Abstract:
:After treatment with nitrite, Japanese soy sauce was strongly mutagenic to Salmonella typhimurium TA100 without S9 mixture. Two precursors of the mutagen were isolated from Japanese soy sauce, and these were identified as (-)-(1S,3S)-1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid [(-)-(1S,3S)-MTCA] and its stereoisomer (-)-(1R,3S)-MTCA. After treatment with nitrite, 1-mg samples of these compounds induced 17,400 and 13,000 revertants of TA100, respectively, without S9 mixture. Quantitative analysis of various kinds of soy sauces produced in Japan showed the presence of 82-678 micrograms of MTCA per ml. The mutagenicities of these compounds with nitrite accounted for 16-61% of the total mutagenicity of soy sauce with nitrite. Most soy sauces produced in the United States were less mutagenic than those produced in Japan and little, if any, of these two precursors of the mutagen was found in them. A major reaction product of (-)-(1S,3S)-MTCA and nitrite was a compound having a nitroso substitution at position N-2, but this compound was not mutagenic. Thus, the mutagen(s) formed from (-)-(1S,3S)-MTCA and nitrite was a minor product(s), and its specific mutagenic activity must be very high.
journal_name
Proc Natl Acad Sci U S Aauthors
Wakabayashi K,Ochiai M,Saitô H,Tsuda M,Suwa Y,Nagao M,Sugimura Tdoi
10.1073/pnas.80.10.2912subject
Has Abstractpub_date
1983-05-01 00:00:00pages
2912-6issue
10eissn
0027-8424issn
1091-6490journal_volume
80pub_type
杂志文章abstract::We have designed three zinc-finger proteins with different DNA binding specificities. The design strategy combines a consensus zinc-finger framework sequence with previously characterized recognition regions such that the specificity of each protein is predictable. The first protein consists of three identical zinc fi...
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.90.6.2256
更新日期:1993-03-15 00:00:00
abstract::Mathematical models have been developed to explore the population dynamics of viral diseases among wildlife. However, assessing the predictions stemming from these models with wildlife databases adequate in size and temporal duration is uncommon. An epizootic of raccoon rabies that began in the mid-Atlantic region of ...
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.240326697
更新日期:2000-12-05 00:00:00
abstract::Silencing of multiple cancer-related genes is associated with de novo methylation of linked CpG islands. Additionally, bivalent histone modification profiles characterized by the juxtaposition of active and inactive histone marks have been observed in genes that become hypermethylated in cancer. It is unknown how thes...
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.0810133105
更新日期:2008-12-16 00:00:00
abstract::Visual awareness has been proposed to depend on recurrent processing in early visual cortex areas including the primary visual cortex (V1). Here, we address this hypothesis with high spatiotemporal resolution magnetoencephalographic recordings in subjects performing a substitution masking paradigm. Neural activity ref...
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.0801999105
更新日期:2008-06-24 00:00:00
abstract::Adults and older children are more likely to punish a wrongdoer for a moral transgression when the victim belongs to their group. Building on these results, in violation-of-expectation experiments (n = 198), we examined whether 2.5-year-old toddlers (Exps. 1 and 2) and 1-year-old infants (Exps. 3 and 4) would selectiv...
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.1817849116
更新日期:2019-03-26 00:00:00
abstract::Metabolic, infectious, and tumor cell-intrinsic noxae can all evoke the endoplasmic reticulum (ER) stress response in tumor cells, which is critical for tumor cell growth and cancer progression. Evidence exists that the ER stress response can drive a proinflammatory program in tumor cells and macrophages but, to our k...
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.1008942108
更新日期:2011-04-19 00:00:00
abstract::We used positron emission tomography (PET) to examine the role of the hippocampal formation in implicit and explicit memory. Human volunteers studied a list of familiar words, and then they either provided the first word that came to mind in response to three-letter cues (implicit memory) or tried to recall studied wo...
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.93.1.321
更新日期:1996-01-09 00:00:00
abstract::The ability to integrate visual information over space is a fundamental component of human pattern vision. Regardless of whether it is for detecting luminance contrast or for recognizing objects in a cluttered scene, the position of the target in the visual field governs the size of a window within which visual inform...
