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1.
Cell ; 166(4): 907-919, 2016 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-27499021

RESUMEN

Classically, G protein-coupled receptor (GPCR) stimulation promotes G protein signaling at the plasma membrane, followed by rapid ß-arrestin-mediated desensitization and receptor internalization into endosomes. However, it has been demonstrated that some GPCRs activate G proteins from within internalized cellular compartments, resulting in sustained signaling. We have used a variety of biochemical, biophysical, and cell-based methods to demonstrate the existence, functionality, and architecture of internalized receptor complexes composed of a single GPCR, ß-arrestin, and G protein. These super-complexes or "megaplexes" more readily form at receptors that interact strongly with ß-arrestins via a C-terminal tail containing clusters of serine/threonine phosphorylation sites. Single-particle electron microscopy analysis of negative-stained purified megaplexes reveals that a single receptor simultaneously binds through its core region with G protein and through its phosphorylated C-terminal tail with ß-arrestin. The formation of such megaplexes provides a potential physical basis for the newly appreciated sustained G protein signaling from internalized GPCRs.


Asunto(s)
Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , beta-Arrestinas/metabolismo , Transferencia de Energía por Resonancia de Bioluminiscencia , AMP Cíclico/metabolismo , Endosomas/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Células HEK293 , Humanos , Microscopía Confocal , Microscopía Electrónica , Complejos Multiproteicos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/química , beta-Arrestinas/química
2.
Development ; 148(3)2021 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-33462113

RESUMEN

Macrophages are components of the innate immune system with key roles in tissue inflammation and repair. It is now evident that macrophages also support organogenesis, but few studies have characterized their identity, ontogeny and function during heart development. Here, we show that the distribution and prevalence of resident macrophages in the subepicardial compartment of the developing heart coincides with the emergence of new lymphatics, and that macrophages interact closely with the nascent lymphatic capillaries. Consequently, global macrophage deficiency led to extensive vessel disruption, with mutant hearts exhibiting shortened and mis-patterned lymphatics. The origin of cardiac macrophages was linked to the yolk sac and foetal liver. Moreover, the Cx3cr1+ myeloid lineage was found to play essential functions in the remodelling of the lymphatic endothelium. Mechanistically, macrophage hyaluronan was required for lymphatic sprouting by mediating direct macrophage-lymphatic endothelial cell interactions. Together, these findings reveal insight into the role of macrophages as indispensable mediators of lymphatic growth during the development of the mammalian cardiac vasculature.


Asunto(s)
Corazón/crecimiento & desarrollo , Vasos Linfáticos , Macrófagos/metabolismo , Animales , Receptor 1 de Quimiocinas CX3C/genética , Adhesión Celular , Línea Celular , Células Endoteliales , Regulación del Desarrollo de la Expresión Génica , Técnicas de Sustitución del Gen , Humanos , Inflamación , Linfangiogénesis , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Organogénesis/genética , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Saco Vitelino
3.
Catheter Cardiovasc Interv ; 102(2): 328-338, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37393603

RESUMEN

BACKGROUND: Valve-in-valve (VIV) transcatheter aortic valve implantation (TAVI) is a less invasive therapeutic option compared with redo surgical valve replacement for high-risk patients. Relative to procedures within stented surgical valves, VIV-TAVI within stentless valves is associated with a higher complication rate due to challenging underlying anatomy and absence of fluoroscopic landmarks. AIMS: We share a single-center experience with VIV-TAVI in stentless valves, discussing our procedural insights and associated outcomes. METHODS: Our institutional database was queried, and 25 patients who had undergone VIV-TAVI within a stentless bioprosthesis, homograft, or valve-sparing aortic root replacement between 2013 and 2022 were found. Outcome endpoints were based on the Valve Academic Research Consortium-3 criteria. RESULTS: The mean age of the cohort was 69.5 ± 13.6 years. VIV implantation was performed within a homograft in 11 patients, a stentless bioprothesis in 10 patients, and a valve-sparing aortic root replacement in 4 patients. Nineteen (76%) balloon-expandable valves, 5 (20%) self-expanding valves, and one mechanically-expandable (4%) valve were implanted with 100% procedural success, with no instances of significant paravalvular leak, coronary occlusion, or device embolization. There was one (4%) in-hospitality mortality after an emergency procedure; one (4%) patient experienced a transient ischemic attack; and two (8%) patients required permanent pacemaker implantation. The median length of hospital stay was 2 days. After a median follow-up time of 16.5 months, valve function was acceptable in all patients with available data. CONCLUSION: VIV-TAVI within stentless valves can be safely performed with methodical procedural technique and can provide clinical benefit in patients at high reoperation risk.


