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BACKGROUND: The effects of temporary mechanical circulatory support with a microaxial flow pump on mortality among patients with ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock remains unclear. METHODS: In an international, multicenter, randomized trial, we assigned patients with STEMI and cardiogenic shock to receive a microaxial flow pump (Impella CP) plus standard care or standard care alone. The primary end point was death from any cause at 180 days. A composite safety end point was severe bleeding, limb ischemia, hemolysis, device failure, or worsening aortic regurgitation. RESULTS: A total of 360 patients underwent randomization, of whom 355 were included in the final analysis (179 in the microaxial-flow-pump group and 176 in the standard-care group). The median age of the patients was 67 years, and 79.2% were men. Death from any cause occurred in 82 of 179 patients (45.8%) in the microaxial-flow-pump group and in 103 of 176 patients (58.5%) in the standard-care group (hazard ratio, 0.74; 95% confidence interval [CI], 0.55 to 0.99; P = 0.04). A composite safety end-point event occurred in 43 patients (24.0%) in the microaxial-flow-pump group and in 11 (6.2%) in the standard-care group (relative risk, 4.74; 95% CI, 2.36 to 9.55). Renal-replacement therapy was administered to 75 patients (41.9%) in the microaxial-flow-pump group and to 47 patients (26.7%) in the standard-care group (relative risk, 1.98; 95% CI, 1.27 to 3.09). CONCLUSIONS: The routine use of a microaxial flow pump with standard care in the treatment of patients with STEMI-related cardiogenic shock led to a lower risk of death from any cause at 180 days than standard care alone. The incidence of a composite of adverse events was higher with the use of the microaxial flow pump. (Funded by the Danish Heart Foundation and Abiomed; DanGer Shock ClinicalTrials.gov number, NCT01633502.).
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Coração Auxiliar , Infarto do Miocárdio com Supradesnível do Segmento ST , Choque Cardiogênico , Idoso , Feminino , Humanos , Masculino , Coração Auxiliar/efeitos adversos , Incidência , Choque Cardiogênico/etiologia , Choque Cardiogênico/mortalidade , Choque Cardiogênico/cirurgia , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Resultado do Tratamento , Circulação Assistida/efeitos adversos , Circulação Assistida/instrumentação , Circulação Assistida/métodosRESUMO
Advances in omics technologies have allowed spatially resolved molecular profiling of single cells, providing a window not only into the diversity and distribution of cell types within a tissue, but also into the effects of interactions between cells in shaping the transcriptional landscape. Cells send chemical and mechanical signals which are received by other cells, where they can subsequently initiate context-specific gene regulatory responses. These interactions and their responses shape the individual molecular phenotype of a cell in a given microenvironment. RNAs or proteins measured in individual cells, together with the cells' spatial distribution, provide invaluable information about these mechanisms and the regulation of genes beyond processes occurring independently in each individual cell. "SpaCeNet" is a method designed to elucidate both the intracellular molecular networks (how molecular variables affect each other within the cell) and the intercellular molecular networks (how cells affect molecular variables in their neighbors). This is achieved by estimating conditional independence (CI) relations between captured variables within individual cells and by disentangling these from CI relations between variables of different cells.
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Redes Reguladoras de Genes , Análise de Célula Única , Humanos , Análise de Célula Única/métodos , Genômica/métodos , AnimaisRESUMO
BACKGROUND: In the Danish-German Cardiogenic Shock (DanGer Shock) trial, use of a microaxial flow pump (mAFP) in patients with ST-segment elevation myocardial infarction (STEMI)-related CS led to lower all-cause mortality but higher rates of renal replacement therapy (RRT). In this prespecified analysis, rates and predictors of acute kidney injury (AKI) and RRT were assessed. METHODS: In this international, randomized, open label, multicenter trial, 355 adult patients with STEMI-CS were randomized to mAFP (N=179) or standard care alone (N=176). AKI was defined according to Risk, Injury, and Failure, sustained Loss and End-stage kidney disease (RIFLE) criteria and assessed using logistic regression models. Use of RRT was assessed accounting for the competing risk of death using Fine-Gray subdistribution hazard models. RESULTS: AKI (RIFLE≥1) was recorded in 110 patients (61%) in mAFP group and 79 (45%) in control group (p<0.01); RRT was used in 75 (42%) and 47 (27%) patients, respectively (p<0.01). About 2/3 of the RRTs were initiated within the first 24h from admission (n=48 (64%) in mAFP group, n=31 (66%) in control group). Occurrence of AKI and RRT were associated with higher 180-day mortality in both study arms. At 180 days, all patients alive were free of RRT. mAFP use was associated with higher rates of RRT, even when accounting for competing risk of death (subdistribution hazard: 1.67 [1.18-2.35]). This association was largely consistent among prespecified subgroups. Allocation to mAFP was associated with lower 180-day mortality irrespective of AKI or RRT (p=0.8 for interaction). Relevant predictors of AKI in both groups comprised reduced left ventricular ejection fraction, baseline kidney function, shock severity, bleeding events, and positive fluid balance. In addition, predictors of AKI specific to mAFP were suction events, higher pump speed, and longer duration of support. CONCLUSIONS: Shock severity, allocation to mAFP, and device-related complications were associated with an increased risk of AKI. AKI was generally associated with higher mortality, but the allocation to mAFP consistently led to lower mortality rates at 180 days irrespective of the occurrence of AKI with or without RRT initiation.
