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1.
Cell ; 180(4): 764-779.e20, 2020 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-32059779

RESUMEN

The heterogeneity of endothelial cells (ECs) across tissues remains incompletely inventoried. We constructed an atlas of >32,000 single-EC transcriptomes from 11 mouse tissues and identified 78 EC subclusters, including Aqp7+ intestinal capillaries and angiogenic ECs in healthy tissues. ECs from brain/testis, liver/spleen, small intestine/colon, and skeletal muscle/heart pairwise expressed partially overlapping marker genes. Arterial, venous, and lymphatic ECs shared more markers in more tissues than did heterogeneous capillary ECs. ECs from different vascular beds (arteries, capillaries, veins, lymphatics) exhibited transcriptome similarity across tissues, but the tissue (rather than the vessel) type contributed to the EC heterogeneity. Metabolic transcriptome analysis revealed a similar tissue-grouping phenomenon of ECs and heterogeneous metabolic gene signatures in ECs between tissues and between vascular beds within a single tissue in a tissue-type-dependent pattern. The EC atlas taxonomy enabled identification of EC subclusters in public scRNA-seq datasets and provides a powerful discovery tool and resource value.


Asunto(s)
Células Endoteliales/metabolismo , Análisis de la Célula Individual , Transcriptoma , Animales , Encéfalo/citología , Sistema Cardiovascular/citología , Células Endoteliales/clasificación , Células Endoteliales/citología , Tracto Gastrointestinal/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Músculos/citología , Especificidad de Órganos , RNA-Seq , Testículo/citología
2.
Nature ; 622(7981): 41-47, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37794265

RESUMEN

Scientists have been trying to identify every gene in the human genome since the initial draft was published in 2001. In the years since, much progress has been made in identifying protein-coding genes, currently estimated to number fewer than 20,000, with an ever-expanding number of distinct protein-coding isoforms. Here we review the status of the human gene catalogue and the efforts to complete it in recent years. Beside the ongoing annotation of protein-coding genes, their isoforms and pseudogenes, the invention of high-throughput RNA sequencing and other technological breakthroughs have led to a rapid growth in the number of reported non-coding RNA genes. For most of these non-coding RNAs, the functional relevance is currently unclear; we look at recent advances that offer paths forward to identifying their functions and towards eventually completing the human gene catalogue. Finally, we examine the need for a universal annotation standard that includes all medically significant genes and maintains their relationships with different reference genomes for the use of the human gene catalogue in clinical settings.


Asunto(s)
Genes , Genoma Humano , Anotación de Secuencia Molecular , Isoformas de Proteínas , Humanos , Genoma Humano/genética , Anotación de Secuencia Molecular/normas , Anotación de Secuencia Molecular/tendencias , Isoformas de Proteínas/genética , Proyecto Genoma Humano , Seudogenes , ARN/genética
3.
Nature ; 606(7915): 678-682, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35732764

RESUMEN

A long-standing question in nuclear physics is whether chargeless nuclear systems can exist. To our knowledge, only neutron stars represent near-pure neutron systems, where neutrons are squeezed together by the gravitational force to very high densities. The experimental search for isolated multi-neutron systems has been an ongoing quest for several decades1, with a particular focus on the four-neutron system called the tetraneutron, resulting in only a few indications of its existence so far2-4, leaving the tetraneutron an elusive nuclear system for six decades. Here we report on the observation of a resonance-like structure near threshold in the four-neutron system that is consistent with a quasi-bound tetraneutron state existing for a very short time. The measured energy and width of this state provide a key benchmark for our understanding of the nuclear force. The use of an experimental approach based on a knockout reaction at large momentum transfer with a radioactive high-energy 8He beam was key.

