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81.
Beatris Mastelic Nathalie Garçon Giuseppe Del Giudice Hana Golding Marion Gruber Pieter Neels Bernard Fritzell 《Biologicals》2013,41(6):458-468
Vaccination represents one of the greatest public health triumphs; in part due to the effect of adjuvants that have been included in vaccine preparations to boost the immune responses through different mechanisms. Although a variety of novel adjuvants have been under development, only a limited number have been approved by regulatory authorities for human vaccines. This report reflects the conclusions of a group of scientists from academia, regulatory agencies and industry who attended a conference on the current state of the art in the adjuvant field. Held at the U.S. Pharmacopeial Convention (USP) in Rockville, Maryland, USA, from 18 to 19 April 2013 and organized by the International Association for Biologicals (IABS), the conference focused particularly on the future development of effective adjuvants and adjuvanted vaccines and on overcoming major hurdles, such as safety and immunogenicity assessment, as well as regulatory scrutiny. More information on the conference output can be found on the IABS website, http://www.iabs.org/. 相似文献
82.
Ambient noise interferes with the propagation of acoustic signals through the environment from sender to receiver. Over the past few centuries, urbanization and the development of busy transport networks have led to dramatic increases in the levels of ambient noise with which animal acoustic communications must compete. Here we show that urban European robins Erithacus rubecula, highly territorial birds reliant on vocal communication, reduce acoustic interference by singing during the night in areas that are noisy during the day. The effect of ambient light pollution, to which nocturnal singing in urban birds is frequently attributed, is much weaker than that of daytime noise. 相似文献
83.
Expression of the gap junction protein connexin43 in embryonic chick lens: Molecular cloning,ultrastructural localization,and post-translational phosphorylation 总被引:13,自引:0,他引:13
Linda S. Musil Eric C. Beyer Daniel A. Goodenough 《The Journal of membrane biology》1990,116(2):163-175
Summary Lens epithelial cells are physiologically coupled to each other and to the lens fibers by an extensive network of intercellular gap junctions. In the rat, the epithelial-epithelial junctions appear to contain connexin43, a member of the connexin family of gap junction proteins. Limitations on the use of rodent lenses for the study of gap junction formation and regulation led us to examine the expression of connexin43 in embryonic chick lenses. We report here that chick connexin43 is remarkably similar to its rat counterpart in primary amino acid sequence and in several key structural features as deduced by molecular cDNA cloning. The cross-reactivity of an anti-rat connexin43 serum with chick connexin43 permitted definitive immunocytochemical localization of chick connexin43 to lens epithelial gap junctional plaques and examination of the biosynthesis of connexin43 by metabolic radiolabeling and immunoprecipitation. We show that chick lens cells synthesize connexin43 as a single, 42-kD species that is efficiently posttranslationally converted to a 45-kD form. Metabolic labeling of connexin43 with32P-orthophosphate combined with dephosphorylation experiments reveals that this shift in apparent molecular weight is due solely to phosphorylation. These results indicate that embryonic chick lens is an appropriate system for the study of connexin43 biosynthesis and demonstrate for the first time that connexin43 is a phosphoprotein. 相似文献
84.
ANNA C. D. R. BARBOSA THAÍS C. CORRÊA FELIPE GALZERANI PEDRO M. GALETTI TERUMI HATANAKA 《Molecular ecology resources》2006,6(3):936-938
Prochilodus species inhabit the main river systems of South America and usually present commercial value to inland fishing. In the present study, we describe the isolation and characterization of 13 novel microsatellite loci in Prochilodus argenteus. The number of alleles per polymorphic locus varied from four to 22 and the observed heterozygosity ranged from 0.333 to 0.893. Additionally, cross‐species amplification was successful in two other Prochilodus species. These loci will be useful for studies of the population genetic structure in this fish group. 相似文献
85.
Group members present physical and physiological differences according to their age, sex or social status, which could generate
motivation differences among individuals during travel. In spite of these divergences of interest among individuals, the group
succeeds more often than not in making a collective decision about departure time and which direction to take. To reach a
consensus decision, animals should exchange information relating to characteristics of group movement through different communication
channels. The main purpose of this study is to understand the function of behaviour patterns displayed during movements of
white-faced capuchins (Cebus capucinus). We designed experiments in which we provoked collective movements involving a binary choice. During experiments, a video
camera recorded the behaviour of each capuchin, which enabled us to determine which individuals displayed a behavioural pattern
during travel and how this behaviour influenced the other group members. We found that looking backwards seemed to permit
the recruitment of group mates during collective movement. This behaviour also seemed to allow the quantification of the number
of followers, since the emitter modified its locomotion speed according to this number. In this preliminary study, we showed
that visual behaviour was used to recruit and monitor group mates during collective movements and provided information on
mechanisms involved in maintaining cohesion and coordination among group members during travel. 相似文献
86.
