Abstract:
:Low density lipoprotein (LDL) isolated from human plasma anticoagulated with EDTA (EDTA/LDL) was 4-fold more resistant to oxidation by reagent H2O2, as assayed by the thiobarbituric acid (TBA) assay, than LDL prepared from plasma anticoagulated with citrate (CDP/LDL). The LDLs required 1-3 mM H2O2 for maximal oxidation by this assay, and ED50S were 1.7 X 10(-3) M for EDTA/LDL and 4.5 X 10(-4) M for CDP/LDL. Oxidation was enhanced 2.3-fold by Cu2+ ions. Rabbit endothelial cell line monolayers released two orders of magnitude less H2O2 than was required to oxidize LDL and failed to induce TBA reactivity in either EDTA/LDL or CDP/LDL after a 24-hr coincubation. However, this LDL was subsequently degraded by mouse macrophages more rapidly than untreated LDL. Freshly isolated human monocytes (2 X 10(6) cells per ml), with or without phorbol myristate acetate (100 ng/ml) to trigger the respiratory burst, did not oxidize LDL in the TBA assay, despite producing large amounts of reactive oxygen intermediates. EDTA/LDL, CDP/LDL, and acetoacetylated LDL failed to trigger H2O2 release from human monocytes or macrophages. These results separate oxidation of LDL as measured by TBA assay from the modification of LDL by rabbit aortic endothelial cell line that leads to its subsequent enhanced degradation by macrophages.
journal_name
Proc Natl Acad Sci U S Aauthors
Montgomery RR,Nathan CF,Cohn ZAdoi
10.1073/pnas.83.17.6631subject
Has Abstractpub_date
1986-09-01 00:00:00pages
6631-5issue
17eissn
0027-8424issn
1091-6490journal_volume
83pub_type
杂志文章abstract::Adenosine deaminases that act on RNA (ADARs) constitute a family of RNA-editing enzymes that convert adenosine to inosine within double-stranded regions of RNA. We previously developed a method to identify inosine-containing RNAs and used it to identify five ADAR substrates in Caenorhabditis elegans. Here we use the s...
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.112704299
更新日期:2002-06-11 00:00:00
abstract::Several disulfide benzamides have been shown to possess wide-spectrum antiretroviral activity in cell culture at low micromolar to submicromolar concentrations, inhibiting human immunodeficiency virus (HIV) type 1 (HIV-1) clinical and drug-resistant strains along with HIV-2 and simian immunodeficiency virus [Rice, W. ...
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.93.3.969
更新日期:1996-02-06 00:00:00
abstract::The chloroplast stromal proteins from spinach condense the two heterocyclic moieties of vitamin B1--4-methyl-5-(beta-hydroxyethyl)thiazole and 2-methyl-4-amino-5-hydroxymethylpyrimidine--in the presence of MgATP. We have taken advantage of this observation to study thiazole synthesis. We present data indicating that 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.88.6.2042
更新日期:1991-03-15 00:00:00
abstract::Pancreatic islets regulate glucose homeostasis through coordinated actions of hormone-secreting cells. What underlies the function of the islet as a unit is the close approximation and communication among heterogeneous cell populations, but the structural mediators of islet cellular cross talk remain incompletely char...
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.2001936117
更新日期:2020-04-21 00:00:00
abstract::AcrAB is a constitutively expressed, major multidrug efflux system of Escherichia coli. We have purified the cytoplasmic membrane component, AcrB, to near homogeneity, and reconstituted the protein into proteoliposomes. In the presence of DeltapH (outside acid), the protein catalyzed the extrusion of fluorescent phosp...
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.96.13.7190
更新日期:1999-06-22 00:00:00
abstract::The membrane proteins of peripheral light-harvesting complexes (LHCs) bind chlorophylls and carotenoids and transfer energy to the reaction centers for photosynthesis. LHCs of chlorophytes, chromophytes, dinophytes, and rhodophytes are similar in that they have three transmembrane regions and several highly conserved ...
