bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of activin A synthesis in microglial cells: Pathophysiological implications for bacterial meningitis
Authors: Wilms Henrik , Schwark Thorsten , Brandenburg Lars‐Ove , Sievers Jobst , Dengler Reinhard , Deuschl Günther , Lucius Ralph 
Published: August 2009

AbstractPrevious studies have shown that activin A, a neuroprotective cytokine and dimeric polypeptide composed of two βA subunits, is elevated in the cerebrospinal fluid of patients suffering from bacterial meningitis. In this study, to elucidate further the functional significance and pathophysiological implications of these findings, we demonstrated that microglial cells are not only the source but also the target cells of activin A in the central nervous system: immunohistochemistry and RT‐PCR revealed expression of activin subunit βA mRNA as well as activin receptor type I and type II mRNA in rat microglia in vitro. Further studies showed that activin enhances microglial proliferation and decreases the γ‐interferon‐induced synthesis of nitric oxide, one of several microglial mediators involved in the inflammatory response in microglia activation. Furthermore, quantitative RT‐PCR, Western blotting, and ELISA showed an inhibitory effect of activin on inducible nitric oxide synthase, tumor necrosis factor‐α, interleukin‐6, and interleukin‐1β gene and protein levels after lipopolysaccharide treatment. We suggest that the increased synthesis of activin A is directly involved, via influence on microglia cell functions, in the modulation of the inflammatory response in bacterial meningitis. © 2009 Wiley‐Liss, Inc.
Melatonin treatment potentiates neurodegeneration in a rat rotenone Parkinson's disease model
Authors: Tapias Victor , Cannon Jason R. , Greenamyre J. Timothy 
Published: August 2009

AbstractParkinson's disease (PD) is characterized pathologically by progressive neurodegeneration of the nigrostriatal dopamine (DA) system. Currently, the cause of the disease is unknown, except for a small percentage of familial cases (<10% of total). The rat rotenone model reproduces many of the pathological features of the human disease, including apomorphine‐responsive behavioral deficits, DA depletion, loss of striatal DA terminals and nigral dopaminergic neurons, and α‐synuclein/polyubiquitin‐positive cytoplasmic inclusions reminiscent of Lewy bodies. Therefore, this model is well‐suited to examine potential neuroprotective agents. Melatonin is produced mainly by the pineal gland and is known primarily for regulating circadian rhythms. It also has potent free radical scavenging and antiinflammatory properties. Melatonin has been reported to be neuroprotective in the 6‐hydroxydopamine (6‐OHDA) and 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) models of PD. However, there are conflicting reports suggesting that melatonin does not provide neuroprotection in these models. Melatonin elicits significant functional changes in the nigrostriatal DA system that may affect 6‐OHDA and MPTP entry into cells. Therefore, rotenone is an ideal model for assessing protection, because it does not rely on the dopamine transporter uptake to exert neurotoxicity. In this study, the neuroprotective potential of melatonin in the rotenone PD model was assessed. Melatonin potentiated striatal catecholamine depletion, striatal terminal loss, and nigral DA cell loss. Indeed, melatonin alone elicited alterations in striatal catecholamine content. Our findings indicate that melatonin is not neuroprotective in the rotenone model of PD and may exacerbate neurodegeneration. © 2009 Wiley‐Liss, Inc.
A tephrostratigraphic record for the last glacial–interglacial cycle from Lake Ohrid, Albania and Macedonia
Authors: Vogel Hendrik , Zanchetta Giovanni , Sulpizio Roberto , Wagner Bernd , Nowaczyk Norbert 
Published: August 2009

