bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catalytic Asymmetric Hydrogenation of Ethyl 2‐(Benzo[b]thiophen‐5‐yl)‐2‐oxoacetate with Ru‐SunPhos in the Formal Synthesis of T‐588
Authors: Li Xiaoming , Ma Xin , Li Wanfang , Tao Xiaoming , Meng Qinghua , Fan Weizheng , Zhang Zhaoguo 
Published: December 2011

AbstractApplication of catalytic asymmetric hydrogenation of ethyl 2‐(benzo[b]thiophen‐5‐yl)‐2‐oxoacetate for the formal synthesis of cognitive enhancer T‐588 is described. The hydrogenation was conducted under the catalysis of Ru‐SunPhos system with HCl as additive. Ethyl 2‐(benzo[b]thiophen‐5‐yl)‐2‐hydroxy‐acetate was obtained with 98.6% ee, which could be easily upgraded to 99.5% ee after a simple recrystallization and served as the key intermediate in the synthesis of T‐588.
An Effective Synthesis of Indazolo[2,1‐a]indazole‐6,12‐diones by Regioselective Copper‐Catalyzed Cascade Acylation/Coupling Cyclization Process
Authors: Wang Zhiming , Yu Bin , Cui Yuan , Sun Xiaoqiang , Bao Weiliang 
Published: December 2011

AbstractA new and efficient cascade synthesis of indazolo[2,1‐a]indazole‐6,12‐diones has been developed. This protocol includes an intermolecular N‐acylation followed by a copper‐catalyzed intramolecular CN coupling reaction. The methodology is applied to a wide range of 2‐bromo and 2‐chloro benzoyl chlorides to yield the indazolo‐[2,1‐a]indazole‐6,12‐diones in good to excellent yields with high regioselectivities.
Study on the Interaction between Cephalosporin Drugs and Papain by Spectroscopic Method: Equivalence of Fluorescence Quenching and Enhancement Equation
Authors: Yang Manman , Xi Xiaoli , Yang Pin 
Published: December 2011

AbstractThe interaction between two 4th generation of new cephalosporin drugs and papain was studied through spectroscopy method at different temperatures. Their dissociation constants were calculated by using theoretical formula of fluorescence quenching and fluorescence enhancement, respectively, and their corresponding thermodynamic functions, dipole‐dipole non‐radiative energy‐transfer‐efficiency and the action distances of acceptor‐substrateetc. were calculated further. Analysis reveals that, the quenching on papain by cefpirome and cefepime is basically due to the dipole‐dipole non‐radiation energy‐transfer and certain dynamic collision between donor and acceptor, the interaction between drug and papain is mainly hydrophobic which may provide useful information for pharmacological and metabolic study on papain. In this paper fluorescence quenching is regarded as negative fluorescence enhancement, and two kinds of theoretical formula of fluorescence quenching and fluorescence enhancement were used to calculate the experimental data of fluorescence quenching of a same batch, and very close results were obtained but with certain difference. The results not only display the equivalence of the two theoretical equations when treating acceptor‐substrate action, but also show that the thermodynamic data based on the theoretical formula of fluorescence enhancement (4), which is deduced by us, are more reasonable. So we suggest that even in the process of studying the fluorescence quenching between receptor‐substrate, using the theoretical formula of fluorescence enhancement (4) can get more reliable results.
Synthesis of 14‐Fluorophenyl‐14H‐Dibenzo[a,j]xanthenes and Their Derivatives under Microwave Irradiation and Solvent‐free Conditions
Authors: Jin Jianan , Zhang Jianmin , Shang Wenli , Zhu Shizheng 
Published: December 2011

AbstractA facile and efficient synthesis of 14‐fluorophenyl‐14H‐dibenzo[a,j]xanthenes has been developed by one‐pot condensation of fluorinated benzaldehydes with β‐naphthol in the presence of p‐TSA·H2O under microwave irradiation and solvent‐free conditions. These products are conveniently oxidized to 14‐fluorophenyl‐14‐hydroxy‐dibenzo[a,j]xanthenes by PbO2 in acetic acid in good yields.
Identification of Aspartic Acid Enantiomers Based on Molecularly Imprinted Polyaniline
Authors: Kong Yong , Yao Chao , Ni Junhua , Zhou Yongsheng , Chen Zhidong 
Published: December 2011

