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41.
Variation in parental rearing expenditure triggers short‐term physiological effects on offspring in a long‐lived seabird 下载免费PDF全文
Erick González‐Medina José Alfredo Castillo‐Guerrero Francisco Santiago‐Quesada Auxiliadora Villegas José A. Masero Juan M. Sánchez‐Guzmán Guillermo Fernández 《Ibis》2016,158(2):305-314
Parental care in long‐lived bird species involves a trade‐off between the benefits of increasing the effort expended on current offspring and the costs that this represents for future reproductive output. Under regimes of high environmental variability, long‐lived seabirds can adjust their breeding effort to buffer the negative effects of this variability on their offspring. However, the potential impacts of variation in breeding effort on offspring physiology in the short term and on longer‐term survival are poorly understood. In this study, we manipulated brood age through a cross‐fostering experiment to assess whether increasing or decreasing parental reproductive expenditure led to costs in Blue‐footed Booby Sula nebouxii chicks. Specifically, we tested the consequences of altered parental reproductive expenditure on the offspring's physiological condition (plasma metabolites, heterophil to lymphocyte ratio (H/L) and body condition index (BCI)) and survival. Offspring from broods in which parental investment was experimentally increased showed a lower BCI and lower alkaline phosphatase levels and higher H/L ratios than controls. Conversely, offspring showed the opposite pattern when reproductive expenditure was experimentally decreased. We observed no effects of manipulation of parental investment on triglyceride levels or on survival rates. Although our findings suggest that Blue‐footed Booby parents have the ability to adjust their breeding effort according to the demands of their offspring, parental effort could influence the effect of hatching order by suppressing the aggressive tendency of the senior chick. 相似文献
42.
J. Jaime Miranda Victor M. Herrera Julio A. Chirinos Luis F. Gómez Pablo Perel Rafael Pichardo Angel González José R. Sánchez Catterina Ferreccio Ximena Aguilera Eglé Silva Myriam Oróstegui Josefina Medina-Lezama Cynthia M. Pérez Erick Suárez Ana P. Ortiz Luis Rosero Noberto Schapochnik Zulma Ortiz Daniel Ferrante Juan P. Casas Leonelo E. Bautista 《PloS one》2013,8(1)
Background
Limited knowledge on the prevalence and distribution of risk factors impairs the planning and implementation of cardiovascular prevention programs in the Latin American and Caribbean (LAC) region.Methods and Findings
Prevalence of hypertension, diabetes mellitus, abnormal lipoprotein levels, obesity, and smoking were estimated from individual-level patient data pooled from population-based surveys (1998–2007, n = 31,009) from eight LAC countries and from a national survey of the United States (US) population (1999–2004) Age and gender specific prevalence were estimated and age-gender adjusted comparisons between both populations were conducted. Prevalence of diabetes mellitus, hypertension, and low high-density lipoprotein (HDL)-cholesterol in LAC were 5% (95% confidence interval [95% CI]: 3.4, 7.9), 20.2% (95% CI: 12.5, 31), and 53.3% (95% CI: 47, 63.4), respectively. Compared to LAC region’s average, the prevalence of each risk factor tended to be lower in Peru and higher in Chile. LAC women had higher prevalence of obesity and low HDL-cholesterol than men. Obesity, hypercholesterolemia, and hypertriglyceridemia were more prevalent in the US population than in LAC population (31 vs. 16.1%, 16.8 vs. 8.9%, and 36.2 vs. 26.5%, respectively). However, the prevalence of low HDL-cholesterol was higher in LAC than in the US (53.3 vs. 33.7%).Conclusions
Major cardiovascular risk factors are highly prevalent in LAC region, in particular low HDL-cholesterol. In addition, marked differences do exist in this prevalence profile between LAC and the US. The observed patterns of obesity-related risk factors and their current and future impact on the burden of cardiovascular diseases remain to be explained. 相似文献43.
Caroline Martin Erick Provost† Maurice Roux‡ Claude Bruchou§ Didier Crauser Jean-Luc Clement† Yves Le Conte 《Physiological Entomology》2001,26(4):362-370
Abstract. One way in which Apis mellifera honey bees resist Varroa destructor is by detection and elimination of nestmates. This study uses behavioural tests and electroanntennography to assess the role of chemostimuli in recognition by honey bees of this acarian ectoparasite. Behavioural tests using living or dead parasites involved observation of honey bee grooming activity (antennation) under controlled conditions in Petri dishes, and removal behaviour (uncapping and elimination of parasitized and unparasitized control brood cells) under natural conditions. Some bees from colonies with both small and large parasite populations showed aggressive behaviour (biting). No difference was observed according to whether the mite was dead or alive. Under natural conditions, bees uncapped more parasitized cells than control cells. Electroantennographic tests were performed to measure sensitivity to various Varroa extracts at three concentrations (10, 20 and 30 Varroa Equivalents). Only 30 Varroa Equivalent methanol extracts made from Varroa collected from brood cells elicited significantly greater antennal response than controls (pure solvent). All three methanol extracts elicited significantly greater antennal response than controls. No response was observed using Varroa extracts made with acetone or hexane. These findings suggest that polar products may act as chemostimuli for recognition of V. destructor by honey bees. Further study will be necessary to determine which polar products are involved in this recognition and assess grooming and removal behaviour using these products. 相似文献
44.