Asunto(s)
Estenosis de la Válvula Aórtica , Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Resultado del Tratamiento , Diseño de Prótesis , Estenosis de la Válvula Aórtica/cirugía
4.
Oral Dis ; 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36750413

RESUMEN

To evaluate the timing, duration and incidence of bacteremia following invasive dental procedures (IDPs) or activities of daily living (ADL). Eight databases were searched for randomized (RCTs) and nonrandomized controlled trials (nRCTs) evaluating bacteremia before and after IDPs or ADL in healthy individuals. The risk of bias was assessed by RoB 2.0 and ROBINS-I. For the meta-analysis, the primary outcomes were the timing and duration of bacteremia. The secondary outcome was the incidence of bacteremia, measuring the proportion of patients with bacteremia within 5 min after the end of the procedure compared with baseline. We included 64 nRCTs and 25 RCTs. Peak bacteremia occurred within 5 min after the procedure and then decreased over time. Dental extractions showed the highest incidence of bacteremia (62%-66%), followed by scaling and root planing (SRP) (44%-36%) and oral health procedures (OHP) (e.g., dental prophylaxis and dental probing without SRP) (27%-28%). Other ADL (flossing and chewing) (16%) and toothbrushing (8%-26%) resulted in bacteremia as well. The majority of studies had some concerns RCTs or moderate risk of bias nRCTs. Dental extractions, SRP and OHP, are associated with the highest frequency of bacteremia. Toothbrushing, flossing, and chewing also caused bacteremia in lower frequency.

5.
Circulation ; 144(12): 961-982, 2021 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-34255973

RESUMEN

BACKGROUND: Cardiovascular risk in diabetes remains elevated despite glucose-lowering therapies. We hypothesized that hyperglycemia induces trained immunity in macrophages, promoting persistent proatherogenic characteristics. METHODS: Bone marrow-derived macrophages from control mice and mice with diabetes were grown in physiological glucose (5 mmol/L) and subjected to RNA sequencing (n=6), assay for transposase accessible chromatin sequencing (n=6), and chromatin immunoprecipitation sequencing (n=6) for determination of hyperglycemia-induced trained immunity. Bone marrow transplantation from mice with (n=9) or without (n=6) diabetes into (normoglycemic) Ldlr-/- mice was used to assess its functional significance in vivo. Evidence of hyperglycemia-induced trained immunity was sought in human peripheral blood mononuclear cells from patients with diabetes (n=8) compared with control subjects (n=16) and in human atherosclerotic plaque macrophages excised by laser capture microdissection. RESULTS: In macrophages, high extracellular glucose promoted proinflammatory gene expression and proatherogenic functional characteristics through glycolysis-dependent mechanisms. Bone marrow-derived macrophages from diabetic mice retained these characteristics, even when cultured in physiological glucose, indicating hyperglycemia-induced trained immunity. Bone marrow transplantation from diabetic mice into (normoglycemic) Ldlr-/- mice increased aortic root atherosclerosis, confirming a disease-relevant and persistent form of trained innate immunity. Integrated assay for transposase accessible chromatin, chromatin immunoprecipitation, and RNA sequencing analyses of hematopoietic stem cells and bone marrow-derived macrophages revealed a proinflammatory priming effect in diabetes. The pattern of open chromatin implicated transcription factor Runt-related transcription factor 1 (Runx1). Similarly, transcriptomes of atherosclerotic plaque macrophages and peripheral leukocytes in patients with type 2 diabetes were enriched for Runx1 targets, consistent with a potential role in human disease. Pharmacological inhibition of Runx1 in vitro inhibited the trained phenotype. CONCLUSIONS: Hyperglycemia-induced trained immunity may explain why targeting elevated glucose is ineffective in reducing macrovascular risk in diabetes and suggests new targets for disease prevention and therapy.