4.
Nature ; 604(7905): 310-315, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35388217

RESUMEN

Comprehensive genome annotation is essential to understand the impact of clinically relevant variants. However, the absence of a standard for clinical reporting and browser display complicates the process of consistent interpretation and reporting. To address these challenges, Ensembl/GENCODE1 and RefSeq2 launched a joint initiative, the Matched Annotation from NCBI and EMBL-EBI (MANE) collaboration, to converge on human gene and transcript annotation and to jointly define a high-value set of transcripts and corresponding proteins. Here, we describe the MANE transcript sets for use as universal standards for variant reporting and browser display. The MANE Select set identifies a representative transcript for each human protein-coding gene, whereas the MANE Plus Clinical set provides additional transcripts at loci where the Select transcripts alone are not sufficient to report all currently known clinical variants. Each MANE transcript represents an exact match between the exonic sequences of an Ensembl/GENCODE transcript and its counterpart in RefSeq such that the identifiers can be used synonymously. We have now released MANE Select transcripts for 97% of human protein-coding genes, including all American College of Medical Genetics and Genomics Secondary Findings list v3.0 (ref. 3) genes. MANE transcripts are accessible from major genome browsers and key resources. Widespread adoption of these transcript sets will increase the consistency of reporting, facilitate the exchange of data regardless of the annotation source and help to streamline clinical interpretation.


Asunto(s)
Biología Computacional , Bases de Datos Genéticas , Genómica , Genoma , Humanos , Difusión de la Información , Anotación de Secuencia Molecular , National Library of Medicine (U.S.) , Estados Unidos
5.
PLoS Biol ; 22(5): e3002405, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38713717

RESUMEN

We report a new visualization tool for analysis of whole-genome assembly-assembly alignments, the Comparative Genome Viewer (CGV) (https://ncbi.nlm.nih.gov/genome/cgv/). CGV visualizes pairwise same-species and cross-species alignments provided by National Center for Biotechnology Information (NCBI) using assembly alignment algorithms developed by us and others. Researchers can examine large structural differences spanning chromosomes, such as inversions or translocations. Users can also navigate to regions of interest, where they can detect and analyze smaller-scale deletions and rearrangements within specific chromosome or gene regions. RefSeq or user-provided gene annotation is displayed where available. CGV currently provides approximately 800 alignments from over 350 animal, plant, and fungal species. CGV and related NCBI viewers are undergoing active development to further meet needs of the research community in comparative genome visualization.


Asunto(s)
Genoma , Programas Informáticos , Animales , Genoma/genética , Alineación de Secuencia/métodos , Genómica/métodos , Algoritmos , Estados Unidos , Humanos , Eucariontes/genética , Bases de Datos Genéticas , National Library of Medicine (U.S.) , Anotación de Secuencia Molecular/métodos
6.
Cell ; 150(2): 264-78, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22817890

RESUMEN

Most mutations in cancer genomes are thought to be acquired after the initiating event, which may cause genomic instability and drive clonal evolution. However, for acute myeloid leukemia (AML), normal karyotypes are common, and genomic instability is unusual. To better understand clonal evolution in AML, we sequenced the genomes of M3-AML samples with a known initiating event (PML-RARA) versus the genomes of normal karyotype M1-AML samples and the exomes of hematopoietic stem/progenitor cells (HSPCs) from healthy people. Collectively, the data suggest that most of the mutations found in AML genomes are actually random events that occurred in HSPCs before they acquired the initiating mutation; the mutational history of that cell is "captured" as the clone expands. In many cases, only one or two additional, cooperating mutations are needed to generate the malignant founding clone. Cells from the founding clone can acquire additional cooperating mutations, yielding subclones that can contribute to disease progression and/or relapse.


Asunto(s)
Evolución Clonal , Leucemia Mieloide Aguda/genética , Mutación , Adulto , Anciano , Análisis Mutacional de ADN , Progresión de la Enfermedad , Femenino , Estudio de Asociación del Genoma Completo , Células Madre Hematopoyéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/fisiopatología , Masculino , Persona de Mediana Edad , Proteínas de Fusión Oncogénica/genética , Recurrencia , Piel/metabolismo , Adulto Joven
7.
CA Cancer J Clin ; 69(1): 35-49, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30376182

RESUMEN

Cancer care delivery is being shaped by growing numbers of cancer survivors coupled with provider shortages, rising costs of primary treatment and follow-up care, significant survivorship health disparities, increased reliance on informal caregivers, and the transition to value-based care. These factors create a compelling need to provide coordinated, comprehensive, personalized care for cancer survivors in ways that meet survivors' and caregivers' unique needs while minimizing the impact of provider shortages and controlling costs for health care systems, survivors, and families. The authors reviewed research identifying and addressing the needs of cancer survivors and caregivers and used this synthesis to create a set of critical priorities for care delivery, research, education, and policy to equitably improve survivor outcomes and support caregivers. Efforts are needed in 3 priority areas: 1) implementing routine assessment of survivors' needs and functioning and caregivers' needs; 2) facilitating personalized, tailored, information and referrals from diagnosis onward for both survivors and caregivers, shifting services from point of care to point of need wherever possible; and 3) disseminating and supporting the implementation of new care methods and interventions.


