RESUMO
Glycosylation is a critical post-translational protein modification that affects folding, half-life and functionality. Glycosylation is a non-templated and heterogeneous process because of the promiscuity of the enzymes involved. We describe a platform for sequential glycosylation reactions for tailored sugar structures (SUGAR-TARGET) that allows bespoke, controlled N-linked glycosylation in vitro enabled by immobilized enzymes produced with a one-step immobilization/purification method. We reconstruct a reaction cascade mimicking a glycosylation pathway where promiscuity naturally exists to humanize a range of proteins derived from different cellular systems, yielding near-homogeneous glycoforms. Immobilized ß-1,4-galactosyltransferase is used to enhance the galactosylation profile of three IgGs, yielding 80.2-96.3% terminal galactosylation. Enzyme recycling is demonstrated for a reaction time greater than 80 h. The platform is easy to implement, modular and reusable and can therefore produce homogeneous glycan structures derived from various hosts for functional and clinical evaluation.
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Enzimas Imobilizadas , Galactosiltransferases , Glicosilação , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Humanos , Galactosiltransferases/metabolismo , Galactosiltransferases/química , Polissacarídeos/metabolismo , Polissacarídeos/química , Processamento de Proteína Pós-TraducionalRESUMO
Polyglycine hydrolases are fungal effectors composed of an N-domain with unique sequence and structure and a C-domain that resembles ß-lactamases, with serine protease activity. These secreted fungal proteins cleave Gly-Gly bonds within a polyglycine sequence in corn ChitA chitinase. The polyglycine hydrolase N-domain (PND) function is unknown. In this manuscript we provide evidence that the PND does not directly participate in ChitA cleavage. In vitro analysis of site-directed mutants in conserved residues of the PND of polyglycine hydrolase Es-cmp did not specifically impair protease activity. Furthermore, in silico structural models of three ChitA-bound polyglycine hydrolases created by High Ambiguity Driven protein-protein DOCKing (HADDOCK) did not predict significant interactions between the PND and ChitA. Together these results suggest that the PND has another function. To determine what types of PND-containing proteins exist in nature we performed a computational analysis of Foldseek-identified PND-containing proteins. The analysis showed that proteins with PNDs are present throughout biology as either single domain proteins or fused to accessory domains that are diverse but are usually proteases or kinases.
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Peptídeo Hidrolases , Peptídeos , Peptídeos/química , Peptídeo Hidrolases/metabolismo , Endopeptidases/metabolismo , ProteóliseRESUMO
Chromosomal translocations are a hallmark of leukemia/lymphoma and also appear in solid tumors, but the underlying mechanism remains elusive. By establishing a cellular model that mimics the relative frequency of authentic translocation events without proliferation selection, we report mechanisms of nuclear receptor-dependent tumor translocations. Intronic binding of liganded androgen receptor (AR) first juxtaposes translocation loci by triggering intra- and interchromosomal interactions. AR then promotes site-specific DNA double-stranded breaks (DSBs) at translocation loci by recruiting two types of enzymatic activities induced by genotoxic stress and liganded AR, including activation-induced cytidine deaminase and the LINE-1 repeat-encoded ORF2 endonuclease. These enzymes synergistically generate site-selective DSBs at juxtaposed translocation loci that are ligated by nonhomologous end joining pathway for specific translocations. Our data suggest that the confluence of two parallel pathways initiated by liganded nuclear receptor and genotoxic stress underlies nonrandom tumor translocations, which may function in many types of tumors and pathological processes.
