Abstract:
:A family of nanoscale-sized supramolecular cage compounds with a polyhedral framework is prepared by self-assembly from tritopic building blocks and rectangular corner units via noncovalent coordination interactions. These highly symmetrical cage compounds are described as face-directed, self-assembled truncated tetrahedra with T(d) symmetry.
journal_name
Proc Natl Acad Sci U S Aauthors
Leininger S,Fan J,Schmitz M,Stang PJdoi
10.1073/pnas.030264697keywords:
subject
Has Abstractpub_date
2000-02-15 00:00:00pages
1380-4issue
4eissn
0027-8424issn
1091-6490pii
030264697journal_volume
97pub_type
杂志文章abstract::We use stable isotope ratios in feces of wild mountain gorillas (Gorilla beringei) to test the hypothesis that diet shifts within a single year, as measured by dry mass intake, can be recovered. Isotopic separation of staple foods indicates that intraannual changes in the isotopic composition of feces reflect shifts i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1215782109
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abstract::We have previously linked aging, carcinogenesis, and de novo methylation within the promoter of the estrogen receptor (ER) gene in human colon. We now examine the dynamics of this process for the imprinted gene for insulin-like growth factor II (IGF2). In young individuals, the P2-4 promoters of IGF2 are methylated ex...
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.93.21.11757
更新日期:1996-10-15 00:00:00
abstract::To enable discovery of serum antibodies indicative of disease and simultaneously develop reagents suitable for diagnosis, in vitro directed evolution was applied to identify consensus peptides recognized by patients' serum antibodies. Bacterial cell-displayed peptide libraries were quantitatively screened for binders ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1314792110
更新日期:2013-11-26 00:00:00
abstract::Hypercholesterolemia, high serum cholesterol in the form of LDL, is a major risk factor for atherosclerosis. LDL is mostly degraded in the liver after its cellular internalization with the LDL receptor (LDLR). This clathrin-mediated endocytosis depends on the protein autosomal recessive hypercholesterolemia (ARH), whi...
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.1114128109
更新日期:2012-05-01 00:00:00
abstract::The mechanisms that regulate insulin secretion were investigated using capacitance measurements of exocytosis in single beta cells maintained in tissue culture. Exocytosis was stimulated by voltage-clamp depolarizations to activate the voltage-dependent Ca2+ channels that mediate Ca2+ influx into the beta cell. Under ...
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.91.10.4343
更新日期:1994-05-10 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::We measured the M-N transition of wild-type bacteriorhodopsin (pH 9, 10 degrees C) by time-resolved x-ray diffraction study at SPring8 BL45XU-A. We confirmed the accumulation of M and N intermediates by absorbance measurements, and we found that the time resolution of x-ray diffraction experiments (244 ms) was suffici...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.260504897
更新日期:2000-12-19 00:00:00
abstract::The role of geographic isolation in marine microbial speciation is hotly debated because of the high dispersal potential and large population sizes of planktonic microorganisms and the apparent lack of strong dispersal barriers in the open sea. Here, we show that gene flow between distant populations of the globally 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.1001380107
更新日期:2010-07-20 00:00:00
abstract::High levels of D-serine occur in mammalian brain, where it appears to be an endogenous ligand of the glycine site of N-methyl-D-aspartate receptors. In glial cultures of rat cerebral cortex, D-serine is enriched in type II astrocytes and is released upon stimulation with agonists of non-N-methyl-D-aspartate glutamate ...
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.96.2.721
更新日期:1999-01-19 00:00:00
abstract::We find that histidine residues in proteins are major targets for reaction with the lipid peroxidation product 4-hydroxynon-2-enal (HNE). Reaction of insulin (which contains no sulfhydryl groups) with HNE leads to the generation of HNE-protein adducts, which are converted to radioactive derivatives upon subsequent tre...
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.89.10.4544
更新日期:1992-05-15 00:00:00
abstract::A cyclophilin (CyP) purified to homogeneity from the polycentric anaerobic rumen fungus Orpinomyces sp. strain PC-2 had a molecular mass of 20.5 kDa and a pI of 8.1. The protein catalyzed the isomerization of the prolyl peptide bond of N-succinyl-Ala-Ala-(cis,trans)-Pro-Phe p-nitroanilide with a kcat/Km value of 9.3 x...
