bluuebunny/crossref_metadata_2025 huggingface dataset:
Injection of glycosylated recombinant simian IL-7 provokes rapid and massive T-cell homing in rhesus macaques
Authors: Beq Stéphanie , Rozlan Sandra , Gautier David , Parker Raphaëlle , Mersseman Véronique , Schilte Clémentine , Assouline Brigitte , Rancé Iann , Lavedan Pascal , Morre Michel , Cheynier Rémi
Published: April 2009

Interleukin-7 (IL-7), the principal cytokine implicated in thymopoiesis and peripheral T-cell homeostasis, is presently under evaluation in human diseases characterized by persistent lymphopenia. Unexpectedly, before the eventual IL-7–driven T-cell expansion, all treated patients showed a profound T-cell depletion 24 hours after injection. The current study uses the rhesus macaque model to investigate the mechanisms involved in this IL-7–induced T-cell depletion. We identify a new critical function of IL-7 that induces massive and rapid T-cell migration from the blood into various organs, including lymph nodes, parts of the intestine, and the skin. This homing process was initiated after the induction of chemokine receptor expression by circulating T cells and the production of corresponding chemokines in target organs. Finally, we demonstrate that the IL-7–induced cell cycling is initiated within these organs before T cells migrate back into the bloodstream, indicating that T-cell homing is required for in vivo IL-7 function.
Activity-Dependent Compartmentalized Regulation of Dendritic Ca2+Signaling in Hippocampal Interneurons
Authors: Topolnik Lisa , Chamberland Simon , Pelletier Joe-Guillaume , Ran Israeli , Lacaille Jean-Claude
Published: April 2009

Activity-dependent regulation of synaptic inputs in neurons is controlled by highly compartmentalized and dynamic dendritic calcium signaling. Among multiple Ca2+mechanisms operating in neuronal dendrites, voltage-sensitive Ca2+channels (VSCCs) represent a major source of Ca2+influx; however, their use-dependent implication, regulation, and function in different types of central neurons remain widely unknown. Using two-photon microscopy to probe Ca2+signaling in dendrites of hippocampal oriens/alveus interneurons, we found that intense synaptic activity or local activation of mGluR5 induced long-lasting potentiation of action potential evoked Ca2+transients. This potentiation of dendritic Ca2+signaling required mGluR5-induced intracellular Ca2+release and PKC activation and was expressed as a selective compartmentalized potentiation of L-type VSCCs. Thus, in addition to mGluR1a-dependent synaptic plasticity, hippocampal interneurons in the feedback inhibitory circuit demonstrate a novel form of mGluR5-induced dendritic plasticity. Given an implication of L-type VSCCs in the induction of Hebbian LTP at interneuron excitatory synapses, their activity-dependent regulation may represent a powerful mechanism for regulating synaptic plasticity.
Connections of the Dorsomedial Visual Area: Pathways for Early Integration of Dorsal and Ventral Streams in Extrastriate Cortex
Authors: Rosa Marcello G. P. , Palmer Susan M. , Gamberini Michela , Burman Kathleen J. , Yu Hsin-Hao , Reser David H. , Bourne James A. , Tweedale Rowan , Galletti Claudio
Published: April 2009

The dorsomedial area (DM), a subdivision of extrastriate cortex characterized by heavy myelination and relative emphasis on peripheral vision, remains the least understood of the main targets of striate cortex (V1) projections in primates. Here we placed retrograde tracer injections encompassing the full extent of this area in marmoset monkeys, and performed quantitative analyses of the numerical strengths and laminar patterns of its afferent connections. We found that feedforward projections from V1 and from the second visual area (V2) account for over half of the inputs to DM, and that the vast majority of the remaining connections come from other topographically organized visual cortices. Extrastriate projections to DM originate in approximately equal proportions from adjacent medial occipitoparietal areas, from the superior temporal motion-sensitive complex centered on the middle temporal area (MT), and from ventral stream-associated areas. Feedback from the posterior parietal cortex and other association areas accounts for <10% of the connections. These results do not support the hypothesis that DM is specifically associated with a medial subcircuit of the dorsal stream, important for visuomotor integration. Instead, they suggest an early-stage visual-processing node capable of contributing across cortical streams, much as V1 and V2 do. Thus, although DM may be important for providing visual inputs for guided body movements (which often depend on information contained in peripheral vision), this area is also likely to participate in other functions that require integration across wide expanses of visual space, such as perception of self-motion and contour completion.
Excitation of Histaminergic Tuberomamillary Neurons by Thyrotropin-Releasing Hormone
Authors: Parmentier Regis , Kolbaev Sergej , Klyuch Boris P. , Vandael David , Lin Jian-Sheng , Selbach Oliver , Haas Helmut L. , Sergeeva Olga A.
Published: April 2009

