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1.
Mol Cell ; 81(7): 1484-1498.e6, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33561389

RESUMO

Transcription factors (TFs) regulate gene expression by binding to specific consensus motifs within the local chromatin context. The mechanisms by which TFs navigate the nuclear environment as they search for binding sites remain unclear. Here, we used single-molecule tracking and machine-learning-based classification to directly measure the nuclear mobility of the glucocorticoid receptor (GR) in live cells. We revealed two distinct and dynamic low-mobility populations. One accounts for specific binding to chromatin, while the other represents a confinement state that requires an intrinsically disordered region (IDR), implicated in liquid-liquid condensate subdomains. Further analysis showed that the dwell times of both subpopulations follow a power-law distribution, consistent with a broad distribution of affinities on the GR cistrome and interactome. Together, our data link IDRs with a confinement state that is functionally distinct from specific chromatin binding and modulates the transcriptional output by increasing the local concentration of TFs at specific sites.


Assuntos
Proteínas Intrinsicamente Desordenadas/química , Receptores de Glucocorticoides/química , Fatores de Transcrição/química , Animais , Feminino , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Camundongos , Ratos , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Mol Cell ; 75(6): 1161-1177.e11, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31421980

RESUMO

Genes are transcribed in a discontinuous pattern referred to as RNA bursting, but the mechanisms regulating this process are unclear. Although many physiological signals, including glucocorticoid hormones, are pulsatile, the effects of transient stimulation on bursting are unknown. Here we characterize RNA synthesis from single-copy glucocorticoid receptor (GR)-regulated transcription sites (TSs) under pulsed (ultradian) and constant hormone stimulation. In contrast to constant stimulation, pulsed stimulation induces restricted bursting centered around the hormonal pulse. Moreover, we demonstrate that transcription factor (TF) nuclear mobility determines burst duration, whereas its bound fraction determines burst frequency. Using 3D tracking of TSs, we directly correlate TF binding and RNA synthesis at a specific promoter. Finally, we uncover a striking co-bursting pattern between TSs located at proximal and distal positions in the nucleus. Together, our data reveal a dynamic interplay between TF mobility and RNA bursting that is responsive to stimuli strength, type, modality, and duration.


Assuntos
Glucocorticoides/farmacologia , Regiões Promotoras Genéticas , RNA/biossíntese , Receptores de Glucocorticoides/metabolismo , Sítio de Iniciação de Transcrição , Transcrição Gênica/efeitos dos fármacos , Animais , Camundongos , RNA/genética
3.
Cell ; 145(4): 571-83, 2011 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-21565614

RESUMO

The molecular basis for p53-mediated tumor suppression remains unclear. Here, to elucidate mechanisms of p53 tumor suppression, we use knockin mice expressing an allelic series of p53 transcriptional activation mutants. Microarray analysis reveals that one mutant, p53(25,26), is severely compromised for transactivation of most p53 target genes, and, moreover, p53(25,26) cannot induce G(1)-arrest or apoptosis in response to acute DNA damage. Surprisingly, p53(25,26) retains robust activity in senescence and tumor suppression, indicating that efficient transactivation of the majority of known p53 targets is dispensable for these pathways. In contrast, the transactivation-dead p53(25,26,53,54) mutant cannot induce senescence or inhibit tumorigenesis, like p53 nullizygosity. Thus, p53 transactivation is essential for tumor suppression but, intriguingly, in association with a small set of novel p53 target genes. Together, our studies distinguish the p53 transcriptional programs involved in acute DNA-damage responses and tumor suppression-a critical goal for designing therapeutics that block p53-dependent side effects of chemotherapy without compromising p53 tumor suppression.


