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71.
Production of ex vivo lipopolysaccharide-induced tumor necrosis factor-α, interleukin-1β, and interleukin-6 is suppressed by trans-resveratrol in a concentration-dependent manner 下载免费PDF全文
Jean-Francois Marier Keguan Chen Peter Prince George Scott Jerome R.E. del Castillo Pascal Vachon 《Canadian journal of veterinary research》2005,69(2):151-154
Trans-resveratrol is a biologically active compound present in certain foods that has anti-inflammatory and anticancer properties. These beneficial effects are derived from both the immune system and cytokines. The purpose of this study was to determine the immunomodulatory effect of trans-resveratrol on the ex vivo production of inflammatory and anti-inflammatory cytokines stimulated by lipopolysaccharides (LPS). Trans-resveratrol (0, 0.01, 0.1, 1, and 10 microM) was added to blood samples from male Sprague-Dawley rats (n = 6) along with 100 U of LPS (Escherichia coli serotype, 055B5). The samples were then incubated for 4 h at 37 degrees C and centrifuged. Finally, concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 in the plasma were analyzed using an enzyme-linked immunosorbent assay (ELISA). The production of inflammatory (TNF-alpha and IL-1beta) and anti-inflammatory (IL-6) cytokines was suppressed by trans-resveratrol in a concentration-dependent manner. These results support the hypothesis that the immunomodulatory effect of trans-resveratrol plays an important role in disease conditions that involve an overproduction of inflammatory cytokines. 相似文献
72.
Ducrot C Bed'hom B Béringue V Coulon JB Fourichon C Guérin JL Krebs S Rainard P Schwartz-Cornil I Torny D Vayssier-Taussat M Zientara S Zundel E Pineau T 《Veterinary research》2011,42(1):96
ABSTRACT: In the rapidly changing context of research on animal health, INRA launched a collective discussion on the challenges facing the field, its distinguishing features, and synergies with biomedical research. As has been declared forcibly by the heads of WHO, FAO and OIE, the challenges facing animal health, beyond diseases transmissible to humans, are critically important and involve food security, agriculture economics, and the ensemble of economic activities associated with agriculture. There are in addition issues related to public health (zoonoses, xenobiotics, antimicrobial resistance), the environment, and animal welfare.Animal health research is distinguished by particular methodologies and scientific questions that stem from the specific biological features of domestic species and from animal husbandry practices. It generally does not explore the same scientific questions as research on human biology, even when the same pathogens are being studied, and the discipline is rooted in a very specific agricultural and economic context.Generic and methodological synergies nevertheless exist with biomedical research, particularly with regard to tools and biological models. Certain domestic species furthermore present more functional similarities with humans than laboratory rodents.The singularity of animal health research in relation to biomedical research should be taken into account in the organization, evaluation, and funding of the field through a policy that clearly recognizes the specific issues at stake. At the same time, the One Health approach should facilitate closer collaboration between biomedical and animal health research at the level of research teams and programmes. 相似文献
73.
Avian pathogenic Escherichia coli (APEC) are often found in poultry and are responsible for a set of diseases, commonly referred to as avian colibacillosis. One of the important virulence factors is adhesion to different epithelial surfaces, which is mediated by pili. P pili are thought to play a role by means of their PapG adhesin, which occurs in three molecular variants: PapGI, PapGII and PapGIII. This study is the first to determine and analyse the distribution of the different papG alleles in APEC. Our results show a significant predominance of the papGII allele above all other alleles or allele combinations. No statistically significant associations could be found between papG allele distribution and the type of bird, organ of isolation and O serogroup. Finally, the papGII and papGIII sequences showed high homology with mammalian (including human) source papG sequences. 相似文献
74.
Vermot J Gallego Llamas J Fraulob V Niederreither K Chambon P Dollé P 《Science (New York, N.Y.)》2005,308(5721):563-566
A striking characteristic of vertebrate embryos is their bilaterally symmetric body plan, which is particularly obvious at the level of the somites and their derivatives such as the vertebral column. Segmentation of the presomitic mesoderm must therefore be tightly coordinated along the left and right embryonic sides. We show that mutant mice defective for retinoic acid synthesis exhibit delayed somite formation on the right side. Asymmetric somite formation correlates with a left-right desynchronization of the segmentation clock oscillations. These data implicate retinoic acid as an endogenous signal that maintains the bilateral synchrony of mesoderm segmentation, and therefore controls bilateral symmetry, in vertebrate embryos. 相似文献
75.
