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1.
Genet Med ; 25(12): 100969, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37634128

RESUMO

PURPOSE: PIK3CA-related overgrowth spectrum (PROS) encompasses several rare conditions resulting from activating variants in PIK3CA. Alpelisib, a PI3Kα-selective inhibitor, targets the underlying etiology of PROS, offering a novel therapeutic approach to current management strategies. This study evaluated the safety and efficacy of alpelisib in pediatric and adult patients with PROS. METHODS: EPIK-P1 (NCT04285723) was a non-interventional, retrospective chart review of 57 patients with PROS (≥2 years) treated with alpelisib through compassionate use. Patients had severe/life-threatening PROS-related conditions and confirmed PIK3CA pathogenic variant. The primary end point assessed patient response to treatment at Week 24 (6 months). RESULTS: Twenty-four weeks (6 months) after treatment initiation, 12 of 32 (37.5%) patients with complete case records included in the analysis of the primary end point experienced a ≥20% reduction in target lesion(s) volume. Additional clinical benefit independent from lesion volume reduction was observed across the full study population. Adverse events (AEs) and treatment-related AEs were experienced by 82.5% (47/57) and 38.6% (22/57) of patients, respectively; the most common treatment-related AEs were hyperglycemia (12.3%) and aphthous ulcer (10.5%). No deaths occurred. CONCLUSION: EPIK-P1 provides real-world evidence of alpelisib effectiveness and safety in patients with PROS and confirms PI3Kα as a valid therapeutic target for PROS symptom management.


Assuntos
Tiazóis , Adulto , Humanos , Criança , Estudos Retrospectivos , Mutação , Tiazóis/efeitos adversos , Classe I de Fosfatidilinositol 3-Quinases/genética
2.
Lancet Oncol ; 22(4): 489-498, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33794206

RESUMO

BACKGROUND: Alpelisib, a PI3Kα-selective inhibitor and degrader, plus fulvestrant showed efficacy in hormone receptor-positive, HER2-negative, PIK3CA-mutated advanced breast cancer in SOLAR-1; limited data are available in the post-cyclin-dependent kinase 4/6 inhibitor setting. BYLieve aimed to assess alpelisib plus endocrine therapy in this setting in three cohorts defined by immediate previous treatment; here, we report results from cohort A. METHODS: This ongoing, phase 2, multicentre, open-label, non-comparative study enrolled patients with hormone receptor-positive, HER2-negative, advanced breast cancer with tumour PIK3CA mutation, following progression on or after previous therapy, including CDK4/6 inhibitors, from 114 study locations (cancer centres, medical centres, university hospitals, and hospitals) in 18 countries worldwide. Participants aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 2 or less, with no more than two previous anticancer treatments and no more than one previous chemotherapy regimen, were enrolled in three cohorts. In cohort A, patients must have had progression on or after a CDK4/6 inhibitor plus an aromatase inhibitor as the immediate previous treatment. Patients received oral alpelisib 300 mg/day (continuously) plus fulvestrant 500 mg intramuscularly on day 1 of each 28-day cycle and on day 15 of cycle 1. The primary endpoint was the proportion of patients alive without disease progression at 6 months per local assessment using Response Evaluation Criteria in Solid Tumors, version 1.1, in patients with a centrally confirmed PIK3CA mutation. This trial is registered with ClinicalTrials.gov, NCT03056755. FINDINGS: Between Aug 14, 2017, and Dec 17, 2019 (data cutoff), 127 patients with at least 6 months' follow-up were enrolled into cohort A. 121 patients had a centrally confirmed PIK3CA mutation. At data cutoff, median follow-up was 11·7 months (IQR 8·5-15·9). 61 (50·4%; 95% CI 41·2-59·6) of 121 patients were alive without disease progression at 6 months. The most frequent grade 3 or worse adverse events were hyperglycaemia (36 [28%] of 127 patients), rash (12 [9%]), and rash maculopapular (12 [9%]). Serious adverse events occurred in 33 (26%) of 127 patients. No treatment-related deaths were reported. INTERPRETATION: BYLieve showed activity of alpelisib plus fulvestrant with manageable toxicity in patients with PIK3CA-mutated, hormone receptor-positive, HER2-negative advanced breast cancer, after progression on a CDK4/6 inhibitor plus an aromatase inhibitor. FUNDING: Novartis Pharmaceuticals.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Classe I de Fosfatidilinositol 3-Quinases/genética , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/genética , Tiazóis/administração & dosagem , Adolescente , Adulto , Idoso , Inibidores da Aromatase/administração & dosagem , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Antagonistas do Receptor de Estrogênio/administração & dosagem , Feminino , Fulvestranto/administração & dosagem , Humanos , Pessoa de Meia-Idade , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Receptores de Estrogênio/genética , Receptores de Progesterona/antagonistas & inibidores , Receptores de Progesterona/genética
3.
Oncologist ; 26(7): e1133-e1142, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33909934

