bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in retinal expression of neurotrophins and neurotrophin receptors induced by ocular hypertension
Authors: Rudzinski Marcelo , Wong Tak‐Pan , Uri Saragovi H. 
Published: January 2004

AbstractOpen angle glaucoma is defined as a progressive and time‐dependent death of retinal ganglion cells concomitant with high intraocular pressure, leading to loss of visual field. Because neurotrophins are a family of growth factors that support neuronal survival, we hypothesized that quantitative and qualitative changes in neurotrophins or their receptors may take place early in ocular hypertension, preceding extensive cell death and clinical features of glaucoma. We present molecular, biochemical, and phenotypic evidence that significant neurotrophic changes occur in retina, which correlate temporally with retinal ganglion cell death. After 7 days of ocular hypertension there is a transient up‐regulation of retinal NGF, while its receptor TrkA is up‐regulated in a sustained fashion in retinal neurons. After 28 days of ocular hypertension there is sustained up‐regulation of retinal BDNF, but its receptor TrkB remains unchanged. Throughout, NT‐3 levels remain unchanged but there is an early and sustained increase of its receptor TrkC in Müller cells but not in retinal ganglion cells. These newly synthesized glial TrkC receptors are truncated, kinase‐dead isoforms. Expression of retinal p75 also increases late at day 28. Asymmetric up‐regulation of neurotrophins and neurotrophin receptors may preclude efficient neurotrophic rescue of RGCs from apoptosis. A possible rationale for therapeutic intervention with Trk receptor agonists and p75 receptor antagonists is proposed. © 2003 Wiley Periodicals, Inc. J Neurobiol 58: 341–354, 2004
Inducible transcript expressed by reactive epithelial cells at sites of olfactory sensory neuron proliferation
Authors: Stoss Thomas D. , Nickell Melissa D. , Hardin Debra , Derby Charles D. , McClintock Timothy S. 
Published: January 2004

AbstractThe continuous replacement of cells in the spiny lobster olfactory organ depends on proliferation of new cells at a specific site, the proximal proliferation zone (PPZ). Using representational difference analysis of cDNA, we identified transcripts enriched in the PPZ compared to the mature zone (MZ) of the organ. The 12 clones identified included four novel sequences, three exoskeletal proteins, a serine protease, two protease inhibitors, a putative growth factor, and a sequence named PET‐15 that has similarity to antimicrobial proteins of the crustin type. PET‐15 mRNA was only detected in epithelial cells. It was abundant in all epithelial cells of the PPZ, but was only detected in the MZ at sites of damage to the olfactory organ. PET‐15 mRNA was increased by types of damage that are known to induce proliferation of new olfactory sensory neurons in the olfactory organ. It increased in the PPZ after partial ablation of the olfactory organ and in the MZ after shaving of aesthetasc sensilla. These ipsilateral effects were mirrored by smaller increases in the undamaged contralateral olfactory organ. These contralateral effects are most parsimoniously explained by the action of a diffusible signal. Because epithelial cells are the source of proliferating progenitors in the olfactory organ, the same diffusible signal may stimulate increases in both cellular proliferation and PET‐15 mRNA. The uniformity of expression of PET‐15 in the PPZ epithelium suggests that the epithelial cells that give rise to new olfactory sensory neurons are a subset of cells that express PET‐15. © 2003 Wiley Periodicals, Inc. J Neurobiol 58: 355–368, 2004
Odor‐evoked responses in the olfactory center neurons in the terrestrial slug
Authors: Murakami Masayoshi , Watanabe Satoshi , Inoue Tsuyoshi , Kirino Yutaka 
Published: January 2004

AbstractThe procerebrum (PC) of the terrestrial mollusk Limax is a highly developed second‐order olfactory center consisting of two electrophysiologically distinct populations of neurons: nonbursting (NB) and bursting (B). NB neurons are by far the more numerous of the two cell types. They receive direct synaptic inputs from afferent fibers from the tentacle ganglion, the primary olfactory center, and also receive periodic inhibitory postsynaptic potentials (IPSPs) from B neurons. Odor‐evoked activity in the NB neurons was examined using perforated patch recordings. Stimulation of the superior tentacle with odorants resulted in inhibitory responses in 45% of NB neurons, while 11% of NB neurons showed an excitatory response. The specific response was reproducible in each neuron to the same odorant, suggesting the possibility that activity of NB neurons may encode odor identity. Analysis of the cycle‐averaged membrane potential of NB neurons revealed a correlation between the firing rate and the membrane potential at the plateau phase between IPSPs. Also, the firing rate of NB neurons was affected by the frequency of the IPSPs. These results indicate the existence of two distinct mechanisms for the regulation of NB neuron activity. © 2003 Wiley Periodicals, Inc. J Neurobiol 58: 369–378, 2004
TBX2/TBX3 transcriptional factor homologue controls olfactory adaptation in Caenorhabditis elegans
Authors: Miyahara Kohji , Suzuki Norio , Ishihara Takeshi , Tsuchiya Eiko , Katsura Isao 
Published: January 2004

