bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Cyclopentadienyl)nitrosylmanganese Compounds: The Original Molecules Containing Bridging Nitrosyl Groups
Authors: Yan Bing , Xie Yaoming , King R. Bruce , Schaefer Henry F. 
Published: July 2009

AbstractThe (cyclopentadienyl)nitrosylmanganese derivatives Cp2Mn2(NO)2(CO)n (n = 2, 1, 0), Cp2Mn2(NO)3X (X = NO2, ‐C5H5), CpMn(NO)2, Cp2Mn2(NO)4, and Cp3Mn3(NO)4 have been investigated by using density functional theory. Six structures are found for Cp2Mn2(NO)2(CO)2 with various combinations of terminal and bridging carbonyl and nitrosyl groups within ca. 3 kcal/mol of each other indicating a highly fluxional system. A triplet‐state triply bridged structure is predicted to be the global minimum for Cp2Mn2(NO)2(CO), just as it is for the isoelectronic Cp2Fe2(CO)3. For Cp2Mn2(NO)2 a doubly bridged triplet structure is predicted to lie ca. 30 kcal/mol below the corresponding singlet structure, unlike the isoelectronic Cp2Fe2(CO)2. The structures predicted for Cp2Mn(µ‐NO)2(NO)X (X = NO2 and η1‐C5H5) and Cp3Mn3(µ‐NO)3(µ3‐NO) are close to the experimentally known structures. The monomer CpMn(NO)2, with a favorable 18‐electron configuration for the manganese atom, is predicted to be unstable with respect to dimerization to Cp2Mn2(µ‐NO)2(NO)2, for which two structures are found of similar energy. One Cp2Mn2(µ‐NO)2(NO)2 structure has a non‐bonding Mn···Mn distance of ca. 3.1 Å and linear terminal MnNO units, whereas the other Cp2Mn2(µ‐NO)2(NO)2 structure has a single‐bond Mn–Mn distance of ca. 2.5 Å and bent terminal MnNO units. In Cp2Mn(µ‐NO)2(NO)(η1‐Cp) the Mn2(µ‐NO)2 unit is unsymmetrical, with significantly different (by ca. 0.2 Å) Mn–N bond lengths to each side. However, in Cp2Mn2(NO)2(CO)n (n = 2, 1, 0) and Cp2Mn2(µ‐NO)2(NO)2 the Mn2(µ‐NO)2 units are symmetrical, with essentially the same Mn–N bond lengths to both sides. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Investigation of a dual CD chiral CE system for separation of glitazone compounds
Authors: Jamali Babak , Bjørnsdottir Inga , Cornett Claus , Honoré Hansen Steen 
Published: July 2009

AbstractA dual CD‐CE method for chiral separation of enantiomers of pioglitazone, rosiglitazone and balaglitazone was investigated for the purpose of optimizing the chiral separation. In a previous work a dual CD chiral CE method was used for investigation of glitazone compounds in drug substance and pharmaceutical formulation and the studies showed that all studied glitazones were racemic mixtures. This CE method could separate the enantiomers with a resolution (RS) of about 3. However, another study on single glitazone enantiomers pointed out that a higher RS is needed to achieve more accurate results for separation of a small amount of one enantiomer in the presence of a high amount of the other enantiomers. The focus of this investigation was thus directed toward the effect of CDs and the pH of the running buffer to achieve a better enantioseparation. Initially CE systems with each of heptakis(2,6‐di‐O‐methyl)‐β‐CD (DM‐β‐CD) and heptakis(6‐sulfobutylether)‐β‐CD (SB‐β‐CD) as single CD added were investigated at three different pH values (2.5, 5.0 and 9.3). After having chosen the best of these three pH values a dual CD system was further investigated and optimized. The optimization work was then focused on the concentration of the two CDs and the pH of the running buffer and was performed using factorial design experiments. A mixture of a DM‐β‐CD and SB‐β‐CD was found to be optimal and necessary to achieve enantioseparation with sufficiently high RS. In order to further verify the importance of the SB‐β‐CD, a CE system with the DM‐β‐CD added and substitution or partial substitution of the SB‐β‐CD by SDS was studied for comparison. 1H‐NMR studies were performed to get a more detailed understanding of the interactions between the glitazones and the CDs used.The optimized dual CD‐CE method for chiral separation of the enantiomers of pioglitazone, rosiglitazone and balaglitazone using a running buffer containing 50 mM borate buffer pH 9.7, 12 mM of SB‐β‐CD and 3 mM of DM‐β‐CD provided a high RS (RS between 5.5 and 8.8).
Combined use of chiral ionic liquid and cyclodextrin for MEKC: Part I. Simultaneous enantioseparation of anionic profens
Authors: Wang Bin , He Jun , Bianchi Victoria , Shamsi Shahab A. 
Published: July 2009

