bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cephalic modifications in dimorphic dwarf spiders of the genus oedothorax (Erigoninae, Linyphiidae, Araneae) and their evolutionary implications
Authors: Michalik Peter , Uhl Gabriele 
Published: April 2011

AbstractReproductive competition among males selects for a broad variety of strategies and traits from mate guarding to nuptial food gifts. Males of many dwarf spider species possess conspicuous secondary cephalic modifications, and the few studies available suggest that these cephalic structures are connected to extensive glandular tissue. Because females were observed to contact the male head structures during mating, these traits may have evolved in the context of sexual selection. We investigated the structure, glandular equipment, and sensory equipment of the cephalic regions of several species of the dwarf spider genus Oedothorax with varying degrees of sexual dimorphism using light and electron microscopy. In one Oedothorax species, there are two male morphs that exhibit a cephalic modification (O. gibbosus gibbosus) or not (O. gibbosus tuberosus). Our study demonstrates that all males investigated produce cephalic secretions, irrespective of the morphology of their cephalic region, however, they may differ in amount of secretion and in cellular organization. In males of O. apicatus,
O. gibbosus gibbosus and O. retusus the gland cells are very abundant in the area of a cephalic hump, whereas in the less conspicuous O. agrestis, and O. gibbosus tuberosus the gland cells are restricted to a small area behind the ocular region or include the ocular region as in O. fuscus. The glandular tissue consists of two gland types in O. agrestis, O. fuscus, O. gibbosus tuberosus and O. retusus and of only one type in O. apicatus and O. gibbosus gibbosus. The setae present on the head structure of all species seem to function as mechano‐ and/or chemoreceptors. The implications of our findings for the evolution of secretory head structures are discussed along with their potential for driving speciation. J. Morphol. 2011. © 2011Wiley‐Liss, Inc.
Label‐free sensing and atomic force spectroscopy for the characterization of protein–DNA and protein–protein interactions: application to estrogen receptors
Authors: Berthier A. , Elie‐Caille C. , Lesniewska E. , Delage‐Mourroux R. , Boireau W. 
Published: April 2011

AbstractIn this paper we describe a new surface plasmon resonance (SPR) biosensor dedicated to potential estrogenic compounds prescreening, by developing an estrogen receptor (ER) specific DNA chip. Through the covalent binding of a DNA strain wearing the estrogen response element (ERE) to an activated 6‐mercapto‐1‐hexadecanoic acid and 11‐mercapto‐1‐undecanol self‐assembled monolayer on gold surface, the SPR biosensor allows to detect specifically, quickly, and without any labeling the binding of ER in the presence of estrogen. In parallel, we investigated the ER interaction with itself, in order to study the formation of ER dimer apparently needed to activate the gene expression through ERE interaction. For that, we engaged force spectroscopy experiments that allowed us to prove that ER needs estrogen for its dimerization. Moreover, these ER/ER intermolecular measurements enabled to propose an innovative screening tool for anti‐estrogenic compounds, molecules of interest for hormono‐dependant cancer therapy. Copyright © 2011 John Wiley & Sons, Ltd.
Single and multiple bonds in (strept)avidin–biotin interactions
Authors: Teulon Jean‐Marie , Delcuze Yannick , Odorico Michael , Chen Shu‐wen W. , Parot Pierre , Pellequer Jean‐Luc 
Published: April 2011

AbstractThanks to Dynamic Force Spectroscopy (DFS) and developments of massive data analysis tools, such as YieldFinder, Atomic Force Microscopy (AFM) becomes a powerful method for analyzing long lifetime ligand–receptor interactions. We have chosen the well‐known system, (strept)avidin–biotin complex, as an experimental model due to the lack of consensus on interpretations of the rupture force spectrum (Walton et al., 2008). We present new measurements of force–displacement curves for the (strept)avidin–biotin complex. These data were analyzed using the YieldFinder software based on the Bell‐Evans formalism. In addition, the Williams model was adopted to interpret the bonding state of the system. Our results indicate the presence of at least two energy barriers in two loading rate regimes. Combining with structural analysis, the energy barriers can be interpreted in a novel physico‐chemical context as one inner barrier for H‐bond ruptures (γ < 1 Å), and one outer barrier for escaping from the binding pocket which is blocked by the side chain of a symmetry‐related Trp120 in the streptavidin tetramer. In each loading rate regime, the presence of multiple parallel bonds was implied by the Williams model. Interestingly, we found that in literature different terms created for addressing the apparent discrepancies in the results of avidin–biotin interactions can be reconciled by taking into account multiple parallel bonds. Copyright © 2011 John Wiley & Sons, Ltd.
Structure and assembly–disassembly properties of wild‐type transthyretin amyloid protofibrils observed with atomic force microscopy
Authors: Pires Ricardo H. , Saraiva Maria J. , Damas Ana M. , Kellermayer Miklós S. Z. 
Published: April 2011

