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Multifunctional heterogeneous catalysts are an effective strategy to drive chemical cascades, with attendant time, resource and cost efficiencies by eliminating unit operations arising in normal multistep processes. Despite advances in the design of such catalysts, the fabrication of proximate, chemically antagonistic active sites remains a challenge for inorganic materials science. Hydrogen-bonded organocatalysts offer new opportunities for the molecular level design of multifunctional structures capable of stabilising antagonistic active sites. We report the catalytic application of a charge-assisted, hydrogen-bonded crystalline material, bis(melaminium)adipate (BMA), synthesised from melamine and adipic acid, which possesses proximate acid-base sites. BMA exhibits high activity for the cascade deacetalisation-Knoevenagel condensation of dimethyl acetals to form benzylidenemalononitriles under mild conditions in water; BMA is amenable to large-scale manufacture and recycling with minimal deactivation. Computational modelling of the melaminium cation in protonated BMA explains the observed catalytic reactivity, and identifies the first demethoxylation step as rate-limiting, in good agreement with time-dependent 1H NMR and kinetic experiments. A broad substrate scope for the cascade transformation of aromatic dimethyl acetals is demonstrated.
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Importance: There is a lack of randomized clinical trial (RCT) data to guide many routine decisions in the care of children hospitalized for common conditions. A first step in addressing the shortage of RCTs for this population is to identify the most pressing RCT questions for children hospitalized with common conditions. Objective: To identify the most important and feasible RCT questions for children hospitalized with common conditions. Design, Setting, and Participants: For this consensus statement, a 3-stage modified Delphi process was used in a virtual conference series spanning January 1 to September 29, 2022. Forty-six individuals from 30 different institutions participated in the process. Stage 1 involved construction of RCT questions for the 10 most common pediatric conditions leading to hospitalization. Participants used condition-specific guidelines and reviews from a structured literature search to inform their development of RCT questions. During stage 2, RCT questions were refined and scored according to importance. Stage 3 incorporated public comment and feasibility with the prioritization of RCT questions. Main Outcomes and Measures: The main outcome was RCT questions framed in a PICO (population, intervention, control, and outcome) format and ranked according to importance and feasibility; score choices ranged from 1 to 9, with higher scores indicating greater importance and feasibility. Results: Forty-six individuals (38 who shared demographic data; 24 women [63%]) from 30 different institutions participated in our modified Delphi process. Participants included children's hospital (n = 14) and community hospital (n = 13) pediatricians, parents of hospitalized children (n = 4), other clinicians (n = 2), biostatisticians (n = 2), and other researchers (n = 11). The process yielded 62 unique RCT questions, most of which are pragmatic, comparing interventions in widespread use for which definitive effectiveness data are lacking. Overall scores for importance and feasibility of the RCT questions ranged from 1 to 9, with a median of 5 (IQR, 4-7). Six of the top 10 selected questions focused on determining optimal antibiotic regimens for 3 common infections (pneumonia, urinary tract infection, and cellulitis). Conclusions and Relevance: This consensus statementhas identified the most important and feasible RCT questions for children hospitalized with common conditions. This list of RCT questions can guide investigators and funders in conducting impactful trials to improve care and outcomes for hospitalized children.
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Consenso , Técnica Delphi , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Criança , Hospitalização/estatística & dados numéricos , Feminino , Masculino , Criança Hospitalizada , Pré-Escolar , LactenteRESUMO
BACKGROUND: Human epididymis protein 4 (HE4) is a tumor marker overexpressed in ovarian cancer and is commonly utilized to aid with diagnosis of an adnexal mass. HE4 levels vary based on pregnancy, age, menopausal status, and tobacco use. OBJECTIVE(S): The objective of this study was to evaluate population-based data to examine factors that affect HE4 among adult women in the United States and stratify levels of HE4 by demographic and gynecologic factors. STUDY DESIGN: A retrospective analysis was conducted using data from 2,480 women aged 20 + who participated in the National Health and Nutrition Examination Survey (2001-2002). From these cross-sectional data, serum HE4 and cotinine, a marker of tobacco exposure, were combined with demographic and interview data. Estimated glomerular filtration rates (eGFR) were based on serum creatinine, age, sex, and race. Other variables of interest included menopausal status, pregnancy, and various gynecologic factors. Summary HE4 data are provided as geometric means with associated 95 % confidence intervals. RESULTS: HE4 levels were independently associated with age, renal function, and nicotine use, all p < 0.001. Pre-menopausal women with a history of endometriosis were found to have elevated HE4 levels compared to those without, p < 0.01; however, we found no such difference among post-menopausal women. Adjusting for age, no differences in HE4 were found based on race/ethnicity, p = 0.29. HE4 levels showed statistically significant associations with income level; however, these were small and clinically irrelevant. CONCLUSION: This study provides evaluation of HE4 levels among a data set representative of 98.5 million non-institutionalized women in the United States and gives insight into extraneous factors that may influence these levels.