Asunto(s)
Aterosclerosis/inmunología , Diabetes Mellitus Experimental/inmunología , Hiperglucemia/inmunología , Inmunidad Celular/inmunología , Leucocitos Mononucleares/inmunología , Macrófagos/inmunología , Animales , Aterosclerosis/patología , Células Cultivadas , Diabetes Mellitus Experimental/patología , Endarterectomía Carotidea , Humanos , Hiperglucemia/patología , Leucocitos Mononucleares/patología , Macrófagos/patología , Ratones , Ratones de la Cepa 129 , Ratones Transgénicos
6.
Catheter Cardiovasc Interv ; 99(2): 305-313, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-33942478

RESUMEN

OBJECTIVES: To describe outcomes following percutaneous coronary intervention (PCI) in patients who would usually have undergone coronary artery bypass grafting (CABG). BACKGROUND: In the United Kingdom, cardiac surgery for coronary artery disease (CAD) was dramatically reduced during the first wave of the COVID-19 pandemic. Many patients with "surgical disease" instead underwent PCI. METHODS: Between 1 March 2020 and 31 July 2020, 215 patients with recognized "surgical" CAD who underwent PCI were enrolled in the prospective UK-ReVasc Registry (ReVR). 30-day major cardiovascular event outcomes were collected. Findings in ReVR patients were directly compared to reference PCI and isolated CABG pre-COVID-19 data from British Cardiovascular Intervention Society (BCIS) and National Cardiac Audit Programme (NCAP) databases. RESULTS: ReVR patients had higher incidence of diabetes (34.4% vs 26.4%, P = .008), multi-vessel disease with left main stem disease (51.4% vs 3.0%, P < .001) and left anterior descending artery involvement (94.8% vs 67.2%, P < .001) compared to BCIS data. SYNTAX Score in ReVR was high (mean 28.0). Increased use of transradial access (93.3% vs 88.6%, P = .03), intracoronary imaging (43.6% vs 14.4%, P < .001) and calcium modification (23.6% vs 3.5%, P < .001) was observed. No difference in in-hospital mortality was demonstrated compared to PCI and CABG data (ReVR 1.4% vs BCIS 0.7%, P = .19; vs NCAP 1.0%, P = .48). Inpatient stay was half compared to CABG (3.0 vs 6.0 days). Low-event rates in ReVR were maintained to 30-day follow-up. CONCLUSIONS: PCI undertaken using contemporary techniques produces excellent short-term results in patients who would be otherwise CABG candidates. Longer-term follow-up is essential to determine whether these outcomes are maintained over time.


Asunto(s)
COVID-19 , Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Puente de Arteria Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Hirudinas , Humanos , Pandemias , Estudios Prospectivos , Proteínas Recombinantes , Sistema de Registros , SARS-CoV-2 , Resultado del Tratamiento
7.
Proc Natl Acad Sci U S A ; 114(10): 2562-2567, 2017 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-28223524

RESUMEN

ß-Arrestins (ßarrs) interact with G protein-coupled receptors (GPCRs) to desensitize G protein signaling, to initiate signaling on their own, and to mediate receptor endocytosis. Prior structural studies have revealed two unique conformations of GPCR-ßarr complexes: the "tail" conformation, with ßarr primarily coupled to the phosphorylated GPCR C-terminal tail, and the "core" conformation, where, in addition to the phosphorylated C-terminal tail, ßarr is further engaged with the receptor transmembrane core. However, the relationship of these distinct conformations to the various functions of ßarrs is unknown. Here, we created a mutant form of ßarr lacking the "finger-loop" region, which is unable to form the core conformation but retains the ability to form the tail conformation. We find that the tail conformation preserves the ability to mediate receptor internalization and ßarr signaling but not desensitization of G protein signaling. Thus, the two GPCR-ßarr conformations can carry out distinct functions.


