bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recognition, presence, and survival of locust central nervous glia in situ and in vitro
Authors: Gocht Daniela , Wagner Simone , Heinrich Ralf 
Published: December 2008

AbstractInsect glial cells serve functions for the formation, maintenance, and performance of the central nervous system in ways similar to their vertebrate counterparts. Characterization of physiological mechanisms that underlie the roles of glia in invertebrates is largely incomplete, partly due to the lack of markers that universally label all types of glia throughout all developmental stages in various species. Studies on primary cell cultures from brains of Locusta migratoria demonstrated that the absence of anti‐HRP immunoreactivity, which has previously been used to identify glial cells in undissociated brains, can also serve as a reliable glial marker in vitro, but only in combination with a viability test. As cytoplasmic membranes of cultured cells are prone to degradation when they lose viability, only cells that are both anti‐HRP immunonegative and viable should be regarded as glial cells, whereas the lack of anti‐HRP immunoreactivity alone is not sufficient. Cell viability can be assessed by the pattern of nuclear staining with DAPI (4′,6‐diamidino‐2‐phenylindole), a convenient, sensitive labeling method that can be used in combination with other immunocytochemical cellular markers. We determined the glia‐to‐neuron ratio in central brains of fourth nymphal stage of Locusta migratoria to be 1:2 both in situ and in dissociated primary cell cultures. Analysis of primary cell cultures revealed a progressive reduction of glial cells and indicated that dead cells detach from the substrate and vanish from the analysis. Such changes in the composition of cell cultures should be considered in future physiological studies on cell cultures from insect nervous systems. Microsc. Res. Tech. 2009. © 2008 Wiley‐Liss, Inc.
Purinergic receptor activation evokes neurotrophic factor neuropeptide Y release from neonatal mouse olfactory epithelial slices
Authors: Kanekar Shami , Jia Cuihong , Hegg Colleen Cosgrove 
Published: December 2008

AbstractOne premise regarding the mechanism of injury‐evoked neuroregeneration is that injured cells induce the release of neurotrophic factors to trigger neurogenesis. Extracellular purine nucleotides exert multiple neurotrophic actions in the central nervous system mediated via activation of purinergic receptors. However, whether purinergics have a neurotrophic role in the olfactory neuroepithelium has not been investigated. Thus, we monitored the ATP‐induced release of neuropeptide Y (NPY), a neuropeptide that increases neuroproliferation in the olfactory epithelium. To visualize NPY release, slices of olfactory epithelium from neonatal mice were cultured on nitrocellulose paper. Immunoassays of the nitrocellulose demonstrated NPY immunoreactivity in regions corresponding to the olfactory epithelium of the nasal cavity. One hour of exposure to exogenous ATP (100, 500 μM) significantly increased the number of olfactory epithelium slices that released NPY from 25% ± 6% to 60% ± 7% or 71% ± 10% (P= 0.001). The purinergic receptor antagonists pyridoxalphosphate‐6‐azophenyl‐2′,4′‐disulfonic acid (PPADS; 25 μM) and suramin (100 μM) significantly reduced the number of olfactory epithelium slices exhibiting ATP‐evoked NPY release to 18% ± 11% (P= 0.004), indicating that NPY release is mediated by activation of purinergic receptors. Released NPY was quantified by enzyme and radioimmunoassays. Exogenous ATP or UTP significantly increased the amount of NPY released. Overall, this study demonstrates that purinergic receptor activation mediates the release of neurotrophic factor NPY in the olfactory epithelium and provides pharmacological targets to promote regeneration of damaged olfactory epithelium. © 2008 Wiley‐Liss, Inc.
The neuronal apoptotic death in global cerebral ischemia in gerbil: Important role for sodium channel modulator
Authors: Brahma Manoja Kumar , Dohare Preeti , Varma Saurabh , Rath Srikanta Kumar , Garg Puja , Biswal Prasanta Kumar , Chowdhury Piyali Dhar , Ray Madhur 
Published: December 2008

