bluuebunny/crossref_metadata_2025 huggingface dataset:
VEGF stimulates PKD‐mediated CREB‐dependent orphan nuclear receptor Nurr1 expression: Role in VEGF‐induced angiogenesis
Authors: Zhao Dezheng , Desai Sachin , Zeng Huiyan
Published: August 2010

New vessel formation is critical for solid tumor growth and it is primarily stimulated by the most potent angiogenic factor vascular endothelial growth factor (VEGF or VEGF‐A165). VEGF promotes endothelial cell proliferation by initiating signaling cascades to increase gene transcription. Recent works showed that VEGF potently and rapidly induces expression of orphan nuclear receptor Nurr1 in endothelial cells. However, the signaling pathway for VEGF‐induced Nurr1 expression and its role in VEGF‐induced endothelial cell proliferation and angiogenic response have not been examined. In our study, we first show that VEGF significantly induces expression of Nurr1 mRNA, protein and its promoter activity in cultured endothelial cells. Furthermore, the promoter analysis shows that deletion of the putative cAMP‐responsive element binding protein (CREB) site in the proximal region of the promoter markedly reduces VEGF‐induced promoter activity whereas deletion of the upstream NF‐κB site has moderate effect. Transfection of a dominant negative CREB mutant (K‐CREB) or mutation of this putative CREB site in the Nurr1 promoter attenuates VEGF‐induced Nurr1 expression. VEGF also stimulates the binding of nuclear CREB protein to its site in the Nurr1 promoter in vitro and in vivo. Moreover, using pharmacological inhibitors and molecular approaches, we show that VEGF‐induced CREB activation is largely mediated by protein kinase C‐dependent protein kinase D activation. Finally, our data indicate that knockdown of endogenous Nurr1 expression attenuates VEGF‐induced endothelial cell proliferation, migration and in vivo matrigel angiogenesis, suggesting its potential importance in mediating VEGF‐induced tumor angiogenesis.
Ethanol‐mediated carcinogenesis in the human esophagus implicates CYP2E1 induction and the generation of carcinogenic DNA‐lesions
Authors: Millonig Gunda , Wang Ying , Homann Nils , Bernhardt Friederike , Qin Hua , Mueller Sebastian , Bartsch Helmut , Seitz Helmut K.
Published: August 2010

Chronic alcohol consumption is a major risk factor for esophageal cancer. Various mechanisms may mediate carcinogenesis including the genotoxic effect of acetaldehyde and oxidative stress. Ethanol exerts its carcinogenic effect in the liver among othersviathe induction of cytochrome P450 2E1 (CYP2E1) and the generation of carcinogenic etheno‐DNA adducts. Here we investigated if such effects can also be observed in the human esophagus. We studied nontumorous esophageal biopsies of 37 patients with upper aerodigestive tract cancer and alcohol consumption of 102.3 ± 131.4 g/day (range: 15–600 g) as well as 16 controls without tumors (12 teetotalers and 4 subjects with a maximum of 25 g ethanol/day). CYP2E1, etheno‐DNA adducts and Ki67 as a marker for cell proliferation were determined immunohistologically. Chronic alcohol ingestion resulted in a significant induction of CYP2E1 (p= 0.015) which correlated with the amount of alcohol consumed (r= 0.6,p< 0.001). Furthermore, a significant correlation between CYP2E1 and the generation of the carcinogenic exocyclic etheno‐DNA adducts 1,N6‐ethenodeoxyadenosine (r= 0.93,p< 0.001) and 3,N4‐ethenodeoxycytidine (r= 0.92,p< 0.001) was observed. Etheno‐DNA adducts also correlated significantly with cell proliferation (p< 0.01), which was especially enhanced in patients who both drank and smoked (p< 0.001). Nonsmokers and nondrinkers had the lowest rate of cell proliferation, CYP2E1 expression and DNA lesions. Our data demonstrate for the first time an induction of CYP2E1 in the esophageal mucosa by ethanol in a dose dependent manner in man and may explain, at least in part, the generation of carcinogenic DNA lesions in this target organ.
The selective VEGFR1‐3 inhibitor axitinib (AG‐013736) shows antitumor activity in human neuroblastoma xenografts
Authors: Rössler Jochen , Monnet Yann , Farace Francoise , Opolon Paule , Daudigeos‐Dubus Estelle , Bourredjem Abderrahmane , Vassal Gilles , Geoerger Birgit
Published: August 2010

Tumor angiogenesis in childhood neuroblastoma is an important prognostic factor suggesting a potential role for antiangiogenic agents in the treatment of high‐risk disease. Within the KidsCancerKinome project, we evaluated the new oral selective pan‐VEGFR tyrosine kinase inhibitor axitinib (AG‐013736) against neuroblastoma cell lines and the subcutaneous and orthotopic xenograft model IGR‐N91 derived from a primary bone marrow metastasis. Axitinib reduced cell proliferation in a dose‐dependent manner with IC50 doses between 274 and >10,000 nmol/l. Oral treatment with 30 mg/kg BID for 2 weeks in advanced tumors yielded significant tumor growth delay, with a median time to reach five times initial tumor volume of 11.4 days compared to controls (p = 0.0006) and resulted in significant reduction in bioluminescence. Simultaneous inhibition of VEGFR downstream effector mTOR using rapamycin 20 mg/kg q2d×5 did not statistically enhance tumor growth delay compared to single agent activities. Axitinib downregulated VEGFR‐2 phosphorylation resulting in significantly decreased microvessel density (MVD) and overall surface fraction of tumor vessels (OSFV) in all xenografts as measured by CD34 immunohistochemical staining (mean MVD ± SD and OSFV at 14 days 21.27 ± 10.03 in treated tumors vs. 48.79 ± 17.27 in controls and 0.56% vs. 1.29%; p = 0.0006, respectively). We further explored the effects of axitinib on circulating mature endothelial cells (CECs) and endothelial progenitor cells (CEPs) measured by flow cytometry. While only transient modification was observed for CECs, CEP counts were significantly reduced during and up to 14 days after end of treatment. Axitinib has potent antiangiogenic properties that may warrant further evaluation in neuroblastoma.
Fiber‐optic probes forin vivodepth‐resolved neuron‐activity mapping
Authors: Doronina‐Amitonova Lyubov V. , Fedotov Il'ya V. , Ivashkina Olga I. , Zots Marina A. , Fedotov Andrei B. , Anokhin Konstantin V. , Zheltikov Aleksei M.
Published: August 2010

