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1.
Cell ; 184(3): 561-565, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33503447

RESUMEN

Our nationwide network of BME women faculty collectively argue that racial funding disparity by the National Institutes of Health (NIH) remains the most insidious barrier to success of Black faculty in our profession. We thus refocus attention on this critical barrier and suggest solutions on how it can be dismantled.


Asunto(s)
Investigación Biomédica/economía , Negro o Afroamericano , Administración Financiera , Investigadores/economía , Humanos , National Institutes of Health (U.S.)/economía , Grupos Raciales , Estados Unidos
2.
Nucleic Acids Res ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39217472

RESUMEN

The thrombin binding aptamer (TBA) is a prototypical platform used to understand the impact of chemically-modified nucleotides on aptamer stability and target affinity. To provide structural insight into the experimentally-observed effects of modification size, location, and number on aptamer performance, long time-scale molecular dynamics (MD) simulations were performed on multiple binding orientations of TBA-thrombin complexes that contain a large, flexible tryptophan thymine derivative (T-W) or a truncated analogue (T-K). Depending on modification position, T-W alters aptamer-target binding orientations, fine-tunes aptamer-target interactions, strengthens networks of nucleic acid-protein contacts, and/or induces target conformational changes to enhance binding. The proximity and 5'-to-3' directionality of nucleic acid structural motifs also play integral roles in the behavior of the modifications. Modification size can differentially influence target binding by promoting more than one aptamer-target binding pose. Multiple modifications can synergistically strengthen aptamer-target binding by generating novel nucleic acid-protein structural motifs that are unobtainable for single modifications. By studying a diverse set of modified aptamers, our work uncovers design principles that must be considered in the future development of aptamers containing chemically-modified nucleotides for applications in medicine and biotechnology, highlighting the value of computational studies in nucleic acids research.

3.
Syst Biol ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554255

RESUMEN

Why and how organismal lineages radiate is commonly studied through either assessing abiotic factors (biogeography, geomorphological processes, climate) or biotic factors (traits, interactions). Despite increasing awareness that both abiotic and biotic processes may have important joint effects on diversification dynamics, few attempts have been made to quantify the relative importance and timing of these factors, and their potentially interlinked direct and indirect effects, on lineage diversification. We here combine assessments of historical biogeography, geomorphology, climatic niche, vegetative and floral trait evolution to test whether these factors jointly, or in isolation, explain diversification dynamics of a Neotropical plant clade (Merianieae, Melastomataceae). After estimating ancestral areas and the changes in niche and trait disparity over time, we employ Phylogenetic Path Analyses as a synthesis tool to test eleven hypotheses on the individual direct and indirect effects of these factors on diversification rates. We find strongest support for interlinked effects of colonization of the uplifting Andes during the mid-Miocene and rapid abiotic climatic niche evolution in explaining a burst in diversification rate in Merianieae. Within Andean habitats, later increases in floral disparity allowed for the exploitation of wider pollination niches (i.e., shifts from bee to vertebrate pollinators), but did not affect diversification rates. Our approach of including both vegetative and floral trait evolution, rare in assessments of plant diversification in general, highlights that the evolution of woody habit and larger flowers preceded the colonization of the Andes, but was likely critical in enabling the rapid radiation in montane environments. Overall, and in concert with the idea that ecological opportunity is a key element of evolutionary radiations, our results suggest that a combination of rapid niche evolution and trait shifts were critical for the exploitation of newly available niche space in the Andes in the mid-Miocene. Further, our results emphasize the importance of incorporating both abiotic and biotic factors into the same analytical framework if we aim to quantify the relative and interlinked effects of these processes on diversification.

4.
Semin Cancer Biol ; 94: 34-49, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37263529

RESUMEN

In the recent decades, chimeric antigen receptor (CAR) therapy signaled a new revolutionary approach to cancer treatment. This method seeks to engineer immune cells expressing an artificially designed receptor, which would endue those cells with the ability to recognize and eliminate tumor cells. While some CAR therapies received FDA approval and others are subject to clinical trials, many aspects of their workings remain elusive. Techniques of systems and computational biology have been frequently employed to explain the operating principles of CAR therapy and suggest further design improvements. In this review, we sought to provide a comprehensive account of those efforts. Specifically, we discuss various computational models of CAR therapy ranging in scale from organismal to molecular. Then, we describe the molecular and functional properties of costimulatory domains frequently incorporated in CAR structure. Finally, we describe the signaling cascades by which those costimulatory domains elicit cellular response against the target. We hope that this comprehensive summary of computational and experimental studies will further motivate the use of systems approaches in advancing CAR therapy.


