bluuebunny/crossref_metadata_2025 huggingface dataset:
Multimerization of Peptide Mimotopes for Blocking of Factor VIII Neutralizing Antibodies
Authors: Kessel Christoph , Kreuz Wolfhart , Klich Katharina , Becker‐Peters Karin , Vorpahl Frank , Dietrich Ursula , Klingebiel Thomas , Königs Christoph
Published: June 2009

About 30 % of patients with severe hemophilia A develop neutralizing antibodies (inhibitors) to coagulation factor VIII (FVIII) upon treatment with exogenous factor preparations. Two peptides, C6 (NPVENMMDRDSQ) and H10 (QSPWQTWFTRAL), that mimic putative inhibitor epitopes (mimotopes), were previously selected by phage display screening of plasma samples from patients with inhibitors. Synthetic peptide mimotopes inhibited IgG binding to FVIII (IC50: 30–50 μM). This effect was increased by an equimolar combination of both mimotopes. Mimotopes were fused to the C‐terminal multimerization domain of the C4bp α‐chain and expressed as multimers in 293T cells. Multimerized mimotopes showed improved binding to anti‐FVIII IgG and prolonged in vitro half‐life relative to synthetic peptides. The two mimotopes were combined in heteromultimers by co‐transfection of 293T cells with respective vectors, resulting in bi‐specific molecules that almost completely blocked polyclonal antibody binding to FVIII (IC50: 2–3 μM). This strategy is capable of functionally improving synthetic peptides by multimerization and could provide a basis for novel therapeutic approaches for patients with hemophilia A and inhibitors.
PAMAM Dendrimers Mediate siRNA Delivery to Target Hsp27 and Produce Potent Antiproliferative Effects on Prostate Cancer Cells
Authors: Liu Xiao‐xuan , Rocchi Palma , Qu Fan‐qi , Zheng Shu‐quan , Liang Zi‐cai , Gleave Martin , Iovanna Juan , Peng Ling
Published: June 2009

RNA interference (RNAi) holds great promise for the treatment of inherited and acquired diseases, provided that safe and efficient delivery systems are available. Herein we report that structurally flexible triethanolamine (TEA) core PAMAM dendrimers are able to deliver an Hsp27 siRNA effectively into prostate cancer (PC‐3) cells by forming stable nanoparticles with siRNA, protecting the siRNA nanoparticles from enzymatic degradation, and enhancing cellular uptake of siRNA. The Hsp27 siRNA resulted in potent and specific gene silencing of heat‐shock protein 27, an attractive therapeutic target in castrate‐resistant prostate cancer. Silencing of the hsp27 gene led to induction of caspase‐3/7‐dependent apoptosis and inhibition of PC‐3 cell growth in vitro. In addition, the siRNA–dendrimer complexes are non‐cytotoxic under the conditions used for siRNA delivery. Altogether, TEA core PAMAM dendrimer‐mediated siRNA delivery, in combination with RNAi that specifically targets Hsp27, may constitute a promising approach for combating castrate‐resistant prostate cancer, for which there is no efficacious treatment.
The integration of corporate governance in corporate social responsibility disclosures
Authors: Kolk Ans , Pinkse Jonatan
Published: June 2009

In recent years, not only has attention to corporate governance increased but also the notion has broadened considerably, and started to cover some aspects traditionally seen as being part of corporate social responsibility (CSR). CSR, corporate governance and their interlink seem particularly relevant for multinational enterprises (MNEs), which, due to their activities in multiple contexts around the world and concomitant visibility, generally face higher demands to be transparent and disclose information about such issues. Insights into whether and in which cases disclosures on the two topics actually merge has been very limited, however. This paper analyses to what extent corporate governance has become integrated in MNEs' disclosure practices on CSR. Based on an analysis of CSR reporting of Fortune Global 250 companies, findings show that more than half of them have a separate corporate governance section in their CSR report and/or explicitly link corporate governance and CSR issues. We also found that MNEs that disclose information on a wider variety of social and environmental issues and frame CSR with a focus on internal issues are more inclined to integrate corporate governance into their CSR reporting. This integration seems to be a global phenomenon that cuts across countries and sectors. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Towards Molecular Wires Based on Metal‐Organic Frameworks
Authors: Mas‐Ballesté Rubén , Castillo Oscar , Sanz Miguel Pablo J. , Olea David , Gómez‐Herrero Julio , Zamora Félix
Published: June 2009

The formation of one‐dimensional structures on nanoscale is one of the main goals of modern nanotechnology. The aim of these efforts is to find conductive long molecules that could serve as molecular wires in nanocircuits. In recent years, electrical conductivity in several organic and metal‐organic systems has been studied to this end. In principle, DNA is one of the most attractive molecules for molecular wire owing to its well‐known self‐assembly chemistry and controllable structural diversity. However, the ability of DNA to conduct electricity is still controversial. In principle, binding of metal ions to organic molecules seems to be a suitable method for improving conductivity. Therefore, some studies were carried out with the so‐called M‐DNA as an alternative to increase conductivity on DNA. We have selected the 1D‐coordination polymer [Cd(6‐MP–)2]n (6‐MP– = 6‐mercaptopurinate) as a feasible structural model that is suitable for providing basic information about the electrical properties of M‐DNA.Work with this coordination polymer revealed several aspects concerning the systematic search for new adsorption methods for coordination polymers on surfaces, their morphological and physical characterization, and opened a new playground for the study of coordination polymers as potential molecular wires. In this microreview, we focus on the description of several methods dealing with the isolation of single chains from crystals of these supramolecules, and different pathways to obtain molecular assemblies are also described. Methodologies and characterization techniques are illustrated with the results obtained with different coordination polymers.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Crystal Structure, Vibrational Spectra and Activation of BaCa(P4O12) with Eu2+ Compared with β‐Sr(PO3)2:Eu
Authors: Höppe Henning A. , Panzer J. Michel U.
Published: June 2009