AbstractAlthough transcriptional factors are known to play important roles in synaptic plasticity, their role in olfactory adaptation has not been studied well. Here we report that Ce‐TBX‐2, the TBX2/TBX3 transcriptional factor homologue of the nematode Caenorhabditis elegans, is involved in olfactory adaptation. Two missense hypomorphic mutations in this gene confer abnormality in adaptation, but not chemotaxis, to all the odorants sensed by AWC olfactory neurons. The Ce‐tbx‐2 gene is expressed in AWB, AWC, ASJ, and many pharyngeal neurons, but expression in AWC neurons is sufficient for normal adaptation. Unexpectedly, the protein product is localized mostly in cytoplasm. The AWC neurons in the mutants retain their characteristic morphology and many marker gene expressions, suggesting that the mutants are abnormal in neural functions rather than neuronal differentiation. The results of this study imply that some of the mammalian T‐box family proteins, which play central roles in embryonic development, may also control functions like neural plasticity in differentiated neurons. © 2003 Wiley Periodicals, Inc. J Neurobiol 58: 392–402, 2004
Identification of a proctolin preprohormone gene (Proct) of Drosophila melanogaster: Expression and predicted prohormone processing
Authors: Taylor Christine A. M. , Winther Åsa M. E. , Siviter Richard J. , Shirras Alan D. , Isaac R. Elwyn , Nässel Dick R. 
Published: January 2004

AbstractProctolin was the first insect neuropeptide to be sequenced and has been the subject of many physiological and pharmacological studies in insects and crustaceans. We have identified a Drosophila gene (CG7105, Proct) encoding a precursor protein containing the neuropeptide proctolin (RYLPT). In situ hybridization with a riboprobe to the Proct gene revealed a distribution of transcript in neurons of the larval central nervous system (CNS) matching that seen with antiserum to proctolin. An antiserum raised to a sequence in the precursor downstream of proctolin labeled the same neurons as those seen with the antiproctolin antisera. The predicted protein encoded by Proct has a single copy of the RYLPT sequence that directly follows the predicted signal peptidase cleavage point and precedes a consensus recognition site for a furinlike processing endoprotease. Ectopic expression of Proct in the CNS and midgut via the GAL4‐UAS system, using an Actin5C‐GAL4 driver, confirmed that the predicted preproproctolin can be processed to generate immunoreactive proctolin peptide. Pupae over‐expressing Proct displayed a 14% increase in heart rate, providing evidence in support of a cardioacceleratory endocrine function for proctolin in Drosophila. The distribution of proctolin suggests roles as a neuromodulator in motoneurons and interneurons, and as a neurohormone that could be released from brain neurosecretory cells with terminations in the ring gland. © 2003 Wiley Periodicals, Inc. J Neurobiol 58: 379–391, 2004
Regulation of dendritic length and branching by semaphorin 3A
Authors: Fenstermaker Vivian , Chen Yachi , Ghosh Anirvan , Yuste Rafael 
Published: January 2004

AbstractThe molecular mechanisms that control dendritic development are still unclear. Semaphorin 3A, a class III semaphorin, has been shown to regulate the radial orientation of pyramidal neurons in the developing neocortex. Here, we investigate the effects of Sema3A on the development of dendritic topology. Neocortical slices from Sema3A null mutant mice were cultured and neurons were transfected with GFP, reconstructed, and compared with neurons from wild‐type and heterozygote littermates. We also added exogenous Sema3A to cultured wild‐type neocortical slices to further test its effects on dendritic development. We document reductions in dendritic length and branching in Sema3A null mice and increases in dendritic length and branching after the addition of exogenous Sema3A to wild‐type neurons. We conclude that Sema3A is necessary for the elaboration of second and third order dendritic branches in pyramidal neurons. © 2003 Wiley Periodicals, Inc. J Neurobiol 58: 403–412, 2004
V Fenstermaker, Y Chen, A Ghosh, R Yuste. Regulation of dendritic length and branching by Semaphorin 3A, Journal of Neurobiology (2004) 58(3) 403–412
Authors: Fenstermaker Vivian , Chen Yachi , Ghosh Anirvan , Yuste Rafael 
Published: January 2004