Specialty fiber probes are used forin vivodepth‐resolved mapping of neuron activity through the optical detection of fluorescent‐protein reporters expressed inside the living brain of anesthetized transgenic mice. Supercontinuum radiation produced by highly nonlinear photonic‐crystal fibers is employed to demonstrate a simultaneous multicolor interrogation of several biomarkers in a model aqueous solution system, thus suggesting the way toward a multiplex mapping of various types of neuron dynamics inside the living brain. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Retrieving skin properties fromin vivospectral reflectance measurements
Authors: Yudovsky Dmitry , Pilon Laurent
Published: August 2010

A previously developed inverse method was applied toin vivonormal‐hemispherical spectral reflectance measurements taken on the inner and outer forearm as well as the forehead of healthy white Caucasian and black African subjects. The inverse method was used to determine the thickness and melanin concentration in the epidermis, dermal blood volume fraction and oxygen saturation, and skin's spectral scattering coefficient. It was established that changes in melanin concentration due to racial difference and tanning, and differences in epidermal thickness and blood volume with anatomical location were detectable. The retrieved values were also consistent with independent measurements reported in the literature. The same method could be used for optical diagnosis of pathologies affecting the structure and pigmentation of human skin. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High‐ and low‐frequency mechanical properties of living starfish oocytes
Authors: Pesce Giuseppe , Selvaggi Lara , Rusciano Giulia , Sasso Antonio
Published: August 2010

We studied the mechanical properties of living starfish oocytes belonging to two species, Astropecten Auranciacus and Asterina pectinifera, over a wide range of timescales. We monitored the Brownian motion of microspheres injected in the cytoplasm using laser particle‐tracking (LPT) and video multiple‐particle‐tracking (MPT) techniques, to explore high‐ and low‐frequency response ranges, respectively. The analysis of the mean‐square‐displacements (MSD) allowed us to characterize the samples on different timescales. The MSD behavior is explained by three power‐law exponents: for short times (τ < 1 ms) it reflects the semiflexible behavior of the actin network; for intermediate timescales (1 ms < τ < 1 s) it is similar to that of a soft‐glass material; finally for long times (τ > 1 s) it behaves mainly like a viscous medium. We computed and compared the viscoelastic moduli using a recently proposed model describing the frequency response of the cell material. The large fluctuations found in the MSD over hundreds of trajectories indicate and confirm the significant cytoplasm heterogeneity. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gene expression, glycocalyx assay, and surface properties of human endothelial cells cultured on hydrogel matrix with sulfonic moiety: Effect of elasticity of hydrogel
Authors: Yang Jing Jing , Chen Yong Mei , Kurokawa Takayuki , Gong Jian Ping , Onodera Shin , Yasuda Kazunori
Published: August 2010

We measured the gene expression, glycocalyx content, and surface properties of human coronary artery endothelial cells (HCAECs) cultured on poly(sodium p‐styrene sulfonate) (PNaSS) hydrogels with various levels of elasticity ranged in 3–300 kPa. We found that all HCAECs reached confluence on these hydrogels while retaining the similar expression of EC‐specific markers to that on polystyrene (PS), a widely used scaffold in cell culture in vitro. Real‐time polymerase chain reaction (PCR) and glycosaminoglycan (GAG) assay showed that the amount of EC‐specific glycocalyx secreted by HCAECs cultured on PNaSS gels was higher than that cultured on PS, and it increased with an increase of gel elasticity. Furthermore, the HCAECs cultured on PNaSS gels showed excellent property against platelet adhesion and lower surface friction than that on PS. The platelet adhesion and surface friction of HCAECs cultured on PNaSS gels also depend on the elasticity of gels. The largest amount of EC‐specific glycocalyx, excellent blood compatibility, and the lowest friction were observed when the elastic modulus of the gel was larger than 60 kPa. Overall, HCAECs cultured on these hydrogels have better properties than those cultured on PS scaffold, demonstrating the PNaSS gels can be used as potential tissue engineering material for blood vessels. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Oncostatin M synergistically induces CXCL10 and ICAM‐1 expression in IL‐1β‐stimulated‐human gingival fibroblasts
Authors: Hosokawa Yoshitaka , Hosokawa Ikuko , Ozaki Kazumi , Nakae Hideaki , Matsuo Takashi
Published: August 2010

