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1.
Robin J. Lake Brecht Devleesschauwer George Nasinyama Arie H. Havelaar Tanja Kuchenmüller Juanita A. Haagsma Helen H. Jensen Nasreen Jessani Charline Maertens de Noordhout Frederick J. Angulo John E. Ehiri Lindita Molla Friday Agaba Suchunya Aungkulanon Yuko Kumagai Niko Speybroeck 《PloS one》2015,10(12)
2.
Brecht Devleesschauwer Juanita A. Haagsma Frederick J. Angulo David C. Bellinger Dana Cole D?rte D?pfer Aamir Fazil Eric M. Fèvre Herman J. Gibb Tine Hald Martyn D. Kirk Robin J. Lake Charline Maertens de Noordhout Colin D. Mathers Scott A. McDonald Sara M. Pires Niko Speybroeck M. Kate Thomas Paul R. Torgerson Felicia Wu Arie H. Havelaar Nicolas Praet 《PloS one》2015,10(12)
Background
The Foodborne Disease Burden Epidemiology Reference Group (FERG) was established in 2007 by the World Health Organization to estimate the global burden of foodborne diseases (FBDs). This paper describes the methodological framework developed by FERG''s Computational Task Force to transform epidemiological information into FBD burden estimates.Methods and Findings
The global and regional burden of 31 FBDs was quantified, along with limited estimates for 5 other FBDs, using Disability-Adjusted Life Years in a hazard- and incidence-based approach. To accomplish this task, the following workflow was defined: outline of disease models and collection of epidemiological data; design and completion of a database template; development of an imputation model; identification of disability weights; probabilistic burden assessment; and estimating the proportion of the disease burden by each hazard that is attributable to exposure by food (i.e., source attribution). All computations were performed in R and the different functions were compiled in the R package ''FERG''. Traceability and transparency were ensured by sharing results and methods in an interactive way with all FERG members throughout the process.Conclusions
We developed a comprehensive framework for estimating the global burden of FBDs, in which methodological simplicity and transparency were key elements. All the tools developed have been made available and can be translated into a user-friendly national toolkit for studying and monitoring food safety at the local level. 相似文献3.
Protease-catalysed coupling of N-protected amino acids and peptides with 4-aminoantipyrine 总被引:1,自引:0,他引:1
The enzymatic synthesis of N-protected l-aminoacyl- and l-peptidyl-antipyrine amides was accomplished by proteases from different classes. Serine and cysteine proteases proved to
be suitable tools for the production of amino acids and peptides conjugated to 4-aminoantipyrine, whereas metalloproteases
do not seem to be very qualified for accepting this nucleophile. The product yields were optimised by applying ample opportunities
of medium engineering, e.g. aqueous-organic, biphasic, suspension and solid-to-solid reaction systems. Thus, yields up to
100% could be obtained. The products were purified and characterised by polarimetry and NMR spectroscopy. These results broaden
the common knowledge of the catalytic potential of proteases, in particular with regard to the suitability of a special heterocyclic
1,2-amino ketone as a nucleophile for the biocatalytic amidation of amino acids and peptides. 相似文献
4.
Hatching asynchrony in avian species generally leads to a size hierarchy among siblings, favouring the first-hatched chicks. Maternally deposited hormones affect the embryo and chick's physiology and behaviour. It has been observed that progesterone, a hormone present at higher levels than other steroid hormones in egg yolks, is negatively related to body mass in embryos, chicks and adults. A differential within-clutch progesterone deposition could therefore be linked to the size hierarchy between siblings and to the resulting brood reduction. We tested whether yolk progesterone levels differed between eggs according to future parental ability to feed the entire clutch in wild rockhopper penguins Eudyptes chrysocome. This species presents a unique reversed egg-size dimorphism and hatching asynchrony, with the larger second-laid egg (B-egg) hatching before the smaller first-laid egg (A-egg). Yolk progesterone levels increased only slightly with female body mass at laying. However, intra-clutch ratios were not related to female body mass. On the other hand, yolk progesterone levels increased significantly with the date of laying onset for A-eggs while they decreased for B-eggs. Early clutches therefore had proportionally more progesterone in the B-egg compared to the A-egg while late clutches had proportionally less progesterone in the B-egg. We propose that females could strategically regulate yolk progesterone deposition within clutches according to the expected food availability during chick growth, an adaptive strategy to adjust brood reduction to conditions. We also discuss these results, relating to yolk progesterone, in the broader context of other yolk steroids. 相似文献
5.
