Among patients at intermediate risk for aortic-valve surgery, transcatheter aortic-valve replacement (TAVR) was noninferior to standard surgery, although each procedure had a different pattern of ...adverse events.
Transcatheter aortic-valve replacement (TAVR) with the use of a self-expanding prosthesis is superior to medical therapy in patients with severe, symptomatic aortic stenosis in whom surgical aortic-valve replacement has been associated with prohibitive risk.
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Among patients who are at high risk for standard surgery, TAVR may be the preferred option.
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The adoption of TAVR in patients with aortic stenosis at high risk for surgery has been rapid, as shown by enrollment in the ongoing Society of Thoracic Surgeons–American College of Cardiology Transcatheter Valve Therapy Registry.
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The comparative efficacy of TAVR and surgery has been less well studied among patients . . .
Enteroaggregative Escherichia coli (EAEC) represents a heterogeneous group of E. coli strains. The pathogenicity and clinical relevance of these bacteria are still controversial. In this review, we ...describe the clinical significance of EAEC regarding patterns of infection in humans, transmission, reservoirs, and symptoms. Manifestations associated with EAEC infection include watery diarrhea, mucoid diarrhea, low-grade fever, nausea, tenesmus, and borborygmi. In early studies, EAEC was considered to be an opportunistic pathogen associated with diarrhea in HIV patients and in malnourished children in developing countries. In recent studies, associations with traveler's diarrhea, the occurrence of diarrhea cases in industrialized countries, and outbreaks of diarrhea in Europe and Asia have been reported. In the spring of 2011, a large outbreak of hemolytic-uremic syndrome (HUS) and hemorrhagic colitis occurred in Germany due to an EAEC O104:H4 strain, causing 54 deaths and 855 cases of HUS. This strain produces the potent Shiga toxin along with the aggregative fimbriae. An outbreak of urinary tract infection associated with EAEC in Copenhagen, Denmark, occurred in 1991; this involved extensive production of biofilm, an important characteristic of the pathogenicity of EAEC. However, the heterogeneity of EAEC continues to complicate diagnostics and also our understanding of pathogenicity.
The Many Faces of Europeanization Olsen, Johan P.
Journal of common market studies,
December 2002, Letnik:
40, Številka:
5
Journal Article
Recenzirano
Is ‘Europeanization’ as disappointing a term as it is fashionable? Should it be abandoned, or is it useful for understanding European transformations? Five uses are discussed and it is argued that ...research need not be hampered by competing definitions as long as their meaning, the phenomena in focus, the simplifying assumption used, the models of change and the theoretical challenges involved, are clarified and kept separate. The research challenge is one of model building, not one of inventing definitions. While it is premature to abandon the term, its usefulness may be more limited than its widespread use could indicate. Europeanization may be less useful as an explanatory concept than as an attention–directing device and a starting point for further exploration.
Sample preparation for high-throughput sequencing (HTS) includes treatment with various laboratory components, potentially carrying viral nucleic acids, the extent of which has not been thoroughly ...investigated. Our aim was to systematically examine a diverse repertoire of laboratory components used to prepare samples for HTS in order to identify contaminating viral sequences.
A total of 322 samples of mainly human origin were analysed using eight protocols, applying a wide variety of laboratory components. Several samples (60% of human specimens) were processed using different protocols. In total, 712 sequencing libraries were investigated for viral sequence contamination.
Among sequences showing similarity to viruses, 493 were significantly associated with the use of laboratory components. Each of these viral sequences had sporadic appearance, only being identified in a subset of the samples treated with the linked laboratory component, and some were not identified in the non-template control samples. Remarkably, more than 65% of all viral sequences identified were within viral clusters linked to the use of laboratory components.
We show that high prevalence of contaminating viral sequences can be expected in HTS-based virome data and provide an extensive list of novel contaminating viral sequences that can be used for evaluation of viral findings in future virome and metagenome studies. Moreover, we show that detection can be problematic due to stochastic appearance and limited non-template controls. Although the exact origin of these viral sequences requires further research, our results support laboratory-component-linked viral sequence contamination of both biological and synthetic origin.
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Application of an in situ generated bulky palladium(II) hydride catalyst obtained from a 1:1:1 mixture of Pd(dba)2, P(tBu)3, and isobutyryl chloride provides an efficient protocol for the ...isomerization and migration of a variety of olefins. In addition to the isomerization of (Z)- to (E)-olefins, the conjugative migration of allylbenzenes, allyl ethers, and amines was effectively achieved in near-quantitative yields and with excellent functional group tolerance. Catalyst loadings in the range of 0.5−1.0 mol % were typically applied, but even loadings as low as 0.25 mol % could be achieved when the reactions were performed under neat conditions. More interestingly, the investigated catalyst proved to be selective for converting terminal alkenes to 2-alkenes. This one-carbon migration process for monosubstituted olefins provides an alternative catalyst, which bridges the gap between the allylation and propenylation/vinylation protocols. Several substrates, including homoallylic alcohols and amines, were selectively transformed into their corresponding 2-alkenes, and examples using enantiomerically enriched substrates provided products without epimerization at the allylic stereogenic carbon centers. Finally, some mechanistic investigations were undertaken to understand the nature of the active in situ generated Pd−H catalyst. These studies revealed that the catalytic system is highly dependent on the large steric demand of the P(tBu)3 ligand. The use of an alternative ligand, cataCXium PinCy, also proved effective for generating an active catalyst, and it was demonstrated in some cases to display better selectivity for the one-carbon shifts of terminal olefins. A possible intermediate involved in the preparation of the active catalyst was characterized by its single-crystal X-ray structure, which revealed a monomeric tricoordinated palladium(II) acyl complex, bearing a chloride ligand.