AbstractTransthyretin (TTR) is an important human transport protein present in the serum and the cerebrospinal fluid. Aggregation of TTR in the form of amyloid fibrils is associated with neurodegeneration, but the mechanisms of cytotoxicity are likely to stem from the presence of intermediate assembly states. Characterization of these intermediate species is therefore essential to understand the etiology and pathogenesis of TTR‐related amyloidoses. In the present work we used atomic force microscopy to investigate the morphological features of wild‐type (WT) TTR amyloid protofibrils that appear in the early stages of aggregation. TTR protofibrils obtained by mild acidification appeared as flexible filaments with variable length and were able to bind amyloid markers (thioflavin T and Congo red). Surface topology and contour‐length distribution displayed a periodic pattern of ∼15 nm, suggesting that the protofibrils assemble via an end‐binding oligomer fusion mechanism. The average height and periodic substructure found in protofibrils is compatible with the double‐helical model of the TTR amyloid protofilament. Over time protofibrils aggregated into bundles and did not form mature amyloid‐like fibrils. Unlike amyloid fibrils that are typically stable under physiological conditions, the bundles dissociated into component protofibrils with axially compacted and radially dilated structure when exposed to phosphate‐buffered saline solution. Thus, WT TTR can form metastable filamentous aggregates that may represent an important transient state along the pathway towards the formation of cytotoxic TTR species. Copyright © 2011 John Wiley & Sons, Ltd.
Parallel AFM imaging and force spectroscopy using two‐dimensional probe arrays for applications in cell biology
Authors: Favre Mélanie , Polesel‐Maris Jérôme , Overstolz Thomas , Niedermann Philippe , Dasen Stephan , Gruener Gabriel , Ischer Réal , Vettiger Peter , Liley Martha , Heinzelmann Harry , Meister André 
Published: April 2011

AbstractAtomic force microscopy (AFM) investigations of living cells provide new information in both biology and medicine. However, slow cell dynamics and the need for statistically significant sample sizes mean that data collection can be an extremely lengthy process. We address this problem by parallelizing AFM experiments using a two‐dimensional cantilever array, instead of a single cantilever. We have developed an instrument able to operate a two‐dimensional cantilever array, to perform topographical and mechanical investigations in both air and liquid. Deflection readout for all cantilevers of the probe array is performed in parallel and online by interferometry. Probe arrays were microfabricated in silicon nitride. Proof‐of‐concept has been demonstrated by analyzing the topography of hard surfaces and fixed cells in parallel, and by performing parallel force spectroscopy on living cells. These results open new research opportunities in cell biology by measuring the adhesion and elastic properties of a large number of cells. Both properties are essential parameters for research in metastatic cancer development. Copyright © 2011 John Wiley & Sons, Ltd.
The use of lipid microtubes as a novel slow‐release delivery system for laryngeal injection
Authors: Kolachala Vasantha L. , Berg Eric E. , Shams Samantha , Mukhatyar Vivek , Sueblinvong Viranuj , Bellamkonda Ravi V. , Johns Michael M. 
Published: April 2011

AbstractObjectives/Hypothesis:The potential utility of direct injection of bioactive substances in the treatment of vocal fold tissue fibrosis is limited by rapid clearance from the injection site. The objective of this study is to evaluate the potential of a lipid‐based microtube delivery system to preserve the biological activity of injected substances and prolong their duration of pharmacological effects in the larynx.Study Design:Prospective in vitro and case–control in vivo murine studyMethods:Lipid‐based microtubes were loaded with Texas red‐dextran (MT‐TR) and hepatocyte growth factor (MT‐HGF). In vitro and in vivo (using a murine vocal fold injection model) release of MT‐TR and MT‐HGF were determined to assess duration of microtube‐mediated delivery. The biologic effects of MT‐HGF on fibroblasts were assessed after treatment in the presence of transforming growth factor (TGF)‐β.Results:In vitro release kinetics demonstrated slow release of MT‐TR and MT‐HGF, correlating with in vivo results demonstrating persistence of MT‐HGF at 4 weeks postinjection. Bioefficacy was maintained, as MT‐HGF was shown to inhibit TGF‐β‐mediated induction of procollagen mRNA levels in vitro 24 hours after treatment in fibroblast cells. Sustained release of HGF from microtubes at 6 days exacerbated the effects of TGF‐β and increased levels of procollagen mRNA.Conclusions:Microtubes have significant potential utility as an efficacious means of sustained‐release delivery of bioactive agents to the larynx. Atthough the role of HGF as an antifibrotic agent is questioned, its sustained bioefficacy after microtube encapsulation distinguishes microtubes from other delivery vehicles.
Steroid therapy may be effective in augmenting hemoglobin levels during hemolytic crises in children with hereditary spherocytosis
Authors: Ballin Ami , Waisbourd‐Zinman Orit , Saab Hitam , Yacobovich Joanne , Zoldan Meirah , Barzilai‐Birenbaum Shlomit , Yaniv Isaac , Tamary Hannah 
Published: April 2011

