Abstract:
:We previously reported that long-term cyclic estrogen (E) treatment reverses age-related impairment of cognitive function mediated by the dorsolateral prefrontal cortex (dlPFC) in ovariectomized (OVX) female rhesus monkeys, and that E induces a corresponding increase in spine density in layer III dlPFC pyramidal neurons. We have now investigated the effects of the same E treatment in young adult females. In contrast to the results for aged monkeys, E treatment failed to enhance dlPFC-dependent task performance relative to vehicle control values (group young OVX+Veh) but nonetheless led to a robust increase in spine density. This response was accompanied by a decline in dendritic length, however, such that the total number of spines per neuron was equivalent in young OVX+Veh and OVX+E groups. Robust effects of chronological age, independent of ovarian hormone status, were also observed, comprising significant age-related declines in dendritic length and spine density, with a preferential decrease in small spines in the aged groups. Notably, the spine effects were partially reversed by cyclic E administration, although young OVX+Veh monkeys still had a higher complement of small spines than did aged E treated monkeys. In summary, layer III pyramidal neurons in the dlPFC are sensitive to ovarian hormone status in both young and aged monkeys, but these effects are not entirely equivalent across age groups. The results also suggest that the cognitive benefit of E treatment in aged monkeys is mediated by enabling synaptic plasticity through a cyclical increase in small, highly plastic dendritic spines in the primate dlPFC.
journal_name
Proc Natl Acad Sci U S Aauthors
Hao J,Rapp PR,Janssen WG,Lou W,Lasley BL,Hof PR,Morrison JHdoi
10.1073/pnas.0704757104subject
Has Abstractpub_date
2007-07-03 00:00:00pages
11465-70issue
27eissn
0027-8424issn
1091-6490pii
0704757104journal_volume
104pub_type
杂志文章abstract::A convenient technique for the partial purification of large quantities of functional, poly(adenylic acid)-rich mRNA is described. The method depends upon annealing poly(adenylic acid)-rich mRNA to oligothymidylic acid-cellulose columns and its elution with buffers of low ionic strength. Biologically active rabbit glo...
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.69.6.1408
更新日期:1972-06-01 00:00:00
abstract::Micron-scale robots require systems that can morph into arbitrary target configurations controlled by external agents such as heat, light, electricity, and chemical environment. Achieving this behavior using conventional approaches is challenging because the available materials at these scales are not programmable 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.1922635117
更新日期:2020-04-21 00:00:00
abstract::Serine is the only amino acid that is encoded by two disjoint codon sets so that a tandem substitution of two nucleotides is required to switch between the two sets. Previously published evidence suggests that, for the most evolutionarily conserved serines, the codon set switch occurs by simultaneous substitution of 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.1615832113
更新日期:2016-11-15 00:00:00
abstract::Nanos (Nos) is an evolutionarily conserved protein essential for the survival of primordial germ cells. In Drosophila, maternal Nos partitions into pole cells and suppresses apoptosis to permit proper germ-line development. However, how this critical event is regulated by Nos has remained elusive. Here, we report 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.0610052104
更新日期:2007-05-01 00:00:00
abstract::An intense investigation of possible non-Fermi liquid states of matter has been inspired by two of the most intriguing phenomena discovered in the past quarter century, namely, high-temperature superconductivity and the fractional quantum Hall effect. Despite enormous conceptual strides, these two fields have 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.0902901106
更新日期:2009-06-09 00:00:00
abstract::Corazonin is a highly conserved neuropeptide hormone of wide-spread occurrence in insects yet is associated with no universally recognized function. After discovery of the corazonin receptor in Drosophila, we identified its ortholog in the moth, Manduca sexta, as a prelude to physiological studies. The corazonin recep...
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.0305291101
更新日期:2004-04-27 00:00:00
abstract::Investigations using the fruit fly Drosophila melanogaster have shown that the circadian clock gene period (Per) can influence behavioral responses to cocaine. Here we show that the mouse homologues of the Drosophila Per gene, mPer1 and mPer2, modulate cocaine sensitization and reward, two phenomena extensively studie...
