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381.
Astrid Reubsaet Liesbeth A.D.M. van Osch Hein de Vries Maaike R. Op de Coul Lilian Lechner 《Cancer epidemiology》2009,33(3-4):194-200
Background: The present study examined the effects of the campaign “early detection of cancer” on knowledge, attitudes, awareness, and intention to perform passive detection and timely seeking medical help. Further, the campaign was evaluated on recall and recognition and the various campaign components were evaluated. Methods: A longitudinal study using a Solomon four-group design among 784 Dutch adults aged 55 years and older was conducted. Data was gathered by means of telephone interviews. Results: The results showed moderate levels of campaign awareness. After the campaign, solely respondents who received a pre-test questionnaire and were aware of the campaign had significant higher cancer knowledge levels regarding passive detection. Respondents who were only aware of the campaign were significantly more willing to perform passive detection behavior and to timely seek medical help in the future. Further, they were more aware that paying attention to cancer warning signs can lead to early detection of cancer. Conclusions: It can be concluded that solely the combination of the pre-test questionnaire and exposure to the campaign had a significant positive impact on respondents’ cancer knowledge levels. The effects of the campaign on intention and awareness are indistinct and could be a consequence of (the results of) a self-selection bias. It seems that the dose, frequency, and duration of the campaign should be increased in order to substantiate the effects of the campaign. 相似文献
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Arjan P Palstra Denhi Schnabel Maaike C Nieveen Herman P Spaink Guido van den Thillart 《Reproductive biology and endocrinology : RB&E》2010,8(1):27
Background
When European silver eels (Anguilla anguilla) venture into the Atlantic Ocean for their 6,000 km semelparous spawning run to the Sargasso Sea, they are still in a prepubertal stage. Further sexual development appears to be blocked by dopaminergic inhibition of hypothalamus and pituitary activity. Recently, we found that swimming for several weeks in freshwater stimulated the incorporation of fat droplets in the oocytes. So, it was hypothesized that long term swimming in seawater would release the inhibition further and would also stimulate the production of vitellogenin by the liver. 相似文献385.
386.
Hermien van Bokhorst-van de Veen Maaike J. Smelt Michiel Wels Sacha A. F. T. van Hijum Paul de Vos Prof. Michiel Kleerebezem Peter A. Bron 《Biotechnology journal》2013,8(8):895-904
Probiotic bacteria harbor effector molecules that confer health benefits, but also adaptation factors that enable them to persist in the gastrointestinal tract of the consumer. To study these adaptation factors, an antibiotic-resistant derivative of the probiotic model organism Lactobacillus plantarum WCFS1 was repeatedly exposed to the mouse digestive tract by three consecutive rounds of (re)feeding of the longest persisting colonies. This exposure to the murine intestine allowed the isolation of intestine-adapted derivatives of the original strain that displayed prolonged digestive tract residence time. Re-sequencing of the genomes of these adapted derivatives revealed single nucleotide polymorphisms as well as a single nucleotide insertion in comparison with the genome of the original WCFS1 strain. Detailed in silico analysis of the identified genomic modifications pinpointed that alterations in the coding regions of genes encoding cell envelope associated functions and energy metabolism appeared to be beneficial for the gastrointestinal tract survival of L. plantarum WCFS1. This work demonstrates the feasibility of experimental evolution for the enhancement of the gastrointestinal residence time of probiotic strains, while full-genome re-sequencing of the adapted isolates provided clues towards the bacterial functions involved. Enhanced gastrointestinal residence is industrially relevant because it enhances the efficacy of the delivery of viable probiotics in situ. 相似文献
387.
Danita H. Schuurhuis W. Joost Lesterhuis Matthijs Kramer Maaike G. M. Looman Maaike van Hout-Kuijer Gerty Schreibelt A. C. Inge Boullart Erik H. J. G. Aarntzen Daniel Benitez-Ribas Carl G. Figdor Cornelis J. A. Punt I. Jolanda M. de Vries Gosse J. Adema 《Cancer immunology, immunotherapy : CII》2009,58(7):1109-1115
Tumor-derived peptides are used frequently as antigen (Ag) source in dendritic cell (DC) therapy in cancer patients. An alternative
is to load DC with tumor-associated Ag (TAA)-encoding RNA. RNA-loading obviates prior knowledge of CTL and Th epitopes in
the Ag. Multiple epitopes for many HLA alleles (both MHC class I and class II) are encoded by the RNA and loading is independent
of the patient’s HLA make-up. Herein, we determined the optimal conditions for mRNA-electroporation of monocyte-derived DC
for clinical application in relation to different maturation cocktails. The data demonstrate that TAA carcinoembryonic antigen,
gp100 and tyrosinase are expressed already 30 min after electroporation with the encoding mRNA. Moreover, gp100-specific CTL
are activated by gp100 mRNA-electroporated DC. Importantly, we show here that the presence of polyinosinic–polycytidylic acid
[poly(I:C)] in the maturation cocktail prevents effective protein expression of the electroporated mRNA as well as subsequent
CTL recognition. This effect of poly(I:C) correlates with the induction of IFN-induced genes and innate anti-viral effector
molecules in DC. Together these data show that electroporation of mature DC with TAA-encoding mRNA is attractive for use in
DC vaccination protocols in cancer patients, but protein expression should be tested for each maturation cocktail.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Differential effects of jasmonic acid treatment of Brassica nigra on the attraction of pollinators, parasitoids, and butterflies 总被引:1,自引:0,他引:1
Maaike Bruinsma Harm IJdema Joop J.A. van Loon & Marcel Dicke 《Entomologia Experimentalis et Applicata》2008,128(1):109-116
Herbivore-induced plant defences influence the behaviour of herbivores as well as that of their natural enemies. Jasmonic acid is one of the key hormones involved in both these direct and indirect induced defences. Jasmonic acid treatment of plants changes the composition of defence chemicals in the plants, induces volatile emission, and increases the production of extrafloral nectar. However, few studies have addressed the potential influence of induced defences on flower nectar chemistry and pollinator behaviour. These have shown that herbivore damage can affect pollination rates and plant fitness. Here, we have investigated the effect of jasmonic acid treatment on floral nectar production and the attraction of pollinators, as well as the effect on the behaviour of an herbivore and its natural enemy. The study system consisted of black mustard plants, Brassica nigra L. (Brassicaceae), pollinators of Brassica nigra (i.e., honeybees and syrphid flies), a specialist herbivore, Pieris rapae L. (Lepidoptera: Pieridae), and a parasitoid wasp that uses Pieris larvae as hosts, Cotesia glomerata L. (Hymenoptera: Braconidae). We show that different trophic levels are differentially affected by jasmonic acid-induced changes. While the herbivore prefers control leaves over jasmonic acid-treated leaves for oviposition, the parasitoid C. glomerata is more attracted to jasmonic acid-treated plants than to control plants. We did not observe differences in pollinator preference, the rates of flower visitation by honeybees and syrphid flies were similar for control and jasmonic acid-treated plants. Plants treated with jasmonic acid secreted less nectar than control plants and the concentrations of glucose and fructose tended to be lower than in nectar from control plants. Jasmonic acid treatment resulted in a lower nectar production than actual feeding damage by P. rapae caterpillars. 相似文献