bluuebunny/crossref_metadata_2025_split huggingface dataset:
Large scale in vitro experiment system for 2 GHz exposure
Authors: Iyama Takahiro , Ebara Hidetoshi , Tarusawa Yoshiaki , Uebayashi Shinji , Sekijima Masaru , Nojima Toshio , Miyakoshi Junji 
Published: November 2004

AbstractA beam formed radiofrequency (RF) exposure‐incubator employing a horn antenna, a dielectric lens, and a culture case in an anechoic chamber is developed for large scale in vitro studies. The combination of an open type RF exposure source and a culture case through which RF is transmitted realizes a uniform electric field (±1.5 dB) in a 300 × 300 mm area that accommodates 49 35 mm diameter culture dishes. This large culture dish area enables simultaneous RF exposure of a large number of cells or various cell lines. The RF exposure source operates at 2142.5 MHz corresponding to the middle frequency of the downlink band of the International Mobile Telecommunication 2000 (IMT‐2000) cellular system. The dielectric lens, which has a gain of 7 dB, focuses RF energy in the direction of the culture case and provides a uniform electric field. The culture case is sealed and connected to the main unit for environmental control, located outside the anechoic chamber, via ducts. The temperature at the center of the tray, which contains the culture dishes in the culture room, is maintained at 37.0 ± 0.2 °C by air circulation. In addition, the appropriate CO2 density and humidity supplied to the culture case realizes stable long term culture conditions. Specific absorption rate (SAR) dosimetry is performed using an electric field measurement technique and the Finite Difference Time Domain (FDTD) calculation method. The results indicate that the mean SAR of the culture fluid at the bottom of the 49 (7 × 7 array) culture dishes used in the in vitro experiments is 0.175 W/kg for an antenna input power of 1 W and the standard deviation of the SAR distribution is 59%. When only 25 culture dishes (5 × 5 array) are evaluated, the mean SAR is 0.139 W/kg for the same antenna input power and the standard deviation of the SAR distribution is 47%. The proliferation of the H4 cell line in 72 h in a pair of RF exposure‐incubators reveals that the culture conditions are equivalent to those of a common CO2 incubator. Bioelectromagnetics 25:599–606, 2004. © 2004 Wiley‐Liss, Inc.
Evaluation of genotoxic effect of low level 50 Hz magnetic fields on human blood cells using different cytogenetic assays
Authors: Testa A. , Cordelli E. , Stronati L. , Marino C. , Lovisolo G.A. , Fresegna A.M. , Conti D. , Villani Paola 
Published: November 2004

AbstractThe question whether extremely low frequency magnetic fields (ELFMFs) may contribute to mutagenesis or carcinogenesis is of current interest. In order to evaluate the possible genotoxic effects of ELFMFs, human blood cells from four donors were exposed in vitro for 48 h to 50 Hz, 1 mT uniform magnetic field generated by a Helmholtz coil system. Comet assay (SCGE), sister chromatid exchanges (SCE), chromosome aberrations (CAs), and micronucleus (MN) test were used to assess the DNA damage. ELF pretreated cells were also irradiated with 1 Gy of X‐ray to investigate the possible combined effect of ELFMFs and ionizing radiation. Furthermore, nuclear division index (NDI) and proliferation index (PRI) were evaluated. Results do not evidence any DNA damage induced by ELFMF exposure or any effect on cell proliferation. Data obtained from the combined exposure to ELFMFs and ionizing radiation do not suggest any synergistic or antagonistic effect. Bioelectromagnetics 25:613–619, 2004. © 2004 Wiley‐Liss, Inc.
Electroporation of a lipid bilayer as a chemical reaction
Authors: Bier Martin , Gowrishankar T.R. , Chen Wei , Lee Raphael C. 
Published: November 2004

AbstractWhen a cell's transmembrane potential is increased from a physiological one to more than 370 mV, the transmembrane current increases more than hundredfold within a millisecond. This is due to the formation of conductive pores in the membrane. We construct a model in which we conceive of pore formation as a voltage sensitive chemical reaction. The model predicts the logarithm of the pore formation rate to increase proportionally to the square of the voltage. We measure currents through frog muscle cell membranes under 8 ms pulses of up to 440 mV. The experimental data appear consistent with the model. Bioelectromagnetics 25:634–637, 2004. © 2004 Wiley‐Liss, Inc.
Increased rate of chondrocyte aggregation in a wavy‐walled bioreactor
Authors: Bueno Ericka M. , Bilgen Bahar , Carrier Rebecca L. , Barabino Gilda A. 
Published: November 2004

