bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chronic total occlusions: Successful recanalization of very old lesions
Authors: Murarka Shishir , Heuser Richard R. 
Published: June 2012

PurposeThe treatment of chronic total occlusion is thought to be the final frontier in treating coronary artery disease nonsurgically. In the past, an old occlusion was not likely to be treated successfully percutaneous. We have had success in revascularizing some very old 20 plus year old occlusions percutaneously.MethodsSix patients were treated who had >20‐year‐old occlusions. Five patients were male; mean age of patients was 72.2 years (range 63–86). Mean age of the occlusion was 24.8 years. All patients had ischemia in the corresponding territory. Four of the patients had right coronary artery occlusions; one had a left circumflex occlusion and one had left anterior descending artery occlusion.ResultsUsing a combination of radial and/or femoral approach, we successfully recanalized all of these old occlusions. No patients had major adverse cardiac events. Two patients developed restenosis at follow‐up that was subsequently treated uneventfully. All the patients had a complete relief of angina.ConclusionIn a small single center experience, even very old occlusions >20‐year old can be effectively treated with dedicated systems, excellent guiding catheter support and experienced physicians. © 2012 Wiley Periodicals, Inc.
Prognostic value of creatine kinase‐myocardial band isoenzyme elevation following percutaneous coronary intervention: A meta‐analysis
Authors: Jang Jae‐Sik , Jin Han‐Young , Seo Jeong‐Sook , Yang Tae‐Hyun , Kim Dae‐Kyeong , Kim Dong‐Soo , Cho Kyoung‐Im , Kim Bo‐Hyun , Je Hyung‐Gon , Park Yong Hyun 
Published: June 2012

ObjectivesTo assess whether different degrees of creatine kinase‐myocardial band isoenzyme (CK‐MB) elevation after percutaneous coronary intervention (PCI) affect the subsequent risk of death.BackgroundWhile there is consensus that extensive cardiac enzyme elevation increase mortality significantly, there is uncertainty about the exact clinical impact of smaller CK‐MB elevations after PCI.MethodsThe published literature was scanned by formal searches of electronic databases such as PubMed and MEDLINE from January 1999 to October 2011. Risk ratio (RR) was used as summary estimate.ResultsTen studies have been included totaling 48,022 patients who underwent PCI (12,246 patients with CK‐MB elevation and 35,776 patients without CK‐MB elevation). Mean followup duration for each study ranged from 6 to 48 months. CK‐MB elevation >1× the upper limit of normal (ULN) conferred a significant increase in the risk of mortality with an overall RR of 1.74 (95% confidence interval [CI], 1.42 to 2.13, P < 0.001). Compared with patients without CK‐MB elevation, there was a dose‐response relationship with RR for death being 1.48 (95% CI, 1.25–1.77, P < 0.001) with CK‐MB elevation 1 to <3× ULN, 1.71 (95% CI, 1.23–2.37, P = 0.001) with CK‐MB elevation 3 to 5× ULN, and 2.83 (95% CI, 1.98–4.04, P < 0.001) with CK‐MB elevation ≥ 5× ULN.ConclusionsEven a small increase in CK‐MB levels after PCI is associated with significantly higher risk of late mortality. Monitoring cardiac enzymes after PCI may help predict the long term clinical outcome. © 2012 Wiley Periodicals, Inc.
First‐in‐man transfemoral transcatheter aortic valve replacement with the 29 mm Edwards SAPIEN XT Valve
Authors: Freeman Melanie , Rodés‐Cabau Josep , Urena Marina , DeLarochelliere Robert , Dumont Eric , Masson Jean‐Bernard , Willson Alexander B. , Binder Ronald K. , Toggweiler Stefan , Leipsic Jonathon , Wood David A. , Webb John G. 
Published: June 2012

