bluuebunny/crossref_metadata_2025_split huggingface dataset:
Homeostatic proliferation of naïve CD8+ T cells depends on CD62L/L‐selectin‐mediated homing to peripheral LN
Authors: Schuster Kerstin , Gadiot Jules , Andreesen Reinhard , Mackensen Andreas , Gajewski Thomas F. , Blank Christian 
Published: August 2009

AbstractAdoptive transfer of naïve CD8+ T cells into lymphopenic recipients results both in spontaneous proliferation and in partial activation of T cells, a phenomenon termed homeostatic proliferation (HP). HP of CD8+ T cells is dependent on host IL‐7, IL‐15, and MHC‐class I and has been shown to prevent T‐cell tolerance, reverse T‐cell anergy and support T‐cell‐mediated tumor control in vivo. However, the initial anatomic site of HP is still under debate. Since we observed that the earliest detectable HP occurs within LN and that T cells undergoing HP retain a CD62Lbright phenotype, we investigated the functional role of CD62L for this process. We found that CD62L‐expression on T cells is required for optimal HP and HP was impaired in lymphotoxin‐αβ−/− mice, indicating the necessity for intact host secondary lymphoid organ structures. Use of the LN egression inhibitor FTY720 indicated that LN structures were pivotal to yield homeostatically proliferated T cells detected in other compartments. Consistent with these results, HP‐supported control of MC57‐SIY tumors depended on CD62L. Our data indicate a critical role for CD62L and LN homing for the process of HP, which has implications for adoptive immunotherapy approaches of cancer.
Multiple functions of human T cells generated by experimental malaria challenge
Authors: Todryk Stephen M. , Walther Michael , Bejon Philip , Hutchings Claire , Thompson Fiona M. , Urban Britta C. , Porter David W. , Hill Adrian V. S. 
Published: August 2009

AbstractProtective immunity generated following malaria infection may be comprised of Ab or T cells against malaria Ag of different stages; however, the short‐lived immunity that is observed suggests deficiency in immune memory or regulatory activity. In this study, cellular immune responses were investigated in individuals receiving Plasmodium falciparum sporozoite challenge by the natural (mosquito bite) route as part of a malaria vaccine efficacy trial. Parasitemia, monitored by blood film microscopy and PCR, was subsequently cleared with drugs. All individuals demonstrated stable IFN‐γ, IL‐2 and IL‐4 ex vivo ELISPOT effector responses against P. falciparum‐infected RBC (iRBC) Ag, 28 and 90 days after challenge. However, infected RBC‐specific central memory responses, as measured by IFN‐γ cultured ELISPOT, were low and unstable over time, despite CD4+ T cells being highly proliferative by CFSE dilution, and showed an inverse relationship to parasite density. In support of the observation of poor memory, co‐culture experiments showed reduced responses to common recall Ag, indicating malaria‐specific regulatory activity. This activity could not be accounted for by the expression of IL‐10, TGF‐β, FOXP3 or CTLA‐4, but proliferating T cells expressed high levels of CD95, indicating a pro‐apoptotic phenotype. Lastly, there was an inverse relationship between FOXP3 expression, when measured 10 days after challenge, and ex vivo IFN‐γ measured more than 100 days later. This study shows that malaria infection elicits specific Th1 and Th2 effector cells, but concomitant weak central memory and regulatory activity, which may help to explain the short‐lived immunity observed.
A Simple Fluorescent Ion‐Pair Binding Host that Acts as an “If‐Then” Logic Gate
Authors: Dickson Sara Jane , Swinburne Adam N. , Paterson Martin J. , Lloyd Gareth O. , Beeby Andrew , Steed Jonathan W. 
Published: August 2009

AbstractA donor‐acceptor‐type carbazole pyridine derivative behaves as an “if‐then” fluorescent molecular logic gate using chemical inputs in the form of copper(II) cations and nitrate anions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Protonic–Hydridic Bifunctionality: The Protonic (2‐Aminoethyl)dimethylphosphane Ligand in Nitrosyl Tungsten Hydride Complexes
Authors: Chen Zilu , Timokhin Ivan , Schmalle Helmut W. , Fox Thomas , Blacque Olivier , Berke Heinz 
Published: August 2009