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The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) for temporary mechanical circulatory support in various clinical scenarios has been increasing consistently, despite the lack of sufficient evidence regarding its benefit and safety from adequately powered randomized controlled trials. Although the ARREST trial (Advanced Reperfusion Strategies for Patients with Out-of-Hospital Cardiac Arrest and Refractory Ventricular Fibrillation) and a secondary analysis of the PRAGUE OHCA trial (Prague Out-of-Hospital Cardiac Arrest) provided some evidence in favor of VA-ECMO in the setting of out-of-hospital cardiac arrest, the INCEPTION trial (Early Initiation of Extracorporeal Life Support in Refractory Out-of-Hospital Cardiac Arrest) has not found a relevant improvement of short-term mortality with extracorporeal cardiopulmonary resuscitation. In addition, the results of the recently published ECLS-SHOCK trial (Extracorporeal Life Support in Cardiogenic Shock) and ECMO-CS trial (Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock) discourage the routine use of VA-ECMO in patients with infarct-related cardiogenic shock. Ongoing clinical trials (ANCHOR [Assessment of ECMO in Acute Myocardial Infarction Cardiogenic Shock, NCT04184635], REVERSE [Impella CP With VA ECMO for Cardiogenic Shock, NCT03431467], UNLOAD ECMO [Left Ventricular Unloading to Improve Outcome in Cardiogenic Shock Patients on VA-ECMO, NCT05577195], PIONEER [Hemodynamic Support With ECMO and IABP in Elective Complex High-risk PCI, NCT04045873]) may clarify the usefulness of VA-ECMO in specific patient subpopulations and the efficacy of combined mechanical circulatory support strategies. Pending further data to refine patient selection and management recommendations for VA-ECMO, it remains uncertain whether the present usage of this device improves outcomes.
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Oxigenação por Membrana Extracorpórea , Infarto do Miocárdio , Parada Cardíaca Extra-Hospitalar , Intervenção Coronária Percutânea , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Infarto do Miocárdio/etiologia , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/etiologia , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/terapia , Ensaios Clínicos como AssuntoRESUMO
MOTIVATION: The inference of cellular compositions from bulk and spatial transcriptomics data increasingly complements data analyses. Multiple computational approaches were suggested and recently, machine learning techniques were developed to systematically improve estimates. Such approaches allow to infer additional, less abundant cell types. However, they rely on training data which do not capture the full biological diversity encountered in transcriptomics analyses; data can contain cellular contributions not seen in the training data and as such, analyses can be biased or blurred. Thus, computational approaches have to deal with unknown, hidden contributions. Moreover, most methods are based on cellular archetypes which serve as a reference; e.g. a generic T-cell profile is used to infer the proportion of T-cells. It is well known that cells adapt their molecular phenotype to the environment and that pre-specified cell archetypes can distort the inference of cellular compositions. RESULTS: We propose Adaptive Digital Tissue Deconvolution (ADTD) to estimate cellular proportions of pre-selected cell types together with possibly unknown and hidden background contributions. Moreover, ADTD adapts prototypic reference profiles to the molecular environment of the cells, which further resolves cell-type specific gene regulation from bulk transcriptomics data. We verify this in simulation studies and demonstrate that ADTD improves existing approaches in estimating cellular compositions. In an application to bulk transcriptomics data from breast cancer patients, we demonstrate that ADTD provides insights into cell-type specific molecular differences between breast cancer subtypes. AVAILABILITY AND IMPLEMENTATION: A python implementation of ADTD and a tutorial are available at Gitlab and zenodo (doi:10.5281/zenodo.7548362).
