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1.
Bioscience ; 68(2): 112-124, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29599548

RESUMO

The digitization of biocollections is a critical task with direct implications for the global community who use the data for research and education. Recent innovations to involve citizen scientists in digitization increase awareness of the value of biodiversity specimens; advance science, technology, engineering, and math literacy; and build sustainability for digitization. In support of these activities, we launched the first global citizen-science event focused on the digitization of biodiversity specimens: Worldwide Engagement for Digitizing Biocollections (WeDigBio). During the inaugural 2015 event, 21 sites hosted events where citizen scientists transcribed specimen labels via online platforms (DigiVol, Les Herbonautes, Notes from Nature, the Smithsonian Institution's Transcription Center, and Symbiota). Many citizen scientists also contributed off-site. In total, thousands of citizen scientists around the world completed over 50,000 transcription tasks. Here, we present the process of organizing an international citizen-science event, an analysis of the event's effectiveness, and future directions-content now foundational to the growing WeDigBio event.

2.
Catheter Cardiovasc Interv ; 91(5): 894-896, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28944588

RESUMO

Mechanical cardiovascular support devices are now widely used both in the setting of cardiogenic shock as well as during high risk cardiac catheterization procedures. We report a case of a young female patient who presented with presumed myocarditis and rapidly deteriorating decompensated heart failure requiring the implantation of an Impella Circulatory Support System. Upon transfer to our facility it was discovered that during transport, the Impella device had migrated through the left ventricle. She was emergently taken to the operating room where the Impella was surgically removed and biventricular support devices were placed. The patient eventually expired after weeks of treatment in the intensive care unit. We believe this is the first recorded case of an Impella device perforating the left ventricle. Particularly in cases of newly discovered pericardial effusion, change in waveform on the Impella controller placement signal or rapid decompensation, physicians should consider this rare but potentially catastrophic complication associated with mechanical left ventricular support devices.


Assuntos
Traumatismos Cardíacos/etiologia , Ventrículos do Coração/lesões , Coração Auxiliar , Implantação de Prótese/efeitos adversos , Implantação de Prótese/instrumentação , Choque Cardiogênico/terapia , Função Ventricular Esquerda , Adulto , Evolução Fatal , Feminino , Traumatismos Cardíacos/diagnóstico , Traumatismos Cardíacos/fisiopatologia , Traumatismos Cardíacos/terapia , Ventrículos do Coração/fisiopatologia , Humanos , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/etiologia , Choque Cardiogênico/fisiopatologia
3.
J Environ Manage ; 204(Pt 2): 793-803, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28233638

RESUMO

The last decade has seen a growing interest in applying activated carbon (AC)-based amendments for in situ subsurface remediation of organic contaminants such as chlorinated solvents and petroleum hydrocarbons. This remedial technology has been promoted by several major AC-based product vendors on the market. These products involve impregnation or co-application of chemical or biological additives to facilitate various contaminant degradation processes in conjunction with contaminant adsorption. During field applications, rapid contaminant removal and limited rebound after emplacement have often been reported and considered as two major advantages for this remedial technology. Nevertheless, questions remain to be answered regarding its true effectiveness and longevity given the lack of subsequent field characterizations and evidence of the degradation process, especially biodegradation. Additional uncertainties reside in how subsurface heterogeneity may affect the design, implementation and performance monitoring of this technology. In light of these uncertainties, this review presents an independent analysis that focuses on both the scientific and practical aspects of AC-based remedial technology for in situ subsurface remediation by gathering and synthesizing the scientific knowledge and practical lessons from a broad range of contaminant removal processes involving adsorption and/or degradation. The analysis showed that the scientific soundness of combining adsorption and degradation proposed for all the AC-based products is well supported by the literature on ex situ treatment. However, the in situ effectiveness might be affected by additional factors, such as geological heterogeneity, amendment transport and distribution, and total contaminant mass, which require more thorough and quantitative evaluation. Overall, the technology may provide a viable tool in addressing major remediation challenges encountered in current practice, such as mitigation of back diffusion from residual sources in low permeability zones and treatment of low concentration plumes.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Adsorção , Biodegradação Ambiental , Purificação da Água
5.
Clin Transplant ; 29(9): 829-34, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26171948

