bluuebunny/crossref_metadata_2025_split huggingface dataset:
Migration of human blood dendritic cells across endothelial cell monolayers: adhesion molecules and chemokines involved in subset-specific transmigration
Authors: de la Rosa Gonzalo , Longo Natividad , Rodríguez-Fernández Jose L , Puig-Kroger Amaya , Pineda Alfonso , Corbí Ángel L , Sánchez-Mateos Paloma 
Published: April 2003

Abstract
Distinct subsets of dendritic cells (DCs) are present in blood, probably “en route” to different tissues. We have investigated the chemokines and adhesion molecules involved in the migration of myeloid (CD11c+) and plasmacytoid (CD123+) human peripheral blood DCs across vascular endothelium. Among blood DCs, the CD11c+ subset vigorously migrated across endothelium in the absence of any chemotactic stimuli, whereas spontaneous migration of CD123+ DCs was limited. In bare cell migration assays, myeloid DCs responded with great potency to several inflammatory and homeostatic chemokines, whereas plasmacytoid DCs responded poorly to all chemokines tested. In contrast, the presence of endothelium greatly favored transmigration of plasmacytoid DCs in response to CXCL12 (stromal cell-derived factor-1) and CCL5 (regulated on activation, normal T expressed and secreted). Myeloid DCs exhibited a very potent transendothelial migration in response to CXCL12, CCL5, and CCL2 (monocyte chemoattractant protein-1). Furthermore, we explored whether blood DCs acutely switch their pattern of migration to the lymph node-derived chemokine CCL21 (secondary lymphoid-tissue chemokine) in response to microbial stimuli [viral double-stranded (ds)RNA or bacterial CpG-DNA]. A synthetic dsRNA rapidly enhanced the response of CD11c+ DCs to CCL21, whereas a longer stimulation with CpG-DNA was needed to trigger CD123+ DCs responsive to CCL21. Use of blocking monoclonal antibodies to adhesion molecules revealed that both DC subsets used platelet endothelial cell adhesion molecule-1 to move across activated endothelium. CD123+ DCs required β2 and β1 integrins to transmigrate, whereas CD11c+ DCs may use integrin-independent mechanisms to migrate across activated endothelium.
Leukocyte uropod formation and membrane/cytoskeleton linkage in immune interactions
Authors: Fais Stefano , Malorni Walter 
Published: April 2003

Abstract
The acquisition of a cell polarity is a crucial requirement for migration, activation, and apoptosis of leukocytes. The polarization of leukocytes involves the formation of two distinct poles: the leading edge—the attachment cell site to the substrate allowing directional movements of the cell—and on the opposite side, the uropod—mostly involved in cell-to-cell interaction and in a variety of leukocyte activities including activation and apoptosis. However, the uropod takes shape in neutrophils, monocytes, and natural killer cells, and the formation of this cell protrusion seems to exert an important role in immune interactions. In fact, the polarization sites of leukocytes are involved in a complex cross-talk between cells and extracellular matrix components, and a number of receptors and counter-receptors crowd in the contact sites to allow efficient cell-to-cell or cell–substrate interaction. The membrane/cytoskeleton interaction plays a crucial role in tuning these activities and in “predisposing” leukocytes to their function through the acquisition of a polarized phenotype. This review is focused on the mechanisms underlying the formation of the leukocyte uropod, the role of cytoskeleton in defining its structure and function, and the involvement of the uropod in the complex interplay between immune cells.
Ion channel gene expression in human lung, skin, and cord blood-derived mast cells
Authors: Bradding Peter , Okayama Yoshimichi , Kambe Naotomo , Saito Hirohisa 
Published: April 2003

Abstract
Immunoglobulin E (IgE)-dependent activation of human mast cells (HMC) is characterized by an influx of extracellular calcium (Ca2+), which is essential for subsequent release of preformed (granule-derived) mediators and newly generated autacoids and cytokines. In addition, flow of ions such as K+ and Cl− is likely to play an important role in mast cell activation, proliferation, and chemotaxis through their effect on membrane potential and thus Ca2+ influx. It is therefore important to identify these critical molecular efectors of HMC function. In this study, we have used high-density oligonucleotide probe arrays to characterize for the first time the profile of ion channel gene expression in human lung, skin, and cord blood-derived mast cells. These cells express mRNA for inwardly rectifying and Ca2+-activated K+ channels, voltage-dependent Na+ and Ca2+ channels, purinergic P2X channels, transient receptor potential channels, and voltage-dependent and intracellular Cl− channels. IgE-dependent activation had little effect on ion channel expression, but distinct differences for some channels were observed between the different mast cell phenotypes, which may contribute to the mechanism of functional mast cell heterogeneity.
DNA Dissolves Single-walled Carbon Nanotubes in Water
Authors: Nakashima Naotoshi , Okuzono Shingo , Murakami Hiroto , Nakai Tonau , Yoshikawa Kenichi 
Published: April 2003

