bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrochemical Sensors Based on Architectural Diversity of the π‐Conjugated Structure: Recent Advancements from Conducting Polymers and Carbon Nanotubes
Authors: Dai Liming
Published: September 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Are MAP Kinases Drug Targets? Yes, but Difficult Ones
Authors: Margutti Simona , Laufer Stefan A.
Published: September 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Deep Non‐Invasive Raman Spectroscopy of Living Tissue and Powders
Authors: Matousek Pavel
Published: September 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Filtration
Authors: Chase George G. , Mayer Ernest
Published: September 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Optical Spectroscopy and Theoretical Studies in Calixarene Chemistry
Authors: Mohammed‐Ziegler Ildiko , Billes Ferenc
Published: September 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
State criterion of wind turbine generator operation using tower shadow effect (Part 2)
Authors: Naitoh Tadashi , Satoh Kohki , Takada Hiroki , Yoshida Suguru , Abe Hidefumi , Suzuki Hirokazu , Fujiwara Nobuyuki
Published: September 2007

In order to obtain wind energy effectively, the pole‐change‐type induction generators are used as the wind turbine generators. Otherwise, the pole‐change‐type induction generator causes the voltage dips at pole changing time. To maintain the power quality, it is important to know the state change of the generator operation. Therefore, the authors have studied a state criterion of generator using the tower shadow effect, which is the active power oscillation caused by a rotation torque drop when the tower and the turbine blade overlap each other.

In this paper, an improved identification method of oscillation frequency, which is the criterion of wind turbine generator operation, is proposed. The proposed method is applied to measured data and good results are obtained. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 25–31, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20395
FDTD analysis of switching characteristics in magnetooptic functional devices using magnetostatic surface waves
Authors: Noguchi Atsushi , Goto Nobuo , Miyazaki Yasumitsu
Published: September 2007

Collinear magnetooptic interaction with magnetostatic surface waves (MSSW) can be used for wavelength‐selective switches, wavelength filters, and frequency shifters in wavelength‐division‐multiplexed (WDM) photonic networks and optical processing systems. The switching efficiency can be improved with a multilayer waveguide structure. To investigate the dynamic switching characteristics, the FDTD method was employed. The mode conversion between TE and TM mode was successfully demonstrated with FDTD simulation. The filtering characteristics were also evaluated. The FDTD results were compared with the result from the coupled mode theory, and good agreement was obtained. Switching of an optical pulse was also demonstrated by the FDTD method. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 40–47, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20501
Short‐span seeking control of hard disk drive with vibration suppression PTC
Authors: Fukushima Keisuke , Fujimoto Hiroshi , Nakagawa Shinsuke
Published: September 2007

In a short‐span seeking‐mode of hard disk drives, the resonance modes are getting crucial obstruction to meet the demand on high‐speed data access. In this paper, a novel vibration suppression perfect tracking control (PTC) method is proposed based on controllable canonical realization. In the proposed method, it is assumed that the plant is modeled as the rigid and primary resonance mode. By using this model, the feed forward controller is designed with PTC by multirate sampling control in order to suppress the primary vibration. Additionally, the higher‐order resonance vibration is attenuated by using the trajectory MHVT. The proposed method achieved 16% faster seeking than MPVT, a conventional method. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 66–72, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20546
Tensions between Scottish National Policies for onshore wind energy and local dissatisfaction – insights from regulation theory
Authors: Parkhill Karen
Published: September 2007

Although best described as a ‘meta’ theory addressing the endurance of capitalism, regulation theory can successfully be used to explore not only the economic dimensions, but also the political, socio‐cultural and environmental dimensions of particular developmental strategies. Thus, it offers a framework for embedding abstract debates about social attitudes to new technologies within debates about ‘real regulation’ – the economic, social and cultural relationships operating through particular places. This paper uses regulation theory and qualitative, interview‐based data to analyse Scotland's drive for onshore wind energy. This approach teases out how responses to wind farms are bound up with wider debates about how rural spaces are, and should be, regulated; the tensions within and between national political objectives, local political objectives and local communities' dissatisfaction; and the connections between local actors and more formal dimensions of renewable energy policy. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment.
Adsorptive Stripping Voltammetric Determination of Ultra Trace of Zinc and Lead with Carbidopa as Complexing Agent in Food and Water Samples
Authors: Gholivand M. B. , Ahmadi F. , Sohrabi A.
Published: September 2007

In the present work, the cathodic stripping voltammetric methodology using a hanging mercury drop electrode was described for simultaneous determination of lead and zinc in different real samples. The method is based on adsorption of metal ions on mercury electrode using carbidopa as a suitable complexing agent. The potential was scanned to the negative direction and the differential pulse stripping voltammograms were recorded. Optimal conditions were found to be: accumulation time; 70 s, accumulation potential; 50 mV versus Ag/AgCl, scan rate; 40 mV s−1, supporting electrolyte; 0.01 M ammonia buffer at pH 8.5, and concentration of carbidopa; 8.0 μM. The relationship between the peak current versus concentration was linear over the range of 0.1–210 and 0.2–170 nM for lead and zinc, respectively. The detection limits are 0.09 and 0.15 nM for lead and zinc ions respectively. The relative standard deviations at a concentration level of 70 nM of both metal ions are found 1.08 and 1.24% for lead and zinc ions respectively.
A Cobalt Film Electrode for Nitrite Determination in Natural Water
Authors: Soropogui Koïkoï , Sigaud Monique , Vittori Olivier
Published: September 2007

