bluuebunny/crossref_metadata_2025_split huggingface dataset:
Towards A,D‐(1,10‐Phenanthroline)‐Bridged Calix[6]arene Dendrimers
Authors: Eggert Jan P. W. , Lüning Ulrich 
Published: November 2007

Abstract5‐Bromo‐2,9‐bis(bromomethyl)‐1,10‐phenanthroline (5) has been synthesized starting from 5‐bromo‐2,9‐dimethyl‐1,10‐phenanthroline (1) in overall yields of up to 53 % by two approaches. Next, calix[6]arene (7) was bridged with 5, giving the A,D‐bridged bimacrocyle 9 in 42 % yield. Under application of Sonogashira reaction conditions, trimethylsilyl‐protected ethyne was first coupled to the 5‐position of the 1,10‐phenanthroline, and the ethyne unit was then deprotected and connected with 1,3,5‐triiodobenzene (12) as a trivalent core. A trimeric first‐generation dendrimer 13 was formed, together with a Glaser dimer sideproduct, and could be isolated in 36 % yield. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis of 3‐Alkynylselenophene Derivatives by a Copper‐Free Sonogashira Cross‐Coupling Reaction
Authors: Alves Diego , dos Reis Joel S. , Luchese Cristiane , Nogueira Cristina W. , Zeni Gilson 
Published: November 2007

Abstract3‐Iodoselenophene derivatives undergo direct Sonogashira cross‐coupling reactions with several terminal alkynes in the presence of a catalytic amount of Pd(PPh3)2Cl2 in DMF with Et3N as the base under cocatalyst‐free conditions. This cross‐coupling reaction proceeded cleanly under mild conditions and was performed with propargylic alcohols and propargylic ethers, as well as alkyl, vinyl and aryl alkynes to furnish the corresponding 3‐alkynylselenophenes in good‐to‐excellent yields.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Pachychalines A–C: Novel 3‐Alkylpyridinium Salts from the Marine Sponge Pachychalina sp.
Authors: Laville Rémi , Thomas Olivier P. , Berrue Fabrice , Reyes Fernando , Amade Philippe 
Published: November 2007

AbstractThree 3‐alkylpyridinium salts, pachychalines A (1), B (2) and C (3), were isolated from the Caribbean marine spongePachychalina sp. (order Haplosclerida). They are the first examples of 3‐(aminoalkyl)pyridinium salts. Their chemical structures were elucidated by NMR spectroscopy and detailed ESI HRMS–MS analysis. The total synthesis of 1 allowed the confirmation of the unusual C–C connection between both pyridinium moieties. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Purported Synthesis of 3,4,7,8‐Tetraphenyl‐1,2,5,6‐tetraazocine from Benzil and Hydrazine: Competing Cyclization and Carbon–Carbon σ‐Bond Scission
Authors: Eisch John J. , Chan Tsz Y. , Gitua John N. 
Published: November 2007

AbstractThe claims that 3,4,7,8‐tetraphenyl‐1,2,5,6‐tetraazocine can be prepared by the thermal condensation of two moles of benzil monohydrazone or of an equimolar mixture of benzil and benzil dihydrazone have been thoroughly reinvestigated. When such thermolyses were conducted in moist air, neither the claimed 3,4,7,8‐tetraphenyl‐1,2,5,6‐tetraazocine nor the precedented isomeric tetraazapentalene derivative was detected. The following products were unambiguously formed from the heating of molten benzil monohydrazone (%): benzil (10), benzaldehyde (10), benzamide (22), benzyl phenyl ketone (19), benzil bis(ketazine) (11), 3,4,5,6‐tetraphenylpyridazine (9), benzil benzaldehyde azine (10), and, after column chromatography, 2,4,5‐triphenylimidazole (2). This last component had a melting point and the fluorescent properties in UV light attributed by the original investigator to the mistakenly presumed 3,4,7,8‐tetraphenyl‐1,2,5,6‐tetraazocine. Thus, the original claims for the synthesis of such a novel tetraazocine ring or even for the synthesis of the precedented isomeric zwitterionic tetraazapentalene have now been repudiated. The formation of 2,4,5‐triphenylimidazole as a side reaction in the thermolysis of benzil monohydrazone can readily be rationalized as arising from benzil, benzaldehyde, and a source of ammonia, namely, benzamide, in the long‐known Radziszewski reaction. Corroborating evidence was provided by data from the thermolysis of benzil dihydrazone. In addition, the origin of other side products is explained in terms of other possible condensations. Finally, preliminary experiments on using irreversible dehydrating agents such as titanium(IV) isopropoxide with benzil monohydrazone indicate that 3,4,7,8‐tetraphenyl‐1,2,5,6‐tetraazocine is formed at room temperature as a transitory intermediate, which eliminates dinitrogen to produce 3,4,5,6‐tetraphenylpyridazine.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
2‐DE and MALDI‐TOF‐MS for a comparative analysis of proteins expressed in different cellular models of amyotrophic lateral sclerosis
Authors: Di Poto Cristina , Iadarola Paolo , Bardoni Anna Maria , Passadore Ileana , Giorgetti Sofia , Cereda Cristina , Carrì Maria Teresa , Ceroni Mauro , Salvini Roberta 
Published: November 2007

