bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Cuspidans A and B, Two New Stilbenoids from the Bark of Gnetum cuspidatum.
Authors: Shimokawa Yoko , Hirasawa Yusuke , Kaneda Toshio , Hadi A. Hamid A. , Morita Hiroshi 
Published: October 2012

AbstractCuspidan A (I) shows no cytotoxicity and cuspidan B (II) displays moderate cell growth inhibitory activities against HL‐60 cells.
ChemInform Abstract: Genetic, Biological and Structural Hierarchies During Sponge Spicule Formation: from Soft Sol—Gels to Solid 3D Silica Composite Structures
Authors: Wang Xiaohong , Schroeder Heinz C. , Wang Kui , Kaandorp Jaap A. , Mueller Werner E. G. 
Published: October 2012

AbstractReview: 115 refs.
Number of Leads With Fragmented QRS Predicts Response to Cardiac Resynchronization Therapy
Authors: Celikyurt Umut , Agacdiken Aysen , Sahin Tayfun , Al Neslihan , Kozdag Guliz , Vural Ahmet , Ural Dilek 
Published: October 2012

AbstractBackground:Cardiac resynchronization therapy (CRT) is an effective option in the treatment of patients with heart failure (HF) and wide QRS. Fragmented QRS (fQRS) on 12‐lead electrocardiography has been shown to predict cardiac events in several patient populations. However, the relationship between the number of leads with fQRS and response to CRT has not been investigated.Hypothesis:The number of leads with fQRS may predict response to CRT.Methods:One hundred five patients with HF undergoing CRT were prospectively studied. The presence of fQRS was assessed using standardized criteria. Echocardiographic response to CRT was defined by a ≥15% reduction in left ventricular end‐systolic volume at 6 months follow‐up.Results:Seventy‐four patients (71%) had CRT response after 6 months of follow‐up. In multivariate analysis, significant associates of response to CRT were evaluated adjusting for gender, etiology of cardiomyopathy, QRS width, baseline left ventricular ejection fraction, and the number of leads with fQRS. The number of leads with fQRS was the only predictor of response to CRT (odds ratio: 0.61, 95% confidence interval: 0.48‐0.77, P < 0.001).Conclusions:The more leads with fQRS predicts nonresponse to CRT and may help in the selection of CRT candidates. Clin. Cardiol. 2011 DOI: 10.1002/clc.22061The authors have no funding, financial relationships, or conflicts of interest to disclose.
High‐performance implementation of planted motif problem on multicore and GPU
Authors: Dasari Naga Shailaja , Ranjan Desh , Zubair Mohammad 
Published: October 2012

SUMMARYIn this paper, we present an efficient, easily parallelizable approach to solve planted motif problem (PMP). PMP is a well‐studied problem in computational biology. It is useful in developing methods for finding transcription factor binding sites, classifying sequences, and building phylogenetic trees. Many approaches to solve PMP can be found in the literature. But the problem with those approaches is that they are difficult to parallelize as they have been designed for serial computers. In this paper, we propose a simple, easily parallelizable enumeration‐based approach called BitBased. As with most other enumeration‐based approaches that have been proposed to solve PMP, BitBased is also limited by memory for solving large‐sized problems. To overcome this limitation, we propose various modifications, which not only reduce the memory requirement but also improve the performance of the approach. We have implemented our approach on multicore and GPU devices. We found that BitBased outperforms all the approaches proposed to solve PMP so far. BitBased is able to solve the (21,8) instance, which was not previously reported as solved in the literature. Copyright © 2012 John Wiley & Sons, Ltd.
Coordinated learning by exploiting sparse interaction in multiagent systems
Authors: Yu Chao , Zhang Minjie , Ren Fenghui 
Published: October 2012