In this study a cobalt film electrodeposited on a copper disk (Ø=3.1 mm) was tested as electrode to measure nitrite ions in raw water. This electrode was able to determine the nitrite ions concentration in nondeaerated synthetic media and in natural water. The electrode reached a detection limit of 0.2 μmol L−1 and has a linear concentration range of 0.4 to 2 μmol L−1 NO2−. The influence of several ions such as NO3−, Cl−, SO42−, Mg2+, HCO3− and NH4+ was also tested. The electrode was used to determine the concentration of nitrite ions in a real sample.
Gold Nanoparticle‐Based Redox Signal Enhancement for Sensitive Detection of Human Chorionic Gonadotropin Hormone
Authors: Idegami Koutarou , Chikae Miyuki , Kerman Kagan , Nagatani Naoki , Yuhi Teruko , Endo Tatsuro , Tamiya Eiichi
Published: September 2007

A sensitive immunosensor for the detection of pregnancy marker, human chorionic gonadotropin hormone (hCG), was developed using the direct electrical detection of Au nanoparticles. We utilized disposable screen‐printed carbon strips (SPCSs) for the development of our immunosensor, which provided cost‐effective tests with the required antigen sample volume as small as 2 μL. After the recognition reaction between the surface‐immobilized primary antibody and hCG, the captured antigen was sandwiched with a secondary antibody that was labeled with Au nanoparticles. Au nanoparticles were exposed to a preoxidation process at 1.2 V for 40 s, which was subsequently followed with a reduction scan on the same surface using differential pulse voltammetry (DPV). We could observe Au nanoparticle‐labeled antigen‐antibody complexes immobilized on the surface of SPCS using scanning electron microscopy (SEM). Additionally, the number of Au nanoparticles on the immunosensor was determined using SEM images, and showed a linear relationship with the current intensity obtained from the DPV measurements with a detection limit of 36 pg/mL hCG (612 fM, 3.6×10−4 IU/mL). Our immunosensor system, a combination of the screen‐printing technology with Au nanoparticles provides a promising biosensor for various applications in life sciences.
Functional estimation of spatiotemporal heterogeneities
Authors: Ruiz‐Medina María D. , Angulo José M.
Published: September 2007

Heterogeneity analysis is one of the most complex concerns in spatiotemporal statistics, due to the different sources of variability present in real phenomena. In this paper, a functional approximation to the multiscale structure of a certain class of non‐homogeneous (non‐stationary) spatiotemporal processes, based on a multiple‐window atomic decomposition, is studied. The multiscaling exponent, defining the local regularity and correlation of the processes, is estimated from such a decomposition. Copyright © 2007 John Wiley & Sons, Ltd.
Extent of surgery in the management of locally advanced sinonasal malignancies
Authors: Resto Vicente A. , Chan Annie W. , Deschler Daniel G. , Lin Derrick T.
Published: September 2007

Background.

The relative importance of surgery within multimodality regimens commonly used to treat advanced sinonasal malignancies remains unknown.

Methods.

One hundred two patients with locally advanced sinonasal cancers treated with proton beam radiation therapy with or without surgery were retrospectively reviewed. Extent of surgery and outcome variables of local control, disease‐free survival, and overall survival were evaluated. Patterns of failure were also assessed.

Results.

Extent of surgery correlated with disease‐free survival and overall survival rates. Local control rate, however, was independent of the degree of surgical resection achieved. Overall, treatment failure most commonly resulted from distant metastases, which occurred in 30% of patients and also correlated with extent of surgical resection. Tumor type‐specific outcomes reveal differences associated with the extent of surgery achieved.

Conclusion.

High‐dose radiotherapy with proton beam resulted in excellent local control rates in patients with locally advanced sinonasal cancer, irrespective of the extent of surgery. Complete resection, however, was predictive of improved disease‐free survival and decreased rate of distant metastasis. © 2007 Wiley Periodicals, Inc. Head Neck, 2008
Sphingosine 1‐phosphate induces EGFR expression via Akt/NF‐κB and ERK/AP‐1 pathways in rat vascular smooth muscle cells
Authors: Hsieh Hsi‐Lung , Sun Chi‐Chin , Wu Chou‐Bing , Wu Cheng‐Ying , Tung Wei‐Hsuan , Wang Hui‐Hsin , Yang Chuen‐Mao
Published: September 2007