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Aprendizado de Máquina , Humanos , Perfilação da Expressão Gênica/métodos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Transcriptoma , Algoritmos , Biologia Computacional/métodos , FemininoRESUMO
PURPOSE: Abscopal effects have been reported predominantly in metastatic cancers, indicating a radiographic response in a lesion that has not been included in the radiotherapy target volume. The response is interpreted as a humoral immune response to radiotherapy-generated tumour-specific antigens. In this case study, we present the first histologically confirmed multifocal low-grade meningioma with spontaneous regression of all other lesions after conventionally fractionated stereotactic radiotherapy (RT). CASE REPORT: Two localisations, right frontal and right spheno-orbital, were resected at the time of the initial diagnosis in a 66-year-old woman. RT was performed 1 year later to a progressive occipital lesion at the cerebral falx. RESULTS: Regular magnetic resonance imaging (MRI) showed slightly decreasing tumour volume in untreated lesions 1 year after RT and continued during further follow-up. Up to >â¯7 years after treatment, MRI demonstrated an almost complete response of all initial lesions. Two prior reports with meningioma were published in one patient with an atypical meningioma after conventionally fractionated RT and another patient with an intracranial meningiomatosis after radiosurgery. CONCLUSION: This case study supports the concepts of treating only progressive or symptomatic meningioma lesions locally and careful regular MRI surveillance for further assessment. Potential active interventions to trigger an abscopal effect are currently not known. Further research of this beneficial effect for our patients should be supported.
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BACKGROUND AND OBJECTIVES: Postoperative delirium is a frequent and severe complication after cardiac surgery. Activity of butyrylcholinesterase (BChE) has been discussed controversially regarding a possible role in its development. This study aimed to investigate the relevance of BChE activity as a biomarker for postoperative delirium after cardiac surgery or percutaneous valve replacement. METHODS: A total of 237 patients who received elective cardiothoracic surgery or percutaneous valve replacement at a tertiary care centre were admitted preoperatively. These patients were tested with the Montreal Cognitive Assessment investigating cognitive deficits, and assessed for postoperative delirium twice daily for three days via the 3D-CAM or the CAM-ICU, depending on their level of consciousness. BChE activity was measured at three defined time points before and after surgery. RESULTS: Postoperative delirium occurred in 39.7% of patients (n = 94). Univariate analysis showed an association of pre- and postoperative BChE activity with its occurrence (p = 0.037, p = 0.001). There was no association of postoperative delirium and the decline in BChE activity (pre- to postoperative, p = 0.327). Multivariable analysis including either preoperative or postoperative BChE activity as well as age, MoCA, type 2 diabetes mellitus, coronary heart disease, type of surgery and intraoperative administration of red-cell concentrates was performed. Neither preoperative nor postoperative BChE activity was independently associated with the occurrence of postoperative delirium (p = 0.086, p = 0.484). Preoperative BChE activity was lower in older patients (B = -12.38 (95% CI: -21.94 to -2.83), p = 0.011), and in those with a history of stroke (B = -516.173 (95% CI: -893.927 to -138.420), p = 0.008) or alcohol abuse (B = -451.47 (95% CI: -868.38 to -34.55), p = 0.034). Lower postoperative BChE activity was independently associated with longer procedures (B = -461.90 (95% CI: -166.34 to -757.46), p = 0.002), use of cardiopulmonary bypass (B = -262.04 (95% CI: -485.68 to -38.39), p = 0.022), the number of administered red cell-concentrates (B = -40.99 (95% CI: -67.86 to -14.12), p = 0.003) and older age (B = -9.35 (95% CI: -16.04 to -2.66), p = 0.006). CONCLUSION: BChE activity is not independently associated with the occurrence of postoperative delirium. Preoperative BChE values are related to patients' morbidity and vulnerability, while postoperative activities reflect the severity, length and complications of surgery.