AbstractThe chemistry of nitrosyl tungsten hydrides bearing the (2‐aminoethyl)dimethylphosphane ligand (edmp) with an acidic NH functionality was studied. Such complexes were targeted by applying the reaction of WCl3(NO)(CH3CN)2 with edmp, which gave [WCl2(NO)(η2‐edmp)2][Cl] (1a) and [WCl2(NO)(η2‐edmp)2][BPh4] (1b). Complex 1b was treated with Zn to produce [W(H)(Cl)(NO)(η2‐edmp)2][BPh4] (2b). Subsequent attempts with the use of WCl(NO)[P(OMe)3]4 and edmp as starting materials produced {W(NO)(η2‐edmp)2[P(OMe)3]}[Cl] (3a) at 85 °C and [W(H)(Cl)(NO)(η2‐edmp)2][Cl] (2a) at 120 °C. Substitution of the P(OMe)3 ligand in {W(η2‐edmp)2(NO)[P(OMe)3]}[BPh4] (3b) with CO afforded [W(CO)(η2‐edmp)2(NO)][BPh4] (4b). Complex 4b was treated withNaHBEt3, resulting in a dihydride product [W(CO)trans‐(η1‐edmp)2(H)2(NO)]Na (4c). The chlorido complexes containing one η2‐edmp ligand WCl(NO)(η2‐edmp)(PMe3)2 (5a), WCl(NO)(η2‐edmp)(CO)(PMe3) (6a), WCl(NO)(η2‐edmp)[P(OMe)3]2 (5b), and WCl(NO)(CO)(η2‐edmp)[P(OMe)3] (6b) were prepared and treated with NaHBEt3 to obtain the corresponding hydride species WH(NO)(η2‐edmp)[P(OMe)3]2 (8b), WH(NO)(CO)(η2‐edmp)(PMe3) (7a), and WH(NO)(CO)(η2‐edmp)[P(OMe)3] (7b). The initially formed WH(NO)(η2‐edmp)(PMe3)2 (8a) was spontaneously transformed into the amide complex W(NO)(CO)(NHCH2CH2PMe2)(PMe3) (11a) with loss of H2. The anionic dihydride products [W(H)2(η1‐edmp)(NO)L2]Na [L = PMe3 (9a) and L = PMe3 (9b)] were produced from 7a and 7b by the reaction with NaHBEt3. Hydride 8b turned out to be the most stable hydride complex in the given series. NMR spectroscopic experiments and deuterium labeling showed that 8b coexists in equilibrium with corresponding dihydrogen amide complex 10b. The structures of compounds 1a, 2b, 3a, 4b, 5b, 6a, and 6b were studied by single‐crystal X‐ray diffraction.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Thermally Pretreated 46% Pt/Vulcan XC72: Characterisation by TGA/DSC/TEM and Cyclic Voltammetry
Authors: Pinchuk O. A. , Aubuchon S. R. , Marks C. , Dominey R. , Dundar F. , Deniz O. F. , Ata A. , Wynne K. J. 
Published: August 2009

AbstractWe report a study of thermal stability and impact of thermal pretreatment procedures for 46% Pt/Vulcan XC72 (Tanaka) fuel cell catalyst. Stability in air and in inert gas (nitrogen, argon, helium) has been investigated by thermal gravimetric analysis (TGA), TGA‐mass spectrometry (TGA‐MS) and differential scanning calorimetry (DSC). Two distinct low temperature mass loss processes (100–200 and 285–300 °C) were observed, each exhibiting unique pretreatment temperature dependencies. TGA‐MS data in helium show fragment ions that suggest the thermal degradation processes are associated with decomposition of materials such as processing aids. Transmission electron microscopy (TEM) reveals a modest increase in average Pt nanoparticle size upon thermal pretreatment. After a pretreatment protocol based on TEM and thermal characterisation (300 °C/15 min, N2), the electrochemically active surface area did not increase. At the kinetically controlled potential region (E >0.8 V) there was a small drop in current density for treated 46% Pt/C in comparison with as‐received catalyst. The slowing in ORR kinetics is significant. Apparently, the removal of organic components, which would improve mass transport, is negated by increased nanoparticle size.
Design approach for the hybrid underground station at Union Suare/Market Street in San Francisco
Authors: Marcher Thomas , Aydogmus Taner , John Max , Fowler Matthew E. 
Published: August 2009

