bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prostaglandin E2 primes naive T cells for the production of anti‐inflammatory cytokines
Authors: Demeure Christian E. , Yang Liang‐Peng , Desjardins Céline , Raynauld Pierre , Delespesse Guy 
Published: March 2007

AbstractIn addition to their capacity to induce pain, vasodilatation and fever, prostaglandins E (PGE) exert anti‐inflammatory activities by inhibiting the release of pro‐inflammatory cytokines by macrophages and T cells, and by increasing interleukin (IL)‐10 production by macrophages. We here report that PGE2, the major arachidonic acid metabolite released by antigen‐presenting cells (APC), primes naive human T cells for enhanced production of anti‐inflammatory cytokines and inhibition of pro‐inflammatory cytokines. Unfractionated as well as CD45RO−CD31+ sort‐purified neonatal CD4 T cells acquire the capacity to produce a large spectrum of cytokines after priming with anti‐CD3 and anti‐CD28 monoclonal antibodies (mAb), in the absence of both APC and exogenous cytokines. PGE2 primes naive T cells in a dose‐dependent fashion for production of high levels of IL‐4, IL‐10 and IL‐13, and very low levels of IL‐2, interferon (IFN)‐γ, tumor necrosis factor (TNF)‐α, and TNF‐β. PGE2 does not significantly increase IL‐4 production in priming cultures, whereas it suppresses IL‐2 and IFN‐γ. Addition of a neutralizing mAb to IL‐4 receptor in primary cultures, supplemented or not with PGE2, prevents the development of IL‐4‐producing cells but does not abolish the effects of PGE2 on IL‐10 and IL‐13 as well as T helper (Th)1‐associated cytokines. Addition of exogenous IL‐2 in primary cultures does not alter the effects of PGE2 on naive T cell maturation. Thus PGE2 does not act by increasing IL‐4 production in priming cultures, and its effects are partly IL‐4 independent and largely IL‐2 independent. Together with the recent demonstration that PGE2 suppresses IL‐12 production, our results strongly suggest that this endogenously produced molecule may play a significant role in Th subset development and that its stable analogs may be considered for the treatment of Th1‐mediated inflammatory diseases.
Study of the Defects in Sintered SnO2 by High‐Resolution Transmission Electron Microscopy and Cathodoluminescence
Authors: Maestre David , Ramírez‐Castellanos Julio , Hidalgo Pedro , Cremades Ana , González‐Calbet José M. , Piqueras Javier 
Published: March 2007

AbstractThe defect structure of sintered SnO2 was investigated by high‐resolution transmission electron microscopy (HRTEM), cathodoluminescence (CL), and electrical measurements. HRTEM shows the presence of the SnO phase in the sintered samples as well as twinning, stacking faults, and disordered intergrowths. The sintered samples annealed under an oxygen atmosphere show changes in the defect structure and in the CL spectra. In particular, the intensity of a CL band at 1.94 eV, related to oxygen vacancies, decreased as the electrical resistivity increased. The results are discussed by considering the presence of stoichiometric defects such as oxygen vacancies and Sn interstitials in the final structure and their evolution during the annealing process under an oxygen atmosphere. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Spin‐Crossover Studies on a Series of 1D Chain and Dinuclear Iron(II) Triazine‐Dipyridylamine Compounds (Eur. J. Inorg. Chem. 8/2007)
Authors: Neville Suzanne M. , Leita Ben A. , Offermann Daniel A. , Duriska Martin B. , Moubaraki Boujemaa , Chapman Karena W. , Halder Gregory J. , Murray Keith S. 
Published: March 2007

AbstractThe cover picture shows the one‐dimensional polymeric iron(II) spin crossover material, Fe(NCX)2(cddt)·n(guest) (X = S or Se) containing the ligand 2‐chloro‐4,6‐bis(dipyrid‐2‐ylamino)‐1,3,5‐triazine. The thiocyanate analogue undergoes a “half” spin crossover, illustrated at the bottom, where at low temperatures there are alternating, crystallographically distinct, high spin (yellow) and low spin (red) iron(II) centres (as can be seen in the structural diagram). The selenocyanate material undergoes a full spin crossover illustrated at the base of the image. Further characterisation of the thiocyanate material has been carried out by powder X‐ray diffraction using synchrotron radiation; a representative image is shown in the background of the picture. Details are discussed in the article by K. S. Murray et al. on p. 1073 ff.
Biofilm growth kinetics on hydrocarbon in a porous medium under biostimulation conditions
Authors: Joannis‐Cassan C. , Delia M.‐L. , Riba J.‐P. 
Published: March 2007