Assuntos
Reparo do DNA , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , Ciclo Celular , Senescência Celular , Dano ao DNA , Técnicas de Introdução de Genes , Humanos , Camundongos , Mutação , Neoplasias/metabolismo , Estrutura Terciária de Proteína , Ativação Transcricional , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética
4.
Cell ; 146(4): 544-54, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21835447

RESUMO

The glucocorticoid receptor (GR), like other eukaryotic transcription factors, regulates gene expression by interacting with chromatinized DNA response elements. Photobleaching experiments in living cells indicate that receptors transiently interact with DNA on the time scale of seconds and predict that the response elements may be sparsely occupied on average. Here, we show that the binding of one receptor at the glucocorticoid response element (GRE) does not reduce the steady-state binding of another receptor variant to the same GRE. Mathematical simulations reproduce this noncompetitive state using short GR/GRE residency times and relatively long times between DNA binding events. At many genomic sites where GR binding causes increased chromatin accessibility, concurrent steady-state binding levels for the variant receptor are actually increased, a phenomenon termed assisted loading. Temporally sparse transcription factor-DNA interactions induce local chromatin reorganization, resulting in transient access for binding of secondary regulatory factors.


Assuntos
Montagem e Desmontagem da Cromatina , Receptores de Glucocorticoides/metabolismo , Elementos de Resposta , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Vírus do Tumor Mamário do Camundongo , Camundongos , Modelos Biológicos , Método de Monte Carlo , Nucleossomos/metabolismo , Receptores de Estrogênio/metabolismo , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/metabolismo
5.
Circulation ; 150(8): 586-597, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38742491

RESUMO

BACKGROUND: Diffuse coronary artery disease affects the safety and efficacy of percutaneous coronary intervention (PCI). Pathophysiologic coronary artery disease patterns can be quantified using fractional flow reserve (FFR) pullbacks incorporating the pullback pressure gradient (PPG) calculation. This study aimed to establish the capacity of PPG to predict optimal revascularization and procedural outcomes. METHODS: This prospective, investigator-initiated, single-arm, multicenter study enrolled patients with at least one epicardial lesion with an FFR ≤0.80 scheduled for PCI. Manual FFR pullbacks were used to calculate PPG. The primary outcome of optimal revascularization was defined as an FFR ≥0.88 after PCI. RESULTS: A total of 993 patients with 1044 vessels were included. The mean FFR was 0.68±0.12, PPG 0.62±0.17, and the post-PCI FFR was 0.87±0.07. PPG was significantly correlated with the change in FFR after PCI (r=0.65 [95% CI, 0.61-0.69]; P<0.001) and demonstrated excellent predictive capacity for optimal revascularization (area under the receiver operating characteristic curve, 0.82 [95% CI, 0.79-0.84]; P<0.001). FFR alone did not predict revascularization outcomes (area under the receiver operating characteristic curve, 0.54 [95% CI, 0.50-0.57]). PPG influenced treatment decisions in 14% of patients, redirecting them from PCI to alternative treatment modalities. Periprocedural myocardial infarction occurred more frequently in patients with low PPG (<0.62) compared with those with focal disease (odds ratio, 1.71 [95% CI, 1.00-2.97]). CONCLUSIONS: Pathophysiologic coronary artery disease patterns distinctly affect the safety and effectiveness of PCI. PPG showed an excellent predictive capacity for optimal revascularization and demonstrated added value compared with an FFR measurement. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04789317.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/terapia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
6.
Proc Natl Acad Sci U S A ; 119(15): e2119429119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377791

RESUMO

Charge density waves (CDWs) have been observed in nearly all families of copper-oxide superconductors. But the behavior of these phases across different families has been perplexing. In La-based cuprates, the CDW wavevector is an increasing function of doping, exhibiting the so-called Yamada behavior, while in Y- and Bi-based materials the behavior is the opposite. Here, we report a combined resonant soft X-ray scattering (RSXS) and neutron scattering study of charge and spin density waves in isotopically enriched La1.8−xEu0.2SrxCuO4 over a range of doping 0.07≤x≤0.20. We find that the CDW amplitude is temperature independent and develops well above experimentally accessible temperatures. Further, the CDW wavevector shows a nonmonotonic temperature dependence, exhibiting Yamada behavior at low temperature with a sudden change occurring near the spin ordering temperature. We describe these observations using a Landau­Ginzburg theory for an incommensurate CDW in a metallic system with a finite charge compressibility and spin-CDW coupling. Extrapolating to high temperature, where the CDW amplitude is small and spin order is absent, our analysis predicts a decreasing wavevector with doping, similar to Y and Bi cuprates. Our study suggests that CDW order in all families of cuprates forms by a common mechanism.