AbstractBackgroundThe course of hereditary spherocytosis (HS) may be subject to hemolytic episodes, sometimes requiring blood transfusion. The aim of this study was to evaluate the efficacy of a short course of steroid therapy in elevating hemoglobin levels during hemolytic crisis.ProcedureThe files of all patients followed for HS from 1968 to 2009 at our hospital were reviewed. Outcome of hemolytic crises was compared between steroid‐treated and untreated patients; patients given packed red blood cell transfusion(s) or erythropoietin treatment were excluded. A good outcome was defined as an increase of at least 20% in hemoglobin level from the nadir within 1 week.ResultsOf the 118 patients with HS who attended our hospital during the study period, 20 were treated with steroids and 9 received no treatment. Mean nadir hemoglobin level in both groups was 6.9 g/dl. The study group had a total of 50 steroid‐treated hemolytic crises of which 37 (74%) responded favorably to treatment. Treatment failure was significantly associated with a low dose (<1 mg/kg/day) or short duration (<1 week) of treatment. The nine untreated patients had 16 hemolytic crises, of which 25% had a good outcome. Steroid therapy was significantly more effective than no therapy in increasing hemoglobin level (P = 0.015) in these hemolytic crises.ConclusionSteroid therapy may be effective in augmenting hemoglobin levels during hemolytic crises in patients with moderate HS and eventually will result in a reduced need for RBC transfusion. Pediatr Blood Cancer 2011; 57: 303–305. © 2011 Wiley‐Liss, Inc.
Protein loop selection using orientation‐dependent force fields derived by parameter optimization
Authors: Liang Shide , Zhang Chi , Standley Daron M. 
Published: April 2011

AbstractWe used the orientation‐dependent Optimized Side Chain Atomic eneRgy (OSCAR‐o), derived in an early study, for protein loop selection. The prediction accuracy of OSCAR‐o was better than that of physics‐based force fields or statistical potential energy functions for both the RAPPER decoy set and the Jacobson decoy set. The native conformer was frequently ranked as lowest energy among the decoys. Furthermore, strong correlation was observed between the OSCAR‐o score and the root mean square deviation (RMSD) from the native structure for energy‐minimized decoys. In practical use, we applied OSCAR‐o to rescore decoys generated by a widely used loop‐modeling program, LOOPY. As a result, the mean RMSD values of top‐ranked decoys were reduced by 0.3 Å for loop targets of seven to nine residues. We expect similar performance for OSCAR‐o with other loop‐modeling algorithms in the context of decoy rescoring. A loop selection program (OSCAR‐ls) based on OSCAR‐o is available at http://sysimm.ifrec.osaka‐u.ac.jp/OSCAR/. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Contact and fumigant toxicity of plant essential oils and efficacy of spray formulations containing the oils against B‐ and Q‐biotypes of Bemisia tabaci
Authors: Kim Soon‐Il , Chae Song‐Hwa , Youn Hee‐Sung , Yeon Seong‐Hum , Ahn Young‐Joon 
Published: April 2011

