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This review focuses on the green synthesis methods, challenges, and applications of manganese oxide (Mn3O4) nanoparticles investigated in the past five years. Mn3O4nanoparticles offer some unique properties that are attributed in part to the presence of mixed oxidation states of manganese (i.e. +2 and +3) in the particle, which can be utilized in a wide range of redox-sensitive applications, such as in developing supercapacitive energy storage materials. In addition, the green synthesis of Mn3O4nanoparticles through plant extracts has potential uses in sustainable nanotechnology. Various plant extract-mediated synthesis techniques for Mn3O4nanoparticles have been investigated and presented. By comparing the size and structure of the synthesized Mn3O4nanoparticles, we have observed a consistent pattern of obtaining spherical particles with a size ranging from 16 to 50 nm. The morphology of the generated Mn3O4nanoparticles can be influenced by the annealing temperature and the composition of the plant extract used during the nanoparticle synthesis. Additionally, numerous applications for the greenly produced Mn3O4nanoparticles have been demonstrated. Mn3O4nanoparticles derived from plant extracts have been found to possess antimicrobial properties, supercapacitive and electrochemical capabilities, and excellent pollutant degradation efficiency. However, the magnetic properties of these nanoparticles synthesized by plant extracts are yet to be explored for potential biomedical applications. Finally, challenges to existing synthetic methods and future perspectives on the potential applications of these green synthesized Mn3O4nanoparticles are highlighted.
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Light-activated sensors are of great interest for biological applications but are limited by the depth of penetration of light. We have been interested in transducing light activation to a magnetic signal that can be detected through noninvasive imaging by magnetic resonance imaging (MRI). We have previously developed agents incorporating spiropyran derivatives as the sensing moiety and characterized features that influence photoswitching; however, we found the MRI response to be unpredictable. In this work, we delve deeper into the potential mechanisms for the observed MRI responses in an effort to better understand the structural effects on controlling magnetic properties. A series of light-activatable MRI contrast agents were synthesized and characterized to assess the effect of spiropyran positioning on contrast agent functions and properties. These compounds are based on the same spiropyran skeleton, also named 1',3',3'-trimethyl-6-nitrospiro[chromene-2,2-indoline], which is linked with an MRI contrast agent, gadolinium-1,4,7,10-tetraazacyclododecane-1,4,7-triacetate (DO3A). We investigated the photo-to-magnetic conversion properties of these novel compounds by adjusting linker lengths over a range from three to seven methylene groups. The primary results indicated that the contrast agent with a five-carbon linker (25) showed the highest light-sensing ability after irradiation with visible light. The results will aid in the design of future spiropyran-based MRI sensors.
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Meios de Contraste , Gadolínio , Imageamento por Ressonância MagnéticaRESUMO
Mesostructured pillared zeolite materials in the form of lamellar phases with a crystal structure of mordenite (MOR) and ZSM-5 (MFI) were grown using CTAB as an agent that creates mesopores, in a one-pot synthesis; then into the CTAB layers separating the 2D zeolite plates were introduced by diffusion the TEOS molecules which were further hydrolyzed, and finally the material was annealed to remove the organic phase, leaving the 2D zeolite plates separated by pillars of silicon dioxide. To monitor the successive structural changes and the state of the atoms of the zeolite framework and organic compounds at all the steps of the synthesis of pillared MOR and MFI zeolites, the nuclear magnetic resonance method (NMR) with magic angle spinning (MAS) was applied. The 27Al and 29Si MAS NMR spectra confirm the regularity of the zeolite frameworks of the as synthetized materials. Analysis of the 1H and 13C MAS NMR spectra and an experiment with variable contact time evidence a strong interaction between the charged "heads" -[N(CH3)3]+ of CTAB and the zeolite framework at the place of [AlO4]- location. According to 27Al and 29Si MAS NMR the evacuation of organic cations leads to a partial but not critical collapse of the local zeolite structure.