AbstractGlobal ischemia was induced in gerbil by bilateral occlusion of the common carotid arteries for 5 min. Sodium ionophore monensin or sodium channel blocker tetrodotoxin (TTX) was administered at doses of 10 μg/kg, i.p., 30 min before ischemia induction; the dose was repeated after 22 hr. Subsequently, brain infarct occurred, determined at 24 hr after occlusion. Large, well‐demarcated infarcts were observed in both hemispheres, an important observation because it critically influences the interpretation of the data. Because nitric oxide (NO) production is thought to be related to ischemic neuronal damage, we examined increases in Ca2+ influx, which lead to the activation of nitric oxide synthase (NOS). Then we evaluated the contributions of neuronal NOS, endothelial NOS, and inducible NOS to NO production in brain cryosections. The cytosolic release of apoptogenic molecules like cytochrome c and p53 were confirmed after 24 hr of reflow. TUNEL (terminal deoxynucleotidyl transferase dUTP nick‐end labeling) labeling detected the apoptotic cells, which were confirmed in neuron‐rich cell populations. After 24 hr, all the ischemic changes were amplified by monensin and significantly attenuated by TTX treatment. Additionally, the nesting behavior and histological outcomes were examined after 7 day of reflow. The neuronal damage in the hippocampal area and significant decrease in nesting scores were observed with monensin treatment and reduced by TTX pretreatment after day 7 of reflow. To our knowledge, this report is the first to highlight the involvement of the voltage‐sensitive Na+ channel in possibly regulating in part NO system and apoptosis in a cytochrome c–dependent manner in global ischemia in the gerbil, and thus warrants further investigation. © 2008 Wiley‐Liss, Inc.
Fyn kinase is involved in oligodendroglial cell differentiation induced by apotransferrin
Authors: Perez M.J. , Ortiz E.H. , Roffé M. , Soto E.F. , Pasquini J.M. 
Published: December 2008

AbstractMechanisms that regulate oligodendroglial cell (OLGc) differentiation are the focus of intensive research in the field of cellular and molecular neurobiology. We have previously shown that the addition of apotransferrin (aTf) to primary OLGc cultures accelerates their differentiation and induces an increase in the expression of different components of the myelin cytoskeleton (CSK) such as actin, tubulin, and some of the microtubule‐associated proteins, particularly the stable tubulin only peptide (STOP). Fyn protein‐tyrosine kinase (Fyn kinase), a member of the Src family, participates in signalling pathways that regulate OLGs/myelin cytoskeletal reorganization. It is essential for myelin development in the central nervous system (CNS), and its absence results in hypomyelination. In the present study, we used both primary cell and N19 cell line cultures to investigate further the mechanisms of action involved in the accelerated differentiation of OLGcs induced by aTf. In particular, we were interested in studying the participation of Fyn kinase in the different pathways involved in the reorganization of the OLGc/myelin cytoskeleton. In agreement with results already published, we found that in OLGcs, Fyn kinase is associated with Tau and tubulin. Using a dominant‐negative of Tau in which the Fyn‐Tau‐microtubules (MTs) interaction is blocked, we found that aTf was unable to induce OLGc morphological differentiation. It was also observed that aTf decreases the activated RhoA content in coincidence with a redistribution of actin immunoreactivity. These results give support to our hypothesis that Fyn kinase plays a key role in the differentiation process of OLGcs promoted by aTf. © 2008 Wiley‐Liss, Inc.
In vivo infusion of UTP and uridine to the deafened guinea pig inner ear: Effects on response thresholds and neural survival
Authors: Fransson Anette , Järlebark Leif E. , Ulfendahl Mats 
Published: December 2008

AbstractNucleotides and nucleosides are known to function as neurotransmitters and neuromodulators but have recently been shown to have a trophic effect on neurons. It has previously been shown, in an animal model for cochlear implants, that local infusion of neurotrophic factors intervenes with the degenerative processes occurring after deafening and protects the auditory spiral ganglion neurons so that electrical responsiveness is maintained. Here we test the hypothesis that nucleosides and nucleotides have a similar effect on the acutely damaged inner ear. Pigmented guinea pigs received a cochlear implant electrode for measuring electrically evoked auditory brainstem responses and a miniosmotic pump for delivering drugs directly to the cochlea. The animals were deafened by a 48‐hr infusion with 10% neomycin, followed by 23 days of treatment with primarily UTP, uridine nucleotides, or as control artificial perilymph. Electrically evoked responses were measured weekly, and at the end of the experiment the cochleae were collected and processed for morphological analysis and spiral ganglion neuron counting. Both UTP‐ and uridine‐treated groups showed significantly better response after 23 days of treatment compared with the control group. The densities of spiral ganglion neuron were significantly higher for both treated groups compared with the control group treated with artificial perilymph. The results demonstrate that UTP and uridine rescue auditory neurons and suggest that drugs acting on purinoceptors could be of clinical importance. © 2008 Wiley‐Liss, Inc.
Vessel microport technique for applications in cerebrovascular research
Authors: Chen Lei , Swartz Karin R. , Toborek Michal 
Published: December 2008

