pinecone/core-2020-05-10-deduplication huggingface dataset:
Determinants of fluoroscopy time for invasive coronary angiography and percutaneous coronary intervention: Insights from the NCDR ®

Objectives  Identifying the distributions and determinants of fluoroscopy time for invasive coronary angiography (ICA) and percutaneous coronary intervention (PCI).    Background  ICA and PCI are significant contributors to radiation exposure from medical imaging in the US. Fluoroscopy time is a potentially modifiable determinant of radiation exposure for these procedures, but has not been well characterized in contemporary practice.    Methods  We evaluated the distribution of fluoroscopy time in patients undergoing ICA and/or PCI in the CathPCI Registry ® , stratifying patients by numerous clinical scenarios. Hierarchical models were used to determine patient, procedure, operator and hospital‐level factors associated with fluoroscopy time for these procedures.    Results  Our study included a total of 3,295,348 ICA and PCI procedures performed by 9,600 operators from January 2005 through June 2009. There was wide variation in fluoroscopy times for these procedures with median [IQR] fluoroscopy times of 2.6 [1.7–4.5] minutes for ICA, 6.7 [4.2–10.8] minutes for ICA in patients with prior coronary artery bypass grafting (CABG), 10.1 [6.0–17.4] minutes for PCI, 10.7 [7.0–16.9] minutes for PCI with ICA, and 16.0 [10.6–24.0] minutes for PCI and ICA in patients with prior CABG. Prolonged fluoroscopy times (>30 minutes) were rare for ICA, but occurred in 6.7% of PCIs and 14.7% of PCIs in patients with prior CABG. After accounting for patient characteristics and procedure complexity, operator and hospital‐level factors explained nearly 20% of the variation in fluoroscopy time.    Conclusions  Fluoroscopy times vary widely during ICA and PCI with operator and hospital‐level factors contributing substantially to these differences. A better understanding of potentially modifiable sources of this variation will elucidate opportunities for enhancing the radiation safety of these procedures. © 2013 Wiley Periodicals, Inc
Initial experience with the cook formula balloon expandable stent in congenital heart disease

INTRODUCTION: Balloon expandable stents are an integral part in the catheter treatment of congenital heart disease. In the growing child, stents require dilatation to greater diameters over time. The Cook Formula stent is a recent 316 stainless steel open-cell design licensed for peripheral vascular work.\ud
METHODS: Following extensive ex vivo studies, 112 stents were implanted in 97 children [median age 3.9 (0.01-17.6) years; median weight 13.7 (2.4-62.8) kg] over a 27-month (Oct 2011-Dec 2013) period.\ud
RESULTS: Bench testing revealed that there was no stent shortening for dilatation to nominal diameter and beyond. The 5 mm stents could be dilated up to 10 mm, and the 10 mm stents to 20 mm. Stents were implanted through 4-7F sheaths or guide catheters over appropriate wires. Stent tracking and delivery was excellent. Twenty-three stents were implanted in the right ventricular outflow tract in Fallot-type lesions, 53 for branch pulmonary artery stenosis (22 post cavopulmonary shunt/Fontan), 14 conduit stenosis, 13 Fontan fenestrations, 3 PDA in hybrid stage I Norwood, 5 in coarctation, and 1 for SVC obstruction. Sixty-one stents (54%) were overdilated. There were no stent fractures. Radial strength was very good, whereas stent conformability was limited.\ud
CONCLUSIONS: The Cook Formula stent is a premounted balloon-expandable stent that can be significantly overdilated with virtually no shortening allowing for precise placement and minimal protrusion into adjacent vessels. The Formula stent is a very versatile addition to the range of stents for use in the catheter treatment of complex congenital heart disease in children. © 2014 Wiley Periodicals, Inc
Two-in-one aortic valve sizing and valvuloplasty conductance balloon catheter

