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We assessed the impact of donor multiorgan procurement on survival following orthotopic heart transplantation (OHT). From the UNOS STAR database, we included all adult (≥18 Y) heart transplants (OHT) performed since 2000 and used donor IDs to determine how many other organs were procured from the same donor as the recipient's heart allograft (regardless of recipient). The Kaplan-Meier survival functions and risk-adjusted Cox proportional hazards regression models were computed to assess the association of multiorgan procurement with post-heart transplantation mortality. We included 40 336 OHT patients. Including the heart, the median number of donor organs procured was 3 (IQR, 3-4). Heart donors underwent liver procurement in 89.7%; kidney(s) in 98.1% (single 95%, bilateral 5%); lung(s) in 38.0% (single 28%, bilateral 72%); pancreas in 10.4%; and intestine in 1.6%. Following risk adjustment across 16 recipient- and donor-specific variables, an increasing number of organs procured were independently associated with reduced post-OHT mortality (HR 0.98, 95% CI 0.96-0.99, P = .025). Though no significant associations were found examining specific organ types, double lung procurement trended toward a protective effect (HR 0.96, 0.92-1.01, P = .086), with counts of non-lung organs procured still bordering on significance (HR 0.97, 95% CI 0.95-1.00, P = .067). These results likely reflect improved multiorgan donor quality.
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Transplante de Coração , Obtenção de Tecidos e Órgãos , Transplantes , Adulto , Bases de Dados Factuais , Sobrevivência de Enxerto , Humanos , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Doadores de TecidosRESUMO
In the Siemens method, high-purity Si is produced by reducing SiHCl3 source gas with H2 ambient under atmospheric pressure. Since the pyrolysis of SiHCl3, which produces SiCl4 as a byproduct, occurs dominantly in the practical Siemens process, the Si yield is low (~30%). In the present study, we generated hydrogen radicals (H-radicals) at pressures greater than 1 atm using tungsten filaments and transported the H-radicals into a reactor. On the basis of the absorbance at 600 nm of WO3-glass exposed to H-radicals in the reactor, we observed that H-radicals with a density of ~1.1 × 1012 cm-3 were transported approximately 30 cm under 1 atm. When SiCl4 was supplied as a source into the reactor containing H-radicals and allowed to react at 850°C or 900°C, Si was produced more efficiently than in reactions conducted under H2 ambient. Because the H-radicals can effectively reduce SiCl4, which is a byproduct in the Siemens method, their use is expected to increase the Si yield for this method.
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RATIONALE: Primary graft dysfunction (PGD) is a form of acute lung injury that occurs after lung transplantation. The definition of PGD was standardized in 2005. Since that time, clinical practice has evolved, and this definition is increasingly used as a primary endpoint for clinical trials; therefore, validation is warranted. OBJECTIVES: We sought to determine whether refinements to the 2005 consensus definition could further improve construct validity. METHODS: Data from the Lung Transplant Outcomes Group multicenter cohort were used to compare variations on the PGD definition, including alternate oxygenation thresholds, inclusion of additional severity groups, and effects of procedure type and mechanical ventilation. Convergent and divergent validity were compared for mortality prediction and concurrent lung injury biomarker discrimination. MEASUREMENTS AND MAIN RESULTS: A total of 1,179 subjects from 10 centers were enrolled from 2007 to 2012. Median length of follow-up was 4 years (interquartile range = 2.4-5.9). No mortality differences were noted between no PGD (grade 0) and mild PGD (grade 1). Significantly better mortality discrimination was evident for all definitions using later time points (48, 72, or 48-72 hours; P < 0.001). Biomarker divergent discrimination was superior when collapsing grades 0 and 1. Additional severity grades, use of mechanical ventilation, and transplant procedure type had minimal or no effect on mortality or biomarker discrimination. CONCLUSIONS: The PGD consensus definition can be simplified by combining lower PGD grades. Construct validity of grading was present regardless of transplant procedure type or use of mechanical ventilation. Additional severity categories had minimal impact on mortality or biomarker discrimination.