AbstractThe formation of biofilm on hydrocarbon in a porous medium under biostimulation conditions was investigated in order to a better understanding of microbial development during bioremediation of hydrocarbon‐contaminated soils. Pseudomonas alkanolytica ATCC 21034 was studied as it grows embedded in a biofilm on dodecane surface. First, an experimental protocol for determination of biofilm growth kinetics on hydrocarbon in a porous medium was proposed. Six identical columns packed with sand were run simultaneously. The growth kinetics was obtained by measuring the biofilm dry weight of each column at different times. The reproducibility of the experimental protocol was validated using statistical tests. Then biofilm growth kinetics was established in the porous medium for two specific surfaces of dodecane (large or small droplets). A linear growth was observed due to transport limitation of both dodecane and dissolved oxygen in the biofilm. So the degradation of dodecane was uncompleted. Moreover, difficulty to bring dissolved oxygen in the deeper part of the porous medium was pointed out. All these phenomena could explain some failures encountered during biostimulation processes. © 2007 American Institute of Chemical Engineers Environ Prog, 2007
Synthesis, structures, and luminescence properties of ternary supramolecular hydrogen‐bonded complexes involving [(o‐C6F4)Hg]3, carbazole, and a Lewis base
Authors: Burress Charlotte N. , Gabbaï François P. 
Published: March 2007

AbstractThe interaction of trimeric perfluoro‐ortho‐phenylene mercury (1) with carbazole in dichloromethane, THF, and THF/NEt3 leads to the crystallization of [1·C12H8NH] (2), [1·(C12H8NH·THF)] (3), and [1·(C12H8NH·NEt3)] (4), respectively. Adducts 3 and 4 have been characterized by elemental analysis, IR spectroscopy, and luminescence spectroscopy. The crystal structures of 3 and 4 have also been determined. Both adducts have extended structures that exhibit supramolecular binary stacks, where molecules of 1 and the carbazole–Lewis base complex alternate. Short Hg–C contacts involving molecules of 1 and carbazole indicate the presence of secondary Hg–π interactions. In addition, adducts 3 and 4 display hydrogen‐bonding interactions between the acidic NH moiety of carbazole and the heteroatom of the Lewis base. The presence of this hydrogen bond is also confirmed by IR spectroscopy, which shows that the νNH of 3 and 4 is lower than that of 2. The luminescence spectra of these adducts correspond to the phosphorescence of carbazole, which is induced by the mercury heavy atom effect. In the case of 3 and 4, additional low‐energy bands are observed at 578 and 567 nm. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:195–201, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20329
Extracellular adenosine triphosphate induces glutamate transporter‐1 expression in hippocampus
Authors: Frizzo Marcos E. , Frizzo Juliana K. , Amadio Susanna , Rodrigues Juliana M. , Perry Marcos L. , Bernardi Giorgio , Volonté Cinzia 
Published: March 2007

AbstractATP can be significantly released following various brain insults and activates the extracellular signal‐regulated protein kinase (ERK) pathway in astrocytes. Glutamate transporter‐1 (GLT1) is the major forebrain astroglial glutamate transporter and its expression is stimulated also via ERK1/2 phosphorylation. We thus hypothesized that extracellular ATP could be a signal to GLT1 modulation in hippocampal slices obtained from rat. We indeed observed by western blot analysis that, after 1 mM ATP exposure, GLT1 expression, but not the glutamate–aspartate transporter, was enhanced. At the same time, high ATP induced significant rates of cell death in piramidal and granule cell layers, as shown by propidium iodide uptake, and increased glutamate uptake through GLT1 transporter. Also using confocal laser‐scanning microscopy, we observed that ATP induced a vigorous and extensive GLT1‐labeling on glial fibrillary acidic protein‐positive cells. This stimulation was abolished by purine/pyrimidine nucleotide receptor antagonists and by MEK1/2 inhibitor. The present study demonstrates a novel mechanism of GLT1 regulation by extracellular ATP, reinforcing the evidence of cross talk between glutamatergic and purinergic systems. © 2007 Wiley‐Liss, Inc.
A quantum chemistry study: A new kind of boron nitrides
Authors: Li Qian Shu , Xu Yu 
Published: March 2007