Periodontitis is a chronic bacterial infection of tooth‐supporting structures. T‐helper type 1 (Th1) cells are related to the exacerbation of periodontal disease. Human gingival fibroblasts (HGFs), the major cell type in periodontal connective tissues, are involved in immunological response in periodontal tissues. However, it is uncertain whether HGFs are related to Th1 response. Chemokine (C‐X‐C motif) ligand 10 (CXCL10) is a cytokine, that is related to Th1 cells migration. Intercellular adhesion molecule (ICAM)‐1 is involved in Th1 cells retention and activation in inflamed tissue. The aim of this study is to examine the effect of oncostatin M (OSM) on CXCL10 and ICAM‐1 expression in HGFs. OSM stimulation induced CXCL10 and ICAM‐1 expression in HGFs. Moreover, the synergistic effects of CXCL10 release and ICAM‐1 expression in HGFs were observed with combined stimulation of interleukin (IL)‐1β and OSM. OSM increased type 1 IL‐1 receptor (IL‐1R1) expression, and IL‐1β enhanced OSMRβ expression on HGFs. IL‐1β + OSM stimulation enhanced the phosphorylation of inhibitor of nuclear factor κB (IκB)‐α, signal transducer and activator of transcription (STAT)3, c‐Jun N terminal kinase (JNK), and protein kinase B (Akt) compared to OSM or IL‐1β stimulation. CXCL10 production from OSM + IL‐1β stimulated HGFs was suppressed by nuclear factor (NF)‐κB, STAT3, JNK, and phosphoinositide‐3‐kinase (PI3K) inhibitors. On the other hand, only NF‐κB and STAT3 inhibitors suppressed ICAM‐1 expression enhanced by OSM + IL‐1β treatment. These effects of OSM and IL‐1β may promote Th1 cells infiltration and retention in periodontally diseased tissues and be related to exacerbation of periodontal disease. J. Cell. Biochem. 111: 40–48, 2010. © 2010 Wiley‐Liss, Inc.
Prospective evaluation of a cognitive vulnerability‐stress model for depression: the interaction of schema self‐structures and negative life events
Authors: Seeds Pamela M. , Dozois David J.A.
Published: August 2010

This study tested the diathesis‐stress component of Beck's (1967) cognitive theory of depression. Initially, participants completed measures assessing cognitive organization of the self‐schema and depressive symptoms. One year later, participants completed measures assessing cognitive organization of the self‐schema, depressive symptoms, and negative life events. Hierarchical multiple regression analyses, controlling for initial depression, indicated that more tightly interconnected negative content was associated with greater elevations in depressive symptoms following the occurrence of life events. More diffusely interconnected positive content for interpersonal self‐referent information also interacted with life events to predict depressive symptoms. Cognitive organization dimensions showed moderate to high stability across the follow‐up, suggesting that they may be trait‐like vulnerability factors. Implications for the cognitive vulnerability‐stress model of depression are discussed. © 2010 Wiley Periodicals, Inc. J Clin Psychol 66:1–17, 2010.
Ultrastructure of spermiogenesis in the American alligator,Alligator mississippiensis(Reptilia, Crocodylia, Alligatoridae)
Authors: Gribbins Kevin M. , Siegel Dustin S. , Anzalone Marla L. , Jackson Daniel P. , Venable Katherine J. , Rheubert Justin L. , Elsey Ruth M.
Published: August 2010

Testicular samples were collected to describe the ultrastructure of spermiogenisis inAlligator mississipiensis(American Alligator). Spermiogenesis commences with an acrosome vesicle forming from Golgi transport vesicles. An acrosome granule forms during vesicle contact with the nucleus, and remains posterior until mid to late elongation when it diffuses uniformly throughout the acrosomal lumen. The nucleus has uniform diffuse chromatin with small indices of heterochromatin, and the condensation of DNA is granular. The subacrosome space develops early, enlarges during elongation, and accumulates a thick layer of dark staining granules. Once the acrosome has completed its development, the nucleus of the early elongating spermatid becomes associated with the cell membrane flattening the acrosome vesicle on the apical surface of the nucleus, which aids in the migration of the acrosomal shoulders laterally. One endonuclear canal is present where the perforatorium resides. A prominent longitudinal manchette is associated with the nuclei of late elongating spermatids, and less numerous circular microtubules are observed close to the acrosome complex. The microtubule doublets of the midpiece axoneme are surrounded by a layer of dense staining granular material. The mitochondria of the midpiece abut the proximal centriole resulting in a very short neck region, and possess tubular cristae internally and concentric layers of cristae superficially. A fibrous sheath surrounds only the axoneme of the principal piece. Characters not previously described during spermiogenesis in any other amniote are observed and include (1) an endoplasmic reticulum cap during early acrosome development, (2) a concentric ring of endoplasmic reticulum around the nucleus of early to middle elongating spermatids, (3) a band of endoplasmic reticulum around the acrosome complex of late developing elongate spermatids, and (4) midpiece mitochondria that have both tubular and concentric layers of cristae. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc.
Mineral dust around the Sahara—from source to sink. A review with emphasis on contributions of the German soil science community in the last twenty years
Authors: Herrmann Ludger , Jahn Reinhold , Maurer Thomas
Published: August 2010

Natural mineral dust has manifold environmental effects reaching from fertilizing aquatic and terrestrial ecosystems to affecting the earth's radiation balance and thus impacting on climate. The Sahara is considered the largest source of natural mineral dust on the globe, so much research attention has been paid to source identification, dust mobilization, transport, and effects in the sink areas. This paper gives a review of the research results concerning these topics emphasizing soil‐science‐related aspects of the last 20 y and the identification of knowledge gaps.
Hydrogen bonding in different pyrimidine–methanol clusters probed by polarized Raman spectroscopy and DFT calculations
Authors: Singh Dheeraj K. , Mishra Shivangi , Ojha Animesh K. , Srivastava Sunil K. , Schlücker S. , Asthana B. P. , Popp J. , Singh Ranjan K.
Published: August 2010