AbstractBACKGROUND: The contact + fumigant toxicity of 92 plant essential oils and control efficacy of 18 experimental spray formulations containing nine selected essential oils (0.5 and 0.1% sprays) and six commercial insecticides to females from B‐ and Q‐biotypes of Bemisia tabaci were evaluated using vapour‐phase mortality and spray bioassays.RESULTS: Garlic and oregano (LC50, 0.15 mL cm−3) were the most toxic oils against B‐ and Q‐biotype females. Strong fumigant toxicity to both biotype females was also obtained from catnip, cinnamon bark, clove bud, clove leaf, davana, savory and vetiver Haiti oils (LC50, 0.17–0.48 mL cm−3). The 0.5% sprays of these oils (except for thyme red oil) resulted in 90–100% mortality against both biotype females. Only garlic applied as 0.1% spray provided 100% mortality. Spinosad 100 g L−1 suspension concentrate (SC) treatment resulted in 92 and 95% mortality against both biotype females, whereas acetamiprid 80 g L−1 wettable powder (WP), imidacloprid 80 g L−1 SC, thiamethoxam 100 g L−1 water‐dispersible granule (WDG) and pyridaben 200 g L−1 WP treatments resulted in 89–100% mortality against B‐biotype females only.CONCLUSION: In the light of global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment, the essential oils described, particularly garlic, cinnamon bark and vetiver Haiti, merit further study as potential insecticides for the control of B. tabaci populations as fumigants with contact action. Copyright © 2011 Society of Chemical Industry
Drip application of methyl bromide alternative chemicals for control of soilborne pathogens and weeds
Authors: Gerik James S , Hanson Bradley D 
Published: April 2011

AbstractBACKGROUND: Producers of several high‐value crops in California have traditionally used preplant soil fumigation with methyl bromide/chloropicrin combinations. Although methyl bromide has been phased out since 2005, several crop industries, including cut flower producers, have continued methyl bromide use under Critical Use Exemptions, a provision of the Montreal Protocol. This research was conducted to evaluate newer, emerging methyl bromide alternative chemicals.RESULTS: Two field trials were conducted to test several emerging chemicals in combination with metam sodium as replacements for methyl bromide. Emerging chemicals included 2‐bromoethanol, dimethyl disulfide, furfural, propylene oxide and sodium azide. Weed and pathogen populations were measured after chemical application, and seed viability was assessed from weed seed previously buried in the plots. In the first trial, the emerging chemicals did not improve pest control compared with metam sodium alone. However, in the second trial, several of these chemicals did improve the pest control performance of metam sodium.CONCLUSIONS: The emerging alternative chemicals have the potential to provide better control of soilborne pathogens and weeds when used with metam sodium than metam sodium alone. Registration of these materials could provide California growers with a broader choice of tools compared with the limited methyl bromide alternatives now available. Published 2011 by John Wiley & Sons, Ltd.
Hot carrier relaxation process in InGaN epilayers
Authors: Lagarde D. , Carrère H. , Chassaing P.‐M. , Balocchi A. , Marie X. , Balkan N. , Schaff W. J. 
Published: April 2011

AbstractInGaN epilayers with gallium fractions ranging between 0 and 0.48 have been studied by time‐resolved photoluminescence. Layers containing low gallium fractions are associated with low PL emission intensity. For In0.83Ga0.17N layer, the luminescence decay is 100 times faster in the high energy part of the photoluminescence spectrum than on the low energy part, reflecting the hot carrier recombination process. This is confirmed by the significant blue shift of the photoluminescence spectra for short decay times compared to the time integrated spectrum. It takes about 10 ps for the carriers to reach an equilibrium temperature of 100 K.
Nanoneedles based on porous silicon for chip bonding with self assembly capability
Authors: Jonnalagadda Prasad , Mescheder Ulrich , Kovacs Andras , Nimoe Antwi 
Published: April 2011

AbstractNeedle‐like surface structures have been fabricated using a self‐organized nanostructuring process based on porous silicon. Optimized surfaces have been used for a novel bonding process in Si‐MEMS. The realized needle‐like surfaces enable Van‐der‐Waals based bonding at low temperature with self‐assembly capability. The bonding forces depend on the surface topology and can be tailored by the nanostructuring process between permanent and detachable bonding. Bond strength for permanent bonding in the range of 1‐10 MPa has been achieved. Multiple bonding of the same surface is possible (Velcro®‐principle). The capability of needle like surfaces for self aligned bonding of Si‐chips or small silicon based systems (“smart dust”) on locally nanostructured areas of silicon wafers (Si‐motherboard) has been shown. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐linear conductivity of NbS3 in pressure induced metal state
Authors: Dizhur Eugene , Kostyleva Irina , Voronovskii Anatoly , Zaitzev‐Zotov Sergey 
Published: April 2011