AbstractA novel wavy‐walled bioreactor designed to enhance mixing at controlled shear stress levels was used to culture chondrocytes in suspension. Chondrocyte aggregation in suspensions mixed at 30, 50, and 80 rpm was characterized in the wavy‐walled bioreactor and compared with that in conventional smooth‐walled and baffled‐walled spinner flask bioreactors. Aggregation was characterized in terms of the percentage of cells that aggregated over time, and aggregate size changes over time. The kinetics of chondrocyte aggregation observed in the bioreactors was composed of two phases: early aggregation between 0 and 2 h of culture, and late aggregation between 3 and 24 h of culture. At 50 rpm, the kinetics of early aggregation in the wavy‐walled bioreactor was approximately 25% and 65% faster, respectively, than those in the smooth‐walled and baffled‐walled spinner flask bioreactors. During the late aggregation phase, the kinetics of aggregation in the wavy‐walled bioreactor were approximately 45% and 65% faster, respectively, than in the smooth‐walled and baffled‐walled spinner flasks. The observed improved kinetics of chondrocyte aggregation was obtained at no cost to the cell survival rate. Results of computerized image analysis suggest that chondrocyte aggregation occurred initially by the formation of new aggregates via cell–cell interactions and later by the joining of small aggregates into larger cell clumps. Aggregates appeared to grow for only a couple of hours in culture before reaching a steady size, possibly determined by limitations imposed by the hydrodynamic environment. These results suggest that the novel geometry of the wavy‐walled bioreactor generates a hydrodynamic environment distinct from those traditionally used to culture engineered cartilage. Such differences may be useful in studies aimed at distinguishing the effects of the hydrodynamic environment on tissue‐engineered cartilage. Characterizing the wavy‐walled bioreactor's hydrodynamic environment and its effects on cartilage cell/tissue culture can help establish direct relationships between hydrodynamic forces and engineered tissue properties. © 2004 Wiley Periodicals, Inc.
Kinetic analysis of RSK2 and Elk‐1 interaction on the serum response element and implications for cellular engineering
Authors: Aksan Kurnaz Isil 
Published: November 2004

AbstractImmediate early gene activation upon mitogenic activation occurs through the serum response element (SRE), which makes the delineation of the upstream pathways a powerful means to engineer cellular responses. The malfunctioning of this system leads to a variety of disorders, ranging from neurological disorders such as Coffin‐Lowry syndrome (RSK2 mutations) to cancer (c‐fos mutations). We therefore investigated the SRE activation mechanism in a typical mammalian cell. Mitogenic signaling uses the mitogen‐activated protein kinase (MAPK) module through increased binding of the ternary complex factor (TCF), such as Elk‐1, to the promoter DNA (the SRE element) and subsequent transcriptional activation, as well as through activation of a histone kinase, such as the MAPK‐activated protein kinase (MAPKAP‐K) ribosomal S6 kinase (RSK2). This computational model uses the biochemical simulation environment GEPASI 3.30 to investigate three major models of interaction for Elk‐1 and RSK2, and to study the effect of histone acetyl transferase (HAT) recruitment in each of these models on the local chromatin modifications in the presence and absence of MAPK activation. We show that the quickest response on the chromatin can be achieved in the presence of a preformed complex of RSK2, Elk‐1 and HAT, with HAT being activated upon dissociation from the complex upon activation of the MAPK cascade. This study presents critical components in the pathway that can be targeted for engineering of specific inhibitors or activators of the system. © 2004 Wiley Periodicals, Inc.
Engineering Chinese hamster ovary cells to maximize effector function of produced antibodies using FUT8 siRNA
Authors: Mori Katsuhiro , Kuni‐Kamochi Reiko , Yamane‐Ohnuki Naoko , Wakitani Masako , Yamano Kazuya , Imai Harue , Kanda Yutaka , Niwa Rinpei , Iida Shigeru , Uchida Kazuhisa , Shitara Kenya , Satoh Mitsuo 
Published: November 2004