Gonçalo C. Cardoso João M. Abreu John Archer Angelica Crottini Paulo G. Mota 《Evolution; international journal of organic evolution》2020,74(6):1170-1185
The diversity and the motor performance of birdsongs can both be sexually selected. In wood warblers, most species with high motor performance sing a greater proportion of trills, presumably to advertise performance, and thus have lower syllable diversity. We tested if this trade-off between motor performance and syllable diversity extends to canaries, goldfinches and allies, a clade with much longer and more varied songs. We assembled a molecular phylogeny and inferred song motor performance based on the speed of frequency modulation either in trills or in within-song intervals. The two metrics of performance were positively, but only mildly, related across species. While performance evaluated in intervals had high phylogenetic signal, performance evaluated in trills changed independently of phylogeny and was constrained by body size. Species in densely vegetated habitats sang fewer trills, but did not differ in motor performance. Contrary to wood warblers, song motor performance did not predict the proportion of trilled syllables nor within-song syllable diversity, perhaps because large differences in the song duration of canaries, goldfinches and allies prevent trills from severely compromising syllable diversity. Opposed results in wood warblers and in these finches indicate the existence of clade-specific trade-offs in the evolution of birdsong. 相似文献
87.
Robbie IAnson Price Francisca Segers Amelia Berger Fabio S Nascimento Christoph Grüter 《动物学报(英文版)》2021,67(5):551
Social information is widely used in the animal kingdom and can be highly adaptive. In social insects, foragers can use social information to find food, avoid danger, or choose a new nest site. Copying others allows individuals to obtain information without having to sample the environment. When foragers communicate information they will often only advertise high-quality food sources, thereby filtering out less adaptive information. Stingless bees, a large pantropical group of highly eusocial bees, face intense inter- and intra-specific competition for limited resources, yet display disparate foraging strategies. Within the same environment there are species that communicate the location of food resources to nest-mates and species that do not. Our current understanding of why some species communicate foraging sites while others do not is limited. Studying freely foraging colonies of several co-existing stingless bee species in Brazil, we investigated if recruitment to specific food locations is linked to 1) the sugar content of forage, 2) the duration of foraging trips, and 3) the variation in activity of a colony from 1 day to another and the variation in activity in a species over a day. We found that, contrary to our expectations, species with recruitment communication did not return with higher quality forage than species that do not recruit nestmates. Furthermore, foragers from recruiting species did not have shorter foraging trip durations than those from weakly recruiting species. Given the intense inter- and intraspecific competition for resources in these environments, it may be that recruiting species favor food resources that can be monopolized by the colony rather than food sources that offer high-quality rewards. 相似文献
88.
89.
21世纪植物化学生态学前沿领域 总被引:32,自引:10,他引:32
植物和其它有机体通过次生物质为媒介的化学作用关系近年引入注目,其中植物的诱导化学防御,植物的化学通讯,植物次生物质和进化的关系,植物与人类的化学关系和海洋植物化学生态学是21世纪植物化学生态学值得关注的前沿领域。植物化学生态学前沿领域的进展将为实现21世纪的持续,发展是在生态安全条件下提高农业产量并达到对病虫草害的有效控制方面具有重要意义。 相似文献
90.
Interstitial cells of Cajal: mediators of communication between circular and longitudinal muscle layers of canine colon 总被引:3,自引:0,他引:3
Louis W. C. Liu Laura Farraway Irene Berezin J. D. Huizinga 《Cell and tissue research》1998,294(1):69-79
The network of interstitial cells of Cajal associated with Auerbach’s (myenteric) plexus in the canine colon was investigated
to determine its role in facilitating communication between circular and longitudinal muscle layers. Electrical coupling between
the muscle layers was demonstrated by propagating extracellularly evoked electrotonic pulses from circular muscle cells to
nearby longitudinal muscle cells. The likelihood of cytoplasmic continuity across Auerbach’s plexus was further demonstrated
by the ability of neurobiotin to spread between the interstitial cells and the circular and longitudinal muscle cells. Importantly,
direct neurobiotin spread between circular and longitudinal muscle cells was not observed even when they were in close proximity
as determined by confocal microscopy. When neurobiotin did spread across the two muscle layers, the intervening interstitial
cells were always neurobiotin-positive. In regions where circular and longitudinal muscle cells approach each other closely,
electron microscopy revealed the presence of close appositions between interstitial cells and smooth muscle cells. Gap junctions
between interstitial cells and smooth muscle cells of both layers, as judged by electron microscopy, were extremely rare.
Neither gap junctions nor close appositions were observed between longitudinal and circular muscle cells. The special arrangement
for electrotonic coupling across Auerbach’s plexus through interstitial cells of Cajal suggests controlled coupling between
the two muscle layers, explaining the preservation of their distinct electrical activities.
Received: 21 July 1995 / Accepted: 22 April 1998 相似文献