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This study aimed at identifying the clinical characteristics and in-hospital outcomes of patients treated with polytetrafluorethylene (PTFE)-covered stents after coronary interventions in a multicenter registry. Subjects with coronary artery perforation were selected from 31,262 consecutive patients who underwent coronary interventions in the hospital registries. Subjects were divided into two groups: those with a PTFE-covered stent implantation and those without a PTFE-covered stent implantation. Clinical characteristics and in-hospital outcomes were compared between the two groups. Data for 82 consecutive coronary perforations (15 PTFE-covered stents and 67 non-PTFE-covered stents) were extracted from each hospital registry. The PTFE-covered stent group had a higher prevalence of perforations due to pre-dilatation before stenting or post-dilatation after stenting (80% vs. 10.4%; p < 0.001), more Ellis classification III perforations (66.6% vs. 28.4%; p = 0.019), longer perforation to hemostasis time (74 min vs. 10 min; p < 0.001), lower hemostatic success rates (73.3% vs. 94.0%; p = 0.015), and higher in-hospital mortality (26.7% vs. 6.0%; p = 0.015) than the non-PTFE-covered stent group. Although the prevalence of intravascular ultrasound (IVUS) usage was high during coronary interventions (86.7%), IVUS was performed in less than half the cases just before coronary perforations (47%) in the PTFE-covered stent group. Patients requiring PTFE-covered stents are more likely to be observed after balloon dilatation before or after stenting and have a poor prognosis. Careful coronary intervention is needed when IVUS image acquisition is not achieved in addition to proper evaluation of IVUS. Furthermore, if coronary artery perforation occurs, it is important to determine the need for a prompt PTFE-covered stent. [ABSTRACT FROM AUTHOR]

A method whereby several molecules can be arranged at one time onto spatially defined positions in the near-molecular scale, is reported. The approach is based on scanning probe lithography (SPL) with self-assembling of organosilane molecules. The SPL process was used to locally remove a trimethylsilyl ((CHsub3)sub3Si-), TMS monolayer on a silicon substrate.

Ionic liquids (ILs) have been intensively studied as one promising candidate for an electrolyte in lithium ion batteries (LIBs). Structural analysis of interfaces between an IL-based electrolyte and a LIB electrode would provide beneficial information for improving LIBs. In this study, we investigated the interfacial structures between an IL, 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide (EMI-TFSI), and a spinel-type lithium titanate (Li4Ti5O12) electrode in the presence and absence of Li-salt by frequency modulation atomic force microscopy (FM-AFM) utilizing a quartz tuning fork sensor. Solvation structures on the interface were successfully visualized by two-dimensional frequency shift mapping. Electrochemical impedance spectroscopy measurement was also performed to measure the rate of Li+-ion insertion/extraction on the interface and we found that the interfacial ion-transfer may prevent the formation of layered solvation structure. [ABSTRACT FROM AUTHOR]

Soaking of an irradiated sample in an aqueous solution of dye molecules facilitates the selective incorporation of dye molecules on the laser fabricated surface of poly(methyl methacrylate), with laser fluence controlling the selectivity. ESR spectroscopic study identifies a metastable molecular species of a propagating radical in the irradiated sample and X-ray photoelectron spectroscopy reveals the presence of oxygen containing-compounds. Only cationic dye molecules are incorporated due to the interaction with polar chemical species on the fabricated surface.