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Causas de Morte , Transplante de Pulmão/efeitos adversos , Disfunção Primária do Enxerto/mortalidade , Disfunção Primária do Enxerto/patologia , Adulto , Biomarcadores/análise , Estudos de Coortes , Consenso , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Transplante de Pulmão/métodos , Transplante de Pulmão/mortalidade , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida , Fatores de Tempo , Estados Unidos , Adulto JovemRESUMO
Magnetic microspheres in a concentrated suspension can be self-assembled to form chain structures under a magnetic field, resulting in an enhanced viscosity and elasticity of the suspension (i.e., the magnetorheological (MR) effect). Recently, interest has been raised about the relationship between nonspherical particles, such as octahedral particles and the MR effect. However, experimental studies have not made much progress toward clarifying this issue due to the difficulty associated with synthesizing microparticles with well-defined shapes and sizes. Here, we presented a method for the shape-controlled synthesis of magnetite (Fe3O4) microparticles and investigated the MR effects of two suspensions prepared from the two shape-controlled samples of Fe3O4 microparticles. Our method, which was based on the polyol method, enabled the preparation of spherical and octahedral Fe3O4 microparticles with similar sizes and magnetic properties, through a reduction of α-FeOOH in a mixed solvent of ethylene glycol (a polyol) and water. The water played an important role in both the phase transition (α-FeOOH to Fe3O4) and the shape control. No substantial difference in the MR effect was observed between an octahedral-particle-based suspension and a spherical-particle-based one. Therefore, in this study, the shape of the microparticles did not strongly influence the MR effect, i.e., the properties of the chain structures.
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Micropartículas Derivadas de Células/química , Óxido Ferroso-Férrico/síntese química , Nanopartículas de Magnetita/química , Microesferas , Etilenoglicol/química , Óxido Ferroso-Férrico/química , Campos Magnéticos , Tamanho da Partícula , ViscosidadeRESUMO
BACKGROUND: Acute respiratory distress syndrome (ARDS) is a severe form of lung injury characterized by damage to the epithelial barrier with subsequent pulmonary edema and hypoxic respiratory failure. ARDS is a significant medical problem in intensive care units with associated high care costs. There are many potential causes of ARDS; however, alveolar injury associated with mechanical ventilation, termed ventilator-induced lung injury (VILI), remains a well-recognized contributor. It is thus critical to understand the mechanism of VILI. Based on our published preliminary data, we hypothesized that the endoplasmic reticulum (ER) stress response molecule Protein Kinase R-like Endoplasmic Reticulum Kinase (PERK) plays a role in transmitting mechanosensory signals the alveolar epithelium. METHODS: ER stress signal responses to mechanical stretch were studied in ex-vivo ventilated pig lungs. To explore the effect of PERK inhibition on VILI, we ventilated live rats and compared lung injury parameters to non-ventilated controls. The effect of stretch-induced epithelial ER Ca2+ signaling on PERK was studied in stretched alveolar epithelial monolayers. To confirm the activation of PERK in human disease, ER stress signaling was compared between ARDS and non-ARDS lungs. RESULTS: Our studies revealed increased PERK-specific ER stress signaling in response to overstretch. PERK inhibition resulted in dose-dependent improvement of alveolar inflammation and permeability. Our data indicate that stretch-induced epithelial ER Ca2+ release is an activator of PERK. Experiments with human lung tissue confirmed PERK activation by ARDS. CONCLUSION: Our study provides evidences that PERK is a mediator stretch signals in the alveolar epithelium.
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Estresse do Retículo Endoplasmático/fisiologia , Pulmão/metabolismo , Receptores Pulmonares de Alongamento/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , eIF-2 Quinase/fisiologia , Adulto , Idoso , Animais , Feminino , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Receptores Pulmonares de Alongamento/patologia , Ratos , Ratos Sprague-Dawley , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Suínos , Lesão Pulmonar Induzida por Ventilação Mecânica/patologiaRESUMO
Obesity is a risk factor for primary graft dysfunction (PGD), a form of lung injury resulting from ischemia-reperfusion after lung transplantation, but the impact of ischemia-reperfusion on adipose tissue is unknown. We evaluated differential gene expression in thoracic visceral adipose tissue (VAT) before and after lung reperfusion. Total RNA was isolated from thoracic VAT sampled from six subjects enrolled in the Lung Transplant Body Composition study before and after allograft reperfusion and quantified using the Human Gene 2.0 ST array. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed enrichment for genes involved in complement and coagulation cascades and Jak-STAT signaling pathways. Overall, 72 genes were upregulated and 56 genes were downregulated in the postreperfusion time compared with baseline. Long pentraxin-3, a gene and plasma protein previously associated with PGD, was the most upregulated gene (19.5-fold increase, p = 0.04). Fibronectin leucine-rich transmembrane protein-3, a gene associated with cell adhesion and receptor signaling, was the most downregulated gene (4.3-fold decrease, p = 0.04). Ischemia-reperfusion has a demonstrable impact on gene expression in visceral adipose tissue in our pilot study of nonobese, non-PGD lung transplant recipients. Future evaluation will focus on differential adipose tissue gene expression and the development of PGD after transplant.