AbstractAmyotrophic lateral sclerosis (ALS) is a fatal, neurodegenerative disorder characterized by the selective loss of motor neurons from the spinal cord and brain. About 10% of ALS cases are familial (FALS), and in 20% of these cases the disease has been linked to mutations in the Cu,Zn‐SOD1 gene. Although the molecular mechanisms causing these forms of ALS are still unclear, evidence has been provided that motor neurons injuries associated with mutant superoxide dismutase (SOD1)‐related FALS result from a toxic gain‐in‐fuction of the mutated enzyme. To understand better the role of these mutations in the pathophysiology of FALS we have compared the pattern of proteins expressed in human neuroblastoma SH‐SY5Y cell line with those of cell lines transfected with plasmids expressing the wild‐type human SOD1 and the H46R and G93A mutants. 2‐DE coupled to MALDI‐TOF‐MS were the proteomic tools used for identification of differentially expressed proteins. These included cytoskeletal proteins, proteins that regulate energetic metabolism and intracellular redox conditions, and the ubiquitin proteasome system. The proteomic approach allowed to expand the knowledge on the pattern of proteins, with altered expression, which we should focus on, for a better understanding of the possible mechanism involved in mutated‐SOD1 toxicity. The cellular models considered in this work have also evidenced biochemical characteristics common to other SOD1‐mutated cellular lines connected to the pathogenesis of ALS.
Protein microchips in biomedicine and biomarker discovery
Authors: Spisak Sandor , Tulassay Zsolt , Molnar Bela , Guttman Andras 
Published: November 2007

AbstractProtein microarray technology is of high recent interest, especially for generating confirmatory and complementary information for transcriptomic studies. In this paper, the advantages, technical limitations, main application fields, and some early results of protein microarrays are reviewed. Today protein microchip technology is mostly available in the form of printed glass slides, bioaffinity surfaces, and tissue microarray (TMA)‐based techniques. The advantages of glass slide‐based microchips are the simplicity of their application and their relatively low cost. Affinity surface‐based protein chip techniques are applicable to minute amounts of starting material (<1 μg), but interrogation of these chips requires expensive instrumentation, such as mass spectrometers. TMAs are useful for parallel testing of antibody specificities on a broad range of histological specimens in a single slide. Protein microarrays have been successfully implemented for serum tumor marker profiling, cell physiology studies, and mRNA expression study verification. Some of the bottlenecks of the technology are protein instability, problems with nonspecific interactions, and the lack of amplification techniques to generate sufficient amounts of the lower abundance proteins. In spite of the current difficulties, protein microchips are envisioned to be available for routine biomedical and diagnostic applications provided that the ongoing technological developments are successful in improving sensitivity, specificity, and reducing costs.
Vertical dispersion of dust particles in a turbulent boundary layer
Authors: Wang H. T. , Zhou Y. H. , Dong Z. B. , Ayrault M. 
Published: November 2007

