Abstract:
:Rheumatoid synovial cell monolayers, with [1-14C]arachidonic acid ([1-14C]AA) incorporated into cell lipids, are stimulated by a factor (RSF) produced by explant cultures of rheumatoid synovial tissue to produce up to 50-fold increases in [1-14C]prostaglandin E2 and [1-14C]prostaglandin I2. In contrast, levels of free [1-14C]AA released from RSF-stimulated cells are generally lower than [1-14C]AA levels in cultures of untreated cells. These observations are inconsistent with a mechanism of prostaglandin stimulation consisting of an increase in phospholipase activity, because this mechanism would increase free AA levels as well as prostaglandins. A mechanism is proposed in which free AA is maintained at low steady-state levels by reacylation of free AA into phospholipids at a rate more rapid than its reaction with cyclooxygenase to form prostaglandins. In this mechanism, stimulation of the rate of the cyclooxygenase step by RSF accounts for increased prostaglandin synthesis as well as the decreased release of AA. On the basis of data previously reported by others, it is suggested that this mechanism may also be applicable to the stimulation of prostaglandin synthesis by several other agents. Preliminary characterization of the RSF indicates that it is a protein, and molecular seive chromatography indicates that its molecular weight is about 18,000. The production of RSF by rheumatoid synovial tissue is suppressed to undetectable levels by 1 microM dexamethasone.
journal_name
Proc Natl Acad Sci U S Aauthors
Robinson DR,Bastian D,Hamer PJ,Pichiarallo DM,Stephenson MLdoi
10.1073/pnas.78.8.5160subject
Has Abstractpub_date
1981-08-01 00:00:00pages
5160-4issue
8eissn
0027-8424issn
1091-6490journal_volume
78pub_type
杂志文章abstract::A 16-amino acid residue peptide derived from a consensus motif of natural ferredoxins incorporates a tetranuclear iron sulfur cluster under physiological conditions. Successful assembly of the [4Fe-4S]2+/1+ cluster within a monomeric peptide was demonstrated using size exclusion chromatography, UV-visible, visible CD,...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.26.15041
更新日期:1996-12-24 00:00:00
abstract::Hybridization of human T cells with an azaguanine-resistant human T cell line gave rise to T hybrid cell lines secreting several immunoregulatory molecules. Analyses of karyotypes, HLA phenotypes, and other surface phenotypes, such as T-cell-specific antigens or receptors for sheep erythrocytes and the patterns of mit...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.12.7717
更新日期:1981-12-01 00:00:00
abstract::Normal human cells whether embryonic, neonatal, or adult are resistant to experimentally induced tumorigenesis in contrast to rodent or chicken cells. We showed previously that neither transformation with simian virus 40 DNA nor transfection with human mutant HRAS DNA immortalized FS-2 cells (diploid, neonatal human f...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.22.8659
更新日期:1986-11-01 00:00:00
abstract::In an 1885 paper, E. Picard defined a subgroup Tau(Lambda) of PU(2,1) generated by monodromies and depending on parameters Lambda = (lambda(1),lambda(2),lambda(3),lambda(4)), 0 < lambda(i) < 1, < lambda(i) < 3, lambda(i) + lambda(j) >/= 1, 1 = i < j = 4. The family Tau(Lambda) resembles the family of groups Tau([u...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.10.5948
更新日期:1981-10-01 00:00:00
abstract::We have measured the angle-resolved transverse resistivity (ARTR), a sensitive indicator of electronic anisotropy, in high-quality thin films of the unconventional superconductor Sr2RuO4 grown on various substrates. The ARTR signal, heralding the electronic nematicity or a large nematic susceptibility, is present and ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1921713117
更新日期:2020-05-19 00:00:00
abstract::A unique property of the mammalian embryo is that stem cells can be derived from its early tissue lineages. These lineages will give rise to the fetus as well as essential extraembryonic tissues. Understanding how chromatin regulation participates in establishment of these lineages in the embryo and their derived stem...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0914507107
更新日期:2010-06-15 00:00:00
abstract::A biomimetic hydrogel platform was designed to signal encapsulated cells using immobilized cell-cell communication cues, with a focus on enhancing the survival and function of encapsulated pancreatic β-cells to treat type 1 diabetes. When MIN6 cells, a pancreatic β-cell line, were encapsulated in poly(ethylene glycol)...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1014026108
更新日期:2011-04-19 00:00:00