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Silicatos de Alumínio/química , Ressonância Magnética Nuclear Biomolecular/métodos , Zeolitas/química , Alumínio , Varredura Diferencial de Calorimetria , Cetrimônio/química , Cristalização , Isótopos , Microscopia Eletrônica de Varredura , Silício , Espectrometria por Raios X , Termogravimetria , Difração de Raios XRESUMO
Recent advances in high-throughput sequencing technology have led to a rapid expansion in the number of viral sequences associated with samples from vertebrates, invertebrates and environmental samples. Accurate host identification can be difficult in assays of complex samples that contain more than one potential host. Using unbiased metagenomic sequencing, we investigated wild house mice (Mus musculus) and brown rats (Rattus norvegicus) from New York City to determine the aetiology of liver disease. Light microscopy was used to characterize liver disease, and fluorescent microscopy with in situ hybridization was employed to identify viral cell tropism. Sequences representing two novel negative-sense RNA viruses were identified in homogenates of wild house mouse liver tissue: Amsterdam virus and Fulton virus. In situ hybridization localized viral RNA to Capillaria hepatica, a parasitic nematode that had infected the mouse liver. RNA from either virus was found within nematode adults and unembryonated eggs. Expanded PCR screening identified brown rats as a second rodent host for C. hepatica as well as both nematode-associated viruses. Our findings indicate that the current diversity of nematode-associated viruses may be underappreciated and that anatomical imaging offers an alternative to computational host assignment approaches.
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Animais Selvagens/parasitologia , Capillaria/virologia , Infecções por Enoplida/veterinária , Vírus de RNA/isolamento & purificação , Doenças dos Roedores/parasitologia , Animais , Capillaria/fisiologia , Infecções por Enoplida/parasitologia , Evolução Molecular , Fígado/parasitologia , Camundongos , Cidade de Nova Iorque , Filogenia , Vírus de RNA/classificação , Vírus de RNA/genética , RatosRESUMO
Mexico is the world's largest producer, exporter, and consumer of avocados. "Hass" avocado is the most commercialized cultivar, while the native Mexican avocado varieties have been displaced. Thus, studies regarding their chemical and nutraceutical characterization are scarce. We studied the total lipid content, fatty acid profile, carotenoid content, and free radical-scavenging activity of the fruit pulp from 12 accessions of the native Mexican avocado (Persea americana var. drymifolia). The results show that the chemical and nutraceutical characteristics depend on the accession type. The total lipid content ranged from 13.22 to 23.41%. The major saturated fatty acid in all the avocado accessions was palmitic acid (15.54-22.68%). Monounsaturated fatty acids, like oleic (56.58-74.19%), linoleic (5.62-16.85%) and linolenic (0.63-2.85%) acids were the most abundant unsaturated fatty acids in all the native Mexican avocado accessions. The total carotenoid content (1.57 to 7.83 mg eq. of ß-carotene 100 g-1 fresh weight) and the free radical-scavenging activity (7.58-88.62 mMol trolox equivalent 100 g-1 fresh weight) also varied significantly (p < 0.05) among accessions. Native Mexican avocados have a great nutraceutical potential due to their high content of omega-9, omega-6, and omega-3 fatty acids and carotenoids. These compounds have been reported to display antioxidant activities and protect against cardiovascular diseases.
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Persea , Carotenoides , Ácidos Graxos , Radicais Livres , MéxicoRESUMO
Mexican landrace avocados are naturally distributed mainly in high areas of central Mexico, where they have been produced and consumed since pre-Hispanic times. However, trees of these species are being replaced by improved varieties with greater global demand, and many species have been lost due to the destruction of their natural habitats. Many people in Mexico like to consume the pulp and peel of these fruits and have done so since pre-Hispanic times. This is because the peel of Mexican landrace avocados, unlike the peel of Hass avocados, is very thin and flavorful. The peel color may be bluish-purple or dark reddish due to the presence of anthocyanins, which are compounds with antioxidant activity. The objective of this study was to assess the oil and anthocyanin contents and to evaluate the antioxidant activity in fruits of 11 accessions collected from producing-regions of Mexico. The oil content was 16.2 to 32.3 g 100 g-1 in pulp, and the main unsaturated fatty acids were oleic, linoleic and palmitoleic acids, depending on the accession. The anthocyanin contents in peels ranged from 0.64 to 47 mg g-1 fresh weight. The highest antioxidant activity was found in the peel (53.3-307.3 mmol g-1 fresh weight). The results confirm that the pulp and peel of dark-peel Mexican landrace avocados could be important nutraceuticals for humans.