Sphingosine 1‐phosphate (S1P) has been shown to regulate expression of several genes in vascular smooth muscle cells (VSMCs) and contributes to arteriosclerosis. However, the mechanisms regulating epidermal growth factor receptor (EGFR) expression by S1P in aortic VSMCs remain unclear. Western blotting and RT‐PCR analyses showed that S1P induced EGFR mRNA and protein expression in a time‐ and concentration‐dependent manner, which was attenuated by inhibitors of MEK1/2 (U0126) and phosphatidylinositide 3‐kinase (PI3K; wortmannin), and transfection with dominant negative mutants of ERK and Akt, respectively. These results suggested that S1P‐induced EGFR expression was mediated through p42/p44 MAPK and PI3K/Akt pathways in VSMCs. In accordance with these findings, S1P stimulated phosphorylation of p42/p44 MAPK and Akt which was attenuated by U0126 and wortmannin, respectively. Furthermore, S1P‐induced EGFR upregulation was blocked by a selective NF‐κB inhibitor helenalin. Immunofluorescent staining and reporter gene assay revealed that S1P‐induced activation of NF‐κB was blocked by wortmannin, but not by U0126, suggesting that activation of NF‐κB was mediated through PI3K/Akt. Moreover, S1P‐induced EGFR expression was inhibited by an AP‐1 inhibitor curcumin and tanshinone IIA. S1P‐stimulated AP‐1 subunits (c‐Jun and c‐Fos mRNA) expression was attenuated by U0126 and wortmannin, suggesting that MEK and PI3K/ERK cascade linking to AP‐1 was involved in EGFR expression. Upregulation of EGFR by S1P may exert a phenotype modulation of VSMCs. This hypothesis was supported by pretreatment with AG1478 or transfection with shRNA of EGFR that attenuated EGF‐stimulated proliferation of VSMCs pretreated with S1P, determined by XTT assay. These results demonstrated that in VSMCs, activation of Akt/NF‐κB and ERK/AP‐1 pathways independently regulated S1P‐induced EGFR expression in VSMCs. Understanding the mechanisms involved in S1P‐induced EGFR expression on VSMCs may provide potential therapeutic targets in the treatment of arteriosclerosis. J. Cell. Biochem. 103: 1732–1746, 2008. © 2007 Wiley‐Liss, Inc.
QUILD: QUantum‐regions interconnected by local descriptions
Authors: Swart Marcel , Bickelhaupt F. Matthias
Published: September 2007

A new program for multilevel (QM/QM and/or QM/MM) approaches is presented that is able to combine different computational descriptions for different regions in a transparent and flexible manner. This program, designated QUILD (for QUantum‐regions Interconnected by Local Descriptions), uses adapted delocalized coordinates (Int J Quantum Chem 2006, 106, 2536) for efficient geometry optimizations of equilibrium and transition‐state structures, where both weak and strong coordinates may be present. The Amsterdam Density Functional (ADF) program is used for providing density functional theory and MM energies and gradients, while an interface to the ORCA program is available for including RHF, MP2, or semiempirical descriptions. The QUILD optimization setup reduces the number of geometry steps needed for the Baker test‐set of 30 organic molecules by ∼30% and for a weakly‐bound test‐set of 18 molecules by ∼75% compared with the old‐style optimizer in ADF, i.e., a speedup of roughly a factor four. We report two examples of using geometry optimizations with numerical gradients, for spin‐orbit relativistic ZORA and for excited‐state geometries. Finally, we show examples of its multilevel capabilities for a number of systems, including the multilevel boundary region of amino acid residues, an SN2 reaction in the gas‐phase and in solvent, and a DNA duplex. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Application of microscopy in authentication of traditional Tibetan medicinal plant Halenia elliptica
Authors: Li Jie , Yi Tao , Lai Hong‐Shan , Xue Dan , Jiang Hai , Peng Huan‐Chao , Zhang Hao
Published: September 2007

Halenia elliptica D. Don, a popularly used ethnodrug from Qinghai‐Tibetan plateau, was studied to reveal the indispensable morphoanatomic details. The fixed, sectioned, and stained plant materials as well as the epidermis, powder, and maceration materials were studied using light microscope according to the usual microscopic techniques. The results of the microscopic features were systematic described and illustrated. In the root, an endodermal cell was divided into 8‐16‐22 and 38‐50‐62 daughter cells in transverse section and in face view, respectively, and 9‐11‐13 phloem strands were present in primary structure; in the stem, stone cells were observed in the cortex, pericycle, and external phloem while 17‐19‐21 internal phloem strands were present in an incontinuous ring; in the pedicel, 8‐10‐12 internal phloem strands were observed to form an incontinuous ring; anisocytic and anomocytic stomata were present in leaf and sepal epidermis; pollen grain was with three germinal apertures and furrows; a few tracheids, a large number of spiral vessels, and various fibers were observed. Also, semiquantitative and quantitative micrographic parameter tables were simultaneously presented. Further, the key authentication parameters were concluded. The study indicated that light microscopy and related techniques could be unambiguously applied to the authentication of Halenia elliptica. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
High‐speed atomic force microscopy for observing dynamic biomolecular processes
Authors: Ando Toshio , Uchihashi Takayuki , Kodera Noriyuki , Yamamoto Daisuke , Taniguchi Masaaki , Miyagi Atsushi , Yamashita Hayato
Published: September 2007

The atomic force microscope (AFM) is unique in its capability to capture high‐resolution images of biological samples in liquids. This capability will become more valuable to biological sciences if AFM additionally acquires an ability of high‐speed imaging, because ‘direct and real‐time visualization’ is a straightforward and powerful means to understand biomolecular processes. With conventional AFMs, it takes more than a minute to capture an image, while biomolecular processes generally occur on a millisecond timescale or less. In order to fill this large gap, various efforts have been carried out in the past decade. Here, we review these past efforts, describe the current state of the capability and limitations of high‐speed AFM, and discuss possibilities that may break the limitations and lead to the development of a truly useful high‐speed AFM for biological sciences. Copyright © 2007 John Wiley & Sons, Ltd.
Electrospray ionization mass spectrometry monitoring of indigo carmine degradation by advanced oxidative processes
Authors: Dalmázio Ilza , de Urzedo Ana P. F. M. , Alves Tania M. A. , Catharino Rodrigo R. , Eberlin Marcos N. , Nascentes Clésia C. , Augusti Rodinei
Published: September 2007

