bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Strukturaufklärung und Totalsynthese von β‐Lipomycin
Authors: Hartmann Olaf , Kalesse Markus 
Published: May 2014

AbstractWir beschreiben hier die Synthese des aus Corallococcus coralloides isolierten Naturstoffs β‐Lipomycin. Die Konfiguration des Zielmoleküls wurde dabei mithilfe eines “Profile‐Hidden‐Markov”‐Modells bestimmt, da sich mit diesem statistischen Ansatz nicht nur die Konfigurationen von sekundären Alkoholen sondern auch die von α‐Methylgruppenverzweigungen vorhersagen lassen. Damit liefert die Synthese nicht nur einen praktikablen Zugang zu diesem Naturstoff, sondern bestätigt auch die Gültigkeit des hier verwendeten Modells zur Vorhersage der Konfiguration von α‐Methylgruppenverzweigungen in modularen Polyketiden.
Bildung von Superoxiden an isolierten kationischen Goldclustern
Authors: Woodham Alex P. , Fielicke André 
Published: May 2014

AbstractNanopartikel aus Gold katalysieren vielfältige Oxidationsreaktionen mit molekularem Sauerstoff, allerdings sind die Reaktionsmechanismen und die für Aktivierung des Sauerstoffs verantwortlichen Spezies unklar. Wir untersuchten die Reaktion zwischen freien kationischen Goldclustern und molekularem Sauerstoff. Die gebildeten Komplexe wurden in der Gasphase mittels Infrarotspektroskopie charakterisiert. Eine starke Rotverschiebung der beobachteten ν(O‐O)‐Streckfrequenz verweist auf die Bildung von Superoxo(O2−)‐Einheiten. Diese bilden sich spontan in Systemen, die durch den Elektronentransfer eine geschlossene Schale innerhalb des sphärischen Jellium‐Modells ausbilden (Au10+ und Au22+). Für andere Cluster (Au4+, Au12+, Au21+) wird die Aktivierung erst nach der Bindung weiterer Sauerstoffmoleküle beobachtet.
Direct Electrochemical Capture and Release of Carbon Dioxide Using an Industrial Organic Pigment: Quinacridone
Authors: Apaydin Dogukan Hazar , Głowacki Eric Daniel , Portenkirchner Engelbert , Sariciftci Niyazi Serdar 
Published: May 2014

AbstractLimiting anthropogenic carbon dioxide emissions constitutes a major issue faced by scientists today. Herein we report an efficient way of controlled capture and release of carbon dioxide using nature inspired, cheap, abundant and non‐toxic, industrial pigment namely, quinacridone. An electrochemically reduced electrode consisting of a quinacridone thin film (ca. 100 nm thick)on an ITO support forms a quinacridone carbonate salt. The captured CO2 can be released by electrochemical oxidation. The amount of captured CO2 was quantified by FT‐IR. The uptake value for electrochemical release process was 4.61 mmol g−1. This value is among the highest reported uptake efficiencies for electrochemical CO2 capture. For comparison, the state‐of‐the‐art aqueous amine industrial capture process has an uptake efficiency of ca. 8 mmol g−1.
Synthesis and fluorescence properties of 1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazol derivatives and their terbium complexes
Authors: Zhang Wu , Chai Yuchao , Li Kangyun , Chen Yanwen , Yan Dong , Guo Dongcai 
Published: May 2014

ABSTRACTEight novel 1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazol derivatives have been designed and synthesized, and their corresponding Tb3+ complexes were also prepared successfully. The fluorescence properties and fluorescence quantum yields of the target complexes were investigated, the results showed that the ligands were an efficient sensitizer for Tb3+ luminescence, and the target complexes exhibited characteristic fluorescence emissions of Tb3+ ion. The fluorescence intensity of the complex substituted by chlorine was stronger than that of other complexes. The substituents' nature has a great effect upon the electrochemical properties of the target complexes. The results showed that the introduction of the electron‐withdrawing groups tended to decrease the oxidation potential and highest occupied molecular orbital energy levels of the target Tb3+ complexes; however, introduction of the electron‐donating groups can increase the corresponding complexes' oxidation potential and highest occupied molecular orbital energy levels. Copyright © 2014 John Wiley & Sons, Ltd.
Statin use and rupture of abdominal aortic aneurysm
Authors: Wemmelund H , Høgh A , Hundborg H H , Thomsen R W , Johnsen S P , Lindholt J S 
Published: May 2014

Abstract

Background
Ruptured abdominal aortic aneurysm (rAAA) is associated with high mortality. Research suggests that statins may reduce abdominal aortic aneurysm (AAA) growth and improve rAAA outcomes. However, the clinical impact of statins remains uncertain in relation to both the risk and prognosis of rAAA.