AbstractThe original article to which this Erratum refers was published in Journal of Neurobiology (2004) 58(3) 403–412
Partition of unity enrichment for bimaterial interface cracks
Authors: Sukumar N. , Huang Z. Y. , Prévost J.‐H. , Suo Z. 
Published: January 2004

AbstractPartition of unity enrichment techniques are developed for bimaterial interface cracks. A discontinuous function and the two‐dimensional near‐tip asymptotic displacement functions are added to the finite element approximation using the framework of partition of unity. This enables the domain to be modelled by finite elements without explicitly meshing the crack surfaces. The crack‐tip enrichment functions are chosen as those that span the asymptotic displacement fields for an interfacial crack. The concept of partition of unity facilitates the incorporation of the oscillatory nature of the singularity within a conforming finite element approximation. The mixed‐mode (complex) stress intensity factors for bimaterial interfacial cracks are numerically evaluated using the domain form of the interaction integral. Good agreement between the numerical results and the reference solutions for benchmark interfacial crack problems is realized. Copyright © 2004 John Wiley & Sons, Ltd.
Evaporative light scattering detection of pyrrolizidine alkaloids
Authors: Schaneberg Brian T. , Molyneux Russell J. , Khan Ikhlas A. 
Published: January 2004

AbstractA reverse‐phase high‐performance liquid chromatography method utilizing evaporative light scattering detection (ELSD) has been developed for the simultaneous detection of hepatotoxic pyrrolizidine alkaloids with and without chromophores, namely, riddelliine, riddelliineN‐oxide, senecionine, senecionineN‐oxide, seneciphylline, retrorsine, integerrimine, lasiocarpine and heliotrine. Pyrrolizidine alkaloids were detected in ﬁve plant extracts (Senecio spartioides,S. douglasii var. longilobus,S. jacobaea,S. intergerrimus var. exaltatusandSymphytum ofﬁcinale). The detection of heliotrine (which does not contain a chromophore) was much improved by ELSD compared with photodiode array detection. Copyright © 2004 John Wiley & Sons, Ltd.
Quantiﬁcation of allergenic urushiols in extracts of Ginkgo biloba leaves, in simple one‐step extracts and reﬁned manufactured material (EGb 761)
Authors: Schötz Karl 
Published: January 2004

AbstractExtracts of leaves of Ginkgo biloba (family Ginkgoaceae), widely used in the treatment of peripheral and cerebral circulatory disorders as well as for dementia of different aetiology, contain long chain alkylphenols (with allergenic, cytotoxic, mutagenic and tumour‐promoting properties) together with the extremely potent allergens, the urushiols. Such hazardous compounds can be present only in very low concentrations in phyto‐pharmaceutical preparations and hence, for the purposes of drug safety, techniques must be available for the identiﬁcation and quantiﬁcation of these allergens at extremely low levels in reﬁned manufactured materials. GC‐MS analysis of samples collected at various stages during the production process of a standardised extract of G. biloba (EGb 761) demonstrated that all alkylphenols present in the primary acetone extracts were removed in parallel with the same efﬁciency irrespective of their aromatic substitution pattern. Furthermore, in the ﬁnal product the content of urushiols was generally below the detection limit of 0.03 ppm. Therefore, it is concluded that demonstrating the absence of the predominant, and easily quantiﬁable, ginkgolic acids provides a reliable means for the control of pharmaceutical quality of the ﬁnal product. Copyright © 2004 John Wiley & Sons, Ltd.
HPLC‐PAD‐APCI/MS assay of phenylpropanoids in cereals
Authors: Bily Antoine C. , Burt Andrew J. , Ramputh Al‐Idrissi , Livesey John , Regnault‐Roger Catherine , Philogène Bernard R. , Arnason John T. 
Published: January 2004

AbstractA new, rapid HPLC‐PAD‐APCI/MS assay has been developed in order to measure accurately the amount of p‐coumaric, E‐ and Z‐ferulic acid and the dehydrodimers of ferulic acid in cereal grain. In the positive ionisation mode, MS patterns gave additional information for the identiﬁcation of the dimers. The time required and the quantities of solvents employed in the developed analytical method are much lower than those involved in previously available assays of these compounds, thus making the method suitable for the screening of cereal genotypes. Application of the method to accessions of maize, wheat and sorghum showed that E‐ferulic was the most abundant phenylpropanoid, whilst the major dimer was 8‐O‐4′ dehydrodimer of ferulic acid followed by the 5–5′ and then the 8–5′ forms. Maize grains, especially of the Mexican landraces, contained the highest levels of these dimers. Copyright © 2004 John Wiley & Sons, Ltd.
Quantitative determination of Aconitum alkaloids in blood and urine samples by high‐performance liquid chromatography
Authors: Wang Zhao Hong , Guo Dean , He Yi , Hu Chunhua , Zhang Jizong 
Published: January 2004