The degradation of the dye indigo carmine in aqueous solution induced by two oxidative processes (H2O2/iodide and O3) was investigated. The reactions were monitored by electrospray ionization mass spectrometry in the negative ion mode, ESI(−)‐MS, and the intermediates and oxidation products characterized by ESI(−)‐MS/MS. Both oxidative systems showed to be highly efficient in removing the color of the dye aqueous solutions. In the ESI(−)‐MS of the indigo carmine solution treated with H2O2 and H2O2/iodide, the presence of the ions of m/z 210 (indigo carmine in its anionic form, 1), 216, 226, 235, and 244 was noticeable. The anion of m/z 235 was proposed to be the unprecedented hydroperoxide intermediate 2 formed in solution via an electrophilic attack by hydroxyl and hydroperoxyl radicals of the exocyclic CC bond of 1. This intermediate was suggested to be rapidly converted into the anionic forms of 2,3‐dioxo‐1H‐indole‐5‐sulfonic acid (3, m/z 226), 2‐amino‐α‐oxo‐5‐sulfo‐benzeneacetic acid (4, m/z 244), and 2‐amino‐5‐sulfo‐benzoic acid (5, m/z 216). In the ESI(−)‐MS of the indigo carmine solution treated with O3, two main anions were detected: m/z 216 (5) and 244 (4). Both products were proposed to be produced via an unstable ozonide intermediate. Other anions in this ESI(−) mass spectrum were attributed to be [4 − H + Na]− of m/z 266, [4 − H]2− of m/z 121.5, and [5 − H]2− of m/z 107.5. ESI‐MS/MS data were consistent with the proposed structures for the anionic products 2–5. Copyright © 2007 John Wiley & Sons, Ltd.
Fragmentation of diketopiperazines from Aspergillus fumigatus by electrospray ionization tandem mass spectrometry (ESI‐MS/MS)
Authors: Furtado Niege A. J. C. , Vessecchi Ricardo , Tomaz José Carlos , Galembeck Sérgio E. , Bastos Jairo K. , Lopes Norberto P. , Crotti Antonio E. M.
Published: September 2007

Diketopiperazines (DKPs) corresponding to cyclic dipeptides have been reported to exhibit antimicrobial, antitumor, antimutagenic and antiviral properties. These compounds are commonly isolated from microorganisms and sponges and from a variety of tissues and body fluids. In this work, we used electrospray ionization tandem mass spectrometry (ESI‐MS/MS) to investigate the fragmentation of a series of DKPs previously isolated from Aspergillus fumigatus, which exhibit the same structural core. Loss of CO directly from the protonated molecule was found to be a fragmentation process common to all the compounds analyzed. However, our results revealed a series of ions that are diagnostic for the substituents at C(4) and C(9). In order to rationalize the differences in the fragmentation pathways of substituted and nonsubstituted DKPs, the relative Gibbs energies (ΔG) of the product ions and intermediate ions were estimated using the B3LYP/6–31 + + G(d,p) model. The data reported here can be used for the structural elucidation of DKPs from low sample amounts, as an alternative to NMR. Copyright © 2007 John Wiley & Sons, Ltd.
Secondary ion emission induced by fission fragment impact in CONH3 and CONH3H2O ices: modification in the CONH3 ice structure
Authors: Martinez R. , Farenzena L. S. , Iza P. , Ponciano C. R. , Homem M. G. P. , de Brito A. Naves , Wien K. , da Silveira E. F.
Published: September 2007

CONH3 and CONH3–H2O ices at 25–130 K were bombarded by 252Cf fission fragments (∼65 MeV at the target surface) and the emitted secondary ions were analyzed by time‐of‐flight mass spectrometry (TOF‐SIMS). It is observed that the mass spectra obtained from both ices have similar patterns. The production of hybrid ions (formed from CO and NH3 molecules) emitted from CONH3 ice has already been reported by R. Martinez et al., Int. J. Mass. Spectrom. 262 (2006) 195; here, the secondary ion emission and the modifications of the CONH3 ice structure during the temperature increase of the ice are addressed. These studies are expected to throw light on the sputtering from planetary and interstellar ices and the possible formation of new organic molecules in CONH3–H2O ice by megaelectronvolt ion bombardment. The presence of water in the CONH3 ice mixture generates molecular ion series such as (NH3)p−q(H2O)qCO+ and replaces the cluster series (NH3)nNH4+ emission by the hybrid series (NH3)I−i(H2O)i=1, 2…IH+. The distribution of NH3 and H2O molecules within the cluster groups indicates that ammonia and water mix homogenously in the icy condensate at T = 25 K. The desorption yield distribution of the cluster series (NH3)nNH4+ is described by the sum of two exponential functions: one, slow‐decreasing, attributed to the fragmentation of the solid target into clusters; and another, fast‐decreasing, due to a local sublimation followed by recombination of ammonia molecules. The analysis of the time‐temperature dependence of these two yield components gives information on the formation process of molecular ions, the transient composition of the ice target and structural changes of the ice. Data suggest that the amorphous and porous structure of the NH3 ice, formed by the condensation of the CONH3 gas at T = 25 K, survives CO sublimation until the occurrence of a phase transition around 80 K, which produces a more fragile ice structure. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of tricyclic antidepressant drugs in plasma by means of solid‐phase microextraction‐liquid chromatography‐mass spectrometry
Authors: Alves Claudete , Santos‐Neto Alvaro J. , Fernandes Christian , Rodrigues José C. , Lanças Fernando M.
Published: September 2007