SUMMARYMultiagent learning provides a promising paradigm to study how autonomous agents learn to achieve coordinated behavior in multiagent systems. In multiagent learning, the concurrency of multiple distributed learning processes makes the environment nonstationary for each individual learner. Developing an efficient learning approach to coordinate agents’ behavior in this dynamic environment is a difficult problem especially when agents do not know the domain structure and at the same time have only local observability of the environment. In this paper, a coordinated learning approach is proposed to enable agents to learn where and how to coordinate their behavior in loosely coupled multiagent systems where the sparse interactions of agents constrain coordination to some specific parts of the environment. In the proposed approach, an agent first collects statistical information to detect those states where coordination is most necessary by considering not only the potential contributions from all the domain states but also the direct causes of the miscoordination in a conflicting state. The agent then learns to coordinate its behavior with others through its local observability of the environment according to different scenarios of state transitions. To handle the uncertainties caused by agents’ local observability, an optimistic estimation mechanism is introduced to guide the learning process of the agents. Empirical studies show that the proposed approach can achieve a better performance by improving the average agent reward compared with an uncoordinated learning approach and by reducing the computational complexity significantly compared with a centralized learning approach. Copyright © 2012 John Wiley & Sons, Ltd.
Chlorine‐Enhanced Surface Mobility of Au(100)
Authors: Mesgar Mostafa , Kaghazchi Payam , Jacob Timo , Pichardo‐Pedrero Ernesto , Giesen Margret , Pichardo‐Pedrero Ernesto , Giesen Margret , Ibach Harald , Luque Noelia B. , Schmickler Wolfgang 
Published: October 2012

AbstractMotivated by experimental studies of two‐dimensional Ostwald ripening on Au(100) electrodes in chlorine‐containing electrolytes, we have studied diffusion processes using density functional theory. We find that chlorine has a propensity to temporary form AuCl complexes, which diffuse significantly faster than gold adatoms. With and without chlorine, the lowest activation energy is found for the exchange mechanism. Chlorine furthermore reduces the activation energy for the detachment from kink sites. Kinetic Monte Carlo simulations were performed on the basis of extensive density functional theory calculations. The island‐decay rate obtained from these Monte Carlo simulations, as well as the decay rate obtained from the theoretical activation energies and frequency factors when inserted into analytical solutions for Ostwald ripening, are in agreement with experimental island‐decay rates in chlorine‐containing electrolytes.
In Situ Intercalating Expandable Graphite for Mesoporous Carbon/Graphite Nanosheet Composites as High‐Performance Supercapacitor Electrodes
Authors: Wang Lei , Mu Guang , Tian Chungui , Sun Li , Zhou Wei , Tan Taixing , Fu Honggang 
Published: October 2012

AbstractMesoporous‐carbon‐coated graphite nanosheet (GNS@MC) composites have been synthesized by the intercalation of resol prepolymer into the interlayers of expandable graphite (EG) under vacuum‐assisted conditions, followed by the exfoliation of EG through in situ polymerization, the growth of resol under hydrothermal conditions, and carbonization under Ar. The GNS@MC composites exhibit enhanced capacitive performance compared to mesoporous carbon (MC), microwaved EG after thermal treatment (T‐EG), and the physical mixture of MC and T‐EG (MC+T‐EG). In particular, the GNS@MC‐35‐800 composite carbonized at 800 °C, which has a graphite‐nanosheet content of 35 % and a Brunauer–Emmett–Teller surface area (SBET) of 432.3 m2 g−1, exhibits the highest capacitance of 203 F g−1 at 1 A g−1 in 6 M KOH electrolyte. Furthermore, the GNS@MC‐35‐800 composite exhibits a good cyclic stability with 95 % capacitance retention and a high columbic efficiency of 99 % after 5000 cycles. The energy density of the symmetric supercapacitor GNS@MC‐35‐800/GNS@MC‐35‐800 achieved was as high as 11.5 Wh kg−1 at a high power density of 10 kW kg−1. This good performance is attributable to the GNSs in the GNS@MC composite facilitating electron transport owing to its excellent conductivity; moreover, the MC in GNS@MC favors the rapid diffusion of ions by providing low‐resistance pathways. The GNS@MC composite may find application in high‐performance energy storage and conversion devices.
Yeast Genomics Technique for High‐Throughput Drug Target Discovery
Authors: Sun Zijun , Sun Yanyan , Zhou Yaxian , Wan Yakun 
Published: October 2012

Abstract

Preclinical Research

The budding yeast Saccharomyces cerevisiae has been a singularly useful eukaryote for the development of Chemical genomic techniques for use in drug discovery studies. Particularly, yeast genomic methodologies provide a solid foundation for high‐throughput drug target identification. The success of genomic profiling in budding yeast led to the use of chemical genomics approaches in higher eukaryotic systems. In the present overview, the focus was principally on high‐throughput chemical genomic technologies that are advancing the utility of yeast in the drug development research. This led to the review of chemical genomic technologies in other biological systems and the applications of drug synergy in pharmacological research. Finally, the development of genome‐wide drug screening was reviewed in the context of drug synergy strategies for discovering novel combinatorial therapies.
Ribonomic Approaches to Identify Protein–mRNA and microRNA–mRNA Interactions: Implications for Drug Design
Authors: Dziublenski Matthew , Roff Alanna N. , Ishmael Faoud T. 
Published: October 2012