AbstractThe flow of glass dust particles in air was investigated experimentally over a flat bed in a wind tunnel. Particle concentrations were measured by light scattering diffusion (LSD) and digital image processing. It was verified that saltation is the main mechanism for ejection of dust particles. Vertical mean dust concentrations for ‘pure dust’ and two mixtures of dust and saltating glass particles were determined and analysed. The experiments confirmed that for the ‘pure dust’ configuration the mean concentration decreases as a power function with height. For the mixture configurations and for free stream velocities close to the threshold velocity, the mean concentration also decreases in a power function. For higher velocities, mean concentration decreases respectively as a power function or exponential function for large and small ratios of the dust:saltating particles respectively. The exponent of the power law reflects the dust:particle ratio and the free stream flow velocity. Copyright © 2007 John Wiley & Sons, Ltd.
Seasonal evolution of runoff generation on agricultural land in the Belgian loess belt and implications for muddy flood triggering
Authors: Evrard Olivier , Vandaele Karel , Bielders Charles , Wesemael Bas van 
Published: November 2007

AbstractMuddy floods due to agricultural runoff are a widespread and frequent phenomenon in the European loess belt, and particularly in central Belgium. These floods are triggered when high quantities of runoff are generated on cropland and cause severe erosion. Three soil surface characteristics are relevant to determine the runoff potential of cultivated soils: soil cover by crops and residues, soil surface crusting and roughness. These characteristics have been observed on 65 cultivated fields throughout 2005. A heavy rainfall event representative for events triggering muddy floods in the region (60 mm h−1 during 30 minutes) has been simulated using a 0·5 m2 simulator on fields with the 17 most observed combinations of soil surface characteristics in central Belgium. Runoff is not observed in the case of (ploughed) bare uncrusted soils, nor in the case of soils covered by crops showing a transitional crust and a moderate roughness (1–2 cm). In the cases where runoff has been observed, mean runoff coefficients ranged from 13% (wheat in July) to 58% (sugar beet or maize in May and June). Grassed buffer strips (GBSs) and grassed waterways (GWWs) show a higher runoff coefficient (62% for GBSs and 73% for GWWs) than most cultivated soils (13–58%). Furthermore, it is demonstrated that small plot measurements can be used to estimate runoff generation at the field scale. A classification of runoff generation risk based on the surveys of soil surface characteristics has been applied to common crops of central Belgium. February as well as the period between May and September are the most critical for runoff at the field scale. However, it appears from monitoring of a 16 ha catchment that the highest runoff volumes and peak discharges are recorded between May and August after heavy rainfall, explaining why 85% of muddy floods are recorded during this period in central Belgium. Copyright © 2007 John Wiley & Sons, Ltd.
Hybrid automatic voltage control strategy and its application to Northeast China 500 kV power grid
Authors: Mei Shengwei , Xie Bangpeng , Che Wenyan , Wang Zhitao 
Published: November 2007

AbstractThis paper introduces an integrated control strategy based on hybrid control theory for the control of voltage and reactive power in power system substations. The strategy adopts a hierarchical, multilayer structure to achieve a multi‐objective optimization of voltage and reactive power control and improves the traditional “nine‐area diagram” control method. The new hybrid control strategy not only solves the problem of oscillatory responses caused by the changes of the on‐load tap changer (OLTC) taps and switching the shunt capacitors, but also responds to the global optimal control commands of voltage and reactive power from the master station with good steady‐state responses. The hybrid automatic voltage control (HAVC) strategy is tested via simulation of the Northeast China 500 kV grid and the results demonstrate the effectiveness of the strategy. Copyright © 2007 John Wiley & Sons, Ltd.
White matter vascular lesions are related to parietal‐to‐frontal coupling of EEG rhythms in mild cognitive impairment
Authors: Babiloni Claudio , Frisoni Giovanni B. , Pievani Michela , Vecchio Fabrizio , Infarinato Francesco , Geroldi Cristina , Salinari Serenella , Ferri Raffaele , Fracassi Claudia , Eusebi Fabrizio , Rossini Paolo M. 
Published: November 2007