7.
Ophthalmology ; 131(2): 179-187, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37709170

RESUMO

PURPOSE: To determine early endophthalmitis incidence and risk factors after glaucoma surgeries in the Medicare population. DESIGN: Retrospective, longitudinal study. PARTICIPANTS: Medicare Fee-for-Service (FFS) and Medicare Advantage beneficiaries in the United States aged 65 years or older undergoing glaucoma surgery. METHODS: Medicare claims were used to identify all patients who underwent glaucoma, cataract, or combined cataract/glaucoma surgery from 2016 to 2019. Endophthalmitis cases within 42 days of the index surgery were identified using the diagnostic codes. Multivariable logistic regression models were used to evaluate factors associated with postoperative endophthalmitis. MAIN OUTCOME MEASURES: The 42-day postoperative endophthalmitis incidence and risk factors associated with endophthalmitis after glaucoma surgery. RESULTS: There were 466 928 glaucoma surgeries, of which 310 823 (66.6%) were combined with cataract surgery. Cataract surgeries alone (n = 8 460 360) served as a reference group. Microinvasive glaucoma surgeries constituted most glaucoma procedures performed (67.8%), followed by trabeculectomy (14.0%), tube shunt (10.9%), and other procedures (7.3%). There were 572 cases of endophthalmitis identified after all glaucoma surgeries. Endophthalmitis incidence after glaucoma, combined cataract/glaucoma, and cataract surgeries alone was 1.5 (95% confidence interval [CI], 1.3-1.7), 1.1 (95% CI, 1.0-1.2), and 0.8 (95% CI, 0.8-0.8) per 1000 procedures, respectively. The median day of diagnosis of endophthalmitis was later for glaucoma surgeries (16.5 days) compared with combined cataract/glaucoma or cataract surgeries alone (8 and 6 days, respectively). Compared with microinvasive glaucoma surgery (MIGS), tube shunts were the only surgery type to be a significant risk factor for endophthalmitis for both stand-alone (adjusted odds ratio [aOR], 1.8, P = 0.002) and combined surgery (aOR 1.8, P = 0.047). The other risk factor for both stand-alone (aOR 1.1, P = 0.001) and combined (aOR 1.06, P = 0.049) surgeries was the Charlson Comorbidity Index (CCI). Age (aOR 1.03, P = 0.004) and male gender (1.46, P = 0.001) were significant risk factors for combined cataract and glaucoma surgeries. CONCLUSIONS: Compared with cataract surgery, early endophthalmitis incidence was higher for both glaucoma and combined cataract/glaucoma surgeries, with the highest incidence among tube shunts. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Assuntos
Extração de Catarata , Catarata , Endoftalmite , Glaucoma , Humanos , Idoso , Masculino , Estados Unidos/epidemiologia , Medicare , Estudos Retrospectivos , Incidência , Estudos Longitudinais , Endoftalmite/epidemiologia , Endoftalmite/etiologia , Endoftalmite/diagnóstico , Extração de Catarata/efeitos adversos , Fatores de Risco , Catarata/complicações , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Glaucoma/epidemiologia , Glaucoma/cirurgia , Glaucoma/complicações
8.
Brain Behav Immun ; 115: 718-726, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995835

RESUMO

Aberrant cortical development is a key feature of neurodevelopmental disorders such as autism spectrum disorder and schizophrenia. Both genetic and environmental risk factors are thought to contribute to defects in cortical development; however, model systems that can capture the dynamic process of human cortical development are not well established. To address this challenge, we combined recent progress in induced pluripotent stem cell differentiation with advanced live cell imaging techniques to establish a novel three-dimensional neurosphere assay, amenable to genetic and environmental modifications, to investigate key aspects of human cortical development in real-time. For the first time, we demonstrate the ability to visualise and quantify radial glial extension and neural migration through live cell imaging. To show proof-of-concept, we used our neurosphere assay to study the effect of a simulated viral infection, a well-established environmental risk factor in neurodevelopmental disorders, on cortical development. This was achieved by exposing neurospheres to the viral mimic, polyinosinic:polycytidylic acid. The results showed significant reductions in radial glia growth and neural migration in three independent differentiations. Further, fixed imaging highlighted reductions in the HOPX-expressing outer radial glia scaffolding and a consequent decrease in the migration of CTIP2-expressing cortical cells. Overall, our results provide new insight into how infections may exert deleterious effects on the developing human cortex.