Solid‐phase microextraction coupled to liquid chromatography and mass spectrometry (SPME‐LC‐MS) was used to analyze tricyclic antidepressant drugs desipramine, imipramine, nortriptyline, amitriptyline, and clomipramine (internal standard) in plasma samples. SPME was performed by direct extraction on a PDMS/DVB (60 µm) coated fiber, employing a stirring rate of 1200 rpm for 30 min, pH 11.0, and temperature of 30 °C. Drug desorption was carried out by exposing the fiber to the liquid chromatography mobile phase for 20 min, using a labmade SPME‐LC interface at 50 °C. The main variables experimentally influencing LC‐MS response were evaluated and mathematically modeled. A rational optimization with fewer experiments was achieved using a factorial design approach. The constructed empirical models were adjusted with 96–98% of explained deviation allowing an adequate data set comprehension. The chromatographic separation was realized using an RP‐18 column (150 mm × 2.1 mm, 5 µm particles) and ammonium acetate buffer (0.01 mol/l, pH 5.50) : acetonitrile (50 : 50 v/v) as mobile phase. Low detection levels were achieved with electrospray interface (0.1 ng/ml). The developed method showed specificity, linearity, precision, and limit of quantification adequate to assay tricyclic antidepressant drugs in plasma. Copyright © 2007 John Wiley & Sons, Ltd.
Characterization of a putative Xylella fastidiosa diffusible signal factor by HRGC‐EI‐MS
Authors: Colnaghi Simionato Ana Valéria , da Silva Denise Santos , Lambais Marcio Rodrigues , Carrilho Emanuel
Published: September 2007

Xylella fastidiosa (X.f.) is a plant pathogen with high levels of genomic similarity to Xanthomonas campestris pv. campestris (X.c.c.). It has been shown that X. fastidiosa synthesizes a putative diffusible signal factor (X.f.‐DSF) that activates regulation of pathogenicity factor (rpf) genes in a X.c.c. reporter system, which might be involved in the regulation of pathogenesis associated genes as in X.c.c., as well as in quorum‐sensing. The nature of the X.f.‐DSF is not known, whereas the X.c.c.‐DSF has been identified as cis‐11‐methyl‐2‐dodecenoic acid. In this work, the chemical nature of a putative X.f.‐DSF molecule, able to restore endoglucanase activity in a X.c.c. rpfF mutant, was investigated as if it was a fatty acid derivative. Bioassays with X.c.c. reporter bacterium and X.f. culture extracts, based on endoglucanase restoration activity, were also carried out in order to confirm the DSFs molecules similarities. For this reason, a gas chromatography–mass spectrometry method was developed with standard fatty acids methyl esters mixtures. The retention time, as well as the fragmentation patterns, of each standard was used to identify the DSF molecule synthesized by X.f. in the culture medium. Typical ester fragmentation patterns (the derivatized analyte) were observed, such as: McLafferty rearrangement and migration of the Hδ followed by 1,4‐hydrogen shift and cleavage of the bond CβCγ, confirming the nature of this molecule. This confirmation was corroborated by the common peaks in both spectra. Besides, the observed retention time reinforces our conclusion since it corresponds to a methyl ester with 15 carbons. Since the X.f.‐DSF molecule was tentatively identified as 12‐methyl‐tetradecanoic acid (by mass spectra library comparison), this standard compound was also analyzed, strongly suggesting that this is the identification of such a molecule. To our knowledge, this is the first time a DSF produced by X.f. has been characterized. Copyright © 2007 John Wiley & Sons, Ltd.
Statins enhance toll‐like receptor 4‐mediated cytokine gene expression in astrocytes: Implication of Rho proteins in negative feedback regulation
Authors: Konat Gregory W. , Krasowska‐Zoladek Alicja , Kraszpulski Michal
Published: September 2007

Toll‐like receptors (TLRs) are sentinels of innate immunity that recognize pathogenic molecules and trigger inflammatory response. Because inflammatory mediators are detrimental to the host, the TLR response is regulated by feedback inhibition. Statins, the inhibitors of isoprenoid biosynthesis, have been shown to be potent modulators of TLR activity, and this modulation may provide insight regarding mechanisms of the feedback inhibition. In the present study, we examined feedback mechanisms that regulate TLR4 activity in astrocytes using statins to perturb postligational signaling. Astrocytic cultures established from newborn rat brains were exposed to lipopolysaccharide (LPS), the ligand for TLR4. The up‐regulation of expression of genes encoding interleukin (IL)‐1β, IL‐6, and tumor necrosis factor‐α (TNFα) was determined by real‐time RT‐PCR. Pretreatment of the cells with either atorvastatin or simvastatin enhanced the LPS‐induced up‐regulation of cytokine gene expression. The most profound enhancement of approximately 17‐fold was observed for theIl‐6gene. The enhancements for theTnfaandIl‐1bgenes were approximately 5‐ and 3.5‐fold, respectively. Mevalonate fully reversed the effects of statins, indicating that these drugs act through the inhibition of isoprenoid synthesis. The inhibition of protein geranylgeranylation, but not protein farnesylation, mimicked the effects of statins, strongly indicating that the enhancement is mediated by the Rho proteins. In support of this notion, pretreatment of cells with toxin B, a specific inhibitor of the Rho proteins, also enhanced LPS‐triggered up‐regulation of the cytokine genes. These results indicate that the Rho proteins are involved in the activation of negative feedback inhibition of TLR4 signaling in astrocytes. © 2007 Wiley‐Liss, Inc.
Forecasting precipitation for hydroelectric power management: how to exploit GCM's seasonal ensemble forecasts
Authors: García‐Morales Marta Benito , Dubus Laurent
Published: September 2007

