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81.
Luigi Sciarra Paolo Golia Andrea Natalizia Ermenegildo De Ruvo Serena Dottori Antonio Scarà Alessio Borrelli Lucia De Luca Marco Rebecchi Alessandro Fagagnini Alberto Bandini Fabrizio Guarracini Marcello Galvani Leonardo Calò 《Journal of interventional cardiac electrophysiology》2014,39(3):193-200
Introduction
Catheter ablation (CA) is an established therapy for atrial fibrillation (AF). The SmartTouch catheter (STc) provides information about catheter tip to tissue contact force (CF). The Surround Flow catheter (SFc) provides a uniform cooling of the tip during ablation. We sought to analyze the impact of STc and SFc on CA of paroxysmal AF in terms of feasibility and acute efficacy.Methods and results
Sixty-three patients (mean age 57.6?±?9.8 years, 53 males) with paroxysmal AF underwent pulmonary veins (PVs) antral isolation, by using standard ThermoCool catheter (TCc) in 21, STc in 21, and SFc in 21. Total procedural, fluoroscopy, and radiofrequency (RF) delivery times; percentage of persistently deconnected PVs after 30 min; and percentage of isolated PVs at the end of the procedure were measured. The use of both STc and SFc obtained a reduction of fluoroscopy time (TCc 34?±?18 min, STc 20?±?10 min, p?<?0.001; SFc 21?±?13 min, p?=?0.02 vs TCc) and RF time (TCc 41?±?13 min, STc 30?±?14 min, p?=?0.013; SFc 30?±?9 min, p?<?0.01 vs TCc). The use of STc resulted in a reduction of procedural time (TCc 181?±?53 min, STc 140?±?53 min, p?<?0.001; SFc 170?±?51 min, p?=?NS vs TCc). The percentage of isolated PVs was comparable between groups (TCc 96 % vs STc 98 % vs SFc 96 %; p?=?NS). The percentage of deconnected PVs at 30 min was lower in TCc (89 %) than in STc (95 %) and in SFc (95 %) group (p?<?0.05).Conclusions
Both STc and SFc allowed a simplification of CA of paroxysmal AF. In addition, they reduced early PVs reconnection.Condensed abstract
Sixty-three patients with paroxysmal AF underwent ablation by standard ThermoCool, SmartTouch, or Surround Flow catheter. Both the SmartTouch and the Surround Flow significantly reduced radiofrequency and fluoroscopy times, as well as pulmonary veins reconnection rate at 30 min. Moreover, the SmartTouch reduced overall duration of the procedure. 相似文献82.
Alessio Giannelli Cinzia Cantacessi Patricia Graves Luke Becker Bronwyn Evelyn Campbell Filipe Dantas-Torres Domenico Otranto 《Parasitology research》2014,113(5):1989-1991
Onchocerca lupi is a neglected filarioid causing nodular lesions associated with acute or chronic ocular disease in dogs. Despite the recent appraisal of its zoonotic potential, human cases are increasingly reported in the Old and New Worlds. Therefore, the development of accurate tools for the rapid diagnosis of O. lupi infections in dogs is becoming a priority. In this study, we conducted a preliminary investigation aimed at evaluating the usefulness of a commercially available ELISA test for the detection of O. lupi antigens in canine sera. The potential use of this tool for larger epidemiological studies of canine onchocerciasis is discussed. 相似文献
83.
Kai Liu Dong Chen Alessio Marcozzi Lifei Zheng Juanjuan Su Diego Pesce Wojciech Zajaczkowski Anke Kolbe Wojciech Pisula Klaus Müllen Noel A. Clark Andreas Herrmann 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(52):18596-18600
Complexation of biomacromolecules (e.g., nucleic acids, proteins, or viruses) with surfactants containing flexible alkyl tails, followed by dehydration, is shown to be a simple generic method for the production of thermotropic liquid crystals. The anhydrous smectic phases that result exhibit biomacromolecular sublayers intercalated between aliphatic hydrocarbon sublayers at or near room temperature. Both this and low transition temperatures to other phases enable the study and application of thermotropic liquid crystal phase behavior without thermal degradation of the biomolecular components.Liquid crystals (LCs) play an important role in biology because their essential characteristic, the combination of order and mobility, is a basic requirement for self-organization and structure formation in living systems (1–3). Thus, it is not surprising that the study of LCs emerged as a scientific discipline in part from biology and from the study of myelin figures, lipids, and cell membranes (4). These and the LC phases formed from many other biomolecules, including nucleic acids (5, 6), proteins (7, 8), and viruses (9, 10), are classified as lyotropic, the general term applied to LC structures formed in water and stabilized by the distinctly biological theme of amphiphilic partitioning of hydrophilic and hydrophobic molecular components into separate domains. However, the principal thrust and achievement of the study of LCs has been in the science and application of thermotropic materials, structures, and phases in which molecules that are only weakly amphiphilic exhibit LC ordering by virtue of their steric molecular shape, flexibility, and/or weak intermolecular interactions [e.g., van der Waals and dipolar forces (11)]. These characteristics enable thermotropic LCs (TLCs) to adopt a wide variety of exotic phases and to exhibit dramatic and useful responses to external forces, including, for example, the electro-optic effects that have led to LC displays and the portable computing revolution. This general distinction between lyotropic LCs and TLCs suggests there may be interesting possibilities in the development of biomolecular or bioinspired LC systems in which the importance of amphiphilicity is reduced and the LC phases obtained are more thermotropic in nature. Such biological TLC materials are very appealing for several reasons. Most biomacromolecules were extensively characterized in aqueous environments, but in TLC phases, their solvent-free