Asunto(s)
Supervivientes de Cáncer , Cuidadores , Política de Salud , Accesibilidad a los Servicios de Salud/organización & administración , Disparidades en Atención de Salud/organización & administración , Mejoramiento de la Calidad/organización & administración , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Investigación Biomédica/métodos , Investigación Biomédica/organización & administración , Supervivientes de Cáncer/estadística & datos numéricos , Niño , Preescolar , Medicina Basada en la Evidencia/métodos , Medicina Basada en la Evidencia/organización & administración , Femenino , Disparidades en el Estado de Salud , Humanos , Lactante , Recién Nacido , Masculino , Área sin Atención Médica , Persona de Mediana Edad , Evaluación de Necesidades , Evaluación de Procesos y Resultados en Atención de Salud , Atención Dirigida al Paciente/métodos , Atención Dirigida al Paciente/organización & administración , Derivación y Consulta/organización & administración , Apoyo Social , Estados Unidos , Adulto Joven
8.
Nucleic Acids Res ; 52(D1): D134-D137, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37889039

RESUMEN

GenBank® (https://www.ncbi.nlm.nih.gov/genbank/) is a comprehensive, public database that contains 25 trillion base pairs from over 3.7 billion nucleotide sequences for 557 000 formally described species. Daily data exchange with the European Nucleotide Archive (ENA) and the DNA Data Bank of Japan (DDBJ) ensures worldwide coverage. Recent updates include policies for including spatio-temporal metadata, clarified documentation for GenBank data processing, enhanced foreign contamination screening tools, new processes in the Submission Portal, migration of Entrez Genome and Assembly displays into NCBI Datasets, and the impending retirement of tbl2asn, replaced by table2asn.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , Genómica , Secuencia de Bases , Internet , Humanos
9.
Nucleic Acids Res ; 52(D1): D33-D43, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37994677

RESUMEN

The National Center for Biotechnology Information (NCBI) provides online information resources for biology, including the GenBank® nucleic acid sequence database and the PubMed® database of citations and abstracts published in life science journals. NCBI provides search and retrieval operations for most of these data from 35 distinct databases. The E-utilities serve as the programming interface for most of these databases. Resources receiving significant updates in the past year include PubMed, PMC, Bookshelf, SciENcv, the NIH Comparative Genomics Resource (CGR), NCBI Virus, SRA, RefSeq, foreign contamination screening tools, Taxonomy, iCn3D, ClinVar, GTR, MedGen, dbSNP, ALFA, ClinicalTrials.gov, Pathogen Detection, antimicrobial resistance resources, and PubChem. These resources can be accessed through the NCBI home page at https://www.ncbi.nlm.nih.gov.


Asunto(s)
Bases de Datos Genéticas , National Library of Medicine (U.S.) , Biotecnología/instrumentación , Bases de Datos de Ácidos Nucleicos , Internet , Estados Unidos
10.
Genome Res ; 32(1): 175-188, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34876495

RESUMEN

Eukaryotic genomes contain many nongenic elements that function in gene regulation, chromosome organization, recombination, repair, or replication, and mutation of those elements can affect genome function and cause disease. Although numerous epigenomic studies provide high coverage of gene regulatory regions, those data are not usually exposed in traditional genome annotation and can be difficult to access and interpret without field-specific expertise. The National Center for Biotechnology Information (NCBI) therefore provides RefSeq Functional Elements (RefSeqFEs), which represent experimentally validated human and mouse nongenic elements derived from the literature. The curated data set is comprised of richly annotated sequence records, descriptive records in the NCBI Gene database, reference genome feature annotation, and activity-based interactions between nongenic regions, target genes, and each other. The data set provides succinct functional details and transparent experimental evidence, leverages data from multiple experimental sources, is readily accessible and adaptable, and uses a flexible data model. The data have multiple uses for basic functional discovery, bioinformatics studies, genetic variant interpretation; as known positive controls for epigenomic data evaluation; and as reference standards for functional interactions. Comparisons to other gene regulatory data sets show that the RefSeqFE data set includes a wider range of feature types representing more areas of biology, but it is comparatively smaller and subject to data selection biases. RefSeqFEs thus provide an alternative and complementary resource for experimentally assayed functional elements, with future data set growth expected.