Abstract
Transmission electron microscopy, atomic force microscopy, and UV-vis-NIR absorption spectroscopy have revealed that deoxyribonucleic acid (DNA) molecules dissolve single-walled carbon nanotubes in an aqueous solution.
Layered Organic–Inorganic Materials: A Way towards Controllable Magnetism
Authors: Rabu P. , Drillon M. 
Published: April 2003

AbstractThe search for new materials for tailor‐made applications and new devices involves not only solid‐state chemists, physicists or materials engineers, but also the area molecular and organo‐metallic chemistry, and even biochemistry. This is especially clear in the field of organic–inorganic multifunctional materials, whose design necessitates to investigate new concepts and principles developed in these different disciplines. Here, the authors review the structure‐magnetic property relationships in layered structures, made of organic and inorganic subunits.
Die Entwicklung der Sozialgeschichte der modernen Mathematik und Naturwissenschaft und die Frage nach dem sozialen Raum zwischen Disziplin und Wissenschaftler
Authors: Schirrmacher Arne 
Published: April 2003

AbstractThe use of the concept of social history of science is sketched in the Anglo‐American and the German discussions from the mid 1970s up to recent work. By presenting a ‘social map’ of a selected scientific community it is argued that between the categories of discipline and single scientist there exists a wide ‘social space’ of groups within which science is pursued. In adopting a milieu theoretic approach an ecology of science is proposed as a suitable extension of the social history of science.
Zwischen Naturphilosophie und Wissenschaftspolitik: Zum Profil der Isis oder Encyklopädischen Zeitschrift von Oken als naturwissenschaftliches Publikationsorgan in den Jahren 1817 bis 1822
Authors: Stiefel Katrin 
Published: April 2003

AbstractIsis oder Encyklopädische Zeitung, edited by the German natural philosopher Lorenz Oken (1779‐1851), is supposed to be one of the most significant journals of natural sciences in the early 19th century. The following study, based on a quantitative analyses of all articles (1817‐1822), investigates the profile of the natural sciences in this journal. The results are interpreted according to Oken's concept of the journal as well as his editorial notes. It is shown that the encyclopedically broadly designed journal focuses on the natural sciences as major part of it's content, presenting the descriptive history of natural sciences (Naturgeschichte) as main subject. The journal's research perspective follows the encyclopedical spread of issues and scientific subjects; a clear research profile of scientific disciplines can not be discerned. Although scientific subjects, issues and authors are heterogeneous, Oken preserves an inner coherence by a common perspective founded in natural philosophy: his strategy was therefore to interfere with the content of the articles by comments and footnotes. Finally it is shown that Oken's idea of encyclopedism and it's realisation in Isis comprises sciences as well as politics as two sides of the same coin: based on the philosophical understanding of the unity of nature Oken tries to educate the consciousness of his readers towards a socially and politically homogeneous nation.
Correction to Withdrawn Article[3,4] Cyclization Products of δ‐Oxo‐α,β‐unsaturated Ketoxime During Reaction with Hydrochloric Acid in Anhydrous Diethyl Ether
Authors: Uncuta Cornelia , Tudose Adriana , Caproiu Miron T. , Udrea Silvia , Roussel Christian 
Published: April 2003

AbstractWe have studied the cyclization of (4Z)‐2,2,5,8,8‐pentamethyl‐4‐nonene‐3,7‐dione (3E)‐oxime (2). We have previously claimed the formation of a stable 3,5,5‐trisubstituted 3‐isoxazolidinol and of a bridged bicycle 4,5‐dihydro‐2,5‐methano‐1,4,3‐dioxazepine in the reaction of 2 with hydrochloric acid in anhydrous diethyl ether. We report in this article that the above compounds are actually 3,3‐dimethyl‐1‐(5′‐tert‐butyl‐5′‐hydroxy‐3′‐methylisoxazolidin‐3′‐yl)butan‐2‐one (5) and 1,3‐di‐tert‐butyl‐5‐methyl‐2,7‐dioxa‐6‐azabicyclo[3.2.1]oct‐3‐ene (6). The formation of these products involves the splitting of hydroxylamine in 2 and its re‐addition as an O‐nucleophile under acidic reaction conditions. Surprisingly, 5 provided the 2‐isoxazoline derivative 3 on heating or on standing in CDCl3/TFA solution at room temperature. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Evaluation of thermotolerant coliforms and salinity in the four available water sources of an irrigated region of southern Sri Lanka
Authors: Shortt Rebecca , Boelee Eline , Matsuno Yutaka , Faubert Gaetan , Madramootoo Chandra , van der Hoek Wim 
Published: April 2003