We report on the hydrogen bonding between pyrimidine (Pd) and methanol (M) as H‐donor in this study. Hydrogen bonds between pyrimidine and methanol molecules as well as those between different methanol molecules significantly influence the spectral features at high dilution. The ring‐breathing mode ν1 of the reference system Pd was chosen as a marker band to probe the degree of hydrogen bonding. Polarized Raman spectra in the region 970–1020 cm−1 for binary mixtures of (pyrimidine + methanol) at 28 different mole fractions were recorded. A Raman line shape analysis of the isotropic Raman line profiles at all concentrations revealed three distinct spectral components at mole fractions of Pd below 0.75. The three components are attributed to three distinct groups of species: ‘free Pd’ (pd), ‘Pd with low methanol content’ (pd1) and ‘Pd with high‐methanol content’ (pd2). The two latter species differ considerably in the pattern and the strengths of the hydrogen bonds. The results of density functional theory calculations on structures and vibrational spectra of neat Pd and eight Pd/M complexes with varying methanol content support our interpretations of the experimental results. A nice spectra–structure correlation for the different cluster subgroups was obtained, similar to earlier results obtained for Pd and water. Apart from N···H and O···H hydrogen bonds between pyrimidine and methanol, O···H hydrogen bonds formed among the methanol molecules in the cluster at high methanol content also play a crucial role in the interpretation of the experimental results. Copyright © 2010 John Wiley & Sons, Ltd.
A method of extracting ginsenosides from Panax ginseng by pulsed electric field
Authors: Hou Jingang , He Shaoyu , Ling Mingsong , Li Wei , Dong Rui , Pan Yongqi , Zheng Yinan
Published: August 2010

The objective of this study was to develop and optimize a pulsed electric field (PEF) extraction method. Various experimental conditions, including electric field intensity and frequency, were evaluated against extraction methods. The content of six major ginsenosides (Rg1, Re, Rb1, Rc, Rb2, and Rd) were quantified by HPLC. The results indicated that the highest yield of the ginsenoside is 12.69 mg/g by PEF using the conditions of 20 kV/cm electric field intensity, 6000 Hz frequency, 70% ethanol–water solution, and 150 L/h velocity. The yield of the ginsenoside of PEF extraction method is higher than the other five methods, such as microwave‐assisted extraction, heat reflux extraction, ultrasonic‐assisted extraction, accelerated solvent extraction, and ultrahigh pressure extraction, The whole extraction process of PEF takes less than 1 s, which is much less than the heat reflux extraction method for 6 h and even newly used technique ultrahigh pressure extraction method of 2 min. The high efficiency, shorter extraction times, and lower energy cost of PEF extraction method can be applied in the industrial production of saponins from Panax ginseng. The PEF extraction method is a promising and constructive method to extract ginsenosides.
Characterization of phenolic and other polar compounds in a lemon verbena extract by capillary electrophoresis‐electrospray ionization‐mass spectrometry
Authors: Quirantes‐Piné Rosa , Arráez‐Román David , Segura‐Carretero Antonio , Fernández‐Gutiérrez Alberto
Published: August 2010

In this study, a CE‐MS method has been developed to carry out the qualitative characterization of a lemon verbena (Lippia citriodora) extract for the first time. The CE and ESI‐MS parameters were optimized with respect to resolution, analysis time and peak shape in order to maximize the number of compounds detected and the sensitivity of their determination. The use of two different MS analyzers, TOF‐MS and IT‐MS, enabled the tentative identification of the major components of this extract. Thus, using this method, 16 compounds were determined. Some of them have been previously identified by HPLC methods, although four compounds were also found for the first time in lemon verbena such as asperuloside, tuberonic acid glucoside or 5′‐hydroxyjasmonic acid 5′‐O‐glucoside, shanzhiside and ixoside. These results demonstrate that CE‐MS generates data complementary to those obtainable by HPLC‐MS and it is particularly suited to the analysis of plant metabolites.
Macroporous molecularly imprinted monolithic polymer columns for protein recognition by liquid chromatography
Authors: Liu Jinxiang , Deng Qiliang , Yang Kaiguang , Zhang Lihua , Liang Zhen , Zhang Yukui
Published: August 2010

Macroporous cytochrome c (cyc)‐imprinted monolithic polyarylamide columns were prepared, and applied for the template protein recognition by HPLC. With cyc (18.8 mg) as template, the imprinted monolithic materials were in situ polymerized in an HPLC column tube, with methacrylamide (450 mg), methacrylic acid (15.8 mg), piperazine diacrylamide (720 mg) and ammonium sulfate (390 mg) dissolved in 5 mL of phosphate buffer (pH 7.4), initiated by ammonium persulfate and TEMED. After the reaction, cyc was removed with acetic acid (10%, v/v) containing 10% w/v SDS. The non‐imprinted monolithic column was prepared under the same procedure except without cyc. Retention of cyc and its competitive protein, lysozyme (lys), on molecular‐imprinting polymer (MIP) and non‐imprinted polymer columns was studied. When the pH value of mobile phase was 4.0, on MIP column, the retention factors of cyc and lys were 2.0 and 1.3, respectively. However, those on non‐imprinted polymer column were very similar, both as 1.1. Even in competitive environment, a mixture of cyc and lys could be separated on MIP column under gradient elution, with resolution as 1.2. These results indicate that protein‐imprinted monolithic polymer columns could offer obvious affinity and specific recognition to the template protein.
Corrosion performance of epoxy coatings modified by nanoparticulate SiO2
Authors: Li W. , Tian H. , Hou B.
Published: August 2010