AbstractHere we present a tephrostratigraphic record (core Co1202) recovered from the northeastern part of Lake Ohrid (Republics of Macedonia and Albania) reaching back to Marine Isotope Stage (MIS) 6. Overall ten horizons (OT0702‐1 to OT0702‐10) containing volcanic tephra have been recognised throughout the 14.94 m long sediment succession. Four tephra layers were visible at macroscopic inspection (OT0702‐4, OT0702‐6, OT0702‐8 and OT0702‐9), while the remaining six are cryptotephras (OT0702‐1, OT0702‐2, OT0702‐3, OT0702‐5, OT0702‐7 and OT0702‐10) identified from peaks in K, Zr and Sr intensities, magnetic susceptibility measurements, and washing and sieving of the sediments. Glass shards of tephra layers and cryptotephras were analysed with respect to their major element composition, and correlated to explosive eruptions of Italian volcanoes. The stratigraphy and the major element composition of tephra layers and cryptotephras allowed the correlation of OT0702‐1 to AD 472 or AD 512 eruptions of Somma‐Vesuvius, OT0702‐2 to the FL eruption of Mount Etna, OT0702‐3 to the Mercato from Somma‐Vesuvius, OT0702‐4 to SMP1‐e/Y‐3 eruption from the Campi Flegrei caldera, OT0702‐5 to the Codola eruption (Somma‐Vesuvius or Campi Flegrei), OT0702‐6 to the Campanian Ignimbrite/Y‐5 from the Campi Flegrei caldera, OT0702‐7 to the Green Tuff/Y‐6 eruption from Pantelleria Island, OT0702‐8 to the X‐5 eruption probably originating from the Campi Flegrei caldera, OT0702‐9 to the X‐6 eruption of generic Campanian origin, and OT0702‐10 to the P‐11 eruption from Pantelleria Island. The fairly well‐known ages of these tephra layers and parent eruptions provide new data on the dispersal and deposition of these tephras and, furthermore, allow the establishment of a chronological framework for core Co1202 for a first interpretation of major sedimentological changes. Copyright © 2009 John Wiley & Sons, Ltd.
Ion‐Selective Optodes Measure Extracellular Potassium Flux in Excitable Cells
Authors: Harjes Daniel I. , Dubach J. Matthew , Rosenzweig Anthony , Das Saumya , Clark Heather A. 
Published: August 2009

AbstractOptodes have been used for detection of ionic concentrations and fluxes for several years. However, their uses in biomedical applications have not yet been fully explored. This study investigates optodes as a potential sensor platform for monitoring cellular ion flux with attendant implications in the field of drug screening and toxicology. A prototype system was developed to quantitatively measure extracellular potassium flux from a monolayer of cardiomyocytes. Optodes were created and immobilized on a glass coverslip for fluorescent imaging. The system detected potassium (K+) ion flux during the repolarization phase of the cardiac action potential and further detected a decrease in the magnitude of the flux in the presence of a known K+ channel inhibitor by optically monitoring local K+ ion concentrations during field stimulation of the cardiomyocyte monolayer.magnified image
Influence of PEG‐ran‐PPG Surfactant on Vapour Phase Polymerised PEDOT Thin Films
Authors: Fabretto Manrico , Müller Michael , Zuber Kamil , Murphy Peter 
Published: August 2009

AbstractThe oxidant, Fe(III) tosylate, was used in the vapour phase polymerisation (VPP) of PEDOT. The amphiphilic co‐polymer poly(ethylene glycol‐ran‐propylene glycol) was added and its influence examined. Both the PEDOT conductivity and optical contrast range increased with the inclusion of the co‐polymer, with the maximum being recorded at 4 wt.‐%. Loadings higher than this resulted in a systematic decrease in both conductivity and optical contrast. Evidence indicates that in addition to the beneficial anti‐crystallisation effect to the oxidant layer, the co‐polymer also reduces the effective reactivity of the oxidant, as demonstrated by slower polymerisation rates. Confirmation of the change in polymerisation rate was obtained using a quartz crystal microbalance (QCM). The slower polymerisation rate results in higher conductivity and optical contrast; however, XPS data confirmed that the co‐polymer remained within the PEDOT film post‐washing and this result explains why the performance decreases at high surfactant loadings.magnified image
Discoidin domain receptor 2 (DDR2) is required for maintenance of spermatogenesis in male mice
Authors: Kano Kiyoshi , Kitamura Ayami , Matsuwaki Takashi , Morimatsu Masami , Naito Kunihiko 
Published: August 2009

AbstractDiscoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase (RTK). We recently identified homozygous smallie mutant mice (BKS.HRS. Ddr2slie/slie/J, Ddr2slie/slie mutants), which lack a functional DDR2. Ddr2slie/slie mutant mice are dwarfed and infertile due to peripheral dysregulation of the endocrine system. To understand the role of DDR2 signaling in spermatogenesis, we studied the expression of several receptors, enzymes, and proteins related to spermatogenesis in wild‐type and Ddr2slie/slie mutant mice at 10 weeks and 5 months of age. DDR2 were expressed in adult wild‐type male mice in Leydig cells. The number of differentiated spermatozoa in the seminal fluid was significantly lower in the Ddr2slie/slie mutant mice than in the wild‐type mice. The number of TUNEL‐positive cells was significantly greater in 5‐month‐old Ddr2slie/slie mutants. Testosterone was significantly reduced at 5 months of age, but LH was similar in both types of mice at both 10 weeks and 5 months of age. The expression levels of LH receptors (Lhcgr), StAR, P450scc, and Hsd3β6 were not significantly different between the two types of mice at 10 weeks of age, but they were significantly reduced in 5‐month‐old Ddr2slie/slie mutants compared to wild‐type mice of the same age. DDR2 was expressed in the Leydig cells of adult wild‐type male mice. In conclusion, our results indicated that DDR2 signaling plays a critical role in the maintenance of male spermatogenesis. Mol. Reprod. Dev. 77: 29–37, 2010. © 2009 Wiley‐Liss, Inc.
The role of children's routines of daily living, supervision, and maternal fatigue in preschool children's injury risk
Authors: Koulouglioti Christina , Cole Robert , Kitzman Harriet 
Published: August 2009

AbstractThe purpose of this study was to (a) explore the relationship between the lack of everyday routines and children's unintentional injuries, (b) examine two mechanisms of effect through which lack of routines might operate, children's sleep and maternal supervision, and (c) explore the influence of maternal fatigue in routines and maternal supervision. The sample comprised 264 mothers and their 3‐year‐old children. Routines were not directly related to children's injuries, but they moderated the relationship between maternal supervision and injuries. Lack of supervision was positively related to injuries only for children with infrequent everyday routines. Infrequent everyday routines were also related to inadequate children's sleep and maternal fatigue was inversely related to routines and maternal supervision. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:517–529, 2009
A novel peak detection approach with chemical noise removal using short‐time FFT for prOTOF MS data
Authors: Zhang Shuqin , DeGraba Thomas J. , Wang Honghui , Hoehn Gerard T. , Gonzales Denise A. , Suffredini Anthony F. , Ching Wai‐Ki , Ng Michael K. , Zhou Xiaobo , Wong Stephen T. C. 
Published: August 2009

AbstractPeak detection is a pivotal first step in biomarker discovery from MS data and can significantly influence the results of downstream data analysis steps. We developed a novel automatic peak detection method for prOTOF MS data, which does not require a priori knowledge of protein masses. Random noise is removed by an undecimated wavelet transform and chemical noise is attenuated by an adaptive short‐time discrete Fourier transform. Isotopic peaks corresponding to a single protein are combined by extracting an envelope over them. Depending on the S/N, the desired peaks in each individual spectrum are detected and those with the highest intensity among their peak clusters are recorded. The common peaks among all the spectra are identified by choosing an appropriate cut‐off threshold in the complete linkage hierarchical clustering. To remove the 1 Da shifting of the peaks, the peak corresponding to the same protein is determined as the detected peak with the largest number among its neighborhood. We validated this method using a data set of serial peptide and protein calibration standards. Compared with MoverZ program, our new method detects more peaks and significantly enhances S/N of the peak after the chemical noise removal. We then successfully applied this method to a data set from prOTOF MS spectra of albumin and albumin‐bound proteins from serum samples of 59 patients with carotid artery disease compared to vascular disease‐free patients to detect peaks with S/N≥2. Our method is easily implemented and is highly effective to define peaks that will be used for disease classification or to highlight potential biomarkers.
Influence of the secondary functionality on the radical‐vinyl chemistry of highly reactive monoacrylates
Authors: Kilambi Harini , Reddy Sirish K. , Schneidewind Lauren , Stansbury Jeffrey W. , Bowman Christopher N. 
Published: August 2009