The histaminergic tuberomamillary nucleus (TMN) controls arousal and attention, and the firing of TMN neurons is state-dependent, active during waking, silent during sleep. Thyrotropin-releasing hormone (TRH) promotes arousal and combats sleepiness associated with narcolepsy. Single-cell reverse-transcription-PCR demonstrated variable expression of the two known TRH receptors in the majority of TMN neurons. TRH increased the firing rate of most (ca 70%) TMN neurons. This excitation was abolished by the TRH receptor antagonist chlordiazepoxide (CDZ; 50 μm). In the presence of tetrodotoxin (TTX), TRH depolarized TMN neurons without obvious change of their input resistance. This effect reversed at the potential typical for nonselective cation channels. The potassium channel blockers barium and cesium did not influence the TRH-induced depolarization. TRH effects were antagonized by inhibitors of the Na+/Ca2+exchanger, KB-R7943 and benzamil. The frequency of GABAergic spontaneous IPSCs was either increased (TTX-insensitive) or decreased [TTX-sensitive spontaneous IPSCs (sIPSCs)] by TRH, indicating a heterogeneous modulation of GABAergic inputs by TRH. Facilitation but not depression of sIPSC frequency by TRH was missing in the presence of the κ-opioid receptor antagonist nor-binaltorphimine. Montirelin (TRH analog, 1 mg/kg, i.p.) induced waking in wild-type mice but not in histidine decarboxylase knock-out mice lacking histamine. Inhibition of histamine synthesis by (S)-α-fluoromethylhistidine blocked the arousal effect of montirelin in wild-type mice. We conclude that direct receptor-mediated excitation of rodent TMN neurons by TRH demands activation of nonselective cation channels as well as electrogenic Na+/Ca2+exchange. Our findings indicate a key role of the brain histamine system in TRH-induced arousal.
Activity Profiles of Cholinergic and Intermingled GABAergic and Putative Glutamatergic Neurons in the Pontomesencephalic Tegmentum of Urethane-Anesthetized Rats
Authors: Boucetta Soufiane , Jones Barbara E.
Published: April 2009

Cholinergic neurons in the pontomesencephalic tegmentum form part of the ascending activating system and are thought to participate in stimulating cortical activation. Yet in the laterodorsal tegmental and pedunculopontine tegmental nuclei (LDT and PPT), they lie intermingled with GABAergic and glutamatergic neurons, which could also modulate cortical activity and sleep–wake state. To characterize the discharge of these cell types in relation to cortical activity, we recorded neurons in urethane-anesthetized rats during spontaneous slow wave and somatosensory evoked fast electroencephalographic (EEG) activity, then labeled the cells by juxtacellular technique with Neurobiotin (Nb) and dual-immunostained them for vesicular acetylcholine transporter (VAChT) and glutamic acid decarboxylase (GAD). All cholinergic cells discharged minimally during prestimulation (∼0.5 Hz) and moderately in a tonic manner (∼4 Hz) during stimulation. Being heterogeneous, some GABAergic, called “On,” cells (∼48%) increased their discharge (from ∼4 to 7 Hz), whereas others, called “Off” cells (∼38%), decreased or ceased firing during stimulation. Similarly, some noncholinergic/non-GABAergic On cells increased (from ∼2 to 6 Hz, ∼49%), whereas other Off cells decreased firing (∼35%) during stimulation. Putative glutamatergic On together with GABAergic On neurons could thus act in parallel with cholinergic cells to stimulate cortical activation. Possibly influenced by cholinergic On and glutamatergic Off cells, whose change in discharge precedes theirs, the GABAergic Off cells could oppose neighboring neurons such as noradrenergic cells, which discharge during waking and cease firing during sleep. By concerted activity, these heterogeneous cell groups can modulate cortical activity and behavioral state across the sleep–waking cycle.
A modern nyelőcsősebészet és a késői funkcionális eredmények “többismeretlenes egyenlete” – MTA Doktori Pályázatr
Authors: Altorjay Áron
Published: April 2009

Absztrakt

Azonos típusú betegségek esetén ugyanolyan műtéti eljárást alkalmazva, anatómiailag ideálisnak mondható per primam sebgyógyulást követően a késői funkcionális eredmények sokszor mégsem azonosak. Ennek hátterét kutatva 637 nyelőcső- és gyomorműtét összesített adatait és a műtétek alatt nyert szövetminták biokémiai, hisztológiai és elektronmikroszkópos feldolgozásával nyert eredményeit értékeltük. Az antirefluxműtétek utáni panaszok egyik lehetséges okaként a refluxos LES izomban hypertrophiára jellemző anyagcsere-változást és enteralis ganglionitist találtunk. A Z-vonal endoscopos klippelésével, majd ezt követően kontrasztanyagos nyelésröntgennel és substractiós képelemzéssel sikerült a rövid oesophagus jelenlétét preoperative igazolni. Megállapítottuk, hogy refluxbetegségben a nyitott műtétre az ezredforduló után is szükség lehet, elsősorban az anamnaesisben szereplő felhasi műtétek, sikertelen nyitott vagy laparoscopos rekonstrukciók, illetve szövődményes reflux eseteiben. A cardia adenocarcinomáiban a daganatot határoló ép szövet és a daganat proteolyticus enzimaktivitásainak – AMAN, CB és DPP I – hányadosa prognosztikus értékkel bír, segítségével a neoadjuváns kemo-radioterápia indikációja felállítható. Az “Akiyama-gyomorban” az operációt követően jelentkező panaszok jól korrelálnak a myoelektromos paraméterekkel és a gyomor contractilis aktivitásával. Az elektromechanikus adaptáció folyamata a műtét utáni tünetek fokozatos regressziójában nyilvánul meg. A gastro-jejuno-duodenalis interpositio (GJDI) egy olyan “second best” műtéti megoldás, mely mind a korai Barrett-carcinomák, mind a pepticus stricturák miatt végzett limitált oesophagus resectiókat követően a jejunalis vagy colon-interpositiók technikai nehézségei estén kerül előtérbe.
Ghrelin suppresses noradrenaline release in the brown adipose tissue of rats
Authors: Mano-Otagiri Asuka , Ohata Hisayuki , Iwasaki-Sekino Azusa , Nemoto Takahiro , Shibasaki Tamotsu
Published: April 2009

