Abstract:
:Plasma of normal human individuals was shown to contain an inhibitor of Trypanosoma cruzi neuraminidase (NAase; acylneuraminyl hydrolase, sialidase, EC 3.2.1.18). The inhibitor has been purified to homogeneity by PEG precipitation, CM Affi-Gel Blue Sepharose chromatography, and gel filtration. The purified preparation inhibits T. cruzi NAase at a concentration as low as 10(-9) M and has no effect at concentrations at least 100 times higher on any of the other NAases tested, including those from influenza virus, the closely related trypanosome Trypanosoma rangeli, and mammalian NAases. The inhibitor is unique in that it prevents T. cruzi desialylation of intact mammalian cells but does not prevent desialylation of soluble glycoconjugates. In addition, the isolated material is effective in inhibiting the T. cruzi NAase whether the enzyme is on the parasite outer membrane or in solution. Molecular characterization indicates that the inhibitor is a glycoprotein with a Mr of 246,000 +/- 20,000 composed of subunits of Mr 28,000 +/- 2000. Its plasma concentration is at least 60 micrograms/ml. The mechanism of action has not been fully elucidated, but it appears to be noncompetitive. Attempts to match the isolated NAase inhibitor with known plasma glycoproteins have not been successful. In view of this and of the specificity of the inhibitor for T. cruzi, we have named the inhibitor "cruzin." This finding suggests a different approach in investigating the role that NAase plays in host-parasite interaction.
journal_name
Proc Natl Acad Sci U S Aauthors
Prioli RP,Rosenberg I,Pereira MEdoi
10.1073/pnas.84.10.3097subject
Has Abstractpub_date
1987-05-01 00:00:00pages
3097-101issue
10eissn
0027-8424issn
1091-6490journal_volume
84pub_type
杂志文章abstract::We performed a genome-wide analysis of gene expression in primary human CD15(+) myeloid progenitor cells. By using the serial analysis of gene expression (SAGE) technique, we obtained quantitative information for the expression of 37,519 unique SAGE-tag sequences. Of these unique tags, (i) 25% were detected at high 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.051013798
更新日期:2001-03-13 00:00:00
abstract::Enhanced transductional recombination between specialized transducing phage lambda plac5 and plasmid F42lac depends on cis- and trans-acting factors. By constructing a series of recombinant molecules, the cis-acting site required for enhanced recombination has been identified as oriT, the origin of conjugational trans...
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.81.23.7500
更新日期:1984-12-01 00:00:00
abstract::Bone marrow mononuclear cells (BMC) from patients with ischemic cardiomyopathy (ICMP) show a reduced neovascularization capacity in vivo. NO plays an important role in neovascularization, and NO bioavailability is typically reduced in patients with ICMP. We investigated whether the impaired neovascularization capacity...
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.0604144103
更新日期:2006-09-26 00:00:00
abstract::Neonatal ablation of the suprachiasmatic nucleus in the rat has two important consequences. First, the direct projection from the retina to the suprachiasmatic nucleus fails to develop and no other retinal projection to any hypothalamic nucleus is formed. Second, circadian rhythms in drinking and spontaneous locomotor...
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.75.12.6243
更新日期:1978-12-01 00:00:00
abstract::Aneuploidy is ubiquitous in cancer, and its phenotypes are inevitably dominant and abnormal. In view of these facts we recently proposed that aneuploidy is sufficient for carcinogenesis generating cancer-specific aneusomies via a chain reaction of autocatalytic aneuploidizations. According to this hypothesis a carcino...
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.251670699
更新日期:2002-05-14 00:00:00
abstract::Early forms of the genetic code likely generated "statistical" proteins, with similar side chains occupying the same sequence positions at different ratios. In this scenario, groups of related side chains were treated by aminoacyl-tRNA synthetases as a single molecular species until a discrimination mechanism develope...
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.2136794100
更新日期:2003-12-23 00:00:00
abstract::We report the synthesis of a probe that permits the visualization by electron microscopy of acidic organelles in intact cells. This probe, 3-(2,4-dinitroanilino)-3'-amino-N-methyldipropylamine (DAMP), is a basic congener of dinitrophenol that readily diffuses into intact cells. Its primary and tertiary amino groups (a...