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.1817076116
更新日期:2019-02-26 00:00:00
abstract::Memory stretches over a lifetime. In controlled laboratory settings, the hippocampus and other medial temporal lobe brain structures have been shown to represent space and time on the scale of meters and seconds. It remains unclear whether the hippocampus also represents space and time over the longer scales necessary...
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.1507104112
更新日期:2015-09-01 00:00:00
abstract::A segment of DNA containing cya, the gene for adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1], has been isolated from Salmonella typhimurium. The phage lambda gt4 was used as a cloning vector and adenylate cyclase-positive hybrid phages were isolated that complemented adenylate cyclase-negative bac...
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.78.8.4684
更新日期:1981-08-01 00:00:00
abstract::Collagen fibrils can exceed thousands of microns in length and are therefore the longest, largest, and most size-pleomorphic protein polymers in vertebrates; thus, knowing how cells transport collagen fibrils is essential for a more complete understanding of protein transport and its role in tissue morphogenesis. Here...
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.1314348110
更新日期:2013-12-03 00:00:00
abstract::Escherichia coli lipopolysaccharide (LPS)-induced nitrate biosynthesis was studied in LPS-sensitive C3H/He and LPS-resistant C3H/HeJ mice. Intraperitoneal injection of 15 micrograms of LPS led to a temporary 5- to 6-fold increase in blood nitrate concentration in the C3H/He strain. Levels of nitrate excreted in the ur...
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.82.22.7738
更新日期:1985-11-01 00:00:00
abstract::Iron is an essential nutrient for the survival of most organisms and has played a central role in the virulence of many infectious disease pathogens. Mycobacterial IdeR is an iron-dependent repressor that shows 80% identity in the functional domains with its corynebacterial homologue, DtxR (diphtheria toxin repressor)...
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.96.22.12844
更新日期:1999-10-26 00:00:00
abstract::The mammalian protein ZnT3 resides on synaptic vesicle membranes of zinc-containing neurons, suggesting its possible role in vesicular zinc transport. We show here that histochemically reactive zinc, corresponding to the zinc found within synaptic vesicles, was undetectable in the brains of mice with targeted disrupti...
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.96.4.1716
更新日期:1999-02-16 00:00:00
abstract::We show that it is possible to direct particles entrained in a fluid along trajectories much like rays of light in classical optics. A microstructured, asymmetric post array forms the core hydrodynamic element and is used as a building block to construct microfluidic metamaterials and to demonstrate refractive, focusi...
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.0712398105
更新日期:2008-05-27 00:00:00
abstract::The neural pathway that governs an escape response of Drosophila to sudden changes in light intensity can be artificially induced by electrical stimulation of the brain and monitored by electrical recording from the effector muscles. We have refined previous work in this system to permit reliable ascertainment of two ...
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.93.19.10446
更新日期:1996-09-17 00:00:00
abstract::The transcription factors that act in hepatocyte-specific gene expression include proteins that are present mainly in liver cells (HNF-1/LFB1, C/EBP, HNF-3, HNF-4) (HNF, hepatocyte nuclear factor; C/EBP, rat enhancer binding protein) and proteins that are widely distributed (AP-1, NF-1, NF-Y/ACF). We show here that 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.88.9.3807
更新日期:1991-05-01 00:00:00
abstract::Zachariae Isstrøm (ZI) and Nioghalvfjerdsfjorden (79N) are marine-terminating glaciers in northeast Greenland that hold an ice volume equivalent to a 1.1-m global sea level rise. ZI lost its floating ice shelf, sped up, retreated at 650 m/y, and experienced a 5-gigaton/y mass loss. Glacier 79N has been more stable des...
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.2015483118
更新日期:2021-01-12 00:00:00
abstract::Parathyroid hormone (PTH) is central to calcium homeostasis and bone maintenance in vertebrates, and as such it has been used for treating osteoporosis. It acts primarily by binding to its receptor, PTH1R, a member of the class B G protein-coupled receptor (GPCR) family that also includes receptors for glucagon, calci...