AbstractThe new Central Subway extension through downtown San Francisco consists of three underground stations and 2.7 km TBMdriven twin tunnel. This paper provides a description of the preliminary analyses and design of the ground support and final lining for the Union Square\Market Street Station (UMS) along Stockton Street. This station will serve the Union Square Shopping District and connect to the BART Powell Street Station. Due to shortage of space above ground and to minimize surface disruption, the UMS station design requires a complex hybrid method consisting of a 20 m deep braced cut‐and‐cover box with a mined enlargement bulb below it with a height of 9.3 m and a width of 17.8 m.The majority of the UMS station will be excavated in saturated alluvial deposits. Undifferentiated old bay deposits will be encountered in the invert, underlain by dense marine sands. The groundwater varies from 5 to 10 m below ground level, so uplift of the combined bulb/box structure has to be taken into account.The Finite Element (FE) analysis of the UMS station cavern reflects the separate construction phases of the station platform box and the bulb to account for soil‐structure interaction and load‐sharing effects. FE analyses are used to estimate support requirements including ground improvement and to predict surface settlements.Die Erweiterung der Central Subway durch die Innenstadt von San Francisco beinhaltet drei Stationsbauwerke und 2,7 km maschinell vorgetriebene Doppelröhrentunnel. In diesem Artikel erfolgt eine Beschreibung der Voruntersuchungen und Vorbemessung der Stützmaßnahmen sowie der Innenschale der Union Square\Market Street Station (UMS) im Verlauf der Stockton Street. Diese Station soll dem Union Square Shopping Distrikt dienen und zur BART Powell Street Station verbinden.Aufgrund der beengten Platzverhältnisse und zur Minimierung der Beeinträchtigung der Oberfläche ist ein “hybrides” Konzept der UMS‐Station erforderlich. Dieses besteht aus einer 20 m tiefen ausgesteiften Baugrube (Box) und einer darunterliegenden bergmännisch hergestellten Kaverne (Bulb) mit 9,3 m Höhe und 17,8 m Breite.Der Großteil der UMS‐Station befindet sich in gesättigten alluvialen Ablagerungen. Undifferenziert werden alte Bucht‐Ablagerungen und dichte marine Sande in der Sohle vorgefunden. Der Grundwasserspiegel variiert in einer Teufe zwischen 5 bis 10 m unter der Oberfläche, aus diesem Grund ist der Auftrieb des kombinierten Bauwerks bestehend aus Bulb und Box zu berücksichtigen.In Finite Element (FE) Berechnungen der UMS‐Station werden die einzelnen Bauphasen des Stationsbauwerks, sowohl von Box als auch Bulb, modelliert, um die Wechselwirkungen von Baugrund‐Bauwerk und die jeweiligen Lastumlagerungen zu berücksichtigen. Mittels FE‐Berechnungen werden schließlich die notwendigen Stützmaßnahmen – diese beinhalten auch Bodenverbesserungsmaßnahmen – und die Oberflächensetzungen festgelegt.
Structural design of tunnels – how reliable are the results of numerical calculations? Investigation using a 3D model for a mined underground railway station
Authors: Walter Herbert 
Published: August 2009

AbstractState‐of‐the‐art material laws in numerical models make it possible to integrate the structural design and the ultimate limit state analysis into the numerical model (“Implicit design”). The material laws limit the stresses to values, which the material can bear. Partial factors of safety on the load and resistance sides can also be taken into account. Using the example of a time‐independent, 3D mathematical model for an underground railway station with tunnel junctions, which is being constructed by mining in soft soil, this paper investigates to what extent the material laws and the mathematical model fulfill the requirements laid down in the Eurocode for ultimate limit state analysis and how near these results are to the real situation.Some simplifications and weaknesses of the mathematical model are explained, their effect on the results investigated and evaluated in relation to the uncertainties in the characteristics available for materials. Suggestions are made as to how the effects of defects in the model in an unsafe direction can be avoided. Further aspects, which can affect the reliability of calculations, are also pointed out.Hochwertige Stoffgesetze in Berechnungsmodellen erlauben es, die Bemessung und den Tragsicherheitsnachweis in das numerische Modell zu integrieren (“Implizite Bemessung”): Die Stoffgesetze begrenzen die Spannungen auf Werte, die das Material ertragen kann. Auch Teilsicherheitsbeiwerte auf Last‐ und Widerstandsseite können erfasst werden. Am Beispiel des zeitabhängigen, räumlichen Rechenmodells für eine U‐Bahnstation mit Tunnelverschneidungen, die in bergmännischer Bauweise im Lockergestein hergestellt wird, wird untersucht, wie weit die Stoffgesetze und das Rechenmodell die in den Eurocodes festgelegten Anforderungen zum Nachweis der Tragsicherheit erfüllen und wie realitätsnah die Berechnungsergebnisse sind.Es werden einige Vereinfachungen und Schwächen des Rechenmodells beleuchtet, ihre Auswirkungen auf das Ergebnis untersucht und in Relation zu den Unsicherheiten bei den zur Verfügung stehenden Materialkennwerten bewertet. Vorschläge werden unterbreitet, wie Auswirkungen von Modellfehlern auf der unsicheren Seite vermieden werden können. Auf weitere Aspekte, die die Zuverlässigkeit von Berechnungen beeinträchtigen können, wird ebenfalls hingewiesen.
Combining microwave and ultrasound irradiation for rapid synthesis of nanowires: a case study on Pb(OH)Br
Authors: Shen Xiao‐Fang 
Published: August 2009