Asunto(s)
Endocitosis/genética , Proteínas Mutantes/química , Receptores Acoplados a Proteínas G/química , beta-Arrestinas/química , Secuencia de Aminoácidos/genética , Reguladores de Proteínas de Unión al GTP/genética , Células HEK293 , Humanos , Conformación Molecular , Complejos Multiproteicos , Proteínas Mutantes/genética , Receptores Acoplados a Proteínas G/genética , beta-Arrestinas/genética
8.
Eur Heart J ; 40(38): 3143-3153, 2019 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-31329852

RESUMEN

AIMS: Owing to new evidence from randomized controlled trials (RCTs) in low-risk patients with severe aortic stenosis, we compared the collective safety and efficacy of transcatheter aortic valve implantation (TAVI) vs. surgical aortic valve replacement (SAVR) across the entire spectrum of surgical risk patients. METHODS AND RESULTS: The meta-analysis is registered with PROSPERO (CRD42016037273). We identified RCTs comparing TAVI with SAVR in patients with severe aortic stenosis reporting at different follow-up periods. We extracted trial, patient, intervention, and outcome characteristics following predefined criteria. The primary outcome was all-cause mortality up to 2 years for the main analysis. Seven trials that randomly assigned 8020 participants to TAVI (4014 patients) and SAVR (4006 patients) were included. The combined mean STS score in the TAVI arm was 9.4%, 5.1%, and 2.0% for high-, intermediate-, and low surgical risk trials, respectively. Transcatheter aortic valve implantation was associated with a significant reduction of all-cause mortality compared to SAVR {hazard ratio [HR] 0.88 [95% confidence interval (CI) 0.78-0.99], P = 0.030}; an effect that was consistent across the entire spectrum of surgical risk (P-for-interaction = 0.410) and irrespective of type of transcatheter heart valve (THV) system (P-for-interaction = 0.674). Transcatheter aortic valve implantation resulted in lower risk of strokes [HR 0.81 (95% CI 0.68-0.98), P = 0.028]. Surgical aortic valve replacement was associated with a lower risk of major vascular complications [HR 1.99 (95% CI 1.34-2.93), P = 0.001] and permanent pacemaker implantations [HR 2.27 (95% CI 1.47-3.64), P < 0.001] compared to TAVI. CONCLUSION: Compared with SAVR, TAVI is associated with reduction in all-cause mortality and stroke up to 2 years irrespective of baseline surgical risk and type of THV system.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Anciano de 80 o más Años , Femenino , Prótesis Valvulares Cardíacas , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Implantación de Prótesis de Válvulas Cardíacas/estadística & datos numéricos , Humanos , Masculino , Complicaciones Posoperatorias , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Reemplazo de la Válvula Aórtica Transcatéter/estadística & datos numéricos
9.
Chem Rev ; 116(14): 8173-92, 2016 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-27398715