BACKGROUND: Inaccurate aortic valve sizing and selection is linked to paravalvular leakage in transcatheter aortic valve replacement (TAVR). Here, a novel sizing valvuloplasty conductance balloon (SVCB) catheter is shown to be accurate, reproducible, unbiased, and provides real-time tool for aortic valve sizing that fits within the standard valvuloplasty procedure.
METHODS AND RESULTS: The SVCB catheter is a valvuloplasty device that uses real-time electrical conductance measurements based on Ohm's Law to size the balloon opposed against the aortic valve at any given inflation pressure. Accuracy and repeatability of the SVCB catheter was performed on the bench in phantoms of known dimension and ex vivo in three domestic swine aortic annuli with comparison to computed tomography (CT) and dilator measurements. Procedural workflow and safety was demonstrated in vivo in three additional domestic swine. SVCB catheter measurements had negligible bias or error for bench accuracy considered as the gold standard (Bias: -0.11 ± 0.26 mm; Error: 1.2%), but greater disagreement in ex vivo versus dilators (Bias: -0.3 ± 1.1 mm; Error: 4.5%), and ex vivo versus CT (Bias: -1.0 ± 1.6 mm; Error: 8.7%). The dilator versus CT accuracy showed similar agreement (Bias: -0.9 ± 1.5 mm; Error: 7.3%). Repeatability was excellent on the bench (Bias: 0.02 ± 0.12 mm; Error: 0.5%) and ex vivo (Bias: -0.4 ± 0.9 mm; Error: 4.6%). In animal studies, the device fit well within the procedural workflow with no adverse events or complications.
CONCLUSIONS: Due to the clinical relevance of this accurate, repeatable, unbiased, and real-time sizing measurement, the SVCB catheter may provide a useful tool prior to TAVR. These findings merit a future human study
Percutaneous Occlusion of Vascular Malformations in Pediatric and Adult Patients: 20-Year Experience of a Single Center

OBJECTIVE:
A case series on different vascular malformations (VM) treated with percutaneous occlusion in children and adults is presented.
BACKGROUND:
Percutaneous occlusion is usually the preferred treatment method for VM. Previous series have mostly focused on single types of devices and/or VM.
METHODS:
Retrospective analysis of all patients who underwent percutaneous occlusion of VM in a single center, from 1995 to 2014, excluding patent ductus arteriosus. Clinical and angiographic data, procedural details, implanted devices, and complications were assessed. Procedural success was defined as effective device deployment with none or minimal residual flow. Predictors of procedural failure and complications were determined by multivariate analysis.
RESULTS:
A total of 123 VM were intervened in 47 patients with median age of 12 years (25 days-76 years). The VM included 55 pulmonary arteriovenous fistulae, 39 aortopulmonary collaterals, 10 systemic venovenous collaterals, 8 peripheral arteriovenous fistulae, 5 Blalock-Taussig shunts, 4 coronary fistulae, and 2 Fontan fenestrations. The 143 devices used included 80 vascular plugs, 38 coils, 22 duct occluders, and 3 foramen ovale or atrial septal defect occluders. Median vessel size was 4.5 (2.0-16.0) mm and device/vessel size ratio was 1.4 (1.1-2.0). Successful occlusion was achieved in 118 (95.9%) VM, including three reinterventions. Four (3.3%) clinically relevant complications occurred, without permanent sequelae. Lower body weight was independently associated with procedural failure and complications.
CONCLUSION:
To our knowledge, this is the largest series on different VM occluded percutaneously in children and adults, excluding patent ductus arteriosus. Percutaneous occlusion was effective and safe, using different devices.info:eu-repo/semantics/publishedVersio
T315I clone selection in a Ph+ all patient under low-dose ponatinib maintenance.

We report here the clinical course of a Ph+ ALL patient who was treated with ponatinib 15 mg/day, as maintenance therapy, and developed a BCR-ABL T315I mutation leading to ALL relapse. This clonal evolution was reversed, without adverse effects, by increasing ponatinib to 45 mg/day. To our knowledge, we have been confronted with the first clinical case of a T315I clonal selection of ALL caused by subeffective therapeutic level of the drug. This single patient experience highlights the risk of T315I clone selection in Ph+ ALL treated with reduced dose ponatinib
Thyrotoxicosis in a 13-year-old girl following pituitary adenectomy for Cushing's disease.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesOur objective is to report a case of thyrotoxicosis following pituitary adenectomy for Cushing's disease, the only pediatric case to our knowledge. No thyroid antibodies were detected, and the thyrotoxicosis was successfully treated for 3 months with no relapse after 5 years of follow-up. The cause of thyrotoxicosis remains unknown
Williams-Beuren syndrome: pitfalls for diagnosis in limited resources setting

Patients with Williams-Beuren Syndrome can be recognized clinically, given the characteristic dysmorphism, intellectual disability, and behavior. We report on a Congolese boy with typical WBS facial characteristics. He suffered meningitis and coma at the age of 2 years then subsequently presented with profound intellectual disability and atypical behavior. The WBS was only made at age 8.2 years and confirmed with FISH testing and microarray-CGH. The present report aims to warn clinicians that infections may associate and/or modify a genetic disease as this may be observed in developing countries given the prevalence of infectious diseases.status: publishe
Long-term survival in multiple myeloma.

