bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nicotine‐induced phosphorylation of Akt through epidermal growth factor receptor and Src in PC12h cells
Authors: Nakayama Hitoshi , Numakawa Tadahiro , Ikeuchi Toshihiko 
Published: March 2003

AbstractNicotine treatment triggers calcium influx into neuronal cells, which promotes cell survival in a number of neuronal cells. Phosphoinositide (PI) 3‐kinase and downstream PI3‐kinase target Akt have been reported to be important in the calcium‐mediated promotion of survival in a wide variety of cells. We investigated the mechanisms of nicotine‐induced phosphorylation of Akt in PC12h cells, in comparison with nicotine‐induced ERK phosphorylation. Nicotine induced Akt phosphorylation in a dose‐dependent manner. A nicotinic acetylcholine receptor (nAChR) α7 subunit‐selective inhibitor had no significant effect on nicotine‐induced Akt phosphorylation, while a non‐selective nAChR antagonist inhibited the phosphorylation. L‐type voltage‐sensitive calcium channel (VSCC) antagonists, calmodulin antagonist, and Ca2+/calmudulin‐dependent protein kinase (CaM kinase) inhibitor prevented the nicotine‐induced Akt phosphorylation. Three epidermal growth factor receptor (EGFR) inhibitors prevented the nicotine‐induced phosphorylation of both extracellular signal‐regulated protein kinase (p42/44 MAP kinase, ERK) and Akt. In contrast, an inhibitor of the Src family tyrosine kinase prevented the nicotine‐induced Akt phosphorylation but not ERK phosphorylation. These results suggested that nicotine induces the activation of both PI3‐kinase/Akt and ERK pathways via common pathways including non‐α7‐nAChRs, L‐type VSCC, CaM kinase II and EGFR in PC12h cells, but Src family tyrosine kinases only participate in the pathway to activate Akt.
Characterization and regulation of the 3β‐hydroxysteroid dehydrogenase isomerase enzyme in the rat sciatic nerve
Authors: Coirini H. , Gouézou M. , Delespierre B. , Liere P. , Pianos A. , Eychenne B. , Schumacher M. , Guennoun R. 
Published: March 2003

AbstractIn the peripheral nervous system, progesterone (PROG) has a stimulatory effect on myelination. It could be derived from local synthesis, as Schwann cells in culture express the 3β‐hydroxysteroid dehydrogenase (3β‐HSD) and convert pregnenolone (PREG) to PROG. Although 3β‐HSD mRNA can be detected by RT‐PCR in peripheral nerves, the activity of the enzyme has so far not been demonstrated and characterized in nerve tissue. In this study, we show that homogenates prepared from rat sciatic nerves contain a functional 3β‐HSD enzyme and we have analysed its kinetic properties and its regulation by steroids. The activity of 3β‐HSD in homogenates was evaluated using 3H‐labelled PREG as a substrate and NAD+ as a cofactor, the levels of steroids formed were calculated either by extrapolating the relationship between tritiated peaks obtained by TLC to the initial amount of PREG, or by gas chromatography/mass spectrometry determination. A rapid increase in PROG formation was found between 0 and 50 min of incubation and no further significant changes were observed between 1 and 4 h. The calculated Km value (1.06 ± 0.19 μm) was close to the values described for the3β‐HSD type‐I and type‐IV isoforms. Trilostane, a competitive inhibitor of the 3β‐HSD caused a potent inhibition of the rate of conversion of PREG to PROG (IC50 = 4.06 ± 2.58 μm). When the effects of different steroids were tested, both oestradiol and PROG significantly inhibited the conversion of PREG to PROG.
Vitamin E blocks early events induced by 1‐methyl‐4‐phenylpyridinium (MPP+) in cerebellar granule cells
Authors: González‐Polo Rosa A. , Soler Germán , Alvarez Alberto , Fabregat Isabel , Fuentes José M. 
Published: March 2003