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.0801027105
更新日期:2008-04-01 00:00:00
abstract::During the past several decades, numerous reports from disparate geographical areas have documented an increased frequency of "bleaching" in reef-forming corals. The phenomenon, triggered by increased sea surface temperatures, occurs when the cnidarian hosts digest and/or expel their intracellular, photosynthetic dino...
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.1106924108
更新日期:2011-06-14 00:00:00
abstract::Mammalian DAI (DNA-dependent activator of IFN-regulatory factors), an activator of the innate immune response, senses cytosolic DNA by using 2 N-terminal Z-DNA binding domains (ZBDs) and a third putative DNA binding domain located next to the second ZBD. Compared with other previously known ZBDs, the second ZBD of hum...
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.0810463106
更新日期:2008-12-30 00:00:00
abstract::The interaction of homogeneous preparations of mouse submandibular gland nerve growth factor (NGF) with the classical complement pathway was studied. NGF was found to be capable of carrying out the enzyme activities of the first component (C1-) of the classical complement pathway (i.e., the cleavage of zymogen C4 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.79.8.2519
更新日期:1982-04-01 00:00:00
abstract::The mutation spectrum induced by the widely used antitumor drug cis-diamminedichloroplatinum(II) (cis-DDP) showed that cisDDP[d(ApG)] adducts, although they account for only 25% of the lesions formed, are approximately 5 times more mutagenic than the major GG adduct. We report the construction of vectors bearing a sin...
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.87.16.6087
更新日期:1990-08-01 00:00:00
abstract::The paradigm of bacterial quorum sensing (QS), which mediates cell-density-dependent gene expression, usually has been studied in high-cell-density planktonic liquid cultures or in biofilms in which signal concentrations accumulate to sufficiently high levels to induce QS. Presumably under conditions with restricted d...
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.0711723105
更新日期:2008-02-26 00:00:00
abstract::The pH gradient (delta pH) across the membrane of bovine neurohypophysial granules was estimated by using the [14C]methylamine partition technique. The granule membrane showed high permeability to sugars such as sucrose or sorbitol and to cations. Granules suspended in sucrose medium showed an acidic internal delta pH...
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.79.2.476
更新日期:1982-01-01 00:00:00
abstract::This article presents an agent-based computational model of civil violence. Two variants of the civil violence model are presented. In the first a central authority seeks to suppress decentralized rebellion. In the second a central authority seeks to suppress communal violence between two warring ethnic groups. ...
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.092080199
更新日期:2002-05-14 00:00:00
abstract::Epilepsy, a disease characterized by abnormal brain activity, is a disabling and potentially life-threatening condition for nearly 1% of the world population. Unfortunately, modulation of brain excitability using available antiepileptic drugs can have serious side effects, especially in the developing brain, and some ...
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.0900141106
更新日期:2009-09-08 00:00:00
abstract::Xenopus oocytes express a gene encoding bovine rhodopsin as well as its SP6 RNA polymerase-derived transcripts and total retinal mRNA. The opsin produced is in unglycosylated (30 kDa) and two glycosylated (35 kDa and 41 kDa) forms. Incubation of the cells expressing the above proteins with 11-cis-retinal generates rho...
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.85.21.7917
更新日期:1988-11-01 00:00:00
abstract::In all but the poorest countries of South Asia and Africa, the supply and quality of food will rise to meet the demand. Biotechnology, accelerated by genomics, will create wealth for both producers and consumers by reducing the cost and increasing the quality of food. Famine and malnutrition in the poorest countries m...
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.95.5.1986
更新日期:1998-03-03 00:00:00
abstract::Vibrational modes in mechanical resonators provide a promising candidate to interface and manipulate classical and quantum information. The observation of coherent dynamics between distant mechanical resonators can be a key step toward scalable phonon-based applications. Here we report tunable coherent phonon dynamics...
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.1916978117
更新日期:2020-03-17 00:00:00