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Review of experimental and observational evidence about various cestode infections of mammalian hosts revives hope for the development of an effective vaccine against adult intestinal tapeworms, the central protagonists in their transmission dynamics. As for Taenia solium, there are abundant immunological data regarding cysticercosis in humans and pigs, but information about human taeniasis is scarce. A single publication reporting protection against T. solium taeniasis by experimental primo infection and by vaccination of an experimental foster host, the immunocompetent female hamster, kindles the hope of a vaccine against the tapeworm to be used in humans, its only natural definitive host.  相似文献   
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For many years, fisheries management was based on optimizing yield and maintaining a target biomass, with little regard given to low-frequency environmental forcing. However, this policy was often unsuccessful. In the last two to three decades, fisheries science and management have undergone a shift towards balancing sustainable yield with conservation, with the goal of including ecosystem considerations in decision-making frameworks. Scientific understanding of low-frequency climate–ocean variability, which is manifested as ecosystem regime shifts and states, has led to attempts to incorporate these shifts and states into fisheries assessment and management. To date, operationalizing these attempts to provide tactical advice has met with limited success. We review efforts to incorporate regime shifts and states into the assessment and management of fisheries resources, propose directions for future investigation and outline a potential framework to include regime shifts and changes in ecosystem states into fisheries management.  相似文献   
4.
Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain) regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo.    相似文献   
5.
Nest site fidelity and serial polyandry were examined in lingcod, Ophiodon elongatus, a teleost fish in which the nest-guarding male parent invests more heavily in parental care than the elusive female parent. Lingcod parental and progeny genotypes were established for fish spawning on a 200 m(2) section of Snake Island reef, British Columbia in two successive years to evaluate male and female mate choice (monogamy or polygamy) and nest site reuse by the same parents (nest site fidelity) and/or different parents (nest site affinity). Thirteen nests (egg masses) guarded by nine males and 14 nests guarded by seven males were observed in 2002 and 2003, respectively. No female laid more than one nest per season or spawned in the study area in both years. In contrast, at least six (86%) and possibly all seven (100%) of the 2003 guardian males had been guardian or auxiliary males in 2002. Both nest site affinity and extreme male nest site fidelity were observed, with at least four males reusing the exact same nest site. Serial polyandry resulting from the high male and low female nest site fidelity is consistent with predictions based on a low female parental investment and high rate of progeny loss to predation and cannibalism. Male polygyny, achieved primarily by cuckoldry within seasons, was enhanced by the lack of female fidelity between seasons. Polygamy in both sexes of nest-tending marine fish may minimize reproductive skew and maximize genetic diversity within populations.  相似文献   
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Planta - Transgenic papaya callus lines expressing the components of the S3Pvac vaccine constitute a stable platform to produce an oral vaccine against cysticercosis caused by Taenia solium or T....  相似文献   
7.

Background

Cysticercosis and hydatidosis seriously affect human health and are responsible for considerable economic loss in animal husbandry in non-developed and developed countries. S3Pvac and EG95 are the only field trial-tested vaccine candidates against cysticercosis and hydatidosis, respectively. S3Pvac is composed of three peptides (KETc1, GK1 and KETc12), originally identified in a Taenia crassiceps cDNA library. S3Pvac synthetically and recombinantly expressed is effective against experimentally and naturally acquired cysticercosis.

Methodology/Principal Findings

In this study, the homologous sequences of two of the S3Pvac peptides, GK1 and KETc1, were identified and further characterized in Taenia crassiceps WFU, Taenia solium, Taenia saginata, Echinococcus granulosus and Echinococcus multilocularis. Comparisons of the nucleotide and amino acid sequences coding for KETc1 and GK1 revealed significant homologies in these species. The predicted secondary structure of GK1 is almost identical between the species, while some differences were observed in the C terminal region of KETc1 according to 3D modeling. A KETc1 variant with a deletion of three C-terminal amino acids protected to the same extent against experimental murine cysticercosis as the entire peptide. On the contrary, immunization with the truncated GK1 failed to induce protection. Immunolocalization studies revealed the non stage-specificity of the two S3Pvac epitopes and their persistence in the larval tegument of all species and in Taenia adult tapeworms.

Conclusions/Significance

These results indicate that GK1 and KETc1 may be considered candidates to be included in the formulation of a multivalent and multistage vaccine against these cestodiases because of their enhancing effects on other available vaccine candidates.  相似文献   
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Researchers have theorized that programs to promote positive citizenship should begin with an opportunity for adolescents to participate in civic activities, such as community service or political volunteering. In this article we extend the theory by arguing that a more systemic approach is needed, in which a civic context is developed to promote citizenship. We hypothesize that living within a consistent civic context leads to civic engagement in late adolescence and into young adulthood. We use a diverse, longitudinal dataset to test this hypothesis. We find that social interactions with peers, parent modeling of civic behaviors, and cultural factors, such as ethnicity-specific practices, cumulatively result in a higher level of civic activities among youth and that a continued context that includes these factors results in a higher level of civic activities into adulthood. The implications of our findings are discussed with regard to program and policy development.  相似文献   
9.
Although climate‐induced shifts in fish distribution have been widely reported at the population level, studies that account for ontogenetic shifts and subregional differences when assessing responses are rare.In this study, groundfish distributional changes in depth, latitude, and longitude were assessed at different size classes by species within nine subregions. We examined large, quality‐controlled datasets of depth‐stratified‐random bottom trawl surveys conducted during summer in three large regions—the Gulf of Alaska and the west coasts of Canada and the United States—over the period 1996–2015, a time period punctuated by a marine “heat wave.” Temporal biases in bottom temperature were minimized by subdividing each region into three subregions, each with short‐duration surveys. Near‐bottom temperatures, weighted by stratum area, were unsynchronized across subregions and exhibited varying subregional interannual variability. The weighted mean bottom depths in the subregions also vary largely among subregions. The centroids (centers of gravity) of groundfish distribution were weighted with catch per unit effort and stratum area for 10 commercially important groundfish species by size class and subregion. Our multivariate analyses showed that there were significant differences in aggregate fish movement responses to warm temperatures across subregions but not among species or sizes. Groundfish demonstrated poleward responses to warming temperatures only in a few subregions and moved shallower or deeper to seek colder waters. The temperature responses of groundfish depended on where they were. Under global warming, groundfish may form geographically distinct thermal ecoregions along the northeast Pacific shelf. Shallow‐depth species exhibited greatly different distributional responses to temperature changes across subregions while deep‐depth species of different subregions tend to have relatively similar temperature responses. Future climate studies would benefit by considering fish distributions on small subregional scales.  相似文献   
10.
Researchers have theorized that programs to promote positive citizenship should begin with an opportunity for adolescents to participate in civic activities, such as community service or political volunteering. In this article we extend the theory by arguing that a more systemic approach is needed, in which a civic context is developed to promote citizenship. We hypothesize that living within a consistent civic context leads to civic engagement in late adolescence and into young adulthood. We use a diverse, longitudinal dataset to test this hypothesis. We find that social interactions with peers, parent modeling of civic behaviors, and cultural factors, such as ethnicity-specific practices, cumulatively result in a higher level of civic activities among youth and that a continued context that includes these factors results in a higher level of civic activities into adulthood. The implications of our findings are discussed with regard to program and policy development.  相似文献   
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