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.81.15.4838
更新日期:1984-08-01 00:00:00
abstract::Surfactant replacement therapy (SRT) involves instillation of a liquid-surfactant mixture directly into the lung airway tree. It is widely successful for treating surfactant deficiency in premature neonates who develop neonatal respiratory distress syndrome (NRDS). However, when applied to adults with acute respirator...
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.1504025112
更新日期:2015-07-28 00:00:00
abstract::The peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) is a transcriptional coactivator that controls expression of metabolic/energetic genes, programming cellular responses to nutrient and environmental adaptations such as fasting, cold, or exercise. Unlike other coactivators, PGC-1α contai...
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.2000643117
更新日期:2020-09-08 00:00:00
abstract::In order to study the mutagenic effects of site-specific, covalent modifications of biologically active DNA, we need host cells that are permissive for any type of mutation that might be produced in vivo from the modified DNA. Specifically, we require a general, in vivo complementation system for the bacteriophage phi...
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.75.2.774
更新日期:1978-02-01 00:00:00
abstract::Bacteriophage N4 minivirion RNA polymerase (mini-vRNAP), the RNA polymerase (RNAP) domain of vRNAP, is a member of the T7-like RNAP family. Mini-vRNAP recognizes promoters that comprise conserved sequences and a 3-base loop-5-base pair (bp) stem DNA hairpin structure on single-stranded templates. Here, we defined the ...
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.0610627104
更新日期:2007-04-24 00:00:00
abstract::Increased understanding of the precise molecular mechanisms involved in cell survival and cell death signaling pathways offers the promise of harnessing these molecules to eliminate cancer cells without damaging normal cells. Tyrosine kinase oncoproteins promote the genesis of leukemias through both increased cell pro...
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.1206551110
更新日期:2013-02-05 00:00:00
abstract::A specific fraction of chromosomal DNA from both yeast and a wide variety of other eukaryotes, but not from Escherichia coli, promotes high-frequency transformation in yeast. The plasmids containing these sequences are maintained as extra-chromosomal molecules in transformed cells. These results suggest that similar o...
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.78.5.3128
更新日期:1981-05-01 00:00:00
abstract::Brief learning experience (classical conditioning) induces frequency-specific receptive-field (RF) plasticity in the auditory cortex, characterized as increased response to the frequency of the conditioned stimulus and decreased responses to most other frequencies, including the pretraining best frequency. This experi...
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.90.6.2394
更新日期:1993-03-15 00:00:00
abstract::Transforming growth factor (TGF)-beta plays a pivotal role in regulation of progression of cancer through effects on tumor microenvironment as well as on cancer cells. TGF-beta inhibitors have recently been shown to prevent the growth and metastasis of certain cancers. However, there may be adverse effects caused by 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.0611660104
更新日期:2007-02-27 00:00:00
abstract::It is generally accepted that adult human bone marrow-derived mesenchymal stromal cells (hMSCs) are default committed toward osteogenesis. Even when induced to chondrogenesis, hMSCs typically form hypertrophic cartilage that undergoes endochondral ossification. Because embryonic mesenchyme is obviously competent to ge...
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.1720658115
更新日期:2018-05-01 00:00:00
abstract::Sets of Burkitt lymphoma lines and Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) derived from the same individuals were compared for sensitivity to cytotoxic T-lymphocyte (CTL) clones. Major histocompatibility complex class I antigen-restricted CTL clones were generated by stimulating the lymph...
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.83.15.5620
更新日期:1986-08-01 00:00:00
abstract::Near infrared diffuse optical spectroscopy and diffuse optical imaging are promising methods that eventually may enhance or replace existing technologies for breast cancer screening and diagnosis. These techniques are based on highly sensitive, quantitative measurements of optical and functional contrast between healt...
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.071511098
更新日期:2001-04-10 00:00:00
abstract::The carbon budget and dynamics of the Earth's interior, including the core, are currently very poorly understood. Diamond-bearing, mantle-derived rocks show a very well defined peak at δ(13)C ≈ -5 ± 3‰ with a very broad distribution to lower values (∼-40‰). The processes that have produced the wide δ(13)C distribution...
