bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trauma to erythrocytes induced by long term in vitro pumping using a roller pump
Authors: Ding M.J. , Xu S.W. , Zhang J. , Wang Q. , Chang Y. , Chen F. , Zeng Y.J. 
Published: January 2007

AbstractThe objective of this study is to investigate the impact of trauma on erythrocyte caused by long term in vitro pumping using roller pump. Ten bags of human blood (400 ml each) were provided by a local blood bank and they were divided into two groups with five bags in each group. Each blood bag was subject to pumping in a closed circuit, which was composed of silica gel tubes and a roller pump. Polystan and COBE pumps were used for the two groups, respectively. The blood was pumped for 16 h in vitro. Free hemoglobin (FHb), platelets (PLT), erythrocyte fragility (EF), and morphological analysis of erythrocytes observed under scanning electron microscope were measured to evaluate the impact of trauma on erythrocytes. A small amount of blood was collected for analysis before pumping, at the end of the 4th hour and then every 2 h till the end of the 16th hour. Some blood samples were also collected for electron microscope scanning before pumping and every 4 h during pumping. It was found that FHb and PLT linearly increased with the pumping time. There was a significant correlation between the two parameters (r= 0.7745, p< 0.001). The hemolysis indexes of the two groups were 0.296 and 0.3993 mg/L/h, respectively, with no significant difference. During the pumping process, EF changed slightly. The observation of scanning electron microscopy showed various deformed erythrocytes after pumping, including the distortion of cell membrane and the appearance of echinocytes, which increased with pumping time. This study demonstrated that long term pumping using roller pump not only caused the immediate rupture of red blood cells, i.e. the immediate hemolysis, but also caused sub‐trauma to a large number of erythrocytes, which led to the delayed hemolysis. The change of erythrocyte morphology was the basis of the delayed hemolysis.
Climate variability in the Aral Sea basin (Central Asia) during the late Holocene based on vegetation changes
Authors: Sorrel Philippe , Popescu Speranta-Maria , Klotz Stefan , Suc Jean-Pierre , Oberhänsli Hedi 
Published: January 2007

AbstractHigh-resolution pollen analyses (∼ 50 yr) from sediment cores retrieved at Chernyshov Bay in the NW Large Aral Sea record shifts in vegetational development from subdesertic to steppe vegetation in the Aral Sea basin during the late Holocene. Using pollen data to quantify climatic parameters, we reconstruct and date for the first time significant changes in moisture conditions in Central Asia during the past 2000 yr. Cold and arid conditions prevailed between ca. AD 0 and 400, AD 900 and 1150, and AD 1500 and 1650 with the extension of xeric vegetation dominated by steppe elements. These intervals are characterized by low winter and summer mean temperatures and low mean annual precipitation (Pmm< 250 mm/yr). Conversely, the most suitable climate conditions occurred between ca. AD 400 and 900, and AD 1150 and 1450, when steppe vegetation was enriched by plants requiring moister conditions (Pmm∼ 250–500 mm/yr) and some trees developed. Our results are fairly consistent with other late Holocene records from the eastern Mediterranean region and the Middle East, showing that regional rainfall in Central Asia is predominantly controlled by the eastern Mediterranean cyclonic system when the North Atlantic Oscillation (NAO) is in a negative phase.
An assessment of human versus climatic impacts on Holocene soil erosion in NE Peloponnese, Greece
Authors: Fuchs M. 
Published: January 2007

AbstractSoil erosion is a natural geomorphological process, which can be triggered by both natural (climate, tectonics, or both) and anthropogenic (e.g., agriculture) perturbation of the ecosystem. Evidence has accrued that the Holocene climate experienced large fluctuations in amplitude and suggestions of human impact on the ecosystem provided by the Neolithic revolution dating back to the early Holocene have been made. The question of whether man or climate was the dominant factor responsible for Holocene soil erosion remains unresolved. To resolve the reasons for Holocene sediment redistribution, high-resolution chronometric data on sediments derived from colluvial and alluvial archives from southern Greece were obtained and combined with available archaeological and paleoclimatic data from the eastern Mediterranean. These data show a significant correlation between sedimentation rates and settlement history. Climatic fluctuations are only weakly correlated with sedimentation history. The results show high sedimentation rates during the Early Neolithic (7th millennium BC) in southern Greece, suggesting that Holocene soil erosion was triggered by human activity and then amplified by enhanced precipitation. This would explain the high sedimentation rates during the Early Neolithic in connection with enhanced precipitation in the eastern Mediterranean, which continued until the mid-Holocene.
Dendrimers as multi-purpose nanodevices for oncology drug delivery and diagnostic imaging
Authors: Tomalia D.A. , Reyna L.A. , Svenson S. 
Published: January 2007