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Tecido Adiposo/metabolismo , Proteína C-Reativa/genética , Transplante de Pulmão/efeitos adversos , Proteínas de Membrana/genética , Obesidade/fisiopatologia , Disfunção Primária do Enxerto/etiologia , Componente Amiloide P Sérico/genética , Transcriptoma , Tecido Adiposo/patologia , Adulto , Idoso , Aloenxertos , Biomarcadores/metabolismo , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Glicoproteínas de Membrana , Projetos Piloto , Disfunção Primária do Enxerto/patologia , Prognóstico , Estudos Prospectivos , Reperfusão , Fatores de RiscoRESUMO
A salicylaldehyde derivative bearing four pyridine arms, 3,5-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-2,4-dihydroxybenzaldehyde (Hbpsal) as a "socket", was prepared and used to derive a series of zinc complexes with various extra anions "plugged" into their vacant site. The crystal structure and 1 Hâ NMR spectra were noticeably influenced by the extra anions, allowing fine-tuning of the properties by "plug-and-socket"-type modification. Similar to unsubstituted salicylaldehyde, the zinc complexes reacted with primary amines to afford Schiff-base compounds. Because of the potential chirality around the coordination sphere, reaction with a chiral amine resulted in an equilibrium system between diastereomers, the potential of which as chiral sources tunable by the extra anions is discussed. Some of the complexes were further converted into zinc- or nickel-salphen (=N,N-bis(salicylidene)-1,2-phenylenediamine) complexes. The electrochemical properties of the nickel complex were slightly modified by the extra anions, whereas the photophysical properties of the zinc complex appeared unchanged.
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As an extension of combinatorial molecular layer epitaxy via ablation of perovskite oxides by a pulsed excimer laser, we have developed a laser molecular beam epitaxy (MBE) system for parallel integration of nano-scaled thin films of organic-inorganic hybrid materials. A pulsed infrared (IR) semiconductor laser was adopted for thermal evaporation of organic halide (A-site: CH3NH3I) and inorganic halide (B-site: PbI2) powder targets to deposit repeated A/B bilayer films where the thickness of each layer was controlled on molecular layer scale by programming the evaporation IR laser pulse number, length, or power. The layer thickness was monitored with an in situ quartz crystal microbalance and calibrated against ex situ stylus profilometer measurements. A computer-controlled movable mask system enabled the deposition of combinatorial thin film libraries, where each library contains a vertically homogeneous film with spatially programmable A- and B-layer thicknesses. On the composition gradient film, a hole transport Spiro-OMeTAD layer was spin-coated and dried followed by the vacuum evaporation of Ag electrodes to form the solar cell. The preliminary cell performance was evaluated by measuring I-V characteristics at seven different positions on the 12.5 mm × 12.5 mm combinatorial library sample with seven 2 mm × 4 mm slits under a solar simulator irradiation. The combinatorial solar cell library clearly demonstrated that the energy conversion efficiency sharply changes from nearly zero to 10.2% as a function of the illumination area in the library. The exploration of deposition parameters for obtaining optimum performance could thus be greatly accelerated. Since the thickness ratio of PbI2 and CH3NH3I can be freely chosen along the shadow mask movement, these experiments show the potential of this system for high-throughput screening of optimum chemical composition in the binary film library and application to halide perovskite solar cell.
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Lesão Pulmonar Aguda/genética , Transplante de Pulmão , Pulmão/metabolismo , Proteínas NLR/genética , Disfunção Primária do Enxerto/genética , Receptores Toll-Like/genética , Transcriptoma , Transplantes/metabolismo , Adulto , Idoso , Biópsia , Estudos de Coortes , Aprendizado Profundo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Transdução de Sinais/genética , Obtenção de Tecidos e ÓrgãosRESUMO
Ventricular septal defect (VSD) after myocardial infarction (MI) is an uncommon but serious complication. Patients refractory to attempts at medical stabilization and requiring emergency surgery have expected mortality rates greater than 50%. We present three cases of extracorporeal membrane oxygenation bridge to surgical repair in patients with multisystem organ failure who would otherwise require emergent cardiac surgery with associated risk and review the literature for mechanical circulatory support for patients with anterior and posterior post-MI VSD.