Asunto(s)
Receptores de Antígenos de Linfocitos T , Linfocitos T , Humanos , Receptores de Antígenos de Linfocitos T/genética , Inmunoterapia Adoptiva , Transducción de Señal
5.
J Bacteriol ; 206(8): e0015024, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39057917

RESUMEN

Coxiella burnetii is a highly infectious, Gram-negative, obligate intracellular bacterium and the causative agent of human Q fever. The Coxiella Containing Vacuole (CCV) is a modified phagolysosome that forms through fusion with host endosomes and lysosomes. While an initial acidic pH < 4.7 is essential to activate Coxiella metabolism, the mature, growth-permissive CCV has a luminal pH of ~5.2 that remains stable throughout infection. Inducing CCV acidification to a lysosomal pH (~4.7) causes Coxiella degradation, suggesting that Coxiella regulates CCV pH. Supporting this hypothesis, Coxiella blocks host lysosomal biogenesis, leading to fewer host lysosomes available to fuse with the CCV. Host cell lysosome biogenesis is primarily controlled by the transcription factor EB (TFEB), which binds Coordinated Lysosomal Expression And Regulation (CLEAR) motifs upstream of genes involved in lysosomal biogenesis and function. TFEB is a member of the microphthalmia/transcription factor E (MiT/TFE) protein family, which also includes MITF, TFE3, and TFEC. This study examines the roles of MiT/TFE proteins during Coxiella infection. We found that in cells lacking TFEB, both Coxiella growth and CCV size increase. Conversely, TFEB overexpression or expression in the absence of other family members leads to significantly less bacterial growth and smaller CCVs. TFE3 and MITF do not appear to play a significant role during Coxiella infection. Surprisingly, we found that Coxiella actively blocks TFEB nuclear translocation in a Type IV Secretion System-dependent manner, thus decreasing lysosomal biogenesis. Together, these results suggest that Coxiella inhibits TFEB nuclear translocation to limit lysosomal biogenesis, thus avoiding further CCV acidification through CCV-lysosomal fusion. IMPORTANCE: The obligate intracellular bacterial pathogen Coxiella burnetii causes the zoonotic disease Q fever, which is characterized by a debilitating flu-like illness in acute cases and life-threatening endocarditis in patients with chronic disease. While Coxiella survives in a unique lysosome-like vacuole called the Coxiella Containing Vacuole (CCV), the bacterium inhibits lysosome biogenesis as a mechanism to avoid increased CCV acidification. Our results establish that transcription factor EB (TFEB), a member of the microphthalmia/transcription factor E (MiT/TFE) family of transcription factors that regulate lysosomal gene expression, restricts Coxiella infection. Surprisingly, Coxiella blocks TFEB translocation from the cytoplasm to the nucleus, thus downregulating the expression of lysosomal genes. These findings reveal a novel bacterial mechanism to regulate lysosomal biogenesis.


Asunto(s)
Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Coxiella burnetii , Lisosomas , Fiebre Q , Coxiella burnetii/genética , Coxiella burnetii/metabolismo , Coxiella burnetii/fisiología , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Lisosomas/metabolismo , Humanos , Fiebre Q/microbiología , Animales , Vacuolas/metabolismo , Vacuolas/microbiología , Ratones , Núcleo Celular/metabolismo , Transporte de Proteínas
6.
BMC Bioinformatics ; 25(1): 45, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287239

RESUMEN

BACKGROUND: Microbial communities play a crucial role in ecosystem function through metabolic interactions. Genome-scale modeling is a promising method to understand these interactions and identify strategies to optimize the community. Flux balance analysis (FBA) is most often used to predict the flux through all reactions in a genome-scale model; however, the fluxes predicted by FBA depend on a user-defined cellular objective. Flux sampling is an alternative to FBA, as it provides the range of fluxes possible within a microbial community. Furthermore, flux sampling can capture additional heterogeneity across a population, especially when cells exhibit sub-maximal growth rates. RESULTS: In this study, we simulate the metabolism of microbial communities and compare the metabolic characteristics found with FBA and flux sampling. With sampling, we find significant differences in the predicted metabolism, including an increase in cooperative interactions and pathway-specific changes in predicted flux. CONCLUSIONS: Our results suggest the importance of sampling-based approaches to evaluate metabolic interactions. Furthermore, we emphasize the utility of flux sampling in quantitatively studying interactions between cells and organisms.