RESUMO

BACKGROUND: The elevated baseline heart rate (HR) of a heart transplant recipient has previously been considered inconsequential. However, we hypothesized that a resting HR above 100 beats per minute (bpm) may be associated with morbidity and mortality. METHODS: The U.T.A.H. Cardiac Transplant Program studied patients who received a heart transplant between 2000 and 2011. Outpatient HR values for each patient were averaged during the first year post-transplant. The study cohort was divided into two groups: the tachycardic (TC) (HR > 100 bpm) and the non-TC group (HR ≤ 100 bpm) in which mortality, incidence of rejection, and cardiac allograft vasculopathy were compared. RESULTS: Three hundred and ten patients were included as follows: 73 in the TC and 237 in the non-TC group. The TC group had a higher risk of a 10-yr all-cause mortality (p = 0.004) and cardiovascular mortality (p = 0.044). After adjustment for donor and recipient characteristics in multivariable logistic regression analysis, the hazard ratio was 3.9, (p = 0.03, CI: 1.2-13.2) and 2.6 (p = 0.02, CI: 1.2-5.5) for cardiovascular mortality and all-cause mortality, respectively. CONCLUSION: Heart transplant recipients with elevated resting HR appear to have higher mortality than those with lower resting HR. Whether pharmacologically lowering the HR would result in better outcomes warrants further investigation.


Assuntos
Transplante de Coração , Complicações Pós-Operatórias , Taquicardia/etiologia , Adulto , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Feminino , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/mortalidade , Transplante de Coração/mortalidade , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Taquicardia/diagnóstico , Taquicardia/mortalidade
6.
Circulation ; 127(4): 452-62, 2013 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-23271796

RESUMO

BACKGROUND: Survival of patients on left ventricular assist devices (LVADs) has improved. We examined the differences in risk of adverse outcomes between LVAD-supported and medically managed candidates on the heart transplant waiting list. METHODS AND RESULTS: We analyzed mortality and morbidity in 33,073 heart transplant candidates registered on the United Network for Organ Sharing (UNOS) waiting list between 1999 and 2011. Five groups were selected: patients without LVADs in urgency status 1A, 1B, and 2; patients with pulsatile-flow LVADs; and patients with continuous-flow LVADs. Outcomes in patients requiring biventricular assist devices, total artificial heart, and temporary VADs were also analyzed. Two eras were defined on the basis of the approval date of the first continuous-flow LVAD for bridge to transplantation in the United States (2008). Mortality was lower in the current compared with the first era (2.1%/mo versus 2.9%/mo; P<0.0001). In the first era, mortality of pulsatile-flow LVAD patients was higher than in status 2 (hazard ratio [HR], 2.15; P<0.0001) and similar to that in status 1B patients (HR, 1.04; P=0.61). In the current era, patients with continuous-flow LVADs had mortality similar to that of status 2 (HR, 0.80; P=0.12) and lower mortality compared with status 1A and 1B patients (HR, 0.24 and 0.47; P<0.0001 for both comparisons). However, status upgrade for LVAD-related complications occurred frequently (28%) and increased the mortality risk (HR, 1.75; P=0.001). Mortality was highest in patients with biventricular assist devices (HR, 5.00; P<0.0001) and temporary VADs (HR, 7.72; P<0.0001). CONCLUSIONS: Mortality and morbidity on the heart transplant waiting list have decreased. Candidates supported with contemporary continuous-flow LVADs have favorable waiting list outcomes; however, they worsen significantly once a serious LVAD-related complication occurs. Transplant candidates requiring temporary and biventricular support have the highest risk of adverse outcomes. These results may help to guide optimal allocation of donor hearts.