RESUMEN

We begin with a brief historical review of the development of our understanding of the normal ordering of nd orbitals of a transition metal interacting with ligands, the most common cases being three below two in an octahedral environment, two below three in tetrahedral coordination, and four below one in a square-planar environment. From the molecular orbital construction of these ligand field splittings evolves a strategy for inverting the normal order: the obvious way to achieve this is to raise the ligand levels above the metal d's; that is, make the ligands better Lewis bases. However, things are not so simple, for such metal/ligand level placement may lead to redox processes. For 18-electron octahedral complexes one can create the inverted situation, but it manifests itself in the makeup of valence orbitals (are they mainly on metal or ligands?) rather than energy. One can also see the effect, in small ways, in tetrahedral Zn(II) complexes. We construct several examples of inverted ligand field systems with a hypothetical but not unrealistic AlCH3 ligand and sketch the consequences of inversion on reactivity. Special attention is paid to the square-planar case, exemplified by [Cu(CF3)4](-), in which Snyder had the foresight to see a case of an inverted field, with the empty valence orbital being primarily ligand centered, the dx2-y2 orbital heavily occupied, in what would normally be called a Cu(III) complex. For [Cu(CF3)4](-) we provide theoretical evidence from electron distributions, geometry of the ligands, thermochemistry of molecule formation, and the energetics of abstraction of a CF3 ligand by a base, all consistent with oxidation of the ligands in this molecule. In [Cu(CF3)4](-), and perhaps more complexes on the right side of the transition series than one has imagined, some ligands are σ-noninnocent. Exploration of inverted ligand fields helps us see the continuous, borderless transition from transition metal to main group bonding. We also give voice to a friendly disagreement on oxidation states in these remarkable molecules.


Asunto(s)
Complejos de Coordinación/química , Modelos Químicos , Materiales Biomiméticos/química , Bases de Lewis/química , Ligandos , Metales Pesados/química , Metales Ligeros/química , Estructura Molecular , Oxidación-Reducción , Teoría Cuántica
10.
Lancet ; 387(10021): 882-93, 2016 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-26341945

RESUMEN

Infective endocarditis occurs worldwide, and is defined by infection of a native or prosthetic heart valve, the endocardial surface, or an indwelling cardiac device. The causes and epidemiology of the disease have evolved in recent decades with a doubling of the average patient age and an increased prevalence in patients with indwelling cardiac devices. The microbiology of the disease has also changed, and staphylococci, most often associated with health-care contact and invasive procedures, have overtaken streptococci as the most common cause of the disease. Although novel diagnostic and therapeutic strategies have emerged, 1 year mortality has not improved and remains at 30%, which is worse than for many cancers. Logistical barriers and an absence of randomised trials hinder clinical management, and longstanding controversies such as use of antibiotic prophylaxis remain unresolved. In this Seminar, we discuss clinical practice, controversies, and strategies needed to target this potentially devastating disease.


Asunto(s)
Endocarditis , Adulto , Anciano , Anciano de 80 o más Años , Ecocardiografía , Endocarditis/diagnóstico , Endocarditis/epidemiología , Endocarditis/microbiología , Endocarditis/fisiopatología , Endocarditis/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
11.
J Biol Chem ; 290(43): 25907-19, 2015 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-26370078

RESUMEN

We have reported previously that a missense mutation in the mitochondrial fission gene Dynamin-related protein 1 (Drp1) underlies the Python mouse model of monogenic dilated cardiomyopathy. The aim of this study was to investigate the consequences of the C452F mutation on Drp1 protein function and to define the cellular sequelae leading to heart failure in the Python monogenic dilated cardiomyopathy model. We found that the C452F mutation increased Drp1 GTPase activity. The mutation also conferred resistance to oligomer disassembly by guanine nucleotides and high ionic strength solutions. In a mouse embryonic fibroblast model, Drp1 C452F cells exhibited abnormal mitochondrial morphology and defective mitophagy. Mitochondria in C452F mouse embryonic fibroblasts were depolarized and had reduced calcium uptake with impaired ATP production by oxidative phosphorylation. In the Python heart, we found a corresponding progressive decline in oxidative phosphorylation with age and activation of sterile inflammation. As a corollary, enhancing autophagy by exposure to a prolonged low-protein diet improved cardiac function in Python mice. In conclusion, failure of Drp1 disassembly impairs mitophagy, leading to a downstream cascade of mitochondrial depolarization, aberrant calcium handling, impaired ATP synthesis, and activation of sterile myocardial inflammation, resulting in heart failure.