AbstractTemperature and voltage dependencies of conduction of a quasi‐one‐dimensional conductor NbS3 after its transition into a metallic state has been studied at pressures higher than 6 GPa. The differential resistance R = dV /dI measured at small biases (the electric field E below 2 V/cm) demonstrate a considerable growth upon cooling below 20 K accompanied by appearance of the non‐linear conduction.Both the growth and nonlinear conduction disappear at E > 3 V/cm or when the temperature exceeds 40 K. A narrow dip visible only at much smaller fields E < 20 mV/cm is superimposed over that nonlinear background when cooling below 3.7 K. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Compressibility and vibration modes of the supramolecular compound assembly from arsenic vanadates and [Co(H2O)6]2+ cations
Authors: Han Dandan , Hong Youliang , Ma Yanmei , Wang Xin , Zhu Pinwen 
Published: April 2011

AbstractThe high‐pressure behavior of new supramolecular compound based on arsenic vanadates formulated as [H2As6V15O42(H2O)][Co(H2O)6]2.2H2O is investigated by Raman spectroscopy using a diamond anvil cell up to 21GPa. A reversible pressure‐induced phase transition was observed at a pressure above 8.3 GPa. Upon compression, the intensity of modes at lower‐frequency from 100‐600 cm‐1V1, V2, V3, V4, softens and vanishes at about 8.3 GPa. Also, the high‐frequency v7(937cm‐1) disappears at about 8.3 GPa. The reversible transition may be due to both the extinct of vanadyl(V=O) double bonds in VO5 pyramids and the changes in the AsO3 network under pressure. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Formulation and in vitro evaluation of κ‐carrageenan‐pregelatinized starch‐based mucoadhesive gels containing miconazole
Authors: Lefnaoui Sonia , Moulai‐Mostefa Nadji 
Published: April 2011

AbstractThe aim of this work was to investigate the effects of using κ‐carrageenan (κ‐Carr) with pregelatinized starch (PGS) in the improvement of swelling and erosion behaviors of mucoadhesive gels containing 2% of miconazole. Polymer blends containing carrageenan and PGS were used for the formulation, and the effect of varying polymer concentrations on the drug release was studied. The matrices were prepared using different biopolymer (starch hydrogel) concentrations. Swelling and erosion characteristics of the matrices were carried out in various media and their impact on drug release were studied. The swelling action of the gel matrix was controlled by the rate of its hydration in the medium. Release studies have showed that the swelling and erosion of matrices influence the drug release. In addition, the presence of κ‐Carr in the gel formula improves the bioadhesive properties. The release data showed a good fit into the power law or Korsmeyer–Peppas equation indicating the combined effects of diffusion and erosion mechanisms of drug release. Most of the formulations released miconazole by an anomalous (non‐Fickian) transport mechanism, except those matrices that contained PGS alone which showed zero‐order release.
Anion Effects on the Formation of Silver(I) Complexes with the Flexible Ligand 4,4′‐Bis(1,2,4‐triazol‐1‐ylmethyl)biphenyl
Authors: Ni Tianjun , Zhao Yongmei , Shao Min , Zhu Shourong , Xing Feifei , Li Mingxing 
Published: April 2011

AbstractThe reaction of 4,4′‐bis(1,2,4‐triazol‐1‐ylmethyl)biphenyl (btmb) with silver(I) salts of BF4–, NO3– and N3– led to the formation of four new silver(I) coordination polymers {[Ag(btmb)]BF4}n (1), {[Ag2(btmb)3](NO3)2(H2O)5}n (2), [Ag2(btmb)(N3)2]n (3), and [Ag(btmb)(N3)]n (4). Their coordination number varies from 2 (in 1) to 3 (in 2), 4 (in 3), and 5 (in 4). Different from the single chain structure of 1, complex 2 displays a 1D ladder‐like double chain framework, whereas complex 3 exhibits a 2D layered architecture. Complex 4 has the same anion as complex 3 but shows a different metal‐to‐ligand ratio and a 1D double‐zigzag chain structure. Both 3 and 4 have Ag···Ag argentophilic interactions. The ligand btmb adopts both cis or trans configuration in the studied complexes. A trans‐ or cis‐btmb ligand link silver ions with Ag···Ag distances of ≈︁18 and 13 Å, respectively. BF4– and NO3– are non‐coordinating anions in 1 and 2. N3– is the bridging anion in 3 (1,3‐bridging fashion) and 4 (1,1‐bridging fashion). These findings suggest that the coordination numbers around the AgI ion correlate to the coordination abilities of anions and the btmb to silver ratio. In addition, the influence of anions on thermal stability were also investigated. This work is a good example that nicely supports the less explored field of anion‐dependent structures of complexes with non‐pyridyl ligands.