To clarify the role of ghrelin in the regulatory mechanism of energy metabolism, we analyzed the effects of centrally and peripherally administered ghrelin on noradrenaline release in the brown adipose tissue (BAT) of rats using a microdialysis system. I.c.v. administration of ghrelin at a dose of 500 pmol suppressed noradrenaline release in BAT, and microinjection of ghrelin (50 pmol) into the paraventricular nucleus (PVN) or arcuate nucleus (ARC) of the hypothalamus also suppressed noradrenaline release in BAT. In addition, i.v. administered ghrelin (30 nmol) suppressed noradrenaline release in BAT, and this suppression was blocked by a vagotomy. Neither i.c.v. nor i.v. administration of des-acyl ghrelin, which does not bind to GH secretagogue receptor type 1a (GHS-R1a), affected noradrenaline release in BAT. These results indicate that ghrelin increases energy storage by suppressing the activity of the sympathetic nerve innervating BAT. It seems that the PVN and ARC, which express GHS-R1a, are the sites of action of ghrelin in the brain and that the action of peripheral ghrelin on the sympathetic nerve activity innervating BAT is mediated by the vagal nerve, which also expresses GHS-R1a.
Modeling Irrigation Management Strategies to Maximize Cotton Lint Yield and Water Use Efficiency
Authors: Baumhardt R. L. , Staggenborg S. A. , Gowda P. H. , Colaizzi P. D. , Howell T. A.
Published: April 2009

Increasing pumping costs and declining well capacities in the Southern High Plains compel producers to seek irrigation strategies to maximize yield and water use efficiency (WUE), which is the ratio of yield to evapotranspiration (ET). Cotton (Gossypium hirsutum L.) is suited to deficit irrigation using wells ranging from 0.29 to 0.93 L s−1 ha−1 capacity to supply limited, 2.5 mm d−1, to complete, 8.1 mm d−1 ET replacement. Our objectives were to (i) evaluate irrigation capacity and duration effects on lint yield, and (ii) compare application strategies that maximize yield and WUE. The simulation model GOSSYM was used with 1959 to 2000 weather records from Bushland, TX, to calculate yields of cotton grown on a Pullman clay loam (fine, mixed, superactive, thermic Torrertic Paleustoll) with 50 or 100% initial available soil water. We compared all combinations of irrigation duration (4, 6, 8, and 10 wk) and capacity (for ET replacement of 2.5, 3.75, and 5.0 mm d−1 and dryland). Simulated lint yield decreased as irrigation decreased; however, yields for similar irrigation totals increased with increasing irrigation capacity. Simulated yields for cotton irrigated > 8 wk did not differ among irrigation capacities, but cotton irrigated at 5.0 mm d−1 maintained yield with earlier irrigation termination at 6 wk. Based on mean yields, we determined that spreading water to deficit irrigate a field with 2.5 mm d−1 yielded ∼5% less lint than concentrating that water to irrigate smaller fields at 3.75 or 5.0 mm d−1 that were averaged with complementary (2:1 and 1:1) dryland areas.
Simulating Switchgrass Growth and Development under Potential and Water‐Limiting Conditions
Authors: Grassini Patricio , Hunt Eric , Mitchell Robert B. , Weiss Albert
Published: April 2009

Anticipating a demand for switchgrass (Panicum virgatum L.) as a source for biofuel production, a crop simulation model of this crop can be a component of a biofuel decision support system. The objective of this effort was to develop and test a model for switchgrass, based on robust empirical relationships between plant behavior and the environment. The model simulates date of annual growth initiation (AGI), anthesis, aboveground biomass, leaf area index (LAI), and water balance components with a daily time step for crops grown under potential and water‐ limiting conditions. Daily weather data (solar radiation, maximum and minimum temperature, and rainfall), soil available water‐holding capacity (AWHC), and the fraction of AWHC at the date of AGI (FAWHC‐AGI) are required inputs. Two cultivar‐specific parameters, the maximum rate of development at the optimum temperature (Rmax) and maximum LAI (MAXLAI), synthesize differences in development and growth between cultivars. Tested against 10 independent data sets, the model generated good predictions of date of anthesis (root mean square error [RMSE] = 3 d) and aboveground biomass (RMSE = 1.5 Mg ha−1).
A Pirandellian Perspective on Suicide
Authors: Elwood Thomas W.
Published: April 2009

Suicide continues to be a major public health problem internationally. Nobel Laureate Luigi Pirandello wrote about the topic of suicide extensively in his various plays, novels, and short stories. This essay draws on these sources to portray the different kinds of unbearable situations in which individuals find themselves and where the only solution perceived to be of any value whatsoever is to commit suicide. Reference is made to the vicissitudes of Pirandello's own life as well as influences from literature and opera that helped to attract him to this topic.

L'antro della bestia originaria acquatatta dentro a ognuno di noi—The Cave of the Primordial Beast Lurking inside Each of Us. (Appelbaum, 1994)
Directed Search, Rationing and Wage Dispersion
Authors: Hori Kenjiro
Published: April 2009

This paper develops a microeconomic model of directed search, where firms are heterogeneous in the number of vacancies advertised, and wages affect workers' choices when both applying for jobs and accepting a job. An aggregate matching function is derived, which incorporates workers' preferences for firms. The aggregate level of matches is shown to be independent of the workers' preferences in the job acceptance stage. When firms' labor demands are heterogeneous, the matching market equilibrium outcome is suboptimal. Matching efficiency is, however, attained in equilibrium, when wages are employed as a rationing device. This results in wage dispersion, despite workers being homogeneous.
Optimism and Bargaining Inefficiency
Authors: Li Duozhe , Wong Yat Fung
Published: April 2009

