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Aim: We investigate combining Prussian Blue nanoparticles (PBNPs), as photothermal therapy (PTT) agents, with agonistic CD137 antibodies (αCD137) on a single nanoparticle platform to deliver non-toxic, anti-tumor efficacy in SM1 murine melanoma.Methods: We electrostatically coated PBNPs with αCD137 (αCD137-PBNPs) and quantified their physicochemical characteristics, photothermal and co-stimulatory capabilities. Next, we tested the efficacy and hepatotoxicity of PTT using αCD137-PBNPs (αCD137-PBNP-PTT) in SM1 tumor-bearing mice.Results: The αCD137-PBNPs retained both the photothermal and agonistic properties of the PBNPs and αCD137, respectively. In vivo, SM1 tumor-bearing mice treated with αCD137-PBNP-PTT exhibited a significantly higher survival rate (50%) without hepatotoxicity, compared with control treatments.Conclusion: These data suggest the potential utility of co-localizing PBNP-PTT with αCD137-based agonism as a novel combination nanomedicine.
Photothermal therapy is a strategy to kill cancer cells that uses nanoparticles and lasers to generate heat. Here, we combine photothermal therapy with an immunotherapy that activates the body's T cells, a type of white blood cell, on a single platform, to treat melanoma, a type of skin cancer in a mouse. We find that this novel nanoparticle-based platform significantly improves the survival of mice bearing melanoma, without increasing liver toxicity.
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Every chemical group that is added to any one of the canonical ribonucleotides in a transcript would create a specific RNA modification. Currently, 170+ RNA modifications have been identified. A specific epitranscriptome refers to all the RNA modifications in a given biological system and is considered to play an important role in the regulations of cellular activities. Mass spectrometry-based methods have proven to be the most accurate way to identify RNA modifications and determine the amount of each detectable modification. Relating to the recent development of mapping specific RNA modifications within a transcriptome, the profiling of all RNA modifications can serve as a prescreening tool for mapping and provides support for analyzing the data obtained from mapping. In this chapter, the details for setting up a commonly used mass spectrometry-based method to profile all the RNA modifications in specific epitranscriptomes are described, and the possible options if available are discussed.
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Espectrometria de Massas , Processamento Pós-Transcricional do RNA , RNA , Transcriptoma , RNA/genética , Espectrometria de Massas/métodos , Humanos , Epigênese Genética , Epigenômica/métodos , Perfilação da Expressão Gênica/métodosRESUMO
BACKGROUND: Metformin and sodium-glucose cotransporter-2 (SGLT2) inhibitors have demonstrated cardiovascular benefits but their comparative effects on mortality in type 2 diabetes mellitus (T2DM) patients with cardiovascular disease (CVD) are unknown. Hence, we evaluated and compared lifetime benefits arising from metformin or SGLT2 inhibitors in T2DM patients with CVD. MATERIALS AND METHODS: Studies published in the PubMed, EMBASE and CENTRAL databases before 28 October 2023 were retrieved. Treatment effects of metformin against US FDA-approved SGLT2 inhibitors in T2DM patients with CVD were evaluated and lifetime gains in event-free survival were estimated from our primary endpoints of all-cause and cardiovascular mortality. Risk ratios were derived to assess their impact on secondary outcomes such as major adverse cardiovascular events and hospitalizations for heart failure. RESULTS: Overall, 14 studies were included. Five studies published Kaplan-Meier curves for the primary outcome of all-cause mortality. Individual participant data were reconstructed from these Kaplan-Meier curves, from which we conducted our two-stage meta-analysis. Participants receiving metformin and SGLT2 inhibitors experienced a reduction in the risk for all-cause mortality as compared with those not taking metformin and placebo. However, participants receiving SGLT2 inhibitors had a higher all-cause mortality (hazard ratio 1.308, 95% confidence interval 1.103-1.550) versus metformin. Treatment with metformin was estimated to offer an additional 23.26 months of survival free from all-cause mortality versus 23.04 months with SGLT2 inhibitors. CONCLUSIONS: In patients with T2DM and CVD, metformin and SGLT2 inhibitors were associated with substantially lower all-cause mortality rates and slightly longer life expectancies than in patients without. Metformin presented an advantage over SGLT2 inhibitors in reducing all-cause mortality.