AbstractExposure of cerebellar granule cells (CGCs) to 1‐methyl‐4‐phenylpyridinium (MPP+) results in apoptotic cell death, which is markedly attenuated by co‐treatment of CGCs with the radical scavenger vitamin E. Analysis of free radical production and mitochondrial transmembrane potential (ΔΨm), using specific fluorescent probes, showed that MPP+ mediates early radical oxygen species (ROS) production without a loss of ΔΨm. Exposure to MPP+ also produces an early increase in Bad dephosphorylation and translocation of Bax to the mitochondria. These events are accompanied by cytochrome c release from mitochondria to cytosol, which is followed by caspase 3 activation. Exposure of the neurons to vitamin E maintains Bad phosphorylation and attenuates Bax translocation, inhibiting cytochrome c release and caspase activation. MPP+‐mediated cytochrome c release is also prevented by allopurinol, suggesting the participation of xanthine oxidase in the process. Our results indicate that free radicals play an active role in the MPP+‐induced early events that culminate with cell death.
Two pathways for tBID‐induced cytochrome c release from rat brain mitochondria: BAK‐ versus BAX‐dependence
Authors: Brustovetsky Nickolay , Dubinsky Janet M. , Antonsson Bruno , Jemmerson Ronald 
Published: March 2003

AbstractThe mechanisms of truncated BID (tBID)‐induced Cyt c release from non‐synaptosomal brain mitochondria were examined. Addition of tBID to mitochondria induced partial Cyt c release which was inhibited by anti‐BAK antibodies, implicating BAK. Immunoblotting showed the presence of BAK, but not BAX, in brain mitochondria. tBID did not release Cyt c from rat liver mitochondria, which lacked both BAX and BAK. This indicated that tBID did not act independently of BAX and BAK. tBID plus monomeric BAX produced twice as much Cyt c release as did tBID or oligomeric BAX alone. Neither tBID alone nor in combination with BAX induced mitochondrial swelling. In both cases Cyt c release was insensitive to cyclosporin A plus ADP, inhibitors of the mitochondrial permeability transition (mPT). Recombinant Bcl‐xL inhibited Cyt c release induced by tBID alone or in combination with monomeric BAX. Koenig's polyanion, an inhibitor of VDAC, suppressed tBID‐induced Cyt c release from brain mitochondria mediated by BAK but not by BAX. Thus, tBID can induce mPT‐independent Cyt c release from brain mitochondria by interacting with exogenous BAX and/or with endogenous BAK that may involve VDAC. In contrast, neither adenylate kinase nor Smac/DIABLO was released from isolated rat brain mitochondria via BAK or BAX.
Polyamine transport, accumulation, and release in brain
Authors: Masuko Takashi , Kusama‐Eguchi Kuniko , Sakata Kaori , Kusama Tadashi , Chaki Shigeyuki , Okuyama Shigeru , Williams Keith , Kashiwagi Keiko , Igarashi Kazuei 
Published: March 2003

AbstractCycling of polyamines (spermine and spermidine) in the brain was examined by measuring polyamine transport in synaptic vesicles, synaptosomes and glial cells, and the release of spermine from hippocampal slices. It was found that membrane potential‐dependent polyamine transport systems exist in synaptosomes and glial cells, and a proton gradient‐dependent polyamine transport system exists in synaptic vesicles. The glial cell transporter had high affinities for both spermine and spermidine, whereas the transporters in synaptosomes and synaptic vesicles had a much higher affinity for spermine than for spermidine. Polyamine transport by synaptosomes was inhibited by putrescine, agmatine, histidine, and histamine. Transport by glial cells was also inhibited by these four compounds and additionally by norepinephrine. On the other hand, polyamine transport by synaptic vesicles was inhibited only by putrescine and histamine. These results suggest that the polyamine transporters present in glial cells, neurons, and synaptic vesicles each have different properties and are, presumably, different molecular entities. Spermine was found to be accumulated in synaptic vesicles and was released from rat hippocampal slices by depolarization using a high concentration of KCl. Polyamines, in particular spermine, may function as neuromodulators in the brain.
Pharmacological and immunohistochemical characterization of the APJ receptor and its endogenous ligand apelin
Authors: Medhurst Andrew D. , Jennings Carol A. , Robbins Melanie J. , Davis Robert P. , Ellis Catherine , Winborn Kim Y. , Lawrie Kenneth W. M. , Hervieu Guillaume , Riley Graham , Bolaky Jane E. , Herrity Nicole C. , Murdock Paul , Darker John G. 
Published: March 2003