AbstractCerebrovascular research suffers from a lack of reliable methods with which to deliver exogenous substances effectively into the central nervous system (CNS) of small experimental animals. Here we describe a novel vessel microport surgical technique for a variety of cerebrovascular applications that is reproducible and well tolerated in mice. The procedure is based on the insertion of a vessel microport into the external carotid artery for substance delivery into the CNS via the internal carotid artery. The method results in selective substance delivery into the ipsilateral hemisphere. Other novel aspects of this surgical technique include the ability to perform multiple injections, study of conscious mice well removed from surgery, and lack of occlusion of the common or internal carotid artery that allows carotid flow to be maintained. The feasibility of this technique has been validated by infusion of HIV Tat protein to induce permeability of the blood–brain barrier and by implantation of tumor cells to establish a brain metastasis model. Thus, the described vessel microport technique can be employed in a variety of cerebrovascular research applications. © 2008 Wiley‐Liss, Inc.
MRG15, a component of HAT and HDAC complexes, is essential for proliferation and differentiation of neural precursor cells
Authors: Chen Meizhen , Takano‐Maruyama Masumi , Pereira‐Smith Olivia M. , Gaufo Gary O. , Tominaga Kaoru 
Published: December 2008

AbstractNeurogenesis during development depends on the coordinated regulation of self‐renewal and differentiation of neural precursor cells (NPCs). Chromatin regulation is a key step in self‐renewal activity and fate decision of NPCs. However, the molecular mechanism or mechanisms of this regulation is not fully understood. Here, we demonstrate for the first time that MRG15, a chromatin regulator, is important for proliferation and neural fate decision of NPCs. Neuroepithelia from Mrg15‐deficient embryonic brain are much thinner than those from control, and apoptotic cells increase in this region. We isolated NPCs from Mrg15‐deficient and wild‐type embryonic whole brains and produced neurospheres to measure the self‐renewal and differentiation abilities of these cells in vitro. Neurospheres culture from Mrg15‐deficient embryo grew less efficiently than those from wild type. Measurement of proliferation by means of BrdU (bromodeoxyuridine) incorporation revealed that Mrg15‐deficient NPCs have reduced proliferation ability and apoptotic cells do not increase during in vitro culture. The reduced proliferation of Mrg15‐deficient NPCs most likely accounts for the thinner neuroepithelia in Mrg15‐deficient embryonic brain. Moreover, we also demonstrate Mrg15‐deficient NPCs are defective in differentiation into neurons in vitro. Our results demonstrate that MRG15 has more than one function in neurogenesis and defines a novel role for this chromatin regulator that integrates proliferation and cell‐fate determination in neurogenesis during development. © 2008 Wiley‐Liss, Inc.
Effect of estradiol on striatal dopamine activity of female hemiparkinsonian monkeys
Authors: Morissette Marc , Di Paolo Thérèse 
Published: December 2008

AbstractA higher prevalence and incidence of Parkinson's disease is observed in men, and beneficial motor effects of estrogens are observed in parkinsonian women. In rodents, an effect of estradiol on dopamine systems is documented, whereas much less is known in monkeys. Enkephalin was shown to exert a compensatory modulatory effect on the denervated dopamine nigrostriatal pathway in monkeys and in humans. Moreover in rodents, striatal preproenkephalin mRNA is increased by estrogen treatment. Hence, we investigated the responsiveness of striatal dopamine to estradiol in long‐term ovariectomized monkeys bearing a unilateral lesion with 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) to mimic parkinsonian postmenopausal women. Seven ovariectomized female monkeys received a unilateral MPTP lesion; 4 years after ovariectomy, three received 1‐month treatment with 17β‐estradiol and the others received vehicle. The lesioned striata showed extensive denervation in all monkeys as measured with dopamine and metabolite concentrations assayed by high‐performance liquid chromatography and by autoradiography of the dopamine transporter. The lesioned and intact striata of estradiol‐treated monkeys had increased 3‐methoxytyramine, and lesioned putamen increased dopamine concentrations compared with vehicle‐treated monkeys. Estradiol treatment increased the dopamine transporter in subregions of the intact caudate and putamen compared with the intact striata of vehicle‐treated monkeys, but not in the lesioned striata. Preproenkephalin mRNA levels measured by in situ hybridization were increased in the lesioned striata of vehicle treated monkeys and were not further enhanced in estradiol‐treated monkeys. These results show that long after ovariectomy, modeling postmenopausal hormonal conditions, brain dopamine metabolism, and transporter are still responsive to estradiol. © 2008 Wiley‐Liss, Inc.
Contribution of the striatum to the effects of 5‐HT1A receptor stimulation in L‐DOPA‐treated hemiparkinsonian rats
Authors: Bishop Christopher , Krolewski David M. , Eskow Karen L. , Barnum Christopher J. , Dupre Kristin B. , Deak Terrence , Walker Paul D. 
Published: December 2008