Electrochemical impedance spectroscopy (EIS) was employed to investigate the corrosion performance of nanoparticulate SiO2 modified epoxy coatings on carbon steel in 3.5 wt% NaCl solution, coupled with salt spray test. Capacitance‐gravimetric methods and delamination tests were performed to analyze the water uptake behavior and interface stability against delamination of modified coatings, respectively. Four systems were studied, including a clear coating and three pigmented coatings (with 1, 2, and 3 wt% nanoparticulate SiO2). The experimental results showed that nanoparticulate SiO2 particles can improve the anti‐corrosion performance of the coatings and the optimal addition content is 2 wt%. The results obtained with capacitance‐gravimetric measurements showed that the diffusion process of water through epoxy coatings with different pigment volume concentration (PVC) obeyed the second Fick's diffusion law in the initial period. Adding nanoparticulate SiO2 into epoxy coatings can act effectively. The positive influence is attributed to the reaction between nanoparticles and epoxy resin which is confirmed by FTIR, improving the barrier and dispersion effectiveness of coatings. The negative one is increasing the number of pores in the coatings when the adding amount is beyond the critical PVC.
Modular StarPEG‐Heparin Gels with Bifunctional Peptide Linkers
Authors: Tsurkan Mikhail V. , Chwalek Karolina , Levental Kandice R. , Freudenberg Uwe , Werner Carsten
Published: August 2010

Cell responsive materials are instrumental to regenerative therapies. Here, we report about a novel biohybrid hydrogel that consists of heparin and peptide‐conjugated star‐shaped poly(ethylene glycol), crosslinked by peptide units that combine matrix metalloproteinase (MMP) sensitivity and cell adhesive modules. Taking advantage of the high affinity of vascular endothelial growth factor to heparin, we illustrate the applicability of our hydrogels as a novel system that is supportive of cellular remodeling and three‐dimensional migration of human endothelial cells.

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Resveratrol (3,5,4′‐trihydroxystilbene) protects pregnant mother and fetus from the immunotoxic effects of 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin
Authors: Singh Narendra P. , Singh Ugra S. , Nagarkatti Mitzi , Nagarkatti Prakash S.
Published: August 2010

Scope: The “fetal basis of adult disease” hypothesis proposes that prenatal exposure to environmental stress can lead to increased susceptibility to clinical disorders later in life.In uteroexposure of fetus to 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) leads to alterations in T‐cell differentiation in the thymus and increased susceptibility to autoimmune disease later in life. TCDD triggers toxicity through activation of aryl hydrocarbon receptor and severely affects maternal and fetal immune system during pregnancy.

Methods and results: In this study, using a mouse model, we investigated if administration of resveratrol (RES; 3,5,4′‐trihydroxystilbene) would inhibit immunotoxicity induced by TCDD during pregnancy in the mother and fetus. We observed that RES protected not only normal nonpregnant mice but also pregnant mothers and their fetuses from TCDD‐induced thymic atrophy, apoptosis, and alterations in the expression of T‐cell receptor and costimulatory molecules as well as T‐cell differentiation. In addition, there was significantly reduced expression of CYP1A1 in thymi of both the mother and the fetus when RES was usedin vivopost‐TCDD exposure.

Conclusion: In conclusion, these studies demonstrate that consumption of RES, a natural plant product, during pregnancy, may afford protection to the mother and the fetus from the toxicity induced by environmental pollutants that mediate their effects through activation of aryl hydrocarbon receptor.
Titelbild
Authors: Erdöl‐Raffinerie Mitteldeutsche
Published: August 2010

Halbzeit auf Europas größter Industriebaustelle, der neuen Erdölraffinerie Leuna 2000, die im Herbst 1997 angefahren wird [zu Seite 896].
Olympiade der Tenside
Authors: Hauthal Hermann G.
Published: August 2010

Neben der Diskussion wirtschaftlicher Aspekte und von Rohstofffragen zog der 4. Welt‐Tensid‐Kongreß eine positive Bilanz hinsichtlich der umfangreichen Aktivitäten der Branche zum Nachweis der ökologischen Unbedenklichkeit der kommerziell eingesetzten Tenside. Neue Synthesen und Technologies Fortschritte in der Analytik, Charakterisierung und Anwendung von Tensiden waren weitere Schwerpunkte des Programms.
Deutsch‐japanisches Metallorganiker‐Treffen
Authors: Gansüuer Andreas
Published: August 2010

Über Metall‐katalysierte und Metall‐induzierte Transformationen für effiziente organische Synthesen trugen 15 japanische und 15 deutsche Chemiker auf dem “Japanese German Joint Symposium” im Juni vor. Im Vordergrund standen neue katalytische Methoden und Anwendungen für die Naturstoffsynthese.
GDNF: Signalweg entschlüsselt
Authors: Maelicke Alfred
Published: August 2010

Natürliche Signalmoleküle, die das Überleben von Neuronen fördern, bieten Therapieansätze für die soziomedizinisch wohl bedrückendste Gruppe von Erkrankungen, die neurodegenerativen Alterserkrankungen, wie Morbus Parkinson, amyotrophe Lateralsklerose und Alzheimersche Demenz. In diesem Zusammenhang ist der glial‐cell‐line‐derived neurotrophic factor (GDNF) von besonderem Interesse. Durch molekulargenetische Methoden konnten nun der Signalweg wie auch eine wesentlich breitere Rolle des GDNF bei der Organentwicklung entschlüsselt werden.
Exenatide‐induced hypomagnesaemia causing seizures
Authors: Kong M‐F , Nisal K
Published: August 2010