Asunto(s)
Genoma , Microbiota , Redes y Vías Metabólicas/genética , Modelos Biológicos , Análisis de Flujos Metabólicos/métodos
7.
J Am Chem Soc ; 146(15): 10381-10392, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38573229

RESUMEN

DNA cross-links severely challenge replication and transcription in cells, promoting senescence and cell death. In this paper, we report a novel type of DNA interstrand cross-link (ICL) produced as a side product during the attempted repair of 1,N6-ethenoadenine (εA) by human α-ketoglutarate/Fe(II)-dependent enzyme ALKBH2. This stable/nonreversible ICL was characterized by denaturing polyacrylamide gel electrophoresis analysis and quantified by high-resolution LC-MS in well-matched and mismatched DNA duplexes, yielding 5.7% as the highest level for cross-link formation. The binary lesion is proposed to be generated through covalent bond formation between the epoxide intermediate of εA repair and the exocyclic N6-amino group of adenine or the N4-amino group of cytosine residues in the complementary strand under physiological conditions. The cross-links occur in diverse sequence contexts, and molecular dynamics simulations rationalize the context specificity of cross-link formation. In addition, the cross-link generated from attempted εA repair was detected in cells by highly sensitive LC-MS techniques, giving biological relevance to the cross-link adducts. Overall, a combination of biochemical, computational, and mass spectrometric methods was used to discover and characterize this new type of stable cross-link both in vitro and in human cells, thereby uniquely demonstrating the existence of a potentially harmful ICL during DNA repair by human ALKBH2.


Asunto(s)
Adenina/análogos & derivados , Dioxigenasas , Ácidos Cetoglutáricos , Humanos , Dioxigenasas/metabolismo , ADN/química , Reparación del ADN , Compuestos Ferrosos , Aductos de ADN , Dioxigenasa Dependiente de Alfa-Cetoglutarato, Homólogo 2 de AlkB/metabolismo
8.
Mol Phylogenet Evol ; 198: 108136, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38909873

RESUMEN

Despite the overarching history of species divergence, phylogenetic studies often reveal distinct topologies across regions of the genome. The sources of these gene tree discordances are variable, but incomplete lineage sorting (ILS) and hybridization are among those with the most biological importance. Petunia serves as a classic system for studying hybridization in the wild. While field studies suggest that hybridization is frequent, the extent of reticulation within Petunia and its closely related genera has never been examined from a phylogenetic perspective. In this study, we used transcriptomic data from 11 Petunia, 16 Calibrachoa, and 10 Fabiana species to illuminate the relationships between these species and investigate whether hybridization played a significant role in the diversification of the clade. We inferred that gene tree discordance within genera is linked to hybridization events along with high levels of ILS due to their rapid diversification. Moreover, network analyses estimated deeper hybridization events between Petunia and Calibrachoa, genera that have different chromosome numbers. Although these genera cannot hybridize at the present time, ancestral hybridization could have played a role in their parallel radiations, as they share the same habitat and life history.


Asunto(s)
Hibridación Genética , Petunia , Filogenia , Petunia/genética , Petunia/clasificación , Transcriptoma , Especiación Genética , Solanaceae/genética , Solanaceae/clasificación
9.
Chemistry ; : e202402749, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158976

RESUMEN

The first Lewis acid base adducts of MoF6 and an organic base have been synthesized, i.e., MoF6(NC5H5) and MoF6(NC5H5)2. These adducts are structurally characterized with X-ray crystallography, showing that both adducts adopt capped trigonal prismatic structures. The MoF6(NC5H5) and MoF6(NC5H5)2 adducts are fluxional on the NMR time scale at room temperature. Two different fluorine environments could be resolved by 19F NMR spectroscopy at -80 °C for the 1:2 adduct, MoF6(NC5H5)2, whereas MoF6(NC5H5) remains fluxional at that temperature. Density functional theory (DFT) calculations aide the assignment of the infrared and Raman spectra. Natural Bond Order and Molecular Electrostatic Potential analyses elucidate the structures and properties of the MoF6 pyridine adducts. Regions of significantly higher molecular electrostatic potential, i.e., σ-holes, in trigonal prismatic compared to octahedral MoF6 rationalize the capped trigonal prismatic geometry of the adducts. Whereas MoF6(NC5H5) is stable at room temperature under exclusion of moisture, MoF6(NC5H5)2 decomposes at 60 °C in pyridine solvent, and the solid slowly decomposes at room temperature after 24 h.