Assuntos
Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/cirurgia , Transplante de Coração/mortalidade , Coração Auxiliar/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adulto , Feminino , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Modelos de Riscos Proporcionais , Sistema de Registros/estatística & dados numéricos , Fatores de Risco , Estados Unidos/epidemiologia , Listas de Espera/mortalidade
7.
Appl Plant Sci ; 12(1): e11560, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38369981

RESUMO

Premise: Among the slowest steps in the digitization of natural history collections is converting imaged labels into digital text. We present here a working solution to overcome this long-recognized efficiency bottleneck that leverages synergies between community science efforts and machine learning approaches. Methods: We present two new semi-automated services. The first detects and classifies typewritten, handwritten, or mixed labels from herbarium sheets. The second uses a workflow tuned for specimen labels to label text using optical character recognition (OCR). The label finder and classifier was built via humans-in-the-loop processes that utilize the community science Notes from Nature platform to develop training and validation data sets to feed into a machine learning pipeline. Results: Our results showcase a >93% success rate for finding and classifying main labels. The OCR pipeline optimizes pre-processing, multiple OCR engines, and post-processing steps, including an alignment approach borrowed from molecular systematics. This pipeline yields >4-fold reductions in errors compared to off-the-shelf open-source solutions. The OCR workflow also allows human validation using a custom Notes from Nature tool. Discussion: Our work showcases a usable set of tools for herbarium digitization including a custom-built web application that is freely accessible. Further work to better integrate these services into existing toolkits can support broad community use.

8.
PLoS One ; 19(3): e0300111, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38470891

RESUMO

Better understanding how organisms respond to their abiotic environment, especially at the biochemical level, is critical in predicting population trajectories under climate change. In this study, we measured constitutive stress biomarkers and protein post-translational modifications associated with oxidative stress in Gallotia galloti, an insular lizard species inhabiting highly heterogeneous environments on Tenerife. Tenerife is a small volcanic island in a relatively isolated archipelago off the West coast of Africa. We found that expression of GRP94, a molecular chaperone protein, and levels of protein carbonylation, a marker of cellular stress, change across different environments, depending on solar radiation-related variables and topology. Here, we report in a wild animal population, cross-talk between the baseline levels of the heat shock protein-like GRP94 and oxidative damage (protein carbonylation), which are influenced by a range of available temperatures, quantified through modelled operative temperature. This suggests a dynamic trade-off between cellular homeostasis and oxidative damage in lizards adapted to this thermally and topologically heterogeneous environment.


Assuntos
Proteínas de Choque Térmico , Lagartos , Animais , Estresse Oxidativo , Processamento de Proteína Pós-Traducional , Carbonilação Proteica
9.
Cancers (Basel) ; 16(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38927877

RESUMO

Cancer cells show altered antioxidant defense systems, dysregulated redox signaling, and increased generation of reactive oxygen species (ROS). Targeting cancer cells through ROS-mediated mechanisms has emerged as a significant therapeutic strategy due to its implications in cancer progression, survival, and resistance. Extensive research has focused on selective generation of H2O2 in cancer cells for selective cancer cell killing by employing various strategies such as metal-based prodrugs, photodynamic therapy, enzyme-based systems, nano-particle mediated approaches, chemical modulators, and combination therapies. Many of these H2O2-amplifying approaches have demonstrated promising anticancer effects and selectivity in preclinical investigations. They selectively induce cytotoxicity in cancer cells while sparing normal cells, sensitize resistant cells, and modulate the tumor microenvironment. However, challenges remain in achieving selectivity, addressing tumor heterogeneity, ensuring efficient delivery, and managing safety and toxicity. To address those issues, H2O2-generating agents have been combined with other treatments leading to optimized combination therapies. This review focuses on various chemical agents/approaches that kill cancer cells via H2O2-mediated mechanisms. Different categories of compounds that selectively generate H2O2 in cancer cells are summarized, their underlying mechanisms and function are elucidated, preclinical and clinical studies as well as recent advancements are discussed, and their prospects as targeted therapeutic agents and their therapeutic utility in combination with other treatments are explored. By understanding the potential of these compounds, researchers can pave the way for the development of effective and personalized cancer treatments.