ObjectivesTo demonstrate the feasibility of transfemoral transcatheter aortic valve replacement (TAVR) with the 29 mm Edwards SAPIEN XT valve and Novaflex™ + delivery system through a 20F expandable sheath (eSheath™, Edwards Lifesciences, USA). In addition, to describe the use of the Novaflex + delivery system and expandable sheath.BackgroundTAVR has undergone significant advances in device technology resulting in smaller profile sheaths and delivery systems, allowing transfemoral delivery of a 29 mm valve.MethodsTwelve patients underwent transfemoral TAVR with the 29 mm Edwards SAPIEN XT valve and Novaflex + delivery system through a 20F expandable sheath. Baseline clinical and procedural characteristics are evaluated. In‐hospital and 30‐day outcomes are reported according to Valve Academic Research Consortium criteria.ResultsAll patients were male with a mean aortic annulus diameter of 25.0 ± 1.1 mm and 25.9 ± 1.2 mm, on transesophageal echocardiography and multidetector computerized tomography, respectively. Mean iliofemoral minimal luminal diameter (MLD) was 8.0 ± 0.8 mm. Successful deployment of the valve occurred in 11 out of 12 patients. Valve embolization occurred in one patient. Aortic valve area increased from 0.7 ± 0.2 to 2.0 ± 0.5 cm2 (P < 0.001). There were two major vascular complications; however, there were no in‐hospital or 30‐day neurological events, need for pacemaker insertion, or mortality.ConclusionsTransfemoral TAVR with the 29 mm Edwards SAPIEN XT valve and Novaflex + delivery system through a 20F expandable sheath was feasible with acceptable short‐term outcomes. © 2012 Wiley Periodicals, Inc.
Ambulatory transradial percutaneous coronary intervention: A safe, effective, and cost‐saving strategy
Authors: Le Corvoisier Philippe , Gellen Barnabas , Lesault Pierre‐François , Cohen Remy , Champagne Stéphane , Duval Anne‐Marie , Montalescot Gilles , Elhadad Simon , Montagne Olivier , Durand‐Zaleski Isabelle , Dubois‐Randé Jean‐Luc , Teiger Emmanuel 
Published: June 2012

AbstractObjectives: The aim of this prospective, multicenter study was to assess the safety, feasibility, acceptance, and cost of ambulatory transradial percutaneous coronary intervention (PCI) under the conditions of everyday practice. Background: Major advances in PCI techniques have considerably reduced the incidence of post‐procedure complications. However, overnight admission still constitutes the standard of care in most interventional cardiology centers. Methods: Eligibility for ambulatory management was assessed in 370 patients with stable angina referred to three high‐volume angioplasty centers. On the basis of pre‐specified clinical and PCI‐linked criteria, 220 patients were selected for ambulatory PCI. Results: The study population included a substantial proportion of patients with complex procedures: 115 (52.3%) patients with multivessel coronary artery disease, 50 (22.7%) patients with multilesion procedures, and 60 (21.5%) bifurcation lesions. After 4‐6 hr observation period, 213 of the 220 patients (96.8%) were cleared for discharge. The remaining seven (3.2%) patients were kept overnight for unstable angina (n = 1), atypical chest discomfort (n = 2), puncture site hematoma (n = 1), or non‐cardiovascular reasons (n = 3). Within 24 hr after discharge, no patients experienced readmission, stent occlusion, recurrent ischemia, or local complications. Furthermore, 99% of patients were satisfied with ambulatory management and 85% reported no anxiety. The average non‐procedural cost was lower for ambulatory PCI than conventional PCI (1,230 ± 98 Euros vs. 2,304 ± 1814 Euros, P < 10−6). Conclusions: Ambulatory PCI in patients with stable coronary artery disease is safe, effective, and well accepted by the patients. It may both significantly reduce costs and optimize hospital resource utilization. © 2012 Wiley Periodicals, Inc.
Analysis of Why Boron Avoids sp2 Hybridization and Classical Structures in the BnHn+2 Series
Authors: Osorio Edison , Olson Jared K. , Tiznado William , Boldyrev Alexander I. 
Published: June 2012

AbstractWe performed global minimum searches for the BnHn+2 (n=2‐5) series and found that classical structures composed of 2c–2e BH and BB bonds become progressively less stable along the series. Relative energies increase from 2.9 kcal mol−1 in B2H4 to 62.3 kcal mol−1 in B5H7. We believe this occurs because boron atoms in the studied molecules are trying to avoid sp2 hybridization and trigonal structure at the boron atoms, as in that case one 2p‐AO is empty, which is highly unfavorable. This affinity of boron to have some electron density on all 2p‐AOs and avoiding having one 2p‐AO empty is a main reason why classical structures are not the most stable configurations and why multicenter bonding is so important for the studied boron–hydride clusters as well as for pure boron clusters and boron compounds in general.
Synthesis of Multifunctional Ag@Au@Phenol Formaldehyde Resin Particles Loaded with Folic Acids for Photothermal Therapy
Authors: Yang Ping , Xu Qi‐Zhi , Jin Sheng‐Yu , Lu Yang , Zhao Yang , Yu Shu‐Hong 
Published: June 2012