AbstractAt the B3LYP/6‐311+G** and the BP86/6‐311+G** levels of theory, BNN, H3BNN, NNBH2‐BH2NN, (BNN)2H2, NNBBNN, (BNN), (BNN)4, (BNN), (BNN), B4(NN)2, (BNN), (BNN)6, (BNN), and (BNN) are investigated. Neutral (BNN)4 is aromatic with its triplet state but antiaromatic with its singlet state. (BNN)4 dication favors D2d structure, while (BNN)4 dianion favors a planar D4h structure. (BNN), (BNN), (BNN), (BNN)6, (BNN), (BNN), (BNN), and (BNN) are all aromatic with planar monocyclic conformation, following the 4n + 2 rule. Moreover, according to the CASSCF and MRCI calculations, the planar B4(NN)2 of D2h symmetry prefers to be a σ‐π diradical in spite of open‐shell singlet or triplet and is also aromatic. Akin to the σ‐π back interaction in compounds containing transition metal, there exists the σ‐π back interaction between boron and N2 ligand among some species reported herein, which strengthens B−N bond but activates NN bond, especially in 4Σ− BNN. The T‐shaped structure lies lowest in energy among seven isomers of the (BNN)2H2 dimer, and the parallel‐displaced structure is favored between two isomers of the (BNN)6 dimer. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
Generation and characterization of tTS‐H4: a novel transcriptional repressor that is compatible with the reverse tetracycline‐controlled TET‐ON system
Authors: Bockamp Ernesto , Christel Cerstin , Hameyer Dorothe , Khobta Andriy , Maringer Marko , Reis Marco , Heck Rosario , Cabezas‐Wallscheid Nina , Epe Bernd , Oesch‐Bartlomowicz Barbara , Kaina Bernd , Schmitt Steffen , Eshkind Leonid 
Published: March 2007

AbstractBackgroundConditional gene regulatory systems ensuring tight and adjustable expression of therapeutic genes are central for developing future gene therapy strategies. Among various regulatory systems, tetracycline‐controlled gene expression has emerged as a safe and reliable option. Moreover, the tightness of tetracycline‐regulated gene switches can be substantially improved by complementing transcriptional activators with antagonizing repressors.MethodsTo develop novel tetracycline‐responsive transcriptional repressors, we fused various transcriptional silencing domains to the TetR (B/E) DNA‐binding and dimerization domain of the Tn10‐encoded tetracycline resistance operon (TetR (B/E)). The resulting fusion proteins were individually tested for their ability to repress transcription of the constitutively active hypoxanthine phosphoribosyltransferase (HPRT) promoter. In addition, compatibility with the commonly used reverse tetracycline‐controlled transactivator system (rtTA‐system) and responsiveness to the pharmacological effector doxycycline (DOX) were evaluated. Finally, inducibility, effector‐dependent promoter activity and the modification of histone H3 and H4 of the active versus the repressed target promoter were determined.ResultsFusion of the human deacetylase 4 (HDAC4) carboxy‐terminal silencing domain to TetR (B/E) resulted in a functional transcriptional repressor. This novel repressor, termed tTS‐H4, efficiently reduced the activity of the murine HPRT promoter and a constitutively active human cytomegalovirus (hCMV) minimal promoter. Furthermore, combining tTS‐H4 with the rtTA transcriptional activator allowed for grading, turning off and resuming target gene expression over several orders of magnitude without background.ConclusionsThe tTS‐H4 repressor is compatible with the commonly used rtTA transcriptional activation system and is a versatile new tool for tightly and adjustably regulating conditional gene expression. Copyright © 2007 John Wiley & Sons, Ltd.
Studies of an outbreak of acute hepatitis A: I. Complement level fluctuation
Authors: Baer G. M. , Walker J. A. , Yager P. A. 
Published: March 2007

AbstractAn outbreak of hepatitis A occurred in a rural elementary school in Colbert County, Alabama, in October and November 1972. The outbreak was caused by sewage‐contaminated drinking water and involved 49 children and 1 adult. Acute and convalescent serum samples were obtained from the hepatitis patients, and from each of 24 unafflicted matched controls at the same time. Strikingly, the levels of the third and fourth components of complement (C'3 and C'4) were markedly reduced in the acute samples from the sick children but returned to normal in the convalescent ones; the C'3 and C'4 levels in the healthy matched controls were not reduced. In addition, antigen‐antibody complexes were found in convalescent sera from some of the sick children. These findings indicate that immune complexes are present in acute hepatitis A and suggest that the techniques for future virus isolation may have to be altered.
Studies of an outbreak of acute hepatitis A: II. Antibody changes to cytomegalovirus and herpesvirus
Authors: Baer G. M. , Yager P. A. , Hierholzer J. C. , Walker J. A. , Almeida J. D. 
Published: March 2007