AbstractIn many developing countries a close linkage exists between drinking and irrigation water; however, the effects of irrigation management on drinking water availability and quality, and what drinking water supplies are best suited to irrigated areas, have been little studied. Bacterial contamination and salinity of drinking water sources in a community within the Uda Walawe irrigation system of southern Sri Lanka were monitored from August to December 2000. Water with the lowest combination of faecal contamination and salt content (highest quality) was found in shallow wells, recharged with seepage water from the irrigation system. Of these wells, those surrounded by a protective wall had the lowest levels of thermotolerant coliforms (median of 244 ThCU 100 ml−1) as compared to shallow wells without protective walls (549 ThCU 100 ml−1). Furthermore, tube well waters were highly saline (average of 0.67 mS cm−1), while canal and reservoir waters had high thermotolerant coliform levels (3940 and 950 ThCU 100 ml−1). Interseasonal canal closures eliminate the canals as a water source, lowering water levels in shallow wells, and thus reducing regional water availability. Concrete lining of canals may exacerbate the drying up of shallow wells during canal closure, therefore eliminating the primary source of water in the region that can be used for drinking after only simple treatment. Copyright © 2002 John Wiley & Sons, Ltd.
Ab initio studies for the photodissociation mechanism of hydroxyacetone
Authors: Wu Yong , Xie Daiqian , Xue Ying 
Published: April 2003

AbstractThe reaction pathways for CH3COCH2OH (hydroxyacetone) photodissociation on the low‐lying electronic states have been studied with use of the CASSCF energy gradient techniques. The S0/S1 and S1/T1 intersection points were determined by the state‐average CASSCF method. Two main reaction pathways, which are possible to the photodissociation, have been studied. It has been found that the mechanism is stepwise, and belongs to Norrish type‐I reaction. The n → π* excitation leads to the first excited singlet state, followed by the intersystem crossing from S1 to T1. On the T1 potential energy surface, the system can dissociate adiabatically to CH3(x̃) +COCH2OH( x̃) and CH3CO(x̃)+CH2OH(x̃). The COCH2OH(x̃) and CH3CO(x̃) radicals can further dissociate into CO, OH, and other fragments. Our calculated results are in good agreement with recent experimental results. © 2003 Wiley Periodicals, Inc. J Comput Chem 8: 931–938, 2003
Rapid hyperpolarized 3He diffusion MRI of healthy and emphysematous human lungs using an optimized interleaved‐spiral pulse sequence
Authors: Salerno Michael , Altes Talissa A. , Brookeman James R. , de Lange Eduard E. , Mugler John P. 
Published: April 2003

AbstractPurposeTo develop and validate an interleaved‐spiral diffusion pulse sequence capable of hyperpolarized 3He MR imaging of the whole lung in less than 10 seconds.Materials and MethodsHyperpolarized 3He diffusion measurements were performed in seven healthy volunteers and five patients with emphysema using an interleaved‐spiral pulse sequence that provided 11 contiguous 15‐mm thick coronal ADC maps, with an in‐plane resolution of 3.9 mm, covering the whole lung in 5.5 seconds. The resulting means and SDs of ADC values were compared statistically to those from a gradient‐echo pulse sequence with identical resolution and diffusion‐weighting gradients that acquired five ADC maps in 10.5 seconds.ResultsHigh‐quality diffusion‐weighted interleaved‐spiral images covering the whole lung were obtained, and showed no significant susceptibility‐induced image degradation compared to corresponding gradient‐echo images. On a subject‐by‐subject basis, the means and SDs of ADC values for the interleaved‐spiral technique were not statistically different from those for the gradient‐echo technique. The mean ADC values from the two techniques were highly correlated on a section‐by‐section basis (R = 0.99).ConclusionThe interleaved‐spiral diffusion pulse sequence permits rapid acquisition of contiguous ADC maps covering the whole lung during a short breath‐hold period, and provides ADC values that are statistically equivalent to those from standard gradient‐echo techniques. J. Magn. Reson. Imaging 2003;17:581–588. © 2003 Wiley‐Liss, Inc.
Changes in amount of organic and inorganic fractions of nitrogen in an Eutrochrept soil after long‐term cropping with different fertilizer and organic manure inputs
Authors: Sammi Reddy Kotha , Singh Muneshwar , Tripathi Awadesh Kumar , Singh Mahavir , Saha Manbendra Nath 
Published: April 2003