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Delírio , Diabetes Mellitus Tipo 2 , Delírio do Despertar , Idoso , Humanos , Butirilcolinesterase , Estudos de Coortes , Delírio/epidemiologia , Delírio/etiologia , Diabetes Mellitus Tipo 2/complicações , Delírio do Despertar/complicações , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Fatores de RiscoRESUMO
The Impella device (Impella, Abiomed, Danvers, MA) is a percutaneous transvalvular microaxial flow pump that is currently used for (1) cardiogenic shock, (2) left ventricular unloading (combination of venoarterial extracorporeal membrane oxygenation and Impella concept), (3) high-risk percutaneous coronary interventions, (4) ablation of ventricular tachycardia, and (5) treatment of right ventricular failure. Impella-assisted forward blood flow increased mean arterial pressure and cardiac output, peripheral tissue perfusion, and coronary blood flow in observational studies and some randomized trials. However, because of the need for large-bore femoral access (14 F for the commonly used Impella CP device) and anticoagulation, the incidences of bleeding and ischemic complications are as much as 44% and 18%, respectively. Hemolysis is reported in as many as 32% of patients and stroke in as many as 13%. Despite the rapidly growing use of the Impella device, there are still insufficient data on its effect on outcome and complications on the basis of large, adequately powered randomized controlled trials. The only 2 small and also underpowered randomized controlled trials in cardiogenic shock comparing Impella versus intra-aortic balloon pump did not show improved mortality. Several larger randomized controlled trials are currently recruiting patients or are in preparation in cardiogenic shock (DanGer Shock [Danish-German Cardiogenic Shock Trial; NCT01633502]), left ventricular unloading (DTU-STEMI [Door-To-Unload in ST-Segment-Elevation Myocardial Infarction; NCT03947619], UNLOAD ECMO [Left Ventricular Unloading to Improve Outcome in Cardiogenic Shock Patients on VA-ECMO], and REVERSE [A Prospective Randomised Trial of Early LV Venting Using Impella CP for Recovery in Patients With Cardiogenic Shock Managed With VA ECMO; NCT03431467]) and high-risk percutaneous coronary intervention (PROTECT IV [Impella-Supported PCI in High-Risk Patients With Complex Coronary Artery Disease and Reduced Left Ventricular Function; NCT04763200]).
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Cardiologia , Oxigenação por Membrana Extracorpórea , Coração Auxiliar , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Oxigenação por Membrana Extracorpórea/efeitos adversos , Coração Auxiliar/efeitos adversos , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Choque Cardiogênico , Resultado do TratamentoRESUMO
Gilles de la Tourette syndrome (GTS) is a neuropsychiatric movement disorder with reported abnormalities in various neurotransmitter systems. Considering the integral role of iron in neurotransmitter synthesis and transport, it is hypothesized that iron exhibits a role in GTS pathophysiology. As a surrogate measure of brain iron, quantitative susceptibility mapping (QSM) was performed in 28 patients with GTS and 26 matched controls. Significant susceptibility reductions in the patients, consistent with reduced local iron content, were obtained in subcortical regions known to be implicated in GTS. Regression analysis revealed a significant negative association of tic scores and striatal susceptibility. To interrogate genetic mechanisms that may drive these reductions, spatially specific relationships between susceptibility and gene-expression patterns from the Allen Human Brain Atlas were assessed. Correlations in the striatum were enriched for excitatory, inhibitory, and modulatory neurochemical signaling mechanisms in the motor regions, mitochondrial processes driving ATP production and ironsulfur cluster biogenesis in the executive subdivision, and phosphorylation-related mechanisms affecting receptor expression and long-term potentiation in the limbic subdivision. This link between susceptibility reductions and normative transcriptional profiles suggests that disruptions in iron regulatory mechanisms are involved in GTS pathophysiology and may lead to pervasive abnormalities in mechanisms regulated by iron-containing enzymes.
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Transtornos dos Movimentos , Síndrome de Tourette , Humanos , Síndrome de Tourette/diagnóstico por imagem , Síndrome de Tourette/genética , Transcriptoma , Encéfalo/diagnóstico por imagem , HomeostaseRESUMO
We report a state-of-the-art lattice QCD calculation of the isovector quark transversity distribution of the proton in the continuum and physical mass limit using large-momentum effective theory. The calculation is done at four lattice spacings a={0.098,0.085,0.064,0.049} fm and various pion masses ranging between 220 and 350 MeV, with proton momenta up to 2.8 GeV. The result is nonperturbatively renormalized in the hybrid scheme with self-renormalization, which treats the infrared physics at large correlation distance properly, and extrapolated to the continuum, physical mass, and infinite momentum limit. We also compare with recent global analyses for the nucleon isovector quark transversity distribution.