Microbial metabolomics: past,present and future methodologies 总被引:1,自引:0,他引:1
Mashego MR Rumbold K De Mey M Vandamme E Soetaert W Heijnen JJ 《Biotechnology letters》2007,29(1):1-16
Microbial metabolomics has received much attention in recent years mainly because it supports and complements a wide range
of microbial research areas from new drug discovery efforts to metabolic engineering. Broadly, the term metabolomics refers
to the comprehensive (qualitative and quantitative) analysis of the complete set of all low molecular weight metabolites present
in and around growing cells at a given time during their growth or production cycle. This review focuses on the past, current
and future development of various experimental protocols in the rapid developing area of metabolomics in the ongoing quest
to reliably quantify microbial metabolites formed under defined physiological conditions. These developments range from rapid
sample collection, instant quenching of microbial metabolic activity, extraction of the relevant intracellular metabolites
as well as quantification of these metabolites using enzyme based and or modern high tech hyphenated analytical protocols,
mainly chromatographic techniques coupled to mass spectrometry (LC-MSn, GC-MSn, CE-MSn), where n indicates the number of tandem mass spectrometry, and nuclear magnetic resonance spectroscopy (NMR). 相似文献
45.
Van Bogaert IN Saerens K De Muynck C Develter D Soetaert W Vandamme EJ 《Applied microbiology and biotechnology》2007,76(1):23-34
Sophorolipids are surface-active compounds synthesized by a selected number of yeast species. They have been known for over
40 years, but because of growing environmental awareness, they recently regained attention as biosurfactants due to their
biodegradability, low ecotoxicity, and production based on renewable resources. In this paper, an overview is given of the
producing yeast strains and various aspects of fermentative sophorolipid production. Also, the biochemical pathways and regulatory
mechanisms involved in sophorolipid biosynthesis are outlined. To conclude, a summary is given on possible applications of
sophorolipids, either as native or modified molecules. 相似文献
46.
DNA repair is known as a defense mechanism against genotoxic insults. However, the most lethal type of DNA damages, double-strand DNA breaks (DSBs), can be produced by DNA repair. We have previously demonstrated that when long patch base excision repair attempts to repair a synthetic substrate containing two uracils, the repair produces DSBs (Vispe, S. and Satoh, M. S. (2000) J. Biol. Chem. 275, 27386-27392 and Vispe, S., Ho, E. L., Yung, T. M., and Satoh, M. S. (2003) J. Biol. Chem. 278, 35279-35285). In this synthetic substrate, the two uracils are located on the opposite DNA strands (separated by an intervening sequence stable at 37 degrees C) and represent a high risk site for DSB formation. It is not clear, however, whether similar high risk sites are also induced in genomic DNA by exposure to DNA damaging agents. Thus, to investigate the mechanisms of DSB formation, we have modified the DSB formation assay developed previously and demonstrated that high risk sites for DSB formation are indeed generated in genomic DNA by exposure of cells to alkylating agents. In fact, genomic DNA containing alkylated base damages, which could represent high risk sites, are converted into DSBs by enzymes present in extracts prepared from cells derived from clinically normal individuals. Furthermore, DSBs are also produced by extracts from cells derived from ataxia-telangiectasia patients who show cancer proneness due to an impaired response to DSBs. These results suggest the presence of a novel link between base damage formation and DSBs and between long patch base excision repair and human diseases that occur due to an impaired response to DSB. 相似文献
47.