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.142039099
更新日期:2002-06-25 00:00:00
abstract::The template for transcription and replication of negative-stranded RNA viruses is a ribonucleoprotein structure, the nucleocapsid. We have developed a system that supports assembly of the negative-stranded RNA genome of a defective interfering (DI) particle of vesicular stomatitis virus (VSV) into a nucleocapsid in v...
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.85.20.7511
更新日期:1988-10-01 00:00:00
abstract::Inorganic polyphosphate (polyP) is composed of linear chains of phosphate groups linked by high-energy phosphoanhydride bonds. However, this simple, ubiquitous molecule remains poorly understood. The use of nonstandardized analytical methods has contributed to this lack of clarity. By using improved polyacrylamide gel...
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.1519440113
更新日期:2016-01-26 00:00:00
abstract::Specific viral transformation rather than cell selection can explain the previously observed increase in the proportion of type III procollagen compared to type I procollagen in BALB 3T3 cells transformed by Kirsten murine sarcoma virus (Ki-MSV). Two subclones of BALB 3T3 A31 were productively infected with with a tem...
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.78.10.6028
更新日期:1981-10-01 00:00:00
abstract::Upon release from the anther, pollen grains of angiosperm flowers are exposed to a dry environment and dehydrate. To survive this process, pollen grains possess a variety of physiological and structural adaptations. Perhaps the most striking of these adaptations is the ability of the pollen wall to fold onto itself to...
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.0911223107
更新日期:2010-04-27 00:00:00
abstract::The DNA in chromatin of isolated thymus nuclei, and in two different preparations of deoxyribonucleoprotein extracted from chromatin, has been digested with DNase. By variation of the time of reaction and the concentration of enzyme, and by comparison of the action of the enzyme on (protein-free) DNA with its action 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.68.12.2945
更新日期:1971-12-01 00:00:00
abstract::Nitroxyl anion (HNONO(-)), the one-electron reduced form of nitric oxide (NO), induces positive cardiac inotropy and selective venodilation in the normal in vivo circulation. Here we tested whether HNO/NO(-) augments systolic and diastolic function of failing hearts, and whether contrary to NO/nitrates such modulation...
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.0937302100
更新日期:2003-04-29 00:00:00
abstract::A study was undertaken to elucidate the molecular mechanisms by which glucocorticoids induce cleft palate in mice. It was hypothesized that a compound such as triamcinolone acetonide inhibits mRNA synthesis; that this results later in depressed protein synthesis; and that the latter is ultimately responsible for slowe...
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.67.2.779
更新日期:1970-10-01 00:00:00
abstract::Secretion of inflammatory mediators by rat mast cells (line RBL-2H3) was earlier shown to be inhibited upon clustering a membrane glycoprotein by monoclonal antibody G63. This glycoprotein, named mast cell function-associated antigen (MAFA), was also shown to interfere with the coupling cascade of the type 1 Fc epsilo...
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.92.20.9397
更新日期:1995-09-26 00:00:00
abstract::Lignocellulosic plant biomass is an attractive feedstock for the production of sustainable biofuels, but the commercialization of such products is hampered by the high costs of processing this material into fermentable sugars (saccharification). One approach to lowering these costs is to produce crops with cell walls ...
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.1414020111
更新日期:2014-10-07 00:00:00
abstract::Heparan sulfate regulates diverse cell-surface signaling events, and its roles in the development of the nervous system recently have been increasingly uncovered by studies using genetic models carrying mutations of genes encoding enzymes for its synthesis. On the other hand, the role of heparan sulfate in the physiol...
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.1117881109
更新日期:2012-03-27 00:00:00
abstract::Host-encoded factors play an important role in virus multiplication, acting in concert with virus-encoded factors. However, information regarding the host factors involved in this process is limited. Here we report the map-based cloning of an Arabidopsis thaliana gene, TOM1, which is necessary for the efficient multip...