KEY CLINICAL MESSAGE:
The survival of multiple myeloma patients has improved very significantly over the last decade. Still median overall survival is inferior to 5 years. A small proportion of patients survive longer than 10 years. In this paper we discuss four cases illustrating the nonhomogeneous clinical presentation and evolution of this subset of patients. Surprisingly, these long survivors do not always have deep responses and some require frequent treatments, which include autologous stem cell transplantation and novel drugs. The authors discuss several aspects of these clinical histories, including treatment options, raising hypothesis on their relation with long survivorship which may be important to have in consideration when studying this subject
MECHANISTIC INVESTIGATIONS OF TRANSITION METAL CATALYZED REACTIONS

Transition metal catalyzed reactions have had a large impact on the human progress for the last century. Several extremely important areas, such as the agricultural industry and the plastic industry, have benefited from this development. The evolution of different transition metal catalysts has also been very important for the pharmaceutical industry. One vital factor when developing new and more effective catalysts is to obtain mechanistic insights. In this thesis, several different methods to investigate mechanisms for transition metal catalyzed reactions are presented.
The factors controlling regioselectivity for a palladium catalyzed allylic alkylation has been studied. Pre-formed (η3-allyl)Pd complexes were used to minimize dynamic processes. In the study it was found that the regioselectivity depends mainly on steric interactions, rather than electronic effects. For complexes with less steric hindrance, the trans effect controlls the selectivity.  Furthermore, the mechanism for a sulfinyl nucleophile, employed in the same type of reaction, has been studied and the mode of attack has been revealed. The importance of a fast palladium catalyzed Mislow-Braverman-Evans rearrangement to ensure that the correct product was formed, was also disclosed.
The important Mizoroki-Heck reaction has been investigated in two different studies. The first study revealed the mechanistic pathway for a Pd(II) catalyzed domino Mizoroki-Heck-Suzuki diarylation reaction. The dependence of benzoquinone as the re-oxidant, in order to achieve the diarylation product, was explained by its ability to coordinate to the palladium moiety, thereby allowing access to a new low-energy pathway to the product. In the second study, a new and mild nickel catalyzed variant of the Mizoroki-Heck reaction was presented and the mechanistic pathway for the reaction was introduced. In addition to this, the reasons for several unsuccessful conditions and additives were uncovered.
The development of new, environmentally more benign, catalysts for cross coupling reactions is important. Iron is one of the most promising metals for this purpose, but the mechanistic knowledge of this reaction is still not comprehensive. In this thesis, several mechanistic and computational studies reveal new insights into this reaction, paving the way to develop new and more effective catalysts and conditions for the reaction
Deactivation of TEM-1 beta-Lactamase investigated by isothermal batch and non-isothermal continuous enzyme membrane reactor methods

The thermal deactivation of TEM-1 β-lactamase was examined using two experimental techniques: a series of isothermal batch assays and a single, continuous, non-isothermal assay in an enzyme membrane reactor (EMR). The isothermal batch-mode technique was coupled with the three-state  Equilibrium Model  of enzyme deactivation, while the results of the EMR experiment were fitted to a four-state  molten globule model . The two methods both led to the conclusions that the thermal deactivation of TEM-1 β -lactamase does not follow the Lumry-Eyring model and that the Teq of the enzyme (the point at which active and inactive states are present in equal amounts due to thermodynamic equilibrium) is at least 10 °C from the Tm (melting temperature), contrary to the idea that the true temperature optimum of a biocatalyst is necessarily close to the melting temperature
Liquid-phase hydrogenation of unsaturated aldehydes: enhancing selectivity of multiwalled carbon nanotube- supported catalysts by thermal activation

Platinum and iridium organometallic precursors are used to prepare nanosized, thermally stable multiwalled carbon nanotube-
supported catalysts. The materials are characterized by N2 adsorption at 77 K, temperature-programmed desorption coupled
with mass spectrometry, H2 chemisorption, transmission electron microscopy and thermogravimetric analysis; they are
tested in the selective hydrogenation of cinnamaldehyde to cinnamyl alcohol under mild conditions (363 K and 1 MPa). A thermal activation at 973 K is found to have a very positive effect over both activity and selectivity, leading to selectivities
of approximately 70%, at 50% conversion, regardless of the active metal phase (Pt or Ir). Since no noticeable differences in
the metal particle sizes are detected, the results are interpreted in light of an enhanced metal/support interaction. This effect, induced by the removal of oxygenated surface groups, is thought to change the adsorption mechanism of the cinnamaldehyde
molecule
A theoretical study of the mechanism of the desymmetrization of cyclic meso-anhydrides by chiral amino alcohols