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Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Metformina , Inibidores do Transportador 2 de Sódio-Glicose , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Metformina/uso terapêutico , Hipoglicemiantes/uso terapêuticoRESUMO
We explore the open-ended nature of evolution in Genelife, an evolutionary extension of Conway's Game of Life cellular automaton in which "live" cell states are endowed at birth with a genome that affects their local dynamics and can be inherited. Both genetic sequences and locally connected spatial patterns are analyzed for novelty, keeping track of all new structures, and innovation is quantified using activity statistics. The impacts of both spatial symmetry breaking with nontotalistic rules and superimposed density regulation of the live state proliferation on the open-ended nature of the evolution are explored. Conditions are found where both genetic and spatial patterns exhibit open-ended innovation. This innovation appears to fall short of functional biological innovation, however, and potential reasons for this are discussed.
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Evolução Biológica , Modelos GenéticosRESUMO
Johne's disease (JD) is an infectious enteric disease in ruminants, causing substantial economic loss annually worldwide. This work aimed to estimate JD's genetic parameters and the phenotypic and genetic trends by incorporating recent data. It also explores the feasibility of a national genetic evaluation for JD susceptibility in Holstein cattle in the United States. The data were extracted from a JD data repository, maintained at the Council on Dairy Cattle Breeding, and initially supplied by 2 dairy record processing centers. The data comprised 365,980 Holstein cows from 1,048 herds participating in a voluntary control program for JD. Two protocol kits, IDEXX Paratuberculosis Screening Ab Test (IDX) and Parachek 2 (PCK), were used to analyze milk samples with the ELISA technique. Test results from the first 5 parities were considered. An animal was considered infected if it had at least one positive outcome. The overall average of JD incidence was 4.72% in these US Holstein cattle. Genotypes of 78,964 SNP markers were used for 25,000 animals randomly selected from the phenotyped population. Variance components and genetic parameters were estimated based on 3 models, namely, a pedigree-only threshold model (THR), a single-step threshold model (ssTHR), and a single-step linear model (ssLR). The posterior heritability estimates of JD susceptibility were low to moderate: 0.11 to 0.16 based on the 2 threshold models and 0.05 to 0.09 based on the linear model. The average reliability of EBVs of JD susceptibility using single-step analysis for animals with or without phenotypes varied from 0.18 (THR) to 0.22 (ssLR) for IDX and from 0.14 (THR) to 0.18 (ssTHR and ssLR) for PCK. Despite no prior direct genetic selection against JD, the estimated genetic trends of JD susceptibility were negative and highly significant. The correlations of bulls' PTA with economically important traits such as milk yield, milk protein, milk fat, somatic cell score, and mastitis were low, indicating a nonoverlapping genetic selection process with traits in current genetic evaluations. Our results suggest the feasibility of reducing the JD incidence rate by incorporating it into the national genetic evaluation programs.
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Doenças dos Bovinos , Genótipo , Paratuberculose , Fenótipo , Animais , Bovinos/genética , Paratuberculose/genética , Doenças dos Bovinos/genética , Feminino , Leite , Cruzamento , Estados UnidosRESUMO
We report an uncommon case report of total anomalous pulmonary venous returns into the right atrium at the base of the superior caval vein's ostium without a sinus venosus defect, in situs solitus, without vertical vein or a posterior pulmonary venous confluence.
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Comunicação Interatrial , Veias Pulmonares , Síndrome de Cimitarra , Humanos , Síndrome de Cimitarra/diagnóstico por imagem , Veia Cava Superior/diagnóstico por imagem , Veia Cava Superior/anormalidades , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/anormalidades , Comunicação Interatrial/diagnóstico , Comunicação Interatrial/diagnóstico por imagem , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/anormalidadesRESUMO
The term 'insight' is generically defined in English language as the ability to perceive deeper truths about people and situations. In clinical practice, patient insight is known to have important implications in treatment compliance and clinical outcomes, and can be assessed clinically by looking for the presence of illness awareness, correct attribution of symptoms to underlying condition, and acceptance of treatment. In this article, we suggest that cultivating insight is actually a highly important, yet often overlooked, component of medical training, which may explain why some consistently learn well, communicate effectively, and quickly attain clinical competency, while others struggle throughout their clinical training and may even be difficult to remediate. We herein define 'insight' in the context of medical training as having an astute perception of personal cognitive processes, motivations, emotions, and ability (strengths, weaknesses, and limitations) that should drive self-improvement and effective behavioural regulation. We then describe the utility of cultivating 'insight' in medical training through three lenses of (i) promoting self-regulated, lifelong clinical learning, (ii) improving clinical competencies and person-centred care, and (iii) enhancing physician mental health and well-being. In addition, we review educational pedagogies that are helpful to create a medical eco-system that promotes the cultivation of insight among its trainees and practitioners. Finally, we highlight several tell-tale signs of poor insight and discuss psychological and non-psychological interventions that may help those severely lacking in insight to become more amenable to change and remediation.