The polyphosphates β‐Sr(PO3)2 and BaCa(PO3)4 were doped with Eu2+, BaCa(PO3)4 was structurally characterised for the first time. Both phosphors were analysed by fluorescence spectroscopy. β‐Sr(PO3)2:Eu and BaCa(PO3)4:Eu were found to emit blue light at 424 nm and 418 nm, respectively, with a broader emission band compared with α‐Sr(PO3)2:Eu. Both phosphors can be excited at 330 nm, i.e. an UV‐LED emission. The crystal structure of BaCa(PO3)4 has been determined based on single‐crystal data [P21/n, Z = 4, a = 723.00(11), b = 917.05(19), c = 1524.7(2) pm, β = 90.995(12)°, R1 = 0.050, wR2 = 0.099, 1748 reflections, 164 parameters]. BaCa(PO3)4 is not homeotypic with β‐Sr(PO3)2 and α‐Sr(PO3)2 but isotypic with BaCd(PO3)4. The vibrational spectra of BaCa(PO3)4 are also presented and discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
New Electrochemically Generated Polymeric Pd Complexes as Heterogeneous Catalysts for Suzuki Cross‐Coupling Reactions
Authors: Bandini Marco , Pietrangelo Agostino , Sinisi Riccardo , Umani‐Ronchi Achille , Wolf Michael O.
Published: June 2009

Electrochemically generated films of polymerized (diamino‐oligothiophene)palladium complexes as heterogeneous catalysts for Suzuki cross‐coupling reactions are reported. The electrodeposition of these polymeric species onto porous graphite electrodes allows for easy removal of the organometallic species from the reaction mixture and convenient reuse in subsequent (up to 6) reactions.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
First Asymmetric Synthesis of (Un)saturated 1‐Alkylbenzo[c]azepin‐3‐ones: Extension to the Corresponding Benzazepines
Authors: Dumoulin David , Lebrun Stéphane , Deniau Eric , Couture Axel , Grandclaudon Pierre
Published: June 2009

A flexible route for the stereoselective synthesis of a variety of structurally diverse (1R)‐1‐alkyldihydro and tetrahydrobenzazepin(ones) has been developed. The key step is a highly diastereoselective 1,2‐addition process applied to a stereopure aromatic hydrazone combined with a ring‐closing metathesis reaction to secure the formation of the seven‐membered azaheterocycle ring system.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Efficient and Selective Method for the Synthesis of Dihydrodipyridopyrazines Based on the Pd‐Catalysed Amination of Halopyridines
Authors: Patriciu Oana‐Irina , Fînaru Adriana‐Luminiţa , Massip Stéphane , Léger Jean‐Michel , Jarry Christian , Guillaumet Gérald
Published: June 2009

A novel methodology for the efficient and selective synthesis of isomers A and B of N‐substituted dihydrodipyridopyrazines was developed. The key step is the intermolecular coupling of aminopyridines and halonitropyridines/dihalopyridines in the presence of a catalyst system composed of Pd(OAc)2/Xantphos. This system displays good functional group compatibility and the desired C–N bond‐forming process proceeds in good yields. Cyclization of suitable nitro‐substituted N,N′‐dipyridinylamines produces monosubstituted dihydrodipyridopyrazines, which can easily be alkylated to give a large variety of unsymmetrical 5,10‐dialkyl‐5,10‐dihydrodipyrido[2,3‐b:2′,3′‐e]pyrazines (isomers A) and 5,10‐dialkyl‐5,10‐dihydrodipyrido[2,3‐b:3′,2′‐e]pyrazines (isomers B). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis of C‐1 Alkyl and Aryl Glycals from Pyranosyl or Furanosyl Chlorides by Treatment with Organolithium Reagents
Authors: Gómez Ana M. , Pedregosa Ana , Casillas Marta , Uriel Clara , López J. Cristóbal
Published: June 2009

Glycosyl chlorides, with ether or isopropylidene acetal protecting groups, readily available from furanoses or pyranoses, can be conveniently transformed into C‐1 alkyl or aryl glycals by reaction with alkyl or aryl organolithium reagents. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Alkoxyallene‐Based De Novo Synthesis of Rare Deoxy Sugars: New Routes to L‐Cymarose, L‐Sarmentose, L‐Diginose and L‐Oleandrose
Authors: Brasholz Malte , Reißig Hans‐Ulrich
Published: June 2009

Starting from lithiated methoxyallene and lactaldehyde derivatives, the four rare 2,6‐dideoxy‐hexoses L‐cymarose, L‐sarmentose, L‐diginose and L‐oleandrose were synthesized in a stereodivergent fashion. Key steps towards these four target monosaccharides were the oxidative ring openings of allene‐derived 2,5‐dihydrofurans, diastereoselective carbonyl reductions as well as face‐selective hydrogenation protocols. First glycosylation reactions employing thiophenyl glycosyl donors of L‐cymarose and L‐diginose were performed in high yields and with fair to excellent stereocontrol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Influence of rock mass strength on the erosion rate of alpine cliffs
Authors: Moore Jeffrey R. , Sanders Johnny W. , Dietrich William E. , Glaser Steven D.
Published: June 2009