10.
bioRxiv ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39005434

RESUMO

Amphibians represent a diverse group of tetrapods, marked by deep divergence times between their three systematic orders and families. Studying amphibian biology through the genomics lens increases our understanding of the features of this animal class and that of other terrestrial vertebrates. The need for amphibian genomics resources is more urgent than ever due to the increasing threats to this group. Amphibians are one of the most imperiled taxonomic groups, with approximately 41% of species threatened with extinction due to habitat loss, changes in land use patterns, disease, climate change, and their synergistic effects. Amphibian genomics resources have provided a better understanding of ontogenetic diversity, tissue regeneration, diverse life history and reproductive modes, antipredator strategies, and resilience and adaptive responses. They also serve as critical models for understanding widespread genomic characteristics, including evolutionary genome expansions and contractions given they have the largest range in genome sizes of any animal taxon and multiple mechanisms of genetic sex determination. Despite these features, genome sequencing of amphibians has significantly lagged behind that of other vertebrates, primarily due to the challenges of assembling their large, repeat-rich genomes and the relative lack of societal support. The advent of long-read sequencing technologies, along with computational techniques that enhance scaffolding capabilities and streamline computational workload is now enabling the ability to overcome some of these challenges. To promote and accelerate the production and use of amphibian genomics research through international coordination and collaboration, we launched the Amphibian Genomics Consortium (AGC) in early 2023. This burgeoning community already has more than 282 members from 41 countries (6 in Africa, 131 in the Americas, 27 in Asia, 29 in Australasia, and 89 in Europe). The AGC aims to leverage the diverse capabilities of its members to advance genomic resources for amphibians and bridge the implementation gap between biologists, bioinformaticians, and conservation practitioners. Here we evaluate the state of the field of amphibian genomics, highlight previous studies, present challenges to overcome, and outline how the AGC can enable amphibian genomics research to "leap" to the next level.

11.
Database (Oxford) ; 20232023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37465916

RESUMO

How should billions of species observations worldwide be shared and made reusable? Many biodiversity scientists assume the ideal solution is to standardize all datasets according to a single, universal classification and aggregate them into a centralized, global repository. This ideal has known practical and theoretical limitations, however, which justifies investigating alternatives. To support better community deliberation and normative evaluation, we develop a novel conceptual framework showing how different organizational models, regulative ideals and heuristic strategies are combined to form shared infrastructures supporting data reuse. The framework is anchored in a general definition of data pooling as an activity of making a taxonomically standardized body of information available for community reuse via digital infrastructure. We describe and illustrate unified and pluralistic ideals for biodiversity data pooling and show how communities may advance toward these ideals using different heuristic strategies. We present evidence for the strengths and limitations of the unification and pluralistic ideals based on systemic relationships of power, responsibility and benefit they establish among stakeholders, and we conclude the pluralistic ideal is better suited for biodiversity data.


Assuntos
Biodiversidade , Disseminação de Informação
12.
Cardiology ; 122(2): 104-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22759389

RESUMO

ß-Adrenergic receptors (ß-AR) are central to the overall regulation of cardiac function. From the first proposed receptor/transmitter concept to the latest clinical ß-blocker trials ß-AR have been shown to play an important role in cardiac disease and heart failure in particular. This study provides a historical perspective, reviews the latest discoveries and beliefs, and discusses the current clinical practices of ß-AR and their modulation with their associated guanine-nucleotide regulatory protein/adenylylcyclasesignal transduction pathways.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Receptores Adrenérgicos beta/fisiologia , Antagonistas Adrenérgicos beta/uso terapêutico , Proteínas de Ligação ao GTP/fisiologia , Insuficiência Cardíaca/etiologia , História do Século XX , Humanos , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Receptores Adrenérgicos beta/classificação , Receptores Adrenérgicos beta/história , Transdução de Sinais/fisiologia
13.
Transplant Proc ; 54(1): 193-196, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35012763