AbstractWe explored the possibility of converting established antibody‐producing cells to cells producing high antibody‐dependent cellular cytotoxicity (ADCC) antibodies. The conversion was made by constitutive expression of small interfering RNA (siRNA) against α1,6 fucosyltransferase (FUT8). We found two effective siRNAs, which reduce FUT8 mRNA expression to 20% when introduced into Chinese hamster ovary (CHO)/DG44 cells. Selection for Lens culinaris agglutinin (LCA)‐resistant clones after introduction of the FUT8 siRNA expression plasmids yields clones producing highly defucosylated (≈60%) antibody with over 100‐fold higher ADCC compared to antibody produced by the parental cells (≈10% defucosylated). Moreover, the selected clones remain stable, producing defucosylated antibody even in serum‐free fed‐batch culture. Our results demonstrate that constitutive FUT8 siRNA expression can control the oligosaccharide structure of recombinant antibody produced by CHO cells to yield antibodies with dramatically enhanced ADCC. © 2004 Wiley Periodicals, Inc.
Neurotransmitter properties of spinal interneurons in embryonic and larval zebrafish
Authors: Higashijima Shin‐Ichi , Schaefer Michael , Fetcho Joseph R. 
Published: November 2004

AbstractMany classes of spinal interneurons in zebrafish have been described based on morphology, but their transmitter phenotypes are largely unknown. Here we combine back‐filling or genetic labeling of spinal interneurons with in situ staining for markers of neurotransmitter phenotypes, including the vesicular glutamate transporter (VGLUT) genes for glutamatergic neurons, the neuronal glycine transporter (GLYT2) for glycinergic neurons, and glutamic acid decarboxylase (GAD) for GABAergic neurons. Neurons positive for VGLUT include the commissural CoPA, MCoD, UCoD, and some of the CoSA neurons. The CiD interneurons, which have ipsilateral descending axons, were also VGLUT‐positive, as were the ventrally located VeMe interneurons, whose descending axonal trajectory has not been clearly revealed. Cells positive for GLYT2 include the commissural CoLAs as well as some of the CoBL and CoSA neurons. The CiA cells were the only GLYT2‐positive cells with an ipsilateral axon. Cells staining for GAD included, most notably, the dorsal longitudinal ascending (DoLA) and KA interneurons. Our approach allowed us to define the likely transmitter phenotypes of most of the known classes of spinal interneurons. These data provide a foundation for understanding the functional organization of the spinal networks in zebrafish. J. Comp. Neurol. 480:19–37, 2004. © 2004 Wiley‐Liss, Inc.
Ontogeny and innervation patterns of dopaminergic, noradrenergic, and serotonergic neurons in larval zebrafish
Authors: McLean David L. , Fetcho Joseph R. 
Published: November 2004

AbstractWe report the development of aminergic neurons from 0–10 days postfertilization (dpf) in zebrafish (Danio rerio). This study was prompted by the lack of information regarding patterns of spinal aminergic innervation at early stages, when the fish are accessible to optical, genetic, and electrophysiological approaches toward understanding neural circuit function. Our findings suggest that aminergic populations with descending processes are among the first to appear during development. Descending aminergic fibers, revealed by antibodies to tyrosine hydroxylase (TH) and serotonin (5‐hydroxytryptamine; 5‐HT), innervate primarily the ventral (TH, 5‐HT), but also the dorsal (5‐HT) aspects of the spinal cord by 4 dpf, with the extent of innervation not changing markedly up to 10 dpf. By tracking the spatiotemporal expression of TH, 5‐HT, and dopamine beta hydroxylase reactivity, we determined that these fibers likely originate from neurons in the posterior tuberculum (dopamine), the raphe region (5‐HT) and, possibly, the locus coeruleus (noradrenaline). In addition, spinal neurons positive for 5‐HT emerge between 1–2 dpf, with processes that appeared to descend along the ventrolateral cord for only 1–2 muscle segments. Their overall morphology distinguished these cells from previously described “VeMe” (ventromedial) interneurons, which are also located ventromedially, but have long, multisegmental descending processes. We confirmed the distinction between spinal serotonergic and VeMe interneurons using fish genetically labeled with green fluorescent protein. Our results suggest that the major aminergic systems described in adults are in place shortly after hatching, at a time when zebrafish are accessible to a battery of techniques to test neuronal function during behavior. J. Comp. Neurol. 480:38–56, 2004. © 2004 Wiley‐Liss, Inc.
Organization of rat vibrissa motor cortex and adjacent areas according to cytoarchitectonics, microstimulation, and intracellular stimulation of identified cells
Authors: Brecht Michael , Krauss Andreas , Muhammad Sajjad , Sinai‐Esfahani Laleh , Bellanca Sebastiano , Margrie Troy W. 
Published: November 2004