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Surface modification of indium tin oxide (ITO) electrodes with organic molecules is known to tune their work function which results in higher charge carrier selectivity in corresponding organic electronic devices and hence influences the performance of organic solar cells. In recent years, N-heterocyclic carbenes (NHCs) have also been proven to be capable to modify the work function of metals and semimetals compared to the unfunctionalized surface via the formation of strong covalent bonds. In this report, we have designed and performed the modification of the ITO surface with NHC by using the zwitterionic bench stable IPr-CO2 as the NHC precursor, applied via spin coating. Upon modification, the work function of ITO electrodes was reduced significantly which resulted in electron selective contacts in corresponding organic photovoltaic devices. In addition, various characterization techniques and analytical methods are used to elucidate the nature of the bound species and the corresponding binding mechanism of the material to the ITO surface.
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BACKGROUND: Intensive Care Unit (ICU) survivors often experience several impairments in their physical, cognitive, and psychological health status, which are labeled as post-intensive care syndrome (PICS). The aim of this work is to develop a multidisciplinary and -professional guideline for the rehabilitative therapy of PICS. METHODS: A multidisciplinary/-professional task force of 15 healthcare professionals applied a structured, evidence-based approach to address 10 scientific questions. For each PICO-question (Population, Intervention, Comparison, and Outcome), best available evidence was identified. Recommendations were rated as "strong recommendation", "recommendation" or "therapy option", based on Grading of Recommendations, Assessment, Development and Evaluation principles. In addition, evidence gaps were identified. RESULTS: The evidence resulted in 12 recommendations, 4 therapy options, and one statement for the prevention or treatment of PICS. RECOMMENDATIONS: early mobilization, motor training, and nutrition/dysphagia management should be performed. Delirium prophylaxis focuses on behavioral interventions. ICU diaries can prevent/treat psychological health issues like anxiety and post-traumatic stress disorders. Early rehabilitation approaches as well as long-term access to specialized rehabilitation centers are recommended. Therapy options include additional physical rehabilitation interventions. Statement: A prerequisite for the treatment of PICS are the regular and repeated assessments of the physical, cognitive and psychological health in patients at risk for or having PICS. CONCLUSIONS: PICS is a variable and complex syndrome that requires an individual multidisciplinary, and multiprofessional approach. Rehabilitation of PICS should include an assessment and therapy of motor-, cognitive-, and psychological health impairments.
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Cuidados Críticos , Unidades de Terapia Intensiva , Humanos , Cuidados Críticos/psicologia , Nível de Saúde , Estado Terminal/psicologiaRESUMO
A growing body of evidence indicates that the benefits of temporary mechanical circulatory support (tMCS) in patients with cardiogenic shock (CS) is dependent on its aetiology and timing of implantation. As such, appropriate diagnosis, screening, selection, and treatment is crucial to achieving good outcomes with tMCS. Here, the latest guidance on CS phenotypes and diagnostics for correctly identifying tMCS candidates is discussed. This includes comprehensive overviews of patient screening with attention given to differences in CS presentation between the sexes, and contraindications for mechanical circulatory support.
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The COVID-19 pandemic had a dramatic impact on aviation in 2020, and the industry's future is uncertain. In this paper, we consider scenarios for recovery and ongoing demand, and discuss the implications of these scenarios for aviation emissions-related policy, including the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) and the EU Emissions Trading Scheme (ETS). Using the Aviation Integrated Model (AIM2015), a global aviation systems model, we project how long-term demand, fleet, and emissions projections might change. Depending on recovery scenario, we project cumulative aviation fuel use to 2050 might be up to 9% below that in scenarios not including the pandemic. The majority of this difference arises from reductions in relative global income levels. Around 40% of modeled scenarios project no offset requirement in either the CORSIA pilot or first phases; however, because of its more stringent emissions baseline (based on reductions from year 2004-2006 CO2, rather than constant year-2019 CO2), the EU ETS is likely to be less affected. However, if no new policies are applied and technology developments follow historical trends, year-2050 global net aviation CO2 is still likely to be well above industry goals, including the goal of carbon-neutral growth from 2019, even when the demand effects of the pandemic are accounted for.