AbstractThe influence of 30 years of cropping with different fertilizer and farmyard manure (FYM) inputs on the contents and depth distribution of organic C, total N (Nt), soil mineralizable N, and organic and inorganic N fractions was investigated in an Eutrochrept. Continuous application of 100 %NPK(+S), 150 %NPK(+S), and 100 %NPK(+S)+FYM led to a marked increase in organic C, total N, hydrolyzable N (viz., amino acid N, hydrolyzable NH4‐N, hexose amine N, and unidentified hydrolyzable N), and nonhydrolyzable N as compared to an adjacent fallow. The contents of the various organic N fractions were largest in surface soil and thereafter decreased with the depth. However, at 30 – 45 cm depth the content of organic C was not affected by the different treatments except 100 %NPK(+S)+FYM. On the other hand, continuous cropping without fertilization resulted in a depletion of total hydrolyzable N in control over fallow by 27.2 % (0–15 cm), 19.6 % (15–30 cm), and 4.7 % (30–45 cm). The incorporation of FYM with 100 %NPK(+S) resulted in greater contents of soil mineralizable N as compared to 100 %NPK(+S) (0–15, 15–30 cm). The proportion of hydrolyzable N (57–76 % of Nt) decreased and that of nonhydrolyzable N (22–40 % of Nt) increased with depth. The proportion of amino acid N (19–26 % of Nt), hexose amine N (2.1–3.5 % of Nt) and unidentified hydrolyzable N (17–27 % of Nt) decreased with depth. All organic soil N fractions including even nonhydrolyzable N in surface and subsurface soils were highly significantly correlated with soil mineralizable N derived from incubations under waterlogged and aerobic conditions. The best correlation to mineralizable N was found for amino acid N and the least significant correlation for nonhydrolyzable N.
Growth and phosphorus uptake of maize cultivated alone, in mixed culture with other crops or after incorporation of their residues
Authors: El Dessougi Hanadi , zu Dreele Alexander , Claassen Norbert 
Published: April 2003

AbstractIntercropping or rotating of P‐efficient crop species which mobilize sparingly soluble P by their root exudates can have beneficial effects on growth and P uptake of P‐inefficient species. We aimed at studying the effect of intercropping or incorporating of crop residues of P‐efficient crops on the components of maize P‐uptake, i.e. the root‐system size and P influx (P‐uptake rate per unit root length). This was studied in 3 pot experiments in a low‐P sandy soil. In the first experiment, maize was intercropped with white lupine, sugar beet or oilseed rape, and with groundnut in the second experiment. In the third experiment, maize was grown after incorporating the crop residues of white lupine, sugar beet or oilseed rape. Maize growth and yield was strongly inhibited when intercropped with white lupine, sugar beet or oilseed rape, probably because of competition for nutrients. But with groundnut as the accompanying species, maize yield was increased by a factor of 3, mainly because of an enhanced P influx. Crop residues of oilseed rape and sugar beet increased the yield of maize by factors 2 and 1.6, respectively, because of a 3 and 2 times higher P uptake as compared to maize grown after maize without incorporation of crop residue. The reason for the higher maize P‐uptake after oilseed rape was an 11 times higher P influx as compared to maize without crop residues, and after sugar beet residues because of an enhanced root growth and a 4 times higher P influx. Lupine residues did not improve maize growth, mainly because of a low P influx, which was even less than that of maize grown without crop residues. The soil solution P concentration and calcium acetate lactate‐extractable P (CAL P) measured in this study did not reflect the P availability as indicated by the plants (P uptake, P influx). This indicates that other mechanisms such as P mobilization in the rhizosphere by root exudates or cell‐wall components were responsible for the increased P availability. These mechanisms need further investigation.
On the Crystal Structure of cis‐1,4‐Poly(2,3‐dimethyl‐1,3‐butadiene)
Authors: Pirozzi Beniamino , Napolitano Roberto , Petraccone Vittorio , Esposito Simona 
Published: April 2003