AbstractClinical and experimental studies implicate the use of serotonin (5‐HT)1A receptor agonists for the reduction ofL‐3,4‐dihydroxyphenylalanine (L‐DOPA)‐induced dyskinesia (LID). Although raphe nuclei likely play a role in these antidyskinetic effects, an unexplored population of striatal 5‐HT1A receptors (5‐HT1AR) may also contribute. To better characterize this mechanism, L‐DOPA‐primed hemiparkinsonian rats received the 5‐HT1AR agonist ±8‐OH‐DPAT (0, 0.1, 1.0 mg/kg, i.p.) with or without cotreatment with the 5‐HT1AR antagonist WAY100635 (0.5 mg/kg, i.p.) 5 min after L‐DOPA, after which abnormal involuntary movements (AIMs), rotations, and forelimb akinesia were quantified. To establish the effects of 5‐HT1AR stimulation on L‐DOPA‐induced c‐fos and preprodynorphin (PPD) mRNA within the dopamine‐depleted striatum, immunohistochemistry and real‐time reverse transcription polymerase chain reaction, respectively, were used. Finally, to determine the contribution of striatal 5‐HT1AR to these effects, L‐DOPA‐primed hemiparkinsonian rats received bilateral intrastriatal microinfusions of ±8‐OH‐DPAT (0, 5, or 10 μg/side), WAY100635 (5 μg/side), or both (10 μg + 5 μg/side) 5 min after L‐DOPA, after which AIMs and rotations were examined. Systemic ±8‐OH‐DPAT dose‐ and receptor‐dependently attenuated L‐DOPA‐mediated AIMs and improved forelimb akinesia. Striatal c‐fos immunoreactivity and PPD mRNA ipsilateral to the lesion were strongly induced by L‐DOPA, while ±8‐OH‐DPAT suppressed these effects. Finally, intrastriatal infusions of ±8‐OH‐DPAT reduced AIMs while coinfusion of WAY100635 reversed its antidyskinetic effect. Collectively, these results support the hypothesis that the cellular and behavioral properties of 5‐HT1AR agonists are conveyed in part via a population of functional 5‐HT1AR within the striatum. © 2008 Wiley‐Liss, Inc.
Rural tourism development in China
Authors: Gao Shunli , Huang Songshan , Huang Yucheng 
Published: December 2008

AbstractThis paper provides an overview and brief evaluation of China's rural tourism. Beginning with the form of poverty alleviation through tourism, China's rural tourism has undergone over 20 years of development and exhibited some unique features in its development pattern, scale and business operational models in accordance with China's political, social and economic systems. Government plays a decisive role in developing rural tourism in China. However, rural tourism has been valued mainly as an economic means for rural development during the country's modernisation process. Overlooking rurality as an essential issue in rural tourism may lead development to a wrong direction, which could jeopardise the sustainability of the industry. Copyright © 2008 John Wiley & Sons, Ltd.
Expanding the destination image: wine tourism in the Canary Islands
Authors: Scherrer Pascal , Alonso Abel , Sheridan Lynnaire 
Published: December 2008