RESUMO

BACKGROUND: The BYLieve trial (NCT03056755) confirmed efficacy and safety of alpelisib with fulvestrant for hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-), PIK3CA-mutated advanced breast cancer (ABC), after cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) with an aromatase inhibitor (AI) as immediate prior therapy. Further analyses were performed to compare efficacy from BYLieve with effectiveness of standard treatment in the real-world setting. MATERIALS AND METHODS: Patients who progressed on a CDK4/6i plus AI and were treated with alpelisib with fulvestrant in BYLieve were matched with a real-world patient cohort who received standard-of-care from a deidentified clinico-genomics database (CGDB). Primary and secondary endpoints were to compare progression-free survival (PFS), estimated by the Kaplan-Meier method, and the proportion of patients remaining progression-free at 6 months, respectively, between the two cohorts. RESULTS: A total of 855 patients with PIK3CA-mutant disease who had prior CDK4/6i plus hormone therapy were selected from the CGDB; further matching to 120 patients from BYLieve selected 95 patients without exposure to HER2-targeting agents, clinical study drug, or alpelisib. In unadjusted and postmatching results, primary and secondary endpoints favored treatment with alpelisib with fulvestrant in BYLieve more than standard treatments in the real-world cohort. Postadjustment, median PFS for patients treated with alpelisib in BYLieve was 7.3 versus 3.7 months in the real-world cohort, and 6-month PFS was 54.6% versus 40.1%, respectively. CONCLUSION: Matched/weighted analysis comparing BYLieve with the real-world setting further supports the clinical benefit of alpelisib with fulvestrant for treatment of HR+, HER2-, PIK3CA-mutant ABC after CDK4/6i treatment. IMPLICATIONS FOR PRACTICE: Approximately 40% of patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) advanced breast cancer (ABC) have PIK3CA-mutated tumors, which have been associated with endocrine therapy resistance. Alpelisib, an α-selective phosphatidylinositol-3-kinase inhibitor, demonstrated significantly improved progression-free survival in SOLAR-1 and demonstrated clinical efficacy in BYLieve when combined with fulvestrant. Data are limited in comparing the efficacy of alpelisib combined with fulvestrant with effectiveness of standard therapy after CDK4/6i treatment. Using real-world data, this is the first analysis comparing alpelisib combined with fulvestrant with standard treatments for HR+, HER2-, PIK3CA-mutant ABC in the post-CDK4/6i setting.


Assuntos
Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/uso terapêutico , Feminino , Fulvestranto/uso terapêutico , Humanos , Receptor ErbB-2/genética , Receptor ErbB-2/uso terapêutico , Receptores de Estrogênio , Tiazóis
4.
BMC Cancer ; 20(1): 53, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964373

RESUMO

BACKGROUND: Study aimed to characterise treatment and outcomes for patients with hormone receptor positive (HR+), human epidermal growth factor 2 negative (HER2-) metastatic breast cancer (MBC) within a large regional cancer centre, as a benchmark for evaluating real-world impact of novel therapies. METHODS: Retrospective longitudinal cohort, using electronic patient records of adult females with a first diagnosis of HR+/HER2- MBC January 2012-March 2018. RESULTS: One hundred ninety-six women were identified with HR+/HER2- MBC. Median age was 67 years, 85.2% were post-menopausal and median time between primary diagnosis and metastasis was 5.4 years. Most (75.1%) patients received endocrine therapy as first line systemic treatment (1st LoT); use of 1st LoT chemotherapy halved between 2012 and 2017. Patients receiving 1st LoT chemotherapy were younger and more likely to have visceral metastasis (p < 0.01). Median OS was 29.5 months and significantly greater for patients with exclusively non-visceral metastasis (p < 0.01). The adjusted hazard ratio for death of patients with visceral (or CNS) metastasis was 1.91 relative to those with exclusively non-visceral metastasis. CONCLUSIONS: Diverse endocrine therapies predominate as 1st LoT for patients with HR+/HER2- MBC, chemotherapy being associated with more aggressive disease in younger patients, emphasising the importance of using effective and tolerable therapies early.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Inglaterra/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
5.
Heart Lung Circ ; 28(3): e23-e25, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29891247