AbstractThe relationship between motor maps and cytoarchitectonic subdivisions in rat frontal cortex is not well understood. We use cytoarchitectonic analysis of microstimulation sites and intracellular stimulation of identified cells to develop a cell‐based partitioning scheme of rat vibrissa motor cortex and adjacent areas. The results suggest that rat primary motor cortex (M1) is composed of three cytoarchitectonic areas, the agranular medial field (AGm), the agranular lateral field (AGl), and the cingulate area 1 (Cg1), each of which represents movements of different body parts. Vibrissa motor cortex corresponds entirely and for the most part exclusively to AGm. In area AGl body/head movements can be evoked. In posterior area Cg1 periocular/eye movements and in anterior area Cg1 nose movements can be evoked. In all of these areas stimulation thresholds are very low, and together they form a complete representation of the rat's body surface. A strong myelinization and an expanded layer 5 characterize area AGm. We suggest that both the strong myelinization and the expanded layer 5 of area AGm may represent cytoarchitectonic specializations related to control of high‐speed whisking behavior. J. Comp. Neurol. 479:360–373, 2004. © 2004 Wiley‐Liss, Inc.
Effect of vanillin on toxicant‐induced mutation and mitotic recombination in proliferating somatic cells of Drosophila melanogaster
Authors: Sinigaglia Marialva , Reguly Maria Luíza , de Andrade Heloísa Helena Rodrigues 
Published: November 2004

AbstractVanillin (VA; C8H8O3) is a flavoring agent that in previous studies has both increased and decreased the genotoxicity of chemical agents, depending on the nature of both the agent and the genetic event measured. The ability of VA to modulate the mutagenicity and recombinogenicity of three different monoalkylating agents, N‐ethyl‐N‐nitrosourea (ENU), N‐methyl‐N‐nitrosourea (MNU), and ethyl methanesulfonate (EMS), and the intercalating agent bleomycin (BLEO) was examined using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. While neither the mutagenicity nor the recombinagenicity of ENU or MNU was modified by posttreatment with VA, EMS‐induced genetic toxicity was enhanced by as much as 30%. This overall enhancement included a synergistic increase in mitotic recombination and a lesser decrease in mutation. Posttreatment with VA also produced an increase in the genotoxicity of BLEO, which was characterized by increases of 120% and 180% for 0.5% and 1% VA, respectively. This enhancement was restricted to an increase in recombinational events, since no alteration in BLEO‐induced mutation was observed. The data suggest that the major VA‐modulatory action on genotoxicity in D. melanogaster is related to its synergistic effects on somatic recombination, which has a greater consequence on overall genotoxicity than its antimutagenic effects. Since the SMART assay is specifically sensitive to mitotic crossing‐over, our data suggest that VA promotes toxicant‐induced homologous recombination, at least in the proliferative cells of Drosophila. Environ. Mol. Mutagen. 2004. © 2004 Wiley‐Liss, Inc.
Improved gas chromatographic stereodifferentiation of chiral main constituents from different essential oils using a mixture of chiral stationary phases
Authors: Bayer Mathias , Mosandl Armin 
Published: November 2004

AbstractThe simultaneous enantioselective gas chromatographic differentiation of the chiral main compounds of lavender, neroli, petitgrain and bitter orange oil [limonene, linalool, linalool oxides (furanoid), linalyl acetate, (E)‐nerolidol, α‐pinene, β‐pinene, terpinen‐4‐ol and α‐terpineol] is described, using a deﬁned mixture of heptakis(2,3‐di‐O‐methyl‐6‐O‐tert‐butyldimethylsilyl)‐β‐cyclodextrin and heptakis(2,3‐di‐O‐acetyl‐6‐O‐tert‐butyldimethylsilyl)‐β‐cyclodextrin as the chiral stationary phase. Copyright © 2004 John Wiley & Sons, Ltd.
Intra‐oral detection of potent odorants using a modiﬁed stir‐bar sorptive extraction system in combination with HRGC–O, known as the buccal odour screening system (BOSS)
Authors: Buettner Andrea , Welle Frank 
Published: November 2004