AbstractAffinity sites for L‐aspartic acid (L‐Asp) in polyaniline (PAn) were created by two successive processes: first, L‐Asp was simply added as template molecules during the polymerization of aniline; second, L‐Asp incorporated in PAn backbone was extracted by solvent. PAn with cavities complementary to L‐Asp template molecules has been utilized for enantioselective recognition of L‐ and D‐Asp. Enantioselectivity of the imprinted PAn could be attributed to the cavities in the imprinted PAn which was complementary to L‐Asp templates both in shape and in positioning of groups. Also in this paper, the structural changes before and after extraction of L‐Asp templates were revealed by Fourier‐transform infrared (FTIR) spectrum.
Reversible Disassembly and Intercalation of 2‐Ureido‐4[1H]‐Pyrimidinone Quadruple Hydrogen‐bonded Supramolecular Assembly by Fluoride and Lead Ions
Authors: Yu Maolin , Zhao Chunchang , Feng Ke , Chen Bin , Tung Chenho , Zheng Yan‐Song , Wu Lizhu 
Published: December 2011

Abstract2‐Ureido‐4[1H]‐pyrimidinone quadruple hydrogen‐bonded assembly 1·1 containing N,N‐dimethylaminophenyl moiety exhibits a sensitive response to fluoride anion and lead cation. Spectroscopic studies reveal that the presence of small amount of fluoride anions and lead cations can easily disassemble and intercalate 2‐ureido‐4[1H]‐pyrimidinone hydrogen‐bonded supramolecular architectures.
A Green and Novel Method for the Synthesis of 4,4‐Difluoro‐3‐oxo‐2‐(triphenylphosphoranylidene) δ‐Lactones by Reformatsky Reaction
Authors: Ibrayim Saidalimu , Fang Xiang , Zhang Dong , Liu Lu , Wu Fanhong 
Published: December 2011

AbstractIn the presence of In/CuCl, ethyl 4‐bromo‐4,4‐difluoro‐3‐oxo‐2‐(triphenylphosphoranylidene)butanoate reacted with various aldehydes in aqueous medium at room temperature to give the α,α‐difluorinated β‐hydroxy carbonyl compounds. Furthermore, treating Reformatsky addition compounds with 1 equiv. of sodium hydroxide in the mixture of tetrahydrofuran and water afforded gem‐di?uoromethylenated 2‐triphenylphosphoranylidene δ‐lactones in excellent yields.
Synthesis of CMOS analog circuit VHDL‐AMS descriptions using parameterizable macromodels
Authors: Doménech‐Asensi G. , Díaz‐Madrid J. A. , Ruiz‐Merino R. 
Published: December 2011

SUMMARYSome of the advantages of very high speed integrated circuits hardware description language for analog and mixed signal (VHDL‐AMS) when used to describe analog circuits are its modeling capability and the speed of simulations, in comparison with device level simulators. However, VHDL‐AMS does not allow one to complete in a systematic way the synthesis of an analog circuit from higher description levels of the design hierarchy to lower ones. This is due to the lack of CAD tools and methods for analog circuits, contrary to the situation of pure digital circuits. This is a serious drawback because it is an obstacle to its success in analog CAD tools. The proposal described in this article, on the basis of the use of parameterizable macromodels, allows a systematic and rapid translation from a VHDL‐AMS description of analog circuits to schematic level‐sized descriptions. Copyright © 2011 John Wiley & Sons, Ltd.
Evaluation of expanded allowable capacity of wind power in power systems by charge control for plug‐in hybrid electric vehicles
Authors: Takagi Masaaki , Yamamoto Hiromi , Yamaji Kenji 
Published: December 2011

AbstractIn recent years, the total capacity of wind power generations is increasing drastically. However, the wind power can negatively influence the power grid frequency because of the output instability. In particular, the problem of frequency fluctuation becomes significant at nighttime, when the capacity of Load Frequency Control (LFC) tends to be insufficient. On the other hand, in the transport sector, the Plug‐in Hybrid Electric Vehicle (PHEV) has been developed as an environmentally friendly vehicle. The batteries of PHEVs are charged mainly during nighttime, when the electricity price is low. Therefore, we propose a charging power control of PHEVs to compensate the LFC capacity in nighttime, and evaluate the expanded allowable capacity of wind power. We obtained the following results. (1) Charging power control can effectively suppress the frequency deviation caused by the output fluctuation of wind power. (2) Even if the number of PHEVs is small, optimum distribution of a daily charge demand could suppress the frequency fluctuation effectively. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(4): 39–48, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21066
Aerial flashover caused by surface flashover generated from microscopic pores of insulating solid
Authors: Shirai Jotaro , Shigefuku Akinao , Murakami Yoshinobu , Hozumi Naohiro , Nagao Masayuki , Natsume Kenji , Naito Norikazu , Hatano Kazuhisa , Kawamura Hirotoshi 
Published: December 2011