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Neoplasias da Próstata/genética , Receptores Androgênicos/metabolismo , Transcrição Gênica , Translocação Genética , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Íntrons , Elementos Nucleotídeos Longos e Dispersos , Masculino , Fases de Leitura Aberta , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulador Transcricional ERGRESUMO
BACKGROUND: Previous meta-analyses combining randomized and observational evidence in cardiac surgery have shown positive impact of enhanced recovery protocols after surgery (ERAS) on postoperative outcomes. However, definitive data based on randomized studies are missing, and the entirety of the ERAS measures and pathway, as recently systematized in guidelines and consensus statements, have not been captured in the published studies. The available literature actually focuses on "ERAS-like" protocols or only limited number of ERAS measures. This study aims at analyzing all randomized studies applying ERAS-like protocols in cardiac surgery for perioperative outcomes. METHODS: A meta-analysis of randomized controlled trials (RCTs) comparing ERAS-like with standard protocols of perioperative care was performed (PROSPERO registration CRD42021283765). PRISMA guidelines were used for abstracting and assessing data. RESULTS: Thirteen single center RCTs (N = 1704, 850 in ERAS-like protocol and 854 in the standard care group) were selected. The most common procedures were surgical revascularization (66.3%) and valvular surgery (24.9%). No difference was found in the incidence of inhospital mortality between the ERAS and standard treatment group (risk ratio [RR] 0.61 [0.31; 1.20], p = 0.15). ERAS was associated with reduced intensive care unit (standardized mean difference [SMD] -0.57, p < 0.01) and hospital stay (SMD -0.23, p < 0.01) and reduced rates of overall complications when compared to the standard protocol (RR 0.60, p < 0.01) driven by the reduction in stroke (RR 0.29 [0.13; 0.62], p < 0.01). A significant heterogeneity in terms of the elements of the ERAS protocol included in the studies was observed. CONCLUSIONS: ERAS-like protocols have no impact on short-term survival after cardiac surgery but allows for a faster hospital discharge while potentially reducing surgical complications. However, this study highlights a significant nonadherence and heterogeneity to the entirety of ERAS protocols warranting further RCTs in this field including a greater number of elements of the framework.
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Procedimentos Cirúrgicos Cardíacos , Recuperação Pós-Cirúrgica Melhorada , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Procedimentos Cirúrgicos Cardíacos/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Tempo de Internação/estatística & dados numéricos , Assistência Perioperatória/métodos , Assistência Perioperatória/normasRESUMO
INTRODUCTION: The use of Left Atrial Appendage (LAA) occluder devices has been on the rise in patients with atrial fibrillation. Studies regarding the long-term risks of occluder devices remain sparse. MATERIALS & METHODS: In this brief report, we discuss the unusual case of an 85-year-old female with long-term complication from Left Atrial Appendage (LAA) closure: Device-Related Thrombus (DRT) about two years after insertion. RESULTS: Compared to the expected stroke rate without anticoagulation, patients with DRT on their LAAO device still had a 28 % relative reduction in ischemic stroke. This suggests that these strokes may have emanated from alternate etiologies other than the DRT. CONCLUSIONS: Patients with active or known history of cancer appears to have a higher risk of DRT. More data is needed on this topic to augment awareness and understanding of LAAO complications and DRT management strategies.
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Apêndice Atrial , Fibrilação Atrial , Acidente Vascular Cerebral , Trombose , Feminino , Humanos , Idoso de 80 Anos ou mais , Oclusão do Apêndice Atrial Esquerdo , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/terapia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Fibrilação Atrial/complicações , Apêndice Atrial/diagnóstico por imagem , Resultado do TratamentoRESUMO
The high incidence of atrial fibrillation (AFib) following cardiac surgery (postoperative atrial fibrillation, POAF) relies on specific surgical features. However, in the setting of POAF, the role of the microbiome in the modulation of cardiac fibrosis is still not clear. This study aimed to analyze the effect of the microbiome and its main metabolic product (trimethylamine-N-oxide, TMAO) in the fibrosis of myocardial tissue, to investigate its role in POAF. Patients undergoing elective cardiac surgery with cardiopulmonary bypass, central atrio-caval cannulation and no history of AFib, were included. A fragment of the right atrium was analyzed for qualitative and mRNA-quantitative evaluation. A preoperative blood sample was analyzed with enzyme-linked immunosorbent assay (ELISA). A total of 100 patients have been included, with POAF occurring in 38%. Histologically, a higher degree of fibrosis, angiogenesis and inflammation has been observed in POAF. Quantitative evaluation showed increased mRNA expression of collagen-1, collagen-3, fibronectin, and transforming growth factor beta (TGFb) in the POAF group. ELISA analysis showed higher levels of TMAO, lipopolysaccharide and TGFb in POAF, with similar levels of sP-selectin and zonulin. TMAO ≥ 61.8 ng/mL (odds ratio, OR 2.88 [1.35-6.16], p = 0.006), preoperative hemoglobin < 13.1 g/dL (OR 2.37 [1.07-5.24], p = 0.033) and impaired right ventricular function (OR 2.38 [1.17-4.83], p = 0.017) were independent predictors of POAF. Also, TMAO was significantly associated with POAF by means of increased fibrosis. Gut microbiome product TMAO is crucial for myocardial fibrosis, which is a key factor for POAF. Patients in preoperative sinus rhythm who will develop POAF have increased genetic expression of pro-fibrotic genes and enhanced fibrosis in histological staining. Elevated TMAO level (≥61.8 ng/mL) is an independent risk factor for POAF.