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.170295097
更新日期:2000-08-29 00:00:00
abstract::We have shown that the silk fibroin gene from Bombyx mori is faithfully transcribed in an in vitro transcription system of the HeLa cell extract prepared by the method of Manley et al. [Manley, J. L., Fire, A., Cano, A., Sharp, P. A. & Gefter, M. L. (1980) Proc. Natl. Acad. Sci. USA 77, 3855-3859]. Using this system 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.78.8.4838
更新日期:1981-08-01 00:00:00
abstract::Hematopoietic stem/progenitor cells (HSPCs) possess the potentials of self-renewal, proliferation, and differentiation toward different lineages of blood cells. These cells not only play a primordial role in hematopoietic development but also have important clinical application. Characterization of the gene expression...
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.95.14.8175
更新日期:1998-07-07 00:00:00
abstract::Vesicles were constituted with glycophorin, the Sendai virus receptor of human erythrocytes, and loaded with calcein, a polar derivative of fluorescein, at self-quenching concentrations. On exposure to Sendai virus and mild hypo-osmotic stress, vesicles of the appropriate composition released a significant portion 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.80.6.1608
更新日期:1983-03-01 00:00:00
abstract::Copper is an essential micronutrient that plays a central role for a broad range of biological processes. Although there is compelling evidence that the intracellular milieu does not contain any free copper ions, the rapid kinetics of copper uptake and release suggests the presence of a labile intracellular copper poo...
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.0406547102
更新日期:2005-08-09 00:00:00
abstract::Hypoxia-inducible factor-1 (HIF-1) plays an essential role in tumor development and progression by regulating genes that are vital for proliferation, glycolysis, angiogenesis, and metastasis. To identify strategies of targeting the HIF-1 pathway, we screened a siRNA library against the entire druggable genome and a sm...
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.0706585104
更新日期:2008-01-08 00:00:00
abstract::A comprehensive mapping of interactions among Epstein-Barr virus (EBV) proteins and interactions of EBV proteins with human proteins should provide specific hypotheses and a broad perspective on EBV strategies for replication and persistence. Interactions of EBV proteins with each other and with human proteins were as...
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.0702332104
更新日期:2007-05-01 00:00:00
abstract::Gaseous HCl generated from a variety of sources is ubiquitous in both outdoor and indoor air. Oxides of nitrogen (NO(y)) are also globally distributed, because NO formed in combustion processes is oxidized to NO(2), HNO(3), N(2)O(5) and a variety of other nitrogen oxides during transport. Deposition of HCl and NO(y) 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.0904195106
更新日期:2009-08-18 00:00:00
abstract::The Met mutant of Drosophila melanogaster is highly resistant to juvenile hormone III (JH III) or its chemical analog, methoprene, an insect growth regulator. Five major mechanisms of insecticide resistance were examined in Met and susceptible Met+ flies. These two strains showed only minor differences when penetratio...
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.87.6.2072
更新日期:1990-03-01 00:00:00
abstract::Decision-making accuracy typically increases through collective integration of people's judgments into group decisions, a phenomenon known as the wisdom of crowds. For simple perceptual laboratory tasks, classic signal detection theory specifies the upper limit for collective integration benefits obtained by weighted ...
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.1610732114
更新日期:2017-05-23 00:00:00
abstract::The interaction of configurations, including all possible singly excited configurations, is incorporated into the calculation of oscillatory and rotatory intensities of simple nonplanar pi-electronic systems such as skewed butadiene and acrolein. The results are discussed in terms of the reliability of the (self-consi...
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.67.4.1727
更新日期:1970-12-01 00:00:00
abstract::The molecular basis for the absence of anthocyanins and proanthocyanidins in four independent sodium azide-induced ant18 mutants of barley was examined by sequencing the gene encoding dihydroflavonol 4-reductase in these mutants. Sodium azide generated 21 base substitutions, which corresponds to 0.17% of the 12,704 nu...
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.90.17.8043
更新日期:1993-09-01 00:00:00
abstract::Illumination of a system consisting of a vertical tube containing an unstirred homogeneous suspension of thylakoids in an imposed linear concentration gradient of an electron acceptor, 2,6-dichloroindophenol, gave rise to a one-dimensional banded pattern of the acceptor that evolved in a time-dependent manner. The spa...
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.86.2.516
更新日期:1989-01-01 00:00:00