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BACKGROUND: Despite continuous improvements in transcatheter aortic valve implantation (TAVI), periprocedural strokes remain a devastating complication. Randomized controlled trials failed to demonstrate a reduction in clinically apparent strokes or mortality after TAVI due to cerebral embolic protection (CEP). To identify potential targets of CEP strategies during TAVI, we evaluated affected brain regions, and temporal patterns of stroke onset in a routine clinical sample. METHODS AND RESULTS: A total of 3,164 consecutive patients treated with TAVI from 2008 to 2019 at a single center were screened for cerebrovascular events. Affected cerebral regions were determined according to clinical symptoms and brain imaging. Rates of disabling stroke and non-disabling stroke at 30 days were 2.2% and 1.4%, respectively. The frequency of all strokes decreased from 5.0% to 3.0% over time (P = .012). Patients with impaired left-ventricular function (OR 2.19), increased CHA2DS2-VASc (OR 1.39) and moderate/severe spontaneous echo contrast (OR 3.60) had a higher stroke risk. Acute symptom onset occurred during TAVI (19.4%), within 24 hours (40.3%) or later (25.0%); 98.3% of strokes were of ischemic origin. In intraprocedural strokes, 53.2% of lesions were found in locations considered protected by current CEP devices, and 37.5% of patients with intraprocedural strokes were exclusively affected in these areas. Baseline or procedural parameters were not associated with embolic distribution patterns. CONCLUSIONS: Most strokes occurred early after TAVI - but not necessarily during the procedure - and affected multiple brain regions only partially protected by current CEP devices. Efficient prevention of cerebrovascular events may require strategies beyond the TAVI procedure to minimize stroke risk and additional randomized controlled trials will be required to clarify the role of CEP in efficient stroke prevention during TAVI.
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Estenose da Valva Aórtica , Dispositivos de Proteção Embólica , Implante de Prótese de Valva Cardíaca , Embolia Intracraniana , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Valva Aórtica/cirurgia , Encéfalo/diagnóstico por imagem , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Embolia Intracraniana/epidemiologia , Embolia Intracraniana/etiologia , Embolia Intracraniana/prevenção & controle , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do TratamentoRESUMO
We present a state-of-the-art lattice QCD calculation of the pion and kaon light-cone distribution amplitudes (DAs) using large-momentum effective theory. The calculation is done at three lattice spacings a≈{0.06,0.09,0.12} fm and physical pion and kaon masses, with the meson momenta P_{z}={1.29,1.72,2.15} GeV. The result is nonperturbatively renormalized in a recently proposed hybrid scheme with self-renormalization, and extrapolated reliably to the continuum as well as the infinite momentum limit. We find a significant deviation of the pion and kaon DAs from the asymptotic form, and a large SU(3) flavor breaking effect in the kaon DA.
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PURPOSE: Interstitial brachytherapy for pulmonary tumours is an alternative to stereotactic radiotherapy, allowing high conformity despite it being an invasive technique. The aim of the study was the analysis of dose distribution, toxicity and tumour response rates. METHODS: In the years 2014-2019, 27 patients with pulmonary tumours received 36 interstitial brachytherapies with Ir-192: 11 patients with non-small cell lung cancer, 16 patients with pulmonary metastases of other entities. RESULTS: Patients were treated with a median (interquartile range) prescription dose of 20 (20-26)â¯Gy in a single fraction. Mean lung dose to the ipsilateral lung was 2.8 (1.6-4.7)â¯Gy. Maximum doses to the heart, oesophagus, thoracic wall and spinal cord were 2.4 (1.8-4.6)â¯Gy, 2.0 (1.2-6.2)â¯Gy, 12.6 (8.0-18.2)â¯Gy and 1.5 (0.6-3.9)â¯Gy. Median survival after treatment was 15 months, with a 1- and 2year local control of 84% and 60%. Median overall survival after initial cancer diagnosis was 94 months; 2 years following brachytherapy, 75% of patients with colorectal cancer vs. 37% with other histologies were alive; pâ¯= 0.14. In 69% (nâ¯= 25), brachytherapy could be performed without acute complications. A self-limiting bleeding occurred in 8% (nâ¯= 3), fever in 3% (nâ¯= 1), pneumothorax in 17% (nâ¯= 6), and pulmonary failure in 3% (nâ¯= 1). Patients with >â¯20â¯Gy in 95% of planning target volume had higher pneumothorax rates needing intervention (31% vs. 5%, pâ¯= 0.04). CONCLUSIONS: Interstitial brachytherapy for pulmonary tumours is a highly conformal therapy with minimal doses to the organs at risk. For the majority of patients, treatment can be performed without relevant complications in a single fraction with a satisfactory local control.