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Oxigenação por Membrana Extracorpórea , Comunicação Interventricular/etiologia , Comunicação Interventricular/terapia , Infarto do Miocárdio/complicações , Cuidados Pré-Operatórios , Idoso , Oxigenação por Membrana Extracorpórea/métodos , Comunicação Interventricular/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
Primary graft dysfunction (PGD) is a syndrome encompassing a spectrum of mild to severe lung injury that occurs within the first 72 hours after lung transplantation. PGD is characterized by pulmonary edema with diffuse alveolar damage that manifests clinically as progressive hypoxemia with radiographic pulmonary infiltrates. In recent years, new knowledge has been generated on risks and mechanisms of PGD. Following ischemia and reperfusion, inflammatory and immunological injury-repair responses appear to be key controlling mechanisms. In addition, PGD has a significant impact on short- and long-term outcomes; therefore, the choice of donor organ is impacted by this potential adverse consequence. Improved methods of reducing PGD risk and efforts to safely expand the pool are being developed. Ex vivo lung perfusion is a strategy that may improve risk assessment and become a promising platform to implement treatment interventions to prevent PGD. This review details recent updates in the epidemiology, pathophysiology, molecular and genetic biomarkers, and state-of-the-art technical developments affecting PGD.
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Lesão Pulmonar Aguda/etiologia , Transplante de Pulmão/métodos , Disfunção Primária do Enxerto/fisiopatologia , Lesão Pulmonar Aguda/epidemiologia , Lesão Pulmonar Aguda/fisiopatologia , Animais , Biomarcadores/metabolismo , Marcadores Genéticos , Humanos , Disfunção Primária do Enxerto/epidemiologia , Disfunção Primária do Enxerto/prevenção & controle , Medição de Risco/métodos , Índice de Gravidade de Doença , Fatores de Tempo , Obtenção de Tecidos e Órgãos/métodosRESUMO
Objective: To assess the effect of intraoperative cryoablation on postoperative patient-reported pain, opioid use, and clinical outcomes in lung transplantation. Methods: We performed a single-center retrospective cohort study of adult lung transplant recipients from August 2017 to September 2018. We compared outcomes of patients who received intraoperative cryoablation of the intercostal nerves with those who did not. Primary outcomes were postoperative patient-reported pain scores and opioid use. Secondary outcomes included postoperative sedation and agitation levels and perioperative outcomes. Data were abstracted from patients' electronic health records. Results: Of the 102 patients transplanted, 45 received intraoperative cryoablation (intervention group) and 57 received the standard of care, which did not include intercostal or serratus blocks or immediate postoperative epidural placement (control group). The intervention group had significantly lower median and maximum postoperative pain scores at days 3 and 7 and significantly lower oral opioid use at days 3, 7, and 14 compared with the control group. Chronic opioid use at 3 and 6 months' posttransplant was lower in the intervention group. Differences in perioperative outcomes, including length of mechanical ventilation, sedation and agitation levels, and hospital stay, were not clinically meaningful. Survival at 30 days and 1 year was superior in the intervention compared with the control group. Conclusions: Findings suggest that use of intraoperative cryoablation is an effective approach for treating pain and reducing opioid use in patients who undergo lung transplant, but a randomized study across multiple institutions is needed to confirm these findings.