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Educação Médica , Aprendizagem , Saúde Mental , Humanos , Competência Clínica , Assistência Centrada no PacienteRESUMO
OBJECTIVE: There is no consensus on the optimal anticoagulant regimen following lower extremity bypass. Historically, warfarin has been utilized for prosthetic or compromised vein bypasses. Direct-acting oral anticoagulants (DOACs) are increasingly replacing warfarin in this context, but their efficacy in bypass preservation has not been well-studied. Recent studies have shown that DOACs may improve outcomes following bypasses; however, it is unclear if this is dependent upon type of bypass conduit. The goal of this study was to evaluate whether a difference exists between vein and prosthetic infra-geniculate bypasses outcomes based on the anticoagulant utilized on discharge, warfarin or DOAC. METHODS: The Vascular Quality Initiative infra-inguinal bypass database was queried for all patients who underwent an infra-geniculate bypass and were anticoagulation-naive at baseline but were discharged on either warfarin or DOACs. A survival analysis was performed for patients up to 1 year to determine whether the choice of discharge anticoagulation was associated with differences between those with vein vs prosthetic conduits in overall survival, primary patency, risk of amputation, or risk of major adverse limb events (MALE). A multivariable Cox proportional hazards analysis was performed to control for differences in baseline demographic factors between the groups. RESULTS: During the study period (2003-2020), 57,887 patients underwent infra-geniculate bypass. Of these, 3230 (5.5%) were anticoagulated on discharge. There was a similar distribution of anticoagulation between vein (n = 1659; 51.4%) and prosthetic conduits (n = 1571; 48.6%). Thirty-two percent were discharged on DOACs, and 68.0% were discharged on warfarin. For prosthetic conduits, being discharged on a DOAC was associated with improved outcomes on univariate and multivariable analyses revealing lower risk of overall mortality (hazard ratio [HR], 0.61; 95% confidence interval [CI], 0.41-0.93; P = .021), loss of primary patency (HR, 0.70; 95% CI, 0.55-0.89; P = .003), risk of amputation (HR, 0.71; 95% CI, 0.54-0.93; P = .013), and risk of MALE (HR, 0.80; 95% CI, 0.64-1.00; P = .048). Patients with a vein bypass had improved univariate outcomes for survival and primary patency; however, with multivariable analysis, there were no significant differences in outcomes between DOAC and warfarin. CONCLUSIONS: Anticoagulation-naive patients who underwent an infra-geniculate prosthetic bypass had higher rates of overall survival, bypass patency, amputation-free survival, and freedom from MALE when discharged on a DOAC compared with warfarin. Those with vein bypasses had similar outcomes regardless of the choice of anticoagulation.
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Implante de Prótese Vascular , Varfarina , Humanos , Varfarina/efeitos adversos , Alta do Paciente , Implante de Prótese Vascular/efeitos adversos , Resultado do Tratamento , Grau de Desobstrução Vascular , Fatores de Risco , Anticoagulantes/efeitos adversos , Prótese Vascular , Estudos RetrospectivosRESUMO
Clopidogrel, an anti-platelet drug, used to prevent thrombosis after percutaneous coronary intervention. Clopidogrel resistance results in recurring ischemic episodes, with African Americans suffering disproportionately. The aim of this study was to identify biomarkers of clopidogrel resistance in African American patients. We conducted a genome-wide association study, including local ancestry adjustment, in 141 African Americans on clopidogrel to identify associations with high on-treatment platelet reactivity (HTPR). We validated genome-wide and suggestive hits in an independent cohort of African American clopidogrel patients (N = 823) from the Million Veteran's Program (MVP) along with in vitro functional follow up. We performed differential gene expression (DGE) analysis in whole blood with functional follow-up in MEG-01 cells. We identified rs7807369, within thrombospondin 7A (THSD7A), as significantly associated with increasing risk of HTPR (p = 4.56 × 10-9). Higher THSD7A expression was associated with HTPR in an independent gene expression cohort of clopidogrel treated patients (p = 0.004) and supported by increased gene expression on THSD7A in primary human endothelial cells carrying the risk haplotype. Two SNPs (rs1149515 and rs191786) were validated in the MVP cohort. DGE analysis identified an association with decreased LAIR1 expression to HTPR. LAIR1 knockdown in a MEG-01 cells resulted in increased expression of SYK and AKT1, suggesting an inhibitory role of LAIR1 in the Glycoprotein VI pathway. Notably, the CYP2C19 variants showed no association with clopidogrel response in the discovery or MVP cohorts. In summary, these finding suggest that other variants outside of CYP2C19 star alleles play an important role in clopidogrel response in African Americans.