AbstractApelin peptides have recently been identified to be the endogenous ligands for the G protein‐coupled receptor APJ. However, little is known about the physiological roles of this ligand‐receptor pairing. In the present study we investigated the pharmacology of several apelin analogues at the human recombinant APJ receptor using radioligand binding and functional assays. This has led to the identification of key residues in the apelin peptide required for functional potency and binding affinity through structure–activity studies. In particular, we have identified that replacement of leucine in position 5, or arginine in position 2 and 4 of the C‐terminal apelin peptide, apelin‐13, resulted in significant changes in pharmacology. We also investigated the detailed localization of pre‐proapelin and APJ receptor mRNA in a wide range of human, rat and mouse tissues using quantitative RT–PCR, and carried out a detailed immunohistochemical study of the distribution of the APJ receptor in rat brain and spinal cord. Interestingly, the APJ receptor was not only co‐localized in white matter with GFAP in the spinal cord, but was also clearly localized on neurones in the brain, suggesting that this receptor and its peptide may be involved in a wide range of biological process yet to be determined.
Methyl‐β‐cyclodextrin but not retinoic acid reduces EAAT3‐mediated glutamate uptake and increases GTRAP3‐18 expression
Authors: Butchbach Matthew E. R. , Guo Hong , Lin Chien‐liang Glenn 
Published: March 2003

AbstractThe Na+‐dependent glutamate transporter EAAT3 facilitates glutamate uptake into neurons as well as many other cell types. GTRAP3‐18 (JWA, Arl6ip5) is a novel protein that interacts with EAAT3 and negatively modulates EAAT3‐mediated glutamate uptake. Previous studies suggest that retinoic acid (RA) decreases Na+‐dependent glutamate uptake and increases GTRAP3‐18 protein expression. However, the RA used in those studies was complexed with methyl‐β‐cyclodextrin (MeβCD). In the present study we found that MeβCD, but not RA, significantly reduced Na+‐dependent EAAT3‐mediated [3H]glutamate uptake in human embryonic kidney 293 (HEK293) cells. MeβCD also significantly increased GTRAP3‐18 protein expression in HEK293 cells as well as in rat hypothalamic neuron cultures. Intracerebroventricular administration of MeβCD to the mouse brain resulted in a significant increase in GTRAP3‐18 immunoreactivity in the hippocampus and cerebral cortex. In conclusion, we have shown that MeβCD reduces EAAT3‐mediated glutamate uptake and induces the expression of GTRAP3‐18 protein.
Acidosis has opposite effects on neuronal survival during hypoxia and reoxygenation
Authors: Almaas Runar , Pytte Morten , Lindstad Julie K. , Wright Marianne , Saugstad Ola Didrik , Pleasure David , Rootwelt Terje 
Published: March 2003