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Fibrilação Atrial , Fibrose , Microbioma Gastrointestinal , Miocárdio , Humanos , Fibrilação Atrial/etiologia , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Miocárdio/metabolismo , Miocárdio/patologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/microbiologia , Metilaminas/sangue , Metilaminas/metabolismoRESUMO
BACKGROUND: The Florida Stroke Act, signed into law in 2004, set criteria for Comprehensive Stroke Centers (CSC). For a set time period, Florida hospitals were permitted to either receive national certification (NC) or could self-attest (SA) as fulfilling CSC criteria. The aim of this project was to evaluate the quality of ischemic stroke care in NC versus SA stroke centers in Florida, using well-known, guideline-driven ischemic stroke outcome metrics. METHODS: A total of 37 CSCs (74% of Florida CSCs) in the Florida Stroke Registry from January 2013 through December 2018 were analyzed, including 19 SA CSCs and 18 NC (13 CSCs and 5 Thrombectomy-Capable Stroke Center). Hospital- and patient-level characteristics and stroke metrics were evaluated, adjusting for demographics, medical comorbidities, and stroke severity. RESULTS: A total of 78 424 acute ischemic stroke cases, 36 089 from SA CSCs and 42 335 from NC CSC/Thrombectomy-Capable Stroke Centers were analyzed. NC centers had older patients (73 [61-83] versus 71 [60-81]; P<0.001) with more severe strokes (median National Institutes of Health Stroke Scale score of 5 versus 4; P<0.001). NC had higher intravenous tissue-type plasminogen activator utilization (15% versus 13%; P<0.001), endovascular treatment (10% versus 7%; P<0.001) and faster median door-to-computed tomography (23 minutes [11-73] versus 31 [12-78]; P<0.001), door-to-needle (37 minutes [26-50] versus 45 [34-58]; P<0.001) and door-to-puncture times (77 minutes [50-113] versus 93 [62-140]; P<0.001). In adjusted analysis, patients arriving to NC hospitals by 3 hours were more likely to get intravenous tissue-type plasminogen activator in the 3- to 4.5-hour window (adjusted odds ratio, 1.87 [95% CI, 1.30-2.68]; P=0.001) and more likely to be treated with intravenous tissue-type plasminogen activator within 45 minutes (adjusted odds ratio, 1.61 [95% CI, 1.04-2.50]; P=0.04) compared with SA CSCs. CONCLUSIONS: Among Florida-Stroke Registry CSCs, acute ischemic stroke performance and treatment measures at NC centers are superior to SA CSCs. These findings have implications for stroke systems of care in Florida and support legislation updates requiring NC and removal of SA claims.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Ativador de Plasminogênio Tecidual/uso terapêutico , Florida/epidemiologia , Isquemia Encefálica/terapia , Isquemia Encefálica/tratamento farmacológico , AVC Isquêmico/tratamento farmacológico , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/tratamento farmacológico , Sistema de Registros , Certificação , Resultado do Tratamento , Fibrinolíticos/uso terapêutico , Terapia TrombolíticaRESUMO
BACKGROUND: The impact of time to treatment on outcomes of endovascular thrombectomy (EVT) especially in patients presenting after 6 hours from symptom onset is not well characterized. We studied the differences in characteristics and treatment timelines of EVT-treated patients participating in the Florida Stroke Registry and aimed to characterize the extent to which time impacts EVT outcomes in the early and late time windows. METHODS: Prospectively collected data from Get With the Guidelines-Stroke hospitals participating in the Florida Stroke Registry from January 2010 to April 2020 were reviewed. Participants were EVT patients with onset-to-puncture time (OTP) of ≤24 hours and categorized into early window treated (OTP ≤6 hours) and late window treated (OTP >6 and ≤24 hours). Association between OTP and favorable discharge outcomes (independent ambulation, discharge home and to acute rehabilitation facility) as well as symptomatic intracerebral hemorrhage and