RESUMO

Checkpoint inhibitors decrease the progression of many cancers. However, the experience in immunosuppressed patients is limited, with reports of possible serious adverse events. We present a heart transplant recipient treated with pembrolizumab for metastatic melanoma who developed fatal rejection. The patient was a 29 year-old man who underwent heart transplantation at the age of 10 years for congenital heart disease. Seventeen years after transplant, he was diagnosed with scalp melanoma pT3a, N2a, M0, Stage IIIA, positive for BRAF V600E mutation treated with excision, which metastasized to his lungs and brain a year later. Dabrafenib and trametinib were started with transient response. Additional options and their risks were discussed, and pembrolizumab was started 4 months later due to the incomplete response to previous therapy. Five days after initiation the patient presented with moderate cellular rejection and possible antibody mediated rejection (ISHLT Grade 2R, pAMR 1H). Pembrolizumab was discontinued, and he was treated with steroids. Seven months later he presented in cardiogenic shock and severe coronary allograft vasculopathy. Biopsy was negative for cellular rejection, but suspicious for antibody mediated rejection (ISHLT Grade 0R, pAMR 1H), and he had a new serum alloantibody. Despite steroids and plasmapheresis he remained in refractory cardiogenic shock and died of cardiac arrest.


Assuntos
Transplante de Coração , Melanoma , Adulto , Aloenxertos , Anticorpos Monoclonais Humanizados , Criança , Rejeição de Enxerto , Transplante de Coração/efeitos adversos , Humanos , Masculino , Melanoma/tratamento farmacológico
14.
Circ Heart Fail ; 15(6): e008706, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35658464

RESUMO

BACKGROUND: Our current understanding of right heart failure (RHF) post-left ventricular assist device (LVAD) is lacking. Recently, a new Interagency Registry for Mechanically Assisted Circulatory Support definition of RHF was introduced. Based on this definition, we investigated natural history, risk factors, and outcomes of post-LVAD RHF. METHODS: Patients implanted with continuous flow LVAD between June 2, 2014, and June 30, 2016 and registered in the Interagency Registry for Mechanically Assisted Circulatory Support/Society of Thoracic Surgeons Database were included. RHF incidence and predictors, and survival after RHF were assessed. The manifestations of RHF which were separately analyzed were elevated central venous pressure, peripheral edema, ascites, and use of inotropes. RESULTS: Among 5537 LVAD recipients (mean 57±13 years, 49% destination therapy, support 18.9 months) prevalence of 1-month RHF was 24%. Of these, RHF persisted at 12 months in 5.3%. In contrast, de novo RHF, first identified at 3 months, occurred in 5.1% and persisted at 12 months in 17% of these, and at 6 months occurred in 4.8% and persisted at 12 months in 25%. Higher preimplant blood urea nitrogen (ORs,1.03-1.09 per 5 mg/dL increase; P<0.0001), previous tricuspid valve repair/replacement (ORs, 2.01-10.09; P<0.001), severely depressed right ventricular systolic function (ORs,1.17-2.20; P=0.004); and centrifugal versus axial LVAD (ORs,1.15-1.78; P=0.001) represented risk factors for RHC incidence at 3 months. Patients with persistent RHF at 3 months had the lowest 2-year survival (57%) while patients with de novo RHF or RHF which resolved by 3 months had more favorable survival outcomes (75% and 78% at 2 years, respectively; P<0.001). CONCLUSIONS: RHF at 1 or 3 months post-LVAD was a common and frequently transient condition, which, if resolved, was associated with relatively favorable prognosis. Conversely, de novo, late RHF post-LVAD (>6 months) was more frequently a persistent disorder and associated with increased mortality. The 1-, 3-, and 6-month time points may be used for RHF assessment and risk stratification in LVAD recipients.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Ventrículos do Coração/diagnóstico por imagem , Coração Auxiliar/efeitos adversos , Humanos , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
15.
JAMA Cardiol ; 6(8): 957-962, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33950162

