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This study investigated the specificity of dream content and its continuity with waking life. For each subject (125 men and 125 women, between the ages of 19 and 29 years), a dream and a waking episode were collected according to “the most recent dream” method (Hartmann, Elkin, & Garg, 1991), which was also applied to “a recent life episode.” Both kinds of narratives were analyzed through the application of the Hall–Van de Castle System (1966) and a typical content analysis (a compendium of the most important typical dream taxonomies). In dreams, typical situations involved the dreamer trying to perform some physical action, most frequently with difficulties in mastering the task. Affective relationships and hostile interactions with an enemy were shared by both narratives, but cognitive activities were uncommon in both cases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
Naviglio S Spina A Chiosi E Fusco A Illiano F Pagano M Romano M Senatore G Sorrentino A Sorvillo L Illiano G 《Journal of cellular biochemistry》2006,98(6):1584-1596
In order to elucidate how phosphate regulates cellular functions, we investigated the effects of inorganic phosphate (Pi) on adenylate cyclase (AC)/cyclic AMP (cAMP) axis. Here we describe that Pi treatment of human osteosarcoma U2OS cells results in a decrease of both intracellular cAMP levels and AC activity, and in a cell growth inhibition. The phosphate-triggered effects observed in U2OS cells are not a widespread phenomenon regarding all cell lines, since other cell lines screened respond differently to parallel Pi treatments. In U2OS cell line, the AC activity/cAMP downregulation is accompanied by significant variations in the levels of some membrane proteins belonging to the AC system. Remarkably, the above effects are blunted by pharmacological inhibition of sodium-dependent phosphate transport. Moreover, 8-Br-cAMP and other cAMP-elevating agents, such as IBMX and forskolin, interestingly, prevent the cell growth inhibition in response to phosphate. Our results enforce the increasing evidences of phosphate as a signaling molecule, identifying in U2OS cell line the AC/cAMP axis, as a novel-signaling pathway modulated by phosphate to ultimately affect cell growth. 相似文献
135.
Niccolò Fattorini Alessandra Costanzo Andrea Romano Diego Rubolini Stephen Baillie Franz Bairlein Fernando Spina Roberto Ambrosini 《Ecology letters》2023,26(7):1095-1107
Migratory connectivity, reflecting the extent by which migrants tend to maintain their reciprocal positions in seasonal ranges, can assist in the conservation and management of mobile species, yet relevant drivers remain unclear. Taking advantage of an exceptionally large (~150,000 individuals, 83 species) and more-than-a-century-long dataset of bird ringing encounters, we investigated eco-evolutionary drivers of migratory connectivity in both short- and long-distance Afro-Palearctic migratory birds. Connectivity was strongly associated with geographical proxies of migration costs and was weakly influenced by biological traits and phylogeny, suggesting the evolutionary lability of migratory behaviour. The large intraspecific variability in avian migration strategies, through which most species geographically split into distinct migratory populations, explained why most of them were significantly connected. By unravelling key determinants of migratory connectivity, our study improves knowledge about the resilience of avian migrants to ecological perturbations, providing a critical tool to inform transboundary conservation and management strategies at the population level. 相似文献
136.
Producer-cell modification of human immunodeficiency virus type 1: Nef is a virion protein. 总被引:7,自引:17,他引:7 下载免费PDF全文
M W Pandori N J Fitch H M Craig D D Richman C A Spina J C Guatelli 《Journal of virology》1996,70(7):4283-4290
Type 1 human immunodeficiency viruses encoding mutated nef reading frames are 10- to 30-fold less infectious than are isogenic viruses in which the nef gene is intact. This defect in infectivity causes nef-negative viruses to grow at an attenuated rate in vitro. To investigate the mechanism of Nef-mediated enhancement of viral growth rate and infectivity, a complementation analysis of nef mutant viruses was performed. To provide Nef in trans upon viral infection, a CEM derivative cell line (designated CLN) that expresses Nef under the control of the viral long terminal repeat was constructed. When nef-negative virus was grown in CLN cells, its growth rate was restored to wild-type levels. However, the output of nef-negative virus during the first 72 h after infection of CLN cells was not restored, suggesting that provision of Nef within the newly infected cell does not enhance the productivity of a nef-negative provirus. The genetically nef-negative virions produced by the CLN cells, however, were restored to wild-type levels of infectivity as measured in a syncytium formation assay in which CD4-expressing HeLa cells were targets. These trans-complemented, genetically nef-negative virions yielded wild-type levels of viral output following a single cycle of replication in primary CD4 T cells as well as in parental CEM cells. To define the determinants for producer cell modification of virions by Nef, the role of myristoylation was investigated. Virus that encodes a myristoylation-negative nef was as impaired in infectivity as was virus encoding a deleted nef gene. Because myristoylation is required for both membrane association of Nef and optimal viral infectivity, the possibility that Nef protein is included in the virion was investigated. Wild-type virions were purified by filtration and exclusion chromatography. A Western blot (immunoblot) of the eluate fractions revealed a correlation between peak Nef signal and peak levels of p24 antigen. Although virion-associated Nef was detected in part as the 27-kDa full-length protein, the majority of immunoreactive protein was detected as a 20-kDa isoform. nef-negative virus lacked both 27- and 20-kDa immunoreactive species. Production of wild-type virions in the presence of a specific inhibitor of the human immunodeficiency virus type 1 protease resulted in virions which contained only 27-kDa full-length Nef protein. These data indicate that Nef is a virion protein which is processed by the viral protease into a 20-kDa isoform within the virion particle. 相似文献
137.