AbstractTourism to the Canary Islands is centred around competitively priced holidays focused on the sun and beach mass tourism experience. A restructure of the islands' wine industry offers opportunities for developing new tourism alternatives based on gourmet products and traditional landscapes. This paper examines the potential of wine tourism from winery operators' perspectives. Challenges to overcome in the development of a successful sustainable local wine tourism industry include the need for expansion of the destination image to reflect the region's wine‐making history and scenic qualities; a shift towards independent high‐yield travellers; and reintroducing local produce in the mass tourism product. Copyright © 2008 John Wiley & Sons, Ltd.
Changes in plant diversity, biomass and soil C, in alpine meadows at different degradation stages in the headwater region of three rivers, China
Authors: Wang C. T. , Long R. J. , Wang Q. L. , Jing Z. C. , Shi J. J. 
Published: December 2008

AbstractField surveys and experiment analyses were applied to detect the relationships between plant diversity, community biomass and soil resources at different degradation successional stages in the headwater region of three rivers in an alpine meadow. The chronosequence approach (space‐for‐time substitution) is a viable tool for obtaining integrated information within successional studies. The experimental plots were located in the Guoluo area, which is part of the source region for the Yangtze and Yellow Rivers. The results showed not only that the quantities of roots and soil that are ‘carriers’ for cultivating soil roots were altered not only by disturbance (including overgrazing) and environmental factors but also that the proportion of the rhizome to soil at the 0–10 cm soil layer was enhanced by disturbance in heavy degradation. The plant community composition changed, and the number of plant species and the proportions of fine forage decreased. Moreover, soil fertility levels decreased remarkably, and the soil was degenerated. Plant community biomass levels at different degradation successional stages affected the soil microbial biomass carbon, soil organic carbon and also affected soil fertility conditions. Soil organic carbon and soil total nitrogen declined with grassland degeneration, and the distribution of soil organic carbon was influenced greatly. The alpine speciesKobresia pygmaeawas at different degradation successional stages, and the plant community biomass was significantly related to soil nutrients. In the positive successional series, the composition of plant functional groups became complex gradually, plant species richness was gradually enhanced, and the change in the composition of each plant functional group also reflected the restoration degree plant community structure. Copyright © 2008 John Wiley & Sons, Ltd.
Simple devices for measuring complex ultrashort pulses
Authors: Trebino R. , Bowlan P. , Gabolde P. , Gu X. , Akturk S. , Kimmel M. 
Published: December 2008

AbstractWe describe experimentally simple, accurate, and reliable methods for measuring from very simple to potentially very complex ultrashort laser pulses. With only a few easily aligned components, these methods allow the measurement of a wide range of pulses, including those with time‐bandwidth products greater than 1000 and those with energies of only a few hundred photons. In addition, two new, very simple methods allow the measurement of the complete spatio‐temporal intensity and phase of even complex pulses on a single shot or at a tight focus.
Photonic crystal LEDs – designing light extraction
Authors: Wiesmann C. , Bergenek K. , Linder N. , Schwarz U.T. 
Published: December 2008

AbstractPhotonic crystals (PhCs) have attracted much attention during the last decade as a solution to overcome the low extraction efficiency of as‐grown light‐emitting diodes (LEDs). In this review we describe the underlying physics and summarize recent results obtained with PhC LEDs. Here, the main focus is on diffracting PhC. In order to quantify the benefit from the incorporation of PhCs for diffracting light a comparison by simulations between a PhC LED and a standard state‐of‐the‐art LED is carried out. Finally, the impact of the PhC on the LEDs emission characteristics will be discussed with respect to étendue‐limited applications.
PAMAM Dendrimers as Potential Agents against Fibrillation ofα‐Synuclein, a Parkinson's Disease‐Related Protein
Authors: Rekas Agata , Lo Victor , Gadd Gerry E. , Cappai Roberto , Yun Seok I. 
Published: December 2008

AbstractThe effect of PAMAM dendrimers (generations G3, G4 and G5) on the fibrillation ofα‐synuclein was examined by fluorescence and CD spectroscopy, TEM and SANS. PAMAM dendrimers inhibited fibrillation ofα‐synuclein and this effect increased both with generation number and PAMAM concentration. SANS showed structural changes in the formed aggregates ofα‐synuclein – from cylindrical to dense three‐dimensional ones – as the PAMAM concentration increased, on account of the inhibitory effect. PAMAM also effectively promoted the breaking down of pre‐existing fibrils ofα‐synuclein. In both processes – that is, inhibition and disassociation of fibrils – PAMAM redirectedα‐synuclein to an amorphous aggregation pathway.magnified image