AbstractMultifunctional Ag@Au@ phenol formaldehyde resin (PFR) particles loaded with folic acids (FA) have been designed for killing tumor cells through photothermy conversion under the irradiation of near‐infrared (NIR) light. Possessing the virtue of good fluorescence, low toxicity, and good targeting, the nanocomposite consists of an Ag core, an Au layer, a PFR shell, and folic acids on the PFR shell. The Ag@PFR core–shell structure can be prepared with a simple hydrothermal method after preheating. We then filled the PFR shell with a layer of Au by heating and modified the shell with polyelectrolyte to change its surface charge state. To capture tumor cells actively, FA molecules were attached onto the surface of the Ag@Au@PFR particles in the presence of 1‐ethyl‐3‐(3‐dimethly aminopropyl) carbodiimide (EDAC) and N‐hydroxysuccinimide (NHS). Owing to the excellent property of Au NPs and Ag NPs as photothermal conversion agents, the Ag@Au@ PFR@FA particles can be utilized to kill tumor cells when exposed to NIR light.
Diagnosekompetenz durch informelle Lernarrangements?
Authors: Groß Katharina , Reiners Christiane S. 
Published: June 2012

AbstractDie Fähigkeit von Lehrerinnen und Lehrern zu einer angemessenen Diagnose stellt einen bedeutenden Aspekt der Lehrerkompetenz dar. Um diese zu entwickeln, bietet sich nicht nur der Weg über die Ermittlung von Lernvoraussetzungen der Schüler an, sondern auch ein Weg über die Lernschwierigkeiten an. Eine besondere (Teilnehmer‐)Gruppe stellt der 1999 vom Kölner Modell ins Leben gerufene Experimentalwettbewerb Chemie entdecken dar, der für Schüler der Sekundarstufe I in Nordrhein‐Westfalen konzipiert wurde. Bis heute verzeichnet der Wettbewerb insgesamt über 80 000 Teilnehmer von Gymnasien, Gesamt‐, Real‐ und Hauptschulen. Allerdings zeigt ein Blick in die Statistik, dass die Hauptschulen mit nur etwa 1 % und die Gesamtschulen mit nur 6 % der Gesamtteilnehmerzahl unterrepräsentiert sind. Der vorliegende Beitrag stellt eine Untersuchung vor, in der (Lern‐)Schwierigkeiten von Schülern, die zu einer Nicht‐Teilnahme an dem Experimentalwettbewerb führen, explorativ erhoben wurden.
Im Folgenden wird aus rein pragmatischen Gründen der Lesbarkeit für Lehrerinnen und Lehrer die männliche Sprachform „Lehrer“ und für Schülerinnen und Schüler die männliche Sprachform „Schüler“ verwendet.
„Wie ein Forscher sein“
Authors: Sommer Katrin , Kakoschke Annette , Schindler Simone , Buchwald Mara , Russek Adrian , Schäfer Alexander , Steff Henning , Krupp Ute 
Published: June 2012

Abstract„Forscherwelt“ ist eine von Henkel ins Leben gerufene Bildungsinitiative, die besonders Kinder im Grundschulalter für Naturwissenschaften begeistern will. In dem außerschulischen Lernort am Henkel‐Standort Düsseldorf experimentieren die Kinder zu Themen wie Kleben, Waschen oder Körperpflege und gewinnen – unterstützt von den Experten vor Ort – einen authentischen Einblick in das echte Forschungsgeschehen. Wissenschaftliche Grundlage des didaktischen Konzeptes der Forscherwelt bildet das Konstrukt der naturwissenschaftlichen Grundbildung. Dabei zielt das didaktische Konzept auf folgende Elemente eines naturwissenschaftlichen Forschungsprozesses ab: Wissenschaftliche Methoden und kritisches Nachprüfen, Analyse und Interpretation von Daten, Wissenschaft und Fragen sowie Kreativität. Das Beispiel des fünftägigen Ferienkurses zum Thema Kleben zeigt, wie die Merkmale des didaktischen Konzeptes die Gestaltung der einzelnen Projekttage prägen.
The role of clinicians in determining radioactive iodine use for low‐risk thyroid cancer
Authors: Haymart Megan R. , Banerjee Mousumi , Yang Di , Stewart Andrew K. , Koenig Ronald J. , Griggs Jennifer J. 
Published: June 2012