AbstractAn HPLC method has been developed for the simultaneous determination of the toxic Aconitum alkaloids, aconitine, mesaconitine and hypaconitine in blood and urine samples. The samples were initially subjected to solid phase extraction using Oasis® MCX cartridges, and the alkaloids were separated on an XTerra™ RP18 column, gradient‐eluted with acetonitrile: ammonium hydrogen carbonate buffer. Calibration curves were linear in the range 2.75–550 ng for aconitine and hypaconitine, and 3–600 ng for mesaconitine: the limit of detection was 0.1 ng (signal‐to‐noise ratio of 3) for each alkaloid. The described analysis proved to be sensitive, rapid and economical, and will be applied in the identiﬁcation and determination of these alkaloids in forensic and therapeutic drug monitoring. Copyright © 2004 John Wiley & Sons, Ltd.
Analytical characterisation of crude extracts from an african Ancistrocladus species using high‐performance liquid chromatography and capillary electrophoresis coupled to ion trap mass spectrometry
Authors: Unger Matthias , Dreyer Michael , Specker Sven , Laug Stefanie , Pelzing Matthias , Neusüß Christian , Holzgrabe Ulrike , Bringmann Gerhard 
Published: January 2004

AbstractThe analysis by HPLC, CE and CE‐MS/MS of root bark extracts of a, so far undescribed, Central‐African Ancistrocladus species (family Ancistrocladaceae) is described. Owing to the complexity of the extract, the application of reversed‐phase HPLC resulted in a partially incomplete separation of the naphthylisoquinoline alkaloids, whilst CE using a non‐aqueous buffer proved to be a very valuable complementary method for a ﬁrst characterisation of the crude extract. By performing additional CE‐MS/MS experiments, in combination with parallel isolation studies and structural elucidation using conventional methods, six alkaloidal substances present in the plant could be identiﬁed. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of colchicine in Colchicum steveni and C. hierosolymitanum (colchicaceae): comparison between two analytical methods
Authors: Alali Feras , Tawaha Khaled , Qasaymeh Rana M. 
Published: January 2004

AbstractThe amounts of colchicine present in two Jordanian species of Colchicum, namely, C. steveni Kunth and C. hierosolymitanum Feibrun (Colchicaceae), have been determined. An HPLC‐UV (photodiode array) method employing gradient elution was developed and the results compared with those obtained using a simple TLC‐spectrophotometric method. The levels of colchicine as measured by these methods were not signiﬁcantly different (p < 0.05) indicating that the spectrophotometric method is an acceptable alternative to HPLC. With respect to C. steveni, the leaves contained the largest amount of colchicine (0.204/100 g), whilst in C. hierosolymitanum corms showed the highest colchicine content (0.126/100 g). As a source of colchicine, the two investigated species showed levels comparable with those found in C. autumnale, the traditional source of colchicine. Copyright © 2004 John Wiley & Sons, Ltd.
Simultaneous quantitative determination of eight triterpenoid monoesters from flowers of 10 varieties of Calendula ofﬁcinalis L. and characterisation of a new triterpenoid monoester
Authors: Neukirch Hannes , D'Ambrosio Michele , Via Josef Dalla , Guerriero Antonio 
Published: January 2004

AbstractDichloromethane extracts of dried ﬂowers of Calendula ofﬁcinalis contain eight known bioactive triterpendiol monoesters, namely, faradiol‐3‐O‐palmitate, faradiol‐3‐O‐myristate, faradiol‐3‐O‐laurate, arnidiol‐3‐O‐palmitate, arnidiol‐3‐O‐myristate, arnidiol‐3‐O‐laurate, calenduladiol‐3‐O‐palmitate and calenduladiol‐3‐O‐myristate. These pentacyclic terpenoids have been quantiﬁed simultaneously using reversed‐phase HPLC with isocratic elution and internal standardisation. Of the 10 varieties of C. ofﬁcinalis investigated, Calypso Orange Florensis produced the highest amounts of the bioactive monoesters, followed by Fiesta Gitana Gelb and May Orange Florensis. The lipophilic extract from the ﬂowers of Calypso Orange Florensis variety also contained low levels of the newly characterised calenduladiol‐3‐O‐laurate. Copyright © 2004 John Wiley & Sons, Ltd.
Identiﬁcation and quantiﬁcation of components in extracts of Uncaria tomentosa by HPLC‐ES/MS
Authors: Montoro P. , Carbone V. , de Dioz Zuniga Quiroz J. , De Simone F. , Pizza C. 
Published: January 2004