AbstractDo cerebrovascular and Alzheimer's disease (AD) lesions represent additive factors in the development of mild cognitive impairment (MCI) as a putative preclinical stage of AD? Here we tested the hypothesis that directionality of fronto‐parietal functional coupling of electroencephalographic (EEG) rhythms is relatively preserved in amnesic MCI subjects in whom the cognitive decline is mainly explained by white‐matter vascular load. Resting EEG was recorded in 40 healthy elderly (Nold) and 78 amnesic MCI. In the MCI subjects, white‐matter vascular load was quantified based on magnetic resonance images (0–30 visual rating scale). EEG rhythms of interest were δ (2–4 Hz), θ (4–8 Hz), α1 (8–10.5 Hz), α2 (10.5–13 Hz), β1 (13–20 Hz), and β2 (20–30 Hz). Directionality of fronto‐parietal functional coupling of EEG rhythms was estimated by directed transfer function software. As main results, (i) fronto‐parietal functional coupling of EEG rhythms was higher in magnitude in the Nold than in the MCI subjects; (ii) more interestingly, that coupling was higher at θ, α1, α2, and β1 in MCI V+ (high vascular load;N= 42; MMSE = 26) than in MCI V− group (low vascular load;N= 36; MMSE= 26.7). These results are interpreted as supporting the additive model according to which MCI state would result from the combination of cerebrovascular and neurodegenerative lesions. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Simultaneous EMG‐functional MRI recordings can directly relate hyperkinetic movements to brain activity
Authors: van Rootselaar Anne‐Fleur , Maurits Natasha M. , Renken Remco , Koelman Johannes H.T.M. , Hoogduin Johannes M. , Leenders Klaus L. , Tijssen Marina A.J. 
Published: November 2007

AbstractObjective:To apply and validate the use of electromyogram (EMG) recorded during functional magnetic resonance imaging (fMRI) in patients with movement disorders, to directly relate involuntary movements to brain activity.Methods:Eight “familial cortical myoclonic tremor with epilepsy” (FCMTE) patients, with tremor‐like cortical myoclonus and cerebellar Purkinje cell degeneration, and nine healthy controls performed hand posture and movement in an on/off fashion (block design). Superfluous movements were quantified as deviations in EMG power, positive and negative, with respect to the average EMG per session. This measure, “residual EMG” (r‐EMG), was derived by Gram–Schmidt orthogonalization. Activation maps resulting from conventional block regressors and novel r‐EMG regressors were compared.Results:In healthy participants, the block posture regressor identified mainly cerebellar activity and some activity in other areas belonging to motor circuitry. In FCMTE patients, no cerebellar activity was seen with the block posture regressor, compatible with cerebellar Purkinje cell changes in FCMTE. EMG power showed little variation during posture in healthy controls. Therefore, the r‐EMG regressor was almost constant and revealed no brain activity as expected. In contrast, in FCMTE patients the r‐EMG posture regressor was highly variable due to continuous myoclonic jerks. It identified sensorimotor cortical areas, compatible with cortical hyperexcitability in FCMTE patients.Conclusion:Conventional block regressors can be used to identify neuronal circuitry associated with a specific motor task, whereas r‐EMG regressors can help identify brain activation directly related to involuntary movements. Simultaneous EMG‐fMRI is complementary to conventional fMRI and will facilitate studies of hyperkinetic movement disorders. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Validation of a fully automated hippocampal segmentation method on patients with dementia
Authors: Firbank Michael J. , Barber Robert , Burton Emma J. , O'Brien John T. 
Published: November 2007

AbstractWe describe a fully automated method for hippocampal segmentation. The method uses SPM5 (http://www.fil.ion.ucl.ac.uk/spm/) software to segment the brain into grey/white matter, and spatially normalize the images to standard space. Grey matter pixels within a predefined hippocampal region in standard space are identified to segment the hippocampi. The method was validated on 36 subjects (9 each of Alzheimer's disease, dementia with Lewy bodies, vascular dementia, and healthy controls). The mean absolute difference in volume compared with manual segmentation was 11% (SD 9%). Linear regression between manual and automated volume gave V(auto) = V(manual) × 0.83 + 401 ml. The method provides an acceptable automated alternative to manual segmentation which may be of value in large studies. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Integrated local correlation: A new measure of local coherence in fMRI data
Authors: Deshpande Gopikrishna , LaConte Stephen , Peltier Scott , Hu Xiaoping 
Published: November 2007