in-hospital mortality were examined using multilevel-multivariable analysis with generalized estimating equations. RESULTS: Among 8002 EVT patients (50.9% women; median age [±SD], 71.5 [±14.5] years; 61.7% White, 17.5% Black, and 21% Hispanic), 34.2% were treated in the late time window. Among all EVT patients, 32.4% were discharged home, 23.5% to rehabilitation facility, 33.7% ambulated independently at discharge, 5.1% had symptomatic intracerebral hemorrhage, and 9.2% died. As compared with the early window, treatment in the late window was associated with lower odds of independent ambulation (odds ratio [OR], 0.78 [0.67-0.90]) and discharge home (OR, 0.71 [0.63-0.80]). For every 60-minute increase in OTP, the odds of independent ambulation reduced by 8% (OR, 0.92 [0.87-0.97]; P<0.001) and 1% (OR, 0.99 [0.97-1.02]; P=0.5) and the odds of discharged home reduced by 10% (OR, 0.90 [0.87-0.93]; P<0.001) and 2% (OR, 0.98 [0.97-1.00]; P=0.11) in the early and late windows, respectively. CONCLUSIONS: In routine practice, just over one-third of EVT-treated patients independently ambulate at discharge and only half are discharged to home/rehabilitation facility. Increased time from symptom onset to treatment is significantly associated with lower chance of independent ambulation and ability to be discharged home after EVT in the early time window.
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Punções , Tempo para o Tratamento , Humanos , Feminino , Masculino , Hemorragia Cerebral , Florida , Mortalidade HospitalarRESUMO
BACKGROUND: Short-term dual antiplatelet therapy (DAPT) reduces early stroke recurrence after mild noncardioembolic ischemic stroke (NCIS). We aim to evaluate temporal trends and determinants of DAPT prescription after mild NCIS in the Florida Stroke Registry, a statewide registry across Get With The Guidelines-Stroke participating hospitals. METHODS: In this cross-sectional analysis of a cohort study, we included patients with mild NCIS (National Institutes of Health Stroke Scale score ≤3) who were potentially eligible for DAPT across 168 Florida Stroke Registry participating hospitals between January 2010 and September 2022. Using antiplatelet prescription as the dependent variable (DAPT versus single antiplatelet therapy), we fit logistic regression models adjusted for patient-related factors, hospital-related factors, clinical presentation, vascular risk factors, and ischemic stroke subtype, to obtain adjusted odds ratios (aORs) with 95% CIs. RESULTS: From 283â 264 Florida Stroke Registry ischemic stroke patients during the study period, 109â 655 NCIS were considered eligible. Among these, 37â 058 patients with National Institutes of Health Stroke Scale score >3 were excluded, resulting in a sample of 72â 597 mild NCIS (mean age 68±14 years; female 47.3%). Overall, 24â 693 (34.0%) patients with mild NCIS were discharged on DAPT and 47â 904 (66.0%) on single antiplatelet therapy. DAPT prescription increased from 25.7% in 2010 to 52.8% in 2022 (ß/year 2.5% [95% CI, 1.5%-3.4%]). Factors associated with DAPT prescription were premorbid antiplatelet therapy (aOR, 4.66 [95% CI, 2.20-9.88]), large-artery atherosclerosis (aOR, 1.68 [95% CI, 1.43-1.97]), diabetes (aOR, 1.29 [95% CI, 1.13-1.47]), and hyperlipidemia (aOR, 1.24 [95% CI, 1.10-1.39]), whereas female sex (aOR, 0.83 [95% CI, 0.75-0.93]), being non-Hispanic Black patients (compared with non-Hispanic White patients; aOR, 0.78 [95% CI, 0.68-0.90]), admission to a Thrombectomy-capable Stroke Center (compared with Comprehensive Stroke Center; aOR, 0.78 [95% CI, 0.66-0.92]), time-to-presentation 1 to 7 days from last seen well (compared with <24 h; aOR, 0.86 [95% CI, 0.76-0.96]), and small-vessel disease stroke (aOR, 0.81 [95% CI, 0.72-0.94]) were associated with not receiving DAPT at discharge. CONCLUSIONS: Despite a temporal trend increase in DAPT prescription after mild NCIS, we found substantial underutilization of evidence-based DAPT associated with significant disparities in stroke care.