Abstract

Preclinical Research

Posttranscriptional regulation of gene expression is now recognized to play a large role in physiological and pathological processes. Through interactions with messenger ribonucleic acid (mRNA), RNA‐binding proteins (RBPs) and microRNAs (miRNAs) can alter mRNA stability or translation. Aberrant function of these pathways may play a role in inflammatory diseases and cancer, making these attractive therapeutic targets. miRNAs and some RBPs, such as tristetraprolin (TTP), destabilize mRNA and may inhibit translation. Other RBPs, such as HuR, may increase mRNA stability to upregulate gene expression. Each RBP or a single miRNA has the potential to regulate multiple functionally related targets by binding to specific sequences or motifs on mRNA. Identification of these regulatory interactions has become a key step in understanding how gene expression is controlled and in designing drugs to target these interactions in disease. A number of ribonomic techniques have been developed to accurately identify RBP–mRNA and miRNA–mRNA binding interactions, including immunoprecipitation and affinity purification techniques combined with microarray technology and high‐throughput deoxyribonucleic acid (DNA) sequencing. Information gained from these approaches can be used to design agents that mimic or inhibit these regulatory interactions and thus represents a novel strategy for the treatment of disease.
Harnessing Omics Sciences, Population Databases, and Open Innovation Models for Theranostics‐Guided Drug Discovery and Development
Authors: Dove Edward S. , Özdemir Vural , Joly Yann 
Published: October 2012

Abstract

Preclinical Research

Omics science‐driven population databases and biobanks help in enabling robust, large‐scale, high‐throughput biomarker discovery and validation. As targeted drug therapies will require the development of companion diagnostic tests to identify patients most suitable for a given drug therapy, databases and biobanks represent one of the optimal and rapidly emerging ways to enable personalized medicine with reduced development timelines. Moreover, data‐intensive omics technologies represent a new dual reconfiguration of 21st‐century science whereby communitarian value‐driven “infrastructure science” and individual entrepreneurship‐driven “discovery science” now coexist. In the hope of overcoming the “transfer problem” in omics research that continues to hinder the full realization of concrete applications for human health, biobanks and databases are increasingly harnessing various open innovation models, such as open access, open source, expert sourcing, and patent pools. These models appear at various stages (drug repurposing, upstream, and downstream) of the research and development (R&D) process. While laudable, their inclusion will likely spur a variety of ethical, legal, and social issues (ELSI), including those revolving around consent, privacy, and property. By collectively anticipating and analyzing these issues, tensions among these innovation models and extant laws and policies regulating biomedical research and therapeutics based on the classical discovery science model can be resolved. This article does not posit which models will work best to achieve drug discovery and development breakthroughs, but rather, advocates for evidence‐based analyses that couple technical and economic data with global ELSI research to foster a more nuanced, contextualized, and thorough understanding of the new dual configuration of postgenomics pharmaceutical R&D.
Social novelty enhances brain cell proliferation, cell survival, and chirp production in an electric fish, Apteronotus leptorhynchus
Authors: Dunlap Kent D. , Chung Michael 
Published: October 2012

AbstractFor many animals, enriched environments and social interaction promote adult neurogenesis. However, in some cases, the effect is transient, and long‐term environmental stimuli have little benefit for neurogenesis. In electric fish, Apteronotus leptorhynchus, fish housed in pairs for 7 days show higher density of newborn brain cells (cell addition) than isolated fish, but fish paired for 14 days have rates of cell addition similar to isolated controls. We examined whether introduction of social novelty can sustain elevated levels of cell addition and prevent long‐term habituation to social interaction. We also monitored electrocommunication signals (“chirps”) as a measure of the behavioral response to social novelty. We paired fish for 14 days with one continuous partner (no social novelty), two sequential partners changed after 7 days (low novelty) or seven sequential partners changed every 2 days (high novelty). On Day 11, we injected fish with BrdU, sacrificed fish 3 days later and quantified BrdU labeling in the diencephalic periventricular zone. Fish exposed to no novelty had BrdU labeling similar to isolated fish. Fish with low novelty showed small increases in BrdU labeling and those with high novelty had much greater BrdU labeling. Similarly, chirp rates were greater in fish with low novelty than with no novelty and greatest yet in fish with high novelty. By varying the timing of novelty relative to BrdU injection, we showed that social novelty promoted both proliferation and survival of newborn cells. These results indicated that brain cell proliferation and survival is influenced more by social change than simply the presence of social stimuli. © 2012 Wiley Periodicals, Inc. Develop Neurobiol, 2013
Synthesis and Stability Studies of α,α‐Difluoro Ester Phospholipids
Authors: Pedersen Palle J. , Andresen Thomas L. , Clausen Mads H. 
Published: October 2012