AbstractThe acute and convalescent sera from 14 schoolchildren with acute hepatitis A were tested for antibody changes to 70 viral antigens. Marked decreases were noted in the levels of antibody to cytomegalovirus in 5 of the 14 children and in the levels of antibody to herpesvirus type 1 in 3. No such changes were noted in 9 sex‐ and age‐matched healthy control children from the same classes.
The effect of intradermal administration of corynebacterium parvum on the immune response to hepatitis Bs antigen
Authors: Papaevangelou G. , Sparros L. , Vissouls Ch. , Kyriakidou A. , Giokas G. , Hadzimanolis J. , Trichopoulos D. 
Published: March 2007

AbstractThe immunopotentiating effect of the intradermal administration of a course of four doses (0.25 ml) of a standard suspension of killed C. parvum (2 mg/ml) was studied in a group of 10 asymptomatic chronic hepatitis B surface antigen (HBsAg) carriers, as well as in 11 persons with antibodies to HBsAg (anti‐HBs) and six without HBsAg or anti‐HBs. HBsAg, anti‐HBs, and leukocyte migration inhibition (LMI) studies were performed in pre‐ and post‐inoculation blood samples. C. parvum produced a substantial increase of anti‐HBs titre in persons with preexisting anti‐HBs. However, anti‐HBs responses were not induced in carriers. HBsAg was not eliminated and its titre remained practically unchanged in carriers. These results support the hypothesis that in carriers the specific defect in the immune response to HBsAg possibly exists at the B cell level.
The virion and soluble antigen proteins of variola, monkeypox, and vaccinia viruses
Authors: Esposito Joseph J. , Obijeski John F. , Nakano James H. 
Published: March 2007

AbstractThe structural proteins in purified preparations of variola, monkeypox, and vaccinia viruses were separated and compared by using a high resolution SDS‐polyacrylamide gel electrophoresis system. About 30 proteins were resolved for each virus by autoradiography of longitudinally‐sliced gel rods. Although the autoradioelectropherograms of each virus were similar, it was possible to differentiate them by their unique protein pattern in the 30,000 to 40,000 molecular weight region of the gels. A single virion glycoprotein (mol. wt. = 38 × 103) and a virion phosphoprotein (mol. wt. = 12 × 103) were associated with each of the virus preparations.Cross‐absorbed monospecific immune sera against variola, monkeypox, and vaccinia virus‐infected cells were used in immunodiffusion tests to precipitate radiolabeled, homologous, soluble antigen proteins. The predominant antigen protein associated with each immunospecific precipitate had a molecular weight of approximately 73,000.
Biological and biochemical characterization of a latent subacute sclerosing panencephalitis (SSPE) virus infection in tissue culture
Authors: Kratzsch Volker , Hall William W. , Nagashima Kazuo , ter Meulen Volker 
Published: March 2007

AbstractThe present investigation describes the biological and biochemical properties of a persistent SSPE virus infection. Persistently infected cells were derived by cocultivation of infected brain cells and uninfected Vero cells, and cultures were maintained by normal subculturing methods.No infectious virus was ever released from these cultures, and all attempts to induce infectious virus release were unsuccessful. Biological assays showed that infected cells contained nucleocapsid and salt‐dependent hemagglutinin antigens, whereas the normal hemagglutinin appeared not to be present. Electron microscopic examination demonstrated the presence of both intranuclear and cytoplasmic nucleocapsids together with the release of virus particles (defective?) from the cell membrane.Biochemical analysis demonstrated that approximately 90% of the intracellular genomic RNA was defective or subgenomic although a small quantity of infectious genomes was present.It is proposed that the large quantities of defective genomes in the infected cells are the major factor in the maintenance of this persistent infection.
Seroepidemiological investigation of patients and family contacts in an epidemic of hepatitis A
Authors: Frösner Gert G. , Overby Lacy R. , Flehmig Bertram , Gerth Hans‐Joachim , Haas Hans , Decker Richard H. , Ling Chung‐Mei , Zuckerman Arie J. , Frösner Helga‐Ruth 
Published: March 2007