RESUMO

Myocardial perfusion scanning (MPS) is commonly used to assess patients with an intermediate to high risk of coronary artery disease. Concerns have been raised about the accuracy of this test. There is little recent data regarding the specificity of the MPS in the context of current medical therapy. The primary objective of this study is to determine the specificity of MPS in diagnosing obstructive coronary artery disease. A total of 184 patients fulfilled study criteria. The overall specificity of MPS for obstructive coronary artery disease was 54%.The only demographic variable that influenced specificity was gender: males with a specificity of 66% and females with a specificity of 29% (p-value=0.001). These results suggest that the real world specificity of MPS is lower than previously indicated, particularly in the female population. The limitations proposed by the Cardiac Services Committee Report are therefore unlikely to improve patient outcomes.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Medicare/estatística & dados numéricos , Imagem de Perfusão do Miocárdio/métodos , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/economia , Eletrocardiografia , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Imagem de Perfusão do Miocárdio/economia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Estados Unidos
6.
Eur J Clin Microbiol Infect Dis ; 37(9): 1777-1784, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29959610

RESUMO

Micafungin was reported to be non-inferior to liposomal amphotericin B (LAmB) in treating patients with candidaemia and invasive candidiasis (IC). The current study aimed to evaluate the economic impact of using micafungin versus LAmB for treatment of candidaemia and IC in Turkey. A decision analytic model, which depicted economic consequences upon administration of micafungin or LAmB for treating patients with candidaemia and IC in the Turkish hospitals, was constructed. Patients were switched to an alternative antifungal agent if initial treatment failed due to mycological persistence. All patients were followed up until treatment success or death. Outcome probabilities were obtained from published literature and cost inputs were derived from the latest Turkish resources. Expert panels were used to estimate data that were not available in the literature. Cost per patient treated for each intervention was then calculated. Sensitivity analyses including Monte Carlo simulation were performed. For treatment of candidaemia and IC, micafungin (€4809) was associated with higher total cost than LAmB (€4467), with an additional cost of €341 per treated patient. Cost of initial antifungal treatment was the major cost driver for both comparators. The model outcome was robust over a wide variation in input variables except for drug acquisition cost and duration of initial antifungal treatment with micafungin or LAmB. LAmB is cost-saving relative to micafungin for the treatment of candidaemia and IC from the Turkish hospital perspective, with variation in drug acquisition cost of the critical factor affecting the model outcome.


Assuntos
Anfotericina B/economia , Antifúngicos/economia , Candidemia/tratamento farmacológico , Candidíase Invasiva/tratamento farmacológico , Micafungina/economia , Anfotericina B/administração & dosagem , Anfotericina B/uso terapêutico , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Candidemia/economia , Candidemia/epidemiologia , Candidemia/microbiologia , Candidíase Invasiva/economia , Candidíase Invasiva/epidemiologia , Candidíase Invasiva/microbiologia , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Humanos , Micafungina/administração & dosagem , Micafungina/uso terapêutico , Resultado do Tratamento , Turquia/epidemiologia
7.
BMC Cardiovasc Disord ; 18(1): 80, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29724164