10.
PLoS Biol ; 19(10): e3001419, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34618807

RESUMEN

Evolving in sync with the computation revolution over the past 30 years, computational biology has emerged as a mature scientific field. While the field has made major contributions toward improving scientific knowledge and human health, individual computational biology practitioners at various institutions often languish in career development. As optimistic biologists passionate about the future of our field, we propose solutions for both eager and reluctant individual scientists, institutions, publishers, funding agencies, and educators to fully embrace computational biology. We believe that in order to pave the way for the next generation of discoveries, we need to improve recognition for computational biologists and better align pathways of career success with pathways of scientific progress. With 10 outlined steps, we call on all adjacent fields to move away from the traditional individual, single-discipline investigator research model and embrace multidisciplinary, data-driven, team science.


Asunto(s)
Biología Computacional , Presupuestos , Conducta Cooperativa , Humanos , Investigación Interdisciplinaria , Tutoría , Motivación , Publicaciones , Recompensa , Programas Informáticos
11.
J Theor Biol ; 590: 111857, 2024 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-38797470

RESUMEN

Resisting apoptosis is a hallmark of cancer. For this reason, it may be possible to force cancer cells to die by targeting components along the apoptotic signaling pathway. However, apoptosis signaling is challenging to understand due to dynamic and complex behaviors of ligands, receptors, and intracellular signaling components in response to cancer therapy. In this work, we forecast the apoptotic response based on the combined impact of these features. We expanded a previously established mathematical model of caspase-mediated apoptosis to include extracellular activation and receptor dynamics. In addition, three potential threshold values of caspase-3 necessary for the activation of apoptosis were selected to forecast which cells become apoptotic over time. We first vary ligand and receptor levels with the number of intracellular signaling proteins remaining consistent. Then, we vary the intracellular protein molecules in each simulated tumor cell to forecast the response of a heterogeneous population. By leveraging the benefits of computational modeling, we investigate the combined effect of several factors on the onset of apoptosis. This work provides quantitative insights for how the apoptotic signaling response can be forecasted, and precisely triggered, amongst heterogeneous cells via extracellular activation.


Asunto(s)
Apoptosis , Modelos Biológicos , Neoplasias , Transducción de Señal , Humanos , Neoplasias/patología , Neoplasias/metabolismo , Caspasas/metabolismo , Caspasa 3/metabolismo
12.
PLoS Comput Biol ; 19(4): e1011070, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37083821

RESUMEN

Agent-based models (ABMs) have enabled great advances in the study of tumor development and therapeutic response, allowing researchers to explore the spatiotemporal evolution of the tumor and its microenvironment. However, these models face serious drawbacks in the realm of parameterization - ABM parameters are typically set individually based on various data and literature sources, rather than through a rigorous parameter estimation approach. While ABMs can be fit to simple time-course data (such as tumor volume), that type of data loses the spatial information that is a defining feature of ABMs. While tumor images provide spatial information, it is exceedingly difficult to compare tumor images to ABM simulations beyond a qualitative visual comparison. Without a quantitative method of comparing the similarity of tumor images to ABM simulations, a rigorous parameter fitting is not possible. Here, we present a novel approach that applies neural networks to represent both tumor images and ABM simulations as low dimensional points, with the distance between points acting as a quantitative measure of difference between the two. This enables a quantitative comparison of tumor images and ABM simulations, where the distance between simulated and experimental images can be minimized using standard parameter-fitting algorithms. Here, we describe this method and present two examples to demonstrate the application of the approach to estimate parameters for two distinct ABMs. Overall, we provide a novel method to robustly estimate ABM parameters.


Asunto(s)
Algoritmos , Neoplasias , Humanos , Redes Neurales de la Computación , Neoplasias/diagnóstico por imagen , Microambiente Tumoral
13.
Inorg Chem ; 63(17): 7619-7630, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38629175

RESUMEN

Arsenic pentafluoride undergoes ligand-induced autoionization in the presence of 1,10-phenanthroline (phen) in a SO2ClF solution to form the donor-stabilized [AsF4(phen)][AsF6] salt. Reacting [AsF4(phen)][AsF6] with the strong Lewis acid SbF5·SO2 yields the mixed arsenic-antimony salt [AsF4(phen)][Sb2F11]. These salts are the first examples of crystallographically characterized donor-stabilized [AsF4]+ cations. The analogous reaction of AsF5 and 2,2'-bipyridine (bipy) does not result in autoionization but leads to the formation of the neutral 2:1 adduct (AsF5)2·bipy. The gas-phase and solution fluoride-ion affinities of [AsF4]+ and [SbF4]+ were calculated, revealing them to be incredibly strong Lewis acids. Density functional theory calculations and natural bond orbital analysis show that significant electron-pair donation from phen to the As center in [AsF4(phen)]+ occurs and quenches the extreme electrophilicity of the [AsF4]+ cation.