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.031587198
更新日期:2001-02-27 00:00:00
abstract::Due to its remarkably long half-life, together with its wide in vivo distribution and its lack of enzymatic or immunological functions, human serum albumin (HSA) represents an optimal carrier for therapeutic peptides/proteins aimed at interacting with cellular or molecular components of the vascular and interstitial c...
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.89.5.1904
更新日期:1992-03-01 00:00:00
abstract::One goal of regenerative medicine is to repair damaged tissue. This requires not only generating new cells of the proper phenotype, but also selecting for those that properly integrate into sites of injury. In our laboratory we are using a cell-migration-based in vivo selection system to generate antibodies that induc...
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.1719259115
更新日期:2018-01-16 00:00:00
abstract::Adipose tissue dysfunction is causally implicated in the impaired metabolic homeostasis associated with obesity; however, detailed mechanisms underlying dysregulated adipocyte functions in obesity remain to be elucidated. Here we searched for genes that provide a previously unknown mechanism in adipocyte metabolic fun...
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.1720475115
更新日期:2018-02-13 00:00:00
abstract::HIV type 1 (HIV-1) uses the chemokine receptors CCR5 and CXCR4 as coreceptors for entry into target cells. Here we show that the HIV-1 envelope gp120 (Env) activates multiple ionic signaling responses in primary human macrophages, which are important targets for HIV-1 in vivo. Env from both CCR5-dependent JRFL (R5) an...
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.090521697
更新日期:2000-04-25 00:00:00
abstract::The molecular weight of the major glycoprotein from the human erythrocyte membrane is 29,000, of which 55% is carbohydrate and 45% is protein. The binding of sodium dodecyl sulfate to this glycoprotein is anomalous when compared to water soluble proteins and leads to migration rates in sodium dodecyl sulfate-polyacryl...
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.71.10.3913
更新日期:1974-10-01 00:00:00
abstract::Marked hypoalphalipoproteinemia was found together with relatively low serum cholesterol, triacylglycerol, and LDL levels in a triose-phosphate isomerase (TPI; D-glyceraldehyde-3-phosphate ketol-isomerase, EC 5.3.1.1)-deficient Hungarian family, especially in the two compound-heterozygote brothers. Apart from a slight...
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.92.1.268
更新日期:1995-01-03 00:00:00
abstract::The putative oxidation of hydroethidine (HE) has become a widely used fluorescent assay for the detection of superoxide in cultured cells. By covalently joining HE to a hexyl triphenylphosphonium cation (Mito-HE), the HE moiety can be targeted to mitochondria. However, the specificity of HE and Mito-HE for superoxide ...
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.0601945103
更新日期:2006-10-10 00:00:00
abstract::The microvillus core-filament bundle from intestinal epithelial cells is a highly ordered structure containing actin and four major associated proteins. Two of these, villin and calmodulin, bind calcium ions (Kd approximately 10(-6) M) in the physiologically important range. Because ethylene glycol bis(beta-aminoethyl...
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.77.11.6458
更新日期:1980-11-01 00:00:00
abstract::The Lyz endolysin of bacteriophage P1 was found to cause lysis of the host without a holin. Induction of a plasmid-cloned lyz resulted in lysis, and the lytic event could be triggered prematurely by treatments that dissipate the proton-motive force. Instead of requiring a holin, export was mediated by an N-terminal tr...
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.0400957101
更新日期:2004-04-27 00:00:00
abstract::In a passive dendritic tree, inhibitory synaptic inputs activating ionic conductances with an equilibrium potential near the resting potential can effectively veto excitatory inputs. Analog interactions of this type can be very powerful if the inputs are appropriately timed and occur at certain locations. We examine w...
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.80.9.2799
更新日期:1983-05-01 00:00:00
abstract::Previous studies have shown that in mammalian cells proteins of large molecular weight are degraded more rapidly than small ones. Evidence is presented here that half-lives of proteins are also related to their isoelectric points. A double-isotope method was used to compare degradative rates of soluble proteins separa...
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.72.10.3893
更新日期:1975-10-01 00:00:00
abstract::Temperate-zone species have responded to warming temperatures by shifting their distributions poleward and upslope. Thermal tolerance data suggests that tropical species may respond to warming temperatures even more strongly than temperate-zone species, but this prediction has yet to be tested. We addressed this data ...