Collapse of cliff faces by rockfall is a primary mode of bedrock erosion in alpine environments and exerts a first‐order control on the morphologic development of these landscapes. In this work we investigate the influence of rock mass strength on the retreat rate of alpine cliffs. To quantify rockwall competence we employed the Slope Mass Rating (SMR) geomechanical strength index, a metric that combines numerous factors contributing to the strength of a rock mass. The magnitude of cliff retreat was calculated by estimating the volume of talus at the toe of each rockwall and projecting that material back on to the cliff face, while accounting for the loss of production area as talus buries the base of the wall. Selecting sites within basins swept clean by advancing Last Glacial Maximum (LGM) glaciers allowed us to estimate the time period over which talus accumulation occurred (i.e. the production time). Dividing the magnitude of normal cliff retreat by the production time, we calculated recession rates for each site. Our study area included a portion of the Sierra Nevada between Yosemite National Park and Lake Tahoe. Rockwall recession rates determined for 40 alpine cliffs in this region range from 0·02 to 1·22 mm/year, with an average value of 0·28 mm/year. We found good correlation between rockwall recession rate and SMR which is best characterized by an exponential decrease in erosion rate with increasing rock mass strength. Analysis of the individual components of the SMR reveals that joint orientation (with respect to the cliff face) is the most important parameter affecting the rockwall erosion rate. The complete SMR score, however, best synthesizes the lithologic variables that contribute to the strength and erodibility of these rock slopes. Our data reveal no strong independent correlations between rockwall retreat rate and topographic attributes such as elevation, aspect, or slope angle. Copyright © 2009 John Wiley & Sons, Ltd.
Optimised spreading code redistribution PAPR reduction technique for MC‐CDMA systems
Authors: Yang Lin , Alsusa Emad
Published: June 2009

Multicarrier code division multiple access (MC‐CDMA) is one of the most promising techniques considered for future broadband mobile services. However, the high peak to average power ratio (PAPR) problem associated with MC‐CDMA systems can significantly degrade the power efficiency at the transmitter. This paper proposes an efficient PAPR reduction technique for the downlink of MC‐CDMA systems. It regards the order of the CDMA spreading codes as an extra degree of freedom and exploits it to effectively reduce the PAPR of the signal. The proposed technique requires only slight modification to the MC‐CDMA base station and negligible complexity to the mobile terminals. Both lightly loaded and fully loaded systems are examined when using the orthogonal sets of Walsh—Hadamard (WH) and Golay complementary sequences (CSs). It will be demonstrated that the proposed technique achieves significant PAPR reduction with low system complexity at both transmitter and receiver. Copyright © 2009 John Wiley & Sons, Ltd.
Slip effects on the peristaltic flow of a Jeffrey fluid in an asymmetric channel under the effect of induced magnetic field
Authors: Nadeem S. , Akram Safia
Published: June 2009

In the present study, we investigated the effects of slip and induced magnetic field on the peristaltic flow of a Jeffrey fluid in an asymmetric channel. The governing two‐dimensional equations for momentum, magnetic force function and energy are simplified by using the assumptions of long wavelength and low but finite Reynolds number. The reduced problem has been solved by Adomian decomposition method (ADM) and closed form solutions have been presented. Further, the exact solution of the proposed problem has also been computed and the mathematical comparison shows that both solutions are almost similar. The effects of pertinent parameters on the pressure rise per wavelength are investigated using numerical integration. The expressions for pressure rise, friction force, velocity, temperature, magnetic force function and the stream lines against various physical parameters of interest are shown graphically. Moreover, the behavior of different kinds of wave shape are also discussed. Copyright © 2009 John Wiley & Sons, Ltd.
The putative heme transporter HCP1 is expressed in cultured astrocytes and contributes to the uptake of hemin
Authors: Dang Theresa N. , Bishop Glenda M. , Dringen Ralf , Robinson Stephen R.
Published: June 2009

Hemin, which is toxic to brain cells, has been reported to be taken up by cultured astrocytes; however, the mechanism of uptake is currently unknown. The present study investigated the mechanism of hemin uptake by rat primary astrocyte cultures. In medium containing 10% fetal calf serum, cultured astrocytes failed to accumulate significant amounts of heme‐iron, while in serum‐free medium the accumulation of heme‐iron was found to be time‐ and concentration‐dependent. After 6 h of incubation with 24 μM hemin, cells contained 36.2 ± 2.4 nmol heme‐iron/mg protein, which was 21% of the applied hemin. These results suggest that the accumulation of hemin in astrocytes does not require serum proteins such as hemopexin. A potential mechanism of hemin uptake in astrocytes involves the heme carrier protein 1 (HCP1), which is reported to mediate hemin uptake into intestinal cells. RT‐PCR analysis revealed that astrocyte cultures contained HCP1 mRNA, and immunocytochemical staining and Western blot analysis confirmed the expression of HCP1 protein in cultured astrocytes. The functionality of HCP1 in astrocytes was demonstrated by incubating cells with zinc protoporphyrin IX (ZnPPIX), which is known to be transported into cells via HCP1, and ZnPPIX autofluorescence was detected in HCP1‐positive astrocytes. In addition, ZnPPIX was found to attenuate the accumulation of heme‐iron by astrocytes. These results are the first to demonstrate that cultured astrocytes contain functional HCP1 and that this transporter contributes to hemin uptake by astrocytes. HCP1 may therefore provide a new target for reducing hemin‐related toxicity in brain cells. © 2009 Wiley‐Liss, Inc.
Hippocampal synaptic transmission and LTP in vivo are intact following bilateral vestibular deafferentation in the rat
Authors: Zheng Yiwen , Mason‐Parker Sara E. , Logan Barbara , Darlington Cynthia L. , Smith Paul F. , Abraham Wickliffe C.
Published: June 2009