Methods
This nationwide, population-based, combined case–control and follow-up study included all patients (aged at least 50 years) with a first-time hospital admission for rAAA and 1 : 1 matched AAA controls without rupture in Denmark from 1996 to 2008. Individual-level data on preadmission drug use, co-morbidities, socioeconomic markers, healthcare contacts and death were obtained from Danish nationwide registries.

Results
The study included 3584 cases and 3584 matched controls. Current statin use was registered for 418 patients with rAAA (11·7 per cent) and 539 AAA controls (15·0 per cent), corresponding to an age- and sex-matched odds ratio (OR) of 0·70 (95 per cent confidence interval (c.i.) 0·60 to 0·81) for rAAA in current statin users versus never users. The decreased risk of rAAA remained after adjustment for potential confounding factors (adjusted OR 0·73, 0·61 to 0·86). The overall 30-day mortality rate from time of hospital admission among patients with rAAA was 46·1 per cent in current statin users compared with 59·3 per cent in never users (adjusted mortality rate ratio (MRR) 0·80, 95 per cent c.i. 0·68 to 0·95). Patients who had formerly used statins did not have reduced mortality (adjusted MRR 0·98, 0·78 to 1·22).

Conclusion
Statin use was associated with a reduced risk of rAAA and lower case fatality following rAAA. These results support current guidelines that recommend statin therapy in patients diagnosed with AAA.
Populating semantic virtual environments
Authors: Pelkey Cameron D. , Allbeck Jan M. 
Published: May 2014

ABSTRACTThe capacity for knowledge representation within simulated environments is a growing field of research geared toward the inclusion of detailed descriptors within the environment through which to provide a virtual agent the knowledge necessary to afford decision‐making and interaction. One such layer of representation is that concerning the natural‐language, or semantic, depiction of the environment and the objects within it. However, even as technology grows more capable of representing such information‐rich environments, the process of authoring and injecting this knowledge has largely remained a manual effort. Not only is this effort arduous for the author in both time and energy expenditure required, but the process also lends itself to limiting the ontology of the simulation further constraining the extent to which such knowledge may be used. Here, we offer an affordable method for semi‐automating the generation and injection of semantic properties into a virtual environment for the purpose of producing more natural agent‐object interaction. Copyright © 2014 John Wiley & Sons, Ltd.
Palladium Nanoparticles Supported on Nitrogen‐Doped Carbon Nanofibers: Synthesis, Microstructure, Catalytic Properties, and Self‐Sustained Oscillation Phenomena in Carbon Monoxide Oxidation
Authors: Stonkus Olga A. , Kibis Lidiya S. , Yu. Podyacheva Olga , Slavinskaya Elena M. , Zaikovskii Vladimir I. , Hassan Abdelwahab H. , Hampel Silke , Leonhardt Albrecht , Ismagilov Zinfer R. , Noskov Aleksandr S. , Boronin Andrey I. 
Published: May 2014

AbstractThe oxidation of CO over Pd nanoparticles supported on carbon nanofibers (CNFs) and N‐doped carbon nanofibers (N‐CNFs) has been studied. Investigation by scanning transmission electron microscopy together with electron energy‐loss spectroscopy revealed that Pd nanoparticles are located on the N‐CNFs surface patches that have a high concentration of N atoms. The N‐doping of CNFs was shown to change the electric conductivity of N‐CNFs and redox properties of Pd, which thus determines the self‐oscillatory behavior of the catalysts during CO oxidation, the type of oscillations, and the conditions of their generation. Mechanisms that underlie the effect of N in N‐CNFs on the electronic state of Pd as well as the occurrence of two types of oscillation mechanisms—the known redox mechanism and the mechanism related to Pd intercalation into graphene layers—are discussed.
Membrane Fuel Cell Cathode Catalysts Based on Titanium Oxide Supported Platinum Nanoparticles
Authors: Gebauer Christian , Jusys Zenonas , Wassner Maximilian , Hüsing Nicola , Behm R. Jürgen 
Published: May 2014