Asunto(s)
Biopolímeros/fisiología , Dinaminas/fisiología , Insuficiencia Cardíaca/etiología , Mitofagia , Miocarditis/etiología , Animales , Biopolímeros/genética , Biopolímeros/metabolismo , Células Cultivadas , Dinaminas/genética , Dinaminas/metabolismo , Insuficiencia Cardíaca/fisiopatología , Ratones , Mutación , Miocarditis/fisiopatología , Fosforilación Oxidativa
14.
Circ Res ; 113(6): 660-75, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-23989711

RESUMEN

Despite the striking advances in medical and surgical therapy, the morbidity, mortality, and economic burden of heart failure (HF) remain unacceptably high. There is increasing evidence that the risk and course of HF depend on genetic predisposition; however, the genetic contribution to HF is heterogeneous and complex. At one end of the spectrum are the familial monogenic HF syndromes in which causative mutations are rare but highly penetrant. At the other, HF susceptibility and course may be influenced by more common, less penetrant genetic variants. As detailed in this review, efforts to unravel the basis of the familial cardiomyopathies at the mendelian end of the spectrum already have begun to deliver on the promise of informative mechanisms, novel gene-based diagnostics, and therapies for distinct subtypes of HF. However, continued progress requires the differentiation of pathogenic mutations, disease modifiers, and rare, benign variants in the deluge of data emerging from increasingly accessible novel sequencing technologies. This represents a significant challenge and demands a sustained effort in analysis of extended family pedigrees, diligent clinical phenotyping, and systematic annotation of human genetic variation.


Asunto(s)
Cardiomiopatías/genética , Insuficiencia Cardíaca/etiología , Cardiomiopatías/complicaciones , Cardiomiopatías/metabolismo , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Humanos , Mutación , Contracción Miocárdica/genética
15.
Proc Natl Acad Sci U S A ; 109(45): 18295-9, 2012 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-23091019

RESUMEN

We have applied an ambient ionization technique, desorption electrospray ionization MS, to identify transient reactive species of an archetypal C-H amination reaction catalyzed by a dirhodium tetracarboxylate complex. Using this analytical method, we have detected previously proposed short-lived reaction intermediates, including two nitrenoid complexes that differ in oxidation state. Our findings suggest that an Rh-nitrene oxidant can react with hydrocarbon substrates through a hydrogen atom abstraction pathway and raise the intriguing possibility that two catalytic C-H amination pathways may be operative in a typical bulk solution reaction. As highlighted by these results, desorption electrospray ionization MS should have broad applicability for the mechanistic study of catalytic processes.

16.
Proc Natl Acad Sci U S A ; 109(7): 2246-50, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22315417

RESUMEN

Desorption electrospray ionization (DESI) coupled to high-resolution Orbitrap mass spectrometry (MS) was used to study the reactivity of a (ß-amino alcohol)(arene)RuCl transfer hydrogenation catalytic precursor in methanol (CH(3)OH). By placing [(p-cymene)RuCl(2)](2) on a surface and spraying a solution of ß-amino alcohol in methanol, two unique transient intermediates having lifetimes in the submillisecond to millisecond range were detected. These intermediates were identified as Ru (II) and Ru (IV) complexes incorporating methyl formate (HCOOCH(3)). The Ru (IV) intermediate is not observed when the DESI spray solution is sparged with Ar gas, indicating that O(2) dissolved in the solvent is necessary for oxidizing Ru (II) to Ru (IV). These proposed intermediates are supported by high-resolution and high mass accuracy measurements and by comparing experimental to calculated isotope profiles. Additionally, analyzing the bulk reaction mixture using gas chromatography-MS and nuclear magnetic resonance spectroscopy confirms the formation of HCOOCH(3). These results represent an example that species generated from the (ß-amino alcohol)(arene)RuCl (II) catalytic precursor can selectively oxidize CH(3)OH to HCOOCH(3). This observation leads us to propose a pathway that can compete with the hydrogen transfer catalytic cycle. Although bifunctional hydrogen transfer with Ru catalysts has been well-studied, the ability of DESI to intercept intermediates formed in the first few milliseconds of a chemical reaction allowed identification of previously unrecognized intermediates and reaction pathways in this catalytic system.