AbstractSerial blood and faecal samples were collected from patients and family contacts during an outbreak of hepatitis A in a village and tested by a solid‐phase competitive type radioimmunoassay for hepatitis A antigen and hepatitis A antibody. The amount and duration of excretion of hepatitis A antigen was correlated with the severity of the illness. In 2 severe clinical cases, hepatitis A antigen was demonstrated in faecal extracts 11 days before the onset of jaundice and continuing for 10 days thereafter, with maximum shedding during the late incubation period. Faecal antigen was demonstrated in low concentrations for only 2 days in a patient with mild disease and in a person with subclinical infection. There was an inverse correlation between the incidence of infection and prevalence of hepatitis A antibody and age. Of 24 infections, 19 (79%) occurred in persons in the age group 0 to 20 years, a group in which only 6% of individuals had pre‐existing antibody. Hepatitis A antibody was present in the serum of 3 persons in low titres of 1:20 to 1:40 on the day jaundice developed. The antibody titres increased very rapidly during the following 2 weeks of illness and slowly during the following months, reaching titres of 1:900 to 1:3500. In a separate study, a mean antibody titre of 1:591 was found in 13 patients, 12 years after clinical hepatitis A with jaundice.
Acute optic neuritis: A virological study in relation to multiple sclerosis
Authors: Santoli Daniela , Wroblewska Zofia , Cremer Natalie E. , Lief Florence S. , Schatz Norman 
Published: March 2007

AbstractPrevious ultrastructural examination of peripheral blood lymphocytes revealed the presence of intranuclear filamentous structures in multiple sclerosis (MS) and in some optic neuritis (ON) patients. The present investigation was undertaken in the attempt to correlate the presence of such structures with the etiology of ON and MS and possibly to demonstrate the viral origin of the filaments. Suitable virological and serological techniques were used to detect and isolate infectious agents from peripheral blood samples and body excretions of 12 monosymptomatic ON patients at their first acute attack. Nevertheless, any efforts to demonstrate the presence of a virus in these patients have been unsuccessful: no evidence of active viral infection was obtained by serological studies of serum and cerebrospinal fluid samples, nor could viral antigens or inclusions be observed by immunofluorescence and cytochemical analysis. Negative results were also obtained from studies performed in parallel on MS patients and various controls. The significance of the failure to isolate infectious agents from either ON and MS patients is discussed.
Immunotherapy of viral infections with transfer factor
Authors: Mazaheri M. R. , Hamblin Anne S. , Zuckerman A. J. 
Published: March 2007

AbstractIt has been reported that dialysable leucocyte extract preparations, thought to contain transfer factor, may be used therapeutically for the treatment of a variety of immunodeficiency syndromes. Clinical and laboratory studies have suggested that such preparations, in addition to transferring specific cellular immunity may also contain non‐specific adjuvant activities. Attempts at immunotherapy of viral infections are described against a background of current research on the biological and biochemical properties of leucocyte dialysates.
Picorna‐ and togavirus infection of cells detected by gas chromatography
Authors: Levanon A. , Klibansky Y. , Kohn A. 
Published: March 2007

AbstractViral infection of cells causes chemical and metabolic changes, which can be detected by gas chromatography (GC) of ether extracts of supernatant fluids and cell homogenates. before any significant damage to the cells is observable microscopically. The characteristic and specific GC patterns obtained from BHK‐21 and Vero cell cultures infected with encephalomyocarditis, polio, echoviruses, and a togavirus make it possible to distinguish between these infecting viruses. The appearance of 1 or 2 compounds, represented by GC peaks with TR values of 302 and 677 seconds seems to be specific for these viruses. Other peaks found in the supernatant media 1–2 hours after infection probably represent cell constituents leaking into the medium as a result of damage to the cell membrane by the invading virus.
Tampon culture for quantitation of cervicovaginal herpes simplex virus
Authors: Ekwo Edem E. , Myers Martin G. 
Published: March 2007

AbstractFrom 101 to 106 TCID50 (mean tissue culture infective doses) per ml HSV I and II can be quantitatively recorded from vaginal tampons. Tampons and sterile cotton swabs are equally sensitive in recovering HSV I and II. Direct cotton swab cultures of the cervix and cervicovaginal tampon cultures from the same patients recovered similar quantities of HSV, ranging from 1.5 to 6.5 log10 TCID50 /ml in 5 patients.