14.
J Chem Inf Model ; 64(3): 944-959, 2024 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-38253321

RESUMEN

Endonuclease V (EndoV) is a single-metal-dependent enzyme that repairs deaminated DNA nucleobases in cells by cleaving the phosphodiester bond, and this enzyme has proven to be a powerful tool in biotechnology and medicine. The catalytic mechanism used by EndoV must be understood to design new disease detection and therapeutic solutions and further exploit the enzyme in interdisciplinary applications. This study has used a mixed molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) approach to compare eight distinct catalytic pathways and provides the first proposed mechanism for bacterial EndoV. The calculations demonstrate that mechanisms involving either direct or indirect metal coordination to the leaving group of the substrate previously proposed for other nucleases are unlikely for EndoV, regardless of the general base (histidine, aspartate, and substrate phosphate moiety). Instead, distinct catalytic pathways are characterized for EndoV that involve K139 stabilizing the leaving group, a metal-coordinated water stabilizing the transition structure, and either H214 or a substrate phosphate group activating the water nucleophile. In silico K139A and H214A mutational results support the newly proposed roles of these residues. Although this is a previously unseen combination of general base, general acid, and metal-binding architecture for a one-metal-dependent endonuclease, our proposed catalytic mechanisms are fully consistent with experimental kinetic, structural, and mutational data. In addition to substantiating a growing body of literature, suggesting that one metal is enough to catalyze P-O bond cleavage in nucleic acids, this new fundamental understanding of the catalytic function will promote the exploration of new and improved applications of EndoV.


Asunto(s)
Ácidos Nucleicos , Desoxirribonucleasa (Dímero de Pirimidina)/química , Desoxirribonucleasa (Dímero de Pirimidina)/genética , Desoxirribonucleasa (Dímero de Pirimidina)/metabolismo , Lisina , Metales , Fosfatos , Agua
15.
Phys Chem Chem Phys ; 26(11): 8919-8931, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38426850

RESUMEN

Homing endonucleases (HEs) are highly specific DNA cleaving enzymes, with I-PpoI having been suggested to use a single metal to accelerate phosphodiester bond cleavage. Although an I-PpoI mechanism has been proposed based on experimental structural data, no consensus has been reached regarding the roles of the metal or key active site amino acids. This study uses QM cluster and QM/MM calculations to provide atomic-level details of the I-PpoI catalytic mechanism. Minimal QM cluster and large-scale QM/MM models demonstrate that the experimentally-proposed pathway involving direct Mg2+ coordination to the substrate coupled with leaving group protonation through a metal-activated water is not feasible due to an inconducive I-PpoI active site alignment. Despite QM cluster models of varying size uncovering a pathway involving leaving group protonation by a metal-activated water, indirect (water-mediated) metal coordination to the substrate is required to afford this pathway, which renders this mechanism energetically infeasible. Instead, QM cluster models reveal that the preferred pathway involves direct Mg2+-O3' coordination to stabilize the charged substrate and assist leaving group departure, while H98 activates the water nucleophile. These calculations also underscore that both catalytic residues that directly interact with the substrate and secondary amino acids that position or stabilize these residues are required for efficient catalysis. QM/MM calculations on the solvated enzyme-DNA complex verify the preferred mechanism, which is fully consistent with experimental kinetic, structural, and mutational data. The fundamental understanding of the I-PpoI mechanism of action, gained from the present work can be used to further explore potential uses of this enzyme in biotechnology and medicine, and direct future computational investigations of other members of the understudied HE family.