Numerous studies in animals and humans have shown that damage to the vestibular system in the inner ear results in spatial memory deficits, presumably because areas of the brain such as the hippocampus require vestibular input to accurately represent the spatial environment. Consistent with this hypothesis, studies in animals have demonstrated that complete bilateral vestibular deafferentation (BVD) causes a disruption of place cell firing as well as theta activity. The aim of this study was to investigate whether BVD in rats affects baseline field potentials (field excitatory postsynaptic potentials and population spikes) and long‐term potentiation (LTP) in CA1 and the dentate gyrus (DG) of awake freely moving rats up to 43 days post‐BVD and of anesthetized rats at 7 months post‐BVD. Compared to sham controls, BVD had no significant effect on either baseline field potentials or LTP in either condition. These results suggest that although BVD interferes with the encoding, consolidation, and/or retrieval of spatial memories and the function of place cells, these changes are not related to detectable in vivo decrements in basal synaptic transmission or LTP, at least in the investigated pathways. © 2009 Wiley‐Liss, Inc.
β‐Adrenergic receptors link NO/sGC/PKG signaling to BDNF expression during the consolidation of object recognition long‐term memory
Authors: Furini Cristiane R. , Rossato Janine I. , Bitencourt Lucas L. , Medina Jorge H. , Izquierdo Iván , Cammarota Martín
Published: June 2009

The nitric oxide (NO)/soluble guanylyl cyclase (sGC)/protein kinase G (PKG) pathway is important for memory processing, but the identity of its downstream effectors as well as its actual participation in the consolidation of nonaversive declarative long‐term memory (LTM) remain unknown. Here, we show that training rats in an object recognition (OR) learning task rapidly increased nitrites/nitrates (NOx) content in the CA1 region of the dorsal hippocampus while posttraining intra‐CA1 microinfusion of the neuronal NO synthase (nNOS) inhibitor L‐NN hindered OR LTM retention without affecting memory retrieval or other behavioral variables. The amnesic effect of L‐NN was not state dependent, was mimicked by the sGC inhibitor LY83583 and the PKG inhibitor KT‐5823, and reversed by coinfusion of the NO donorS‐nitroso‐N‐acetylpenicillamine (SNAP) and the PKG activator 8‐bromoguanosine 3′,5′‐cyclic monophosphate (8Br‐cGMP). SNAP did not affect the amnesic effect of LY83583 and KT‐5823. Conversely, 8Br‐cGMP overturned the amnesia induced by LY83583 but not that caused by KT‐5823. Intra‐CA1 infusion of the β‐adrenergic receptor blocker timolol right after training hindered OR LTM and, although coadministration of noradrenaline reversed the amnesia caused by L‐NN, LY83583, and KT5823, the amnesic effect of timolol was unaffected by coinfusion of 8Br‐cGMP or SNAP, indicating that hippocampal β‐adrenergic receptors act downstream NO/sGC/PKG signaling. We also found that posttraining intra‐CA1 infusion of function‐blocking anti‐brain‐derived neurotrophic factor (BDNF) antibodies hampered OR LTM retention, whereas OR training increased CA1 BDNF levels in a nNOS‐ and β‐adrenergic receptor‐dependent manner. Taken together, our results demonstrate that NO/sGC/PKG signaling in the hippocampus is essential for OR memory consolidation and suggest that β‐adrenergic receptors link the activation of this pathway to BDNF expression during the consolidation of declarative memories. © 2009 Wiley‐Liss, Inc.
A re‐examination of the stationarity of inflation
Authors: Cook Steven
Published: June 2009

In a recent examination of the integrated nature of inflation, Culver and Papell (Journal of Applied Econometrics, 1997) applied a range of unit root and stationarity tests to data from a panel of 13 OECD economies. The results obtained were mixed. While little evidence of stationarity was detected using univariate methods, rejection of the unit root hypothesis was observed under panel data unit root testing, although rejection was found to be sensitive to cross‐sectional variation. In this note the results of Culver and Papell are reconsidered in light of conditional heteroskedasticity detected in the inflation rate series. Using a more appropriate univariate testing procedure combining local‐to‐unity detrending and joint maximum likelihood estimation of a unit root testing equation and GARCH process, strong evidence in favour of stationarity is detected in 11 of 13 economies examined. In contrast to the univariate findings of Culver and Papell, the results obtained herein using an alternative univariate procedure provide evidence in support of their I(0) inference drawn using panel methods. Copyright © 2009 John Wiley & Sons, Ltd.
Neurobehavioral toxicity study of dibutyl phthalate on rats followingin uteroand lactational exposure
Authors: Li Yuanfeng , Zhuang Meizhu , Li Tao , Shi Nian
Published: June 2009