In a modified version of Rubinstein's bargaining game, two players expect the random arrival of a third party, from whom one of them will receive an interim disagreement payoff in every period until an agreement is finally reached. Each player thinks that his own probability of receiving the disagreement payoff is greater than that assessed by the other player; that is, they are mutually optimistic. We show that when the level of optimism is high and not very durable, equilibrium agreement is delayed until the uncertainty is fully resolved. The efficiency loss caused by such a delay remains substantial when the players are extremely patient.
Large cation model of dissociative reduction of electrochromic WO3−x films
Authors: Hepel Maria , Redmond Haley
Published: April 2009

Studies of dissociative reduction processes of electrochromic WO3−x films were conducted to: (i) evaluate their utility for electroetching and (ii) determine their fundamental mechanistic features to reduce or eliminate their occurrence in normal optical switching and modulation operation of WO3−x films. We have found that while the small intercalating cations stabilize WO3−x structure, the large nonintercalating surfactant cations (Et4N+, CtMe3N+) contribute to the dissociative reduction. While these cations do not affect WO3−x structure of anodically protected films (E > 0.2 V), they cause surface lattice polarization on electron injection to the conduction band of WO3−x at lower electrode potentials, in the absence of intercalating cations. We have found that this process is limited to the surface and no structural damage occurs to the underlying film. The mechanistic aspects of the process have been discussed on the basis of experimental voltammetric and electrochemical quartz crystal nanogravimetric (EQCN) measurements and ab initio quantum mechanical calculations.
Folding by Numbers: Primary Sequence Statistics and Their Use in Studying Protein Folding
Authors: Wathen Brent , Jia Zongchao
Published: April 2009

The exponential growth over the past several decades in the quantity of both primary sequence data available and the number of protein structures determined has provided a wealth of information describing the relationship between protein primary sequence and tertiary structure. This growing repository of data has served as a prime source for statistical analysis, where underlying relationships between patterns of amino acids and protein structure can be uncovered. Here, we survey the main statistical approaches that have been used for identifying patterns within protein sequences, and discuss sequence pattern research as it relates to both secondary and tertiary protein structure. Limitations to statistical analyses are discussed, and a context for their role within the field of protein folding is given. We conclude by describing a novel statistical study of residue patterning in β-strands, which finds that hydrophobic (i,i+2) pairing in β-strands occurs more often than expected at locations near strand termini. Interpretations involving β-sheet nucleation and growth are discussed.
Maize Arabinoxylan Gels as Protein Delivery Matrices
Authors: Berlanga-Reyes Claudia M. , Carvajal-Millán Elizabeth , Lizardi-Mendoza Jaime , Rascón-Chu Agustin , Marquez-Escalante Jorge A. , Martínez-López Ana Luisa
Published: April 2009

The laccase induced gelation of maize bran arabinoxylans at 2.5% (w/v) in the presence of insulin or β-lactoglobulin at 0.1% (w/v) was investigated. Insulin and β-lacto-globulin did not modify either the gel elasticity (9 Pa) or the cross-links content (0.03 and 0.015 mg di- and triferulic acids/mg arabinoxylan, respectively). The protein release capability of the gel was also investigated. The rate of protein release from gels was dependent on the protein molecular weight. The apparent diffusion coefficient was 0.99 × 10-7 and 0.79 × 10-7 cm2/s for insulin (5 kDa) and β-lactoglobulin (18 kDa), respectively. The results suggest that maize bran arabinoxylan gels can be potential candidates for the controlled release of proteins.
Experimental Autoimmune Encephalomyelitis in the Rat
Authors: Mannie Mark , Swanborg Robert H. , Stepaniak Jolie A.
Published: April 2009

There are several diverse rat models of experimental autoimmune encephalomyelitis (EAE) that can be used to investigate the pathogenesis and regulation of autoimmunity against CNS myelin. The disease course of these models ranges from an acute monophasic disease with limited demyelination to a chronic relapsing or chronic progressive course marked by severe demyelination. These models enable the study of encephalitogenic T cells and demyelinating antibody specific for major neuroantigens such as myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG), or proteolipid protein (PLP), among other important CNS autoantigens. Overall, this unit provides an overview of common methods for induction of active and passive EAE, assessment and analysis of clinical disease, preparation and purification of myelin basic protein, and derivation of neuroantigen‐specific rat T cell lines. This unit also provides a brief discussion of the basic characteristics of these models. Curr. Protoc. Immunol. 85:15.2.1‐15.2.15. © 2009 by John Wiley & Sons, Inc.
Bahiagrass
Authors: Altpeter Fredy , Agharkar Mrinalini , Sandhu Sukhpreet
Published: April 2009

Bahiagrass is a commercially important warm‐season forage and turf grass in the southeastern United States and other subtropical regions. Its popularity among ranchers and homeowners is attributed to persistence under drought, infertility, pest and disease pressures, mowing, and grazing. Bahiagrass has apomictic tetraploid and sexual diploid genotypes, both of which have commercially important cultivars. Development of improved cultivars by traditional breeding is limited by the genetic variability within diploid genotypes and the lack of genetic recombination in apomictic bahiagrass. Genetic engineering of bahiagrass is likely to contribute to the development of improved cultivars. Alternative genetic transformation protocols will be described. Apomictic bahiagrass is a preferred target for genetic transformation due to enhanced uniformity of seed‐derived progeny and transgene containment. Genetic transformation of apomictic cultivar “Argentine” has recently been successfully used to confer herbicide resistance, insect resistance, stress tolerance, and improved turf quality. Genetic transformation of bahiagrass is discussed with regard to crop improvement, risk assessment, and risk management.
Black Walnut
Authors: Michler Charles H. , Pijut Paula M. , Meilan Richard , Smagh Gurpreet , Liang Xiaoyu , Woeste Keith E.
Published: April 2009