Asunto(s)
Endonucleasas , Metales , Metales/metabolismo , ADN/química , Catálisis , Agua
16.
Age Ageing ; 53(7)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-39011637

RESUMEN

BACKGROUND: Frailty is increasingly present in patients with acute myocardial infarction. The electronic Frailty Index (eFI) is a validated method of identifying vulnerable older patients in the community from routine primary care data. Our aim was to assess the relationship between the eFI and outcomes in older patients hospitalised with acute myocardial infarction. STUDY DESIGN AND SETTING: Retrospective cohort study using the DataLoch Heart Disease Registry comprising consecutive patients aged 65 years or over hospitalised with a myocardial infarction between October 2013 and March 2021. METHODS: Patients were classified as fit, mild, moderate, or severely frail based on their eFI score. Cox-regression analysis was used to determine the association between frailty category and all-cause mortality. RESULTS: In 4670 patients (median age 77 years [71-84], 43% female), 1865 (40%) were classified as fit, with 1699 (36%), 798 (17%) and 308 (7%) classified as mild, moderate and severely frail, respectively. In total, 1142 patients died within 12 months of which 248 (13%) and 147 (48%) were classified as fit and severely frail, respectively. After adjustment, any degree of frailty was associated with an increased risk of all-cause death with the risk greatest in the severely frail (reference = fit, adjusted hazard ratio 2.87 [95% confidence intervals 2.24 to 3.66]). CONCLUSION: The eFI identified patients at high risk of death following myocardial infarction. Automatic calculation within administrative data is feasible and could provide a low-cost method of identifying vulnerable older patients on hospital presentation.


Asunto(s)
Anciano Frágil , Fragilidad , Evaluación Geriátrica , Infarto del Miocardio , Humanos , Femenino , Masculino , Anciano , Infarto del Miocardio/mortalidad , Infarto del Miocardio/diagnóstico , Anciano de 80 o más Años , Estudios Retrospectivos , Fragilidad/diagnóstico , Fragilidad/mortalidad , Fragilidad/epidemiología , Evaluación Geriátrica/métodos , Anciano Frágil/estadística & datos numéricos , Medición de Riesgo/métodos , Sistema de Registros , Factores de Riesgo , Hospitalización/estadística & datos numéricos , Causas de Muerte
17.
Respirology ; 29(7): 596-604, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38436522

RESUMEN

BACKGROUND AND OBJECTIVE: Establishing an accurate and timely diagnosis of idiopathic pulmonary fibrosis (IPF) is essential for appropriate management and prognostication. In some cases, surgical lung biopsy (SLB) is performed but carries non-negligible risk. The objective of this retrospective study was to determine if SLB is associated with accelerated lung function decline in patients with IPF using the Canadian Registry for Pulmonary Fibrosis. METHODS: Linear mixed models and Cox proportional hazards regression models were used to compare decline in forced vital capacity (FVC)%, diffusion capacity of the lung (DLCO%) and risk of death or lung transplantation between SLB and non-SLB patients. Adjustments were made for baseline age, sex, smoking history, antifibrotic use, and lung function. A similar analysis compared lung function changes 12 months pre- and post-SLB. RESULTS: A total of 81 SLB patients and 468 non-SLB patients were included. In the SLB group, the post-biopsy annual FVC% decline was 2.0% (±0.8) in unadjusted, and 2.1% (±0.8) in adjusted models. There was no difference in FVC% decline, DLCO% decline, or time to death or lung transplantation between the two groups, in adjusted or unadjusted models (all p-values >0.07). In the pre-post SLB group, no differences were identified in FVC% decline in unadjusted or adjusted models (p = 0.07 for both). CONCLUSION: No association between SLB and lung function decline or risk of death or lung transplantation was identified in this multi-centre study of patients with IPF.


Asunto(s)
Fibrosis Pulmonar Idiopática , Pulmón , Sistema de Registros , Humanos , Fibrosis Pulmonar Idiopática/mortalidad , Fibrosis Pulmonar Idiopática/cirugía , Fibrosis Pulmonar Idiopática/fisiopatología , Fibrosis Pulmonar Idiopática/patología , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Biopsia , Pulmón/patología , Pulmón/fisiopatología , Pulmón/cirugía , Anciano , Capacidad Vital/fisiología , Trasplante de Pulmón , Canadá/epidemiología , Pruebas de Función Respiratoria , Pronóstico , Modelos de Riesgos Proporcionales , Estudios de Cohortes , Tasa de Supervivencia
18.
Eur Heart J ; 44(30): 2846-2858, 2023 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-37350492