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AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Inibidores da Agregação Plaquetária/uso terapêutico , Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Estudos de Coortes , Estudos Transversais , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/induzido quimicamente , AVC Isquêmico/tratamento farmacológico , Quimioterapia Combinada , Resultado do TratamentoRESUMO
OBJECTIVE: Stroke is a global public health burden, and therefore it is critical to identify modifiable risk factors to reduce stroke incidence and improve outcomes. Depression is such a risk factor; however, the association between preexisting depression and stroke outcomes, such as independent ambulation, is not well studied, especially among racial-ethnic minority groups. To address this gap in the literature, effects of preexisting depression on ambulatory status at hospital discharge after stroke were evaluated among individuals participating in the racially and ethnically diverse Florida-Puerto Rico Collaboration to Reduce Stroke Disparities project. METHODS: Data were analyzed from a total of 42,031 ischemic stroke patients, who were independently ambulatory prior to their stroke, after discharge from 84 hospitals between 2014 and 2017. Preexisting depression was confirmed by medical history or antidepressant medication use. Multilevel multivariate logistic regression analyses were used to assess the association of preexisting depression with independent ambulation at hospital discharge. Effects of sex and race-ethnicity on this association were examined. RESULTS: Of 42,031 participants (mean±SD age=70.4±14.2 years; 48% were female; race-ethnicity: 16% Black, 12% Hispanic living in Florida, and 7% Hispanic living in Puerto Rico), 6,379 (15%) had preexisting depression. Compared with participants without depression, those with preexisting depression were older, were more likely to be female and non-Hispanic White, and had a greater burden of vascular risk factors or comorbid conditions. Independent ambulation at hospital discharge was less frequent among women, Black participants, and individuals with vascular risk factors or comorbid conditions. In multivariate models, preexisting depression decreased the likelihood of independent ambulation at discharge (odds ratio=0.88, 95% CI=0.81, 0.97). No interactions were found between preexisting depression and race-ethnicity or sex. CONCLUSIONS: Preexisting depression was independently associated with dependent ambulation at hospital discharge after stroke, regardless of sex and race-ethnicity. Treating depression may contribute to primary stroke prevention and could improve ambulatory status at discharge.
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Etnicidade , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Porto Rico/epidemiologia , Florida/epidemiologia , Depressão/epidemiologia , Sistema de Registros , Grupos Minoritários , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologiaRESUMO
While the transcriptional machinery has been extensively dissected at the molecular level, little is known about regulation of chromosomal organization in the three-dimensional space of the nucleus to achieve integrated transcriptional responses to diverse signaling events. Here, we report that ligand induces rapid interchromosomal interactions among subsets of estrogen receptor alpha-bound transcription units, with a dramatic reorganization of nuclear territories requiring nuclear actin/myosin-I transport machinery, dynein light chain 1 (DLC1), and a specific subset of transcriptional coactivators and chromatin remodeling complexes. We establish a requirement for the histone lysine demethylase, LSD1, in directing specific interchromosomal interaction loci to distinct interchromatin granules, long thought to be "storage" sites for splicing machinery, and demonstrate that these three-dimensional motor-dependent interactions are required to achieve enhanced transcription of specific estrogen-receptor target genes. These findings reveal roles for the modulation of nuclear architecture in orchestrating regulated gene-expression programs in the mammalian nucleus.