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.1401782112
更新日期:2015-01-06 00:00:00
abstract::The swelling of secretory vesicles has been implicated in exocytosis, but the underlying mechanism of vesicle swelling remains largely unknown. Zymogen granules (ZGs), the membrane-bound secretory vesicles in exocrine pancreas, swell in response to GTP mediated by a G(alpha)i3 protein. Evidence is presented here that ...
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.072083499
更新日期:2002-04-02 00:00:00
abstract::Diabetes mellitus is characterized by either the inability to produce insulin (type 1 diabetes) or as insensitivity to insulin secreted by the body (type 2 diabetes). In either case, the body is unable to move blood glucose efficiently across cell membranes to be used. This leads to a variety of local and systemic det...
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.1007884107
更新日期:2010-07-27 00:00:00
abstract::Lithium-air batteries have captured worldwide attention due to their highest energy density among the chemical batteries. To provide continuous oxygen channels, here, we synthesized hierarchical mesoporous perovskite La(0.5)Sr(0.5)CoO(2.91) (LSCO) nanowires. We tested the intrinsic oxygen reduction reaction (ORR) 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.1210315109
更新日期:2012-11-27 00:00:00
abstract::Activator 1 (A1; also called replication factor C), in conjunction with proliferating-cell nuclear antigen (PCNA), is essential for the elongation of primed DNA templates by DNA polymerases delta and epsilon. A1 contains five distinct subunits of 145, 40, 38, 37, and 36.5 kDa. Here we describe the isolation, sequence,...
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.89.7.2516
更新日期:1992-04-01 00:00:00
abstract::Berninamycin is a member of the pyridine-containing thiopeptide class of antibiotics that undergoes massive posttranslational modifications from ribosomally generated preproteins. Berninamycin has a 2-oxazolyl-3-thiazolyl-pyridine core embedded in a 35-atom macrocycle rather than typical trithiazolylpyridine cores emb...
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.1307111110
更新日期:2013-05-21 00:00:00
abstract::A 90-kDa surface glycoprotein was previously isolated and shown to be required for infection by the "major" group of human rhinovirus (HRV) serotypes. In the present work, the amino acid sequence of the receptor protein was obtained from CNBr and tryptic peptides. Using degenerate oligonucleotides predicted from the 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.86.13.4907
更新日期:1989-07-01 00:00:00
abstract::Time-resolved optical measurements encompassing the femtoseconds to seconds time scales have been used to investigate Rhodobacter capsulatus reaction centers (RCs) in which the histidine residue at position 200 on the M polypeptide has been changed to a leucine by site-directed mutagenesis. The HisM200----Leu RC, whic...
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.85.20.7562
更新日期:1988-10-01 00:00:00
abstract::Normal monkeys and monkeys with lesions of the hippocampal formation and adjacent cortex (the H+ lesion) were trained on the delayed nonmatching to sample (DNMS) task with a delay of 0.5 s between the sample and the choice. The animals with H+ lesions learned the task normally at this short delay and also exhibited 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.91.12.5637
更新日期:1994-06-07 00:00:00
abstract::cDNAs made from polyadenylylated RNAs of the mouse lens were cloned by the G.C tailing procedure in the bacterial plasmid pBR322. Four recombinant DNAs containing gamma-crystallin sequences were identified by hybrid selection and translation. Sequence analysis of the in vivo-labeled gamma-crystallin polypeptides that ...
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.79.9.2783
更新日期:1982-05-01 00:00:00
abstract::The effect of plasmin-derived fibrinogen fragments on the biosynthesis of fibrinogen was investigated in cultured monolayers of rat hepatocytes. Incubating the cells with several concentrations of either fibrinogen or fibrin fragment D or E had no effect on the synthesis and secretion of fibrinogen by these cells. How...
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.79.5.1530
更新日期:1982-03-01 00:00:00
abstract::Members of the transforming growth factor-β superfamily play essential roles in various aspects of embryonic development and physiological organ function. Among them, bone morphogenetic protein (BMP) 9 and BMP10 regulate embryonic vascular development by activating their endothelial receptor ALK1 (activin receptor-lik...
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.1207210109
更新日期:2012-07-24 00:00:00