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Various methods have been proposed to estimate daily yield from partial yields, primarily to deal with unequal milking intervals. This paper offers an exhaustive review of daily milk yields, the foundation of lactation records. Seminal advancements in the late 20th century concentrated on two main adjustment metrics: additive additive correction factors (ACF) and multiplicative correction factors (MCF). An ACF model provides additive adjustments to two times AM or PM milk yield, which then becomes the estimated daily yields, whereas an MCF is a ratio of daily yield to the yield from a single milking. Recent studies highlight the potential of alternative approaches, such as exponential regression and other nonlinear models. Biologically, milk secretion rates are not linear throughout the entire milking interval, influenced by the internal mammary gland pressure. Consequently, nonlinear models are appealing for estimating daily milk yields as well. MCFs and ACFs are typically determined for discrete milking interval classes. Nonetheless, large discrete intervals can introduce systematic biases. A universal solution for deriving continuous correction factors has been proposed, ensuring reduced bias and enhanced daily milk yield estimation accuracy. When leveraging test-day milk yields for genetic evaluations in dairy cattle, two predominant statistical models are employed: lactation and test-day yield models. A lactation model capitalizes on the high heritability of total lactation yields, aligning closely with dairy producers' needs because the total amount of milk production in a lactation directly determines farm revenue. However, a lactation yield model without harnessing all test-day records may ignore vital data about the shapes of lactation curves needed for informed breeding decisions. In contrast, a test-day model emphasizes individual test-day data, accommodating various intervals and recording plans and allowing the estimation of environmental effects on specific test days. In the United States, the patenting of test-day models in 1993 used to restrict the use of test-day models to regional and unofficial evaluations by the patent holders. Estimated test-day milk yields have been used as if they were accurate depictions of actual milk yields, neglecting possible estimation errors. Its potential consequences on subsequent genetic evaluations have not been sufficiently addressed. Moving forward, there are still numerous questions and challenges in this domain.
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PURPOSE: The purpose of this study is to compare the factors of taper, length, angle and number of vertical axial walls that affect the retentive strength of a cemented crown on a partially customizedhybrid abutment in the esthetic zone. MATERIALS AND METHOD: A total of 35 metal copings were used in this study divided into one group with 30 copings cemented to their corresponding 8° tapered abutment with lengths from 3 to 8 mm with 1 mm increments. The remaining five consisted of a standardized metal coping matching a hexagonal abutment with 3 mm vertical axial walls and the sequential removal of 1, 2, and 3 contiguous vertical axial walls. Dislodgment tests were performed for all copings in both groups. Maximum retentive forces were measured in kgF with a conversion factor of 9.807 N to 1 kgF. RESULTS: At each tapered abutment length, the retentive strength increased proportionally and was significantly different from 31.67 ± SD 4.10 kgF to 67.68 ± SD 11.22 kgF, respectively [F (5,24) =20.46, p < 0.001]. An unmodified hexagonal abutment demonstrated the highest retentive strength of 70.15 ± SD 12.97 kgF. Sequential removal of 1, 2, and 3 contiguous vertical axial walls of the hexagonal abutment was 59.89 ± SD 10.06 kgF, 57.01 ± SD 9.62 kgF, and 55.99 ± SD 9.35 kgF, respectively with no significant difference (p > 0.05) in retentive strength. CONCLUSION: A partially customized abutment with vertical axial walls on one side and a profile reduction on the opposite side can provide comparable retention of cemented copings at 1/3 the length and 1/6 the surface area of an 8 mm high abutment with an 8° taper.