AbstractThe enantiomers of five profen drugs were simultaneously separated by MEKC with the combined use of 2,3,6‐tri‐O‐methyl‐β‐cyclodextrin and chiral cationic ionic liquid, N‐undecenoxy‐carbonyl‐L‐leucinol bromide, which formed micelles in aqueous buffers. Enantioseparations of these profen drugs were optimized by varying the chain length and concentration of the IL surfactant using a standard recipe containing 35 mM 2,3,6‐tri‐O‐methyl‐β‐cyclodextrin, 5 mM sodium acetate at pH 5.0. The batch‐to‐batch reproducibility of N‐undecenoxy‐carbonyl‐L‐leucinol bromide was tested and found to have no significant impact in terms of enantiomeric resolution, efficiency, and migration time. Finally, this method was successfully applied for the quantitative determination of ibuprofen in pharmaceutical tablets.
Gold nanoparticle‐enhanced capillary electrophoresis‐chemiluminescence assay of trace uric acid
Authors: Zhao Shulin , Lan Xuehua , Liu Yi‐Ming 
Published: July 2009

AbstractA sensitive method based on gold nanoparticle‐enhanced CE‐chemiluminescence (CL) detection was developed for quantifying uric acid (UA) in serum. In this work, gold nanoparticles were added into the running buffer of CE to catalyze the post‐column CL reaction between luminol and hydrogen peroxide, achieving highly efficient CL emission. Negative peaks were produced due to the inhibitory effects on CL emission from UA eluted from the electrophoretic capillary. The decrease in CL intensity was proportional to the concentration of UA in the range of 2.5×10−7–1.0×10−5 M. Detection limit was 4.6×10−8 M UA. Ten human serum samples were analyzed by the presented method. Serum level of UA was found to be in the range from 204 to 324 μM for healthy subjects (n=5), and from 464 to 497 μM for diabetic patients (n=5). The two groups were significantly different (p<0.05). The results suggested a potential application of the proposed assay in rapid primary diagnosis of diseases such as diabetes.
Complexity of resilient network optimisation
Authors: Żotkiewicz Mateusz , Pióro Michał , Tomaszewski Artur 
Published: July 2009

AbstractPath restoration (PR) is one of the basic mechanisms for securing telecommunication networks against failures. In the paper, we discuss the complexity of certain variants of a multi‐commodity flow network optimisation problem in directed graphs related to state‐independent path restoration mechanisms. We demonstrate that most variants of the considered problem are $\cal{NP}$‐hard. Depending on the variant, we show how the problem can be reduced either from the partition problem or from the problem of finding an arc‐disjoint pair of paths that connect two distinct pairs of nodes. We also demonstrate that at the same time the considered problem is difficult to approximate. The complexity results of the paper are important as they can help to devise proper algorithms for resilient network design tools. Copyright © 2009 John Wiley & Sons, Ltd.
Persistence in some energy futures markets
Authors: Cunado Juncal , Gil‐Alana Luis A. , Perez de Gracia Fernando 
Published: July 2009

AbstractIn this study, we examine the possibility of long‐range dependence in some energy futures markets for different maturities. In order to test for persistence, we use a variety of techniques based on non‐parametric, semi‐parametric and parametric methods. The results indicate that there is little or no evidence of long memory in gasoline, propane, oil and heating oil at different maturities. However, when we focus on the volatility process, proxied by the absolute returns, we find strong evidence of long memory in all the variables at different contracts. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 30:490–507, 2010
Size clustering in the FTSE100 index futures market
Authors: ap Gwilym Owain , Meng Lei 
Published: July 2009

AbstractRecent literature has begun to explore size clustering in financial markets. If a market is perfectly liquid, traders should be able to trade the exact amount that they desire; however, the presence of size clustering may prevent them from achieving optimal trade sizes. This study is novel in its investigation of size clustering in a futures market. We find that trade sizes cluster in a manner that is similar to the pattern of price clustering found in many financial markets. Importantly, we identify a trade‐off between size resolution and price resolution. We also find that the number of distinct trade sizes increases with trade frequency and with intra‐day volatility, and increases at the end of each calendar quarter. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 30:432–443, 2010
Noninvasive optical measures of CBV, StO2, CBF index, and rCMRO2 in human premature neonates' brains in the first six weeks of life
Authors: Roche‐Labarbe Nadège , Carp Stefan A. , Surova Andrea , Patel Megha , Boas David A. , Grant P. Ellen , Franceschini Maria Angela 
Published: July 2009