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Braquiterapia/métodos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Adenocarcinoma/radioterapia , Adenocarcinoma/secundário , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Neoplasias Colorretais , Relação Dose-Resposta à Radiação , Esôfago/efeitos da radiação , Feminino , Coração/efeitos da radiação , Hemorragia/etiologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Órgãos em Risco , Pneumotórax/etiologia , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem , Sarcoma/radioterapia , Sarcoma/secundário , Medula Espinal/efeitos da radiação , Parede Torácica/efeitos da radiaçãoRESUMO
Alkylating reagents based on thioimidazolium ionic liquids were synthesized and the influence of the anion on the alkylation reaction mechanism explored in detail using both experimental and computational methods. Thioimidazolium cations transfer alkyl substituents to nucleophiles, however the reaction rate was highly dependent on anion identity, demonstrating that the anion is not innocent in the mechanism. Detailed analysis of the computationally-derived potential energy surfaces associated with possible mechanisms indicated that this dependence arises from a combination of anion induced electronic, steric and coordinating effects, with highly nucleophilic anions catalyzing a 2-step process while highly non-nucleophilic, delocalized anions favor a 1-step reaction. This work also confirms the presence of ion-pairs and aggregates in solution thus supporting anion-induced control over the reaction rate and mechanism. These findings provide new insight into an old reaction allowing for better design of cationic alkylators in synthesis, gene expression, polymer science, and protein chemistry applications.
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Insufficient and heterogeneous oxygen (O2) distribution within engineered tissues results in hypoxic conditions. Hypoxia is one of the characteristics of solid tumors. To date, very few studies have used an O2-deliverable injectable hydrogel for cancer treatment under hypoxic conditions. In this field, we describe a new O2-carrying nanomaterial and an injectable nanocomposite hydrogel (PMOF and AlgL-PMOF, respectively) that can provide extended oxygen levels for cell survival under hypoxia. Particularly, PMOF and AlgL-PMOF enhance cell viability under hypoxic and normoxic cell culturing conditions. Moreover, sustained oxygen availability in the presence of an anticancer drug within the 3D network of AlgL-PMOF results in a decrease in the viability of malignant and immortal cells, while the viability of healthy cells increases.
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Hipóxia , Oxigênio , Hipóxia Celular , Sobrevivência Celular , Humanos , Hidrogéis/farmacologia , Nanogéis , Impressão TridimensionalRESUMO
Cardiogenic shock is still a major driver of mortality on intensive care units and complicates â¼10% of acute coronary syndromes with contemporary mortality rates up to 50%. In the meantime, percutaneous circulatory support devices, in particular venoarterial extracorporeal membrane oxygenation (VA-ECMO), have emerged as an established salvage intervention for patients in cardiogenic shock. Venoarterial extracorporeal membrane oxygenation provides temporary circulatory support until other treatments are effective and enables recovery or serves as a bridge to ventricular assist devices, heart transplantation, or decision-making. In this critical care perspective, we provide a concise overview of VA-ECMO utilization in cardiogenic shock, considering rationale, critical care management, as well as weaning aspects. We supplement previous literature by focusing on therapeutic issues related to the vicious circle of retrograde aortic VA-ECMO flow, increased left ventricular (LV) afterload, insufficient LV unloading, and severe pulmonary congestion limiting prognosis in a relevant proportion of patients receiving VA-ECMO treatment. We will outline different modifications in percutaneous mechanical circulatory support to meet this challenge. Besides a strategy of running ECMO at lowest possible flow rates, novel therapeutic options including the combination of VA-ECMO with percutaneous microaxial pumps or implementation of a venoarteriovenous-ECMO configuration based on an additional venous cannula supplying towards pulmonary circulation are most promising among LV unloading and venting strategies. The latter may even combine the advantages of venovenous and venoarterial ECMO therapy, providing potent respiratory and circulatory support at the same time. However, whether VA-ECMO can reduce mortality has to be evaluated in the urgently needed, ongoing prospective randomized studies EURO-SHOCK (NCT03813134), ANCHOR (NCT04184635), and ECLS-SHOCK (NCT03637205). These studies will provide the opportunity to investigate indication, mode, and effect of LV unloading in dedicated sub-analyses. In future, the Heart Teams should aim at conducting a dedicated randomized trial comparing VA-ECMO support with vs. without LV unloading strategies in patients with cardiogenic shock.