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This study compared 3 correlational (best prediction, linear regression, and feed-forward neural networks) and 2 causal models (recursive structural equation model and recurrent neural networks) for estimating lactation milk yields. The correlational models assumed associations between test-day milk yields (health conditions), while the casual models postulated unidirectional recursive effects between these test-day variables. Wood lactation curves were used to simulate the data and served as a benchmark model. Individual Wood lactation curves provided an excellent parametric interpretation of lactation dynamics, with their prediction accuracies depending on the coverage of the lactation curve dynamics. Best prediction outperformed other models in the absence of mastitis but was suboptimal when mastitis was present and unaccounted for. Recurrent neural networks yielded the highest accuracy when mastitis was present. Although causal models facilitated the inference about the causality underlying lactation, precisely capturing the causal relationships was challenging because the underlying biology was complex. Misspecification of recursive effects in the recursive structural equation model resulted in a loss of accuracy. Hence, modeling causal relationships does not necessarily guarantee improved accuracies. In practice, a parsimonious model is preferred, balancing model complexity and accuracy. In addition to the choice of statistical models, the proper accounting for factors and covariates affecting milk yields is equally crucial.
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In the United States, lactation milk yields are not measured directly but are calculated from the test-day milk yields. Still, test-day milk yields are estimated from partial yields obtained from single milkings. Various methods have been proposed to estimate test-day milk yields, primarily to deal with unequal milking intervals dating back to the 1970s and 1980s. The Wiggans model is a de facto method for estimating test-day milk yields in the United States, which was initially proposed for cows milked 3 times daily, assuming a linear relationship between a proportional test-day milk yield and milking interval. However, the linearity assumption did not hold precisely in Holstein cows milked twice daily because of prolonged and uneven milking intervals. The present study reviewed and evaluated the nonlinear models that extended the Wiggans model for estimating daily or test-day milk yields. These nonlinear models, except step functions, demonstrated smaller errors and greater accuracies for estimated test-day milk yields compared with the conventional methods. The nonlinear models offered additional benefits. For example, the locally weighted regression model (e.g., locally estimated scatterplot smoothing) could utilize data information in scalable neighborhoods and weigh observations according to their distance in milking interval time. General additive models provide a flexible, unified framework to model nonlinear predictor variables additively. Another drawback of the conventional methods is a loss of accuracy caused by discretizing milking interval time into large bins while deriving multiplicative correction factors for estimating test-day milk yields. To overcome this problem, we proposed a general approach that allows milk yield correction factors to be derived for every possible milking interval time, resulting in more accurately estimated test-day milk yields. This approach can be applied to any model, including nonparametric models.
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Indústria de Laticínios , Leite , Feminino , Bovinos , Animais , Fatores de Tempo , Indústria de Laticínios/métodos , Lactação , Dinâmica não LinearRESUMO
(1) Background: Little is known about how left ventricular systolic dysfunction (LVSD) affects functional and clinical outcomes in acute ischemic stroke (AIS) patients undergoing thrombolysis; (2) Methods: A retrospective observational study conducted between 2006 and 2018 included 937 consecutive AIS patients undergoing thrombolysis. LVSD was defined as left ventricular ejection fraction (LVEF) < 50%. Univariate and multivariate binary logistic regression analysis was performed for demographic characteristics. Ordinal shift regression was used for functional modified Rankin Scale (mRS) outcome at 3 months. Survival analysis of mortality, heart failure (HF) admission, myocardial infarction (MI) and stroke/transient ischemic attack (TIA) was evaluated with a Cox-proportional hazards model; (3) Results: LVSD patients in comparison with LVEF ≥ 50% patients accounted for 190 and 747 patients, respectively. LVSD patients had more comorbidities including diabetes mellitus (100 (52.6%) vs. 280 (37.5%), p < 0.001), atrial fibrillation (69 (36.3%) vs. 212 (28.4%), p = 0.033), ischemic heart disease (130 (68.4%) vs. 145 (19.4%), p < 0.001) and HF (150 (78.9%) vs. 46 (6.2%), p < 0.001). LVSD was associated with worse functional mRS outcomes at 3 months (adjusted OR 1.41, 95% CI 1.03-1.92, p = 0.030). Survival analysis identified LVSD to significantly predict all-cause mortality (adjusted HR [aHR] 3.38, 95% CI 1.74-6.54, p < 0.001), subsequent HF admission (aHR 4.23, 95% CI 2.17-8.26, p < 0.001) and MI (aHR 2.49, 95% CI 1.44-4.32, p = 0.001). LVSD did not predict recurrent stroke/TIA (aHR 1.15, 95% CI 0.77-1.72, p = 0.496); (4) Conclusions: LVSD in AIS patients undergoing thrombolysis was associated with increased all-cause mortality, subsequent HF admission, subsequent MI and poorer functional outcomes, highlighting a need to optimize LVEF.