AbstractWith the causes of perinatal brain injuries still unclear and the probable role of hemodynamic instability in their etiology, bedside monitoring of neonatal cerebral hemodynamics with standard values as a function of age are needed. In this study, we combined quantitative frequency domain near infrared spectroscopy (FD‐NIRS) measures of cerebral tissue oxygenation (StO2) and cerebral blood volume (CBV) with diffusion correlation spectroscopy (DCS) measures of a cerebral blood flow index (CBFix) to test the validity of the CBV‐CBF relationship in premature neonates and to estimate cerebral metabolic rate of oxygen (rCMRO2) with or without the CBFix measurement. We measured 11 premature neonates (28–34 weeks gestational age) without known neurological issues, once a week from one to six weeks of age. In nine patients, cerebral blood velocities from the middle cerebral artery were collected by transcranial Doppler (TCD) and compared with DCS values. Results show a steady decrease in StO2 during the first six weeks of life while CBV remains stable, and a steady increase in CBFix. rCMRO2 estimated from FD‐NIRS remains constant but shows wide interindividual variability. rCMRO2 calculated from FD‐NIRS and DCS combined increased by 40% during the first six weeks of life with reduced interindividual variability. TCD and DCS values are positively correlated. In conclusion, FD‐NIRS combined with DCS offers a safe and quantitative bedside method to assess CBV, StO2, CBF, and rCMRO2 in the premature brain, facilitating individual follow‐up and comparison among patients. A stable CBV‐CBF relationship may not be valid for premature neonates. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
Implications of CA3 NMDA and opiate receptors for spatial pattern completion in rats
Authors: Kesner Raymond P. , Warthen Danielle K. 
Published: July 2009

AbstractTheoretical models of the CA3 suggest that because of its architecture, it mediates spatial pattern completion and working memory processes. The aim of this study was to determine whether with the use of drugs to block neurotransmitter action in CA3 one can separate the operation of these two processes using a visual–spatial pattern completion task for multiple cues. Rats were trained on a cheeseboard apparatus with a black curtain containing four extramaze cues. In the study phase rats removed a black block from one of 15 food wells and then after a 10‐ or 30‐s delay in the test phase they had to return to the food well in the absence of the black block. After reaching criterion performance cannulae were bilaterally implanted into the CA3 of the rats. Rats were then given AP5, naloxone, or phosphate buffered saline (PBS) and following the standard study phase they were given the test phase with 0, 1, 2, 3, or 4 cues removed. The mean degree of error in all drugs and all cue conditions was recorded. Overall spatial inaccuracy was recorded in rats under the AP5 30‐s delay condition, whereas deficits were contingent upon the number of cues available under all naloxone conditions. Results show that the blockage of glutamate via AP5 inhibited short‐term or working memory, whereas the blockage of mu‐opioids via naloxone disrupted visual–spatial pattern completion. © 2009 Wiley‐Liss, Inc.
Metabolic activity in the brain of juvenile and adult rats with a neonatal ventral hippocampal lesion
Authors: François Jennifer , Koning Estelle , Ferrandon Arielle , Sandner Guy , Nehlig Astrid 
Published: July 2009

AbstractLongitudinal studies on patients for schizophrenia suggest that functional brain perturbations precede the onset of symptoms. Rats with a neonatal ventral hippocampal lesion (NVHL) are considered as a heuristic neurodevelopmental model of schizophrenia. We characterized basal metabolic changes observed in NVHL rats before and after the age when known behavioral alterations have been reported. Male pups were lesioned with ibotenic acid at postnatal day 7 (PD7). We measured local cerebral metabolic rates for glucose (LCMRglc) by the quantitative autoradiographic [14C]2‐deoxyglucose technique at pre‐ (PD21) and postpubertal (PD42) ages when NVHL rats do not express abnormal dopamine related behaviors, and at adulthood (PD70). We observed a widespread increase in LCMRglcs in PD21 NVHL indicative of an ongoing intense reorganization of the brain while at PD42, increases were less extended. At PD70, changes in glucose metabolism were restricted to specific systems, such as the auditory system, the cerebellum, the serotonergic median raphe, and median septum. These data show in a heuristic animal model of schizophrenia that functional metabolic changes within the brain could precede the onset of dopamine‐related behavioral alterations and lead to a distinct ensemble of functional changes in adulthood in systems that may be relevant to schizophrenia. © 2009 Wiley‐Liss, Inc.
Tubulin targets in the pathobiology and therapy of glioblastoma multiforme. I. class III β‐tubulin
Authors: Katsetos Christos D. , Dráberová Eduarda , Legido Agustin , Dumontet Charles , Dráber Pavel 
Published: July 2009