Asunto(s)
Biología Computacional , Genoma , Animales , Bases de Datos Genéticas , Eucariontes/genética , Humanos , Ratones , Estándares de Referencia
11.
Nucleic Acids Res ; 51(D1): D141-D144, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36350640

RESUMEN

GenBank® (https://www.ncbi.nlm.nih.gov/genbank/) is a comprehensive, public database that contains 19.6 trillion base pairs from over 2.9 billion nucleotide sequences for 504 000 formally described species. Daily data exchange with the European Nucleotide Archive (ENA) and the DNA Data Bank of Japan (DDBJ) ensures worldwide coverage. Recent updates include resources for data from the SARS-CoV-2 virus, NCBI Datasets, BLAST ClusteredNR, the Submission Portal, table2asn, a Foreign Contamination Screening tool and BioSample.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , Humanos , COVID-19/genética , Genómica , SARS-CoV-2/genética
12.
Nucleic Acids Res ; 51(D1): D29-D38, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36370100

RESUMEN

The National Center for Biotechnology Information (NCBI) provides online information resources for biology, including the GenBank® nucleic acid sequence database and the PubMed® database of citations and abstracts published in life science journals. NCBI provides search and retrieval operations for most of these data from 35 distinct databases. The E-utilities serve as the programming interface for most of these databases. New resources include the Comparative Genome Resource (CGR) and the BLAST ClusteredNR database. Resources receiving significant updates in the past year include PubMed, PMC, Bookshelf, IgBLAST, GDV, RefSeq, NCBI Virus, GenBank type assemblies, iCn3D, ClinVar, GTR, dbGaP, ALFA, ClinicalTrials.gov, Pathogen Detection, antimicrobial resistance resources, and PubChem. These resources can be accessed through the NCBI home page at https://www.ncbi.nlm.nih.gov.


Asunto(s)
Bases de Datos Genéticas , Bases de Datos de Ácidos Nucleicos , Estados Unidos , National Library of Medicine (U.S.) , Alineación de Secuencia , Biotecnología , Internet
13.
Proc Natl Acad Sci U S A ; 119(10): e2112397119, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35239443

RESUMEN

SignificanceThe modulation of growth hormone secretagogue receptor-1a (GHSR1a) signaling is a promising strategy for treating brain conditions of metabolism, aging, and addiction. GHSR1a activation results in pleiotropic physiological outcomes through distinct and pharmacologically separable G protein- and ß-arrestin (ßarr)-dependent signaling pathways. Thus, pathway-selective modulation can enable improved pharmacotherapeutics that can promote therapeutic efficacy while mitigating side effects. Here, we describe the discovery of a brain-penetrant small molecule, N8279 (NCATS-SM8864), that biases GHSR1a conformations toward Gαq activation and reduces aberrant dopaminergic behavior in mice. N8279 represents a promising chemical scaffold to advance the development of better treatments for GHSR1a-related brain disorders involving the pathological dysregulation of dopamine.


Asunto(s)
Encéfalo/metabolismo , Dopamina/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Receptores de Ghrelina/metabolismo , Animales , Dopamina/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Masculino , Ratones , Ratones Noqueados , Receptores de Ghrelina/genética
14.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35042802

RESUMEN

A global international initiative, such as the Earth BioGenome Project (EBP), requires both agreement and coordination on standards to ensure that the collective effort generates rapid progress toward its goals. To this end, the EBP initiated five technical standards committees comprising volunteer members from the global genomics scientific community: Sample Collection and Processing, Sequencing and Assembly, Annotation, Analysis, and IT and Informatics. The current versions of the resulting standards documents are available on the EBP website, with the recognition that opportunities, technologies, and challenges may improve or change in the future, requiring flexibility for the EBP to meet its goals. Here, we describe some highlights from the proposed standards, and areas where additional challenges will need to be met.