Examination of the Kinetics of Herpes Simplex Virus Glycoprotein D Binding to the Herpesvirus Entry Mediator, Using Surface Plasmon Resonance 总被引:4,自引:8,他引:4 下载免费PDF全文
Sharon H. Willis Ann H. Rux Charline Peng J. Charles Whitbeck Anthony V. Nicola Huan Lou Wangfang Hou Lisa Salvador Roselyn J. Eisenberg Gary H. Cohen 《Journal of virology》1998,72(7):5937-5947
Previously, we showed that truncated soluble forms of herpes simplex virus (HSV) glycoprotein D (gDt) bound directly to a truncated soluble form of the herpesvirus entry mediator (HveAt, formerly HVEMt), a cellular receptor for HSV. The purpose of the present study was to determine the affinity of gDt for HveAt by surface plasmon resonance and to compare and contrast the kinetics of an expanded panel of gDt variants in binding to HveAt in an effort to better understand the mechanism of receptor binding and virus entry. Both HveAt and gDt are dimers in solution and interact with a 2:1 stoichiometry. With HveAt, gD1(306t) (from the KOS strain of HSV-1) had a dissociation constant (KD) of 3.2 × 10−6 M and gD2(306t) had a KD of 1.5 × 10−6 M. The interaction between gDt and HveAt fits a 1:1 Langmuir binding model, i.e., two dimers of HveAt may act as one binding unit to interact with one dimer of gDt as the second binding unit. A gD variant lacking all signals for N-linked oligosaccharides had an affinity for HveAt similar to that of gD1(306t). A variant lacking the bond from cysteine 1 to cysteine 5 had an affinity for HveAt that did not differ from that of the wild type. However, variants with double cysteine mutations that eliminated either of the other two disulfide bonds showed decreased affinity for HveAt. This result suggests that two of the three disulfide bonds of gD are important for receptor binding. Four nonfunctional gDt variants, each representing one functional domain of gD, were also studied. Mutations in functional regions I and II drastically decreased the affinity of gDt for HveAt. Surprisingly, a variant with an insertion in functional region III had a wild-type level of affinity for HveAt, suggesting that this domain may function in virus entry at a step other than receptor binding. A variant with a deletion in functional region IV [gD1(Δ290-299t)] exhibited a 100-fold enhancement in affinity for HveAt (KD = 3.3 × 10−8 M) due mainly to a 40-fold increase in its kinetic on rate. This agrees with the results of other studies showing the enhanced ability of gD1(Δ290-299t) to block infection. Interestingly, all the variants with decreased affinities for HveAt exhibited decreased kinetic on rates but only minor changes in their kinetic off rates. The results suggest that once the complex between gDt and HveAt forms, its stability is unaffected by a variety of changes in gD. 相似文献
6.
Erica Lana Mahbod Khanbolouki Charline Degavre Eva-Britt Samuelsson Elisabet Åkesson Bengt Winblad Evren Alici Christina Unger Lithner Homira Behbahani 《Molecular neurobiology》2017,54(2):874-887
Studies on the mechanisms of neuronal amyloid-β (Aβ) internalisation are crucial for understanding the neuropathological progression of Alzheimer’s disease (AD). We here investigated how extracellular Aβ peptides are internalised and focused on three different pathways: (i) via endocytic mechanisms, (ii) via the receptor for advanced glycation end products (RAGE) and (iii) via the pore-forming protein perforin. Both Aβ40 and Aβ42 were internalised in retinoic acid differentiated neuroblastoma (RA-SH-SY5Y) cells. A higher concentration was required for Aβ40 (250 nM) compared with Aβ42 (100 nM). The internalised Aβ40 showed a dot-like pattern of distribution whereas Aβ42 accumulated in larger and distinct formations. By confocal microscopy, we showed that Aβ40 and Aβ42 co-localised with mitochondria, endoplasmic reticulum (ER) and lysosomes. Aβ treatment of human primary cortical neurons (hPCN) confirmed our findings in RA-SH-SY5Y cells, but hPCN were less sensitive to Aβ; therefore, a 20 (Aβ40) and 50 (Aβ42) times higher concentration was needed for inducing uptake. The blocking of endocytosis completely inhibited the internalisation of Aβ peptides in RA-SH-SY5Y cells and hPCN, indicating that this is a major pathway by which Aβ enters the cells. In addition, the internalisation of Aβ42, but not Aβ40, was reduced by 55 % by blocking RAGE. Finally, for the first time we showed that pore formation in cell membranes by perforin led to Aβ internalisation in hPCN. Understanding how Aβ is internalised sheds light on the pathological role of Aβ and provides further ideas of inhibitory strategies for preventing Aβ internalisation and the spreading of neurodegeneration in AD. 相似文献
7.