Dominique Robert Jun Shoji Pascal Sirois Akinori Takasuka Ignacio A. Catalán Arild Folkvord Stuart A. Ludsin Myron A. Peck Su Sponaugle Patricia M. Ayón Richard D. Brodeur Emily Y. Campbell Evan K. D'Alessandro John F. Dower Louis Fortier Alberto G. García Klaus B. Huebert Marc Hufnagl Shin-ichi Ito Mikimasa Joh Francis Juanes Mitsuo Nyuji Yoshioki Oozeki Guido Plaza Motomitsu Takahashi Yosuke Tanaka Naoki Tojo Shingo Watari Naotaka Yasue Pierre Pepin 《Fish and Fisheries》2023,24(5):863-888
Early life survival is critical to successful replenishment of fish populations, and hypotheses developed under the Growth-Survival Paradigm (GSP) have guided investigations of controlling processes. The GSP postulates that recruitment depends on growth and mortality rates during early life stages, as well as their duration, after which the mortality declines substantially. The GSP predicts a shift in the frequency distribution of growth histories with age towards faster growth rates relative to the initial population because slow-growing individuals are subject to high mortality (via starvation and predation). However, mortality data compiled from 387 cases published in 153 studies (1971–2022) showed that the GSP was only supported in 56% of cases. Selection against slow growth occurred in two-thirds of field studies, leaving a non-negligible fraction of cases showing either an absence of or inverse growth-selective survival, suggesting the growth-survival relationship is more complex than currently considered within the GSP framework. Stochastic simulations allowed us to assess the influence of key intrinsic and extrinsic factors on the characteristics of surviving larvae and identify knowledge gaps on the drivers of variability in growth-selective survival. We suggest caution when interpreting patterns of growth selection because changes in variance and autocorrelation of individual growth rates among cohorts can invalidate fundamental GSP assumptions. We argue that breakthroughs in recruitment research require a comprehensive, population-specific characterization of the role of predation and intrinsic factors in driving variability in the distribution and autocorrelation of larval growth rates, and of the life stage corresponding to the endpoint of pre-recruited life. 相似文献
76.
Alvin A. Gajadhar Edoardo Pozio H. Ray Gamble Karsten Nöckler Charlotte Maddox-Hyttel Lorry B. Forbes Isabelle Vallée Patrizia Rossi Albert Marinculić Pascal Boireau 《Veterinary parasitology》2009,159(3-4):197-205
Because of its role in human disease, there are increasing global requirements for reliable diagnostic and control methods for Trichinella in food animals to ensure meat safety and to facilitate trade. Consequently, there is a need for standardization of methods, programs, and best practices used in the control of Trichinella and trichinellosis. This review article describes the biology and epidemiology of Trichinella, and describes recommended test methods as well as modified and optimized procedures that are used in meat inspection programs. The use of ELISA for monitoring animals for infection in various porcine and equine pre- and post-slaughter programs, including farm or herd certification programs is also discussed. A brief review of the effectiveness of meat processing methods, such as freezing, cooking and preserving is provided. The importance of proper quality assurance and its application in all aspects of a Trichinella diagnostic system is emphasized. It includes the use of international quality standards, test validation and standardization, critical control points, laboratory accreditation, certification of analysts and proficiency testing. Also described, are the roles and locations of international and regional reference laboratories for trichinellosis where expert advice and support on research and diagnostics are available. 相似文献
77.
Stavros?ChatzifotisEmail author Ioannis?E.?Papadakis Pascal?Divanach 《Fisheries Science》2005,71(6):1243-1248
ABSTRACT: This study is concerned with the effect of hyrdated diets on growth and feed performance of Dentex dentex . Three levels of dietary water were tested: 7%, 20% and 40%. For the 7% level a commercial feed was used and the 20% and 40% water levels were obtained after adding an appropriate amount of deionized water to the commercial feed and mixing the pellets well. The diets were offered to fish by self-feeders, by which fish were allowed continuous access to diets after activating the self-feeders; by belt feeders, by which the diets were fed continuously and in excess over a 12 h interval; and by hand to apparent satiation two times a day. After 151 days of feeding, the group fed on the 20%-water diet showed significantly ( P < 0.05) higher growth rate than the 7 and 40% groups, while no significant differences were observed in feed conversion rate or daily feed consumption. The means of feed delivery did not influence growth rate. Self-feeder, belt and hand feeding all gave comparable growth. Fish fed the more condensed 7%-water diet had smaller stomachs than fish fed the larger volume 40%-water diet. In the stomach, all groups of fish hydrated their digesta within 2 h after feeding to a moisture content of around 60%. Apparently no difference in digestive process was observed between groups. It was concluded that the addition of water in diet at the level of 20% has a beneficial effect on dentex growth. 相似文献
78.