Shiga toxin 2 (Stx2) from Shiga toxin-producing Escherichia coli (STEC) was subtyped by a method involving partial sequencing of the stxAB₂ operon. Of 255 strains from the Danish STEC cohort, all 20 ...cases of hemolytic-uremic syndrome were associated with subtype Stx2 (11 cases), subtype Stx2c (1 case), or the two combined (8 cases).
The mechanism for the iridium–BINAP catalyzed dehydrogenative decarbonylation of primary alcohols with the liberation of molecular hydrogen and carbon monoxide was studied experimentally and ...computationally. The reaction takes place by tandem catalysis through two catalytic cycles involving dehydrogenation of the alcohol and decarbonylation of the resulting aldehyde. The square planar complex IrCl(CO)(rac-BINAP) was isolated from the reaction between Ir(cod)Cl2, rac-BINAP, and benzyl alcohol. The complex was catalytically active and applied in the study of the individual steps in the catalytic cycles. One carbon monoxide ligand was shown to remain coordinated to iridium throughout the reaction, and release of carbon monoxide was suggested to occur from a dicarbonyl complex. IrH2Cl(CO)(rac-BINAP) was also synthesized and detected in the dehydrogenation of benzyl alcohol. In the same experiment, IrHCl2(CO)(rac-BINAP) was detected from the release of HCl in the dehydrogenation and subsequent reaction with IrCl(CO)(rac-BINAP). This indicated a substitution of chloride with the alcohol to form a square planar iridium alkoxo complex that could undergo a β-hydride elimination. A KIE of 1.0 was determined for the decarbonylation and 1.42 for the overall reaction. Electron rich benzyl alcohols were converted faster than electron poor alcohols, but no electronic effect was found when comparing aldehydes of different electronic character. The lack of electronic and kinetic isotope effects implies a rate-determining phosphine dissociation for the decarbonylation of aldehydes.
The Sabatier principle states that optimal catalysis occurs when interactions between catalyst and substrate are of intermediary strength. Although qualitative in nature, this concept has proven ...extremely useful within (nonbiochemical) heterogeneous catalysis. In the current work, we show that the principle may be applied to an interfacial enzyme reaction. Specifically, we studied the breakdown of cellulose by different cellulases (wild types and variants) and found that the results could be rationalized in so-called volcano plots that are emblematic of the principle. This implies that the rate of the complex enzymatic reaction can be described by a single parameter (binding strength), and we show how this may help elucidating e.g. rate-controlling steps and relationships of substrate load and enzymatic efficacy. On a more general level, we propose that the Sabatier principle may be widely applicable to interfacial enzyme processes and hence open an avenue to the application within biocatalysis of some of the principles and practices originally developed for heterogeneous catalysis.
By using mechanistic insight, a new ligand (EPhos) for the palladium‐catalyzed C−N cross‐coupling between primary amines and aryl halides has been developed. Employing an isopropoxy group at the ...C3‐position favors the C‐bound isomer of the ligand‐supported palladium(II) complexes and leads to significantly improved reactivity. The use of a catalyst system based on EPhos with NaOPh as a mild homogeneous base proved to be very effective in the formation of 4‐arylaminothiazoles and highly functionalized 2‐arylaminooxazoles. Previously, these were not readily accessible using palladium catalysis.
Cross‐examination: A new ligand, EPhos, for palladium‐catalyzed C−N cross‐couplings has been developed based on a structure–activity relationship of BrettPhos‐related ligands. EPhos was successfully applied in the Pd‐catalyzed formation of 2‐(hetero)arylaminooxazoles and 4‐(hetero)arylaminothiazoles, the synthesis of which had previously proven problematic in transition‐metal catalysis.
This article questions the fashionable ideas that bureaucratic organization is an obsolescent, undesirable, and non-viable form of administration and that there is an inevitable and irreversible ...paradigmatic shift towards market- or network-organization. In contrast, the paper argues that contemporary democracies are involved in another round in a perennial debate and ideological struggle over what are desirable forms of administration and government: that is, a struggle over institutional identities and institutional balances. The argument is not that bureaucratic organization is a panacea and the answer to all challenges of public administration. Rather, bureaucratic organization is part of a repertoire of overlapping, supplementary, and competing forms coexisting in contemporary democracies, and so are market-organization and network-organization. Rediscovering Weber's analysis of bureaucratic organization, then, enriches our understanding of public administration. This is in particular true when we (a) include bureaucracy as an institution, not only an instrument; (b) look at the empirical studies in their time and context, not only at Weber's ideal-types and predictions; and (c) take into account the political and normative order bureaucracy is part of, not only the internal characteristics of “the bureau.”
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