RESUMO

BACKGROUND: Due to a relative lack of outpatient heart failure (HF) clinical registries, we aimed to describe symptoms, signs, and medication treatment among ambulatory patients with heart failure (HF) over time. METHODS: Using health records from 234 PINNACLE (Practice Innovation and Clinical Excellence) U.S. cardiology practices (2008-2014), serial visits for patients with HF were characterized. Symptoms, signs, and HF medications (angiotensin-converting enzyme inhibitors [ACEI], angiotensin receptor blockers [ARB], beta blockers [BB], and diuretics) were compared between visits. RESULTS: Among 763,331 patients with HF, 550,581 had ≥2 clinic visits < 1 year apart, with 2,998,444 visit pairs. In the 12 months following an index visit, patients had a mean of 2.5 ± 2.3 additional visits. Recorded index visit symptoms ranged from dyspnea (53.6%) to orthopnea (23.1%); signs ranged from peripheral edema (52.2%) to hepatomegaly (0.6%). Of those with ejection fraction < 40%, ACEI was prescribed in 58.6%, ARB in 18.5%, BB in 85.2%, and diuretics in 70.0%. Between-visit recorded changes were infrequent: dyspnea appeared in 3.8%, resolved in 2.7%; NYHA class increased in 2.9%, decreased in 2.9%; number of signs increased in 6.0%, decreased in 5.1%; ACEI/ARB or BB added in 6.4%, removed in 6.2%; diuretic added in 3.7%, removed in 3.8%. Changes in recorded symptoms were rarely associated with initiation or discontinuation in HF medication classes. CONCLUSIONS: Ambulatory HF care in U.S. cardiology practices seldom recorded changes in symptoms, signs, and medication class. Although templated medical records and absence of medication dosing likely underestimated the degree to which clinical changes occur over serial visits for HF, these PINNACLE data suggest opportunities for greater symptom-based and therapy-focused visits.


Assuntos
Assistência Ambulatorial , Cardiologia , Fármacos Cardiovasculares/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Fármacos Cardiovasculares/efeitos adversos , Estudos Transversais , Diuréticos/uso terapêutico , Substituição de Medicamentos , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Sistema de Registros , Volume Sistólico/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia , Função Ventricular Esquerda/efeitos dos fármacos
8.
J Am Chem Soc ; 139(2): 819-828, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-27973773

RESUMO

A new hierarchical MOF consisting of Cu(II) centers connected by benzene-tricarboxylates (BTC) is prepared by thermoinduced solid transformation of a dense CuBTC precursor phase. The mechanism of the material formation has been thoroughly elucidated and revealed a transformation of a ribbon-like 1D building unit into 2D layers and finally a 3D network. The new phase contains excess copper, charge compensated by systematic hydroxyl groups, which leads to an open microporous framework with tunable permanent mesoporosity. The new phase is particularly attractive for molecular separation. Energy consumption of adsorptive separation processes can be lowered by using adsorbents that discriminate molecules based on adsorption entropy rather than enthalpy differences. In separation of a 11-component mixture of C1-C6 alkanes, the hierarchical phase outperforms the structurally related microporous HKUST-1 as well as silicate-based hierarchical materials. Grand canonical Monte Carlo (GCMC) simulation provides microscopic insight into the structural host-guest interaction, confirming low adsorption enthalpies and significant entropic contributions to the molecular separation. The unique three-dimensional hierarchical structure as well as the systematic presence of Cu(II) unsaturated coordination sites cause this exceptional behavior.

9.
Am Heart J ; 189: 177-183, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28625374

RESUMO

Heart failure (HF) with reduced ejection fraction (HFrEF) is a common and costly condition that diminishes patients' health status and confers a poor prognosis. Despite the availability of multiple guideline-recommended pharmacologic and cardiac device therapies for patients with chronic HFrEF, outcomes remain suboptimal. Currently, there is limited insight into the rationale underlying clinical decisions by health care providers and patient factors that guide the use and intensity of outpatient HF treatments. A better understanding of current practice patterns has the potential to improve patients' outcomes. The CHAnge the Management of Patients with Heart Failure (CHAMP-HF) registry will evaluate the care and outcomes of patients with chronic HFrEF by assessing real-world treatment patterns, as well as the reasons for and barriers to medication treatment changes. CHAMP-HF will enroll approximately 5,000 patients with chronic HFrEF (left ventricular ejection fraction ≤40%) at approximately 150 US sites, and patients will be followed for a maximum duration of 24 months. Participating sites will collect data from both providers (HF history, examination findings, results of diagnostic studies, pharmacotherapy treatment patterns, decision-making factors, and clinical outcomes) and patients (medication adherence and patient-reported outcomes). The CHAMP-HF registry will provide a unique opportunity to study practice patterns and the adoption of new HF therapies across a diverse mix of health care providers and outpatient practices in the United States that care for HFrEF patients.