RESUMO

Importance: Heart failure with recovered ejection fraction (HFrecEF) is a recently recognized phenotype of patients with a history of reduced left ventricular ejection fraction (LVEF) that has subsequently normalized. It is unknown whether such LVEF improvement is associated with improvements in health status. Objective: To examine changes in health-related quality of life in patients with heart failure with reduced ejection fraction (HFrEF) whose LVEF normalized, compared with those whose LVEF remains reduced and those with HF with preserved EF (HFpEF). Design, Setting, and Participants: This prospective cohort study was conducted at a tertiary care hospital from November 2016 to December 2018. Consecutive patients seen in a heart failure clinic who completed patient-reported outcome assessments were included. Clinical data were abstracted from the electronic health record. Data analysis was completed from February to December 2020. Main Outcomes and Measures: Changes in Kansas City Cardiomyopathy Questionnaire overall summary score, Visual Analog Scale score, and Patient-Reported Outcomes Measurement Information System domain scores on physical function, fatigue, depression, and satisfaction with social roles over 1-year follow-up. Results: The study group included 319 patients (mean [SD] age, 60.4 [15.5] years; 120 women [37.6%]). At baseline, 212 patients (66.5%) had HFrEF and 107 (33.5%) had HFpEF. At a median follow-up of 366 (interquartile range, 310-421) days, LVEF had increased to 50% or more in 35 patients with HFrEF (16.5%). Recovery of systolic function was associated with heart failure-associated quality-of-life improvement, such that for each 10% increase in LVEF, the Kansas City Cardiomyopathy Questionnaire score improved by an mean (SD) of 4.8 (1.6) points (P = .003). Recovery of LVEF was also associated with improvement of physical function, satisfaction with social roles, and a reduction in fatigue. Conclusions and Relevance: Among patients with HFrEF in this study, normalization of left ventricular systolic function was associated with a significant improvement in health-related quality of life.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Qualidade de Vida , Recuperação de Função Fisiológica/fisiologia , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos
16.
Nat Plants ; 7(8): 1010-1014, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34326529

RESUMO

Field photographs of plant species are crucial for research and conservation, but the lack of a centralized database makes them difficult to locate. We surveyed 25 online databases of field photographs and found that they harboured only about 53% of the approximately 125,000 vascular plant species of the Americas. These results reflect the urgent need for a centralized database that can both integrate and complete the photographic record of the world's flora.


Assuntos
Biodiversidade , Bases de Dados Factuais/estatística & dados numéricos , Geografia/estatística & dados numéricos , Fotografação/estatística & dados numéricos , Plantas , América
17.
Am J Physiol Heart Circ Physiol ; 299(5): H1653-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20833963

RESUMO

To better characterize the contribution of both central and peripheral mechanisms to passive limb movement-induced hyperemia, we studied nine recent (<2 yr) heart transplant (HTx) recipients (56 ± 4 yr) and nine healthy controls (58 ± 5 yr). Measurements of heart rate (HR), stroke volume (SV), cardiac output (CO), and femoral artery blood flow were recorded during passive knee extension. Peripheral vascular function was assessed using brachial artery flow-mediated dilation (FMD). During passive limb movement, the HTx recipients lacked an HR response (0 ± 0 beats/min, Δ0%) but displayed a significant increase in CO (0.4 ± 0.1 l/min, Δ5%) although attenuated compared with controls (1.0 ± 0.2 l/min, Δ18%). Therefore, the rise in CO in the HTx recipients was solely dependent on increased SV (5 ± 1 ml, Δ5%) in contrast with the controls who displayed significant increases in both HR (6 ± 2 beats/min, Δ11%) and SV (5 ± 2 ml, Δ7%). The transient increase in femoral blood volume entering the leg during the first 40 s of passive movement was attenuated in the HTx recipients (24 ± 8 ml) compared with controls (93 ± 7 ml), whereas peripheral vascular function (FMD) appeared similar between HTx recipients (8 ± 2%) and controls (6 ± 1%). These data reveal that the absence of an HR increase in HTx recipients significantly impacts the peripheral vascular response to passive movement in this population and supports the concept that an increase in CO is a major contributor to exercise-induced hyperemia.