AbstractGlioblastoma multiforme (GBM) is the most common and deadliest form of primary brain cancer in adults. Despite advances in molecular biology and genetics of gliomas currently there is no effective treatment or promising molecularly targeted experimental therapeutic strategies for these tumors. In previous studies we have shown aberrant overexpression of the class III β‐tubulin isotype (βIII‐tubulin) in GBM and have proposed that this change may reflect perturbations in microtubule dynamics associated with glioma tumorigenesis, tumor progression and malignant transformation into GBM. This minireview focuses on microtubules and tubulin as emerging targets in potential therapy of GBM using a new class of βIII‐tubulin‐targeted drugs in the light of recent developments concerning the function and potential role of this isotype in clinically aggressive tumor behavior, cancer stem cells, tumor hypoxia and chemoresistance to tubulin binding agents, principally taxanes. J. Cell. Physiol. 221: 505–513, 2009. © 2009 Wiley‐Liss, Inc.
Galactosyl derivative of Nω‐nitro‐L‐arginine: Study of antiproliferative activity on human thyroid follicular carcinoma cells
Authors: Melisi Daniela , Rosso Francesco , Curcio Annalisa , Tortora Carla , Nieddu Maria , Marino Gerardo , Lettieri Maria , Grimaldi Anna , Luongo Elvira , Romano Simona , Romano Maria Fiammetta , Boatto Gianpiero , Abignente Enrico , Barbarisi Alfonso , Rimoli Maria Grazia 
Published: July 2009

AbstractThe methyl ester prodrug of Nω‐nitro‐L‐arginine (L‐NAME) has been reported to exert anticancer effects against several human tumors, including thyroid carcinoma, by inhibiting nitric oxide synthase (NOS). However, chronic administration of L‐NAME has often led to adverse events causing cardiovascular alterations due to its potential toxic effect. Here we report for the first time the synthesis of the galactosyl ester prodrug of Nω‐nitro‐L‐arginine, NAGAL, a prodrug capable of inhibiting NOS more efficiently and with fewer adverse events than its parent drug. For this purpose RO82‐W‐1, a thyroid cell line derived from human follicular carcinoma, was used. MTT test results showed that NAGAL affected cell viability to a significantly greater extent than did L‐NAME. Moreover, fluorescence activated cell sorter (FACS) analyses revealed that NAGAL, compared to L‐NAME, was able to reduce nitric oxide (NO) production as well as increase the percentage of apoptotic thyreocytes. Western blot further confirmed the reduction in NOS‐II expression by NAGAL. Finally, by using the LC–MS technique, we found that NAGAL elicited a higher increase in Nω‐nitro‐L‐arginine (NA) concentration than did L‐NAME. Thus, this study suggests that NAGAL could be considered a potential therapeutic tool for those pathologies involving an overproduction of NO, including thyroid carcinoma. J. Cell. Physiol. 221: 440–447, 2009. © 2009 Wiley‐Liss, Inc.
Nano‐scale analysis of graphene layers by tip‐enhanced near‐field Raman spectroscopy
Authors: Saito Yuika , Verma Prabhat , Masui Kyoko , Inouye Yasushi , Kawata Satoshi 
Published: July 2009

AbstractWe demonstrate nano‐scale optical analysis of graphene layers by tip‐enhanced near‐field Raman spectroscopy (TERS). In this technique, the spatial resolution ∼30 nm is realized by the near‐field probe which acts as a nano‐light source. From the intensity change of the Raman band of silicon generated from the near‐field probe, we can conveniently estimate the edge boundaries and the number of stacking layers. TERS measurement across the layer edges reveals the nano‐scale properties of the material as well as the existence of local defects and edge boundaries. The intensity change of the G‐band shows the step‐like behavior that follows the layer boundary, whereas the two components in 2D peak show more complex behaviors even inside layers. The peak fluctuation in the 2D band also suggests the local stress distribution due to interlayer interactions. An excess charge effect is observed through the correlation between the peak position and the width of the G‐band and their nano‐scale distribution within a layer is revealed. Besides the vibrational analysis, we successfully performed the estimation of the number of layers in two‐dimensional imaging by the same experimental platform, which allows us high‐throughput nondestructive identification of graphene layers critical for the evaluation of this material especially in future device applications. Copyright © 2009 John Wiley & Sons, Ltd.
Temperature‐dependent Raman scattering in ferroelectric Bi4−xNdxTi3O12(x = 0, 0.5, 0.85) single crystals
Authors: Liang Kun , Qi Yajun , Lu Chaojing 
Published: July 2009