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Antocianinas/análise , Antioxidantes/análise , Suplementos Nutricionais/análise , Ácidos Graxos/análise , Persea/química , Óleos de Plantas/análise , Frutas/química , Humanos , México , Especificidade da EspécieRESUMO
Due to its impact on human health and its capacity to cause damage, disasters are one of the global problems that most concern the international community. However, and in spite of the efforts made by many health systems, the reduction of vulnerabilities and the lack of strategies to avoid or minimize risks have not received enough attention yet. As Cuba is located in an area of permanent danger of disasters, its health sector has accumulated considerable experience in the management of risks and in the assurance of less risky future scenarios, with active participation of the community and a planned and organized process to address the impact of climate change. This paper summarizes some of these experiences and describes the dangers, vulnerabilities, and risks of disasters in Cuba, its Civil Defense System, and planning and organization in the health sector for disaster reduction, as well as the main effects and challenges of climate change in the health system. Lessons learned and good practices support the key role of human resources to reduce vulnerabilities; the greatest challenges are to avoid or minimize risks, to advance research, to train professionals for climate change, and to optimize the organization of health systems and services in the country.
Devido ao seu impacto na saúde humana e na sua capacidade de causar danos, os desastres são um dos problemas globais mais preocupantes para a comunidade internacional. No entanto, e apesar dos esforços feitos por numerosos sistemas de saúde, a atenção necessária ainda não foi oferecida para a redução de vulnerabilidades e a falta de estratégias que evitem ou minimizem os riscos. Como Cuba está localizada em uma área de permanente perigo de desastres, seu setor de saúde acumulou uma experiência considerável no gerenciamento de riscos e na garantia de cenários futuros menos arriscados, com a participação ativa da comunidade e um processo planejado e organizado para enfrentar o impacto das mudanças climáticas. Este artigo resume algumas dessas experiências e descreve os perigos, vulnerabilidades e riscos de desastres em Cuba, seu Sistema de Defesa Civil e planejamento e organização no setor da saúde para a redução de desastres, bem como os principais efeitos e desafios das mudanças climáticas no sistema de saúde. As lições aprendidas e as boas práticas ratificam o papel determinante dos recursos humanos para reduzir vulnerabilidades; o maior desafio é evitar ou minimizar riscos, avançar pesquisa, preparar profissionais para mudanças climáticas e otimizar a organização de sistemas e serviços de saúde no país.
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No discussion of challenges for chemistry in molecular imaging would be complete without addressing the elephant in the room-which is that the purest of chemical compounds needs to interact with a biological system in a manner that does not perturb normal biology while still providing efficacious feedback to assist in diagnosis of disease. In the past decade, magnetic resonance imaging (MRI) agents long considered inert have produced adverse effects in certain patient populations under certain treatment regimens. More recently, inert blood pool agents have been found to deposit in the brain. Release of free metal is often suspected as the culprit but that hypothesis has yet to be validated. In addition, even innocuous agents can cause painful side effects during injection in some patients. In this brief review, we summarize known biological effects for gadolinium- and iron-based MRI contrast agents, and discuss some of the potential mechanisms for the observed biological effects, including the potential role of phosphorus imbalance, related to kidney disease or cancer, in destabilizing gadolinium-based chelates and precipitating free gadolinium.This article is part of the themed issue 'Challenges for chemistry in molecular imaging'.
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Meios de Contraste/efeitos adversos , Gadolínio/efeitos adversos , Imageamento por Ressonância Magnética/efeitos adversos , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Meios de Contraste/química , Meios de Contraste/farmacocinética , Gadolínio/química , Gadolínio/farmacocinética , Humanos , Modelos Biológicos , Imagem Molecular/efeitos adversos , Dermopatia Fibrosante Nefrogênica/etiologia , Fósforo/metabolismo , Insuficiência Renal/diagnóstico por imagem , Insuficiência Renal/metabolismoRESUMO
In this work we synthesize molecular switches that are responsive to cysteine, homocysteine, and glutathione; three redox systems that make up the majority of the body's antioxidant defenses. Synthesized spiropyran isomers with conjugation-ready linkages showed good selectivity of response to these major antioxidant thiols over nucleophilic amino acids; however the position of the linking group can affect selectivity and reversibility of the switching response. An isomer with selectivity for cysteine against GSH and Hcy was identified.