AbstractTo study the effect of extracellular acidosis on apoptosis and necrosis during ischemia and reoxygenation, we exposed human post‐mitotic NT2‐N neurones to oxygen and glucose deprivation (OGD) followed by reoxygenation. In some experiments, pH of the cell medium was lowered to 5.9 during either OGD or reoxygenation or both. Staurosporine, used as a positive control for apoptosis, caused Poly(ADP‐ribose)‐polymerase (PARP) cleavage and nuclear fragmentation, but no PARP cleavage and little fragmentation were seen after OGD. Low molecular weight DNA fragments were found after staurosporine treatment, but not after OGD. No protective effect of caspase inhibitors was seen after 3 h of OGD and 21 h of reoxygenation, but after 45 h of reoxygenation caspase inhibition induced a modest improvement in 3‐(4,5‐dimethylthiazol‐2‐yl)2,5‐diphenyltetrazolium bromide (MTT) cleavage. While acidosis during OGD accompanied by neutral medium during reoxygenation protected the neurones (MTT: 228 ± 117% of neutral medium,p < 0.001), acidosis during reoxygenation only was detrimental (MTT: 38 ± 25%,p < 0.01). We conclude that apoptotic mechanisms play a minor role after OGD in NT2‐N neurones. The effect of acidosis on neuronal survival depends on the timing of acidosis, as acidosis was protective during OGD and detrimental during reoxygenation.
Interleukin‐1β stimulates macrophage inflammatory protein‐1α and ‐1β expression in human neuronal cells (NT2‐N)
Authors: Guo Chang‐Jiang , Douglas Steven D. , Lai Jian‐Ping , Pleasure David E. , Li Yuan , Williams Marge , Bannerman Peter , Song Li , Ho Wen‐Zhe 
Published: March 2003

AbstractChemokines are important mediators in immune responses and inflammatory processes of neuroimmunologic and infectious diseases. Although chemokines are expressed predominantly by cells of the immune system, neurons also express chemokines and chemokine receptors. We report herein that human neuronal cells (NT2‐N) produce macrophage inflammatory protein‐1α and ‐1β (MIP‐1α and MIP‐1β), which could be enhanced by interleukin (IL)‐1β at both mRNA and protein levels. The addition of supernatants from human peripheral blood monocyte‐derived macrophage (MDM) cultures induced MIP‐1β mRNA expression in NT2‐N cells. Anti‐IL‐1β antibody removed most, but not all, of the MDM culture supernatant‐induced MIP‐1β mRNA expression in NT2‐N cells, suggesting that IL‐1β in the MDM culture supernatants is a major factor in the induction of MIP‐1β expression. Investigation of the mechanism(s) responsible for IL‐1β‐induced MIP‐1α and ‐1β expression demonstrated that IL‐1β activated nuclear factor kappa B (NF‐κB) promoter‐directed luciferase activity in NT2‐N cells. Caffeic acid phenethyl ester, a potent and specific inhibitor of activation of NF‐κB, not only blocked IL‐1β‐induced activation of the NF‐κB promoter but also decreased IL‐1β‐induced MIP‐1α and ‐1β expression in NT2‐N cells. These data suggest that NF‐κB is at least partially involved in the IL‐1β‐mediated action on MIP‐1α and ‐1β in NT2‐N cells. IL‐1β‐mediated up‐regulation of β‐chemokine expression may have important implications in the immunopathogenesis of inflammatory diseases in the CNS.
Medicate, restrain or seclude? Strategies for dealing with violent and threatening behaviour in a Norwegian university psychiatric hospital
Authors: Wynn Rolf 
Published: March 2003

Medicate, restrain or seclude? Strategies for dealing with violent and threatening behaviour in a Norwegian university psychiatric hospital The aim of this study was to examine staff strategies for applying emergency procedures with patients who were violent or threatening. The study addressed those situations where verbal intervention, voluntary medication, and other interventions had been tried unsuccessfully and where staff found it necessary to apply emergency procedures in the shape of forced emergency medication (pharmacological restraint), physical restraint, and seclusion. The study was conducted in a 100‐bed Norwegian university psychiatric hospital. By retrospectively examining hospital records we found there were 797 episodes of physical restraint, 384 episodes of pharmacological restraint, and 88 episodes of seclusion during a five and a half year period. The preferred emergency procedures varied significantly with patients' sex, age, and diagnoses. Physical restraint was preferred more often with male, younger, and nonpsychotic patients. Pharmacological restraint was preferred more often with female patients and older patients with a nonorganic psychotic disorder. Seclusion was preferred more often with older male patients with an organic psychotic disorder.
Intersimple sequence repeat (ISSR) polymorphisms as a genetic marker system in cotton
Authors: Liu Bao , Wendel Jonathan F. 
Published: March 2003