AbstractBACKGROUND: One‐dimensional (1D) nanostructures such as wires, tubes and belts have attracted much attention in recent years because of their fascinating properties and promising applications, and various methods have been developed to prepare 1D nanostructures. Microwave and ultrasound, two methodologies for rapid synthesis, have both been applied to fabricate nanostructures. This paper reports on combining microwave and ultrasound irradiation as a new strategy for rapid synthesis of nanowires. Using Pb(OH)Br as a study case, nanowires were rapidly synthesized under the combined irradiation. The use of the ionic liquid 1‐butyl‐3‐methylimidazolium bromide as a structure‐directing agent and microwave absorbent significantly simplified the preparation procedure.RESULTS: Combined microwave–ultrasound irradiation at (50 W–50 W) greatly reduced the reaction time (10 min) and significantly increased the product yield (45.0%) in comparison with conventional heating (24 h reaction time, 23.0% yield). Combined microwave–ultrasound irradiation at (50 W–50 W) also changed the resultant wires from 20–30 µm diameter and 2–3 mm long to 80–800 nm and 50–100 µm, respectively. Further increase in power of the combined irradiation (250 W–50 W) led to a dramatic reduction in the reaction time (80 s) with a slightly increased yield of 48.2%.CONCLUSIONS: The obvious advantages of combined microwave–ultrasound irradiation are marked improvement of the product yield, significant enhancement of reaction rate and increased aspect ratio of the 1D structure. Copyright © 2009 Society of Chemical Industry
Role of MMP9 on invadopodia formation in cells from adenoid cystic carcinoma. Study by laser scanning confocal microscopy
Authors: Nascimento Camila F. , Gama‐De‐Souza Letícia N. , Freitas Vanessa M. , Jaeger Ruy G. 
Published: August 2009

AbstractMigration, invasion and protease activity are essential for tumor progression and metastasis. Metastatic cells rely on invadopodia to degrade and invade extracellular matrix (ECM). Invadopodia are membrane protrusions with enzymes required for ECM degradation. These protrusions contain cortactin and membrane type 1 matrix metalloproteinase (MT1‐MMP) superimposed to areas of digested matrix. Here we characterized invadopodia in a cell line (CAC2) derived from human adenoid cystic carcinoma. We carried out fluorescent‐substrate degradation assay to assess in situ protease activity of CAC2 cells. Digestion spots in fluorescent substrate appear as black areas in green background. Cells were cultured on Matrigel‐gelatin‐FITC and fixed after 1 h and 3 h. CAC2 cells were double labeled to actin and cortactin. Cells were also double stained to actin and MT1‐MMP. Samples were studied by laser scanning confocal microscopy. In all time points CAC2 cells showed actin, cortactin, and MT1‐MMP colocalized with digestion spots in fluorescent substrate. We searched for other proteases involved in invadopodia activity. We have previously demonstrated that MMP9 influences adenoid cystic carcinoma behavior. This prompted us to investigate role played by MMP9 on invadopodia formation. CAC2 cells had MMP9 silenced by siRNA. After 1 h in fluorescent substrate, cells with silenced MMP9 showed clear decrease in matrix digestion compared with controls. No differences were found in cells with silenced MMP9 grown for 3 h on fluorescent substrate. Our results showed that CAC2 cells exhibit functional invadopodia containing cortactin and MT1‐MMP. Furthermore, MMP9 would be required in the initial steps of invadopodia formation. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Ultrastructure of the reproductive system of the black swamp snake (Seminatrix pygaea). VI. Anterior testicular ducts and their nomenclature
Authors: Sever David M. 
Published: August 2009