To investigate the neurobehavioral effects of dibutyl phthalate (DBP), an important endocrine disruptor known for reproductive toxicity, on rodent offspring followingin uteroand lactational exposure, pregnant Wistar rats were treated with DBP (0, 0.037, 0.111, 0.333 and 1% in the diet) from gestation day (GD) 6 to postnatal day (PND) 28, and selected developmental and neurobehavioral parameters of the offspring were measured. There were no significant effects of DBP on body weight gain of the dams during GD 6–20 or on the pups' ages of pinna detachment, incisor eruption or eye opening. Exposure to 1% DBP prolonged gestation period, decreased body weight in both male and female pups, depressed surface righting (PND 7) in male pups, shortened forepaw grip time (PND 10), enhanced spatial learning and reference memory (PND 35) in male pups. Exposure to 0.037% DBP also shortened forepaw grip time (PND 10), but inhibited spatial learning and reference memory in male pups. Sex × treatment effects were found in forepaw grip time (PND 10), spatial learning and reference memory, and the male pups appeared to be more susceptible than the females. However, all levels of DBP exposure did not significantly alter surface righting (PND 4), air righting (PND 16), negative geotaxis (PND 4 or 7), cliff avoidance (PND 7) or open field behavior (PND 28) in either sex. Overall, the dose level of DBP in the present study produced a few adverse effects on the neurobehavioral parameters, and it may alter cognitive abilities of the male rodent. Copyright © 2009 John Wiley & Sons, Ltd.
Shift of oxidants and antioxidants levels in rats as a reaction to exposure to sulfur mustard
Authors: Pohanka Miroslav , Stetina Rudolf
Published: June 2009

Antixodants as well as oxidants levels were investigated in plasma of rats exposed to sulfur mustard in doses of 0 (control), 5, 20 and 80 mg kg−1body weight. Cyclic voltammetry performed on screen‐printed strips with platinum working electrode used as a tool for assaying oxidant and antioxidant levels. We found significant shifts in both examined analytes. A dose of sulfur mustard of 5 mg kg−1body weight caused only a small change in oxidant and antioxidant levels when compared with the control group. A dose of 20 mg kg−1body weight provided a significant increase in antioxidants as well oxidants; however, the ratio of both was similar to that in the control group. The most surprising facts were found when the highest dose of 80 mg kg−1body weight of sulfur mustard was applied. While antioxidants were significantly increased, oxidants were decreased on an extensive scale. Copyright © 2009 John Wiley & Sons, Ltd.
Doppler calibration method for Spectral Domain OCT spectrometers
Authors: Faber Dirk J. , Leeuwen Ton G. van
Published: June 2009

We present a calibration method for SD‐OCT domain spectrometers based on the M‐scan of a moving mirror. This method allows determination of the wavenumber sampling increment which determines the depth axis assigned to the structural image. It also allows wavelength calibration of individual pixels which ensures correct re‐sampling prior to Fast Fourier Transform. Determination of the spectrometer resolution, which determines sensitivity and resolution decay with depth, is also possible. The wavelength calibration results suggest that hardware calibration of the spectrometers is a necessary complement to the computational methods presented here. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
KiSS1 suppresses TNFα‐induced breast cancer cell invasion via an inhibition of RhoA‐Mediated NF‐κB activation
Authors: Cho Sung‐Gook , Li Dali , Stafford Lewis J. , Luo Jian , Rodriguez‐Villanueva Melissa , Wang Ying , Liu Mingyao
Published: June 2009

Tumor necrosis factor‐alpha (TNFα) induces cancer development and metastasis, which is prominently achieved by nuclear factor‐kappa B (NF‐κB) activation. TNFα‐induced NF‐κB activation enhances cellular mechanisms including proliferation, migration, and invasion. KiSS1, a key regulator of puberty, was initially discovered as a tumor metastasis suppressor. The expression of KiSS1 was lost or down‐regulated in different metastatic tumors. However, it is unclear whether KiSS1 regulates TNFα‐induced NF‐κB activation and further tumor cell migration. In this study, we demonstrate that KiSS1 suppresses the migration of breast cancer cells by inhibiting TNFα‐induced NF‐κB pathway and RhoA activation. Both KiSS1 overexpression and KP10 (kisspeptin‐10) stimulation inhibited TNFα‐induced NF‐κB activity, suppressed TNFα‐induced cell migration and cell attachment to fibronectin in breast cancer cells while KP10 has little effect on cancer cell proliferation. Furthermore, KP10 inhibited TNFα‐induced cell migration and RhoA GTPase activation. Therefore, our data demonstrate that KiSS1 inhibits TNFα‐induced NF‐κB activation via downregulation of RhoA activation and suppression of breast cancer cell migration and invasion. J. Cell. Biochem. 107: 1139–1149, 2009. © 2009 Wiley‐Liss, Inc.
Src and FAK mediate cell–matrix adhesion‐dependent activation of met during transformation of breast epithelial cells
Authors: Hui Angela Y. , Meens Jalna A. , Schick Colleen , Organ Shawna L. , Qiao Hui , Tremblay Eric A. , Schaeffer Erik , Uniyal Shashi , Chan Bosco M.C. , Elliott Bruce E.
Published: June 2009

Cell–matrix adhesion has been shown to promote activation of the hepatocyte growth factor receptor, Met, in a ligand‐independent manner. This process has been linked to transformation and tumorigenesis in a variety of cancer types. In the present report, we describe a key role of integrin signaling via the Src/FAK axis in the activation of Met in breast epithelial and carcinoma cells. Expression of an activated Src mutant in non‐neoplastic breast epithelial cells or in carcinoma cells was found to increase phosphorylation of Met at regulatory tyrosines in the auto‐activation loop domain, correlating with increased cell spreading and filopodia extensions. Furthermore, phosphorylated Met is complexed with β1 integrins and is co‐localized with vinculin and FAK at focal adhesions in epithelial cells expressing activated Src. Conversely, genetic or pharmacological inhibition of Src abrogates constitutive Met phosphorylation in carcinoma cells or epithelial cells expressing activated Src, and inhibits filopodia formation. Interestingly, Src‐dependent phosphorylation of Met requires cell–matrix adhesion, as well as actin stress fiber assembly. Phosphorylation of FAK by Src is also required for Src‐induced Met phosphorylation, emphasizing the importance of the Src/FAK signaling pathway. However, stimulation of Met phosphorylation by addition of exogenous HGF in epithelial cells is refractory to inhibition of Src family kinases, indicating that HGF‐dependent and Src/integrin‐dependent Met activation occur via distinct mechanisms. Together these findings demonstrate a novel mechanism by which the Src/FAK axis links signals from the integrin adhesion complex to promote Met activation in breast epithelial cells. J. Cell. Biochem. 107: 1168–1181, 2009. © 2009 Wiley‐Liss, Inc.
Characterization of myostatin/gdf8/11 in the starlet sea anemone Nematostella vectensis
Authors: Saina Michael , Technau Ulrich
Published: June 2009