abstract::Site-specific recombination is responsible for a broad range of biological phenomena, including DNA inversion, resolution of transposition intermediates, and the integration and excision of bacteriophage genomes. Integration of mycobacteriophage L5 is catalyzed by a phage-encoded integrase with recombination occurring...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.140014297
更新日期:2000-07-05 00:00:00
abstract::The B cell developmental pathway represents a leading system for the analysis of regulatory circuits that orchestrate cell fate specification and commitment. Considerable progress has been achieved within the past decade in the identification and genetic analysis of various regulatory components. These components incl...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.0500480102
更新日期:2005-04-05 00:00:00
abstract::How does genome evolution affect the rate of diversification of biological lineages? Recent studies have suggested that the overall rate of genome evolution is correlated with the rate of diversification. If true, this claim has important consequences for understanding the process of diversification, and implications ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1007888107
更新日期:2010-11-23 00:00:00
abstract::The DNA origami method permits folding of long single-stranded DNA into complex 3D structures with subnanometer precision. Transmission electron microscopy, atomic force microscopy, and recently cryo-EM tomography have been used to characterize the properties of such DNA origami objects, however their microscopic stru...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1316521110
更新日期:2013-12-10 00:00:00
abstract::Chloroplasts have evolved from a cyanobacterial endosymbiont and been retained for more than 1 billion years by coordinated chloroplast division in multiplying eukaryotic cells. Chloroplast division is performed by ring structures at the division site, encompassing both the inside and the outside of the two envelopes....
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0802412105
更新日期:2008-09-30 00:00:00
abstract::Rhythmic, spontaneously pulsating cardiac cells cultured from newborn rats are immediately stimulated to beat faster by addition of a number of tubulin-binding agents but not by their non-tubulin-binding analogues. The tubulin-binding agents tested include vinblastine, vincristine, navelbine, two analogs of vinblastin...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.89.4.1256
更新日期:1992-02-15 00:00:00
abstract::The trace metals nickel and platinum, which are not substrates for ferrochelatase and thus do not form heme in biological systems, were found to act similaryl to cobalt, and heme itself, in regulating heme metabolism in liver and kidney. These metals induced heme oxygenase activity in both organs with the peak of indu...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.74.5.1875
更新日期:1977-05-01 00:00:00
abstract::The vascular endothelial growth factor (VEGF) family has recently expanded by the identification and cloning of three additional members, namely VEGF-B, VEGF-C, and VEGF-D. In this study we demonstrate that VEGF-B binds selectively to VEGF receptor-1/Flt-1. This binding can be blocked by excess VEGF, indicating that t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.20.11709
更新日期:1998-09-29 00:00:00
abstract::The electrical response of a pigmented lipid bilayer to a short laser pulse is measured by a tunable voltage clamp method. In this method, a variable access impedance permits "tuning" of the observed relaxations for optimal measurements. Analysis of the data so obtained leads to an equivalent circuit that contains a n...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.71.4.1564
更新日期:1974-04-01 00:00:00
abstract::Because synaptic vesicle exocytosis is a nano-mechanical process, it should be influenced by the mechanical properties of the cell membrane to which the vesicle fuses. By dissolving surfactants at various concentrations in the neuronal membrane, we have perturbed mechanical properties of the membrane and have found th...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0809714105
更新日期:2008-11-18 00:00:00
abstract::The number of x-irradiated mammalian cells surviving is markedly increased when the cells are incubated with an uncoupler of oxidative phosphorylation prior to or immediately after irradiation. This increase is greater in plateau-phase cells than in exponentially growing cells. The increase in survival is related to t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.5.2702
更新日期:1980-05-01 00:00:00
abstract::Von Willebrand factor (vWF) was purified from the plasma of a patient with type IIB von Willebrand disease (vWF from such a patient, IIB vWF) who had a normal platelet count and showed no evidence of spontaneous platelet aggregation. Large multimers of IIB vWF were absent from purified preparations and from plasma. Ri...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.21.7424