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INTRODUCTION: Single branched thoracic endografts (SBTEs) have been designed for pathology requiring zone 2 seal during thoracic endovascular aortic repair (TEVAR). Numerous criteria must be met to allow for their implantation. Our aim was to analyze anatomic suitability for a next generation SBTE. METHODS: We reviewed 150 TEVAR procedures between 2015 and 2019. Proximal seal was: zone 0 in 21 (16%), zone 1 in 4 (3%), zone 2 in 52 (40%), zone 3 in 45 (35%), and zone 4 or distal in 7 (5%). We analyzed the Zone 2 patient's angiograms and CT angiograms using centerline software to measure arterial diameters and length in relation to the left common carotid artery (LCCA), left subclavian artery (LSA) and proximal extent of aortic disease to determine if patients met anatomic criteria of a novel SBTE. RESULTS: Zone 2 average age was 64.4 ± 16.3 years; 34 patients were male (65%). Indications for repair were aneurysm (N = 9, 17%), acute dissection (N = 14, 27%), chronic dissection with aneurysmal degeneration (N = 7, 13%), intramural hematoma (N = 9, 17%), penetrating aortic ulcer (N = 5, 10%), and blunt traumatic aortic injury (BTAI, N = 8, 15%). LSA revascularization occurred in 27 patients (52%). Overall, 20 (38.5%) of the zone 2 patients met anatomic criteria. Patients with dissection met anatomic criteria less frequently than aneurysm (33% [10 of 30] vs 64% [9 of 14]). Patients treated for BTAI rarely met the anatomic criteria (1 of 8, 13%). The main anatomic constraints were an inadequate distance from the LCCA to the LSA takeoff and from the LCCA to the start of the aortic disease process. CONCLUSION: Less than half of patients who require seal in zone 2 met criteria for this SBTE. Patients with aneurysms met anatomic criteria more often than those with dissection. The device would have little applicability in treating patients with BTAI.
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Aneurisma da Aorta Torácica , Doenças da Aorta , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Prótese Vascular , Correção Endovascular de Aneurisma , Resultado do Tratamento , Estudos Retrospectivos , Stents/efeitos adversos , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/cirurgia , Doenças da Aorta/etiologia , Aortografia/métodos , Artéria Subclávia/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/etiologiaRESUMO
Associations between dietary selenium status and the clinical outcome of many viral infections, including SARS-CoV-2, are well established. Multiple independent studies have documented a significant inverse correlation between selenium status and the incidence and mortality of COVID-19. At the molecular level, SARS-CoV-2 infection has been shown to decrease the expression of certain selenoproteins, both in vitro and in COVID-19 patients. Using computational methods, our group previously identified a set of six host proteins that contain potential SARS-CoV-2 main protease (Mpro) cleavage sites. Here we show experimentally that Mpro can cleave four of the six predicted target sites, including those from three selenoproteins: thioredoxin reductase 1 (TXNRD1), selenoprotein F, and selenoprotein P, as well as the rate-limiting enzyme in glutathione synthesis, glutamate-cysteine ligase catalytic subunit (GCLC). Cleavage was assessed by incubating recombinant SARS-CoV-2 Mpro with synthetic peptides spanning the proposed cleavage sites, and analyzing the products via UPLC-MS. Furthermore, upon incubation of a recombinant Sec498Ser mutant of the full TXNRD1 protein with SARS-CoV-2 Mpro, the predicted cleavage was observed, destroying the TXNRD1 C-terminal redox center. Mechanistically, proteolytic knockdown of both TXNRD1 and GCLC is consistent with a viral strategy to inhibit DNA synthesis, conserving the pool of ribonucleotides for increased virion production. Viral infectivity could also be enhanced by GCLC knockdown, given the ability of glutathione to disrupt the structure of the viral spike protein via disulfide bond reduction. These findings shed new light on the importance of dietary factors like selenium and glutathione in COVID-19 prevention and treatment.