A 58‐year‐old Caucasian man with type 2 diabetes diagnosed in 1996 was started on exenatide (Byetta). His weight was 117kg and he had a body mass index (BMI) of 39kg/m2. He was taking 126 units of insulin per day with metformin. Previous attempts at weight loss had been unsuccessful. Over a period of six months, he lost 20kg in weight (BMI 30kg/m2). He reported nausea and vomiting, attributed to the exenatide, but because he was pleased with the weight loss he wanted to continue on exenatide. He had two episodes of witnessed generalised tonic–clonic seizures. He was teetotal and was not taking diuretics. He was found to be hypomagnesaemic with normal serum calcium and normal 24‐hour urinary magnesium excretion, excluding renal magnesium loss. It was concluded that his seizures were caused by nutritional hypomagnesaemia due to recurrent vomiting as a consequence of exenatide treatment. Copyright © 2010 John Wiley & Sons.
Consistency of a two clinical site sample collection: A proteomics study
Authors: Wiesner Cedric , Hannum Charles , Reckamp Karen , Figlin Robert , Dubridge Robert , Roy Sushmita Mimi , Lin Shanhua , Becker Christopher H. , Jones Ted , Hiller Jordan , Cheville John C. , Wilson Keith
Published: August 2010

Purpose: We investigated the ability to perform a clinical proteomic study using samples collected at different times from two independent clinical sites.

Experimental Design: Label‐free 2‐D‐LC‐MS proteomic analysis was used to differentially quantify tens of thousands of peptides from human plasma. We have asked whether samples collected from two sites, when analyzed by this type of peptide profiling, reproducibly contain detectable peptide markers that are differentially expressed in the plasma of disease (advanced renal cancer) patients relative to healthy normals.

Results: We have demonstrated that plasma proteins enriched in disease patients are indeed detected reproducibly in both clinical collections. Regression analysis, unsupervised hierarchical clustering and PCA detected no systematic bias in the data related to site of sample collection and processing. Using a genetic algorithm, support vector machine classification method, we were able to correctly classify disease samples at 88% sensitivity and 94% specificity using the second site as an independent validation set.

Conclusions and clinical relevance: We conclude that multiple site collection, when analyzed by label‐free 2‐D‐LC‐MS, generates data that are sufficiently reproducible to guide reliable biomarker discovery.
The Correlation between Electric Spark Sensitivity of Polynitroaromatic Compounds and Their Molecular Electronic Properties
Authors: Zhi Chunyan , Cheng Xinlu , Zhao Feng
Published: August 2010

In this paper, a relationship between electric spark sensitivity and molecular electronic properties is studied for polynitroaromatic compounds. The lowest unoccupied molecular orbital energy and the Mulliken charges of the nitro group, and the number of the aromatic rings as well as certain substituted groups attached to the aromatic ring can be used for the prediction of the electric spark sensitivity. Electric spark sensitivities calculated by such a correlation are reasonably close to the experimental data for both 17 polynitroaromatic explosives as training set and 11 polynitroaromatic explosives as test set.
How orientational order governs collectivity of folded proteins
Authors: Atilgan Canan , Okan Osman Burak , Atilgan Ali Rana
Published: August 2010

The past decade has witnessed the development and success of coarse‐grained network models of proteins for predicting many equilibrium properties related to collective modes of motion. Curiously, the results are usually robust toward the different cutoff distances used for constructing the residue networks from the knowledge of the experimental coordinates. In this study, we present a systematical study of network construction and their effect on the predicted properties. Probing bond orientational order around each residue, we propose a natural partitioning of the interactions into an essential and a residual set. In this picture, the robustness originates from the way with which new contacts are added, so that an unusual local orientational order builds up. These residual interactions have a vanishingly small effect on the force vectors on each residue. The stability of the overall force balance then translates into the Hessian as small shifts in the slow modes of motion and an invariance of the corresponding eigenvectors. We introduce a rescaled version of the Hessian matrix and point out a link between the matrix Frobenius norm based on spectral stability arguments and orientational local order. A recipe for the optimal choice of partitioning the interactions into essential and residual components is prescribed. Implications for the study of biologically relevant properties of proteins are discussed with specific examples. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Application of plant growth regulators mitigates chlorotic foliar injury by the black pecan aphid (Hemiptera: Aphididae)
Authors: Cottrell Ted E , Wood Bruce W , Ni Xinzhi
Published: August 2010

BACKGROUND: Black pecan aphid, Melanocallis caryaefoliae (Davis) (Hemiptera: Aphididae), feeding elicits localized chlorotic injury to pecan foliage [Carya illinoinensis (Wangenh.) K Koch] and apparent acceleration of leaf senescence and defoliation. The ability of certain plant growth regulators (PGRs) (forchlorfenuron, gibberellic acid and aviglycine) to prevent M. caryaefoliae from triggering pecan leaf chlorosis and senescence‐like processes was evaluated on two dates in both 2006 and 2007. Treatments were applied to orchard foliage and used in laboratory leaf‐disc bioassays to assess possible reduction in aphid‐elicited chlorosis and concomitant effects on aphid mortality and development.

RESULTS: Foliage pretreated with forchlorfenuron + gibberellic acid prior to being challenged with aphids resulted in significantly less aphid‐elicited chlorosis than did control or aviglycine‐treated leaf discs. No PGR affected aphid mortality; however, development time was increased by forchlorfenuron + gibberellic acid in 2006 and by aviglycine + gibberellic acid on one date in 2007.