AbstractThe impact of secondary functionalities on the radical‐vinyl chemistry of monoacrylates characterized by secondary functionalities that dramatically enhance their polymerization rate was elucidated utilizing experimental and computational techniques. Firstly, bulk interactions affecting the acrylate reactivity towards photopolymerization were removed by polymerizing at 5 wt % monomer in 1,4‐dioxane. Following deconvolution of bulk interactions impacting reactivity towards photopolymerization, a linear correlation between average polymerization rates and Michael addition reaction rate constants was observed on a logarithmic scale. This result indicates that the presence of the secondary functionality intramolecularly alters the monomer chemistry in a manner which impacts both of these distinct reaction types in a similar manner. These monomers exhibited reduced activation energies in both Michael addition and photopolymerization reactions as compared to hexyl acrylate. Reduction up to 20 ± 8 kJ mole−1was observed for Michael addition reactions and 12 ± 1 kJ mole−1 for photopolymerization reactions, thereby explaining the higher reactivity of the acrylates characterized by the secondary functionalities. Cyclic voltammetry experiments conducted to investigate the nature of the acrylic double bonds indicated that the rapidly polymerizing acrylates are more readily reduced as compared to traditional acrylates. Further, a distinct monotonic correlation of the irreversible cathodic peak potentials of the (meth)acrylates to photopolymerization and Michael addition reactivity was observed. The computationally estimated acrylic LUMO energies characterized by the secondary functionalities (−2.3 eV to −2.7 eV) were also found to be lower relative to hexyl acrylate (−2.2 eV). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4859–4870, 2009
Synthesis of highly refractive polyimides derived from 3,6‐bis(4‐aminophenylenesulfanyl)pyridazine and 4,6‐bis(4‐aminophenylenesulfanyl)pyrimidine
Authors: You Nam‐Ho , Nakamura Yasuhiro , Suzuki Yasuo , Higashihara Tomoya , Ando Shinji , Ueda Mitsuru 
Published: August 2009

AbstractA series of aromatic polyimides (PIs) containing pyridazine or pyrimidine in their main chains has been developed. All of the PIs were prepared from newly synthesized diamines, 3,6‐bis(4‐aminophenylenesulfanyl)pyridazine (APP), 4,6‐bis(4‐aminophenylenesulfanyl)pyrimidine (APPM) and aromatic dianhydrides, 4,4′‐[p‐thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA) and 4,4′‐oxydiphthalic anhydride (ODPA) via the conventional two‐step polycondensation. The PIs showed good thermal stability with 10% weight loss at temperatures above 450 °C and glass transition temperatures above 190 °C. Films with a 10‐μm thickness exhibited good optical transparency above 80% at 500 nm, high refractive indices ranging from 1.7218 to 1.7499, and low birefringence between 0.0066 and 0.0102. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4886–4984, 2009
Preparation of poly(amino‐amide) particles complexed with ZnO particles using silane coupling agents
Authors: Yoshioka Yayoi 
Published: August 2009

AbstractPoly(amino‐amide) particles were prepared by reacting 4,4′‐diphenyldicarbonyl chloride and 3,3′‐diaminobenzidine using a precipitation polymerization method with ultrasonic irradiation. The resulting particles had a narrow size distribution with an average diameter of 334 nm and showed excellent dispersion stability in water. The particles obtained were then modified with silane coupling agents (GPES) by reacting the amino groups of the poly(amino‐amide) particles with the epoxide rings of the GPES molecules in N,N‐dimethylformamide or N‐methylpyrrolidone using di‐n‐butyltin dilaurate as a catalyst. The amount of GPES covalently bonded to the poly(amino‐amide) particles was found to depend strongly on the reaction solvent and catalyst used. The resulting particles showed a narrow size distribution and the connections among the particles were not observed. On the other hand, the particles before and after modification showed different thermal properties and dispersion stability in water. The GPES‐modified aromatic polyamide particles were then complexed with ZnO particles with an average diameter of about 20 nm in aqueous acetic acid solution. It was found that the surface of the aromatic polyamide particles was covered with ZnO particles via hydrolysis reaction. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4908–4918, 2009
Novel silver‐loaded semi‐interpenetrating polymer network gel films with antibacterial activity
Authors: Thatiparti Thimma Reddy , Kano Arihiro , Maruyama Atsushi , Takahara Atsushi 
Published: August 2009

AbstractNovel semi‐interpenetrating polymer networks (SIPNs) based on segmented polyurethane‐urea and poly(N‐isopropylacrylamide‐co‐acrylic acid‐co‐butylmethacrylate) (poly(NIPAM‐co‐AA‐BMA)) were synthesized for the fabrication of silver nanoparticles (AgNPs) in the SIPN system that could be useful for wound dressing applications. The obtained SIPN films, after neutralization, showed high swelling in aqueous environments and good mechanical properties in both dry and hydrated states. Analysis of the dried SIPN films by differential scanning calorimetry and dynamic viscoelastic measurements revealed the presence of crosslinked copolymers as well as homopolymers in the SIPN system. The neutralized swollen SIPN film coordinated with the silver ions (Ag+) that were incorporated into it. AgNPs were subsequently formed by the reduction of Ag+. The formation of AgNPs was characterized by UV‐visible spectroscopy, atomic force microscopy, wide‐angle X‐ray diffraction, and thermogravimetric analysis (TGA). Bactericidal activity tests revealed a distinct zone of microbial inhibition within and around the silver‐doped SIPN films. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4950–4962, 2009
Formation of Nitrogen Functional Groups on Plasma Treated DLC
Authors: López‐Santos Carmen , Yubero Francisco , Cotrino José , Contreras Leopoldo , Barranco Angel , González‐Elipe Agustín R. 
Published: August 2009