AbstractThe potential of platinum catalysts supported on pure, nitrogen‐, or carbon‐doped titania for application in the oxygen reduction reaction (ORR), as a cathode catalyst in polymer electrolyte membrane fuel cells, is investigated. The oxide supports are synthesized by using a sol–gel route. Modification with nitrogen and carbon doping is achieved by thermal decomposition of urea and the structure‐directing agent P123. Platinum nanoparticles are prepared by reduction of a PtIV salt in ethylene glycol and subsequently immobilized on different support materials. Structural and electronic properties of the support materials and the resulting catalysts are characterized by various methods, including X‐ray diffraction, transmission electron microscopy, and X‐ray photoelectron spectroscopy. These results and electrochemical characterization of the support materials and platinum nanoparticle catalysts indicate distinct support effects in the catalysts. The electrocatalytic performance of these catalysts in the ORR, as determined in rotating ring disc electrode measurements, is promising. Also here, distinct support effects can be identified. Correlations with the structural/electronic and the electrochemical properties are discussed, as well as the role of metal–support interactions.
Potential interactions between HIV drugs, ritonavir and efavirenz and anticancer drug, nilotinib—a study in primary cultures of human hepatocytes that is applicable to HIV patients with cancer
Authors: Pillai Venkateswaran C. , Parise Robert A. , Christner Susan M. , Rudek Michelle A. , Beumer Jan H. , Venkataramanan Raman 
Published: May 2014

AbstractNilotinib is used to treat chronic myeloid leukemia (CML), and is metabolized by CYP3A. With a black‐box warning for QT prolongation, which is exposure dependent, controlling for drug interactions is clinically relevant. Treatments of HIV patients with CML are with HAART drugs, ritonavir and efavirenz, may cause complex drug interactions through CYP3A inhibition or induction. We evaluated the interactions of ritonavir or efavirenz on nilotinib using human hepatocytes and compared these interactions with those of ketoconazole or rifampin, classical CYP3A inhibitor and inducer, respectively. Hepatocytes were treated with vehicle, ritonavir (10 μM), ketoconazole (10 μM), efavirenz (10 μM), or rifampin (10 μM) for 5 days. On day 5, nilotinib (3 μM) was coincubated for an additional 24–48 hours. The concentrations of nilotinib were quantitated in collected samples (combined lysate and medium) by LC‐MS. Apparent intrinsic clearance (CLint,app) of nilotinib was lowered 5.8‐ and 3.1‐fold, respectively, by ritonavir and ketoconazole. Efavirenz and rifampin increased the CLint,app of nilotinib by 2.1‐ and 4.1‐fold, respectively. The clinically recommended dose (300 mg twice daily) of nilotinib may have to be reduced substantially (150 mg once daily) or increased (400 mg thrice daily), respectively, to achieve desired drug exposure, when ritonavir or efavirenz is co‐administered.
Population pharmacokinetics of brodalumab in healthy adults and adults with psoriasis from single and multiple dose studies
Authors: Endres Christopher J. , Salinger David H. , Köck Kathleen , Gastonguay Marc R. , Martin David A. , Klekotka Paul , Nirula Ajay , Gibbs Megan A. 
Published: May 2014

AbstractBrodalumab, a human monoclonal IgG2‐antibody, acts as a potent antagonist at the interleukin‐17 receptor A, which is important in the pathogenesis of psoriasis. To characterize the pharmacokinetics of brodalumab and assess the effects of covariates, brodalumab concentrations from Phase 1a and Phase 2 clinical studies in healthy adults and subjects with psoriasis were used to construct a population PK model. The final two‐compartment model with parallel linear and non‐linear elimination pathways fit the data well. The population typical values for PK parameters CL, V, and Vmax were 0.223 L/day, 4.62 L, and 5.40 mg/day with between‐subject‐variability of 69.2, 69.6, and 25.9%CV, respectively. Body weight (BW) was an important covariate on CL (and Q), V (and V2) and Vmax, with estimated effect exponents of 0.598, 0.849, and 1.12, respectively. Based on simulations from the final model, for doses between 140 and 210 mg, AUC was predicted to be greater than two fold higher in subjects weighing less than 75 kg compared to reference subjects. Age and diagnosis had smaller influence on exposure and was not clinically significant. These data suggest that BW is an important covariate explaining some of the variability in population PK observed in human clinical trials with brodalumab.
Frequency of SPINK1 N34S mutation in acute and recurrent acute pancreatitis
Authors: Rai Praveer , Sharma Anjali , Gupta Ankur , Aggarwal Rakesh 
Published: May 2014