Assuntos
Exercício Físico/fisiologia , Artéria Femoral/fisiologia , Frequência Cardíaca/fisiologia , Transplante de Coração/fisiologia , Hiperemia/fisiopatologia , Perna (Membro)/irrigação sanguínea , Fluxo Sanguíneo Regional/fisiologia , Volume Sanguíneo/fisiologia , Monóxido de Carbono/metabolismo , Débito Cardíaco/fisiologia , Estudos de Casos e Controles , Feminino , Hemodinâmica/fisiologia , Humanos , Perna (Membro)/fisiologia , Masculino , Pessoa de Meia-Idade , Volume Sistólico/fisiologia
18.
Front Big Data ; 3: 519133, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33693407

RESUMO

Centralized biodiversity data aggregation is too often failing societal needs due to pervasive and systemic data quality deficiencies. We argue for a novel approach that embodies the spirit of the Web ("small pieces loosely joined") through the decentralized coordination of data across scientific languages and communities. The upfront cost of decentralization can be offset by the long-term benefit of achieving sustained expert engagement, higher-quality data products, and ultimately more societal impact for biodiversity data. Our decentralized approach encourages the emergence and evolution of multiple self-identifying communities of practice that are regionally, taxonomically, or institutionally localized. Each community is empowered to control the social and informational design and versioning of their local data infrastructures and signals. With no single aggregator to exert centralized control over biodiversity data, decentralization generates loosely connected networks of mid-level aggregators. Global coordination is nevertheless feasible through automatable data sharing agreements that enable efficient propagation and translation of biodiversity data across communities. The decentralized model also poses novel integration challenges, among which the explicit and continuous articulation of conflicting systematic classifications and phylogenies remain the most challenging. We discuss the development of available solutions, challenges, and outline next steps: the global effort of coordination should focus on developing shared languages for data signal translation, as opposed to homogenizing the data signal itself.

19.
JACC Heart Fail ; 8(4): 302-312, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32241537

RESUMO

OBJECTIVES: The aim of this study was to evaluate the impact of a shared-care model on outcomes in patients with left ventricular assist devices (LVADs) living in remote locations. BACKGROUND: Health care delivery through shared-care models has been shown to improve outcomes in patients with chronic diseases. However, the impact of shared-care models on outcomes in patients with LVAD is unknown. METHODS: LVAD recipients in the authors' program (2007 to 2018) were classified based on the levels of care provided and training and resources used: level 1, was defined as outpatient primary care without LVAD-specific care; level 2 was level 1 services and outpatient LVAD-specific care; level 3 was level 2 services and inpatient LVAD-specific care and implantation center (IC). The Kaplan-Meier method was used to compare rates of survival, bleeding, pump thrombosis, infection, neurologic events, and readmissions among levels of care. RESULTS: A total of 336 patients were included, with 255 patients (75.9%) cared for in shared-care facilities. Median follow-up was 810 (interquartile range: 321 to 1,096) days. In comparison to patients cared for by IC, patients at levels 2 and 3 shared-care centers had similar rates of death, bleeding, neurologic events, pump thromboses, and infections. However, the rates of death, pump thromboses, and infections were higher for level 1 patients than in IC patients. CONCLUSIONS: Shared health care is an effective strategy to deliver care to patients with LVAD living in remote locations. However, patients in shared-care facilities unable to provide LVAD-specific care are at higher risk of unfavorable outcomes. Availability of LVAD-specific care should be strongly considered during patient selection and every effort made to ensure LVAD-specific training and resources are available at shared-care facilities.


Assuntos
Atenção à Saúde/métodos , Insuficiência Cardíaca/terapia , Ventrículos do Coração/fisiopatologia , Coração Auxiliar , Qualidade de Vida , Função Ventricular Esquerda/fisiologia , Idoso , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
20.
JACC Basic Transl Sci ; 5(9): 871-883, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32838074

RESUMO

Using serial analysis of myocardial gene expression employing endomyocardial biopsy starting material in a dilated cardiomyopathy cohort, we show that mRNA expression of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) cardiac myocyte receptor ACE2 is up-regulated with remodeling and with reverse remodeling down-regulates into the normal range. The proteases responsible for virus-cell membrane fusion were expressed but not regulated with remodeling. In addition, a new candidate for SARS-CoV-2 cell binding and entry was identified, the integrin encoded by ITGA5. Up-regulation in ACE2 in remodeled left ventricles may explain worse outcomes in patients with coronavirus disease 2019 who have underlying myocardial disorders, and counteracting ACE2 up-regulation is a possible therapeutic approach to minimizing cardiac damage.

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