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BACKGROUND: Understanding the degree of motor paralysis in stroke patients is important for assessing the severity of functional impairment and predicting functional prognosis. Fugl-MeyerAssessment for the lower extremities (FMA-LE)is a commonly used measure with high reliability and validity, but there is no official translated Japanese version of FMA-LE. OBJECTIVES: This study aimed to develop Japanese FMA-LE and verify its reliability and validity in patients with acute stroke. METHODS: The Japanese FMA-LE was developed following a standardized translation process. The reliability and validity were evaluated in 50 stroke patients at an acute care hospital. Validity was examined by determining the correlation between FMA-LEand Brunnstrom Recovery Stage (BRS), as well as Short Physical Performance Battery (SPPB). Intra-raterand inter-raterrelative reliabilities were evaluated by calculating intra-classcorrelation coefficients (ICCs). Absolute reliability was assessed by determining the standard error of the measurement and minimum detectible change (MDC). Systematic error was also assessed. RESULTS: FMA-LEtotal score was high correlated with BRS (ρ = 0.73,p < .01) and moderately correlated with SPPB (ρ = 0.69,p < .01). For intra-raterreliability, ICC was 0.98 (p < .01), only fixed systematic error was observed (p < .01), and MDC of the FMA-LEtotal score was 1.24. For inter-raterreliability, ICC was 0.98 (p < .01), no systematic error was observed, and MDC of the FMA-LEtotal score was 3.23. CONCLUSIONS: The Japanese FMA-LE was reliable, valid, and useful for evaluating lower extremity function of acute stroke patients.
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Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Japão , Extremidade Inferior , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Extremidade SuperiorRESUMO
SnS2 nanoparticles were synthesized through a simple wet chemical process at room temperature. The SnS2 nanoparticles were approximately spherical in shape and had diameter about 3-4 nm. SnS2-sensitized TiO2 electrodes were fabricated by the immersion of chemically modified TiO2 to well-dispersed SnS2 solution for 72 h (i.e., self-assembly method.) SnS2-sensitized TiO2 electrodes were applied in quantum dot-sensitized solar cells (QDSSCs). Under AM1.5 irradiation with 100 mW/cm2 light intensity (at 1 sun), the short-circuit current density (J(sc)), the open-circuit voltage (V(oc)), the fill factor (FF), and the energy conversion efficiency (eta) were 0.47 mA/cm2, 0.29 V, 0.58 and 0.081%, respectively.
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Fontes de Energia Elétrica , Eletrodos , Nanoestruturas/química , Pontos Quânticos , Energia Solar , Sulfetos/química , Compostos de Estanho/química , Titânio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Nanoestruturas/ultraestrutura , Tamanho da Partícula , SoluçõesRESUMO
SnS-sensitized TiO2 electrodes were applied in quantum dot-sensitized solar cells (QDSSCs) which are environmentally more favorable than conventional Cd or Pb-chalcogenide-sensitized electrodes. SnS nanoparticles were well-distributed over the surface of TiO2 nanoparticles by the successive ionic layer adsorption and reaction (SILAR) method. Deposited SnS nanoparticles had diameter about 3 nm. Under AM1.5 irradiation with 100 mW/cm2 light intensity (at 1 sun), the energy conversion efficiency of obtained cells reached a value of 0.21% (0.25 cm2) at SILAR coating cycles of 5. In addition, the photovoltaic performance was improved by additional ZnS coating on the surface of SnS-sensitized TiO2 electrodes.
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Fontes de Energia Elétrica , Nanotecnologia/instrumentação , Pontos Quânticos , Energia Solar , Sulfetos/química , Compostos de Estanho/química , Titânio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de MateriaisRESUMO
Magnesium dititanate (MgTi2O5, MT2) has been synthesized since the early 1930s. It has the pseudobrookite structure (general formula Me3O5), corresponding to the Mg-enriched artificial endmember of the Fe2TiO5 (pseudobrookite)-FeTi2O5 (ferropseudobrookite)-Mg0.5Fe0.5Ti2O5 (armalcolite) solid solution. Since MgTi2O5 has relativity high thermal stability among pseudobrookite-type phases, it is expected to be a well-balanced low-thermal-expansion material. Here we review both the historical and recent studies on MgTi2O5, particularly on its crystal structure, cation order-disorder, physical properties and synthesis methods.
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Vertically aligned single-crystalline TiO2 rutile nanorod arrays were synthesized on FTO transparent conductive substrates, via the hydrolysis of TiCl4 under the co-existence of amino acid catalysts. Using TiO2 seed nanocrystals (prepared from Ti(IV) ethoxide, calcined at 450 degrees C for 1 h), TiO, rutile nanorod arrays grew at a relatively mild temperature of 95 degrees C for 2 days. The growth speed and morphology of nanorod array were controllable by changing the type and concentration of amino acid. XRD analysis revealed that the TiO2 nanorod arrays were composed of highly crystalline rutile phase even without calcination. Preliminary dye-sensitized solar cell performance was also reported.