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.1318190111
更新日期:2014-03-25 00:00:00
abstract::A protein methylation reaction involved in chemotaxis of Escherichia coli has been identified. The involvement of this reaction in chemotaxis in indicated by four lines of evidence. (a) The methylation reaction is altered in several classes of generally nonchemotactic mutants and is coreverted with the chemotaxis defe...
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.72.10.3939
更新日期:1975-10-01 00:00:00
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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.0705195104
更新日期:2007-07-24 00:00:00
abstract::The rugged folding-energy landscapes of RNAs often display many competing minima. How do RNAs discriminate among competing conformations in their search for the native state? By using optical tweezers, we show that the folding-energy landscape can be manipulated to control the fate of an RNA: individual RNA molecules ...
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.0702137104
更新日期:2007-04-24 00:00:00
abstract::In addition to their well-recognized hepatotropism, all hepatitis B viruses (HBVs) display marked species specificity, growing poorly or not at all in species other than those closely related to their natural hosts. We have examined the molecular basis for this narrow host range, using duck HBV (DHBV) and heron HBV (H...
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.92.14.6259
更新日期:1995-07-03 00:00:00
abstract::Tumor-promoting phorbol esters affect the ability of mouse hematopoietic progenitor cells to form morphologically recognizable colonies in culture. They induce myeloid progenitor cells to form colonies of the monocyte/macrophage type in the absence of exogenous granulocyte/macrophage colony-stimulating factor. Convers...
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.78.7.4402
更新日期:1981-07-01 00:00:00
abstract::Genes encoding thymidylate synthetase from Bacillus subtilis bacteriophages were cloned in Escherichia coli. Chimeric plasmids pCD1 and pCD3 were constructed from site-specific endonuclease digests of bacteriophage phi3T DNA cloned in pMB9 in E. coli. Similar cloning techniques with bacteriophage beta22 DNA yielded ch...
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.75.8.3664
更新日期:1978-08-01 00:00:00
abstract::We recently showed that the mammalian genome encodes >1,000 large intergenic noncoding (linc)RNAs that are clearly conserved across mammals and, thus, functional. Gene expression patterns have implicated these lincRNAs in diverse biological processes, including cell-cycle regulation, immune surveillance, and embryonic...
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.0904715106
更新日期:2009-07-14 00:00:00
abstract::Calls for the eradication of malaria require the development of global and regional strategies based on a strong and consistent evidence base. Evidence from the previous global malaria eradication program and more recent transborder control campaigns have shown the importance of accounting for human movement in introd...
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.1002971107
更新日期:2010-07-06 00:00:00
abstract::Vascular endothelial growth factor receptor-3 (VEGFR-3) is a major mediator of lymphangiogenesis. Recently, VEGFR-3 ligands, VEGF-C, and VEGF-D were reported to promote tumor lymphangiogenesis and lymphatic metastasis, and these processes were inhibited by blocking of the VEGFR-3-signaling pathway. Here, we have adapt...
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.062040199
更新日期:2002-06-25 00:00:00
abstract::Hoxb13 is robustly transcribed in derivatives of posterior endoderm including the colon, rectum, and the prostate gland. Transcriptional activity in the prostate persists unabated under conditions of androgen deprivation and throughout the course of disease progression in a mouse prostate cancer model. To elucidate 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.0902001107
更新日期:2010-01-05 00:00:00
abstract::The chloroplast coupling factor 1 consists of five nonidentical subunits, three of which (alpha, beta, and epsilon subunits) have been shown in several laboratories to be synthesized within chloroplasts. The site of synthesis of the remaining two (gamma and delta subunits) was investigated by analyzing products direct...
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.79.20.6304
更新日期:1982-10-01 00:00:00
abstract::Human cells that suffer mild DNA damage can enter a reversible state of growth arrest known as quiescence. This decision to temporarily exit the cell cycle is essential to prevent the propagation of mutations, and most cancer cells harbor defects in the underlying control system. Here we present a mechanistic mathemat...
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.1715345115
更新日期:2018-03-06 00:00:00