AbstractThe topic of this work was to develop a novel approach that can be used to identify potent odorants intraorally and to determine their dwell time within the oral cavity. The technique, called buccal odour screening system (BOSS), is based on a modiﬁed stir bar sorptive extraction (SBSE) system. It comprises the intra‐oral extraction of odour compounds at deﬁned times after food consumption under optimized in vivo sampling conditions, together with analysis via high resolution gas chromatography–olfactometry (HRGC–O). The obtained analytical data were related to timeresolved retronasal aroma evaluation. This allowed the characterization of prolongued aroma perception elicited after oral aroma application in relation to aroma concentration changes in vivo. For validation of the system, model assays were performed on important aroma compounds in aqueous solutions to ensure sufﬁcient sensitivity of the applied SBSE system under the given extraction conditions. Copyright © 2004 John Wiley & Sons, Ltd.
Exchange transfusion with synthetic oxygen‐carrying plasma protein “albumin‐heme” into an acute anemia rat model after seventy‐percent hemodilution
Authors: Komatsu Teruyuki , Yamamoto Hisashi , Huang Yubin , Horinouchi Hirohisa , Kobayashi Koichi , Tsuchida Eishun 
Published: November 2004

AbstractRecombinant human serum albumin (rHSA) incorporating the synthetic heme “albumin‐heme” is an oxygen‐carrying plasma protein that has the potential to be a red blood cell substitute. The physiological responses to a 30% exchange transfusion with two types of albumin‐heme (rHSA‐FecycP, rHSA‐FepivP) solutions after 70% isovolemic hemodilution with 5 g/dL rHSA were investigated using anesthetized rats. The circulation parameters, blood parameters, renal cortical oxygen pressure (pO2), and muscle tissue pO2 were carefully monitored for 60 min after the injection. The declined mean arterial pressure and the mixed venous partial pO2 significantly recovered to 70.8 and 91.9% of the basal values by intravenous infusion of albumin‐hemes, respectively. The lowered renal cortical pO2 also increased, indicating oxygen transport by this synthetic hemoprotein. The administration of albumin‐heme into the acute anemia rat model after hemorrhage improved the circulatory volume and resuscitated the shock state. Both rHSA‐FecycP and rHSA‐FepivP transported oxygen through the body. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 644–651, 2004
Effects of subtoxic concentrations of benzoyl peroxide on cell lipid metabolism
Authors: Datar R. , Rueggeberg Fredrick A. , Caughman G. B. , Wataha John C. , Lewis Jill , Schuster G. S. 
Published: November 2004

AbstractBenzoyl peroxide (BP), a tumor promoter, has been shown to cause free‐radical–induced lipid peroxidation and membrane damage at toxic concentrations. However, its effects on lipid metabolism at concentrations that were not overtly toxic have not been investigated. The purpose of the current study was to examine the effects of BP and its final degradation product, benzoic acid (BA), on lipid metabolism. Two cell lines, hamster cheek pouch (HCP) and human monocytes (THP‐1), were used to determine the effects of BP, BA, and BP combined with FeCl2 on cell lipid metabolism. Cells were exposed to BP and 14C acetate for 24 h, or cells with prelabeled lipids were harvested, and the lipids were extracted and separated with the use of thin‐layer chromatography. Lipid metabolism of some neutral lipids such as triglycerides was altered for both cell types in response to BP. Also, cholesterol content was reduced in THP‐1 cells and a phospholipid, phosphatidylethanolamine (PE), was reduced in HCP cells. The final degradation product of BP, BA, failed to elicit any response in lipid metabolism. Subtoxic concentrations of BP induced changes in neutral lipids such as triglycerides and cholesterol. The metabolism of major phospholipids except PE remained unchanged. The effects were related to BP and its degradation and varied with the cell type. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 685–692, 2004
Existence of non‐resolvable Steiner triple systems
Authors: Ching Li (Ben) Pak , van Rees G. H. J. 
Published: November 2004

AbstractWe consider two well‐known constructions for Steiner triple systems. The first construction is recursive and uses an STS(v) to produce a non‐resolvable STS(2v + 1), forv ≡ 1 (mod 6). The other construction is the Wilson construction that we specify to give a non‐resolvable STS(v), forv ≡ 3 (mod 6),v > 9. © 2004 Wiley Periodicals, Inc. J Combin Designs 13: 16–24, 2005.
Kirkman packing and covering designs with spanned holes of size 2
Authors: Yin Jianxing 
Published: November 2004

AbstractA Kirkman holey packing (resp. covering) design, denoted by KHPD(gu) (resp. KHCD(gu)), is a resolvable (gu, 3, 1) packing (resp. covering) design of pairs with u disjoint holes of size g, which has the maximum (resp. minimum) possible number of parallel classes. Each parallel class contains one block of size δ, while other blocks have size 3. Here δ is equal to 2, 3, and 4 when gu ≡ 2, 3, and 4 (mod 3) in turn. In this paper, the existence problem of a KHPD(2u) and a KHCD(2u) is solved with one possible exception of a KHPD(28). © 2004 Wiley Periodicals, Inc.