Dendrimers are routinely synthesized as tuneable nanostructures that may be designed and regulated as a function of their size, shape, surface chemistry and interior void space. They are obtained with structural control approaching that of traditional biomacromolecules such as DNA/RNA or proteins and are distinguished by their precise nanoscale scaffolding and nanocontainer properties. As such, these important properties are expected to play an important role in the emerging field of nanomedicine. This review will describe progress on the use of these features for both targeted diagnostic imaging and drug-delivery applications. Recent efforts have focused on the synthesis and pre-clinical evaluation of a multipurpose STARBURST® PAMAM (polyamidoamine) dendrimer prototype that exhibits properties suitable for use as: (i) targeted, diagnostic MRI (magnetic resonance imaging)/NIR (near-IR) contrast agents, (ii) and/or for controlled delivery of cancer therapies. Special emphasis will be placed on the lead candidate, namely [core: 1,4-diaminobutane; G (generation)=4.5], [dendri-PAMAM(CO2Na)64]. This dendritic nanostructure (i.e. ∼5.0 nm diameter) was selected on the basis of a very favourable biocompatibility profile [The Nanotechnology Characterization Laboratory (NCL), an affiliate of the National Cancer Institute (NCI), has completed extensive in vitro studies on the lead compound and have found it to be very benign, non-immunogenic and highly biocompatible], the expectation that it will exhibit desirable mammalian kidney excretion properties and demonstrated targeting features.
The Microscopic Theory of Superconductivity–Verifications and Extensions
Authors: Tord Claeson  , Stig Lundqvist  
Published: January 2007

The microscopic theory of superconductivity was formulated in 1957 by Bardeen, Cooper, and Schrieffer. In the BCS model, the ground state of super electrons is built up by pairs kept together by an attractive interaction. An exchange of phonons can give such an attraction. The electrons in the superconducting condensate are correlated within a macroscopic distance. To excite electrons, or break pairs, a certain gap energy is needed.A number of experimental confirmations were discussed already in the original paper. The BCS theory initiated many experiments. Some of them provided a stimulus to logical extensions of the theory. These have mainly been concerned with a more realistic, energy-and momentum-dependent interaction than the original approximation. Lifetime aspects are also of importance.In this short survey we describe the results of a few experiments that test the concepts of pairing, energy gap and phonon-mediated attraction. The main emphases are on the powerful tunneling method and the variation of the superconducting transition temperature with different physical and chemical parameters.
Classification du Spectre d'Arc du Sélénium (Sel) entre 3 900 et 11 844 cm-1
Authors: C Morillon  , J Vergès  
Published: January 2007

The spectrum emitted by an electrodeless discharge tube filled with pure80Se has been newly investigated by Fourier transform spectroscopy. The observations have led to a list of wavenumbers and estimated intensities for 360 lines in the range 3 900 to 11 844 cm-1. The values of the known energy levels involved in the observed transitions have been improved by exploiting the high wavenumber accuracy, 3 × 10-3cm-1. The fine structures of the 4p3(4S)nd5Dand3Dterms have been improved and 3 levels withJ=0 are new. The fine structures of the 4p3(4S)nf5Fand5Fterms, which were not resolved in previous studies, are given fromn=4 ton=6. It is shown that the principal quantum numbersnare in error by one unit in the compilation Atomic Energy Levels Vol. II (1952). Finally, the very regular 4p3(4S)nf5F5series yields for the principal ionization energy of Se I the value:IP = 78 658.12 ± 0.1 cm-1(9.747 ± 0.001 eV).
Activation of sphingosine‐1‐phosphate receptor S1P5 inhibits oligodendrocyte progenitor migration
Authors: Novgorodov Alexander S. , El‐Awani Mazen , Bielawski Jacek , Obeid Lina M. , Gudz Tatyana I. 
Published: January 2007