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Inquéritos Nutricionais , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos , Humanos , Feminino , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos/análise , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos/metabolismo , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia , Estudos Transversais , Proteínas/análise , Proteínas/metabolismo , Adulto Jovem , Gravidez , Idoso , Menopausa/sangue , Fatores EtáriosRESUMO
Evidence suggests an association between exposure to electronic cigarette (e-cigarette) marketing and e-cigarette use (vaping) among adolescents. However, there is limited evidence on exposure to e-cigarette marketing and susceptibility to future vaping, especially among Black and Latino adolescents. This study aimed to examine associations between exposure to e-cigarette marketing and susceptibility to future vaping among Black and Latino adolescents in the United States (US). Participants (N = 362; equal representation between Black and Latino adolescents) completed a baseline assessment (available in English and Spanish) including sociodemographic characteristics (e.g., racial/ethnic group, age, gender, sexual orientation, etc.), exposure to e-cigarette marketing, and susceptibility to future vaping. Exposure to e-cigarette marketing was recoded and organized into two categories (high exposure = 2 to 3; low exposure = 0 to 1). Cochran-Mantel-Haenszel tests were used to evaluate the association between exposure to e-cigarette marketing and susceptibility to future vaping, stratified by racial/ethnic group. Multiple logistic regressions assessed the association between exposure to e-cigarette marketing and susceptibility to future vaping, controlling for gender, sexual orientation, grade, and academic performance within each racial/ethnic group. Black adolescents reported significantly higher frequencies of exposure to e-cigarette marketing (p = 0.005). A significant interaction was found between exposure to e-cigarette marketing and racial/ethnic group (X2 (1) = 6.294, p = 0.012). Among Black adolescents, high exposure to e-cigarette marketing (vs. low exposure) was associated with a higher probability of susceptibility to future vaping (OR: 2.399, 95% CI 1.147-5.021, p = 0.020). For Latino adolescents, exposure to e-cigarette marketing was not associated with susceptibility to future vaping (OR: 0.503, 95% CI 0.245-1.03, p = 0.062). Future studies should evaluate how and where adolescents are exposed to e-cigarette marketing. Prevention efforts must include the implementation of effective counter-marketing campaigns and the reduction of exposure to e-cigarette marketing among Black and Latino adolescents.
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Metal organic frameworks (MOFs) are attractive materials to generate multifunctional catalysts for the electrocatalytic reduction of CO2 to hydrocarbons. Here we report the synthesis of Cu and Zn modified Al-fumarate (Al-fum) MOFs, in which Zn promotes the selective reduction of CO2 to CO and Cu promotes CO reduction to oxygenates and hydrocarbons in an electrocatalytic cascade. Cu and Zn nanoparticles (NPs) were introduced to the Al-fum MOF by a double solvent method to promote in-pore metal deposition, and the resulting reduced Cu-Zn@Al-fum drop-cast on a hydrophobic gas diffusion electrode for electrochemical study. Cu-Zn@Al-fum is active for CO2 electroreduction, with the Cu and Zn loading influencing the product yields. The highest faradaic efficiency (FE) of 62% is achieved at -1.0 V vs. RHE for the conversion of CO2 into CO, HCOOH, CH4, C2H4 and C2H5OH, with a FE of 28% to CH4, C2H4 and C2H5OH at pH 6.8. Al-fum MOF is a chemically robust matrix to disperse Cu and Zn NPs, improving electrocatalyst lifetime during CO2 reduction by minimizing transition metal aggregation during electrode operation.