Black walnut (Juglans nigraL.), an important fine hardwood timber species in the eastern United States, is the subject of tree improvement efforts both by conventional breeding and bioengineering. This species is mostly used in production of fine furniture, paneling, moldings, and cabinetry. Traits such as tree height, trunk diameter, pin knots, and trunk taper can be improved by breeding and selection, but the addition of herbicide resistance, resistance to some diseases, wood color, and control of heartwood formation may more easily be achieved through bioengineering, especially when genes for these traits are not known to exist within the species' germplasm. This contribution describes efforts underway with black walnut breeding as well as initial efforts to insert marker genes through bioengineering. The author's current bioengineering work underway is directed toward achievement of herbicide resistance and reduction of sapwood. Commercial deployment of bioengineered trees in the United States will likely require control of flowering, elimination of marker genes, and scientific tests to determine potential risks. Future work will address these potential regulatory requirements.
Black Locust
Authors: Arrillaga Isabel , Segura Juan , Merkle Scott A.
Published: April 2009

Black locust (Robinia pseudoacaciaL.), a multipurpose nitrogen‐fixing leguminous forest tree, is among the most widely planted tree species in the world. In this review, available protocols for genetic transformation of the species are updated. The review describes both direct andAgrobacterium‐mediated methods for gene transfer using different explants, bacterial strains, and plasmids and selection agents. Regeneration methods and tests of transgene integration are also covered. Although phenotypically normal transgenic black locust plants have been obtained viaAgrobacterium tumefaciens‐mediated transformation, there are few reports describing engineering of the species with genes of potential economic importance. Thus the transformation challenge for the near future in black locust must lie in extending the established protocols to genes of interest such as those related to pathogen and pest resistance, yield improvement, manipulation of wood formation and phytoremediation.
Design of adaptive variable structure controllers for T–S fuzzy time‐delay systems
Authors: Wu Tai‐Zu
Published: April 2009

In this paper, the adaptive variable structure control problem is presented for Takagi–Sugeno (T–S) fuzzy time‐delay systems with uncertainties and external disturbances. The fuzzy sliding surfaces for the T–S fuzzy time‐delay system are proposed by using a Lyapunov function, and we design the adaptive variable structure controllers such that the global T–S fuzzy time‐delay system confined on the fuzzy sliding surfaces is asymptotically stable. One example is given to illustrate the effectiveness of our proposed methods. Copyright © 2009 John Wiley & Sons, Ltd.
Nonvolatile Memory Concepts Based on Resistive Switching in Inorganic Materials
Authors: Mikolajick Thomas , Salinga Martin , Kund Michael , Kever Thorsten
Published: April 2009

Solid state memories play an important role for the electronic systems used in today's information society. The classical approach of charge storage is expected to reach its physical scaling limits very soon. New storage effects are therefore receiving significant interest from industry and academia. In the paper we summarize recent results on resistive switching effects in inorganic materials obtained in the research groups of the authors. We discuss the implications of these results for the suitability of the investigated material systems as well as for the direction of further research.
Atomic Layer Deposition of High‐k Oxides of the Group 4 Metals for Memory Applications
Authors: Niinistö Jaakko , Kukli Kaupo , Heikkilä Mikko , Ritala Mikko , Leskelä Markku
Published: April 2009

This paper reviews several high‐k ALD processes potentially applicable to the production of capacitors, concentrating on very recent developments. A list of the dielectric materials under investigation consists of the oxides of several metals, including the Group 4 (Ti, Zr, Hf) elements. The binary oxides of Group 4 metals, as well as their mixtures with other oxides, doped hosts, or multi‐layers in the form of nano‐laminates are of interest.Several examples of our recent results are shown, including possible ALD routes to materials not previously grown, as well as advances in process development.
Giant Electric Field Tuning of Magnetic Properties in Multiferroic Ferrite/Ferroelectric Heterostructures
Authors: Liu Ming , Obi Ogheneyunume , Lou Jing , Chen Yajie , Cai Zhuhua , Stoute Stephen , Espanol Mary , Lew Magnum , Situ Xiaodan , Ziemer Kate S. , Harris Vince G. , Sun Nian X.
Published: April 2009

Multiferroic heterostructures of Fe3O4/PZT (lead zirconium titanate), Fe3O4/PMN‐PT (lead magnesium niobate‐lead titanate) and Fe3O4/PZN‐PT (lead zinc niobate‐lead titanate) are prepared by spin‐spray depositing Fe3O4 ferrite film on ferroelectric PZT, PMN‐PT and PZN‐PT substrates at a low temperature of 90 °C. Strong magnetoelectric coupling (ME) and giant microwave tunability are demonstrated by a electrostatic field induced magnetic anisotropic field change in these heterostructures. A high electrostatically tunable ferromagnetic resonance (FMR) field shift up to 600 Oe, corresponding to a large microwave ME coefficient of 67 Oe cm kV−1, is observed in Fe3O4/PMN‐PT heterostructures. A record‐high electrostatically tunable FMR field range of 860 Oe with a linewidth of 330–380 Oe is demonstrated in Fe3O4/PZN‐PT heterostructure, corresponding to a ME coefficient of 108 Oe cm kV−1. Static ME interaction is also investigated and a maximum electric field induced squareness ratio change of 40% is observed in Fe3O4/PZN‐PT. In addition, a new concept that the external magnetic orientation and the electric field cooperate to determine microwave magnetic tunability is brought forth to significantly enhance the microwave tunable range up to 1000 Oe. These low temperature synthesized multiferroic heterostructures exhibiting giant electrostatically induced tunable magnetic resonance field at microwave frequencies provide great opportunities for electrostatically tunable microwave multiferroic devices.
Cluster of presumed organic dust toxic syndrome cases among urban landscape workers—Colorado, 2007
Authors: Boehmer Tegan K. , Jones Taylor S. , Ghosh Tista S. , McCammon Charles S. , Vogt Richard L.
Published: April 2009