ABSTRACTSphingosine‐1‐phosphate (S1P) acts as an extracellular ligand for a family of G‐protein coupled receptors that are crucial in cell migration. S1P5 is exclusively expressed in oligodendrocytes and oligodendrocyte precursor cells (OPCs), which migrate considerable distances during brain development. The current studies suggest a physiological role for S1P and S1P5 in regulation of OPC migration. mRNA expression levels of S1P2 and S1P5 are comparable in OPCs, but S1P binding specifically to the S1P5 receptor blocked OPC migration (IC50 = 29 nM). Thus, knocking down S1P5 using siRNA prevented the S1P‐induced decrease in OPC migration, whereas knocking down S1P2 did not have any effect. S1P‐induced modulation of OPC migration was insensitive to pertussis toxin, suggesting that S1P5‐initiated signaling is not mediated by the Gαi‐protein coupled pathway. Furthermore, S1P5 appears to engage the Gα12/13 protein coupled Rho/ROCK signaling pathway to impede OPC migration. To modulate OPC motility, extracellular S1P could be derived from the export of intracellular S1P generated in response to glutamate treatment of OPCs. These studies suggest that S1P could be a part of the neuron‐oligodendroglial communication network regulating OPC migration and may provide directional guidance cues for migrating OPCs in the developing brain.—Novgorodov A. S., El‐Alwani, M., Bielawski, J., Obeid, L. M., Gudz T. I. Activation of sphingosine‐1‐phosphate receptor S1P5 inhibits oligodendrocyte progenitor migration. FASEB J. 21, 1503–1514 (2007)
Functional relevance of DNA polymorphisms within the promoter region of the prion protein gene and their association to BSE infection
Authors: Kashkevich Kseniya , Humeny Andreas , Ziegler Ute , Groschup Martin H. , Nicken Petra , Leeb Tosso , Fischer Christine , Becker Cord-Michael , Schiebel Katrin 
Published: January 2007

ABSTRACTTransmissible spongiform encephalopathies (TSEs) are a group of neurodegenerative diseases that can occur spontaneously or can be caused by infection or mutations within the prion protein gene PRNP. Nonsynonymous DNA polymorphisms within the PRNP gene have been shown to influence susceptibility/resistance to infection in sheep and humans. Analysis of DNA polymorphisms within the core promoter region of the PRNP gene in four major German bovine breeds resulted in the identification of both SNPs and insertion/deletion (indel) polymorphisms. Comparative genotyping of both controls and animals that tested positive for bovine spongiform encephalopathy (BSE) revealed a significantly different distribution of two indel polymorphisms and two SNPs within Braunvieh animals, suggesting an association of these polymorphisms with BSE susceptibility. The functional relevance of these polymorphisms was analyzed using reporter gene constructs in neuronal cells. A specific haplotype near exon 1 was identified that exhibited a significantly lower expression level. Genotyping of nine polymorphisms within the promoter region and haplotype calculation revealed that the haplotype associated with the lowest expression level was underrepresented in the BSE group of all breeds compared to control animals, indicating a correlation of reduced PRNP expression and increased resistance to BSE.—Kashkevich K., Humeny, A., Ziegler, U., Groschup, M. H., Nicken, P., Leeb, T., Fischer, C., Becker, C.‐M., Schiebel K. Functional relevance of DNA polymorphisms within the promoter region of the prion protein gene and their association to BSE infection. FASEB J. 21, 1547–1555 (2007)
The tobacco Ntann12 gene, encoding an annexin, is induced upon Rhodoccocus fascians infection and during leafy gall development
Authors: VANDEPUTTE OLIVIER , LOWE YVES OUKOUOMI , BURSSENS SYLVIA , VAN RAEMDONCK DAMIEN , HUTIN DAVID , BONIVER DELPHINE , GEELEN DANNY , EL JAZIRI MONDHER , BAUCHER MARIE 
Published: January 2007