von Bernuth H Picard C Jin Z Pankla R Xiao H Ku CL Chrabieh M Mustapha IB Ghandil P Camcioglu Y Vasconcelos J Sirvent N Guedes M Vitor AB Herrero-Mata MJ Aróstegui JI Rodrigo C Alsina L Ruiz-Ortiz E Juan M Fortuny C Yagüe J Antón J Pascal M Chang HH Janniere L Rose Y Garty BZ Chapel H Issekutz A Maródi L Rodriguez-Gallego C Banchereau J Abel L Li X Chaussabel D Puel A Casanova JL 《Science (New York, N.Y.)》2008,321(5889):691-696
MyD88 is a key downstream adapter for most Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). MyD88 deficiency in mice leads to susceptibility to a broad range of pathogens in experimental settings of infection. We describe a distinct situation in a natural setting of human infection. Nine children with autosomal recessive MyD88 deficiency suffered from life-threatening, often recurrent pyogenic bacterial infections, including invasive pneumococcal disease. However, these patients were otherwise healthy, with normal resistance to other microbes. Their clinical status improved with age, but not due to any cellular leakiness in MyD88 deficiency. The MyD88-dependent TLRs and IL-1Rs are therefore essential for protective immunity to a small number of pyogenic bacteria, but redundant for host defense to most natural infections. 相似文献
79.
Microbial community development and unseen diversity recovery in inoculated sterile soil 总被引:1,自引:0,他引:1
Tom O. Delmont Davide Francioli Sophie Jacquesson Sandra Laoudi Alban Mathieu Joseph Nesme Maria Teresa Ceccherini Paolo Nannipieri Pascal Simonet Timothy M. Vogel 《Biology and Fertility of Soils》2014,50(7):1069-1076
Soil is considered as one of the most biodiverse environments on Earth; yet, the taxonomy, occurrence, and role of its different microbial populations are largely unknown. Here, two sterilized soils (from England and Italy) were inoculated with a subsample of their initial microbial communities and/or those from the other soil to study their microbial community evolution. This approach compared two driving factors (original community and soil physico-chemical characteristics) for microbial community definition. After 2 months of incubation and based on metagenomic datasets, the two inoculated communities (from an English grassland and an Italian forest) possessed similar functional and taxonomical structures when inoculated in the same sterile soil. For example, the newly colonized Italian soil was dominated by Actinobacteria related organisms (>66 % of the detected community) with a functional distribution independent of the inoculated soil origin. In addition, some of the organisms that dominated the different inoculated communities after 2 months were similar for a given sterile soil whether they came from the English grassland or the Italian forest, and they had not been detected in the original microbial community from either soil. Thus, similar microorganisms with low representation from the two distinct communities emerged in each sterilized soil, thus increasing the microbial diversity recovered from the microbial community of the donor soil. So far, these observations support the idea that different temperate soil microbial communities have different evenness due to environmental physico-chemical variations, yet have similar community composition (richness), and thus develop similarly when colonizing the same habitat. 相似文献
80.
Pascal Gentit René-Pierre Delbos Thierry Candresse Jean Dunez 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(5):485-494
A pathogen was transmitted from apricot trees showing symptoms of viral infection to GF305 peach seedlings which reacted by stunting, shortened internodes and chlorotic mottling. The agent was transmitted to cherry, apricot, peach and plum by grafting and to several herbaceous hosts by mechanical inoculation. Isometric nepovirus-like particles of 30–31 nm diameter extracted from infected Chenopodium quinoa sedimented as two peaks in sucrose gradients. These particles contained two single stranded RNAs of approximately 5.9 and 7.9 kb, and a single coat protein subunit of 53.7 kDa. No cross-reactions were observed with a number of nepoviruses infecting fruit trees. Inoculation of purified particles to herbaceous or woody hosts reproduced the same symptoms caused by the original isolate. Sequencing of a 2.2 kbp cDNA clone covering the 3 end of the small genomic RNA identified an open reading frame encoding a 317 aa N-truncated protein exhibiting significant similarities with the coat protein of nepoviruses. The 1257 nt long 3 non-coding region showed up to about 65% homology to the equivalent region of members of the subgroup C of nepoviruses. The properties of this pathogen do not match those of any previously described nepovirus. It should therefore be considered as a new member of the subgroup C of nepoviruses, for which the name of Apricot latent ringspot virus (ALRSV) is proposed.The nucleotide sequence reported in this work has been deposited in the EMBL databank under the accession number AJ278875. 相似文献