Background

Organic dust toxic syndrome (ODTS) is an influenza‐like illness typically affecting agricultural workers exposed to organic dusts. In July 2007, Tri‐County Health Department investigated a cluster of acute respiratory illnesses among urban landscape workers with known mulch exposure.

Methods

An epidemiologic study of landscape workers was conducted. Employees were interviewed regarding illness and occupational exposures. Medical records were reviewed. Mulch samples were tested for fungi and endotoxins.

Results

Five (12%) of 43 employees experienced respiratory illness compatible with ODTS. Illness was associated with prolonged mulch exposure (≥6 vs. <6 hr/day; relative risk = 24.7; 95% confidence interval = 3.3–184.9). Mulch samples contained high levels of Aspergillus spores and endotoxin.

Conclusions

Contaminated mulch was implicated as the source of presumed ODTS among landscape workers, highlighting that ODTS is not limited to rural agricultural settings. Education of employers, safety officers, and clinicians is necessary to improve recognition and prevention of ODTS within urban occupational groups. Am. J. Ind. Med. 52:534–538, 2009. © 2009 Wiley‐Liss, Inc.
Age estimation of archaeological remains using amino acid racemization in dental enamel: A comparison of morphological, biochemical, and known ages‐at‐death
Authors: Griffin R.C. , Chamberlain A.T. , Hotz G. , Penkman K.E.H. , Collins M.J.
Published: April 2009

The poor accuracy of most current methods for estimating age‐at‐death in adult human skeletal remains is among the key problems facing palaeodemography. In forensic science, this problem has been solved for unburnt remains by the development of a chemical method for age estimation, using amino acid racemization in collagen extracted from dentine. Previous application of racemization methods to archaeological material has proven problematic. This study presents the application to archaeological human remains of a new age estimation method utilizing amino acid racemization in a potentially closed system—the dental enamel. The amino acid composition and extent of racemization in enamel from two Medieval cemeteries (Newcastle Blackgate and Grantham, England) and from a documented age‐at‐death sample from a 19th century cemetery (Spitalfriedhof St Johann, Switzerland) were determined. Alterations in the amino acid composition were detected in all populations, indicating that diagenetic change had taken place. However, in the Medieval populations, these changes did not appear to have substantially affected the relationship between racemization and age‐at‐death, with a strong relationship being retained between aspartic acid racemization and the morphological age estimates. In contrast, there was a poor relationship between racemization and age in the post‐medieval documented age‐at‐death population from Switzerland. This appears to be due to leaching of amino acids post‐mortem, indicating that enamel is not functioning as a perfectly closed system. Isolation of amino acids from a fraction of enamel which is less susceptible to leaching may improve the success of amino acid racemization for archaeological age estimation. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.
Age estimation from stages of union of the vertebral epiphyses of the ribs
Authors: Ríos Luis , Cardoso Hugo F.V.
Published: April 2009

This study attempts to fill a persistent gap in the literature by documenting the timing of epiphyseal union at the vertebral end of the ribs in a sample of modern Portuguese skeletons. The skeletal remains of 53 females and 45 males, between the ages of 11 and 30, were taken from the Lisbon documented skeletal collection. Individuals in the sample have been previously described as being representative of a middle‐to‐low socioeconomic segment of the early 20th century Lisbon population. Three anatomical locations were examined for epiphyseal union: the head, the articular tubercle and the nonarticular tubercle. The first epiphysis to show partial union is that of the nonarticular tubercle (females, 11–19 years; males, 11–19 years), followed by the epiphysis of the articular tubercle (females, 11–20 years; males, 16–20 years), and finally by the head epiphysis (females, 15–24 years; males, 16–22 years), which can still show incomplete epiphyseal closure at 25 and 24 years for females and males, respectively. A trend for earlier female maturation was observed, but the statistical tests only confirmed this result for some ribs and age groups. No directional asymmetry was found, but a significant fluctuating asymmetry was observed in all three epiphyses. A preliminary analysis showed that the asymmetric group of individuals in the study sample includes all the rural‐to‐urban migrants, relative to the symmetric group. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.
Asymmetric transfer hydrogenation catalyzed by a novel planar chiral N‐heterocyclic carbene–rhodium(I) complex
Authors: Jiang Ru , Sun Xiaoli , He Wei , Chen Hui , Kuang Yongqing
Published: April 2009

A novel chelated ferrocene‐based planar chiral N‐heterocyclic carbene‐Rh(I) complex was synthesized by a simple method. It was applied to the asymmetric transfer hydrogenation of prochiral ketones. Enantioselectivities of up to 67% ee were observed. Copyright © 2009 John Wiley & Sons, Ltd.
Self‐assembly and drug delivery behaviors of thermo‐sensitive poly(t‐butyl acrylate)‐b‐poly(N‐isopropylacrylamide) micelles
Authors: Li Guiying , Guo Lei , Ma Songmei
Published: April 2009