AbstractBACKGROUND:There is controversy regarding the optimal management of thyroid cancer. The proportion of patients with low‐risk thyroid cancer who received radioactive iodine (RAI) treatment increased over the last 20 years, and little is known about the role played by clinicians in hospital‐level RAI use for low‐risk disease.METHODS:Thyroid surgeons affiliated with 368 hospitals that had Commission on Cancer‐accredited cancer programs were surveyed. Survey data were linked to data reported to the National Cancer Database. A multivariable analysis was used to assess the relation between clinician decision makers and hospital‐level RAI use after total thyroidectomy in patients with stage I, well differentiated thyroid cancer.RESULTS:The survey response rate was 70% (560 of 804 surgeons). The surgeon was identified as the primary decision maker by 16% of the surgeons; the endocrinologist was identified as the primary decision maker by 69%, and a nuclear medicine, radiologist, or other physician was identified as the primary decision maker by 15%. In a multivariable analysis controlling for hospital case volume and hospital type, when the primary decision maker was in a specialty other than endocrinology or surgery, there was greater use of RAI at the hospital (P < .001). A greater number of providers at the hospital where RAI was administered and having access to a tumor board also were associated with increased use of RAI (P < .001 and P = .006, respectively).CONCLUSIONS:The specialty of the primary decision maker, the number of providers administering RAI, and having access to a tumor board were associated significantly with the use of RAI for stage I thyroid cancer. The findings have implications for addressing nonclinical variation between hospitals, with a marked heterogeneity in decision making suggesting that standardization of care will be challenging. Cancer 2013. © 2012 American Cancer Society.
A DOF‐based dynamic spectrum auction algorithm in cognitive femtocell
Authors: Wu Guangen , Ren Pinyi , Du Qinghe , Zhang Chao 
Published: June 2012

SUMMARYDynamic spectrum auction (DSA) has been considered as one of potential spectrum allocation approaches in cognitive femtocell networks. As a modified version of traditional spectrum auction, DSA should not only increase auction revenue but also improve spectrum utilization on finer time granularity. We propose a DSA algorithm based on a double optimization framework (DOF), which focuses on the optimization of auction revenue and spectrum utilization. The optimization processing consists of two stages. Firstly, a proper auction period is selected to balance the expected spectrum utilization and auction revenue. Then, the cognitive femtocell base station adjusts its reserve price with the repetition of auction to leverage over instant revenue and spectrum utilization. At the same time, the bidders can adjust their bidding price to improve utilities. Performance analysis shows that the DOF‐based DSA algorithm has low complexity and can resist collusion, so it can be carried out frequently with small overhead. On the other hand, it is better than the greedy algorithm and Vickrey–Clarke–Groves auction on revenue. Simulation results show that the DOF‐based DSA algorithm can keep a fine spectrum utilization and bring the cognitive femtocell base station more revenue in both single‐unit award spectrum auction and multi‐unit awards spectrum auction. Copyright © 2012 John Wiley & Sons, Ltd.
Spectroscopic Investigation into Oxidative Degradation of Silica‐Supported Amine Sorbents for CO2 Capture
Authors: Srikanth Chakravartula S. , Chuang Steven S. C. 
Published: June 2012

AbstractOxidative degradation characteristics of silica‐supported amine sorbents with varying amounts of tetraethylenepentamine (TEPA) and polyethylene glycol (PEG; P200 or P600 represents PEG with molecular weights of 200 or 600) have been studied by IR and NMR spectroscopy. Thermal treatment of the sorbents and liquid TEPA at 100 °C for 12 h changed their color from white to yellow. The CO2 capture capacity of the TEPA/SiO2 sorbents (i.e., SiO2‐supported TEPA with a TEPA/SiO2 ratio of 25:75) decreased by more than 60 %. IR and NMR spectroscopy studies showed that the yellow color of the degraded sorbents resulted from the formation of imide species. The imide species, consisting of NH associated with two CO functional groups, were produced from the oxidation of methylene groups in TEPA. Imide species on the degraded sorbent are not capable of binding CO2 due to its weak basicity. The addition of P200 and P600 to the supported amine sorbents improved both their CO2 capture capacities and oxidative degradation resistance. IR spectroscopy results also showed that TEPA was immobilized on the SiO2 surface through hydrogen bonding between amine groups and the silanol groups of SiO2. The OH groups of PEG interact with NH2/NH of TEPA through hydrogen bonding. Hydrogen bonds disperse TEPA on SiO2 and block O2 from accessing TEPA for oxidation. Oxidative degradation resistance and CO2 capture capacity of the supported amine sorbents can be optimized through adjusting the ratio of hydroxyl to amine groups in the TEPA/PEG mixture.
Dynamics of GFRα1‐positive spermatogonia at the early stages of colonization in the recipient testes of W/Wν male mice
Authors: Nagai Ryohei , Shinomura Mai , Kishi Kasane , Aiyama Yoshimi , Harikae Kyoko , Sato Takeshi , Kanai‐Azuma Masami , Kurohmaru Masamichi , Tsunekawa Naoki , Kanai Yoshiakira 
Published: June 2012