The EDF group is the biggest French electric power producer and distributor. Its activities are greatly related to weather and climate. In particular, optimal management of the hydroelectric power production system requires a good forecast of water resources, from several days to several months in advance. Currently, only climatology at the seasonal timescale is used for operational production management. Seasonal probabilistic forecasts would improve watershed management at some months' lead‐time if they are skilful enough. For this, two main problems have to be addressed: first, direct precipitation forecasts at this timescale have little, but positive, skill over Europe; second, the spatial scales of seasonal forecasting models are not adequate to predict local precipitation at the river basin scale. This study aims to evaluate the quality of seasonal forecasts of precipitation for 48 catchments in southern France. These are obtained by spatially downscaling global scale seasonal forecasts of geopotential height at 850 hPa. The method used is based on singular value decomposition and multiple linear regression. The statistical downscaling model is calculated from 45 years of observed local precipitation in the watersheds and geopotential fields from ERA40 re‐analysis data. The statistical model is then applied to the seasonal hindcasts from the DEMETER project. Two main results arise from this work. First, we show that it is possible to obtain useful and valuable information for EDF at the local scale from global seasonal averaged information. Second, we find that only a probabilistic multi‐model ensemble forecast approach provides useful information for EDF catchments, even with quite low skill, and that a deterministic approach, using only the ensemble mean of the forecasts, is not better than a forecast based on climatology. It has, nevertheless, to be pointed out that for operational purposes, being able to know that a forecast for a given location or date is not reliable is, in itself, valuable information. Copyright © 2007 Royal Meteorological Society
Gene expression in endoprosthesis loosening: Chitinase activity for early diagnosis?
Authors: Morawietz L. , Weimann A. , Schroeder J. H. , Kuban R. J. , Ungethuem U. , Kaps C. , Slevogt H. , Gehrke T. , Krukemeyer M. G. , Krenn V.
Published: September 2007

The aim of the study was to identify markers for the early diagnosis of endoprosthesis loosening, for the differentiation between wear particle–induced and septic loosening and to gather new insights into the pathogenesis of endoprosthesis loosening. Gene expression profiles were generated from five periprosthetic membranes of wear particle–induced and five of infectious (septic) type using Affymetrix HG U133A oligonucleotide microarrays. The results of selected differentially expressed genes were validated by RT‐PCR (n = 30). The enzyme activity and the genotype of chitinase‐1 were assessed in serum samples from 313 consecutive patients hospitalized for endoprosthesis loosening (n = 54) or for other reasons, serving as control subjects (n = 259). Eight hundred twenty‐four genes were differentially expressed with a fold change greater than 2 (data sets on http://www.ncbi.nlm.nih.gov/geo/ GSE 7103). Among these were chitinase 1, CD52, calpain 3, apolipoprotein, CD18, lysyl oxidase, cathepsin D, E‐cadherin, VE‐cadherin, nidogen, angiopoietin 1, and thrombospondin 2. Their differential expression levels were validated by RT‐PCR. The chitinase activity was significantly higher in the blood from patients with wear particle–induced prosthesis loosening (p = 0.001). However, chitinase activity as a marker for early diagnosis has a specificity of 83% and a sensitivity of 52%, due to a high variability both in the disease and in the control group. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:394–403, 2008
Ischemia/reperfusion‐induced necrosis and apoptosis in the cells isolated from rat skeletal muscle
Authors: Wang Wei Z. , Fang Xin‐Hua , Stephenson Linda L. , Khiabani Kayvan T. , Zamboni William A.
Published: September 2007

Necrosis was considered to be the solo mechanism for ischemia/reperfusion (I/R)‐induced cell death. Recent evidence from I/R models of the heart, liver, kidney, and brain indicates that apoptosis is a major contributor to I/R‐induced cell death. However, evidence of I/R‐induced apoptosis in skeletal muscle is sparse and divided. The purpose for the present study was to investigate I/R‐induced necrosis and apoptosis in the cells isolated from rat skeletal muscle. A rat gracilis muscle model was used. After surgical preparation, clamps were applied on the vascular pedicle to create 4 h of ischemia and released for 24 h of reperfusion (I/R, n = 10). Clamping was omitted in sham I/R rats (sham I/R, n = 10). The muscle samples were harvested after 24 h of reperfusion for the process of cell isolation. Cells were stained by Propidium Iodide (PI) or Annexin V‐FITC or both. Twenty thousand cells from each muscle sample were scanned and analyzed by flow cytometry. The average percentage of live cells was 45 ± 2% in the I/R group versus 65 ± 3% in the sham I/R group (p < 0.01). The average percentage of necrotic cells was 18 ± 1% in I/R versus 12 ± 1% in sham I/R (p < 0.01). The average percentage of apoptotic cells was 40 ± 3% in I/R versus 27 ± 3% in sham I/R (p < 0.01). Our results clearly demonstrated that I/R not only causes necrosis, but also accelerates apoptosis in the cells isolated from rat skeletal muscle. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:351–356, 2008
Matrix‐induced autologous chondrocyte implantation in sheep: objective assessments including confocal arthroscopy
Authors: Jones C. W. , Willers C. , Keogh A. , Smolinski D. , Fick D. , Yates P. J. , Kirk T. B. , Zheng M. H.
Published: September 2007