Assuntos
Assistência Ambulatorial/métodos , Gerenciamento Clínico , Insuficiência Cardíaca/terapia , Sistema de Registros , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estados Unidos
10.
Chemistry ; 23(15): 3583-3594, 2017 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-27922204

RESUMO

The realization of metal nanoparticles (NPs) with bimetallic character and distinct composition for specific catalytic applications is an intensively studied field. Due to the synergy between metals, most bimetallic particles exhibit unique properties that are hardly provided by the individual monometallic counterparts. However, as small-sized NPs possess high surface energy, agglomeration during catalytic reactions is favored. Sufficient stabilization can be achieved by confinement of NPs in porous support materials. In this sense, metal-organic frameworks (MOFs) in particular have gained a lot of attention during the last years; however, encapsulation of bimetallic species remains challenging. Herein, the exclusive embedding of preformed core-shell PdPt and RuPt NPs into chemically robust Zr-based MOFs is presented. Microstructural characterization manifests partial retention of the core-shell systems after successful encapsulation without harming the crystallinity of the microporous support. The resulting chemically robust NP@UiO-66 materials exhibit enhanced catalytic activity towards the liquid-phase hydrogenation of nitrobenzene, competitive with commercially used Pt on activated carbon, but with superior size-selectivity for sterically varied substrates.

11.
Mycoses ; 60(11): 714-722, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28699297

RESUMO

Anidulafungin has been shown to be non-inferior to, and possibly more efficacious, than fluconazole in treating patients with invasive candidiasis (IC). This study aimed to determine the cost-effectiveness of anidulafungin vs fluconazole for treatment of IC in the Turkish setting. A decision analytic model was constructed to depict downstream economic consequences of using anidulafungin or fluconazole for treatment of IC in the Turkish hospitals. Transition probabilities (ie treatment success, observed or indeterminate treatment failures) were obtained from a published randomised clinical trial. Cost inputs were from the latest Turkish resources. Data not available in the literature were estimated by expert panels. Sensitivity analyses were performed to assess the robustness of the model outcome. While anidulafungin [TL 17 171 (USD 4589)] incurred a higher total cost than fluconazole [TL 8233 (USD 2200) per treated patient, treatment with anidulafungin was estimated to save an additional 0.58 life-years, with an incremental cost-effectiveness ratio of TL 15 410 (USD 4118) per life-years saved. Drug acquisition cost and hospitalisation were the main cost drivers for anidulafungin and fluconazole arms respectively. The model findings were robust over a wide range of input variables except for anidulafungin drug cost. Anidulafungin appears to be a cost-effective therapy in treating IC from the Turkish hospital perspective.


Assuntos
Antifúngicos/uso terapêutico , Candidíase Invasiva/tratamento farmacológico , Equinocandinas/uso terapêutico , Fluconazol/uso terapêutico , Anidulafungina , Antifúngicos/economia , Candidíase Invasiva/microbiologia , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Método Duplo-Cego , Equinocandinas/economia , Fluconazol/economia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Falha de Tratamento , Resultado do Tratamento , Turquia
12.
Nano Lett ; 16(4): 2692-7, 2016 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-26966938

RESUMO

Based on neutron powder diffraction (NPD) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), we show that calcium ions help eliminate the Fe-antisite defects by controlling the nucleation and evolution of the LiFePO4 particles during their hydrothermal synthesis. This Ca-regulated formation of LiFePO4 particles has an overwhelming impact on the removal of their iron antisite defects during the subsequent carbon-coating step since (i) almost all the Fe-antisite defects aggregate at the surface of the LiFePO4 crystal when the crystals are small enough and (ii) the concomitant increase of the surface area, which further exposes the Fe-antisite defects. Our results not only justify a low-cost, efficient and reliable hydrothermal synthesis method for LiFePO4 but also provide a promising alternative viewpoint on the mechanism controlling the nanosizing of LiFePO4, which leads to improved electrochemical performances.