Assuntos
Transtorno do Espectro Autista , Células-Tronco Pluripotentes Induzidas , Viroses , Humanos , Neurogênese , Diferenciação Celular
9.
Biotechnol Bioeng ; 121(2): 618-639, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37947118

RESUMO

The recent uptick in the approval of ex vivo cell therapies highlights the relevance of lentivirus (LV) as an enabling viral vector of modern medicine. As labile biologics, however, LVs pose critical challenges to industrial biomanufacturing. In particular, LV purification-currently reliant on filtration and anion-exchange or size-exclusion chromatography-suffers from long process times and low yield of transducing particles, which translate into high waiting time and cost to patients. Seeking to improve LV downstream processing, this study introduces peptides targeting the enveloped protein Vesicular stomatitis virus G (VSV-G) to serve as affinity ligands for the chromatographic purification of LV particles. An ensemble of candidate ligands was initially discovered by implementing a dual-fluorescence screening technology and a targeted in silico approach designed to identify sequences with high selectivity and tunable affinity. The selected peptides were conjugated on Poros resin and their LV binding-and-release performance was optimized by adjusting the flow rate, composition, and pH of the chromatographic buffers. Ligands GKEAAFAA and SRAFVGDADRD were selected for their high product yield (50%-60% of viral genomes; 40%-50% of HT1080 cell-transducing particles) upon elution in PIPES buffer with 0.65 M NaCl at pH 7.4. The peptide-based adsorbents also presented remarkable values of binding capacity (up to 3·109 TU per mL of resin, or 5·1011 vp per mL of resin, at the residence time of 1 min) and clearance of host cell proteins (up to a 220-fold reduction of HEK293 HCPs). Additionally, GKEAAFAA demonstrated high resistance to caustic cleaning-in-place (0.5 M NaOH, 30 min) with no observable loss in product yield and quality.


Assuntos
Lentivirus , Estomatite Vesicular , Animais , Humanos , Lentivirus/genética , Lentivirus/metabolismo , Células HEK293 , Peptídeos/metabolismo , Vesiculovirus/genética , Vetores Genéticos
10.
BMC Cardiovasc Disord ; 24(1): 343, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969974

RESUMO

BACKGROUND: Heart failure (HF) with preserved or mildly reduced ejection fraction includes a heterogenous group of patients. Reclassification into distinct phenogroups to enable targeted interventions is a priority. This study aimed to identify distinct phenogroups, and compare phenogroup characteristics and outcomes, from electronic health record data. METHODS: 2,187 patients admitted to five UK hospitals with a diagnosis of HF and a left ventricular ejection fraction ≥ 40% were identified from the NIHR Health Informatics Collaborative database. Partition-based, model-based, and density-based machine learning clustering techniques were applied. Cox Proportional Hazards and Fine-Gray competing risks models were used to compare outcomes (all-cause mortality and hospitalisation for HF) across phenogroups. RESULTS: Three phenogroups were identified: (1) Younger, predominantly female patients with high prevalence of cardiometabolic and coronary disease; (2) More frail patients, with higher rates of lung disease and atrial fibrillation; (3) Patients characterised by systemic inflammation and high rates of diabetes and renal dysfunction. Survival profiles were distinct, with an increasing risk of all-cause mortality from phenogroups 1 to 3 (p < 0.001). Phenogroup membership significantly improved survival prediction compared to conventional factors. Phenogroups were not predictive of hospitalisation for HF. CONCLUSIONS: Applying unsupervised machine learning to routinely collected electronic health record data identified phenogroups with distinct clinical characteristics and unique survival profiles.