The assessment of cartilage repair has largely been limited to macroscopic observation, magnetic resonance imaging (MRI), or destructive biopsy. The aims of this study were to establish an ovine model of articular cartilage injury repair and to examine the efficacy of nondestructive techniques for assessing cartilage regeneration by matrix‐induced autologous chondrocyte implantation (MACI). The development of nondestructive assessment techniques facilitates the monitoring of repair treatments in both experimental animal models and human clinical subjects. Defects (Ø 6 mm) were created on the trochlea and medial femoral condyle of 21 sheep randomized into untreated controls or one of two treatment arms: MACI or collagen‐only membrane. Each group was divided into 8‐, 10‐, and 12‐week time points. Repair outcomes were examined using laser scanning confocal arthroscopy (LSCA), MRI, histology, macroscopic ICRS grading, and biomechanical compression analysis. Interobserver analysis of the randomized blinded scoring of LSCA images validated our scoring protocol. Pearson correlation analysis demonstrated the correlation between LSCA, MRI, and ICRS grading. Testing of overall treatment effect independent of time point revealed significant differences between MACI and control groups for all sites and assessment modalities (Asym Sig < 0.05), except condyle histology. Biomechanical analysis suggests that while MACI tissue may resemble native tissue histologically in the early stages of remodeling, the biomechanical properties remain inferior at least in the short term. This study demonstrates the potential of a multisite sheep model of articular cartilage defect repair and its assessment via nondestructive methods. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:292–303, 2008
Liver Transplantation in Patients Over 60 and 65 Years
Authors: Cross Timothy J.S. , Antoniades Charalambos G. , Muiesan Paolo , Al-Chalabi Thawab , Aluvihare Varuna , Agarwal Kosh , Portmann Bernard C. , Rela Mohammed , Heaton Nigel D. , O'Grady John G. , Heneghan Michael A.
Published: September 2007

With increased demand for liver transplantation (LT), outcomes of older recipients have been subjected to greater scrutiny, as previous studies have demonstrated poorer survival outcomes. Outcomes of 77 patients aged > 65 yr (group 1) who underwent transplantation between 1988 and 2003 at King's College Hospital, London, were compared with all recipients aged between 60 and 64 yr (group 2, n = 137) and 202 time-matched control patients with chronic liver disease aged between 18-59 yr (group 3). Patient survival at 30-days for groups 1, 2, and 3 were 99%, 94%, and 94%, respectively (P = not significant [NS]). At 1-yr, survival in the 3 groups was 82%, 86%, and 83%, respectively (P = NS), and at 5-yr patient survival was comparable (73%, 80%, and 78%, respectively) (P = NS). Episodes of acute cellular rejection (ACR) were fewer in the older cohorts (43% vs. 45% vs. 61%, P = 0.0016), although there was no significant difference identified in the numbers of patients in each group who experienced ACR (P = 0.16). A similar but nonsignificant trend was identified for rates of chronic rejection among the groups. In conclusion, these data suggest that survival of patients over 60 and 65 yr undergoing LT is satisfactory, at least in the first 5-yr posttransplantation. In addition, patients over 65 yr experience less rejection, with good graft survival. Thus, LT should not be denied to patients >65 yr on the basis of age alone, once a comprehensive screen for comorbidity has been undertaken. Liver Transpl 13:1382–1388. 2007. © 2007 AASLD.
Resistance to Combined Ganciclovir and Foscarnet Therapy in a Liver Transplant Recipient with Possible Dual-Strain Cytomegalovirus Coinfection
Authors: Rodriguez John , Casper Katherine , Smallwood Gregory , Stieber Andrei , Fasola Carlos , Lehneman Jennifer , Heffron Thomas
Published: September 2007

We present a case report of a cytomegalovirus (CMV)-seronegative, 58-year-old male who received a CMV-seropositive donor liver transplant without CMV prophylaxis. On postoperative day 30, the patient developed primary CMV disease that responded to ganciclovir. On postoperative day 114, however, he was diagnosed with recurrent CMV infection. Despite aggressive, combined antiviral treatment with ganciclovir and foscarnet and reduction of immunosuppression, viral clearance was never achieved. Serum samples were collected throughout the infectious process for viral DNA analysis. Portions of the UL97 and UL54 genes were amplified and compared to the AD169 wild-type strain. Sequencing studies revealed the presence of mutations in viral isolates obtained after clinical resistance was observed. These mutations were not present in samples obtained during the primary CMV infection. Our findings suggest the presence of coinfection with at least 2 different strains of CMV rather than induction of mutations after ganciclovir therapy. Liver Transpl 13:1396–1400. 2007. © 2007 AASLD.
Lessons Learned From Anatomic Variants of the Hepatic Artery in 1,081 Transplanted Livers
Authors: López-Andújar Rafael , Moya Angel , Montalvá Eva , Berenguer Marina , De Juan Manuel , San Juan Fernando , Pareja Eugenia , Vila Juan José , Orbis Francisco , Prieto Martín , Mir José
Published: September 2007

The aim of this study is to contribute our experience to the knowledge of the anatomic variations of the hepatic arterial supply. The surgical anatomy of the extrahepatic arterial vascularization was investigated prospectively in 1,081 donor cadaveric livers, transplanted at La Fe University Hospital from January 1991 to August 2004. The vascular anatomy of the hepatic grafts was classified according to Michels description (Am J Surg 1966;112:337-347) plus 2 variations. Anatomical variants of the classical pattern were detected in 30% of the livers (n = 320). The most common variant was a replaced left artery arising from the left gastric artery (9.7%) followed by a replaced right hepatic artery arising from the superior mesenteric artery (7.8%). In conclusion, the information about the different hepatic arterial patterns can help in reducing the risks of iatrogenic complications, which in turn may result in better outcomes not only following surgical interventions but also in the context of radiological treatments. Liver Transpl 13:1401–1404, 2007. © 2007 AASLD
Can Peripheral Venous Pressure Be An Alternative to Central Venous Pressure During Right Hepatectomy in Living Donors?
Authors: Choi Soo Joo , Gwak Mi Sook , Ko Justin Sang , Kim Gaab Soo , Kim Tae Hyeong , Ahn Hyun , Kim Jie Ae , Yang Mikyung , Lee Sang , Kim Myung
Published: September 2007