SUMMARYAnnexins are calcium‐binding proteins that have been associated in plants with different biological processes such as responses to abiotic stress and early nodulation stages. Until now, the implication of annexins during plant–pathogen interactions has not been reported. Here, a novel plant annexin gene induced in tobacco BY‐2 cell suspension cultures infected with the phytopathogenic bacterium Rhodococcus fascians (strain D188) has been identified. Expression of this gene, called Ntann12, is also induced, but to a lower extent, by a strain (D188‐5) that is unable to induce leafy gall formation. This gene was also induced in BY‐2 cells infected with Pseudomonas syringae but not in cells infected with Agrobacterium tumefaciens or Escherichia coli. Ntann12 expression was also found to be stimulated by abiotic stress, including NaCl and abscissic acid, confirming a putative role in stress signal transduction pathways. In addition, promoter‐GUS analyses using homozygous transgenic tobacco seedlings showed that the developmentally controlled expression of Ntann12 is altered upon R. fascians infection. Finally, up‐regulation of Ntann12 during leafy gall ontogenesis was confirmed by RT‐qPCR. Discussion is focused on the potential role of Ntann12 in biotic and abiotic stress responses and in plant development, both processes that may involve Ca2+‐dependent signalling.
The impetus for family‐centred early childhood intervention
Authors: Carpenter B. 
Published: January 2007

AbstractIn this article, the current climate of early intervention is considered, advocating the necessity for it to remain a cutting‐edge service that attends to the changing needs profiles of children and their families.The article reviews the difficulties experienced by families in the UK, where, as the government acknowledges, life chances are still unequal. It emphasises that early interventions can increase the likelihood of the family being able to engage or re‐engage with mainstream societal services, thus reducing the long‐term costs to society.It discusses the past and present UK policy context from 2004, when Sohns reported that the UK was the only country without a national policy of infrastructure in relation to early childhood intervention, until the present when, a raft of legislation is in place acknowledging its importance and the need for priority.Central to many effective early intervention programmes is the goal of establishing shared communication in the infant–key carer dyad, using alternative communication and therapy‐based interventions. The article discusses parent‐inclusive programmes which meet the needs of both parents and children, and receive endorsement from parents.Finally, the article considers evaluation of early childhood services, and the necessity of increasing the centrality of the family in service delivery in order to provide services which are integrated, relevant and efficacious.
Strong below‐ground competition shapes tree regeneration in invasive Cinnamomum verum forests
Authors: KUEFFER CHRISTOPH , SCHUMACHER EVA , FLEISCHMANN KARL , EDWARDS PETER J. , DIETZ HANSJÖRG 
Published: January 2007

Summary

Plant species invading nutrient‐poor ecosystems are likely to have their greatest impact on the native plant community by competing for resources below‐ground. We investigated how root competition by an invasive tree, Cinnamomum verum, affects regeneration in nutrient‐poor tropical secondary forests, in the Seychelles.
We performed three trenching experiments to investigate the effects of severing the root systems of mature trees on the growth of juveniles. These experiments had the following objectives: (i) to compare the responses of native and invasive saplings to release from root competition; (ii) to compare how seedlings (< 50 cm tall) and saplings (> 50 cm tall) of C. verum respond to trenching; and (iii) to compare the response of C. verum seedlings to trenching in forest stands with and without C. verum as the dominant species.
The results indicate that the dense topsoil root mat produced by mature C. verum trees suppresses the growth of young trees, mainly by increasing competition for scarce nutrients. Growth responses to trenching were stronger for seedlings than saplings, and stronger for juveniles of invasive than of native species. We conclude that stands of C. verum exert a strong below‐ground filtering effect on seedling regeneration. This effect is likely to influence secondary forest succession by selectively reducing the establishment of invasive and small‐seeded species.
Because of the bias in invasion biology towards relatively nutrient‐rich, productive ecosystems, few studies have investigated the role of below‐ground resource competition in plant invasions. Our results for an infertile, phosphorus‐poor ecosystem show that root competition by an alien species can exert a strong influence on forest regeneration. We suggest that this mechanism may be of general importance in nutrient‐poor tropical forests invaded by alien tree species.
Dendrosomes: A New Preparation of Isolated Neurosecretory Dendrites
Authors: Row David V. , Morris John F. , Toescu Emil C. 
Published: January 2007