AbstractWe studied the applicability of intersimple sequence repeat (ISSR) polymorphism in cotton. We found that: (i) the resolving power of agarose gels is poor relative to that provided by sequencing gels; (ii) fluorescent labelling of ISSR amplification primers produced numerous scorable bands; (iii) primer mixing (double priming) generated more bands than the sum of fragments resulting from two single primers, although an unexplained disappearance of several larger fragments also reproducibly occurred; (iv) ISSR fingerprinting patterns are highly heritable; and (v) double priming ISSR is an easy and informative genetic marker system in cotton for revealing both inter‐ and intraspecific variations.
Isolation and characterization of polymorphic microsatellite markers in the blowflies Lucilia illustris and Lucilia sericata
Authors: Florin A.‐B. , Gyllenstrand N. 
Published: March 2003

AbstractThirteen polymorphic microsatellite loci were developed for blowflies for use in studies of genetic differentiation in wild populations of Lucilia illustris, to detect the possible occurrence of bottlenecks and to study changes in genetic variation in laboratory populations of Lucilia sericata following artificial bottlenecks. In this preliminary study it was revealed that heterozygosity was lower than expected in wild populations and genetic variation had been lost in the laboratory population despite being kept at a large size.
St Lucia Whiptail Lizard Cnemidophorus vanzoi (Sauria: Teiidae) microsatellite primers
Authors: Rowe Graham , Dickinson Hannah C. , Gibson Richard , Funk Stephan M. , Fa John E. 
Published: March 2003

AbstractEight polymorphic microsatellite loci have been characterized for the endangered St Lucia Whiptail Lizard Cnemidophorus vanzoi. Endemic to two small islets, Maria Major and Maria Minor, off the coast of St Lucia, Lesser Antilles, the world population is estimated at < 1000 individuals. However, representatives of the systematically complex genus Cnemidophorus, containing sexual species and parthenogenetic allopolyploids, are distributed widely in North, Central and South America, and on several islands in the Caribbean Sea. These microsatellite markers are being used to monitor the genetic structure of a population of St Lucia Whiptails, recently founded through translocation, on the nearby Praslin Island.
Estimation of gene frequency and heterozygosity from pooled samples
Authors: Ritland K. 
Published: March 2003

AbstractPooling of DNA samples can significantly reduce the effort of population studies with DNA markers. I present a statistical model and numerical method for estimating gene frequency when pooled DNA is assayed for the presence/absence of alleles. Analytical and Monte‐Carlo methods examined estimation variance and bias, and hence optimal pool size, under a triangular allele frequency distribution. For gene frequency of rarer alleles, the optimal number of pooled individuals is approximately the inverse of the gene frequency. For heterozygosity, the optimal pool is approximately half the allele number; this results in pools containing, on average, 60% of possible alleles.
Isolation and characterization of microsatellite loci in wild and domestic turkeys (Meleagris gallopavo)
Authors: Latch Emily K. , Smith Edward J. , Rhodes Olin E. 
Published: March 2003

AbstractWe describe the isolation, development and application of seven microsatellite loci in the eastern wild turkey, Meleagris gallopavo silvestris, as well as their amplification and levels of polymorphism in the domestic turkey. The number of alleles per locus ranged from 5 to 15 and average heterozygosity was high for almost all loci. Domestic turkeys showed significantly reduced numbers of alleles per locus and overall heterozygosities when compared to eastern wild turkeys. The high variability in these markers should provide the level of resolution required to continue studies of wild turkey population genetics.
Characterization of 14 microsatellite marker loci in the grey bamboo lemur (Hapalemur griseus)
Authors: Sommer J. A. , Barber R. C. , Huebinger R. M. , Grassi C. , Williamson J. E. , Louis E. E. 
Published: March 2003