AbstractThe synthesis of two new α,α‐difluoro ester phospholipid conjugates is described and the stability of their liposomal formulations in three different aqueous buffers (pH 4.5, 7.5 and 8.5) has been investigated. The studies confirmed that α,α‐difluoro esters are much more prone to hydrolysis when positioned close to the hydrophilic head group of phospholipids than when the functionality is placed in the lipophilic part of the bilayer in liposomes. This observation lends further support to the concept of protecting hydrolysable functionalities by formulation as part of the membrane of liposomes.
Abnormalities of the der(12)t(12;21) in ETV6‐RUNX1 acute lymphoblastic leukemia
Authors: Al‐Shehhi Halima , Konn Zoe J. , Schwab Claire J. , Erhorn Amy , Barber Kerry E. , Wright Sarah L. , Gabriel Alem S. , Harrison Christine J. , Moorman Anthony V. 
Published: October 2012

AbstractETV6‐RUNX1 fusion [t(12;21)(p13;q22)] occurs in 25% of childhood B‐cell precursor acute lymphoblastic leukemia (BCP‐ALL) and is associated with a favorable outcome. Additional abnormalities involving der(21)t(12;21) and nonrearranged chromosome 12 are well characterized but aberrations involving the der(12)t(12;21) have rarely been described. Herein, we describe two novel abnormalities affecting the der(12)t(12;21): a deletion (20/247, 8%) and duplication (10/247, 4%). All 30 patients were under 10 years of age, had a median white blood count of 12.4 × 109/L and 19.2 × 109/L, respectively, with a good outcome. Deletions of der(12)t(12;21) on both sides of the breakpoint were confirmed and mapped: centromeric (12p11.21‐12p13.2) and telomeric (21q22.12‐21q22.3). The size of these deletions extended from 0.4–13.4 to 0.8–2.5 Mb, respectively. The centromeric deletion encompassed the following genes: LRP6, BCL2L14, DUSP16, CREBL2, and CDKN1B. We postulate that this deletion occurs at the same time as the translocation because it was present in all ETV6–RUNX1‐positive cells. A second abnormality representing duplication of the reciprocal RUNX1–ETV6 fusion gene was a secondary event, which we hypothesize arose through mitotic recombination errors. This led to the formation of the following chromosome: der(12)(21qter→21q22.12::12p13.2‐12p12.3::12p12.3→12qter). Both abnormalities affect the reciprocal RUNX1–ETV6 fusion product which could either eliminate or amplify its expression and thus contribute to leukemogenesis. However, other consequences such as haploinsufficiency of tumor suppressor genes and amplification of oncogenes could also be driving forces behind these aberrations. In conclusion, this study has defined novel abnormalities in ETV6–RUNX1 BCP‐ALL, which implicate new genes involved in leukemogenesis. © 2012 Wiley Periodicals, Inc.
Music therapy in dementia: a narrative synthesis systematic review
Authors: McDermott Orii , Crellin Nadia , Ridder Hanne Mette , Orrell Martin 
Published: October 2012

ObjectiveRecent reviews on music therapy for people with dementia have been limited to attempting to evaluate whether it is effective, but there is a need for a critical assessment of the literature to provide insight into the possible mechanisms of actions of music therapy. This systematic review uses a narrative synthesis format to determine evidence for effectiveness and provide insight into a model of action.MethodThe narrative synthesis framework consists of four elements: (i) theory development; (ii) preliminary synthesis of findings; (iii) exploration of relationships between studies; and (iv) assessment of the robustness of the synthesis.ResultsElectronic and hand searches identified 263 potentially relevant studies. Eighteen studies met the full inclusion criteria. Three distinctive strands of investigations emerged: eight studies explored behavioural and psychological aspects, five studies investigated hormonal and physiological changes, and five studies focused on social and relational aspects of music therapy. The musical interventions in the studies were diverse, but singing featured as an important medium for change.ConclusionsEvidence for short‐term improvement in mood and reduction in behavioural disturbance was consistent, but there were no high‐quality longitudinal studies that demonstrated long‐term benefits of music therapy. Future music therapy studies need to define a theoretical model, include better‐focused outcome measures, and discuss how the findings may improve the well‐being of people with dementia. Copyright © 2012 John Wiley & Sons, Ltd.
Diastereoselective Coupling of N‐(tert‐Butyl)sulfinyl Imines and Dimethyl Malonate. Synthesis of Enantiomerically Enriched β‐Amino Esters and β‐Lactams
Authors: Dema Haythem K. , Foubelo Francisco , Yus Miguel 
Published: October 2012

