates that XeAr2 adopts a Laves MgZn2-type structure with space group P63/mmc and cell parameters a = 6.595 Å and c = 10.716 Å at 4 GPa. Density functional theory calculations support the structure determination, with agreement between experimental and calculated Raman spectra. Our DFT calculations suggest that XeAr2 would remain stable without a structural transformation or decomposition into elemental Xe and Ar up to at least 80 GPa.

18.
Health Expect ; 26(4): 1746-1756, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37291977

RESUMEN

INTRODUCTION: People with chronic medical conditions often take medications that improve long-term outcomes but which can be harmful during acute illness. Guidelines recommend that healthcare providers offer instructions to temporarily stop these medications when patients are sick (i.e., sick days). We describe the experiences of patients managing sick days and of healthcare providers providing sick day guidance to their patients. METHODS: We undertook a qualitative descriptive study. We purposively sampled patients and healthcare providers from across Canada. Adult patients were eligible if they took at least two medications for diabetes, heart disease, high blood pressure and/or kidney disease. Healthcare providers were eligible if they were practising in a community setting with at least 1 year of experience. Data were collected using virtual focus groups and individual phone interviews conducted in English. Team members analyzed transcripts using conventional content analysis. RESULTS: We interviewed 48 participants (20 patients and 28 healthcare providers). Most patients were between 50 and 64 years of age and identified their health status as 'good'. Most healthcare providers were between 45 and 54 years of age and the majority practised as pharmacists in urban areas. We identified three overarching themes that summarize the experiences of patients and healthcare providers, largely suggesting a broad spectrum in approaches to managing sick days: Individualized Communication, Tailored Sick Day Practices, and Variation in Knowledge of Sick Day Practices and Relevant Resources. CONCLUSION: It is important to understand the perspectives of both patients and healthcare providers with respect to the management of sick days. This understanding can be used to improve care and outcomes for people living with chronic conditions during sick days. PATIENT OR PUBLIC CONTRIBUTION: Two patient partners were involved from proposal development to the dissemination of our findings, including manuscript development. Both patient partners took part in team meetings and contributed to team decision-making. Patient partners also participated in data analysis by reviewing codes and theme development. Furthermore, patients living with various chronic conditions and healthcare providers participated in focus groups and individual interviews.


Asunto(s)
Personal de Salud , Ausencia por Enfermedad , Adulto , Humanos , Investigación Cualitativa , Farmacéuticos , Enfermedad Crónica
19.
Proc Natl Acad Sci U S A ; 117(24): 13374-13378, 2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32482874

RESUMEN

Molecular hydrogen forms the archetypical quantum solid. Its quantum nature is revealed by behavior which is classically impossible and by very strong isotope effects. Isotope effects between [Formula: see text], [Formula: see text], and HD molecules come from mass difference and the different quantum exchange effects: fermionic [Formula: see text] molecules have antisymmetric wavefunctions, while bosonic [Formula: see text] molecules have symmetric wavefunctions, and HD molecules have no exchange symmetry. To investigate how the phase diagram depends on quantum-nuclear effects, we use high-pressure and low-temperature in situ Raman spectroscopy to map out the phase diagrams of [Formula: see text]-HD-[Formula: see text] with various isotope concentrations over a wide pressure-temperature (P-T) range. We find that mixtures of [Formula: see text], HD, and [Formula: see text] behave as an isotopic molecular alloy (ideal solution) and exhibit symmetry-breaking phase transitions between phases I and II and phase III. Surprisingly, all transitions occur at higher pressures for the alloys than either pure [Formula: see text] or [Formula: see text] This runs counter to any quantum effects based on isotope mass but can be explained by quantum trapping of high-kinetic energy states by the exchange interaction.

20.
Circulation ; 144(3): 199-209, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-33983794

RESUMEN

BACKGROUND: Patients with left ventricular (LV) systolic dysfunction after myocardial infarction are at a high risk of developing heart failure. The addition of neprilysin inhibition to renin angiotensin system inhibition may result in greater attenuation of adverse LV remodeling as a result of increased levels of substrates for neprilysin with vasodilatory, antihypertrophic, antifibrotic, and sympatholytic effects. METHODS: We performed a prospective, multicenter, randomized, double-blind, active-comparator trial comparing sacubitril/valsartan 97/103 mg twice daily with valsartan 160 mg twice daily in patients ≥3 months after myocardial infarction with a LV ejection fraction ≤40% who were taking a renin angiotensin system inhibitor (equivalent dose of ramipril ≥2.5 mg twice daily) and a ß-blocker unless contraindicated or intolerant. Patients in New York Heart Association class ≥II or with signs and symptoms of heart failure were excluded. The primary outcome was change from baseline to 52 weeks in LV end-systolic volume index measured using cardiac magnetic resonance imaging. Secondary outcomes included other magnetic resonance imaging measurements of LV remodeling, change in NT-proBNP (N-terminal pro-B-type natriuretic peptide) and high-sensitivity cardiac troponin I, and a patient global assessment of change questionnaire. RESULTS: From July 2018 to June 2019, we randomized 93 patients with the following characteristics: mean age, 60.7±10.4 years; median time from myocardial infarction, 3.6 years (interquartile range, 1.2-7.2); mean LV ejection fraction, 36.8%±7.1%; and median NT-proBNP, 230 pg/mL (interquartile range, 124-404). Sacubitril/valsartan, compared with valsartan, did not significantly reduce LV end-systolic volume index; adjusted between-group difference, -1.9 mL/m2 (95% CI, -4.9 to 1.0); P=0.19. There were no significant between-group differences in NT-proBNP, high-sensitivity cardiac troponin I, LV end-diastolic volume index, left atrial volume index, LV ejection fraction, LV mass index, or patient global assessment of change. CONCLUSIONS: In patients with asymptomatic LV systolic dysfunction late after myocardial infarction, treatment with sacubitril/valsartan did not have a significant reverse remodeling effect compared with valsartan. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03552575.


Asunto(s)
Infarto del Miocardio/complicaciones , Neprilisina/antagonistas & inhibidores , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/etiología , Remodelación Ventricular/efectos de los fármacos , Anciano , Aminobutiratos/administración & dosificación , Enfermedades Asintomáticas , Biomarcadores , Compuestos de Bifenilo/administración & dosificación , Susceptibilidad a Enfermedades , Combinación de Medicamentos , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Volumen Sistólico/efectos de los fármacos , Resultado del Tratamiento , Valsartán/administración & dosificación , Disfunción Ventricular Izquierda/tratamiento farmacológico
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