AbstractThis paper studies the possibility of an aerial flashover between a coil conductor and the casing in a rotating machine at voltages below Paschen's voltage even when sufficient insulation distance has been provided. It might be considered that partial surface flashover generated from microscopic pores of a solid insulator generates the aerial flashover. In this study, the flashover voltage was measured using a cable which had simulated microscopic pores to confirm the above reasoning. When a potential gradient existed on the surface of the insulating solid, the flashover voltage decreased from that in the absence of a potential gradient. It also became clear that the aerial flashover probability depends mainly on the energy of the surface flashover rather than the energy of the main aerial flashover. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(4): 16–23, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21221
Cthrc1 is a negative regulator of myelination in schwann cells
Authors: Apra Caroline , Richard Laurence , Coulpier Fanny , Blugeon Corinne , Gilardi‐Hebenstreit Pascale , Vallat Jean‐Michel , Lindner Volkhard , Charnay Patrick , Decker Laurence 
Published: December 2011

AbstractThe analysis of the molecular mechanisms involved in the initial interaction between neurons and Schwann cells is a key issue in understanding the myelination process. We recently identified Cthrc1 (Collagen triple helix repeat containing 1) as a gene upregulated in Schwann cells upon interaction with the axon. Cthrc1 encodes a secreted protein previously shown to be involved in migration and proliferation in different cell types. We performed a functional analysis of Cthrc1 in Schwann cells by loss‐of‐ and gain‐of‐function approaches using RNA interference knockdown in cell culture and a transgenic mouse line that overexpresses the gene. This work establishes that Cthrc1 enhances Schwann cell proliferation but prevents myelination. In particular, time‐course analysis of myelin formation intransgenic animals reveals that overexpression of Cthrc1 in Schwann cells leads to a delay in myelin formation with cells maintaining a proliferative state. Our data, therefore, demonstrate that Cthrc1 plays a negative regulatory role, fine‐tuning the onset of peripheral myelination. © 2011 Wiley Periodicals, Inc.
Protocolized post‐operative pain management in infants; do we stick to it?
Authors: Ceelie I. , de Wildt S.N. , de Jong M. , Ista E. , Tibboel D. , van Dijk M. 
Published: December 2011

AbstractBackgroundThe American Academy of Pediatrics states that ongoing assessment of pain is essential for adequate pain treatment. Pain assessment by means of the COMFORT behaviour scale and the Numeric Rating Scale is therefore an important component of the post‐operative pain treatment protocol for neonates and infants in our intensive care unit (ICU).AimThe study aims to determine degrees of staff compliance with this protocol.Patients and methodsThis retrospective chart review concerned post‐surgical patients under the age of 3 years admitted to our level III ICU over a 1‐year period. The degree of compliance to the post‐operative pain protocol was measured by the frequency of deviations from protocol‐dictated drug treatment and pain assessments.ResultsRecords of 200 children with a median age at surgery of 98 days (interquartile range 6–320) were analysed. A mean of 11 assessments in the first 72 h post‐operatively per patient had been recorded. A total of 2103 pain assessments were retrieved, of which 1675 (79.7%) suggested comfort. Compliance to the protocol (reassessment and correct medication) was provided in 66 (15.4%) of the 428 assessments suggesting pain or distress.ConclusionThe post‐operative pain protocol applied in our ICU appears to be effective; however, full compliance to the protocol was marginal, possibly leading to under‐treatment of pain.
Marathon runners’ reaction to potassium iontophoretic experimental pain: Pain tolerance, pain threshold, coping and self‐efficacy
Authors: Johnson M.H. , Stewart J. , Humphries S.A. , Chamove A.S. 
Published: December 2011