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Introduction Pulmonary embolism (PE) is associated with approximately 10.5% of maternal deaths in the United States. Despite heightened awareness of its mortality potential, there islittle data available to guide its management in pregnancy. We present the case of a massive PE during gestation successfully treated with catheter-directed embolectomy. Case Presentation A 37-year-old G2P1001 presented with a syncopal episode preceded by dyspnea and chest pain. Upon presentation, she was hypotensive, tachycardiac, and hypoxic. Imaging showed an occlusive bilateral PE, right heart strain, and a possible intrauterine pregnancy. Beta-human chorionic gonadotropin was positive. She was taken emergently for catheter-directed embolectomy. Her condition immediately improved afterward. Postprocedure pelvic ultrasound confirmed a viable intrauterine pregnancy at 10 weeks gestation. She was discharged with therapeutic enoxaparin and gave birth to a healthy infant at 38 weeks gestation. Conclusion Despite being the gold standard for PE treatment in nonpregnant adults, systemic thrombolysis is relatively contraindicated in pregnancy due to concern for maternal or fetal hemorrhage. Surgical or catheter-based thrombectomies are rarely recommended. Limited alternative options force their consideration, particularly in a hemodynamically unstable patient. Catheter-directed embolectomy can possibly bypass such complications. Our case exemplifies the consideration of catheter-directed embolectomy as the initial treatment modality of a hemodynamically unstable gestational PE.
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BACKGROUND Histoplasma capsulatum is prevalent in the mid-eastern United States and is an environmental fungus that causes human infection by the inhalation of its spores. It is commonly associated with areas containing large amounts of bird excrement and can survive for years in the soil. Only 1% of infected individuals develop disseminated histoplasmosis or Histoplasma endocarditis. CASE REPORT A 61-year-old man with atrial fibrillation had 8 months of fatigue, low-grade fevers, night sweats, and unexplained weight loss presented to the Emergency Department. He worked and lived in Central Florida and although he raised cattle, he denied exposure to birds or bats with regularity. A transesophageal echocardiogram confirmed a sessile echo density on the atrial surface of the mitral valve. His microbial Karius cell-free DNA test from his blood sample was positive for Histoplasma capsulatum, and he was immediately given intravenous liposomal amphotericin for 2 weeks. A tissue valve was used to successfully replace his mitral valve along with a coronary artery bypass and a maze procedure for his persistent atrial fibrillation and atrial flutter. The diagnosis of mitral valve endocarditis from disseminated histoplasmosis was confirmed by pathological analysis, and he was sent home on long-term itraconazole maintenance treatment. CONCLUSIONS Surgical intervention in combination with anti-fungal medication can be a lifesaving intervention for disseminated histoplasmosis. A thorough history is particularly important when evaluating a patient with an unknown infectious source, especially assessing for risk factors, including exposure to environmental factors, workplace, and animals.
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Endocardite , Histoplasmose , Valva Mitral , Humanos , Histoplasmose/diagnóstico , Masculino , Pessoa de Meia-Idade , Endocardite/microbiologia , Endocardite/diagnóstico , Florida , Antifúngicos/uso terapêutico , Ecocardiografia Transesofagiana , Doenças das Valvas Cardíacas/microbiologia , Histoplasma/isolamento & purificaçãoRESUMO
Vector-borne diseases are a major source of morbidity in Panama. Herein, we describe historical usage patterns of synthetic insecticides to control arthropod disease vectors in this country. We examine the influence of interventions by vector control programs on the emergence of insecticide resistance. Chemical control has traditionally focused on two mosquito species: Anopheles albimanus, a major regional malaria vector, and Aedes aegypti, a historical vector of yellow fever, and current vector of dengue, chikungunya, and Zika. Countrywide populations of An. albimanus depict hyperirritability to organochlorine insecticides administered by indoor residual spraying, although they appear susceptible to these insecticides in bioassays settings, as well as to organophosphate and carbamate insecticides in field tests. Populations of Ae. aegypti show resistance to pyrethroids, particularly in areas near Panama City, but the spread of resistance remains unknown in Ae. aegypti and Aedes albopictus. A One Health approach is needed in Panama to pinpoint the insecticide resistance mechanisms including the frequency of knockdown mutations and behavioral plasticity in populations of Anopheles and Aedes mosquitoes. This information is necessary to guide the sustainable implementation of chemical control strategies and the use of modern vector control technologies such as genetically modified mosquitoes, and endosymbiont Wolbachia-based biological control.