Asunto(s)
Secuencia de Bases/genética , Eucariontes/genética , Genómica/normas , Animales , Biodiversidad , Genómica/métodos , Humanos , Estándares de Referencia , Valores de Referencia , Análisis de Secuencia de ADN/métodos , Análisis de Secuencia de ADN/normas
15.
J Neurophysiol ; 131(3): 556-561, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38324895

RESUMEN

Sport-related concussion (SRC) is known to disrupt neurohemodynamic activity, cardiac function, and blood pressure (BP) autoregulation. This study aims to observe changes in cerebrovascular and cardiovascular responses during controlled respiration after sustaining an SRC. University varsity athletes (n = 81) completed a preseason physiological assessment and were followed up within 5 days of sustaining an SRC. During preseason and follow-up assessments, participants' continuous beat-to-beat BP was collected by finger photoplethysmography, and right prefrontal cortex oxygenation was collected using near-infrared spectroscopy (NIRS). Participants completed 5 min of seated rest and 5 min of a 6-breaths per minute controlled breathing protocol (5 s inhale and 5 s exhale; 0.10 Hz). Wavelet transformation was applied to the NIRS and BP signals, separating them into respiratory (0.10-0.6 Hz) and cardiac (0.6-2 Hz) frequency intervals. Of the 81 participants, 74 had a usable BP signal, 43 had usable NIRS signals, and 28 had both usable BP and NIRS signals. Wavelet amplitudes were calculated and coherence between NIRS and BP on the 28 participants were assessed. There was a significant (P < 0.05) decrease in oxygenated hemoglobin amplitude from 0.062 to 0.054 Hz and hemoglobin difference amplitude from 0.059 to 0.051 Hz, both at the respiratory (0.10-0.6 Hz) frequency interval, from preseason to acute SRC, respectively. Therefore, during controlled respiration, there was a reduction in intensity at the respiratory band, suggesting a protective, reduced respiratory contribution to cerebral hemodynamic activity following acute SRC.NEW & NOTEWORTHY This study investigated cerebral hemodynamic activity following sport-related concussion. Prefrontal cortex oxygenation was assessed by near-infrared spectroscopy (NIRS) during a controlled breathing protocol. Wavelet transformation of the NIRS signals showed significant decreases in HbO2 and HbD amplitude at the respiratory frequency interval (0.10-0.6 HZ) from preseason baseline to acute concussion. These results suggest a decreased respiratory contribution to cerebral hemodynamic activity following acute concussion.


Asunto(s)
Conmoción Encefálica , Hemodinámica , Humanos , Corteza Prefrontal , Hemoglobinas , Respiración , Circulación Cerebrovascular/fisiología
16.
Ann Oncol ; 35(5): 437-447, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38369013

RESUMEN

BACKGROUND: Human epidermal growth factor receptor 3 (HER3) is broadly expressed in non-small-cell lung cancer (NSCLC) and is the target of patritumab deruxtecan (HER3-DXd), an antibody-drug conjugate consisting of a HER3 antibody attached to a topoisomerase I inhibitor payload via a tetrapeptide-based cleavable linker. U31402-A-U102 is an ongoing phase I study of HER3-DXd in patients with advanced NSCLC. Patients with epidermal growth factor receptor (EGFR)-mutated NSCLC that progressed after EGFR tyrosine kinase inhibitor (TKI) and platinum-based chemotherapy (PBC) who received HER3-DXd 5.6 mg/kg intravenously once every 3 weeks had a confirmed objective response rate (cORR) of 39%. We present median overall survival (OS) with extended follow-up in a larger population of patients with EGFR-mutated NSCLC and an exploratory analysis in those with acquired genomic alterations potentially associated with resistance to HER3-DXd. PATIENTS AND METHODS: Safety was assessed in patients with EGFR-mutated NSCLC previously treated with EGFR TKI who received HER3-DXd 5.6 mg/kg; efficacy was assessed in those who also had prior PBC. RESULTS: In the safety population (N = 102), median treatment duration was 5.5 (range 0.7-27.5) months. Grade ≥3 adverse events occurred in 76.5% of patients; the overall safety profile was consistent with previous reports. In 78/102 patients who had prior third-generation EGFR TKI and PBC, cORR by blinded independent central review (as per RECIST v1.1) was 41.0% [95% confidence interval (CI) 30.0% to 52.7%], median progression-free survival was 6.4 (95% CI 4.4-10.8) months, and median OS was 16.2 (95% CI 11.2-21.9) months. Patients had diverse mechanisms of EGFR TKI resistance at baseline. At tumor progression, acquired mutations in ERBB3 and TOP1 that might confer resistance to HER3-DXd were identified. CONCLUSIONS: In patients with EGFR-mutated NSCLC after EGFR TKI and PBC, HER3-DXd treatment was associated with a clinically meaningful OS. The tumor biomarker characterization comprised the first description of potential mechanisms of resistance to HER3-DXd therapy.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Carcinoma de Pulmón de Células no Pequeñas , Receptores ErbB , Neoplasias Pulmonares , Mutación , Receptor ErbB-3 , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Receptores ErbB/genética , Receptores ErbB/antagonistas & inhibidores , Femenino , Receptor ErbB-3/genética , Receptor ErbB-3/antagonistas & inhibidores , Persona de Mediana Edad , Masculino , Anciano , Adulto , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anciano de 80 o más Años , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Camptotecina/administración & dosificación , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos ampliamente neutralizantes , Inmunoconjugados/uso terapéutico , Inmunoconjugados/efectos adversos , Inmunoconjugados/administración & dosificación
17.
Glob Chang Biol ; 30(2): e17190, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38403855