更新日期:1985-11-01 00:00:00
abstract::The nonreceptor tyrosine phosphatase Shp2 (PTPN11) has been implicated in tyrosine kinase, cytokine, and integrin receptor signaling. We show here that conditional mutation of Shp2 in neural crest cells and in myelinating Schwann cells resulted in deficits in glial development that are remarkably similar to those obse...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0904336106
更新日期:2009-09-29 00:00:00
abstract::A reaction cycle for electron-transportdriven proton pumps is proposed. It includes two distinct conformational states of the pump protein in which the primary electron acceptor has different reduction potentials. This has as an unavoidable consequence that the steady-state rate equation for the catalytic reaction dri...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.12.4282
更新日期:1986-06-01 00:00:00
abstract::Previous reports have shown that γδ T cells are important for the elimination of malaria parasites in humans and mice. However, how γδ T cells are involved in protective immunity against blood-stage malaria remains unknown. We infected γδ T-cell-deficient (TCRδ-KO) mice and control wild-type mice with Plasmodium bergh...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1204480109
更新日期:2012-07-24 00:00:00
abstract::Drosophila ovo/svb (dovo) is required for epidermal cuticle/denticle differentiation and is genetically downstream of the wg signaling pathway. Similarly, a mouse homolog of dovo, movo1, is required for the proper formation of hair, a mammalian epidermal appendage. Here, we provide biochemical evidence that movo1 enco...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.092137099
更新日期:2002-04-30 00:00:00
abstract::In animals, fatty acid desaturases catalyze key reactions in the synthesis of arachidonic acid and other polyunsaturated fatty acids. A search of the Caenorhabditis elegans DNA databases, using the sequences of Arabidopsis genes, identified several putative desaturases. Here we describe the characterization of the fir...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.4.1142
更新日期:1997-02-18 00:00:00
abstract::Tetherin/BST2 is a type-II membrane protein that inhibits the release of a range of enveloped viruses, including HIV-1. Here we report three crystal structures of human tetherin, including the full-length ectodomain, a triple cysteine mutant and an ectodomain truncation. These structures show that tetherin forms a con...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1011485107
更新日期:2010-10-26 00:00:00
abstract::Recombinant techniques allow one to engineer an antibody molecule and, in this way, manipulate its properties and functions. We engineered a chimeric human/mouse antibody to the tumor-associated antigen ganglioside GD2, with the aim of decreasing its serum half-life, maintaining its full antigen-binding capacity, and ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.15.5702
更新日期:1990-08-01 00:00:00
abstract::Animal development is remarkably robust; cell fates are specified with spatial and temporal precision despite physiological and environmental contingencies. Favorable conditions cause Caenorhabditis elegans to develop rapidly through four larval stages (L1-L4) to the reproductive adult. In unfavorable conditions, L2 l...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0908131106
更新日期:2009-11-03 00:00:00
abstract::Nucleotide sequences that direct transcription of the human 5-lipoxygenase gene have been examined by ligation to the chloramphenicol acetyltransferase gene and determination of chloramphenicol acetyltransferase activity in transfected HeLa and HL-60 cells. Various lengths of 5'-flanking sequences up to 5.9 kilobase p...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.23.9073
更新日期:1990-12-01 00:00:00
abstract::We have developed an in vitro transcription system that uses nuclei isolated from Lemna gibba G-3. The in vitro transcripts include sequences homologous to hybridization probes for the small subunit of ribulose-1,5-bisphosphate carboxylase [3-phospho-D-glycerate carboxy-lyase (dimerizing), EC 4.1.1.39], the light-harv...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.81.4.1112
更新日期:1984-02-01 00:00:00
abstract::Insulin provides a classical model of a globular protein, yet how the hormone changes conformation to engage its receptor has long been enigmatic. Interest has focused on the C-terminal B-chain segment, critical for protective self-assembly in β cells and receptor binding at target tissues. Insight may be obtained fro...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1412897111
更新日期:2014-08-19 00:00:00