AbstractThere is equivocal evidence regarding pain responding in endurance athletes. When performing, their pain experience appears reduced but it is uncertain whether this persists when not competing or training. This study aimed to clarify how marathon runners perceive pain, and the influence of self‐efficacy and coping strategy use on their pain threshold and tolerance when they are not affected by immediate exercise. Pain threshold and pain tolerance were assessed in 26 marathon runners and 26 age‐ and sex‐matched non‐runners using potassium iontophoresis as the experimental pain stimulus. Use of associative and dissociative coping strategies, and catastrophizing were assessed using the Cognitive Coping Strategies Inventory, and pain specific and general self‐efficacy were measured. Elevated pain threshold, pain tolerance and self‐efficacy in marathon runners were revealed. Pain specific self‐efficacy accounted for 40% of the tolerance difference between the marathon and non‐marathon groups. Coping and catastrophizing did not differ between the two groups but higher associative coping when accompanied by lower dissociative coping was related to higher pain tolerance. These results indicate that marathon runners have a reduced experience of pain compared with non‐runners. This ability appears to be augmented by a high level of pain specific self‐efficacy but is unaffected by the influence of general cognitive coping strategies, although higher associative coping and lower dissociative coping together were related to reduced pain tolerance independent of running involvement.
Effects of sub‐perception threshold spinal cord stimulation in neuropathic pain: A randomized controlled double‐blind crossover study
Authors: Wolter T. , Kiemen A. , Porzelius C. , Kaube H. 
Published: December 2011

AbstractBackgroundRecent studies suggest that perception of the paraesthesia elicited by spinal cord stimulation (SCS) is not necessarily required for the pain relieving effect.ObjectiveThe purpose of the study was to determine the effect of sub‐perception threshold SCS in patients with neuropathic pain.MethodsTen patients with implanted SCS systems underwent continuous sub‐threshold stimulation and no stimulation in a blinded randomized crossover design. Pain scores under these treatment modalities were compared with usual supra‐threshold stimulation.ResultsSub‐threshold stimulation elicited significantly lower pain relief than supra‐perception threshold SCS. Mean pain scores were 3.6 [max 6.3, min 1.9, standard deviation (SD) 1.3] under supra‐threshold stimulation, 5.6 (max 9.0, min 2.4, SD 1.9) under sub‐threshold stimulation and 6.4 (max 10.0, min 4.0, SD 2.0) without stimulation.ConclusionSub‐threshold stimulation under otherwise conventional stimulation parameters has a measurable but not clinically sufficient effect. Thus, the pain relieving effect elicited by SCS is not necessarily linked to the perceptibility of stimulation but may instead be attributed to the intensity of the electric field.
Differences in perception and brain activation following stimulation by large versus small area cutaneous surface electrodes
Authors: Lelic D. , Mørch C.D. , Hennings K. , Andersen O.K. , Drewes A.M. 
Published: December 2011

AbstractIntroductionApplication of electrical stimulation through conventional surface electrodes activates both non‐nociceptive and nociceptive fibres. To encompass this problem, electrical stimulation through small area pin electrode was introduced where subjective description of stimulation quality indicated preferential activation of nociceptors. The present study aimed to show that brain areas involved in nociceptive processing are activated by stimulation through cutaneous pin electrode (CPE) to a larger extent than conventional surface electrodes.MethodsEvoked potentials (EPs) were induced by electrical stimulation through conventional surface andCPEelectrodes. TheEPswere recorded from 62 scalp electrodes in 12 healthy volunteers where stimulation intensity was 10 times the sensory threshold. Dipolar models of brain sources were built by using the brain electrical source analysis.ResultsThe solution for the conventional large area surface electrode was a four‐dipole model including contralateral primary somatosensory cortex, bilateral secondary somatosensory cortex (SII) and mid‐cingulate sources. The solution forCPEwas a five‐dipole model and very similar to that previously described to explain the topography of laserEPs. The solution included bilateralSII, bilateral insula and mid‐cingulate sources. Since laser stimuli mainly activate nociceptive fibres, the strong similarity suggests that mainly nociceptive inputs are involved in generation ofCPE‐evoked responses.ConclusionThe current study gives evidence thatCPEactivates the nociceptive brain areas to a greater extent than conventional surface electrode. Therefore,CPEshould preferentially be utilized in future studies where electrical stimuli are used to study nociception.
Using graded motor imagery for complex regional pain syndrome in clinical practice: Failure to improve pain
Authors: Johnson S. , Hall J. , Barnett S. , Draper M. , Derbyshire G. , Haynes L. , Rooney C. , Cameron H. , Moseley G.L. , de C. Williams A.C. , McCabe C. , Goebel A. 
Published: December 2011