Assuntos
Registros Eletrônicos de Saúde , Insuficiência Cardíaca , Volume Sistólico , Função Ventricular Esquerda , Humanos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Medição de Risco , Reino Unido/epidemiologia , Fatores de Risco , Prognóstico , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Aprendizado de Máquina não Supervisionado , Hospitalização , Fatores de Tempo , Comorbidade , Causas de Morte , Fenótipo , Mineração de Dados
11.
Arch Sex Behav ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256237

RESUMO

We describe here the sexual histories and characteristics of 338 individuals with interests in castration (orchiectomy) and, more broadly, genital ablation (i.e., orchiectomy, penectomy, and/or nullification), recruited from the Eunuch Archive. We compared four groups: those who only fantasize about castration (Fantasy, n = 66), those who wish to be castrated in the future (Aspiring, n = 166), and those who have been castrated (Eunuchs) both with (n = 42) or without (n = 64) androgen replacement therapy (ART). In our sample, 35.6-53.8% had sexual fantasies of castrating someone, 83.3-90.8% had fantasies of being castrated, 20.6-33.3% had fantasies of removing someone's penis, and 45.3-61.9% had fantasies of having a penectomy. The four groups had similar arousal by high-risk sex behaviors, anal sex play, attraction to people under 18, common sex behaviors, and fetishistic behaviors. Fantasy of being castrated by someone was associated with elevated high-risk sexual behaviors and attraction to individuals aged 18 to 49 after controlling for age, groups, and sexual attraction. In addition, after adjusting for age, groups, and sexual attraction, fantasy of castrating someone was associated with more attraction to individuals under the age of 18 and being aroused by interaction with a stranger, whereas fantasy of cutting off someone's penis was associated with less tendency for common sexual behaviors and digital sex communication. Fantasy of being penectomized was associated with high risk and fetishistic sexual behaviors. These results support screening for high-risk behaviors in individuals who endorse an interest in genital ablation, with treatments focused on harm reduction.

12.
Nucleic Acids Res ; 50(22): 13063-13082, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36464162

RESUMO

The glucocorticoid receptor (GR) is a ubiquitously expressed transcription factor that controls metabolic and homeostatic processes essential for life. Although numerous crystal structures of the GR ligand-binding domain (GR-LBD) have been reported, the functional oligomeric state of the full-length receptor, which is essential for its transcriptional activity, remains disputed. Here we present five new crystal structures of agonist-bound GR-LBD, along with a thorough analysis of previous structural work. We identify four distinct homodimerization interfaces on the GR-LBD surface, which can associate into 20 topologically different homodimers. Biologically relevant homodimers were identified by studying a battery of GR point mutants including crosslinking assays in solution, quantitative fluorescence microscopy in living cells, and transcriptomic analyses. Our results highlight the relevance of non-canonical dimerization modes for GR, especially of contacts made by loop L1-3 residues such as Tyr545. Our work illustrates the unique flexibility of GR's LBD and suggests different dimeric conformations within cells. In addition, we unveil pathophysiologically relevant quaternary assemblies of the receptor with important implications for glucocorticoid action and drug design.


Assuntos
Glucocorticoides , Receptores de Glucocorticoides , Receptores de Glucocorticoides/metabolismo , Ligantes , Ligação Proteica , Dimerização
13.
Ophthalmic Plast Reconstr Surg ; 40(1): e14-e16, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38241629

RESUMO

Orbital abscesses are rarely encountered in children younger than 1 year. The literature is limited to isolated case reports and a few case series. Most such cases are reported in infants born at term, with the earliest reported gestational birth age at 34 weeks. Children are more prone to orbital cellulitis compared with adults due to their underdeveloped sinuses and immature immune systems, and the origin is most commonly an ethmoid sinus infection. Orbital cellulitis secondary to dacryocystitis is even less common, with only a few isolated cases reported in infants and children. Herein, the authors present a case of a large extraconal and intraconal orbital abscess secondary to nasolacrimal duct obstruction and dacryocystitis in an extremely preterm infant. We discuss the diagnosis and multidisciplinary management of this challenging case.