AbstractBackgroundSeveral studies have reported association of c.101A>G (p.N34S) mutation in SPINK1 gene with chronic pancreatitis; however, the data on its relationship with acute pancreatitis (AP) and recurrent acute pancreatitis (RAP) are limited.MethodsWe studied 183 unrelated patients with AP and RAP and 168 healthy controls for p.N34S variant in SPINK1 gene using sequencing of genomic DNA.ResultsSPINK1 p.N34S mutation was found in four of 168 (2.4%; all heterozygotes) controls and 22 of 183 (12.0%; including one homozygote) patients with AP (P = 0.006). On subgroup analysis, seven of 70 (10.0%) patients with gallstone‐related AP, eight of 59 (13.6%; including one homozygote) patients with idiopathic AP, and six of 44 (14.6%) patients with alcohol‐related AP had the p.N34S mutation (P = 0.027, 0.002 and 0.006, respectively, compared to controls). Frequency of this mutation was similar in patients with one episode of AP and those with recurrent AP (12% each). The first attack of AP occurred earlier in patients with p.N34S mutation than in those without it (mean ± SD age: 32.0 ± 9.7 versus 39.1 ± 13.4 years; P = 0.004). No patient had any other mutation in the exon 3 of the SPINK1 gene, whereas one control had a heterozygous p.P55S mutation.ConclusionsThe p.N34S mutation in SPINK1 gene was found more frequently in patients with AP in the Indian population, irrespective of disease etiology and whether the disease was recurrent or not, and was associated with disease onset at an earlier age. These findings suggest that p.N34S mutation lowers the threshold for occurrence of AP irrespective of the causative insult.
Molecular profiling in gastric cancer: Examining potential targets for chemotherapy
Authors: Miura John T. , Johnston Fabian M. , Thomas James , George Ben , Eastwood Dan , Tsai Susan , Christians Kathleen K. , Turaga Kiran K. , Gamblin T. Clark 
Published: May 2014

Background and ObjectivesCurrent NCCN guidelines recommend epirubicin (E), cisplatin (C), and 5‐fluorouracil (F) as a first‐line therapeutic approach for operable gastric adenocarcinoma (GC). Molecular profiling (MP) was used to evaluate the expression of chemotherapy targeted biomarkers associated with ECF therapy and other first‐line cytotoxic regimens for GC.MethodsGC specimens were analyzed by immunohistochemistry (IHC) for TOP2A, TS, ERCC1, PGP, and TOPO1 expression (Caris Life Sciences, Phoenix, AZ) from 2009 to 2012.ResultsA total of 230 GC specimens were analyzed. The median age of patients was 61 (IQR: 50–72) years with the majority being male (n = 139, 60%). IHC actionable targets included: 60% (n = 138) high TOP2A, 55% (n = 127) negative ERCC1, and 63% (n = 145) negative TS, indicating potential benefit from E, C, and F, respectively. Simultaneous expression analysis demonstrated only 24% (n = 55) of patients had gene expression levels that suggested uniform sensitivity to ECF. Biomarker results of 6.5% (n = 15) of patients revealed a potential complete lack of sensitivity to first‐line ECF.ConclusionsMP of GC has the potential to define patients who would derive the greatest benefit from current therapies. Prospective controlled studies are required to validate the role of biomarkers in the management of GC patients. J. Surg. Oncol. 2014 110:302–306. © 2014 Wiley Periodicals, Inc.
Formation of Isolated Titanium(III) Ions as Active Sites of Supported Titanium–Magnesium Catalysts for Polymerization of Olefins
Authors: Mikenas Tatiana B. , Koshevoy Evgeny I. , Zakharov Vladimir A. , Nikolaeva Marina I. 
Published: May 2014

Electron spin resonance (ESR) studies reveal a high yield of isolated Ti3+ compounds (30–70% of the total titanium content) that form in superactive supported titanium–magnesium catalysts (TMCs) of composition TiCl4/MgCl2 with a low titanium content (≤0.1 wt%) after their interaction with different aluminum trialkyls (AlR3). These catalysts strongly differ from conventional TMCs with titanium contents of 1–3 wt%, which produce a set of isolated or associated Ti(II) and Ti(III) species after the interaction with the AlR3. A correlation is found between the content of the isolated Ti(III) ions and the activity in ethylene polymerization. According to temperature rising elution fractionation (TREF) data, the catalysts with a low titanium content (isolated Ti(III) ions) mainly produce polypropylene with a very high atactic‐fraction content. Organic products formed on the interaction of AlEt3 and AlMe3 with TMC are identified. The data obtained allow a scheme of Ti3+ and Ti2+ compounds formed in these catalysts to be proposed.
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The effect of high flow nasal cannula therapy on the work of breathing in infants with bronchiolitis
Authors: Pham Trang M.T. , O'Malley Lee , Mayfield Sara , Martin Simon , Schibler Andreas 
Published: May 2014