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Inseticidas , Controle de Mosquitos , Mosquitos Vetores , Doenças Transmitidas por Vetores , Animais , Humanos , Aedes/efeitos dos fármacos , Anopheles/efeitos dos fármacos , História do Século XX , História do Século XXI , Resistência a Inseticidas , Inseticidas/farmacologia , Controle de Mosquitos/métodos , Mosquitos Vetores/efeitos dos fármacos , Panamá , Doenças Transmitidas por Vetores/prevenção & controleRESUMO
BACKGROUND: The Department of Veterans Affairs Randomized On/Off Bypass (ROOBY) trial compared clinical and angiographic outcomes in off-pump versus on-pump coronary artery bypass graft (CABG) surgery to ascertain the relative efficacy of the 2 techniques. METHODS AND RESULTS: From February 2002 to May 2007, the ROOBY trial randomized 2203 patients to off-pump versus on-pump CABG. Follow-up angiography was obtained in 685 off-pump (62%) and 685 on-pump (62%) patients. Angiograms were analyzed (blinded to treatment) for FitzGibbon classification (A=widely patent, B=flow limited, O=occluded) and effective revascularization. Effective revascularization was defined as follows: All 3 major coronary territories with significant disease were revascularized by a FitzGibbon A-quality graft to the major diseased artery, and there were no new postanastomotic lesions. Off-pump CABG resulted in lower FitzGibbon A patency rates than on-pump CABG for arterial conduits (85.8% versus 91.4%; P=0.003) and saphenous vein grafts (72.7% versus 80.4%; P<0.001). Fewer off-pump patients were effectively revascularized (50.1% versus 63.9% on-pump; P<0.001). Within each major coronary territory, effective revascularization was worse off pump than on pump (all P≤0.001). The 1-year adverse cardiac event rate was 16.4% in patients with ineffective revascularization versus 5.9% in patients with effective revascularization (P<0.001). CONCLUSIONS: Off-pump CABG resulted in significantly lower FitzGibbon A patency for arterial and saphenous vein graft conduits and less effective revascularization than on-pump CABG. At 1 year, patients with less effective revascularization had higher adverse event rates. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00032630.
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Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Ponte de Artéria Coronária sem Circulação Extracorpórea/métodos , Doença das Coronárias/cirurgia , Oclusão de Enxerto Vascular/etiologia , Revascularização Miocárdica , Idoso , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Seguimentos , Oclusão de Enxerto Vascular/diagnóstico por imagem , Sobrevivência de Enxerto/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Radial/fisiologia , Artéria Radial/transplante , Veia Safena/fisiologia , Veia Safena/transplante , Grau de Desobstrução Vascular/fisiologia , VeteranosRESUMO
The formation and properties of silver and iron nanoscale components in the Ag-Fe bimetallic system deposited on mordenite depend on several parameters during their preparation. Previously, it was shown that an important condition for optimizing nano-center properties in a bimetallic catalyst is to change the order of sequential deposition of components; the order "first Ag+, then Fe2+" was chosen as optimal. In this work, the influence of exact Ag/Fe atomic proportion on the system's physicochemical properties was studied. This ratio has been confirmed to affect the stoichiometry of the reduction-oxidation processes involving Ag+ and Fe2+, as shown by XRD, DR UV-Vis, XPS, and XAFS data, while HRTEM, SBET and TPD-NH3 show little change. However, it was found the correlation between the occurrence and amount of the Fe3+ ions incorporated into the zeolite's framework and the experimentally determined catalytic activities towards the model de-NOx reaction along the series of nanomaterials elucidated in this present paper.
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Hydroxytyrosol (HT) is a bioactive phenolic compound naturally present in olives and extra virgin olive oil (EVOO) which is described as an antioxidant, antitumoral and antiangiogenic molecule. Previous studies of semi-synthetic HT-derivatives presented the hydroxytyrosyl alkyl ether HT-C6 as one of the most potent derivatives studied in the context of antioxidant, anti-platelet and antiangiogenic assays, but its direct effect on inflammation was not reported. In this work, we use RT-qPCR measure of gene expression, protein analysis by Western-blot and immunofluorescence techniques, adhesion and migration functional assays and single-cell monitoring of reactive oxygen species (ROS) in order to explore in vitro the ability of HT-C6 to interfere in the inflammatory response of endothelial cells (ECs). Our results showed that HT-C6 strongly reduces the TNF-α-induced expression of vascular cell adhesion molecule 1 (VCAM1), intercellular cell adhesion molecule 1 (ICAM1), E-selectin (SELE), C-C motif chemokine ligand 2 and 5 (CCL2 and CCL5) in HUVECs, impairing the chemotactic and adhesion potential of these cells towards THP-1 monocytes in vitro. In this work, we define a mechanism of action underlying the anti-inflammatory effect of HT-C6, which involves the abrogation of nuclear factor kappa B (NF-κB) pathway activation in ECs. These results, together with the ability of HT-C6 to reduce ROS formation in ECs, point to this compound as a promising HT-derivative to be tested in the treatment of atherosclerosis.