Fernando Spina 《Journal of Ornithology》1990,131(2):177-178
Summary Complete summer moult in the Great Reed Warbler (Acrocephalus a. arundinaceus) is a rare phenomenon, and only two cases have so far been reported for Europe. In 5 years of summer ringing in Val Campotto, Northern Italy, 12 different individuals were found in complete moult. Only the two innermost primaries are generally renewed, with more advanced stages of moult involving up to 6 primaries, the tertials and the first secondaries. A single bird controlled in three subsequent years was always found at a similar degree of primary moult. 相似文献
138.
Multimeric soluble CD40 ligand and GITR ligand as adjuvants for human immunodeficiency virus DNA vaccines 总被引:3,自引:0,他引:3 下载免费PDF全文
Stone GW Barzee S Snarsky V Kee K Spina CA Yu XF Kornbluth RS 《Journal of virology》2006,80(4):1762-1772
For use in humans, human immunodeficiency virus (HIV) DNA vaccines may need to include immunostimulatory adjuvant molecules. CD40 ligand (CD40L), a member of the tumor necrosis factor (TNF) superfamily (TNFSF), is one candidate adjuvant, but it has been difficult to use because it is normally expressed as a trimeric membrane molecule. Soluble trimeric forms of CD40L have been produced, but in vitro data indicate that multimeric, many-trimer forms of soluble CD40L are more active. This multimerization requirement was evaluated in mice using plasmids that encoded either 1-trimer, 2-trimer, or 4-trimer soluble forms of CD40L. Fusion with the body of Acrp30 was used to produce the 2-trimer form, and fusion with the body of surfactant protein D was used to produce the 4-trimer form. Using plasmids for secreted HIV-1 antigens Gag and Env, soluble CD40L was active as an adjuvant in direct proportion to the valence of the trimers (1 < 2 < 4). These CD40L-augmented DNA vaccines elicited strong CD8(+) T-cell responses but did not elicit significant CD4(+) T-cell or antibody responses. To test the applicability of the multimeric fusion protein approach to other TNFSFs, a 4-trimer construct for the ligand of glucocorticoid-induced TNF family-related receptor (GITR) was also prepared. Multimeric soluble GITR ligand (GITRL) augmented the CD8(+) T-cell, CD4(+) T-cell, and antibody responses to DNA vaccination. In summary, multimeric CD40L and GITRL are new adjuvants for DNA vaccines. Plasmids for expressing multimeric TNFSF fusion proteins permit the rapid testing of TNFSF molecules in vivo. 相似文献
139.
Human peripheral blood leukocytes were exposed to either PWM or Con A mitogens. Cells activated by both these mitogens were able to depress proliferation in an MLC, and to inhibit the generation of spontaneous killer cell (SK) and induced T-cell cytotoxic activity. PWM-activated cells incubated in media for 48 hr were able to elaborate a soluble factor in vitro. This factor suppressed cytotoxicity, and was active only when present at the initiation of MLC cultures. In contrast, cells exposed to Con A were able to suppress immune responsiveness, but this population did not release a soluble factor which could inhibit cytotoxicity. PWM induction appears to be dependent on phagocytic cells, while Con A activation is less dependent on this adherent population. An enriched adherent cell population, stimulated with PWM, was able to suppress cytotoxicity. Thus, the PWM-stimulated system of suppression is mediated through a soluble factor and is dependent on adherent cells. 相似文献
140.
G. Spina P. Schiatti D. Selva L. Gallico A. Glässer 《Prostaglandins & other lipid mediators》1984,28(2):158-171
The gastric protection, diarrheogenic and arterial hypotensive effects of MDL-646, a PGE1 derivative, have been studied in rats. The compound administered p.o. or i.v. was able to inhibit the maroscopic damage to gastric mucosa produced by noxious stimuli (ethanol and indomethacin). In the stomach perfusion test with the anesthetized rat, intravenously administered MDL-646 reduced histamine- or pentagastrin-stimulated gastric secretion. After intraduodenal administration (i.d.) doses at least 40–50 times greater were necessary for an antisecretory effect. In conscious rats with chronic gastric fistulas, intragastrically administered (i.g.) MDL-646 affected both acid concentration and volume of unstimulated gastric secretion. In experimental models for gastric lesions, DML-646 was much more potent after oral (p.o.) (15–30 times) than after i.v. administration. (ED50 μg/kg: vs. alcohol lesions, 0.05 p.o. and 0.7 i.v.; vs. indomethacin ulcers, 7.0 p.o. and 195 i.v.). Our data would fit the hypothesis that it was a local effect on the gastric mucosa. The mechanism of this effect is not known. The supposed local activity coupled with the antisecretory effects and the good tolerability make it interesting to test MDL-646 as an anti-ulcer agent in man. 相似文献