The alcoholysis of cyclic meso-anhydrides catalyzed by β-amino alcohols has been investigated with DFT quantum mechanics to determine the mechanism of this reaction. Both nucleophilic catalysis and general base catalysis pathways are explored for methanol-induced ring opening of an anhydride catalyzed by a chiral amino alcohol. The nucleophilic pathway involves a late transition state with a high energy barrier. In this mechanism, methanolysis is expected to take place following the amine-induced ring opening of the anhydride. In the base-catalyzed mechanism, methanol attack on one carbonyl group of the meso-anhydride is assisted by the β-amino alcohol; the amine functionality abstracts the methanol proton. The chiral amino alcohol also catalyzes the reaction by stabilizing the oxyanion that forms upon ring opening of the anhydride by hydrogen bonding with its alcoholic moiety. Both stepwise and concerted pathways have been studied for the general base catalysis route. Transition structures for both are found to be lower in energy than in the nucleophilic mechanism. Overall this study has shed light on the mechanism of the β-amino alcohol-catalyzed alcoholysis of cyclic meso-anhydrides, showing that the nucleophilic pathway is approximately 100 kJ mol−1 higher in energy than the general base pathwa
SBA-16-Supported Cobalt Catalyst with High Activity and\ud
Stability for FischerâTropsch Synthesis

SBA-16 molecular sieves were used as support to prepare\ud
cobalt catalyst for FischerâTropsch synthesis (FTS). The catalysts were characterized by using TEM, power XRD, temperature-programmed reduction, and N2 adsorptionâdesorption. The analyses indicate that most of the Co3O4 nanoparticles were introduced into the SBA-16 cages, and the SBA-16 mesostructure was retained after cobalt impregnation. The Co/SBA-16 catalyst exhibited higher cobalt dispersion compared to theCo/SiO2 catalyst. The catalytic properties of the catalysts in FTS were evaluated in a fixed-bed reactor. The effect of the addition\ud
of water was measured in a continuously stirred tank reactor. High FTS activity and stability were observed on the SBA-16-supported catalyst. The SBA-16-supported cobalt catalyst shows low mobility of cobalt particles in the SBA-16 cages. Unlike silica, the SBA-16 support can efficiently prevent the aggregation and sintering of cobalt nanoparticles
Vanadium Catalyzed Synthesis of Cyclic Organic Carbonates

Vanadium complexes bearing easily synthesized, differently functionalized salen and salphen ligands were prepared and tested for their ability to catalyze the cycloaddition of carbon dioxide to epoxides resulting in cyclic organic carbonates. The reactivity of the prepared catalysts dramatically increases when a coordinating hydroxyl group is present as a substituent in the organic epoxide. The commercially available [VO(acac)2] complex was used as reference compound, and, in this case, we found that V10O26·(NBu4)4 was formed during the catalytic reactions. This compound, characterized by X-ray diffraction analysis, is likely the active catalyst, and it results in significantly better yields of cyclic carbonates compared to those obtained with Schiff base containing vanadyl complexes. The high activity of the mixed polyoxo vanadyl-vanadate complex\ud
marks it as a powerful catalyst within the context of CO2 fixation chemistry
Rhodium(I) complexes with hemilabile phosphines: Rational design for efficient oxidative amination catalysts

13 páginas, 10 figuras, 6 tablas, 4 esquemas.A series of cationic square-planar rhodium(I) complexes of type [Rh(cod){Ar2P(CH2)nZ}]+, [Rh(cod){Ar2P(CH2)nZ}2]+, and [Rh{Ar2P(CH2)nZ}2]+, which contained diverse functionalized hemilabile phosphine ligands of type Ar2P(CH2)nZ (n=1–3; Z=OMe, OEt, OnBu, NMe2, SMe), were synthesized and spectroscopically characterized. The crystal structures of representative compounds were determined by X-ray diffraction. Most complexes were active catalysts for the anti-Markovnikov oxidative amination of styrene with piperidine to produce (E)-1-styrylpiperidine. Catalyst screening showed a remarkable relationship between the hemilabile ligand, the precatalyst structure, and the catalytic activity. The more-efficient catalysts were those that had arylphosphine ligands with a 2-alkoxyethyl- or 3-alkoxypropyl hemilabile moiety, Ar2P(CH2)nOR (n=2, 3; R=Me, Et, nBu). This study has revealed the outstanding catalytic activity of bis-phosphine complexes [Rh{(4-R-C6H4)2P(CH2)3OEt}2][PF6] (R=H, Me, OMe), with unprecedented turnover frequencies of up to 80 h−1 (R=Me) and excellent enamine selectivity (96 %).Financial support from the Ministerio de Ciencia e Innovación (MICINN/FEDER): CTQ2010-15221, MULTICAT (CSD2009-00050), and Factoría de Cristalización (CSD2006-0015) is gratefully acknowledged. M.I.B. thanks the Spanish MICINN and the IUCH (Instituto Universitario de Catálisis Homogénea) for a predoctoral fellowship.Peer reviewe
Support effects in a Rh diamine complex heterogenized on carbon materials