Self‐assembly of thermo‐sensitive poly (t‐butyl acrylate)‐b‐poly(N‐isopropylacrylamide) (PtBA‐ b‐PNIPAM) micelles in aqueous medium and its applications in controlled release of hydrophobic drugs were described. PtBA‐b‐PNIPAM was synthesized by atom transfer radical polymerization and aggregated into thermo‐sensitive core‐shell micelles with regular spheres in water, which was confirmed by 1H‐NMR, fluorescence spectroscopy, transmission electron microscopic (TEM), and UV–vis spectroscopic techniques. The critical micelle concentration of micelles decreased with the increase of the hydrophobic components. The anti‐inflammation drug naproxen (NAP) was loaded as the model drug into polymeric micelles, which showed a dramatic thermo‐sensitive fast/slow switching behavior around the lower critical solution temperature (LCST). When the temperature was enhanced above LCST, release of NAP from core‐shell micelles was accelerated ascribed to the temperature‐induced deformation of micelles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Sequential designs for ordinal phase I clinical trials
Authors: Liu Guohui , Rosenberger William F. , Haines Linda M.
Published: April 2009

Sequential designs for phase I clinical trials which incorporate maximum likelihood estimates (MLE) as data accrue are inherently problematic because of limited data for estimation early on. We address this problem for small phase I clinical trials with ordinal responses. In particular, we explore the problem of the nonexistence of the MLE of the logistic parameters under a proportional odds model with one predictor. We incorporate the probability of an undetermined MLE as a restriction, as well as ethical considerations, into a proposed sequential optimal approach, which consists of a start‐up design, a follow‐on design and a sequential dose‐finding design. Comparisons with nonparametric sequential designs are also performed based on simulation studies with parameters drawn from a real data set.
High‐dimensional data analysis: Selection of variables, data compression and graphics – Application to gene expression
Authors: Läuter Jürgen , Horn Friedemann , Rosołowski Maciej , Glimm Ekkehard
Published: April 2009

The paper presents effective and mathematically exact procedures for selection of variables which are applicable in cases with a very high dimension as, for example, in gene expression analysis. Choosing sets of variables is an important method to increase the power of the statistical conclusions and to facilitate the biological interpretation. For the construction of sets, each single variable is considered as the centre of potential sets of variables. Testing for significance is carried out by means of the Westfall‐Young principle based on resampling or by the parametric method of spherical tests. The particular requirements for statistical stability are taken into account; each kind of overfitting is avoided. Thus, high power is attained and the familywise type I error can be kept in spite of the large dimension. To obtain graphical representations by heat maps and curves, a specific data compression technique is applied. Gene expression data from B‐cell lymphoma patients serve for the demonstration of the procedures.
Adaptive patient enrichment designs in therapeutic trials
Authors: Wang Sue‐Jane , James Hung H. M. , O'Neill Robert T.
Published: April 2009

The utility of clinical trial designs with adaptive patient enrichment is investigated in an adequate and well‐controlled trial setting. The overall treatment effect is the weighted average of the treatment effects in the mutually exclusive subsets of the originally intended entire study population. The adaptive enrichment approaches permit assessment of treatment effect that may be applicable to specific nested patient (sub)sets due to heterogeneous patient characteristics and/or differential response to treatment, e.g. a responsive patient subset versus a lack of beneficial patient subset, in all patient (sub)sets studied. The adaptive enrichment approaches considered include three adaptive design scenarios: (i) total sample size fixed and with futility stopping, (ii) sample size adaptation and futility stopping, and (iii) sample size adaptation without futility stopping. We show that regardless of whether the treatment effect eventually assessed is applicable to the originally studied patient population or only to the nested patient subsets; it is possible to devise an adaptive enrichment approach that statistically outperforms one‐size‐fits‐all fixed design approach and the fixed design with a pre‐specified multiple test procedure. We emphasize the need of additional studies to replicate the finding of a treatment effect in an enriched patient subset. The replication studies are likely to need fewer number of patients because of an identified treatment effect size that is larger than the diluted overall effect size. The adaptive designs, when applicable, are along the line of efficiency consideration in a drug development program.
Prediction of posthepatectomy hepatic functional reserve by serum hyaluronate
Authors: Yachida S , Wakabayashi H , Okano K , Suzuki Y
Published: April 2009

Background

Serum hyaluronate can be used as an index of hepatic sinusoidal endothelial cell function and hepatic fibrosis. This study was designed to clarify the clinical significance of the serum hyaluronate level as a parameter of functional reserve.

Methods

The study included 283 patients undergoing hepatectomy. Liver function parameters were examined before surgery and compared with outcomes. Patients were retrospectively grouped according to the presence or absence of postoperative hepatic dysfunction.

Results

Preoperative serum hyaluronate levels were significantly raised in parallel with the degree of severity of the underlying chronic liver disease. Regression analysis revealed serum hyaluronate level to be an independent predictor of portal hypertension. In 131 patients undergoing major hepatectomy, preoperative hyaluronate levels were significantly higher in patients with poor outcome. Multivariable logistic regression analysis demonstrated serum hyaluronate and total bilirubin levels to be independent variables associated with postoperative hepatic dysfunction. Patients with high indocyanine green retention rate at 15 min (over 15 per cent) showed significantly higher morbidity and mortality rates when their serum hyaluronate levels were over 180 ng/ml.

Conclusion

Serum hyaluronate is a simple clinical marker for portal venous pressure and a reliable auxiliary parameter of hepatic functional reserve in combination with other liver function tests.
Outcomes for case-matched laparoscopically assisted versus open restorative proctocolectomy
Authors: El-Gazzaz G S , Kiran R P , Remzi F H , Hull T L , Geisler D P
Published: April 2009

Background

The aim of this study was to compare safety, early and late outcomes, quality of life and functional results of laparoscopically assisted versus open ileal pouch–anal anastomosis (IPAA).