AbstractThe temperature‐dependent Raman spectra of ferroelectric Bi4−xNdxTi3O12(x = 0, 0.5, 0.85) single crystals were recorded from 100 to 800 K. It was found that there is a critical Nd content x0 between 0.5 and 0.85. The Nd3+ ions prefer to replace Bi3+ ions in pseudo‐perovskite layers when x < x0, while they might begin to incorporate into (Bi2O2)2+ layers when x ≥ x0. Nd substitution leads to a decrease in the ferroelectric–paraelectric transition temperature (Tc). A monoclinic distortion of orthorhombic structure occurs in Bi4Ti3O12 crystals at temperatures below 200 K. Copyright © 2009 John Wiley & Sons, Ltd.
Endoscopic management of Zenker's diverticulum: Stapler assisted versus Harmonic Ace
Authors: Sharp Dawn B. , Newman John R. , Magnuson J. Scott 
Published: July 2009

AbstractObjectives/Hypothesis:Endoscopic repair has become the preferred method of treatment for Zenker's diverticuli. The objective of this study is to compare the endoscopic stapling technique with a novel technique using the Harmonic Ace device (Ethicon Endo‐Surgery, Inc., Cincinnati, OH).Study Design:A retrospective chart review.Methods:Medical records of 48 consecutive patients who underwent endoscopic repair of a Zenker's diverticulum were reviewed. Data were gathered for demographics, symptoms, treatment techniques, and outcomes. Analysis was made using standard statistical methods.Results:A total of 52 endoscopic procedures were attempted and 50 performed: 28 stapler assisted, 20 Harmonic Ace assisted, and 2 using both techniques. Three procedures were aborted due to anatomic limitations. Forty‐four (88%) patients reported complete resolution of their symptoms. Overall, there were six (12%) reported complications. Five (17.9%) complications involved the stapler technique and 1 (5%) using the Harmonic Ace. The difference between these two groups was not significant (P < .38). The average diverticulum size was smaller in the Harmonic Ace group compared to the stapler group (P < .0017). Patients with diverticuli larger than 2 cm were more likely to have postoperative complications than those with smaller ones.Conclusions:Stapler and Harmonic Ace assisted endoscopic repair of Zenker's diverticulum are two safe and effective minimally invasive techniques. Postoperative complications are more likely due to size of the diverticulum and not the device used. The Harmonic Ace used alone or in combination with the stapler may offer additional advantages over conventional open and stapler assisted techniques, addressing size limitations and persistent symptoms. Laryngoscope, 2009
Human papillomavirus reduces the prognostic value of nodal involvement in tonsillar squamous cell carcinomas
Authors: Straetmans Jos M. J. A. A. , Olthof Nadine , Mooren Jeroen J. , de Jong Jos , Speel Ernst‐Jan M. , Kremer Bernd 
Published: July 2009

AbstractObjectives/Hypothesis:Assessment of the prognostic value of nodal status in relation to human papillomavirus (HPV) status and the various treatment modalities in tonsillar squamous cell carcinomas (TSCC).Study Design:Retrospective 5‐year survival analysis.Methods:A 5‐year follow‐up of disease‐free, disease‐specific, and overall survival in a group of 81 patients with TSCC was conducted. The nodal status and integration of HPV‐DNA in the genome (detected with fluorescence in situ hybridization) as prognostic indicators were examined while correcting for other clinical parameters (smoking habits, alcohol consumption, treatment modality, differentiation, TNM classification).Results:Of TSCCs, 41% were positive for HPV type 16. In these TSCCs, the primary tumor was significantly smaller when compared to HVP‐negative TSCCs (P = .04), whereas the percentage of cases with cervical metastases was identical. In the total population, it was not nodal involvement, but rather HPV manifestation, which was related to patient prognosis. Within the treatment modalities (surgery combined with radiotherapy and radiotherapy alone), neither nodal status nor HPV were prognostic indicators.Conclusions:Since a substantial percentage of TSCCs are HPV‐positive and metastasizes to cervical lymph nodes in less advanced primary tumors, the N status is an unreliable prognostic indicator in TSCCs. HPV is only prognostically relevant in the total tumor population, but loses its value within patient groups receiving a single treatment modality. The value of HPV for prognosis of patients with TSCC requires further study. Laryngoscope, 2009