RESUMEN

AIMS: Whether a single cardiac troponin measurement can safely rule out myocardial infarction in patients presenting within a few hours of symptom onset is uncertain. The study aim was to assess the performance of troponin in early presenters. METHODS AND RESULTS: In patients with possible myocardial infarction, the diagnostic performance of a single measurement of high-sensitivity cardiac troponin I at presentation was evaluated and externally validated in those tested ≤3, 4-12, and >12 h from symptom onset. The limit-of-detection (2 ng/L), rule-out (5 ng/L), and sex-specific 99th centile (16 ng/L in women; 34 ng/L in men) thresholds were compared. In 41 103 consecutive patients [60 (17) years, 46% women], 12 595 (31%) presented within 3 h, and 3728 (9%) had myocardial infarction. In those presenting ≤3 h, a threshold of 2 ng/L had greater sensitivity and negative predictive value [99.4% (95% confidence interval 99.2%-99.5%) and 99.7% (99.6%-99.8%)] compared with 5 ng/L [96.5% (96.2%-96.8%) and 99.3% (99.1%-99.4%)]. In those presenting ≥3 h, the sensitivity and negative predictive value were similar for both thresholds. The sensitivity of the 99th centile was low in early and late presenters at 71.4% (70.6%-72.2%) and 92.5% (92.0%-93.0%), respectively. Findings were consistent in an external validation cohort of 7088 patients. CONCLUSION: In early presenters, a single measurement of high-sensitivity cardiac troponin I below the limit of detection may facilitate the safe rule out of myocardial infarction. The 99th centile should not be used to rule out myocardial infarction at presentation even in those presenting later following symptom onset.


Asunto(s)
Infarto del Miocardio , Troponina I , Masculino , Humanos , Femenino , Biomarcadores , Infarto del Miocardio/diagnóstico , Valor Predictivo de las Pruebas , Troponina T , Servicio de Urgencia en Hospital
19.
Rev Sci Tech ; 43: 96-107, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39222107

RESUMEN

The estimation of the global burden of animal diseases requires the integration of multidisciplinary models: economic, statistical, mathematical and conceptual. The output of one model often serves as input for another; therefore, consistency of the model components is critical. The Global Burden of Animal Diseases (GBADs) Informatics team aims to strengthen the scientific foundations of modelling by creating tools that address challenges related to reproducibility, as well as model, data and metadata interoperability. Aligning with these aims, several tools are under development: a) GBADs'Trusted Animal Information Portal (TAIL) is a data acquisition platform that enhances the discoverability of data and literature and improves the user experience of acquiring data. TAIL leverages advanced semantic enrichment techniques (natural language processing and ontologies) and graph databases to provide users with a comprehensive repository of livestock data and literature resources. b) The interoperability of GBADs'models is being improved through the development of an R-based modelling package and standardisation of parameter formats. This initiative aims to foster reproducibility, facilitate data sharing and enable seamless collaboration among stakeholders. c) The GBADs Knowledge Engine is being built to foster an inclusive and dynamic user community by offering data in multiple formats and providing user-friendly mechanisms to garner feedback from the community. These initiatives are critical in addressing complex challenges in animal health and underscore the importance of combining scientific rigour with user-friendly interfaces to empower global efforts in safeguarding animal populations and public health.


L'estimation de l'impact mondial des maladies animales nécessite l'utilisation intégrée de modèles issus de diverses disciplines : économiques, statistiques, mathématiques et conceptuels. Les données de sortie d'un modèle constituent souvent celles d'entrée d'un autre modèle ; la cohérence des composantes des différents modèles est donc primordiale. L'équipe informatique du programme " Impact mondial des maladies animales " (GBADs) s'efforce de consolider les bases scientifiques de l'utilisation des modèles en mettant au point des outils permettant de résoudre les problèmes de reproductibilité et d'améliorer l'interopérabilité entre les différents modèles, données et métadonnées. En phase avec ces objectifs, plusieurs outils sont en cours de développement : a) le Portail du GBADs " Trusted Animal Information Portal " (TAIL) est une plateforme d'acquisition de données qui facilite l'accès aux données et à la littérature, tout en améliorant l'expérience utilisateur lors de l'acquisition des données. Le portail TAIL s'appuie sur des techniques avancées d'enrichissement sémantique (traitement du langage naturel et ontologies) et sur des bases de données graphiques pour apporter aux utilisateurs un référentiel complet des données et des ressources documentaires relatives aux animaux d'élevage ; b) l'interopérabilité des modèles du GBADs est en voie d'amélioration grâce à la mise au point d'un progiciel de modélisation fondé sur R et à la normalisation des formats de paramètres. Cette initiative vise à favoriser la reproductibilité, à faciliter le partage de données et à permettre une collaboration transparente entre les parties prenantes ; c) le moteur de connaissances du GBADs, en cours de construction, vise à encourager une communauté d'utilisateurs inclusive et dynamique en proposant des données dans une multiplicité de formats ainsi que des mécanismes conviviaux pour recueillir les commentaires de la communauté. Ces initiatives se révéleront indispensables pour relever les défis complexes de la santé animale et soulignent l'importance d'associer une grande rigueur scientifique à la convivialité des interfaces, afin de donner encore plus d'élan aux efforts déployés dans le monde pour protéger les populations animales et la santé publique.