Assuntos
Dacriocistite , Dacriocistorinostomia , Obstrução dos Ductos Lacrimais , Ducto Nasolacrimal , Celulite Orbitária , Lactente , Adulto , Criança , Humanos , Recém-Nascido , Obstrução dos Ductos Lacrimais/diagnóstico , Obstrução dos Ductos Lacrimais/etiologia , Celulite Orbitária/etiologia , Celulite Orbitária/complicações , Dacriocistorinostomia/efeitos adversos , Lactente Extremamente Prematuro , Abscesso/complicações , Abscesso/diagnóstico , Dacriocistite/complicações , Dacriocistite/diagnóstico
14.
Circulation ; 146(9): 687-698, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35946404

RESUMO

BACKGROUND: Measurement of fractional flow reserve (FFR) has an established role in guiding percutaneous coronary intervention. We tested the hypothesis that, at the stage of diagnostic invasive coronary angiography, systematic FFR-guided assessment of coronary artery disease would be superior, in terms of resource use and quality of life, to assessment by angiography alone. METHODS: We performed an open-label, randomized, controlled trial in 17 UK centers, recruiting 1100 patients undergoing invasive coronary angiography for the investigation of stable angina or non-ST-segment-elevation myocardial infarction. Patients were randomized to either angiography alone (angiography) or angiography with systematic pressure wire assessment of all epicardial vessels >2.25 mm in diameter (angiography+FFR). The coprimary outcomes assessed at 1 year were National Health Service hospital costs and quality of life. Prespecified secondary outcomes included clinical events. RESULTS: In the angiography+FFR arm, the median number of vessels examined was 4 (interquartile range, 3-5). The median hospital costs were similar: angiography, £4136 (interquartile range, £2613-£7015); and angiography+FFR, £4510 (£2721-£7415; P=0.137). There was no difference in median quality of life using the visual analog scale of the EuroQol EQ-5D-5L: angiography, 75 (interquartile range, 60-87); and angiography+FFR, 75 (interquartile range, 60-90; P=0.88). The number of clinical events was as follows: deaths, 5 versus 8; strokes, 3 versus 4; myocardial infarctions, 23 versus 22; and unplanned revascularizations, 26 versus 33, with a composite hierarchical event rate of 8.7% (48 of 552) for angiography versus 9.5% (52 of 548) for angiography+FFR (P=0.64). CONCLUSIONS: A strategy of systematic FFR assessment compared with angiography alone did not result in a significant reduction in cost or improvement in quality of life. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01070771.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Estenose Coronária/diagnóstico , Humanos , Qualidade de Vida , Medicina Estatal , Resultado do Tratamento
15.
Anal Chem ; 95(4): 2253-2259, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36638820

RESUMO

Double spike (DS) method has been extensively used in determining stable isotope ratios of many elements. However, challenges remain in obtaining high-precision isotope data for ultra-trace elements owing to the limitations of instrumental signal-to-noise ratios and the systematics of precision of DS-based measurements. Here, the DS-standard addition (SA) (DSSA) technique is proposed to improve measurements of isotope compositions of ultra-trace elements in natural samples. According to the U-shaped relationship between DS measurement uncertainty and the spike/sample ratio, theoretical equations and an error propagation model (EPM) were constructed comprehensively. In our method, a spiked secondary standard solution with a high, precisely known spike/sample ratio is mixed with samples such that the mixtures have spike/sample ratios within the optimal range. The abundances of the samples relative to the added standards (sample fraction; fspl) and the samples' isotope ratios can then be obtained exactly using a standard DS data reduction routine and the isotope binary mixing model. The accuracy and precision of the DSSA approach were verified by measurements of cadmium and molybdenum isotopes at as low as 5 ng levels. Compared with traditional DS measurements, the sample size for isotope analysis is reduced to 1/6-1/5 of the original with no loss of measurement precision. The optimal mixing range fspl = 0.15-0.5 is recommended. The DSSA method can be extended to isotope measurement of more than 33 elements where the DS method is applicable, especially for the ultra-trace elements such as platinum group and rare earth element isotopes.

16.
Small ; 19(13): e2202685, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35971193

RESUMO

This article provides a review of the recent development of biomimicking behaviors in active colloids. While the behavior of biological microswimmers is undoubtedly influenced by physics, it is frequently guided and manipulated by active sensing processes. Understanding the respective influences of the surrounding environment can help to engineering the desired response also in artificial swimmers. More often than not, the achievement of biomimicking behavior requires the understanding of both biological and artificial microswimmers swimming mechanisms and the parameters inducing mechanosensory responses. The comparison of both classes of microswimmers provides with analogies in their dependence on fuels, interaction with boundaries and stimuli induced motion, or taxis.