Methods

Patients who had laparoscopically assisted IPAA between 1992 and 2007 were identified from a database and retrospectively matched for age, sex, body mass index (BMI) and operation date to patients who had open IPAA at a ratio of 1 : 2. Intraoperative, postoperative and long-term functional outcomes were compared. Quality of life was determined by the Cleveland Global Quality of Life scale at 1 and 5 years.

Results

A total of 119 patients (59 men, 60 women; mean(s.d) age 35·5(14·2) years, BMI 24·7(5·0) kg/m2) had laparoscopically assisted IPAA, with conversion in nine patients (7·6 per cent); these were compared with 238 patients who had open IPAA. The 30-day and long-term results were similar, as well as quality of life at 1 and 5 years, except that patients in the laparoscopic group had shorter median time to stoma action (2 versus 3 days; P = 0·001) and marginally shorter hospital stay. Median operating times were longer in the laparoscopic group (272 versus 163 min; P = 0·040).

Conclusion

Laparoscopically assisted IPAA had similar outcomes to open IPAA, but with some short-term advantages.
Prognostic impact of para-aortic lymph node micrometastasis in patients with regional node-positive biliary cancer
Authors: Yonemori A , Kondo S , Matsuno Y , Ito T , Tanaka E , Hirano S
Published: April 2009

Background

The presence of para-aortic lymph node metastasis in biliary cancer has a negative impact on prognosis. The relevance of para-aortic lymph node micrometastasis is unknown.

Methods

A total of 546 para-aortic lymph nodes from 49 patients with biliary cancer with positive regional nodes and negative para-aortic nodes were immunostained with epithelial marker CAM5·2 (specific for cytokeratins 7 and 8). Immunostained tumour foci were classified as micrometastases or isolated tumour cells (ITCs) according to their size (larger or smaller than 0·2 mm).

Results

CAM5·2-positive occult carcinoma cells in para-aortic lymph nodes were detected in nine (18 per cent) of 49 patients and in 18 (3·3 per cent) of 546 para-aortic nodes. There was no difference in postoperative survival between patients with and without CAM5·2-positive para-aortic nodes (P = 0·978), but survival for five patients with micrometastases was significantly worse than that for four patients with only ITCs (P = 0·047).

Conclusion

In patients with regional node-positive and para-aortic node-negative biliary cancer, and occult cancer cells in para-aortic lymph nodes, prognosis was significantly worse in those with micrometastases than in patients with only ITCs. An efficient method of intraoperative detection of para-aortic lymph node micrometastases larger than 0·2 mm is needed.
Prolonged survival after hepatic artery embolization in patients with midgut carcinoid syndrome
Authors: Swärd C , Johanson V , Nieveen van Dijkum E , Jansson S , Nilsson O , Wängberg B , Ahlman H , Kölby L
Published: April 2009

Background

Hepatic artery embolization (HAE) is a palliative treatment for patients with liver metastases from neuroendocrine tumours. HAE reduces hormonal symptoms, but its impact on survival has been questioned.

Methods

Biochemical responses and survival in consecutive patients with disseminated liver metastases from midgut carcinoid tumours were studied after HAE. Repeat HAE was performed in selected patients with radiological and biochemical signs of progression.

Results

Of 107 patients who had HAE, the median survival from the first procedure was 56 (range 1–204) months. Prolonged survival showed a strong correlation with reduction of urinary 5-hydroxyindoleacetic acid (P = 0·003) and plasma chromogranin A (P = 0·001) levels. The biochemical response to repeat HAE was similar to that for the first procedure (P = 0·002). The complication rate was low (7·5 per cent), as was the mortality rate (1·9 per cent) within 1 month of HAE.

Conclusion

HAE is safe, provides good control of hormonal symptoms, and prolongs survival in biochemically responsive patients. It is a valuable palliative option for patients with midgut carcinoid syndrome due to liver metastases and can be repeated in patients with a favourable response to the first procedure.
Simultaneous determination of acyclovir, ganciclovir, and (R)‐9‐[4‐hydroxy‐2‐(hydroxymethyl)butyl]guanine in human plasma using high‐performance liquid chromatography
Authors: Weller Dennis R. , Balfour Henry H. , Vezina Heather E.
Published: April 2009

Acyclovir, ganciclovir and (R)‐9‐[4‐hydroxy‐2‐(hydroxymethyl)butyl]guanine are active in vitro against the Epstein–Barr virus (EBV) but their in vivo anti‐EBV activity is not well understood. We developed a novel, sensitive high‐performance liquid chromatography assay with ultraviolet detection for measuring acyclovir, ganciclovir and (R)‐9‐[4‐hydroxy‐2‐(hydroxymethyl)butyl]guanine in human plasma to identify quantitative relationships between in vitro anti‐EBV activity and therapeutic response. Characteristics of the assay include a low plasma volume (200 µL), perchloric acid protein precipitation, use of penciclovir as the internal standard, run times less than 8 min and a 50 ng/mL lower limit of quantification. The within‐ and between‐assay variability is 0.7–4.8 and 1.0–7.9%, respectively. Accuracy for all three drugs ranges from 89.5 to 106.4% for four quality controls (50, 100, 1000 and 10,000 ng/mL). This assay supports pharmacokinetic and pharmacodynamic studies of candidate anti‐EBV drugs in children and adults with EBV infections. Copyright © 2009 John Wiley & Sons, Ltd.