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Cromatina/metabolismo , Receptor alfa de Estrogênio/metabolismo , Redes Reguladoras de Genes , Proteínas Motores Moleculares/metabolismo , Oxirredutases N-Desmetilantes/metabolismo , Actinas/metabolismo , Linhagem Celular Tumoral , Núcleo Celular , Células Cultivadas , Histona Desmetilases , Humanos , Corpos de Inclusão Intranuclear/metabolismo , Transcrição GênicaRESUMO
Digital Livestock Technologies (DLTs) can assist farmer decision-making and promise benefits to animal health and welfare. However, the extent to which they can help improve animal welfare is unclear. This study explores how DLTs may impact farm management and animal welfare by promoting learning, using the concept of boundary objects. Boundary objects may be interpreted differently by different social worlds but are robust enough to share a common identity across them. They facilitate communication around a common issue, allowing stakeholders to collaborate and co-learn. The type of learning generated may impact management and welfare differently. For example, it may help improve existing strategies (single-loop learning), or initiate reflection on how these strategies were framed initially (double-loop learning). This study focuses on two case studies, during which two DLTs were developed and tested on farms. In-depth, semi-structured interviews were conducted with stakeholders involved in the case studies (n = 31), and the results of a separate survey were used to complement our findings. Findings support the important potential of DLTs to help enhance animal welfare, although the impacts vary between technologies. In both case studies, DLTs facilitated discussions between stakeholders, and whilst both promoted improved management strategies, one also promoted deeper reflection on the importance of animal emotional well-being and on providing opportunities for positive animal welfare. If DLTs are to make significant improvements to animal welfare, greater priority should be given to DLTs that promote a greater understanding of the dimensions of animal welfare and a reframing of values and beliefs with respect to the importance of animals' well-being.
RESUMO
First, I agree with Cheng that the argument from illusions to indirect realism is controversial, especially as to what is meant by "realism," "veridical," and "sense data" and the background assumptions underlying them. I provide a finer specification of some of the sub-movements that were the specific concerns of my previous article, particularly phenomenology as it currently sees itself in perception research, and the relevance of illusions. Perception has turned out to be far more complex than traditional philosophy realized, as has been revealed by recent research in neuroscience and psychophysics. Lastly, I answer Cheng's question about the "causal exclusion argument" by suggesting it is obviated by the temporal substructure of metaphysical states, and I provide a detailed supporting case in Supplementary Material.
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Ilusões , Humanos , Metafísica , Filosofia , PsicofísicaRESUMO
Illusions are commonly defined as departures of our percepts from the veridical representation of objective, common-sense reality. However, it has been claimed recently that this definition lacks validity, for example, on the grounds that external reality cannot possibly be represented truly by our sensory systems, and indeed may even be a fiction. Here, I first demonstrate how novelist George Orwell warned that such denials of objective reality are dangerous mistakes, in that they can lead to the suppression and even the atrophy of independent thought and critical evaluation. Second, anti-realists assume their opponents hold a fully reductionist metaphysics, in which fundamental physics describes the only ground truth, thereby placing it beyond direct human sensory observation. In contrast, I point to a more recent and commonly used alternative, non-reductive metaphysics. This ascribes real existence to many levels of dynamic systems of information, emerging progressively from the subatomic to the biological, psychological, social, and ecological. Within such a worldview the notion of objective reality is valid, it comes in part within the range of our senses, and thus a definition of illusions as kinds of deviations from veridical perception becomes possible again.