17.
Ann Plast Surg ; 75(5): 572-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25393499

RESUMEN

BACKGROUND: Craniomaxillofacial (CMF) fractures are typically treated with open reduction and internal fixation. Open reduction and internal fixation can be complicated by hardware exposure or infection. The literature often does not differentiate between these 2 entities; so for this study, we have considered all hardware exposures as hardware infections. Approximately 5% of adults with CMF trauma are thought to develop hardware infections. Management consists of either removing the hardware versus leaving it in situ. The optimal approach has not been investigated. Thus, a systematic review of the literature was undertaken and a resultant evidence-based approach to the treatment and management of CMF hardware infections was devised. MATERIALS AND METHODS: A comprehensive search of journal articles was performed in parallel using MEDLINE, Web of Science, and ScienceDirect electronic databases. Keywords and phrases used were maxillofacial injuries; facial bones; wounds and injuries; fracture fixation, internal; wound infection; and infection. Our search yielded 529 articles. To focus on CMF fractures with hardware infections, the full text of English-language articles was reviewed to identify articles focusing on the evaluation and management of infected hardware in CMF trauma. Each article's reference list was manually reviewed and citation analysis performed to identify articles missed by the search strategy. There were 259 articles that met the full inclusion criteria and form the basis of this systematic review. The articles were rated based on the level of evidence. There were 81 grade II articles included in the meta-analysis. RESULT: Our meta-analysis revealed that 7503 patients were treated with hardware for CMF fractures in the 81 grade II articles. Hardware infection occurred in 510 (6.8%) of these patients. Of those infections, hardware removal occurred in 264 (51.8%) patients; hardware was left in place in 166 (32.6%) patients; and in 80 (15.6%) cases, there was no report as to hardware management. Finally, our review revealed that there were no reported differences in outcomes between groups. CONCLUSIONS: Management of CMF hardware infections should be performed in a sequential and consistent manner to optimize outcome. An evidence-based algorithm for management of CMF hardware infections based on this critical review of the literature is presented and discussed.


Asunto(s)
Remoción de Dispositivos/métodos , Fijación Interna de Fracturas/instrumentación , Fijadores Internos , Traumatismos Maxilofaciales/cirugía , Fracturas Craneales/cirugía , Algoritmos , Técnicas de Apoyo para la Decisión , Humanos , Fracturas Maxilares/cirugía , Resultado del Tratamiento
18.
Catheter Cardiovasc Interv ; 83(4): 556-9, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24532328

RESUMEN

We report a case of endovascular snare retrieval of a new stainless steel vascular closure device (Celt ACD(®) , Kimal, Middlesex, UK) from the common femoral artery, following device failure after diagnostic coronary angiography. The stainless steel composition of the device aided successful fluoroscopic localization and removal.


Asunto(s)
Angiografía Coronaria/efectos adversos , Remoción de Dispositivos/métodos , Arteria Femoral , Hemorragia/prevención & control , Técnicas Hemostáticas/instrumentación , Radiografía Intervencional/métodos , Anciano , Diseño de Equipo , Falla de Equipo , Femenino , Arteria Femoral/diagnóstico por imagen , Fluoroscopía , Hemorragia/diagnóstico , Hemorragia/etiología , Humanos , Punciones , Acero Inoxidable , Resultado del Tratamiento
19.
J Invasive Cardiol ; 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38471155