Assuntos
Cálcio/química , Ferro/química , Compostos de Lítio/química , Nanopartículas/química , Fosfatos/química , Nanopartículas/ultraestrutura , Propriedades de Superfície
13.
Chemistry ; 22(10): 3304-3311, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26821605

RESUMO

Metal-organic frameworks (MOFs) feature a great possibility for a broad spectrum of applications. Hollow MOF structures with tunable porosity and multifunctionality at the nanoscale with beneficial properties are desired as hosts for catalytically active species. Herein, we demonstrate the formation of well-defined hollow Zn/Co-based zeolitic imidazolate frameworks (ZIFs) by use of epitaxial growth of Zn-MOF (ZIF-8) on preformed Co-MOF (ZIF-67) nanocrystals that involve in situ self-sacrifice/excavation of the Co-MOF. Moreover, any type of metal nanoparticles can be accommodated in Zn/Co-ZIF shells to generate yolk-shell metal@ZIF structures. Transmission electron microscopy and tomography studies revealed the inclusion of these nanoparticles within hollow Zn/Co-ZIF with dominance of the Zn-MOF as shell. Our findings lead to a generalization of such hollow systems that are working effectively to other types of ZIFs.

14.
Nanotechnology ; 27(42): 425705, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27631569

RESUMO

Ceria nanoparticles (NPs) are fundamental in heterogeneous catalysis because of their ability to store or release oxygen depending on the ambient conditions. Their oxygen storage capacity is strictly related to the exposed planes, crystallinity, density and distribution of defects. In this work a study of ceria NPs produced with a ligand-free, physical synthesis method is presented. The NP films were grown by a magnetron sputtering based gas aggregation source and studied by high resolution- and scanning-transmission electron microscopy and x-ray photoelectron spectroscopy. In particular, the influence of the oxidation procedure on the NP reducibility has been investigated. The different reducibility has been correlated to the exposed planes, crystallinity and density and distribution of structural defects. The results obtained in this work represent a basis to obtain cerium oxide NP with desired oxygen transport properties.

15.
Phys Chem Chem Phys ; 18(4): 3234-43, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26742561

RESUMO

Hydrogen plays an essential role during the in situ assembly of tailored catalytic materials, and serves as key ingredient in multifarious chemical reactions promoted by these catalysts. Despite intensive debate for several decades, the existence and nature of hydrogen-involved mechanisms - such as hydrogen-spillover, surface migration - have not been unambiguously proven and elucidated up to date. Here, Pt-Ga alloy formation is used as a probe reaction to study the behavior and atomic transport of H and Ga, starting from Pt nanoparticles on hydrotalcite-derived Mg(Ga)(Al)Ox supports. In situ XANES spectroscopy, time-resolved TAP kinetic experiments, HAADF-STEM imaging and EDX mapping are combined to probe Pt, Ga and H in a series of H2 reduction experiments up to 650 °C. Mg(Ga)(Al)Ox by itself dissociates hydrogen, but these dissociated hydrogen species do not induce significant reduction of Ga(3+) cations in the support. Only in the presence of Pt, partial reduction of Ga(3+) into Ga(δ+) is observed, suggesting that different reaction mechanisms dominate for Pt- and Mg(Ga)(Al)Ox-dissociated hydrogen species. This partial reduction of Ga(3+) is made possible by Pt-dissociated H species which spillover onto non-reducible Mg(Al)Ox or partially reducible Mg(Ga)(Al)Ox and undergo long-range transport over the support surface. Moderately mobile Ga(δ+)Ox migrates towards Pt clusters, where Ga(δ+) is only fully reduced to Ga(0) on condition of immediate stabilization inside Pt-Ga alloyed nanoparticles.