CONCLUSION: Certain PGRs possess the potential for usage on pecan to protect foliar canopies from M. caryaefoliae via changes in the susceptibility of the host leaf to senescence‐like factors being introduced by feeding aphids. This protective effect on host foliage and the associated suppressive effect on development of feeding aphids might also be relevant to pest management programs on other aphid–crop systems in which aphid‐elicited chlorosis and senescence‐like processes can limit profitability. Published 2010 by John Wiley & Sons, Ltd.
Magnetic nanowires by electrodeposition within templates
Authors: Schlörb Heike , Haehnel Veronika , Khatri Manvendra Singh , Srivastav Ajeet , Kumar Amit , Schultz Ludwig , Fähler Sebastian
Published: August 2010

Magnetic nanowire arrays allow studying magnetism at the nanoscale and have broad application areas. Here we review our recent experiments on tailoring the structure and microstructure of electrochemically grown elemental (Fe, Ni, Co) and alloy (Co–Pt) magnetic nanowires. The comparison of these different materials allows identifying the role of shape, magnetocrystalline and magnetoelastic anisotropies as well as magnetostatic interactions.
Raman spectroscopy of graphene in different dielectric solvents
Authors: Klar Philipp , Casiraghi Cinzia
Published: August 2010

We have studied the effect of different dielectric environments on the properties of graphene by Raman spectroscopy. Graphene was produced by micromechanical exfoliation of graphite and deposited on a silicon substrate covered with 300 nm of silicon oxide (Si/SiO2). Graphene was immersed in water, ethanol and chloroform, which have a dielectric constant of 80, 30 and 4.8, at room temperature, respectively. We show that water immersion reduces the effect of charged impurities. Ethanol produces strong changes in the Raman spectrum. Graphene rolls and wrinkles once immersed in ethanol, as observed by optical microscope. Finally, chloroform produces a strong p‐doping as observed by the up‐shift of the G and 2D peaks. This shows that Raman spectroscopy is able to characterize the electrostatic environment of graphene (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the Ca2+ inhomogeneity distribution in the physical properties of La0.625Ca0.375MnO3
Authors: Piñeiro A. , Pardo V. , Baldomir D. , Rivadulla F. , Rodriguez A. , Gómez A. , Arias J. E. , Rivas J.
Published: August 2010

We report a study of the dopant distribution in the lattice of La1–xCaxMnO3, at concentration x = 0.375, in the ferromagnetic region of the phase diagram. The symmetry of the compound allows for four possible inequivalent Ca2+ distributions. We calculate within the LDA+U approximation (by full‐potential ab initio methods) the optimized geometries for each structure and the influence of the dopant homogeneity on the electronic structure of the material. We have analyzed the electronic structure for each of the distributions of Ca2+ considered, using the density of states and the partial Mn density of states. The system is half‐metallic for all configurations, due to the large Hund’s rule exchange on the Mn3+ cations. The analysis shows that the electronic structure remains largely in‐variant under different Ca2+ distributions in the lattice (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and characterisation of silica nanoparticles bearing different functional groups obtained via a two‐stage method
Authors: Berriozabal Gemma , de Miguel Yolanda R.
Published: August 2010

Silica nanoparticles with different functionalities (amine, nitrile, phenyl and vinyl) have been synthesised via a two‐stage method and characterised in depth. Analysis by TEM, DLS and AFM has shown that the sizes of these synthetic nanoparticles are mainly in the range of 60‐100 nm. In addition, 13C and 29Si CP/MAS NMR spectroscopy has been used to provide evidence of the presence of the organic functional groups. Finally, zeta potential measurements have been used to determine the stability of the colloidal dispersions in each case. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study on the effect of sol‐gel parameters on the size and morphology of silica microcapsules containing different organic compounds
Authors: Kaltzakorta Idurre , Erkizia Edurne
Published: August 2010

Efficient encapsulation of different compounds is an important research area for many industrial sectors such as food, cosmetic, medical and pharmaceutical industries [1]. Often these capsules are made up of organic materials. However, in recent years researchers have been focusing on the synthesis of inorganic capsules, and in particular, silica capsules due to their great chemical resistance, thermal stability, biocompatibility and their non‐toxic quality for the environment [2]. In this study silica capsules have been synthesized by combining the sol‐gel method with the emulsion process [3] and we have investigated how modifications in the synthesis parameters and even the nature of the encapsulated organic compound have an effect on the morphology, shell characteristics and the size distribution of the microcapsules (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Frequency‐ and polarization‐dependent optical response of asymmetric spheroidal silver nanoparticles on dielectric substrate
Authors: Mizeikis Vygantas , Kowalska Ewa , Ohtani Bunsho , Juodkazis Saulius
Published: August 2010

We report theoretical simulations of plasmonic near‐field enhancement and polarization in a system consisting of an asymmetric spheroidal Ag nanoparticle on a smooth dielectric surface. Finite‐difference time‐domain (FDTD) simulations reveal resonant optical extinction bands whose near‐field is concentrated at the metal–substrate contact point with intensity enhancement by a factor of 103 and predominant polarization along the normal to the surface. These features may help explain enhanced photo‐catalytic activity observed for colloidal Au and Ag nanoparticles on titania substrates.

magnified image

Electron microscopy image of Ag‐nanoparticles on titania and the used model for numerical FDTD simulations.

(© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In vitro protective effects of Withania somnifera (L.) dunal root extract against hydrogen peroxide and β‐amyloid(1–42)‐induced cytotoxicity in differentiated PC12 cells
Authors: Kumar S. , Seal C. J. , Howes M. J. R. , Kite G. C. , Okello E. J.
Published: August 2010

Withania somnifera L. Dunal (Solanaceae), also known as ‘ashwagandha’ in Sanskrit and as ‘Indian ginseng’, is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer, with antiaging, antistress, immunomodulatory and antioxidant properties. There is a paucity of data on the potential neuroprotective effects of W. somnifera root, as traditionally used, against H2O2‐ and Aβ(1–42)‐induced cytotoxicity which are current targets for novel approaches to treat dementia, especially dementia of the Alzheimer's type (AD). In this study, an aqueous extract prepared from the dried roots of W. somnifera was assessed for potential protective effects against H2O2‐ and Aβ(1–42)‐aggregated fibril cytotoxicity by an MTT assay using a differentiated rat pheochromocytoma PC12 cell line. The results suggest that pretreatments of differentiated PC12 cells with aqueous extracts of W. somnifera root significantly protect differentiated PC12 cells against both H2O2‐ and Aβ(1–42)‐induced cytotoxicity, in a concentration dependent manner. To investigate the compounds that could explain the observed effects, the W. somnifera extract was analysed by liquid chromatography–serial mass spectrometry and numerous withanolide derivatives, including withaferin A, were detected. These results demonstrate the neuroprotective properties of an aqueous extract of W. somnifera root and may provide some explanation for the putative ethnopharmacological uses of W. somnifera for cognitive and other neurodegenerative disorders that are associated with oxidative stress. Copyright © 2010 John Wiley & Sons, Ltd.
Revision of convection, radiation and cloud schemes in the ECMWF integrated forecasting system
Authors: Gregory D. , Morcrette J.‐J. , Jakob C. , Beljaars A. C. M. , Stockdale T.
Published: August 2010

Revisions to the convection, radiation and cloud schemes recently introduced into the European Centre for Medium‐Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS) are described, together with discussion of their impact upon model performance. Seasonal simulations with observed sea surface temperatures (SSTs) for June/July/August 1987 and December/January/February 1987/88 with a low‐resolution (T63) version of the model are used to assess the impact of the revised schemes, concentrating upon tropical climate and variability. While the revisions improve the physical basis of the schemes, and each improves aspects of the seasonal climate, overall improvement does not result until the changes are combined. Biases in simulated temperature and top‐of‐atmosphere and surface energy budgets are reduced, leading to a substantial decrease of an equatorial SST cold bias in coupled ocean‐atmosphere simulations used in seasonal forecasting. At higher resolution (T213) changes to temperature and wind fields are similar to those found in seasonal simulations, with little impact upon medium‐range forecast performance in mid latitudes, although these forecasts proved a more critical test of the impact of the schemes upon mid‐latitude flows. The paper demonstrates the methodology used in the development of parametrizations of physical processes at ECMWF, and points to the need to balance parametrization improvements especially between schemes which are highly interactive.
Multiple potential‐vorticity inversions in two FASTEX cyclones
Authors: Chaigne Emmanuel , Arbogast Philippe
Published: August 2010

This paper investigates pre‐existing synoptic‐scale disturbances responsible for cyclogenesis, using the manipulation of initial conditions through quasi‐geostrophic potential vorticity (QGPV) and its inversion. The use of a QGPV inversion together with a T63 model allows us to study the sensitivity of some FASTEX events to several QGPV patterns present within the analysis. It has been found that Ertel potential‐vorticity modifications of the analysis are preserved by the dynamical initialization process. The QGPV inversion method is applied to cyclones occurring in Intensive Observation Periods (IOPs) 11 and 12 of FASTEX (Fronts and Atlantic Storm‐Track EXperiment) to demonstrate which potential‐vorticity anomalies, present within the atmosphere prior to the development, are involved in the cyclogenesis. The choice of the boundary condition when an upper‐level precursor is removed from the initial conditions has little impact on the cyclone development. The linear interactions (advection/deformation of the anomaly by its environment and downstream development) between these upper‐level precursors and the surrounding flow dominate the dynamics of IOP11 cyclone development, whereas nonlinear processes are particularly strong in the IOP12 case. The cyclone development is only weakly sensitive to low‐level initial structures unless they are shaped like adjoint model sensitivities; collocation with another shape has little influence on the development.
Sources and sinks of climate entropy
Authors: Goody Richard
Published: August 2010

A satisfactory climate model must have similar sources and sinks of entropy to those of the atmosphere itself. This paper examines some of the theoretical and numerical issues involved in entropy sources and sinks. A balance equation is developed that involves a balance between entropy destruction by emission and absorption of radiation and entropy production by irreversible molecular processes. Estimating the thermal molecular source from turbulent enthalpy fluxes is shown to be consistent with the second law of thermodynamics only for free convection. Four entropy sources connected with the dissipation of kinetic energy are discussed. Moist convection is treated in terms of the mixing of warm/dry and cool/moist air masses. Questions are raised about the validity of treating latent heat as an external heat source acting upon a dry atmosphere. Theoretical estimates of entropy sources are compared with earlier estimates by Peixoto and others, and to the sources and sinks of entropy in a Goddard Institute of Space Studies climate control run. There are many discrepancies, particularly for moist convection. Our knowledge of atmospheric sources and sinks of entropy is evidently poor and, even if they were known, it would be difficult to construct a climate model with sources and sinks as precise as Johnson considers to be necessary.