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Aminoácidos/química , Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Titânio/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície , TemperaturaRESUMO
BACKGROUND: No clinically validated tool exists to predict in-hospital mortality in patients requiring extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation. We generated a quantitative risk assessment tool for these patients. METHODS: Of 822 patients in the United Network for Organ Sharing (UNOS) database who required ECMO as bridge to lung transplant between 2004 and 2018, 630 were included in the analysis after exclusion for age <18 years, prior transplant, or treatment before 2004. Recipient-specific variables associated with posttransplant in-hospital mortality were incorporated into a multivariable logistic regression model in an automated stepwise fashion. Linear prediction was used to construct the Recipient Stratification Risk Analysis in Bridging Patients to Lung Transplant on ECMO (STABLE) score. K-fold cross-validation provided an unbiased estimate of out-of-sample performance. After further exclusion for University of Pennsylvania patients, the remaining cohort was used for external score validation. An iOS application was developed to aid clinical use. RESULTS: Six recipient-specific, pretransplant variables were translated into a 24-point score. STABLE scores in the United Network for Organ Sharing (UNOS) database ranged from 0 to 21, and each point increased the odds of in-hospital mortality by 22.0% (95% confidence interval, 1.14-1.29, P < .001). K-fold cross-validation yielded a receiver operating characteristic area under the curve of 86.2%. Validation of the STABLE score using our institutional database yielded an area under the curve of 89%. CONCLUSIONS: The STABLE score is a novel, internally cross-validated tool for risk stratification of patients on ECMO as a bridge to transplant. Its predictive power and accuracy may aid clinical decision-making and improve posttransplant outcomes.
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Oxigenação por Membrana Extracorpórea/métodos , Transplante de Pulmão/métodos , Medição de Risco/métodos , Adulto , Idoso , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Transplante de Pulmão/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Estados Unidos/epidemiologiaRESUMO
Non-equilibrium nitrogen DC-arc plasma treatment of a commercial TiO2 anatase nanopowder was examined to obtain nitrogen-doped TiO2. By using a non-thermal discharge at low current (150 mA) and high voltage (1200 V) using pure N2 gas, light yellowish-gray TiO2 powder was successfully obtained within a short period of 5-10 min. XPS and TEM-EELS studies confirmed the existence of doped nitrogen. Due to the relatively mild conditions (plasma power of 180 W), metastable anatase structure and fine crystallite size of TiO2 (ca. 10 nm) were maintained after the plasma treatment. The in-flight powder treatment system used in this study is promising for various type of powder treatment.
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Silica-based carrier is a promising material for recovery of metal and nonmetal contaminants in chemical oxo-precipitation-fluidized bed crystallization (COP-FBC) system. Boron species are an essential element for plant growth and can cause health concerns in human beings at high concentrations in water environments. The composition of thin-film transistor liquid crystal display (TFT-LCD) contains a wide variety of metal oxides and can be tailored as promising functional mesoporous carriers for boron crystallization recovery in the presence of barium ions and hydrogen peroxide. In this study, waste-derived mesoporous aluminosilicate (MAS) nanomaterial in the presence of barium ions and hydrogen peroxide was used as a carrier for sustainable recovery of crystallized boron, a priority wastewaters pollutant. The MAS shows the hierarchically homogeneous distribution of nanostructured aluminosilicate particles with an average size of 12.8 ± 3.6 nm on the surface after the activation with Na2CO3 at 1000 °C. Moreover, the negatively charged surface and the mesoporous structure of MAS enhance the adsorption of Ba2+ onto MAS, and the Langmuir adsorption capacity of 105 mg/g is achieved, which is conducive to the enhancement of the recovery of boron species. Moreover, the recovery efficiency and crystallization ratio of boron by MAS can be up to 84.5 and 93.4%, respectively. The cross-sectional scanning electron microscopy images and the high-temperature X-ray diffraction results confirm the boron recovery mechanism that the negatively charged functional group as well as the mesoporosity of MAS triggers the rapid formation of needle-shaped precipitates of barium peroxoborate, and then converted to barium borate after calcination at 1050 °C. Results obtained in this study clearly demonstrate the possibility of fabricating environmentally benign mesoporous aluminosilicate adsorbents from TFT-LCD waste to sustainably recover and crystallize boron species from water and wastewater in COP-FBC.