Diard M Baeriswyl S Clermont O Gouriou S Picard B Taddei F Denamur E Matic I 《Microbes and infection / Institut Pasteur》2007,9(2):214-223
Extraintestinal pathogenic Escherichia coli (ExPEC) strains cause disease by invading normally sterile niches within the host body, e.g., urinary tract, blood and cerebrospinal fluid. Infections due to ExPEC strains, in particular urinary tract infections, cause considerable morbidity and significant health-care costs. The goal of our study is to evaluate whether Caenorhabditis elegans can be used as a model to study phenotypic and genetic virulence determinants of ExPEC strains. For this purpose, we used a collection of 31 E. coli strains isolated during acute extra-intestinal infections or from the feces of healthy individuals. For all strains, the phylogeny, the presence of ExPEC virulence factors, the resistance to biologically relevant stressors (bile, human serum and lysozyme), the motility, the growth rate, the virulence in C. elegans and in a murine septicaemia model has been established. The results show that there is a strong link between virulence in C. elegans and certain phenotypic and genetic virulence predictors of ExPEC strains determinable in vitro. Furthermore, there is a significant correlation between virulence of different ExPEC strains in C. elegans and in the murine model. Therefore, our results suggest that C. elegans can be used as a model to study virulence determinants of ExPEC strains. 相似文献
48.
Molecular Evidence for the Polyphyly of Macrotrichomonas (Parabasalia: Cristamonadea) and a Proposal for Macrotrichomonoides n. gen. 下载免费PDF全文
Gillian H. Gile Erick R. James Noriko Okamoto Kevin J. Carpenter Rudolf H. Scheffrahn Patrick J. Keeling 《The Journal of eukaryotic microbiology》2015,62(4):494-504
Macrotrichomonas (Cristamonadea: Parabasalia) is an anaerobic, amitochondriate flagellate symbiont of termite hindguts. It is noteworthy for being large but not structurally complex compared with other large parabasalians, and for retaining a structure similar in appearance to the undulating membrane (UM) of small flagellates closely related to cristamonads, e.g. Tritrichomonas. Here, we have characterised the SSU rDNA from two species described as Macrotrichomonas: M. restis Kirby 1942 from Neotermes jouteli and M. lighti Connell 1932 from Paraneotermes simplicicornis. These species do not form a clade: M. lighti branches with previously characterised Macrotrichomonas sequences from Glyptotermes, while M. restis branches with the genus Metadevescovina. We examined the M. restis UM by light microscopy, scanning electron microscopy, and transmission electron microscopy, and we find common characteristics with the proximal portion of the robust recurrent flagellum of devescovinids. Altogether, we show the genus Macrotrichomonas to be polyphyletic and propose transferring M. restis to a new genus, Macrotrichomonoides. We also hypothesise that the macrotrichomonad body plan represents the ancestral state of cristamonads, from which other major forms evolved. 相似文献
49.
Strains phenotypically indistinguishable from Escherichia coli and belonging to at least five distinct cryptic lineages, named Escherichia clades I to V, that are genetically divergent from E. coli yet members of the genus have been recently found using multi-locus sequence typing (MLST). Very few epidemiological data are available on these strains as their detection by MLST is not suitable for large-scale studies. In this work, we developed a rapid PCR method based on aes and chuA allele-specific amplifications that assigns a strain a cryptic lineage membership. By screening more than 3500 strains with this approach, we show that the cryptic lineages of Escherichia are unlikely to be detected in human faecal samples (2-3% frequency) and even less likely to be isolated from extra-intestinal body sites (< 1% frequency). They are more abundant in animal faeces ranging from 3-8% in non-human mammals to 8-28% in birds. Overall, the strains from the clade V are the most abundant and from the clade II very rare. These results suggest that members of the cryptic clades are unlikely to be of significance to human and health but may influence the use of 'E. coli' as an indicator of water quality. 相似文献
50.
Erick D. Smith Matthew D. Whiting David R. Rudell 《Metabolomics : Official journal of the Metabolomic Society》2011,7(1):126-133
Increasing costs and decreasing labor availability for sweet cherry harvest in Washington State, USA, has reinvigorated commercial
and research interest of mechanized harvest. Ethephon (2-chloroethyl phosphonic acid) can be used to improve fruit abscission
for mechanical harvest. Our previous work shows that 3.5 l ha−1 ethephon enhances red color and reduces firmness of the cultivar ‘Bing’. In the current study, we used metabolic profiling
of cultivars ‘Bing’, Chelan’, and ‘Skeena’ fruit meso and exocarp tissue to better understand underlying quality-related metabolism
associated with ethephon application. Trees were treated using air-blast sprayer 13–14 days prior to harvest and fruit samples
were harvested every 7–10 days starting at least 17 days prior to commercial harvest. Nearly 200 identified and partially
characterized metabolites from mesocarp and exocarp tissue were characterized and evaluated. Principal component analysis
models revealed changes in the metabolome associated with both natural ripening and ethephon-induced changes, including associations
to key color, acid, and sugar components, such as cyanidin 3-glucoside, malic acid and sugar metabolism. 相似文献