AbstractBackground: The spermatogonial transplantation experiment can be used as an unequivocal detection assay of spermatogenic stem cells (SSCs) in both a qualitative and quantitative manner, based on their regenerative capacity. In this study, the proliferative patterns and kinetics of donor‐derived GFRα1‐positive spermatogonia containing potential SSCs were examined during early colonization following spermatogonial transplantation.Results: Donor‐derived GFRα1‐positive cells frequently formed several aggregates of Aal(aligned)/morula‐like structures in a single spermatogenic cell patch before and on day 14 post‐transplant, indicating a possible involvement in the formation of a stable spermatogenic colony at 21 days post‐transplant. The appearance of these Aal/morula‐like aggregates is positively correlated with regional, high‐level expression of immunoreactive GDNF signals, a ligand for GFRα1, associated with colony expansion. Conclusions: These data raise the hypothesis that regional GDNF signals regulate the balance between donor‐derived Aal‐like cell aggregates and their differentiation in each small patch, which subsequently leads to further selection of survival colonies at later stages. Developmental Dynamics 241:1374–1384, 2012. © 2012 Wiley Periodicals, Inc.
Longitudinal studies of cerebral glucose metabolism in late‐life depression and normal aging
Authors: Marano Christopher M. , Workman Clifford I. , Kramer Elisse , Hermann Carol R. , Ma Yilong , Dhawan Vijay , Chaly Thomas , Eidelberg David , Smith Gwenn S. 
Published: June 2012

ObjectiveLate‐life depression (LLD) has a substantial public health impact and is both a risk factor for and a prodrome of dementia. Positron emission tomography (PET) studies of cerebral glucose metabolism have demonstrated sensitivity in evaluating neural circuitry involved in depression, aging, incipient cognitive decline, and dementia. The present study evaluated the long term effects of a course of antidepressant treatment on glucose metabolism in LLD patients.MethodsNine LLD patients and seven non‐depressed control subjects underwent clinical and cognitive evaluations as well as brain magnetic resonance imaging and PET studies of cerebral glucose metabolism at baseline, after 8 weeks of treatment with citalopram for a major depressive episode (patients only), and at an approximately 2‐year follow‐up.ResultsThe majority of LLD patients were remitted at follow‐up (7/9). Neither patients nor controls showed significant cognitive decline. The patients showed greater increases in glucose metabolism than the controls in regions associated with mood symptoms (anterior cingulate and insula). Both groups showed decreases in metabolism in posterior association cortices implicated in dementia.ConclusionsLongitudinal changes in cerebral glucose metabolism are observed in controls and in LLD patients without significant cognitive decline that are more extensive than the decreases in brain volume. Longer duration follow‐up studies and the integration of other molecular imaging methods will have implications for understanding the clinical and neurobiological significance of these metabolic changes. Copyright © 2012 John Wiley & Sons, Ltd.
Alcohols Promoted Green Protocol for Biginelli Reaction
Authors: Imtiaz Shamila , Khan Misbahul Ain , Sharif Ahsan , Ahmed Ejaz , Lin Whei‐Oh , Munawar Munawar Ali 
Published: June 2012

AbstractA green chemistry protocol using ethylene glycol and diethylene glycol is developed for the synthesis of dihydropyrimidinones.
Theoretical Study on the Gas‐Phase SN2 Reaction of Microhydrated Fluoride with Methyl Fluoride
Authors: Chen Jien‐Lian , Hu Wei‐Ping 
Published: June 2012

AbstractThe rate constants for the gas‐phase SN2 reaction of F−(H2O) with CH3F have been calculated using the dual‐level variational transition state theory including multidimensional tunneling from 50 to 500 K. Tunneling was found to dominate the reaction below 200 K. The deuterium, 13C, and 14C kinetic isotope effects (KIEs) and solvent (D2O) isotope effects (SKIEs) were also calculated in the same temperature range. The results indicated that the deuterium and heavy water substitutions resulted in inverse KIEs (0.6∼0.8 ) while the 13C and 14C substitutions resulted in normal KIEs (1.0∼1.2) at room temperature. The calculated carbon KIEs increased significantly below 80 K due to the differences in the magnitude of the tunneling effects for different isotopic substitutions.