AbstractIn this study, the anterior testicular ducts of the North American natricine snake Seminatrix pygaea are described using light and electron microscopy. From the seminiferous tubules, the rete testis passes into the epididymal sheath, a structure along the medial border of the testis heavily invested with collagen fibers. The rete testis consists of simple, nonciliated cuboidal epithelium (principal cells). The intratesticular ducts of the rete testis are narrow (50–70 μm) at their junction with the seminiferous tubules, widen (80–100 μm) as they extend extratesticularly, and divide into smaller branches as they anastomose with the next tubules, the ductuli efferentes. The ductuli efferentes are lined by simple cuboidal epithelium but possess nonciliated principal cells as well as ciliated cells. These are the only ducts in the male reproductive system with ciliated cells. The ductuli efferentes are narrow (25–45 μm), divide into numerous branches, and are highly convoluted. The ductus epididymis is the largest duct in diameter (240–330 μm), and the diameter widens and the epithelium thins posteriorly. The ductus epididymis is lined by nonciliated, columnar principal cells and basal cells. No regional differences in the ductus epididymis are apparent. Ultrastructural evidence suggests that all of the nonciliated principal cells in each of the anterior testicular ducts function in both absorption and secretion. Absorption occurs via small endocytic vesicles, some of which appear coated. Secretion is by a constitutive pathway in which small vesicles and a flocculent material are released via a merocrine process or through the formation of apocrine blebs. The secretory product is a glycoprotein. Overall, the characteristics of the anterior testicular ducts of this snake are concordant with those of other amniotes, and the traditional names used for snakes are changed to conform with those used for other sauropsids and mammals. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.
4D‐analysis of early pelvic girdle development in the mouse (Mus musculus)
Authors: Pomikal Christine , Streicher Johannes 
Published: August 2009

AbstractThe formation of limb girdles is a key‐novelty in vertebrate evolution. Although the knowledge of pattern formation, genetic, and molecular analysis of limb development has prodigiously grown over the past four decades, the morphogenesis of the pelvic element, joining the appendicular with the axial skeleton has poorly been investigated. Because of their heterochrony in development and evolution, axial and appendicular skeletal elements have seldom been seen as a cojoined morphological complex. The present study examines the pelvis morphogenesis in the mouse (Mus musculus), with special focuses on the axio‐appendicular linkage, the formation and number of elements, and the joint formation. Serial histological sections of specimens from Theiler stages (TH) 18–25 (Theiler, 1972) were examined using bright field microscopy. 3D‐models of the growing pelvis were reconstructed from these serial sections. The generated 3D‐models were subsequently integrated into a computer‐animated 4D‐visualization illustrating the complex developmental dynamics of the mammalian pelvis morphogenesis. The findings demonstrate that the pelvic element forms from a single mesenchymal condensation in close vicinity to the appendicular skeleton. From the early start of development the pelvic element is limb‐associated, and quite lately connects to the axial skeleton. Additionally, the 4D‐visualization of the entire developmental process reveals a yet unnoticed reorientation of the mouse pelvic element from an initial posteriorly oblique developmental position to a ventrally oblique definitive position. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.
GAP43 overexpression and enhanced neurite outgrowth in mucopolysaccharidosis type IIIB cortical neuron cultures
Authors: Hocquemiller Michaël , Vitry Sandrine , Bigou Stéphanie , Bruyère Julie , Ausseil Jérôme , Heard Jean Michel 
Published: August 2009

AbstractBehavioral manifestations mark the onset of disease expression in children with mucopolysaccharidosis type III (MPSIII, Sanfilippo syndrome), a genetic disorder resulting from interruption of the lysosomal degradation of heparan sulfate. In the mouse model of MPSIII type B (MPSIIIB), cortical neuron pathology and dysfunction occur several months before neuronal loss and are primarily cell autonomous. The gene coding for GAP43, a neurite growth potentiator, is overexpressed in the MPSIIIB mouse cortex, and neurite dystrophy was reported in other types of lysosomal storage diseases. We therefore examined the development of the neuritic trees in pure populations of MPSIIIB mouse embryo cortical neurons grown for up to 12 days in primary culture. Dynamic observation of living neurons and quantification of neurite growth parameters indicated more frequent neurite elongation and branching and less frequent neurite retraction, resulting in a relative overgrowth of MPSIIIB neuron neuritic trees, involving both dendrites and axons, compared with normal controls. Neurite overgrowth was concomitant with more than twofold increased expression of GAP43 mRNAs and proteins. Correction of the genetic defect leads to expression of the missing lysosomal enzyme, normal GAP43 mRNA expression, and reduced neurite outgrowth. These results indicate that heparan sulfate oligosaccharide storage modifies GAP43 expression in MPSIIIB cortical neurons with potential consequences for neurite development and neuronal functions that may be relevant to clinical manifestations. © 2009 Wiley‐Liss, Inc.