F. Stephen Dobson Charline Couchoux Pierre Jouventin 《Ethology : formerly Zeitschrift fur Tierpsychologie》2011,117(10):872-879
Species in which the sexes equally exhibit colourful ornaments are an issue for evolutionary theory. Among several hypotheses, sexual selection for mutual mate choice and social selection for signals of behavioural dominance are most commonly supported. We examined the previously documented sex‐similar size of yellow‐orange ear patches in the king penguin, Aptenodytes patagonicus. This species is monogamous and pairs just before reproduction. Raising a chick requires considerable effort by both parents, as they alternate care of their single offspring with foraging at sea. The size of the ear patches appears to signal aggressive territoriality in the breeding colony for both sexes. However, experiments suggest that females prefer large patch size during mate choice, and males do not prefer this trait. We tested whether the size of the coloured ear patch was influenced by sexual selection for couples that had recently paired. We used analyses of covariance to compare the size of the ear patch to a measure of body size and then tested for the difference between males and females. Males were 6.2% larger in ear patch width and 7.7% larger in ear patch area than females, and the distance between the ear patches over the head was 7.5% smaller in males, with all differences highly significant. Consequently, sexual selection appears to favour larger ear patches in males, possibly because of an excess of males that promotes female choice. Social selection also appears to favour the evolutionary maintenance of ear patches of males, and thus both types of selection may contribute to enlarged ear patches. 相似文献
8.
Negar Seyed Tahereh Taheri Charline Vauchy Magalie Dosset Yann Godet Ali Eslamifar Iraj Sharifi Olivier Adotevi Christophe Borg Pierre Simon Rohrlich Sima Rafati 《PloS one》2014,9(10)
Background
There are several reports demonstrating the role of CD8 T cells against Leishmania species. Therefore peptide vaccine might represent an effective approach to control the infection. We developed a rational polytope-DNA construct encoding immunogenic HLA-A2 restricted peptides and validated the processing and presentation of encoded epitopes in a preclinical mouse model humanized for the MHC-class-I and II.Methods and Findings
HLA-A*0201 restricted epitopes from LPG-3, LmSTI-1, CPB and CPC along with H-2Kd restricted peptides, were lined-up together as a polytope string in a DNA construct. Polytope string was rationally designed by harnessing advantages of ubiquitin, spacers and HLA-DR restricted Th1 epitope. Endotoxin free pcDNA plasmid expressing the polytope was inoculated into humanized HLA-DRB1*0101/HLA-A*0201 transgenic mice intramuscularly 4 days after Cardiotoxin priming followed by 2 boosters at one week interval. Mice were sacrificed 10 days after the last booster, and splenocytes were subjected to ex-vivo and in-vitro evaluation of specific IFN-γ production and in-vitro cytotoxicity against individual peptides by ELISpot and standard chromium-51(51Cr) release assay respectively. 4 H-2Kd and 5 HLA-A*0201 restricted peptides were able to induce specific CD8 T cell responses in BALB/C and HLA-A2/DR1 mice respectively. IFN-γ and cytolytic activity together discriminated LPG-3-P1 as dominant, LmSTI-1-P3 and LmSTI-1-P6 as subdominant with both cytolytic activity and IFN-γ production, LmSTI-1-P4 and LPG-3-P5 as subdominant with only IFN-γ production potential.Conclusions
Here we described a new DNA-polytope construct for Leishmania vaccination encompassing immunogenic HLA-A2 restricted peptides. Immunogenicity evaluation in HLA-transgenic model confirmed CD8 T cell induction with expected affinities and avidities showing almost efficient processing and presentation of the peptides in relevant preclinical model. Further evaluation will determine the efficacy of this polytope construct protecting against infectious challenge of Leishmania. Fortunately HLA transgenic mice are promising preclinical models helping to speed up immunogenicity analysis in a human related mouse model. 相似文献9.
10.
George Streisinger Fred Singer Charline Walker Donna Knauber Nancy Dower 《Genetics》1986,112(2):311-319
The gol-1, gol-2, alb-1 and spa-1 mutations affect pigment pattern in the zebrafish. We show here that these loci are unlinked to each other. In addition, gene-centromere distances were determined for these loci by analysis of half-tetrads obtained by the inhibition of the second meiotic division. The fractions of tetratype (second-division segregation) tetrads range from 0.24 (spa-1) to 0.89 (gol-1). The observation of greater than 0.67 second-division segregation indicates that the zebrafish has high chiasma interference. 相似文献