The signaling molecule Myostatin, a member of the TGF‐β superfamily, is crucially involved in the control of muscle growth and development in triploblastic organisms. A homolog to vertebrate myostatin and gdf8/11 was isolated from a diploblastic cnidarian, the starlet sea anemone Nematostella vectensis. Here we provide a detailed characterization of the Nematostella myostatin/gdf8/11 gene and show the first analysis of gene expression in adult polyps. This analysis revealed that myostatin/gdf8/11 is expressed in the mesenteries, which are endodermal folds, and weakly in the body wall endoderm, but largely excluded from the areas of muscle formation, the retractor and the parietal muscle. Contrary to this, in vertebrates the muscle growth inhibitor myostatin is expressed in the muscle tissue. We therefore hypothesize that myostatin/gdf8/11 in Nematostella is involved in regulating nonmuscle cell differentiation, possibly by repressing muscle differentiation. J. Exp. Zool. (Mol. Dev. Evol.) 312B:780–788, 2009. © 2009 Wiley‐Liss, Inc.
Specific inhibition of epithelial Na+ channels by antisense oligonucleotides for the treatment of Na+ hyperabsorption in cystic fibrosis
Authors: Sobczak Katja , Segal Andrei , Bangel‐Ruland Nadine , Semmler Judith , Van Driessche Willy , Lindemann Hermann , Heermann Ralf , Weber Wolf‐Michael
Published: June 2009

Background

Cystic fibrosis (CF) respiratory epithelia are characterized by a defect Cl− secretion and an increased Na+ absorption through epithelial Na+ channels (ENaC). The present study aimed to find an effective inhibitor of human ENaC with respect to replacing amiloride therapy for CF patients. Therefore, we developed specific antisense oligonucleotides (AON) that efficiently suppress Na+ hyperabsorption by inhibiting the expression of the α‐ENaC subunit.

Methods

We heterologously expressed ENaC in oocytes of Xenopus laevis for mass screening of AON. Additionally, primary cultures of human nasal epithelia were transfected with AON and were used for Ussing chamber experiments, as well as biochemical and fluorescence optical analyses.

Results

Screening of several AON by co‐injection or sequential microinjection of AON and ENaC mRNA in X. laevis oocytes led to a sustained decrease in amiloride‐sensitive current and conductance. Using primary cultures of human nasal epithelia, we show that AON effectively suppress amiloride‐sensitive Na+ absorption mediated by ENaC in CF and non‐CF tissues. In western blot experiments, it could be shown that the amount of ENaC protein is effectively reduced after AON transfection.

Conclusions

Our data comprise an initial step towards a preclinical test with AON to reduce Na+ hyperabsorption in CF epithelia. Copyright © 2009 John Wiley & Sons, Ltd.
Immunogenicity of intrathecal plasmid gene delivery: cytokine release and effects on transgene expression
Authors: Hughes Travis S. , Langer Stephen J. , Virtanen Salla I. , Chavez Raymond A. , Watkins Linda R. , Milligan Erin D. , Leinwand Leslie A.
Published: June 2009

Background

One method for the delivery of therapeutic proteins to the spinal cord is to inject nonviral gene vectors including plasmid DNA into the cerebrospinal fluid (CSF) that surrounds the spinal cord (intrathecal space). This approach has produced therapeutic benefits in animal models of disease and several months of protein expression; however, there is little information available on the immune response to these treatments in the intrathecal space, the relevance of plasmid CpG sequences to any plasmid‐induced immune response, or the effect of this immune response on transgene expression.

Methods

In the present study, coding or noncoding plasmids were delivered to the intrathecal space of the lumbar spinal region in rats. Lumbosacral CSF was then collected at various time points afterwards for monitoring of cytokines and transgene expression.

Results

This work demonstrates, for the first time, increased tumor necrosis factor‐α and interleukin‐1 in response to intrathecal plasmid vector injection and provides evidence indicating that this response is largely absent in a CpG‐depleted vector. Transgene expression in the CSF is not significantly affected by this immune response. Expression after intrathecal plasmid injection is variable across rats but correlates with the amount of tissue associated plasmid and is increased by disrupting normal CSF flow.