RESUMEN

Enhancement of net primary production (NPP) in forests as atmospheric [CO2 ] increases is likely limited by the availability of other growth resources. The Duke Free Air CO2 Enrichment (FACE) experiment was located on a moderate-fertility site in the southeastern US, in a loblolly pine (Pinus taeda L.) plantation with broadleaved species growing mostly in mid-canopy and understory. Duke FACE ran from 1994 to 2010 and combined elevated [CO2 ] (eCO2 ) with nitrogen (N) additions. We assessed the spatial and temporal variation of NPP response using a dataset that includes previously unpublished data from 6 years of the replicated CO2 × N experiment and extends to 2 years beyond the termination of enrichment. Averaged over time (1997-2010), NPP of pine and broadleaved species were 38% and 52% higher under eCO2 compared to ambient conditions. Furthermore, there was no evidence of a decline in enhancement over time in any plot regardless of its native site quality. The relation between spatial variation in the response and native site quality was suggested but inconclusive. Nitrogen amendments under eCO2 , in turn, resulted in an additional 11% increase in pine NPP. For pine, the eCO2 -induced increase in NPP was similar above- and belowground and was driven by both increased leaf area index (L) and production efficiency (PE = NPP/L). For broadleaved species, coarse-root biomass production was more than 200% higher under eCO2 and accounted for the entire production response, driven by increased PE. Notably, the fraction of annual NPP retained in total living biomass was higher under eCO2 , reflecting a slight shift in allocation fraction to woody mass and a lower mortality rate. Our findings also imply that tree growth may not have been only N-limited, but perhaps constrained by the availability of other nutrients. The observed sustained NPP enhancement, even without N-additions, demonstrates no progressive N limitation.


Asunto(s)
Dióxido de Carbono , Pinus , Nitrógeno , Pinus/fisiología , Bosques , Árboles , Pinus taeda , Hojas de la Planta/fisiología
18.
Phys Rev Lett ; 132(8): 082501, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457706

RESUMEN

The structure and decay of the most neutron-rich beryllium isotope, ^{16}Be, has been investigated following proton knockout from a high-energy ^{17}B beam. Two relatively narrow resonances were observed for the first time, with energies of 0.84(3) and 2.15(5) MeV above the two-neutron decay threshold and widths of 0.32(8) and 0.95(15) MeV, respectively. These were assigned to be the ground (J^{π}=0^{+}) and first excited (2^{+}) state, with E_{x}=1.31(6) MeV. The mass excess of ^{16}Be was thus deduced to be 56.93(13) MeV, some 0.5 MeV more bound than the only previous measurement. Both states were observed to decay by direct two-neutron emission. Calculations incorporating the evolution of the wave function during the decay as a genuine three-body process reproduced the principal characteristics of the neutron-neutron energy spectra for both levels, indicating that the ground state exhibits a strong spatially compact dineutron component, while the 2^{+} level presents a far more diffuse neutron-neutron distribution.