AbstractThe two main classes of secondary metabolites, alkaloids and quinovic acid glycosides, of Uncaria tomentosa (Willd.) DC. (Rubiaceae), a Peruvian plant commonly known as ‘uña de gato’, have been analysed. Separation of the alkaloidal fraction was achieved using a solid phase extraction method based on cationic exchange, and an analytical method employing HPLC‐ES/MS has been developed. Quantitative data for commercial wild bark, cultivated bark and leaves are reported. The analysis of quinovic acid glycosides was performed directly on the crude extract using both a fast analytical method based on ﬂow injection ES/MS, and a more complete analytical technique using HPLC‐MS. Copyright © 2004 John Wiley & Sons, Ltd.
Screening for oestrogenic activity of plant and food extracts using in vitro trout hepatocyte cultures
Authors: Bennetau‐Pelissero C. , Gontier Latonnelle K. , Lamothe V. , Shinkaruk‐Poix S. , Kaushik S. J. 
Published: January 2004

AbstractThe use of in vitro trout hepatocyte cultures is shown to provide a simple and effective way to screen plant and food products for oestrogenic activity. The relative oestrogenic activities of 0.1 g each of extracts of phytosterol, soy isoﬂavone, red clover, kudzu and soybean extracts were determined using this assay and found to be equivalent to 212, 1, 3.2, 132 and 1025 nm of 17β‐estradiol, respectively. Controls were performed on soybean and kudzu extracts using speciﬁc ELISAs for isoﬂavones and these conﬁrmed the validity of the cell culture assay. The method described offers an advantage over current methods in that it can detect increased oestrogenic activity that may occur as a result of metabolic activation of pre‐ or pro‐oestrogens liver cells. Copyright © 2004 John Wiley & Sons, Ltd.
Supercritical carbon dioxide extraction of selected medicinal plants—effects of high pressure and added ethanol on yield of extracted substances
Authors: Hamburger M. , Baumann D. , Adler S. 
Published: January 2004

AbstractThe possibilities and limitations of supercritical ﬂuid extraction of natural products of low, medium and high polarity under very high pressure and with polar modiﬁers has been investigated. The medicinal herbs marigold (Calendula ofﬁcinalis), hawthorn (Crataegus sp.) and chamomile (Matricaria recutita) were used as models in this study. Extraction proﬁles and the spectra of extractable metabolites were recorded following extraction with mixtures of carbon dioxide:ethanol of varying proportions (0–20% ethanol) and at various pressures in the range 300–689 bar. Components were identiﬁed by HPLC‐PAD‐MS or GC‐MS and quantiﬁed by HPLC or GC as appropriate. Extraction yields under the varying conditions depended to a large extent on the proﬁles of secondary metabolites present in the three drugs. Whereas the extractability of lipophilic compounds increased substantially at pressures above 300 bar, the yields of polyphenolic and glycosidic compounds remained low even at 689 bar and with 20% modiﬁer in the extraction ﬂuid. Copyright © 2004 John Wiley & Sons, Ltd.
Validation of a capillary electrophoresis method for the quantitative determination of free and total apigenin in extracts of Chamomilla recutita
Authors: Fonseca Fabiana N. , Tavares Marina F. M. 
Published: January 2004

AbstractA capillary electrophoretic method for the quantiﬁcation of free and total apigenin in methanolic, ethanolic and glycolic extracts of Chamomilla recutita L. Rauschert (Asteraceae) is described. The method was validated for measurement of apigenin in the range 5.00–300 µg/mL (r2 = 0.993) and showed coefﬁcients of intra‐day (replicability) and inter‐day (repeatability) variability of better than 2%. The limits of detection and quantiﬁcation were 3.80 and 11.5 µg/mL, respectively, and the average recovery was 102.0 ± 0.8% at three concentration levels of apigenin. Free and total apigenin contents in the extracts were, respectively, determined as 106 and 903 µg/g (methanolic extract), 77 and 817 µg/g (ethanolic extract) and 11.0 and 247 µg/g (glycolic extract). Copyright © 2004 John Wiley & Sons, Ltd.