Conclusions

The data obtained in the present study indicate that plasmid immunogenicity may affect intrathecal plasmid gene therapy safety but not transgene expression in the CSF. Furthermore, the development of methods to prevent loss of plasmid via CSF flow out of the central nervous system through the injection hole and/or natural outflow routes may increase intrathecal plasmid gene delivery efficacy. Copyright © 2009 John Wiley & Sons, Ltd.
Sulfoglucuronosyl paragloboside is a ligand for T cell adhesion: Regulation of sulfoglucuronosyl paragloboside expression via nuclear factor κB signaling
Authors: Dasgupta Somsankar , Silva Jeane , Wang Guanghu , Yu Robert K.
Published: June 2009

Inflammatory cytokines such as tumor necrosis factor (TNF)‐α and interleukin (IL)‐1β stimulate glucuronosyltransferase genes (S and P) in endothelial cells (ECs) and up‐regulate sulfoglucuronosyl paragloboside (SGPG) expression, which serves as a ligand for T cell adhesion. However, the mechanism of cytokine‐mediated gene up‐regulation has not been elucidated. To evaluate the precise mechanism of SGPG up‐regulation, we have specifically inhibited the SGPG synthesis in the cerebromicrovascular EC line (SV‐HCECs), a transformed brain ECs of human origin. SV‐HCECs were transfected with small interfering RNA designed to mimic the human natural killer epitope‐1 sulfotransferase (HNK‐1ST), the ultimate enzyme that transfers the sulfate group to glucuronic acid for SGPG synthesis. An inhibition of SGPG expression along with a reduction of human CD4+ cell adhesion was observed in siRNA HNK‐1ST (siHNK‐1)‐transfected cells after TNFα stimulation. A thorough screening of the signaling system confirmed that TNFα/IL‐1β stimulation up‐regulated nuclear factor κB (NFκB) signaling in SV‐HCECs. siHNK‐1 transfection interfered with the SGPG up‐regulation after TNFα/IL‐1β stimulation in transfected cells and reduced the T cell adhesion. Hence, our study indicates that T cell‐SGPG adhesion in SV‐HCECs may proceed through NFκB activation. In addition, siHNK‐1 transfection reduced the NFκB activity compared with cells that were transfected with scrambled siRNA, before and after TNFα/IL‐1β stimulation. This is the first report indicating that NFκB signaling is involved in SGPG gene expression in brain ECs by an unknown mechanism. Its down‐regulation by inhibiting HNK‐1ST expression may have a potential use in preventing the T cell invasion and consequently nerve damage during inflammation. © 2009 Wiley‐Liss, Inc.
Expression and distribution of cystic fibrosis transmembrane conductance regulator in neurons of the spinal cord
Authors: Guo Yong , Su Min , Su Meng , McNutt Michael A. , Gu Jiang
Published: June 2009

To verify the hypothesis that cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in neurons of the human spinal cord, we investigated the presence and distribution of CFTR protein and mRNA in different segments of the human spinal cord obtained from autopsies. The techniques employed included reverse transcriptase‐polymerase chain reaction (RT‐PCR) to detect CFTR gene expression, in situ hybridization to detect mRNA distribution, and immunohistochemistry to detect protein distribution. The specificity of these experiments was established with extensive controls. We found widespread and abundant expression of CFTR in neurons of the human spinal cord. CFTR protein and mRNA are localized to the cytoplasm of neurons in all segments of the spinal cord but not to glial fibrillary acidic protein (GFAP)‐positive cells. CFTR is a very important molecule, acting as a chloride channel and regulating many physiological functions, including salt transport, fluid flow, and intracellular ion concentrations. Its mutation causes cystic fibrosis. Our finding of abundant CFTR in the spinal cord suggests that this molecule may be significant in the normal function and pathology of the spinal cord. © 2009 Wiley‐Liss, Inc.
Fustin flavonoid attenuates β‐amyloid (1–42)‐induced learning impairment
Authors: Jin Chun‐Hui , Shin Eun‐Joo , Park Jae‐Bong , Jang Choon‐Gon , Li Zhengyi , Kim Min Soo , Koo Kyo Hwan , Yoon Hyoung‐Jong , Park Sang‐Jae , Choi Won‐Cheol , Yamada Kiyofumi , Nabeshima Toshitaka , Kim Hyoung‐Chun
Published: June 2009

Natural flavonoids ameliorate amyloid‐β peptide (Aβ)‐induced neurotoxicity. We examined whether the fustin flavonoid affects Aβ‐induced learning impairment in mice. Repeated treatment with fustin significantly attenuated Aβ (1–42)‐induced conditioned fear and passive avoidance behaviors. This effect was comparable to that of EGb761, a standard extract of ginkgo. Fustin treatment significantly prevented decreases in acetylcholine (ACh) levels, choline acetyltransferase (ChAT) activity, and ChAT gene expression induced by Aβ (1–42). Fustin also consistently suppressed increases in acetyl cholinesterase (AChE) activity and AChE gene expression induced by Aβ (1–42). In addition, fustin significantly attenuated Aβ (1–42)‐induced selective decreases in muscarinic M1 receptor gene expression and muscarinic M1 receptor binding activity (as determined by [3H]pirenzepine binding) by modulating extracellular signal‐regulated kinase 1/2 (ERK 1/2) and cAMP response‐element binding protein (CREB) phosphorylation and brain‐derived neurotrophic factor (BDNF) expression. These effects of fustin were reversed by treatment with dicyclomine, a muscarinic M1 receptor antagonist, and SL327, a selective ERK inhibitor, but not by chelerythrine, a pan‐protein kinase C (PKC) inhibitor. Taken together, our results suggest that fustin attenuates Aβ (1–42)‐impaired learning, and that the ERK/CREB/BDNF pathway is important for the M1 receptor‐mediated cognition‐enhancing effects of fustin. © 2009 Wiley‐Liss, Inc.
Baseline articular contact stress levels predict incident symptomatic knee osteoarthritis development in the MOST cohort
Authors: Segal Neil A. , Anderson Donald D. , Iyer Krishna S. , Baker Jennifer , Torner James C. , Lynch John A. , Felson David T. , Lewis Cora E. , Brown Thomas D.
Published: June 2009