19.
Int J Behav Nutr Phys Act ; 21(1): 18, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373957

RESUMEN

Numerous research methodologies have been used to examine food environments. Existing reviews synthesizing food environment measures have examined a limited number of domains or settings and none have specifically targeted Canada. This rapid review aimed to 1) map research methodologies and measures that have been used to assess food environments; 2) examine what food environment dimensions and equity related-factors have been assessed; and 3) identify research gaps and priorities to guide future research. A systematic search of primary articles evaluating the Canadian food environment in a real-world setting was conducted. Publications in English or French published in peer-reviewed journals between January 1 2010 and June 17 2021 and indexed in Web of Science, CAB Abstracts and Ovid MEDLINE were considered. The search strategy adapted an internationally-adopted food environment monitoring framework covering 7 domains (Food Marketing; Labelling; Prices; Provision; Composition; Retail; and Trade and Investment). The final sample included 220 articles. Overall, Trade and Investment (1%, n = 2), Labelling (7%, n = 15) and, to a lesser extent, Prices (14%, n = 30) were the least studied domains in Canada. Among Provision articles, healthcare (2%, n = 1) settings were underrepresented compared to school (67%, n = 28) and recreation and sport (24%, n = 10) settings, as was the food service industry (14%, n = 6) compared to grocery stores (86%, n = 36) in the Composition domain. The study identified a vast selection of measures employed in Canada overall and within single domains. Equity-related factors were only examined in half of articles (n = 108), mostly related to Retail (n = 81). A number of gaps remain that prevent a holistic and systems-level analysis of food environments in Canada. As Canada continues to implement policies to improve the quality of food environments in order to improve dietary patterns, targeted research to address identified gaps and harmonize methods across studies will help evaluate policy impact over time.


Asunto(s)
Alimentos , Mercadotecnía , Humanos , Canadá , Industria de Alimentos , Instituciones Académicas
20.
Scand J Rheumatol ; 53(4): 248-254, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38686835

RESUMEN

OBJECTIVE: To evaluate the prevalence and rate of a missed diagnosis of sacroiliitis on abdominal computed tomography (CT) in patients with inflammatory bowel disease (IBD). Factors associated with sacroiliitis were also assessed. METHOD: This retrospective study included 210 patients with IBD (mean age 31.1 years) who underwent abdominal CT. Based on a validated abdominal CT scoring tool, bilateral sacroiliac (SI) joints on abdominal CT in the whole study population were retrospectively reviewed. Subsequently, patients were classified into the 'patients with sacroiliitis' group and the 'patients without sacroiliitis' group. Univariate and multivariate regression analyses were used to clarify the factors associated with sacroiliitis. RESULTS: Sacroiliitis was identified in 26 out of 210 patients (12.4%). However, sacroiliitis was recognized on the primary reading in only five of these 26 patients (19.2%) and was missed on the initial report in the remaining 21 patients (80.8%). Among the 21 patients, 20 (95.2%) were finally diagnosed with axial spondyloarthritis (axSpA). There was a higher prevalence of female sex (p = 0.04), upper gastrointestinal involvement (p = 0.04), and back pain (p < 0.01) in patients with sacroiliitis than in those without sacroiliitis. However, on multivariate analysis, back pain was the only factor associated with sacroiliitis (p = 0.01). CONCLUSION: Physicians should carefully evaluate SI joints on abdominal CT in patients with IBD to enable early detection of sacroiliitis, potentially leading to an early diagnosis of axSpA. In addition, if patients with IBD present with back pain, the possibility of sacroiliitis should be considered.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Sacroileítis , Tomografía Computarizada por Rayos X , Humanos , Femenino , Masculino , Sacroileítis/diagnóstico por imagen , Sacroileítis/epidemiología , Adulto , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Enfermedades Inflamatorias del Intestino/epidemiología , Enfermedades Inflamatorias del Intestino/diagnóstico por imagen , Enfermedades Inflamatorias del Intestino/complicaciones , Prevalencia , Persona de Mediana Edad , Adulto Joven , Diagnóstico Erróneo/estadística & datos numéricos , Articulación Sacroiliaca/diagnóstico por imagen , Espondiloartritis Axial/epidemiología , Espondiloartritis Axial/diagnóstico por imagen
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