The safety of living donors is a matter of cardinal importance in addition to obtaining optimal liver grafts to be transplanted. Central venous pressure (CVP) is known to have significant correlation with the amount of bleeding during parenchymal transection and many centers have adopted CVP monitoring for right hepatectomy. However, central line cannulation can induce some serious complications. Peripheral venous pressure (PVP) has been suggested as a comparable alternative to CVP. The aim of this study was to determine whether a clinically acceptable agreement or a reliable correlation between CVP and PVP exist and if CVP can be replaced by PVP in living liver donors. A central venous catheter was placed through the right internal jugular vein and a peripheral venous catheter was inserted at antecubital fossa in the right arm. CVP and PVP were recorded in 15-minunte intervals in 50 adult living donors. The paired data were divided into 3 stages: preparenchymal transection, parenchymal transection, and postparenchymal transection. A total of 1,430 simultaneous measurements of CVP and PVP were recorded. Overall, the PVP, CVP, and bias were 7.0 ± 2.46, 5.9 ± 2.32, and 1.16 ± 1.12 mmHg, respectively. A total of 88.9% of all measurements were clinically within acceptable limits of bias (±2 mmHg). Regression analysis showed a high correlation coefficient between PVP and CVP (r = 0.893; P < 0.001) and the limits of agreement were −1.03 to 3.34 overall. In conclusion, frequencies of differences, bias, correlation coefficient, and limits of agreement between PVP and CVP remained relatively constant throughout the operation. Therefore, PVP measurement in the arm can be an alternative to predict CVP and further, obviate central venous catheter-related complications in living liver donors. Liver Transpl 13:1414–1421, 2007. © 2007 AASLD.
Human Leukocyte Antigen and Adult Living-Donor Liver Transplantation Outcomes
Authors: Jakab Simona S. , Navarro Victor J. , Colombe Beth W. , Daskalakis Constantine , Herrine Steven K. , Rossi Simona
Published: September 2007

Human leukocyte antigen (HLA) compatibility has no clinically significant impact in cadaveric liver transplantation. Less is known regarding living-donor liver transplantation (LDLT). Our prior analysis of the Organ Procurement and Transplantation Network (OPTN) database suggested a higher graft failure rate in patients who underwent LDLT from donors with close HLA match. We further investigated the effect of HLA-A, -B, and -DR matching on 5-yr graft survival in adult LDLT by analyzing OPTN data regarding adult LDLT performed between 1998 and 2005. We evaluated associations between 5-yr graft survival and total, locus-specific, and haplotype match levels. Separate analyses were conducted for recipients with autoimmune (fulminant autoimmune hepatitis, cirrhosis secondary to autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis) or nonautoimmune liver disease. Multivariable Cox proportional hazard models were used to evaluate interactions and adjust for potential confounders. Among 631 patients with available donor/recipient HLA data, the degree of HLA match had no significant effect on 5-yr graft survival, even when analyzed separately in recipients with autoimmune vs. nonautoimmune liver disease. To be able to include all 1,838 adult LDLTs, we considered a first-degree related donor as substitute for a close HLA match. We found no difference in graft survival in related vs. unrelated pairs. In conclusion, our results show no detrimental impact of close HLA matching on graft survival in adult LDLT, including in recipients with underlying autoimmune liver disease. Liver Transpl 13:1405–1413, 2007. © 2007 AASLD.
Liver Transplantation Using Suboptimal Grafts
Authors: D'Amico Francesco , Vitale Alessandro , Gringeri Enrico , Valmasoni Michele , Carraro Amedeo , Brolese Alberto , Zanus Giacomo , Boccagni Patrizia , D'Amico Davide Francesco , Cillo Umberto
Published: September 2007

In recent years, an increasing number of suboptimal grafts has been used to reduce the gap between the supply and demand of organs for liver transplantation (LT). In this randomized prospective study, we tested the impact of donor harvesting technique on the posttransplantation outcome of suboptimal donor livers. A modified double perfusion (MDP) technique (aortic and portal cooling with tourniquet clamping of splenomesenteric vein inflow) was compared with the single aortic perfusion (SAP) technique. Between February and November 2005, 35 suboptimal grafts were randomly assigned to either technique (18 MDP livers and 17 SAP livers). Donor and recipient variables were comparable in the 2 study groups. The SAP group had significantly higher blood transaminases and bilirubin levels after LT. The prevalence of graft primary dysfunction (PDF) was also significantly higher (P = 0.01) in the SAP group (35%) than in the MDP group (5%). In 5 cases, all in the SAP group (P = 0.02), early re-LT (<30 days) was needed. The 6-month patient and graft survival rates were significantly higher in the MDP (100% in both cases) than in the SAP group (68% and 58%, respectively). The study was stopped in November 2005, when the interim analysis revealed such markedly significant differences between the two groups. In conclusion, the present study showed a very low prevalence of PDF, death, and re-LT after transplantation with suboptimal liver when a MDP technique was used to harvest the donor graft. Liver Transpl 13:1444–1450, 2007. © 2007 AASLD.