RESUMEN

OBJECTIVES: Cardiac surgery for coronary artery disease was dramatically reduced during the first wave of the COVID-19 pandemic. Many patients with disease ordinarily treated with coronary artery bypass grafting (CABG) instead underwent percutaneous coronary intervention (PCI). We sought to describe 12-month outcomes following PCI in patients who would typically have undergone CABG. METHODS: Between March 1 and July 31, 2020, patients who received revascularization with PCI when CABG would have been the primary choice of revascularization were enrolled in the prospective, multicenter UK-ReVasc Registry. We evaluated the following major adverse cardiovascular events at 12 months: all-cause mortality, myocardial infarction, repeat revascularization, stroke, major bleeding, and stent thrombosis. RESULTS: A total of 215 patients were enrolled across 45 PCI centers in the United Kingdom. Twelve-month follow up data were obtained for 97% of the cases. There were 9 deaths (4.3%), 5 myocardial infarctions (2.4%), 12 repeat revascularizations (5.7%), 1 stroke (0.5%), 3 major bleeds (1.4%), and no cases of stent thrombosis. No difference in the primary endpoint was observed between patients who received complete vs incomplete revascularization (residual SYNTAX score £ 8 vs > 8) (P = .22). CONCLUSIONS: In patients with patterns of coronary disease in whom CABG would have been the primary therapeutic choice outside of the pandemic, PCI was associated with acceptable outcomes at 12 months of follow-up. Contemporary randomized trials that compare PCI to CABG in such patient cohorts may be warranted.

20.
Anesthesiology ; 119(2): 270-83, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23528538

RESUMEN

BACKGROUND: It is unclear whether postoperative B-type natriuretic peptides (i.e., BNP and N-terminal proBNP) can predict cardiovascular complications in noncardiac surgery. METHODS: The authors undertook a systematic review and individual patient data meta-analysis to determine whether postoperative BNPs predict postoperative cardiovascular complications at 30 and 180 days or more. RESULTS: The authors identified 18 eligible studies (n = 2,051). For the primary outcome of 30-day mortality or nonfatal myocardial infarction, BNP of 245 pg/ml had an area under the curve of 0.71 (95% CI, 0.64-0.78), and N-terminal proBNP of 718 pg/ml had an area under the curve of 0.80 (95% CI, 0.77-0.84). These thresholds independently predicted 30-day mortality or nonfatal myocardial infarction (adjusted odds ratio [AOR] 4.5; 95% CI, 2.74-7.4; P < 0.001), mortality (AOR, 4.2; 95% CI, 2.29-7.69; P < 0.001), cardiac mortality (AOR, 9.4; 95% CI, 0.32-254.34; P < 0.001), and cardiac failure (AOR, 18.5; 95% CI, 4.55-75.29; P < 0.001). For greater than or equal to 180-day outcomes, natriuretic peptides independently predicted mortality or nonfatal myocardial infarction (AOR, 3.3; 95% CI, 2.58-4.3; P < 0.001), mortality (AOR, 2.2; 95% CI, 1.67-86; P < 0.001), cardiac mortality (AOR, 2.1; 95% CI, 0.05-1,385.17; P < 0.001), and cardiac failure (AOR, 3.5; 95% CI, 1.0-9.34; P = 0.022). Patients with BNP values of 0-250, greater than 250-400, and greater than 400 pg/ml suffered the primary outcome at a rate of 6.6, 15.7, and 29.5%, respectively. Patients with N-terminal proBNP values of 0-300, greater than 300-900, and greater than 900 pg/ml suffered the primary outcome at a rate of 1.8, 8.7, and 27%, respectively. CONCLUSIONS: Increased postoperative BNPs are independently associated with adverse cardiac events after noncardiac surgery.


Asunto(s)
Cardiopatías/sangre , Cardiopatías/epidemiología , Péptido Natriurético Encefálico/sangre , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/epidemiología , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Cardiopatías/mortalidad , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/mortalidad , Humanos , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/epidemiología , Infarto del Miocardio/mortalidad , Oportunidad Relativa , Complicaciones Posoperatorias/mortalidad , Periodo Posoperatorio , Curva ROC , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Factores de Riesgo
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