Assuntos
Coloides , Natação , Movimento (Física)
17.
Am Heart J ; 265: 170-179, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37611857

RESUMO

INTRODUCTION: Diffuse disease has been identified as one of the main reasons leading to low post-PCI fractional flow reserve (FFR) and residual angina after PCI. Coronary pressure pullbacks allow for the evaluation of hemodynamic coronary artery disease (CAD) patterns. The pullback pressure gradient (PPG) is a novel metric that quantifies the distribution and magnitude of pressure losses along the coronary artery in a focal-to-diffuse continuum. AIM: The primary objective is to determine the predictive capacity of the PPG for post-PCI FFR. METHODS: This prospective, large-scale, controlled, investigator-initiated, multicenter study is enrolling patients with at least 1 lesion in a major epicardial vessel with a distal FFR ≤ 0.80 intended to be treated by PCI. The study will include 982 subjects. A standardized physiological assessment will be performed pre-PCI, including the online calculation of PPG from FFR pullbacks performed manually. PPG quantifies the CAD pattern by combining several parameters from the FFR pullback curve. Post-PCI physiology will be recorded using a standardized protocol with FFR pullbacks. We hypothesize that PPG will predict optimal PCI results (post-PCI FFR ≥ 0.88) with an area under the ROC curve (AUC) ≥ 0.80. Secondary objectives include patient-reported and clinical outcomes in patients with focal vs. diffuse CAD defined by the PPG. Clinical follow-up will be collected for up to 36 months, and an independent clinical event committee will adjudicate events. RESULTS: Recruitment is ongoing and is expected to be completed in the second half of 2023. CONCLUSION: This international, large-scale, prospective study with pre-specified powered hypotheses will determine the ability of the preprocedural PPG index to predict optimal revascularization assessed by post-PCI FFR. In addition, it will evaluate the impact of PPG on treatment decisions and the predictive performance of PPG for angina relief and clinical outcomes.

18.
Exp Eye Res ; 226: 109341, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36476399

RESUMO

To identify changes in response to experimental intraocular pressure (IOP) elevation associated with the laminin α1 nmf223 mutation in mice. Laminin mutant (LM) mice (Lama1nmf223) and C57BL/6J (B6) mice in two age groups each (4-5 months and >1 year) underwent intracameral microbead injections to produce unilaterally elevated IOP. We assessed axonal transport block of immunofluorescently labeled amyloid precursor protein (APP) after 3 days and retinal ganglion cell (RGC) axon loss after 6 weeks. Light, electron and fluorescent microscopy was used to study baseline anatomic differences and effects of 3-day IOP elevation in younger LM mice. In younger mice of both LM and B6 strains, elevated IOP led to increased APP block in the retina, prelaminar optic nerve head (preONH), unmyelinated optic nerve (UON), and myelinated optic nerve (MON). APP blockade not significantly different between younger B6 and LM mouse strains. Older LM mice had greater APP accumulation in both control and glaucoma eyes compared to older B6, however, accumulation was not significantly greater in LM glaucoma eyes compared to LM controls. Axon loss at 6 weeks was 12.2% in younger LM and 18.7% in younger B6 mice (difference between strains, p = 0.22, Mann Whitney test). Untreated LM optic nerve area was lower compared to B6 (nerve area, p < 0.0001, t-test). Aberrant axon bundles, as well as defects, thickening and reduplication of pia mater, were seen in the optic nerves of younger LM mice. Axonal transport blockade significantly differed between old B6 and old LM mice in control and glaucoma eyes, and younger LM mice had abnormal axon paths and lower optic nerve area.