AbstractBackgroundThere is good evidence from studies conducted in a single‐centre research setting for the efficacy of graded motor imagery (GMI) treatment, a complex physiotherapy intervention, to reduce pain in long‐standing complex regional pain syndrome (CRPS). However, whether GMI is effective in clinical practice is not established.AimTo establish whether GMI is effective in clinical practice.MethodsWe undertook a prospective audit of GMI treatment at two UK centres with a special interest in the management of patients with CRPS. All patients received GMI, in conjunction with a range of other ‘best practice’ physical and psychological interventions.ResultsThe patients' average pain intensities did not improve with treatment [centre 1: n = 20, pre‐post numeric rating scale (NRS) difference 0.6 [confidence interval (CI) −0.3 to 1.5]; centre 2: n = 12, pre‐post NRS difference 0.2 (CI: −0.9 to 1.2)]. Patients at centre 1 reported significant functional improvement. Improved performance on left/right judgement replicated in both centres seen in the clinical trials.ConclusionsThe failure of our real‐world implementation of GMI suggests that better understanding of both the GMI methodology and its interaction with other treatment methods is required to ensure that GMI research results can be translated into clinical practice. Our results highlight challenges with the translation of complex interventions for chronic pain conditions into clinical practice.
Plasma corticosterone levels in mouse models of pain
Authors: Benedetti M. , Merino R. , Kusuda R. , Ravanelli M.I. , Cadetti F. , dos Santos P. , Zanon S. , Lucas G. 
Published: December 2011

AbstractBackgroundPain markedly activates the hypothalamic‐pituitary‐adrenal (HPA) axis and increases plasma corticosterone release interfering significantly with nociceptive behaviour as well as the mechanism of action of analgesic drugs.Aims/MethodsIn the present study, we monitored the time course of circulating corticosterone in two mouse strains (C57Bl/6 and Balb/C) under different pain models. In addition, the stress response was investigated following animal handling, intrathecal (i.t.) manipulation and habituation to environmental conditions commonly used in nociceptive experimental assays. We also examined the influence of within‐cage order of testing on plasma corticosterone.ResultsSubcutaneous injection of capsaicin precipitated a prompt stress response whereas carrageenan and complete Freund's adjuvant induced an increased corticosterone release around the third hour post‐injection. However, carrageenan induced a longer increased corticosterone in C57Bl/6 mice. In partial sciatic nerve ligation, neuropathic pain model corticosterone increased only in the first days whereas mechanical hypersensitivity remained much longer. Animal handling also represents an important stressor whereas the i.t. injection per se does not exacerbate the handling‐induced stress response. Moreover, the order of testing animals from the same cage does not interfere with plasma corticosterone levels in the intrathecal procedure. Animal habituation to the testing apparatus also does not reduce the immediate corticosterone increase as compared with non‐habituated mice.ConclusionOur data indicate that HPA axis activation in acute and chronic pain models is time dependent and may be dissociated from evoked hyperalgesia. Therefore, HPA‐axis activation represents an important variable to be considered when designing experimental assays of persistent pain as well as for interpretation of data.
The amygdala, a relay station for switching on and off pain
Authors: Rouwette T. , Vanelderen P. , Roubos E.W. , Kozicz T. , Vissers K. 
Published: December 2011

AbstractNeuropathic pain is strongly associated with mood disorders like anxiety and depression. Corticotropin‐releasing factor (CRF) plays a prominent role in these disorders as it is up‐regulated in limbic structures such as the amygdala, upon experimentally induced neuropathy. This review discusses recent literature on the role of CRF in pain processing and highlights the amygdala as a potential hot spot in supraspinal descending pain control. Many studies have demonstrated analgesic effects of CRF following local and systemic administration, but more recently also hyperalgesic effects were shown upon endogenous amygdalar CRF increase or by blocking the CRF type 1 receptor (CRFR1). On the basis of the reviewed literature, we postulate a central mechanism for pain control in which the amygdala plays a critical role by switching on and off chronic pain. In this mechanism, upon pain stimuli, CRFR1 in the amygdala is activated by CRF to induce hyperalgesia. When the activated CRFR1 is internalized (pain initiation), it triggers the translocation of the cytoplasmic CRF type 2 receptor (CRFR2) to the plasma membrane. Here, CRFR2 can be recruited by either high (pharmacological) concentrations of CRF or by endogenous CRFR2 ligands, the urocortins, leading to analgesia (pain termination). This on–off switching of pain is completed by redistribution of the CRF receptors to their initial activity state. We furthermore propose that in neuropathic pain, this mechanism is dysregulated and causes a state of permanent hyperalgesia, and present an integrative (patho)physiological model for the way disturbed CRF receptor signalling in the amygdala could initiate neuropathic pain.