To investigate secretion from dendrites of magnocellular neurosecretory neurons we have developed a preparation of isolated portions of the dendrites analogous to synaptosomes and neurosecretosomes. The dendrites of magnocellular neurons extend into the ventral glial lamina ventral and lateral to the nucleus. The ventral glial lamina is dissected out and gently homogenized to shear off portions of the dendrites. These re‐seal to form granule‐filled, membrane‐bound structures which we refer to as ‘dendrosomes’. Dendrosomes were recovered by differential centrifugation and identified by light and electron microscopy either in unlabelled preparations or by immunocytochemistry.Stimulation of dendrosomes with 56 mM potassium in the presence of tannic acid, which preserves exocytosed granule cores so that they can be visualized electron microscopically, demonstrates that, in response to a depolarizing stimulus, dendrosomes are capable of secreting by exocytosis the neuropeptides oxytocin (OT) and vasopressin (VP) and their co‐packaged neurophysins.
A Comparison of the Effects of Medial Preoptic Electrical Versus Electrochemical Stimulation on Luteinizing Hormone‐Releasing Hormone Neuronal Responsiveness to Norepinephrine
Authors: Hartman Richard D. , Barraclough Charles A. 
Published: January 2007

AbstractRecently, we reported that luteinizing hormone‐releasing hormone (LHRH) neurons of estrogen‐treated, ovariectomized rats have only limited responsiveness to norepinephrine (NE). These conclusions were based upon observations that NE, when infused intracerebroventricularly, produced only minor increases in plasma luteinizing hormone (LH), whereas, similar infusions following preliminary medial preoptic area (MPOA) electrochemical stimulation (ECS) markedly amplified LH secretion. One difficulty with this approach is that ECS produces an irritative lesion and deposits iron within the tissue, whereas, electrical stimulation (ES) does not have such effects. Accordingly, in the present study, we compared the effects of MPOA–ECS versus –ES on LHRH neuronal responsiveness to NE. While equivalent peak LH concentrations occurred within 15 min after MPOA–ECS or –ES, in the ECS group, LH release was sustained, whereas, it abruptly ceased upon termination of ES (at 15 min). The intracerebroventricular pulse infusion of NE at the time of peak LH secretion (30 min) in MPOA–ECS animals markedly amplified LH release. In these animals, plasma LH remained significantly elevated for 75 min before a decline was observed. In contrast, an infusion of NE at the time of maximal LH release in ES rats (16 min) did not augment LH secretion.The second series of studies examined the effects of MPOA infusions of NE in animals receiving preoptic ES. A single infusion of NE 16 min after ES (i.e. one min after termination of ES) did not amplify LH release, but when two NE pulses were given at 5 and 16 min after beginning preoptic ES, peak plasma LH levels were maintained for an additional 30 min before a decline occurred. Pretreatment of rats with a yS‐adrenoreceptor antagonist (propranolol) or a monoamine oxidase inhibitor did not affect peak LH responses obtained after either MPOA–ES alone or combined with two pulses of NE infused into the MPOA at 5 and 16 min. We conclude that following cessation of MPOA–ES, LHRH neurons rapidly lose their responsiveness to NE, whereas, rats which received MPOA–ECS retain such responsiveness possibly due to the stimulative properties of the iron deposited by the ECS. Presumably, for NE to trigger an LH surge requires prior removal of some intrinsic inhibitory control which regulates LHRH neuronal responsiveness to NE.
Preoptic Unit Responses to Microelectrophoresis of Neurotensin and its Antiserum in Female Rats
Authors: Akema Tatsuo , Kimuraf Fukuko 
Published: January 2007

AbstractWe and other investigators have demonstrated the stimulation of luteinizing hormone secretion following the microinjection of neurotensin (NT) into the medial preoptic area in female rats. The present study electrophysiologically examined the action of the peptide in the same brain region. Microelectrophoresis of NT produced either excitation or inhibition in 24% of the medial preoptic neurons tested in oestrogen‐primed and unprimed ovariectomized animals. Effective blockade of NT‐induced excitatory and inhibitor unit responses by means of the simultaneous application of an antiserum to NT (anti‐NT) indicated that they were produced by specific actions of the peptide. In addition, anti‐NT by itself altered the spontaneous firing rate in some NT‐responsive cells. These findings are in accord with the hypothesis that the preoptic area is a site of the action of NT in the female rat.