Assuntos
Glaucoma , Nervo Óptico , Animais , Camundongos , Axônios/patologia , Modelos Animais de Doenças , Glaucoma/genética , Pressão Intraocular , Camundongos Endogâmicos C57BL , Disco Óptico/patologia , Nervo Óptico/patologia , Laminina/genética
19.
Catheter Cardiovasc Interv ; 102(1): 80-90, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37191312

RESUMO

BACKGROUND: We aimed to develop a machine learning algorithm to predict the presence of a culprit lesion in patients with out-of-hospital cardiac arrest (OHCA). METHODS: We used the King's Out-of-Hospital Cardiac Arrest Registry, a retrospective cohort of 398 patients admitted to King's College Hospital between May 2012 and December 2017. The primary outcome was the presence of a culprit coronary artery lesion, for which a gradient boosting model was optimized to predict. The algorithm was then validated in two independent European cohorts comprising 568 patients. RESULTS: A culprit lesion was observed in 209/309 (67.4%) patients receiving early coronary angiography in the development, and 199/293 (67.9%) in the Ljubljana and 102/132 (61.1%) in the Bristol validation cohorts, respectively. The algorithm, which is presented as a web application, incorporates nine variables including age, a localizing feature on electrocardiogram (ECG) (≥2 mm of ST change in contiguous leads), regional wall motion abnormality, history of vascular disease and initial shockable rhythm. This model had an area under the curve (AUC) of 0.89 in the development and 0.83/0.81 in the validation cohorts with good calibration and outperforms the current gold standard-ECG alone (AUC: 0.69/0.67/0/67). CONCLUSIONS: A novel simple machine learning-derived algorithm can be applied to patients with OHCA, to predict a culprit coronary artery disease lesion with high accuracy.


Assuntos
Reanimação Cardiopulmonar , Doença da Artéria Coronariana , Parada Cardíaca Extra-Hospitalar , Humanos , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos , Resultado do Tratamento , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Angiografia Coronária , Algoritmos
20.
Conserv Biol ; 37(4): e14070, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890651

RESUMO

Social media is an arena of debate for contentious political and social topics. One conservation topic debated online is the acceptability of trophy hunting, a debate that has implications for national and international policy. We used a mixed-methods approach (grounded theory and quantitative clustering) to identify themes in the trophy hunting debate on Twitter. We examined commonly co-occurring categories that describe people's stances on trophy hunting. We identified 12 categories and 4 preliminary archetypes opposing trophy hunting-activism, scientific, condemning, and objecting-whose opposition derived from different moral reasoning. Few tweets (22) in our sample of 500 supported trophy hunting, whereas 350 opposed it. The debate was hostile; 7% of tweets in our sample were categorized as abusive. Online debates can be unproductive, and our findings may be important for stakeholders wishing to effectively engage in the trophy hunting debate on Twitter. More generally, we contend that because social media is increasingly influential, it is important to formally contextualize public responses to contentious conservation topics in order to aid communication of conservation evidence and to integrate diverse public perspectives in conservation practice.


Caracterización del debate sobre la cacería de trofeos en Twitter Resumen Las redes sociales son arenas de debate para temas políticos y sociales polémicos. Un tema de conservación que se debate en línea es la aceptación de la cacería de trofeos, cuya discusión tiene implicaciones políticas nacionales e internacionales. Usamos una estrategia de métodos mixtos (teoría fundamentada y datos cuantitativos agrupados) para identificar los temas en el debate sobre la cacería de trofeos en Twitter. Analizamos las categorías concurrentes más comunes que describían la postura de las personas con respecto al tema. Identificamos doce categorías y cuatro arquetipos preliminares en contra de la cacería de trofeos (activista, científico, condenatorio y opositor), cuya oposición derivó de diferentes razonamientos morales. Pocos tuits (22) en nuestra muestra de 500 apoyaban la cacería de trofeos, mientras que 350 se oponían a ella. El debate era hostil, pues 7% de los tuits en nuestra muestra estuvieron categorizados como abusivos. Los debates en línea pueden ser improductivos y nuestros descubrimientos pueden ser importantes para los actores que desean participar de forma efectiva en el debate sobre la cacería de trofeos en Twitter. De manera más generalizada, sostenemos que, debido a la creciente influencia de las redes sociales, es importante que las respuestas públicas a los temas polémicos de conservación estén contextualizadas de manera formal para así auxiliar a la comunicación de la evidencia de conservación y para integrar las diferentes perspectivas públicas en la práctica de la conservación.


Assuntos
Conservação dos Recursos Naturais , Mídias Sociais , Humanos , Comunicação , Conservação dos Recursos Naturais/métodos , Caça , Animais
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