AbstractThis article introduces the measure of integrated local correlation (ILC) for assessing local coherence in the brain using functional magnetic resonance imaging (fMRI) data and characterizes the measure in terms of reproducibility, the effect of physiological noise, and the dependence on image resolution. The coupling of local neuronal processes influences coherence in a voxel's neighborhood. ILC is defined, for each voxel, as the integration of its spatial correlation function. This integrated measure does not require the specification of a neighborhood and, as demonstrated by experimental data, is effectively independent of image resolution. Respiratory and cardiac fluctuations do not considerably alter the ILC value except in isolated areas in and surrounding large vessels. With resting‐state fMRI data, ILC was demonstrated to be tissue‐specific, higher in gray matter than white matter, and reproducible across consecutive runs in healthy individuals. Within the gray matter, ILC was found to be higher in the default mode network, particularly the posterior and anterior cingulate cortices. Comparing ILC maps obtained from resting state and continuous motor task data, we observed reduced local coherence in the default mode network during the task. Finally, we compared ILC and regional homogeneity by examining their ability to discriminate between gray and white matters in resting state data and found ILC to be more sensitive. Hum Brain Mapp 2009. © 2007 Wiley‐Liss, Inc.
Time‐dependent hemispheric shift of the cortical control of volitional swallowing
Authors: Teismann Inga K. , Dziewas Rainer , Steinstraeter Olaf , Pantev Christo 
Published: November 2007

AbstractAn important part of the cortical processing of swallowing takes place in the sensorimotor cortex, predominantly in the left hemisphere. However, until now, only deglutition related brain activation with low time resolution exceeding a time interval of 1 s has been reported. In this study, we have examined the chronological sequence of cortical swallowing processing in humans by means of high temporal resolution magnetoencephalography (MEG). The cortical MEG activity was recorded during self‐paced volitional swallowing in 10 healthy subjects. Data were analyzed using synthetic aperture magnetometry and the group analysis was performed using a permutation test. Swallowing‐related muscle activity was recorded by electromyography. Within the time interval of 1 s of the most pronounced muscular swallowing execution, the MEG analysis revealed neural activation in the primary sensorimotor cortex. During the first 600 ms, only left hemispheric activation was found, bihemispheric activation during the next 200 ms and a right hemispheric activation during the last 200 ms. Thus, our results demonstrate a time‐dependent shift of neural activation from left to right sensorimotor cortex during deglutition with left hemispheric dominance in the early stage of volitional swallowing and right hemispheric dominance during its later part. Hum Brain Mapp 2009. © 2007 Wiley‐Liss, Inc.
Response to paclitaxel in adenoid cystic carcinoma of the salivary glands
Authors: Till Brian G. , Martins Renato G. 
Published: November 2007

AbstractBackground.Paclitaxel is not considered to be an active drug in adenoid cystic carcinoma (ACC) of the salivary glands. We report 2 consecutive cases of patients with ACC who responded to paclitaxel.Methods.The patients were: (1) a 58‐year‐old man with recurrent ACC who developed pulmonary metastases, had progressive disease after a good response to first‐line chemotherapy, and then achieved a partial response to weekly single‐ agent paclitaxel; and (2) a 46‐year‐old woman with extensive thoracic ACC metastases who achieved a significant response after 2 cycles of paclitaxel chemotherapy.Results.The first patient died of progressive disease approximately 4 months after completing paclitaxel therapy, and the second patient had disease control after 6 cycles of paclitaxel.Conclusions.Systemic weekly paclitaxel produced a significant response in 2 patients with ACC of the head and neck, and its use in this disease merits further study. © 2007 Wiley Periodicals, Inc. Head Neck, 2008
Submucosal purse‐string suture as a treatment of leakage around the indwelling voice prosthesis
Authors: Jacobs Kristien , Delaere Pierre R. , Poorten Vincent L. M. Vander 
Published: November 2007

AbstractBackground.Leakage around the indwelling voice prosthesis is an annoying complication of tracheoesophageal speech.Methods.Twenty patients, who experienced peripheral leakage of the tracheoesophageal fistula, were treated with a purse‐string suture. Our aim was to get the patients free of leakage without losing their voice prosthesis. The technique was considered successful if this objective was reached and unsuccessful if eventually closure of the fistula was required.Results.Immediately after the procedure, no patients showed residual leakage. At 1 month, 2 patients experienced recurrent leakage. At a mean follow‐up of 19.4 months, the method was successful in 16 patients and unsuccessful in 4 patients.Conclusions.If peripheral leakage is not amenable to simple downsizing of the indwelling voice prosthesis, we feel the purse‐string suture is the first‐choice treatment because of its safety, efficiency, low cost, and ease of application. © 2007 Wiley Periodicals, Inc. Head Neck, 2008