16.
J Allergy Clin Immunol ; 135(1): 73-80, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25263233

RESUMO

BACKGROUND: It remains unclear whether the quality of acute asthma care in US emergency departments (EDs) has improved over time. OBJECTIVES: We investigated changes in concordance of ED asthma care with 2007 National Institutes of Health guidelines, identified ED characteristics predictive of concordance, and tested whether higher concordance was associated with lower risk of hospitalization. METHODS: We performed chart reviews in ED patients aged 18 to 54 years with asthma exacerbations in 48 EDs during 2 time periods: 1997-2001 (2 prior studies) and 2011-2012 (new study). Concordance with guideline recommendations was evaluated by using item-by-item quality measures and composite concordance scores at the patient and ED levels; these scores ranged from 0 to 100. RESULTS: The analytic cohort comprised 4039 patients (2119 from 1997-2001 vs 1920 from 2011-2012). Over these 16 years, emergency asthma care became more concordant with level A recommendations at both the patient and ED levels (both P < .001). By contrast, concordance with non-level A recommendations (peak expiratory flow measurement and timeliness) decreased at both the patient (median score, 75 [interquartile range, 50-100] to 50 [interquartile range, 33-75], P < .001) and ED (mean score, 67 [SD, 7] to 50 [SD, 16], P < .001) levels. Multivariable analysis demonstrated ED concordance was lower in Southern and Western EDs compared with Midwestern EDs. After adjusting for severity, guideline-concordant care was associated with lower risk of hospitalization (odds ratio, 0.37; 95% CI, 0.26-0.53). CONCLUSIONS: Between 1997 and 2012, we observed changes in the quality of emergency asthma care that differed by level of guideline recommendation and substantial interhospital and geographic variations. Greater concordance with guideline-recommended management might reduce unnecessary hospitalizations.


Assuntos
Asma/terapia , Serviço Hospitalar de Emergência/normas , Tratamento de Emergência/normas , Qualidade da Assistência à Saúde/normas , Adulto , Feminino , Fidelidade a Diretrizes , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estados Unidos
17.
Ann Allergy Asthma Immunol ; 115(4): 306-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26265010

RESUMO

BACKGROUND: Chronic idiopathic (also called spontaneous) urticaria (CIU/CSU) is the most common form of chronic urticaria and has been associated with impairment to health outcomes, although the effect has never been assessed using a nationally representative sample in the United States. OBJECTIVES: To assess the burden of CIU/CSU from the patients' perspective in terms of health related quality of life, impairment to work and nonwork activities, and health care resource use. METHODS: Data were obtained from the US National Health and Wellness Survey. Current use of a prescription for the treatment of chronic hives was used as a proxy for CIU/CSU. Patients with CIU/CSU in the proxy group were matched 1:4 to respondents without chronic hives using survey year, sex, age, and race. Generalized linear models were adjusted for comorbidities, smoking, body mass index, and health insurance status. Outcome measures included the Medical Outcomes Study 12-Item and 36-Item Short Form Health Surveys; self-reported depression, anxiety, and sleep difficulties; the Work Productivity and Activity Impairment questionnaire, and health care resource use. RESULTS: After matching and adjustment for covariates, those currently using a prescription for chronic hives had mental component summary scores 5.7 points lower, physical component summary scores 6.5 points lower, and health utility scores 0.11 points lower than controls, as well as higher adjusted odds of reporting depression, anxiety, and sleep difficulties. Mean adjusted work impairment was approximately double in prescription-treated chronic hives relative to controls, as was frequency of health care visits. CONCLUSION: Chronic hives substantially affects quality of life, nonwork activities, capacity to work, and health care use, providing further evidence of a high burden of CIU/CSU across multiple health outcomes and unmet need for effective treatment.


Assuntos
Urticária/epidemiologia , Urticária/psicologia , Ansiedade/psicologia , Índice de Massa Corporal , Doença Crônica , Comorbidade , Efeitos Psicossociais da Doença , Estudos Transversais , Depressão/psicologia , Feminino , Inquéritos Epidemiológicos , Humanos , Seguro Saúde/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Estudos Retrospectivos , Fumar/epidemiologia , Inquéritos e Questionários , Resultado do Tratamento , Estados Unidos , Urticária/tratamento farmacológico
18.
COPD ; 12(5): 473-83, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26244570