properties and functions could be investigated in a state in which no or only traces of water are present. Water exhibits a high dielectric constant and has the ability to form hydrogen bonds, greatly influencing the structure and functions of biomacromolecules or compromising electronic properties such as charge transport (12–15). Indeed, anhydrous TLC systems containing glycolipids (16–19), ferritin (20), and polylysine have been reported (21–23). However, a general approach to fabricating TLCs based on nucleic acids, polypeptides, proteins, and protein assemblies of large molecular weights such as virus particles remains elusive.Here we propose that the combination of biomaterials with suitably chosen surfactants, followed by dehydration, can be effectively applied as a simple generic scheme for producing biomacromolecular-based TLCs. We demonstrate that biological TLCs can be made from a remarkable range of biomolecules and bio-inspired molecules, including nucleic acids, polypeptides, fusion proteins, and viruses. TLC materials typically combine rigid or semirigid anisometric units, which introduce orientational anisotropy, with flexible alkyl chains, which suppress crystallization (24). In the present experiments, negatively charged biomolecules and bio-inspired molecules act as rigid parts, and cationic surfactants make up the flexible units to produce TLC phases with remarkably low LC-isotropic clearing temperatures, which is another TLC signature. Electrostatic interactions couple these rigid and flexible components into hybrid assemblies, which then order into lamellar phases of alternating rigid and flexible layers (Fig. 1) stabilized by the tendency in TLCs for rigid and flexible to spatially segregate (25).Open in a separate windowFig. 1.Proposed structures of TLCs formed by the biological building blocks complexed with surfactants, showing sketches of various lamellar phases and the corresponding phase transition temperatures (°C). The lamellar bilayer structures are made of, alternately, a sublayer of the biomacromolecules and an interdigitated sublayer of the surfactants, where the negatively charged parts of the biomolecules (e.g., phosphate groups of ssDNA and ssRNA, glutamate residues of supercharged ELPs, and N-terminal glutamate and aspartate residues of pVIII protein in phages) electrostatically interact with the cationic head groups of the surfactants. For the ssDNA–DOAB and ssRNA–DOAB smectic TLCs, the oligonucleotides are randomly orientated in the DNA (RNA) sublayers. For the ELP–DDAB complexes, in addition to the bilayer smectic phase, a modulated smectic (Smmod) phase is observed at lower temperature. For the phage–DOAB–DDAB lamellar structures, rodlike virus particles are embedded in a sublayer between interdigitated surfactants with additional in-plane orientational order. 相似文献
84.
85.
Enrico Poletti Lorenzo Azzalini Mohamed Ayoub Soledad Ojeda Carlo Zivelonghi Alessio La Manna Barbara Bellini Adrin Lostalo Aurora Luque Giuseppe Venuti Matteo Montorfano Pierfrancesco Agostoni Manuel Pan Mauro Carlino Kambis Mashayekhi 《Catheterization and cardiovascular interventions》2020,96(1):E45-E52
86.
Fabbri M Paone A Calore F Galli R Gaudio E Santhanam R Lovat F Fadda P Mao C Nuovo GJ Zanesi N Crawford M Ozer GH Wernicke D Alder H Caligiuri MA Nana-Sinkam P Perrotti D Croce CM 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(31):E2110-E2116
MicroRNAs (miRNAs) are small noncoding RNAs, 19-24 nucleotides in length, that regulate gene expression and are expressed aberrantly in most types of cancer. MiRNAs also have been detected in the blood of cancer patients and can serve as circulating biomarkers. It has been shown that secreted miRNAs within exosomes can be transferred from cell to cell and can regulate gene expression in the receiving cells by canonical binding to their target messenger RNAs. Here we show that tumor-secreted miR-21 and miR-29a also can function by another mechanism, by binding as ligands to receptors of the Toll-like receptor (TLR) family, murine TLR7 and human TLR8, in immune cells, triggering a TLR-mediated prometastatic inflammatory response that ultimately may lead to tumor growth and metastasis. Thus, by acting as paracrine agonists of TLRs, secreted miRNAs are key regulators of the tumor microenvironment. This mechanism of action of miRNAs is implicated in tumor-immune system communication and is important in tumor growth and spread, thus representing a possible target for cancer treatment. 相似文献
87.
A Capotondo R Milazzo LS Politi A Quattrini A Palini T Plati S Merella A Nonis C di Serio E Montini L Naldini A Biffi 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(37):15018-15023
The recent hypothesis that postnatal microglia are maintained independently of circulating monocytes by local precursors that colonize the brain before birth has relevant implications for the treatment of various neurological diseases, including lysosomal storage disorders (LSDs), for which hematopoietic cell transplantation (HCT) is applied to repopulate the recipient myeloid compartment, including microglia, with cells expressing the defective functional hydrolase. By studying wild-type and LSD mice at diverse time-points after HCT, we showed the occurrence of a short-term wave of brain infiltration by a fraction of the transplanted hematopoietic progenitors, independently from the administration of a preparatory regimen and from the presence of a disease state in the brain. However, only the use of a conditioning regimen capable of ablating functionally defined brain-resident myeloid precursors allowed turnover of microglia with the donor, mediated by local proliferation of early immigrants rather than entrance of mature cells from the circulation. 相似文献
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