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Ilusões , Humanos , FísicaRESUMO
OBJECTIVES: Blood transfusions after coronary artery bypass grafting (CABG) has been associated to adverse outcomes, especially in anemic patients. However, little is known about the influence of the modality of revascularization. Total arterial revascularization (TAR) was shown to reduce postoperative transfusion when compared to saphenous vein-based (SV)-CABG (LIMA plus one/more SV grafts). We, therefore, aimed to investigate the impact of TAR-CABG versus SV-CABG on blood products use and perioperative outcomes in patients with preoperative anemia, normally at higher risk for postoperative transfusions. METHODS: From a cohort of 936 patients with mild preoperative anemia undergoing primary elective on-pump CABG, 166 matched pairs of patients undergoing either TAR- or SV-CABG were obtained. Anemia was defined as hemoglobin level <13 g/dl for men and <12 g/dl for women. The primary endpoint was the evaluation of red packed cells (RPC) use over the entire hospital stay. RESULTS: TAR patients showed significantly reduced RPC usage compared with SV (mean difference 0.45 units). TAR patients had a reduced intubation time (mean difference 7.6 h) and were discharged 1.24 days earlier than SV patients. Pneumonia and acute kidney injury were doubled among SV patients. Adjusted regression showed that TAR technique is a predictor of reduced RPC unit use regardless of age and EuroSCORE II (odds ratio: 0.63, p < .01). CONCLUSION: Patients with preoperative anemia might benefit from TAR regardless of age or calculated operative risk. TAR-CABG was associated to reduced postoperative use of blood products and postoperative length of stay in comparison with SV-CABG in this subset of patients.
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Anemia , Doença da Artéria Coronariana , Anemia/complicações , Transfusão de Sangue , Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/cirurgia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Veia Safena/transplante , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: It is unknown when to start anticoagulation after acute ischemic stroke (AIS) from atrial fibrillation (AF). Early anticoagulation may prevent recurrent infarctions but may provoke hemorrhagic transformation as AF strokes are typically larger and hemorrhagic transformation-prone. Later anticoagulation may prevent hemorrhagic transformation but increases risk of secondary stroke in this time frame. Our aim was to compare early anticoagulation with apixaban in AF patients with stroke or transient ischemic attack (TIA) versus warfarin administration at later intervals. METHODS: AREST (Apixaban for Early Prevention of Recurrent Embolic Stroke and Hemorrhagic Transformation) was an open-label, randomized controlled trial comparing the safety of early use of apixaban at day 0 to 3 for TIA, day 3 to 5 for small-sized AIS (<1.5 cm), and day 7 to 9 for medium-sized AIS (≥1.5 cm, excluding full cortical territory), to warfarin, in a 1:1 ratio at 1 week post-TIA, or 2 weeks post-AIS. RESULTS: Although AREST ended prematurely after a national guideline focused update recommended direct oral anticoagulants over warfarin for AF, it revealed that apixaban had statistically similar yet generally numerically lower rates of recurrent strokes/TIA (14.6% versus 19.2%, P=0.78), death (4.9% versus 8.5%, P=0.68), fatal strokes (2.4% versus 8.5%, P=0.37), symptomatic hemorrhages (0% versus 2.1%), and the primary composite outcome of fatal stroke, recurrent ischemic stroke, or TIA (17.1% versus 25.5%, P=0.44). One symptomatic intracerebral hemorrhage occurred on warfarin, none on apixaban. Five asymptomatic hemorrhagic transformation occurred in each arm. CONCLUSIONS: Early initiation of anticoagulation after TIA, small-, or medium-sized AIS from AF does not appear to compromise patient safety. Potential efficacy of early initiation of anticoagulation remains to be determined from larger pivotal trials. Registration: URL: https://www.clinicaltrials.gov/; Unique identifier: NCT02283294.
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Fibrilação Atrial/complicações , Inibidores do Fator Xa/administração & dosagem , AVC Isquêmico/etiologia , Pirazóis/administração & dosagem , Piridonas/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/etiologia , Feminino , Humanos , AVC Isquêmico/prevenção & controle , Masculino , Pessoa de Meia-Idade , RecidivaRESUMO
BACKGROUND: Increased gastric wall activity on myocardial perfusion imaging (MPI) is associated with proton pump inhibitor (PPI) therapy; however, the mechanism is unknown. We proposed a role for gastric mucosal prostaglandin synthesis and asked whether concurrent use of aspirin would antagonize this effect. METHODS: An observational study was performed of 319 patients undergoing technetium-99m sestamibi (MIBI) rest/stress MPI. We assessed the effects of taking PPIs, aspirin and their interaction on the principle outcome of clinically significant gastric wall activity. RESULTS: The outcome was observed in 13% of patients taking neither a PPI nor aspirin, 22% of those taking aspirin only, 51% taking a PPI only and 33% of those taking both. Adjusted odd ratios (95% confidence intervals) were 6.3 (CI 2.8-14.0; p < .001) for taking a PPI only, 1.8 (CI 0.8-3.9; p = .16) for taking aspirin only, and 3.0 (CI 1.4-6.5; p = .005) for taking the combination of a PPI and aspirin. There was evidence of negative statistical interaction between the two drug effects using additive (p = .006) and multiplicative (p = .016) scales. CONCLUSIONS: PPI use was strongly associated with enhanced gastric wall activity on MPI; however, concurrent aspirin appears to reduce the effect. Enhanced local prostaglandin synthesis may mediate the PPI effect.