AbstractDiamond like carbon (DLC) thin films have been exposed to different nitrogen containing plasmas. A dielectric barrier discharge (DBD) at atmospheric pressure and a microwave discharge (MW) at low pressure using N2 and mixtures Ar + NH3 have been compared. Optical Emission and X‐ray Photoelectron spectroscopies, Atomic Force Microscopy and contact angle measurements have been used for this study. A DBD with Ar + NH3 is the most efficient method for DLC functionalization. Films treated with this plasma presented the highest concentration of amine groups as determined by derivatization with 4‐chlorobenzaldehyde. All the treated samples underwent a significant aging with time. The efficiency of the different plasmas for DLC functionalization is discussed in the light of the intermediate species detected in the plasma.magnified image
Deposition and Characterization of Hard Coatings in the Material System V–Al–N by Reactive Magnetron Sputter Deposition
Authors: Kolozsvári Szilárd , Pesch Peter , Ziebert Carlos , Stueber Michael , Ulrich Sven 
Published: August 2009

AbstractBinary and ternary hard coatings in the system V–Al–N were deposited with varying substrate bias at substrate temperatures around 350 °C by reactive d.c. and r.f. magnetron sputtering in an Ar/N2 gas mixture from a V and/or Al target. For each experiment, Si (100) and polished 1.2379 steel substrates were placed on the rotating substrate table. VN coatings were deposited at a constant Ar flow of 250 sccm, while the bias voltage was varied between −80 and −200 V. The influence of this variation on the mechanical properties hardness and reduced elastic modulus was examined by microindentation and the critical load of failure by scratch test, friction coefficient was determined by ball‐on‐disc tribometer tests. For the deposition of AlN and VAlN coatings bias voltage, Ar/N ratio and the total pressure were varied. The chemical composition of the obtained coatings was determined by electron microprobe analysis and the crystal structure of the films was characterized by X‐ray diffraction.
Effect of Substrate Temperature and RF Biasing on the Optical Properties of Titania‐Like Thin Films Obtained by Plasma Enhanced Chemical Vapor Deposition
Authors: Sonnenfeld Axel , Rudolf von Rohr Philipp 
Published: August 2009

AbstractA low pressure radio frequency (RF) discharge (200 W) was operated in argon/oxygen with small admixtures of titanium(IV)isopropoxide (TTIP). By regulating the cooling temperature of the RF driven electrode, the influence of the substrate temperature and of the ion bombardment caused by the negative DC self‐bias of the RF electrode was investigated comparatively. Thin titania‐like films were obtained and characterized with respect to their cut‐off wavelength and their spectral absorption coefficient in the UV range. Accordingly, the cut‐off wavelength was found to be higher for films obtained on the DC‐self‐biased electrode. Here, its value appears independent of the substrate temperature and attained successively its maximum at 340 nm with deposition time. Furthermore, the absorption coefficients of films deposited on the DC self‐biased electrode are well superior to those obtained on the grounded substrate holder.
Polymer Surface Modification by Aerosol Based DBD Treatment of Foils
Authors: Mix Renate , Friedrich Joerg , Rau Alexander 
Published: August 2009

AbstractThe effect of different nebulized liquids directly introduced into the dielectric barrier discharge (DBD) was compared with simple air DBD treatment of polyethylene foils. Water, alcohols and aqueous solutions of different organic substances (environmentally compatible) and water soluble polymers were applied as aerosols and injected into the DBD zone. The DBD residence time (number of treatment cycles) and the power were varied. The durability of the surface modification effect was studied after removing of Low‐Molecular Weight Oxidized Material (LMWOM) by washing the samples with water and ethanol. The modified foils were characterized by XPS and contact angle measurements as a function of the applied plasma conditions. The concentration of functional groups at modified surfaces was estimated by derivatization and subsequent XPS measurement.magnified image