La estimación del impacto global de las enfermedades animales requiere la integración de modelos multidisciplinarios: económicos, estadísticos, matemáticos y conceptuales. El resultado de un modelo a menudo sirve de entrada para otro; por lo tanto, la coherencia entre los distintos componentes es fundamental. El equipo de informática del programa sobre el Impacto Global de las Enfermedades Animales (GBADs) tiene como objetivo fortalecer los fundamentos científicos de la modelización mediante la creación de herramientas que aborden los retos relacionados con la reproducibilidad, así como con la interoperabilidad de los modelos, datos y metadatos. En consonancia con estos objetivos, se están desarrollando varias herramientas: a) El Portal del GBADs "Trusted Animal Information Portal" (TAIL) es una plataforma de adquisición de datos que mejora tanto la descubribilidad de datos y bibliografía como la experiencia del usuario a la hora de obtener datos. El portal TAIL utiliza técnicas avanzadas de enriquecimiento semántico (procesamiento del lenguaje natural y ontologías), así como bases de datos de grafos, para ofrecer a los usuarios un repositorio completo de datos sobre ganadería y recursos bibliográficos. b) Se está mejorando la interoperabilidad de los modelos del GBADs mediante el desarrollo de un paquete de modelización en R y la normalización de los formatos de los parámetros. Esta iniciativa pretende fomentar la reproducibilidad, facilitar el intercambio de datos y permitir una colaboración fluida entre las partes interesadas. c) El Motor de Conocimiento del GBADs se está construyendo con el objetivo de fomentar una comunidad de usuarios inclusiva y dinámica, ofreciendo datos en diferentes formatos y proporcionando mecanismos fáciles de usar para recopilar comentarios de la comunidad. Estas iniciativas son fundamentales para hacer frente a los complejos retos en el ámbito de la sanidad animal y subrayan la importancia de combinar el rigor científico con interfaces fáciles de usar para potenciar los esfuerzos mundiales encaminados a proteger a las poblaciones animales y la salud pública.


Asunto(s)
Enfermedades de los Animales , Exactitud de los Datos , Animales , Enfermedades de los Animales/prevención & control , Salud Global , Bases de Datos Factuales
20.
J Environ Manage ; 364: 121484, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38878567

RESUMEN

Sustainable soil resource management depends on reliable soil information, often derived from 'legacy soil data' or a combination of old and new soil data. However, the task of harmonizing soil data collected at different times remains a largely unexplored in the literature. Addressing this challenge requires incorporating the temporal dimension into mathematical and statistical models for spatio-temporal soil studies. This study aimed to create a comprehensive framework for harmonizing soil data across various time. We assessed the integration of historical and recent soil data, ranging from 4 to 48 years old data, using soil data recency analysis. To achieve this, we introduced an 'age of data' attribute, calculating the time difference between soil survey years and the present (e.g., 2022). We applied three machine learning models - Decision Trees (DT), Random Forest (RF), Gradient Boosting (GBM) - to a dataset containing 6339 sites and 28,149 depth-harmonized layers. The results consistently demonstrated robust performance across models, RF outperforming with an R-squared value of 0.99, RMSE of 1.41, and a concordance of 0.97. Similarly, DT and GBM also showed strong predictive power. Terrain-derived environmental covariates played a more important role than land use and land cover (LULC) change in predicting soil data recency. While LULC change showed soil organic carbon concentration variability across the different depths, it was a less important factor. Anthropogenic factors, such as LULC change and normalized difference vegetation index (NDVI), were not primary determinants of soil data recency. Variations in soil depth had no impact on predicting soil data recency. This study validated that terrain-derived covariates, especially elevation factors, effectively explain the quality of older soil data when predicting current soil attributes using the soil data recency concept. This approach has the potential to enhance real-time estimates, such as carbon budgets, and we emphasize its importance in global earth system models.


Asunto(s)
Aprendizaje Automático , Suelo , Suelo/química , Monitoreo del Ambiente/métodos
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