Assuntos
Aspirina/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Imagem de Perfusão do Miocárdio , Inibidores da Bomba de Prótons/farmacologia , Estômago/metabolismo , Tecnécio Tc 99m Sestamibi/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Interações Medicamentosas , Feminino , Mucosa Gástrica/metabolismo , Cardiopatias/diagnóstico por imagem , Cardiopatias/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacocinéticaRESUMO
Background and Purpose- The RE-SPECT ESUS trial (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) tested the hypothesis that dabigatran would be superior to aspirin for the prevention of recurrent stroke in patients with embolic stroke of undetermined source. This exploratory subgroup analysis investigates the impact of age, renal function (both predefined), and dabigatran dose (post hoc) on the rates of recurrent stroke and major bleeding. Methods- RE-SPECT ESUS was a multicenter, randomized, double-blind trial of dabigatran 150 or 110 mg (for patients aged ≥75 years and/or with creatinine clearance 30 to <50 mL/minute) twice daily compared with aspirin 100 mg once daily. The primary outcome was recurrent stroke. Results- The trial, which enrolled 5390 patients from December 2014 to January 2018, did not demonstrate superiority of dabigatran versus aspirin for prevention of recurrent stroke in patients with embolic stroke of undetermined source. However, among the population qualifying for the lower dabigatran dose, the rate of recurrent stroke was reduced with dabigatran versus aspirin (7.4% versus 13.0%; hazard ratio, 0.57 [95% CI, 0.39-0.82]; interaction P=0.01). This was driven mainly by the subgroup aged ≥75 years (7.8% versus 12.4%; hazard ratio, 0.63 [95% CI, 0.43-0.94]; interaction P=0.10). Stroke rates tended to be lower with dabigatran versus aspirin with declining renal function. Risks for major bleeding were similar between treatments, irrespective of renal function, but with a trend for lower bleeding rates with dabigatran versus aspirin in older patients. Conclusions- In subgroup analyses of RE-SPECT ESUS, dabigatran reduced the rate of recurrent stroke compared with aspirin in patients qualifying for the lower dose of dabigatran. These results are hypothesis-generating. Aspirin remains the standard antithrombotic treatment for patients with embolic stroke of undetermined source. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239120.
Assuntos
Aspirina , Dabigatrana , Fibrinolíticos , Embolia Intracraniana , Nefropatias , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Aspirina/administração & dosagem , Aspirina/farmacocinética , Dabigatrana/administração & dosagem , Dabigatrana/farmacocinética , Método Duplo-Cego , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/farmacocinética , Humanos , Embolia Intracraniana/sangue , Embolia Intracraniana/tratamento farmacológico , Nefropatias/sangue , Nefropatias/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Recidiva , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
The aim of the study was to identify reporting patterns of ventilation and perfusion single-photon emission computed tomography (V/Q SPECT) scans done in our department over 3 months in 2016. Factors impacting on reporting and patient groups that would most benefit from the addition of low-dose computed tomography (CT) to V/Q SPECT were analysed. Among 178 patients, 173 (97.2%) had a definitive (positive/negative) report and 2.8% had an equivocal report. As the majority of the equivocal reports were seen in patients aged ≥70 years, we believe that addition of low-dose CT with V/Q SPECT to this patient group will reduce the non-diagnostic rate.