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Spain dominates avocado production in Europe, with the Hass variety being the most prominent. Despite this, Spanish production satisfies less than 10% of the overall avocado demand in Europe. Consequently, the European avocado market heavily relies on imports from overseas, primarily sourced from Peru and Chile. Herein, a comprehensive characterization of the metabolic profile of Hass avocado fruits from Spain, Peru, and Chile, available in the European market throughout the year, was carried out. The determination of relevant substances was performed using high- and low-resolution RP-LC-MS. Remarkable quantitative differences regarding phenolic compounds, amino acids, and nucleosides were observed. Principal component analysis revealed a natural clustering of avocados according to geographical origin. Moreover, a specific metabolic pattern was established for each avocado-producing country using supervised partial least squares discriminant analysis. Spanish fruits exhibited high levels of coumaric acid malonyl-hexose II, coumaric acid hexose II, and ferulic acid hexose II, together with considerably low levels of pantothenic acid and uridine. Chilean avocado fruits presented high concentrations of abscisic acid, uridine, ferulic acid, succinic acid, and tryptophan. Fruits from Peru showed high concentrations of dihydroxybenzoic acid hexose, alongside very low levels of p-coumaric acid, ferulic acid, coumaric acid malonyl-hexose I, and ferulic acid hexose II.
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OBJECTIVES: We sought to evaluate the clinical outcomes of a consecutive series of patients treated for iliac artery occlusive disease (IAOD) using contemporary endovascular technology and techniques. BACKGROUND: As an increasingly complex spectrum of IAOD is treated using endovascular revascularization, there is a need to examine the rates of acute procedural success, complications, and patency to validate the role of an endovascular-first approach to revascularization in contemporary practice. METHODS: All patients with IAOD who were treated using endovascular therapy between September 2005 and September 2010 were identified from a prospectively collected database. Baseline patient characteristics, anatomic details, procedural data, and clinical outcomes were assessed retrospectively. Patency and mortality rates were estimated with the Kaplan-Meier method. RESULTS: A total 59 patients underwent 62 procedures. Trans-Atlantic Inter-Society Consensus (TASC) II types B, C, and D disease accounted for 59%, 7%, and 37% of patients, respectively. The procedure was technically successful in 60 of 62 cases (97%) with no procedure-related mortality. Major complications occurred in five procedures (8%). The mean (±standard deviation) duration of follow-up was 2.3 ± 1.4 years. In patients with a successful revascularization, primary and secondary patency rates were 86% and 94% at 1 year, and 77% and 91% at 2 years, respectively. The TASC II classification of disease did not predict the rate of acute technical success or medium-term patency rates. CONCLUSIONS: The acute and medium-term clinical outcomes of this series of patients with anatomically complex IAOD support the current paradigm of an endovascular-first approach to revascularization.
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Arteriopatias Oclusivas/terapia , Procedimentos Endovasculares , Artéria Ilíaca , Idoso , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/mortalidade , Arteriopatias Oclusivas/fisiopatologia , Constrição Patológica , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/fisiopatologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Stents , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
Recent advances in the coordination chemistry of Eu(2+) are reviewed. Common synthetic routes for generating discrete Eu(2+)-containing complexes reported since 2000 are summarized, followed by a description of the reactivity of these complexes and their applications in reduction chemistry, polymerization, luminescence, and as contrast agents for magnetic resonance imaging. Rapid development of the coordination chemistry of Eu(2+) has led to an upsurge in the utilization of Eu(2+)-containing complexes in synthetic chemistry, materials science, and medicine.
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The kinetic stabilities and relaxivities of a series of Eu(2+)-containing cryptates have been investigated. Transmetallation studies that monitored the change in the longitudinal relaxation rate of water protons in the presence of Ca(2+), Mg(2+), and Zn(2+) demonstrated that cryptate structure influences stability, and two of the cryptates studied were inert to transmetallation in the presence of these endogenous ions. The efficacy of these cryptates was determined at different magnetic field strengths, temperatures, and pH values. Cryptate relaxivity was found to be higher at ultra-high field strengths (7 and 9.4 T) relative to clinically relevant field strengths (1.4 and 3 T), but the efficiency of these cryptates decreased as temperature increased. In addition, variation in pH did not yield significant changes in the efficacy of the cryptates. These studies establish a foundation of important properties that are necessary to develop effective positive contrast agents for magnetic resonance imaging from Eu(2+)-containing cryptates.