AbstractModels for the crystal structure of cis‐1,4‐poly(2,3‐dimethyl‐1,3‐butadiene) are elucidated by the joint use of molecular mechanics and WAXS. The chain conformation can be predicted by using different sets of potential functions. A model of crystal structure calculated by molecular mechanics has been refined in order to find the best accordance with the experimental X‐ray powder spectra. Another model is proposed to explain a few minor discrepancies between the calculated and the experimental WAXS powder spectra.Portion of the chain of cis‐PDMBD, containing two monomer units with indications of the symmetry elements of the tci line repetition group, and of the bond and torsion angles of the backbone, which are independent variables.magnified imagePortion of the chain of cis‐PDMBD, containing two monomer units with indications of the symmetry elements of the tci line repetition group, and of the bond and torsion angles of the backbone, which are independent variables.
Variation in cyclooxygenase expression levels within the colorectum
Authors: Wiese Frederick W. , Thompson Patricia A. , Warneke James , Einspahr Janine , Alberts David S. , Kadlubar Fred F. 
Published: April 2003

AbstractThe positive association of decreased risk of colorectal cancer with nonsteroidal antiinflammatory drug (NSAID) use, combined with the observation that cyclooxygenase(COX)‐2 is present in a majority of colorectal tumors, has led to the proposed use of isozyme‐specific COX inhibitors as preventive agents in polyp and tumor formation in the colon. However, the exact biochemical mechanisms and disease stage at which reduced risk is mediated remain somewhat controversial, in part because of the complex biochemical changes that occur during the progression from aberrant crypt to polyp to tumor. In this study, COX‐1 and COX‐2 protein expression levels were determined in sets of tumor and normal colon tissue. Changes were characterized in COX‐1 and COX‐2 expression within individuals, in relation to such factors as sex, tumor grade, and location in the colorectum. COX‐1 expression levels were found to be significantly reduced in tumors compared to matched normal tissues (Dunn's method, P < 0.05). Additionally, COX‐1 expression was decreased in stage T3 tumors as compared to stage T2 tumors (Student's t‐test, P = 0.009). Similar to previous reports, COX‐2 protein expression was present in 73% of the tumors studied and appeared to be independent of tumor grade and sex. Interestingly, decreased COX‐2 expression correlated with tumor occurrence in rectal mucosa (Wilcoxon two‐sample test, P < 0.05). These results warrant further investigation, especially the identification of determinants that would predict which populations would be most responsive to COX‐2 inhibition as a means of colorectal cancer chemoprevention. Published 2003 Wiley‐Liss, Inc.
Characterisation of catalytic nucleic acids targeting the survival of motor neuron messenger RNA
Authors: Trülzsch Barbara , Davies Kay , Wood Matthew 
Published: April 2003

AbstractCatalytic nucleic acids have been used in a reverse genetics approach to study gene function. We are interested in applying this technology to study the autosomal recessive disease Spinal Muscular Atrophy (SMA) which is caused by loss of survival motor neuron gene (SMN) product leading to progressive motor neuron loss and muscular atrophy. Although the SMN gene is ubiquitously expressed, the cause for selective motor neuron loss is unknown. Embryonal lethality in mice has made it extremely difficult to generate animal models of SMA. We describe a procedure for selecting effective DNAzymes (DZ) and ribozymes (RZ) based on their ability to cleave the full length Smn mRNA at low magnesium concentrations, after a short time period, and at a low catalytic nucleic acid to target ratio. Using these criteria three effective RZ and DZ were generated. These results indicate that catalytic nucleic acids can effectively cleave Smn target RNA in an environment closely resembling that present in the cell and thus have potential for interference with Smn gene expression in cells and in vivo.
Cutting and Machining Energetic Materials with a Femtosecond Laser
Authors: Roeske Frank , Benterou Jerry , Lee Ronald , Roos Edward 
Published: April 2003

AbstractA femtosecond (fs) laser has been used as a tool for solving many problems involving access, machining, disassembly, inspection and avoidance of undesirable hazardous waste streams in systems containing energetic materials. Because of the unique properties of the interaction of ultrashort laser pulses with matter, the femtosecond laser can be used to safely cut these energetic materials in a precise manner without creating an unacceptable waste stream. Many types of secondary high explosives (HE) and propellants have been cut with the laser for a variety of applications ranging from disassembly of aging conventional weapons (demilitarization), inspection of energetic components of aging systems to creating unique shapes of HE for purposes of initiation and detonation physics studies. Hundreds of samples of energetic materials have been cut with the fs laser without ignition and, in most cases, without changing the surface morphology of the cut surfaces. The laser has also been useful in cutting nonenergetic components in close proximity to energetic materials.