AbstractFourteen nuclear microsatellite loci were isolated from a genomic DNA library derived from a free‐ranging bamboo lemur (Hapalemur griseus griseus) from Ranomafana National Park, Madagascar. Expected and observed heterozygosity levels were determined for populations of bamboo lemurs from Ranomafana National Park and a nonprotected area near Tsinjoarivo, Madagascar. Although genotype frequencies for all but one marker were within Hardy–Weinberg expectations for the Tsinjoarivo population, this was not the case for the Ranomafana samples. It is probable that the deviation of genotype frequencies from Hardy–Weinberg expectations in Ranomafana was precipitated by the presence of two taxa within the sample population.
Isolation and characterization of highly polymorphic microsatellite loci in the 2‐Spot Ladybird, Adalia bipunctata
Authors: Haddrill P. R. , Majerus M. E. N. , Mayes S. 
Published: March 2003

AbstractContrary to theoretical predictions, female 2‐spot ladybirds (Adalia bipunctata) mate many more times than necessary to maintain high fertilisation success and may gain through the acquisition of material or genetic benefits. In order to investigate this mating system in detail, microsatellite markers have been isolated using a modified enrichment technique. Thirty‐nine loci were successfully amplified by polymerase chain reaction (PCR), of which only two were monomorphic. Detailed characterization of ten loci revealed very high levels of polymorphism. These markers are likely to be invaluable tools with which to study population genetics and patterns of paternity in this species.
Novel microsatellite markers for Atlantic sturgeon (Acipenser oxyrinchus) population delineation and broodstock management
Authors: Henderson‐Arzapalo A. , King T. L. 
Published: March 2003

AbstractTwenty‐one new disomic, polymorphic microsatellite DNA markers were isolated in Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus. These markers yielded a total of 220 alleles in a survey of 16 fish; two to 21 alleles/locus were observed. Each locus segregated in a Mendelian fashion when tested in a family, and a set of 14 of the loci distinguished between siblings and half‐siblings. Average observed heterozygosity ranged from 18.8 to 100.0%, and no linkage disequilibrium was detected. These loci should detect sufficient genetic diversity to allow kinship analysis for broodstock management, gene marking for stocking assessment and life history studies, and delineation of fine‐scale population structure.
A set of 35 consensus primer pairs amplifying genes and introns of plant mitochondrial DNA
Authors: Duminil J. , Pemonge M.‐H. , Petit R. J. 
Published: March 2003

AbstractBeing generally uniparentally inherited, the plant mitochondrial genome is a source of original markers potentially useful for studies of phylogeny and population genetics. We designed 24 new pairs of plant mitochondrial DNA primers that allow amplification of either introns, intergenic regions or genes. They have been defined for consensus over angiosperms and were tested along with 11 previously described mitochondrial primer pairs on 28 plant species representing 19 families of higher plants. The total set allows amplification of 40 kb (∼11%) of the mtDNA genome of Arabidopsis thaliana. The amplification rate ranged between 76% and 100% depending on the species.
Species‐specific TaqMan probes for simultaneous identification of (Gadus morhua L.), haddock (Melanogrammus aeglefinus L.) and whiting (Merlangius merlangus L.).
Authors: Taylor Martin I. , Fox Clive , Rico Ines , Rico Ciro 
Published: March 2003

AbstractWe report the development of a multiplex, single tube (TaqMan) PCR assay for the identification of three commercially important gadoid species, the cod (Gadus morhua L.), the haddock (Melanogrammus aeglefinus L.) and the whiting (Merlangius merlangus L.). The assay unambiguously identifies known adult tissue samples, and ethanol‐preserved eggs from all three species with greater than 98% accuracy, providing a powerful tool for the development of catch independent stock assessment methods, mapping of spawning sites and the detection of commercial fraud in the fishing and food production industries.