The Rh diamine complex [Rh(COD)NH2(CH2)2NH(CH2)3Si(OCH3)3] BF4 was heterogenized by covalent bonding on two carbon xerogels and on carbon nanofibers, with the objective of preparing hydrogenation hybrid catalysts. Gas adsorption, SEM, TEM, DTP, ICP-OES and XPS were used for characterization. The results indicate that the active molecule is mainly located in supermicropores and produces microporosity blockage. The hybrid catalysts are more active than the homogeneous complex, but the Rh complex is partially reduced upon reaction. This modification is related to the nature of the support, which also shows effects in the stabilization against sintering of the Rh particles formed. The support porosity is a key factor in the selectivity differences between the catalysts.The authors thank the financial support to MICINN, Project MAT2009-07150, to GVA and FEDER, Project Prometeo 2009/047, and to MEC for the FPU scholarship of C.C.G
Base-free β-boration of α,β-unsaturated imines catalysed by Cu2O with concurrent enhancement of asymmetric induction.

The stereoselective synthesis of γ-aminoalcohols from the catalytic asymmetric β-boration of α,β-unsaturated imine precursors has been streamlined with the use of Cu2O as the catalyst, readily accessible (R)-(+)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl as the chiral ligand and no additional base. The new simplicity of the catalytic system has the added value of in situ formation of the imines, which allows access to cyclic and acyclic β-boryl imines. The reaction was followed by using in situ IR spectroscopy, which demonstrated the imine formation– β-boration sequence and that the new catalytic system is superior to those employed for this reaction previously
Microstructure of Bimetallic PtPd Catalysts under Oxidizing Conditions

Diesel oxidation catalysts (DOCs), which decrease the amount of harmful carbon monoxide (CO), nitrogen oxide (NO), and hydrocarbon (HC) emissions in engine exhaust, typically utilize Pt and Pd in the active phase. There is universal agreement that the addition of Pd improves both the catalytic performance and the durability of Pt catalysts. However, the mechanisms by which Pd improves the performance of Pt are less clear. Because these catalysts operate under oxidizing conditions, it is important to understand these catalysts in their working state. Herein, we report the microstructure of PtPd catalysts that are aged in air at 750 °C. After 10 h of aging, EXAFS and XANES analysis show that the Pt is fully reduced but that almost 30 % of the Pd species are present as an oxide. HRTEM images show no evidence of surface oxides on the metallic PtPd particles. Instead, the PdO is present as a separate phase that is dispersed over the alumina support. Within the metallic particles, Pt and Pd are uniformly distributed and there is no evidence of core–shell structures. Therefore, the improved catalytic performance is likely associated with the co‐existence of metallic Pt and Pd on the catalyst surface.     Structured learning:  A comparison of the evolution of aged and aged‐plus‐reduced Pt, Pd, and bimetallic PtPd particles is reported. The bimetallic particles grow in size and both Pt and Pd stay metallic in the form of large particles with a portion of Pd present as a dispersed Pd phase
Solvent- and Ligand-free Diboration of Alkynes and Alkenes Catalyzed by Platinum Nanoparticles on Titania

Platinum nanoparticles supported on titania efficiently catalyzed the diboration of alkynes and alkenes under solvent- and ligand-free conditions in air. The cis-1,2-diborylalkenes and 1,2-diborylalkanes were obtained in moderate to excellent yields following, in most cases, a simple filtration workup protocol. The versatility of the cis-1,2-diboronvinyl compounds was demonstrated in a series of organic transformations, including the Suzuki–Miyaura cross coupling and the boron–halogen exchange.This work was generously supported by the Spanish Ministerio de Economía y Competitividad (MINECO; CTQ2007-65218 and CTQ2011-24151), the Generalitat Valenciana (GV; PROMETEO/2009/002 and PROMETEO/2009/039), and FEDER