AbstractA diastereoselective coupling of dimethyl malonate with N‐(tert‐butyl)sulfinyl imines under solvent‐free conditions was developed, using NaHCO3 or NaI as base promoters. The resulting dimethyl 2‐(1‐aminoalkyl)malonates could be easily transformed successively to β‐amino esters and the corresponding β‐lactams with high optical purity.
Some Aspects of the Chemistry of Nitro Compounds
Authors: Zard Samir Z. 
Published: October 2012

AbstractThe present brief account relates our discovery of new reactions revolving around the chemistry of the NO2 group. It covers the condensation of MeNO2 with hindered ketones, and the synthesis of pyrroles, triazoles, and enamides. It also describes new transformations of allylic nitro compounds, such as their conversion to allylic sulfones and unsaturated lactones, their sigmatropic rearrangement into allylic nitrites and thence into allylic alcohols, as well as their use in a short synthesis of nitroestrone derivatives. This is followed by an unusual reduction method furnishing unsubstituted amines (RR′CNH) under conditions where these hydrolytically labile species can be captured inter‐ or intramolecularly. Finally, a mechanistic study of a strange alkyne‐forming reaction, first reported by Abidi and later shown by Corey and co‐workers to proceed through allylic nitro intermediates, ultimately led to a practical and powerful synthesis of alkynes starting from β‐keto esters.
Synthesis of Perfluoroalkyl‐Substituted γ‐Lactones and 4,5‐Dihydropyridazin‐3(2H)‐ones via DonorAcceptor Cyclopropanes
Authors: Gladow Daniel , Reissig Hans‐Ulrich 
Published: October 2012

AbstractRh2(OAc)4‐Catalyzed decomposition of diazo esters in the presence of perfluoroalkyl‐ or perfluoroaryl‐substituted silyl enol ethers smoothly provided the corresponding alkyl 2‐siloxycyclopropanecarboxylates in very good yields. The generated donoracceptor cyclopropanes are equivalents of γ‐oxo esters, which we demonstrated by their one‐pot transformations to yield fluorine‐containing heterocycles. A reductive procedure selectively afforded perfluoroalkyl‐substituted γ‐hydroxy esters or γ‐lactones. The treatment of the donoracceptor cyclopropanes with hydrazine or phenylhydrazine afforded a series of perfluoroalkyl‐ and perfluoroaryl‐substituted 4,5‐dihydropyridazin‐3(2H)‐ones.
Cross‐Linked‐Polymer‐Supported N‐{2′‐[(Arylsulfonyl)amino][1,1′‐binaphthalen]‐2‐yl}prolinamide as Organocatalyst for the Direct Aldol Intermolecular Reaction under Solvent‐Free Conditions
Authors: Bañón‐Caballero Abraham , Guillena Gabriela , Nájera Carmen 
Published: October 2012

AbstractA bottom‐up strategy was used for the synthesis of cross‐linked copolymers containing the organocatalyst N‐{(1R)‐2′‐{[(4‐ethylphenyl)sulfonyl]amino}[1,1′‐binaphthalen]‐2‐yl}‐D‐prolinamide derived from 2 (Scheme 1). The polymer‐bound catalyst 5b containing 1% of divinylbenzene as cross‐linker showed higher catalyst activity in the aldol reaction between cyclohexanone and 4‐nitrobenzaldehyde than 5a and 5c. Remarkably, the reaction in the presence of 5b was carried out under solvent‐free, mild conditions, achieving up to 93% ee (Table 1). The polymer‐bound catalyst 5b was recovered by filtration and re‐used up to seven times without detrimental effects on the achieved diastereo‐ and enantioselectivities (Table 2). The catalytic procedure with polymer 5b was extended to the aldol reaction under solvent‐free conditions of other ketones, including functionalized ones, and different aromatic aldehydes (Table 3). In some cases, the addition of a small amount of H2O was required to give the best results (up to 95% ee). Under these reaction conditions, the cross‐aldol reaction between aldehydes proceeded in moderate yield and diastereo‐ and enantioselectivity (Scheme 2).