RESUMO

A retrospective analysis of a cross-sectional, multicenter survey was conducted in United States (US) medical practices to evaluate the concordance between patients with COPD and their physicians on disease-specific characteristics. Associations between patient and disease-related characteristics with monotherapy, dual therapy, or triple therapy prescribed as COPD maintenance regimens were also examined. Eligible physicians completed patient record forms (PRFs) for up to 6 consecutive patients with COPD. Patients for whom a PRF was completed were invited to complete a patient self-completion (PSC) survey consisting of questions similar to those on the PRF, as well as several validated measures to assess the impact of COPD on patients' lives. A total of 469 patients completed a PSC that was matched with the PRF completed by their physician, forming the sample for the concordance analysis. Moderate agreement (kappa (κ) = 0.41-0.60) was observed for 79% of measures, with the lowest concordance rating corresponding to hemoptysis (κ = 0.22). There were few differences in demographic or clinical characteristics between patients prescribed monotherapy and dual therapy. Triple therapy rather than monotherapy or dual therapy was more often prescribed for patients with greater frequency of symptoms, negative impact of COPD on daily life and interpersonal relationships, and respiratory impairment based on the most recent FEV1. Diverse factors influence US physicians' perceptions of disease and treatment choices, including patient symptoms, quality of life, and disease impact. Our results highlight that concordance between physicians and patients regarding symptoms and physical function may contribute to optimal management of COPD.


Assuntos
Satisfação do Paciente/estatística & dados numéricos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Avaliação de Sintomas , Idoso , Estudos Transversais , Quimioterapia Combinada , Dispneia/etiologia , Feminino , Volume Expiratório Forçado , Hemoptise/etiologia , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Qualidade de Vida , Sons Respiratórios/etiologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Inquéritos e Questionários
19.
Nano Lett ; 14(8): 4342-51, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-24971997

RESUMO

Controlling the morphology of nanowires in bottom-up synthesis and assembling them on planar substrates is of tremendous importance for device applications in electronics, photonics, sensing and energy conversion. To date, however, there remain challenges in reliably achieving these goals of orientation-controlled nanowire synthesis and assembly. Here we report that growth of planar, vertical and randomly oriented tin-doped indium oxide (ITO) nanowires can be realized on yttria-stabilized zirconia (YSZ) substrates via the epitaxy-assisted vapor-liquid-solid (VLS) mechanism, by simply regulating the growth conditions, in particular the growth temperature. This robust control on nanowire orientation is facilitated by the small lattice mismatch of 1.6% between ITO and YSZ. Further control of the orientation, symmetry and shape of the nanowires can be achieved by using YSZ substrates with (110) and (111), in addition to (100) surfaces. Based on these insights, we succeed in growing regular arrays of planar ITO nanowires from patterned catalyst nanoparticles. Overall, our discovery of unprecedented orientation control in ITO nanowires advances the general VLS synthesis, providing a robust epitaxy-based approach toward rational synthesis of nanowires.

20.
Small ; 10(6): 1106-15, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24500945

RESUMO

High pressure high temperature (HPHT) nanodiamonds (NDs) represent extremely promising materials for construction of fluorescent nanoprobes and nanosensors. However, some properties of bare NDs limit their direct use in these applications: they precipitate in biological solutions, only a limited set of bio-orthogonal conjugation techniques is available and the accessible material is greatly polydisperse in shape. In this work, we encapsulate bright 30-nm fluorescent nanodiamonds (FNDs) in 10-20-nm thick translucent (i.e., not altering FND fluorescence) silica shells, yielding monodisperse near-spherical particles of mean diameter 66 nm. High yield modification of the shells with PEG chains stabilizes the particles in ionic solutions, making them applicable in biological environments. We further modify the opposite ends of PEG chains with fluorescent dyes or vectoring peptide using click chemistry. High conversion of this bio-orthogonal coupling yielded circa 2000 dye or peptide molecules on a single FND. We demonstrate the superior properties of these particles by in vitro interaction with human prostate cancer cells: while bare nanodiamonds strongly aggregate in the buffer and adsorb onto the cell membrane, the shell encapsulated NDs do not adsorb nonspecifically and they penetrate inside the cells.


Assuntos
Materiais Biocompatíveis/química , Corantes Fluorescentes/química , Nanodiamantes/química , Linhagem Celular Tumoral , Elétrons , Humanos , Luminescência , Microscopia Confocal , Nanodiamantes/ultraestrutura , Polietilenoglicóis/química , Dióxido de Silício/química , Espectrofotometria Infravermelho
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