We studied whether contact stress estimates from knee magnetic resonance images (MRI) predict the development of incident symptomatic tibiofemoral osteoarthritis (OA) 15 months later in an at‐risk cohort. This nested case‐control study was conducted within a cohort of 3,026 adults, age 50 to79 years. Thirty cases with incident symptomatic tibiofemoral OA by their 15 month follow‐up visit were randomly selected and matched with 30 control subjects. Symptomatic tibiofemoral OA was defined as daily knee pain/stiffness and Kellgren‐Lawrence Grade ≥2 on weight bearing, fixed‐flexion radiographs. Tibiofemoral geometry was segmented on baseline knee MRI, and contact stresses were estimated using discrete element analysis. Linear mixed models for repeated measures were used to examine the association between articular contact stress and case/control status. No significant intergroup differences were found for age, sex, BMI, weight, height, or limb alignment. However, the maximum articular contact stress was 0.54 ± 0.77 MPa (mean ± SD) higher in incident OA cases compared to that in control knees (p = 0.0007). The interaction between case‐control status and contact stress was significant above 3.20 MPa (p < 0.0001). The presence of differences in estimated contact stress 15 months prior to incidence suggests a biomechanical mechanism for symptomatic tibiofemoral OA and supports the ability to identify risk by subject‐specific biomechanical modeling. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1562–1568, 2009
Changes in total and labile carbon and nitrogen contents in a sandy soil after the conversion of a succession fallow to cultivated land
Authors: Böhm Christian , Landgraf Dirk , Makeschin Franz
Published: June 2009

The content of soil organic matter (SOM) can be considered as an important factor for evaluating soil fertility, crop yields, and environmental effects. Sensitive measurements for the assessment of quantitative changes in SOM shortly after the conversion of the management practice would be helpful to understand the SOM‐transformation cycle in more detail. Changes in SOM are reflected in modifications of total organic‐carbon (TOC) and total organic‐nitrogen (TON) contents. They are initially detectable in the readily decomposable fraction. We used hot water–extractable carbon (HWC) and nitrogen (HWN) as measurement of labile pools of SOM and aimed to quantify changes in contents of these C and N fractions in a sandy soil already few years after changing management strategy. In this context, we examined the impact of the conversion of a succession fallow (F) to organic (O) and intensive (I) agriculture on TOC, total N (TN), HWC, and HWN. The conversion of succession fallow to cultivated land resulted in a significant decrease of TOC, TN, and HWC at 0–10 cm soil depth. On average, TOC decreased approx. 0.70 g C kg–1 (approx. 9% of initial TOC), TN decreased approx. 0.13 g N kg–1 (approx. 17% of initial TN), and HWC decreased approx. 0.05 g C kg–1 (approx. 12% of initial HWC) within 3 years. Relatively rapid changes in TOC and TN contents indicated comparatively high proportions of decomposable C and N. These were reflected in comparable high HWC (ranging from 0.37 to 0.59 g C kg–1 at 0–30 cm soil depth) and HWN (ranging from 0.04 to 0.10 g N kg–1 at 0–30 cm) contents. These high contents as well as the high HWC : TOC and organic hot water–extractable N (HWNorg) : TN ratios (both between 5% and 7%) implied that the soil investigated has a high ability to provide short‐term available organic C and N compounds. Long‐lasting applications of high quantities of organic fertilizer in the past and high quantities of rhizodepositions were assumed as reasons for the high capability of soil to provide short‐term to medium‐term available C and N. Changes in the HWN content due to the fertilization or crop rotation were mainly based on changes in its inorganic part. This ranged between 10% and 30% of HWN. By discriminant function analysis, it could be shown that the HWN represents a suitably sensitive measurement for the determination of management‐specific impacts in terms of the N, but also of the C cycle. In combination with other C and particularly with other N parameters, the HWN allowed a statistically significant separation of comparable sites varying in management practice already 2 years after the conversion of the management system.
Determination of the fate of regularly applied13C‐labeled‐artificial‐exudates C in two agricultural soils
Authors: Marx Marc , Buegger Franz , Gattinger Andreas , Zsolnay Ádám , Charles Munch Jean
Published: June 2009

Exudates are part of the total rhizodeposition released by plant roots to soil and are considered as a substantial input of soil organic matter. Exact quantitative data concerning the contribution of exudates to soil C pools are still missing. This study was conducted to reveal effects of13C‐labeled exudate (artificial mixture) which was regularly applied to upper soil material from two agricultural soils. The contribution of exudate C to water‐extractable organic C (WEOC), microbial biomass C (MBC), and CO2‐C evolution was investigated during a 74 d incubation. The WEOC, MBC, and CO2‐C concentrations and the respective δ13C values were determined regularly. In both soils, significant incorporation of artificial‐exudate‐derived C was observed in the WEOC and MBC pool and in CO2‐C. Up to approx. 50% of the exudate‐C amounts added were recovered in the order WEOC << MBC < CO2‐C in both soils at the end of the incubation. Newly built microbial biomass consisted mainly of exudates, which substituted soil‐derived C. Correspondingly, the CO2‐C evolved from exudate‐treated soils relative to the controls was dominated by exudate C, showing a preferential mineralization of this substrate. Our results suggest that the remaining 50% of the exudate C added became stabilized in non‐water‐extractable organic fractions. This assumption was supported by the determination of the total organic C in the soils on the second‐last sampling towards the end of the incubation. In the exudate‐treated soils, significantly more soil‐derived C compared to the controls was found in the WEOC on almost all samplings and in the MBC on the first sampling. This material might have derived from exchange processes between the added exudate and the soil matrix. This study showed that easily available substrates can be stabilized in soil at least in the short term.