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.92.7.2587
更新日期:1995-03-28 00:00:00
abstract::The identification and targeting of key molecular drivers of melanoma and breast and lung cancer have substantially improved their therapy. However, subtypes of each of these three common, lethal solid tumors lack identified molecular drivers, and are thus not amenable to targeted therapies. Here we show that pleckstr...
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.1804779115
更新日期:2018-06-19 00:00:00
abstract::Chaperones of the Hsp70 family bind to unfolded or partially folded polypeptides to facilitate many cellular processes. ATP hydrolysis and substrate binding, the two key molecular activities of this chaperone, are modulated by the cochaperone DnaJ. By using both genetic and biochemical approaches, we provide evidence ...
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.95.26.15223
更新日期:1998-12-22 00:00:00
abstract::Techniques of fluorescence and ion microscopies were combined to study the free [Ca2+] and total Ca in NIH 3T3 fibroblast and L6 rat myoblast cells. Free Ca2+ measurements with the Ca2+ indicator fura-2 and digital imaging reveal an inhomogeneous distribution of free cytoplasmic Ca2+ in both cell lines. Fura-2 also re...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.86.6.1870
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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.2004945117
更新日期:2020-06-02 00:00:00
abstract::Biological carbon fixation is limited by the supply of Fe in vast regions of the global ocean. Dissolved Fe in seawater is primarily sourced from continental mineral dust, submarine hydrothermalism, and sediment dissolution along continental margins. However, the relative contributions of these three sources to the Fe...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Many thylakoid lumen proteins are synthesized outside the chloroplast as larger molecular weight precursors and then processed to their mature size during transport to the lumenal space. We have examined the post-translational processing of thylakoid lumen proteins in vivo by pulse-radiolabeling experiments with Chlam...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2017-05-16 00:00:00
abstract::For almost a century, alcohols have been thought to produce their effects by actions on the membrane lipids of central nervous system neurons--the well known "lipid theory" of alcohol action. The rationale for this theory is the correlation of potency with oil/water or membrane/buffer partition coefficient. Although a...
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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.84.17.6272
更新日期:1987-09-01 00:00:00
abstract::Tropical forest degradation emits carbon at a rate of approximately 0.5 Pgxy(-1), reduces biodiversity, and facilitates forest clearance. Understanding degradation drivers and patterns is therefore crucial to managing forests to mitigate climate change and reduce biodiversity loss. Putative patterns of degradation aff...
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.0914471107
更新日期:2010-08-17 00:00:00
abstract::To study the role of low-abundance, embryonic muscle-specific gene transcripts, we have developed a method to screen cDNA clones from embryonic muscle for such sequences. The protocol involves two stages: first, partial enrichment for cDNA clones carrying possible embryo-specific sequences by selecting clones of low-a...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.77.8.4519
更新日期:1980-08-01 00:00:00
abstract::We have developed an approach for deriving and characterizing antigen-receptor (CD3/Ti) signal-transduction mutants. This strategy combines receptor-mediated growth inhibition and fluorescence-activated cell sorting with the Ca2+-indicator indo-1. Despite the expression of structurally normal CD3/Ti complexes, one suc...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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abstract::The central nervous system both influences and is influenced by the gastrointestinal system. Most research on this gut-brain connection has focused on how ascending signals from the gut and its microbiome alter brain function. Less attention has focused on how descending signals from the central nervous system alter g...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2020-06-09 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.0800406105
更新日期:2008-07-08 00:00:00
abstract::Some monocytes normally take up residence in tissues as sessile macrophages, but others differentiate into migratory cells resembling dendritic cells that emigrate to lymph nodes. In an in vitro model of a vessel wall, lipid mediators lysophosphatidic acid and platelet-activating factor, whose signals are implicated i...
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.0403259101
更新日期:2004-08-10 00:00:00
abstract::Myosin X (MyoX), encoded by Myo10, is a representative member of the MyTH4-FERM domain-containing myosins, and this family of unconventional myosins shares common functions in promoting formation of filopodia/stereocilia structures in many cell types with unknown mechanisms. Here, we present the structure of the MyoX ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1016567108
更新日期:2011-03-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1413170111
更新日期:2014-11-11 00:00:00