SummaryThe main physiological impact of high flow nasal cannula (HFNC) therapy is presumed to be a decrease in work of breathing (WOB). To assess this, diaphragmatic electrical activity and esophageal pressure changes were measured off then on HFNC delivered at 2 L/kg/min, in 14 infants with bronchiolitis and 14 cardiac infants. Electrical activity of the diaphragm (Edi) was measured using an Edi catheter with calculations of signal peak (EdiMAX) and amplitude (EdiAMPL). Pressure–rate and pressure–time products (PRP, PTP) were calculated from analyses of esophageal pressure. Changes in end‐expiratory lung volume were measured using respiratory inductance plethysmography (RIPEEL). The EdiMAX and EdiAMPL were significantly higher in infants with bronchiolitis than in cardiac infants (P < 0.05). Within the bronchiolitis group, both were significantly reduced between HFNC states from 27.9 µV [20.4, 35.4] to 21.0 µV [14.8, 27.2] and from 25.1 µV [18.0, 32.2] to 19.2 µV [13.3, 25.1], respectively (mean, 95% CI, P < 0.05). A less prominent offload of the diaphragm was observed in cardiac infants (P < 0.05). WOB decreased in both groups with a significant reduction of PRP and PTP (P < 0.05). RIPEEL increased significantly in bronchiolitis only (P < 0.05). HFNC offloads the diaphragm and reduces the WOB in bronchiolitis. A similar effect was demonstrated in cardiac infants, a group without signs of airway‐obstruction. Pediatr Pulmonol. 2015; 50:713–720. © 2014 Wiley Periodicals, Inc.
Futility and the Care of Surgical Patients: Ethical Dilemmas
Authors: Grant Scott B. , Modi Parth K. , Singer Eric A. 
Published: May 2014

AbstractFutility has been a contentious topic in medicine for several decades. Surgery in critical or end‐of‐life situations often raises difficult questions about futility. In this article, we discuss the definition of futility, methods for resolving futility disputes, and some ways to reframe the futility debate to a more fruitful discussion about the goals of care, better communication between surgeon and patient/surrogate, and palliative surgical care. Many definitions of futile therapy have been discussed. The most controversial of these is “qualitative futility” which describes a situation in which the treatment provided is likely to result in an unacceptable quality of life. This is an area of continued controversy because it has been impossible to identify universally held beliefs about acceptable quality of life. Many authors have described methods for resolving futility disputes, including community standards and legalistic multi‐step due process protocols. Others, however, have abandoned the concept of futility altogether as an unhelpful term. Reframing the issue of futility as one of inadequate physician–patient communication, these authors have advocated for methods of improving communication and strengthening the patient–physician relationship. Finally, we discuss the utilization of consultants who may be of use in resolving futility disputes: ethics committees, palliative care specialists, pastoral care teams, and dedicated patient advocates. Involving these specialists in a futility conflict can help improve communication and provide invaluable assistance in arriving at the appropriate treatment decision.
Effective clearance of GL‐3 in a human iPSC‐derived cardiomyocyte model of Fabry disease
Authors: Itier Jean‐Michel , Ret Gwénaëlle , Viale Sandra , Sweet Lindsay , Bangari Dinesh , Caron Anne , Le‐Gall Françoise , Bénichou Bernard , Leonard John , Deleuze Jean‐François , Orsini Cécile 
Published: May 2014

AbstractFabry disease, a rare X‐linked α‐galactosidase A deficiency, causes progressive lysosomal accumulation of globotriaosylceramide (GL‐3) in a variety of cell types. As the disease progresses, renal failure, left ventricular hypertrophy, and strokes may occur. Enzyme replacement therapy (ERT), with recombinant α‐galactosidase A, is currently available for use to reduce GL‐3 deposits. However, although it improves cardiac function and decreases left ventricular mass, GL‐3 clearance upon ERT has been demonstrated in cardiac capillary endothelium but not in cardiomyocytes of patients. Relevant models are needed to understand the pathogenesis of cardiac disease and explore new therapeutic approaches. We generated induced pluripotent stem cells (iPSC) from Fabry patients and differentiated them into cardiomyocytes. In these cells, GL‐3 accumulates in the lysosomes over time, resulting in phenotypic changes similar to those found in cardiac tissue from Fabry patients. Using this human in vitro model, we demonstrated that substrate reduction therapy via glucosylceramide synthase inhibition was able to prevent accumulation and to clear lysosomal GL‐3 in cardiomyocytes. This new in vitro model recapitulates essential features of cardiomyocytes from patients with Fabry disease and therefore provides a useful and relevant tool for further investigations of new therapy.