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61.
Casteleyn C Van den Broeck W Simoens P 《Veterinary immunology and immunopathology》2007,120(3-4):124-135
Tonsils form a first line of defence against foreign antigens and therefore play a key role in immunity. Since documented information about ovine tonsils is limited, a study was performed in which the morphological characteristics and the volume of lymphoid tissue present in each ovine tonsil were determined. The tonsils of five adult healthy sheep were examined histologically and the volumes were estimated using the Cavalieri method. The pharyngeal tonsil had a mean volume of 1296.1 ± 205.9 mm3 and was by far the largest ovine tonsil, followed by the paired palatine tonsil with a mean volume of 715.0 ± 110.5 mm3. The tonsil of the soft palate, the paired tubal and paraepiglottic tonsils and the lingual tonsil were much smaller with a mean volume of, respectively, 90.3 ± 24.9 mm3, 80.1 ± 24.3 mm3, 29.7 ± 11.8 mm3 and 10.1 ± 2.8 mm3. The folds and crypts of the pharyngeal and palatine tonsils were covered by a reticular and a non-reticular epithelium. Both tonsils were mainly composed of primary and secondary lymph follicles. The palatine tonsils contained 1–3 crypts with a few secondary infoldings. Lymphoid tissue in the tonsil of the soft palate was located at the nasopharyngeal (dorsal) side of the soft palate. The tubal tonsil was lined with a pseudostratified columnar ciliated epithelium and consisted of scattered lymphoid cells and lymph follicles. The paraepiglottic tonsil consisted of lymph follicles and aggregated lymphoid cells. Its overlying keratinized stratified squamous epithelium was folded and often heavily infiltrated by lymphocytes. The ovine lingual tonsil was not macroscopically visible and did not contain clearly distinguishable lymph follicles. It consisted of aggregations of lymphoid cells that were mainly located within the vallate lingual papillae. 相似文献
62.
Sugars in the form of monosaccharides, oligosaccharides, polysaccharides and glycoconjugates (glycoproteins, glycolipids) are vital components of infecting microbes and host cells, and are involved in cell signalling associated with modulation of inflammation in all integumental structures. Indeed, sugars are the molecules most commonly involved in cell recognition and communication. In skin, they are essential to epidermal development and homeostasis. They play important roles in microbial adherence, colonization and biofilm formation, and in virulence. Two groups of pathogen recognition receptors, C-type lectins (CTL) and their receptors (CTLR), and the Toll-like receptors enable the host to recognize pathogen-associated molecular patterns (PAMPs), which are mainly glycolipids. The CTLs can recognize a wide variety of bacteria, fungi and parasites and are important in phagocytosis and endocytosis. TLRs are expressed on the surfaces of a variety of cells, including keratinocytes, dendritic cells, monocytes and macrophages; they play a major role in innate immunity. Interaction of TLRs with PAMPs initiates a cascade of events leading to production of reactive oxygen intermediates, cytokines and chemokines, and promotes inflammation. Exogenous sugars can block carbohydrate receptors and competitively displace bacteria from attachment to cells, including keratinocytes. Thus sugars may provide valuable adjunctive anti-inflammatory and/or antimicrobial treatment. A promising approach is the use of a panel of carbohydrate derivatives with anti-adhesive efficacy against bacteria frequently involved in diseases affecting skin and other epithelia. More complete characterization of sugar receptors and their ligands will provide further keys to use of carbohydrates in immunomodulation and infection control in skin. 相似文献
63.
Kristof Brijs Jeroen A. Ingelbrecht Christophe M. Courtin Linda Schlichting Brian A. Marchylo Jan A. Delcour 《Cereal Chemistry》2004,81(3):361-368
The combined effects on pasta properties of 1) varying dosages of endoxylanases (EC 3.2.1.8) from Aspergillus aculeatus and Bacillus subtilis and 2) lower levels of water during pasta dough processing were studied. The A. aculeatus endoxylanase has high selectivity toward water‐extractable arabinoxylan (WE‐AX), whereas B. subtilis endoxylanase preferentially hydrolyzes water‐unextractable arabinoxylan (WU‐AX). Pasta was produced on a microscale (50.0 g) from the semolinas of both a strong (AC Navigator) and a moderately strong (AC Avonlea) durum wheat cultivar. The levels of added water in endoxylanase‐treated pastas were adjusted to obtain the same maximal farinograph consistencies as for the control pastas. The extruded pastas were dried with drying cycles at 40, 70, or 90°C. Apart from increasing levels of solubilized arabinoxylans, these treatments had little effect on the color, optimal cooking time, and firmness of the resulting pasta. High enzyme concentrations and low (40°C) drying temperature resulted in clearly or much less checked final products for the B. subtilis and A. aculeatus enzyme, respectively. Upon cooking, the enzymically formed low molecular weight arabinoxylans were retained better in the pasta strands than their equally low molecular weight arabinogalactan counterparts. 相似文献
64.
A new procedure was developed for the isolation of highly purified water‐extractable arabinoxylan (WE‐AX) from hull‐less barley flour. It included inactivation of endogenous enzymes, removal of proteins with silica gel, and removing β‐glucans, arabinogalactan‐peptides, and starch fragments by enzyme or solvent precipitation steps. WE‐AX recovered by this isolation procedure represented, on average, 47% of all WE‐AX present in hull‐less barley flour. Purified WE‐AX from flour of different hull‐less European barley cultivars contained 84.9–91.8% AX and showed small structural differences. The apparent peak molecular weight of the purified WE‐AX was 730,000–250,000, and the arabinose‐to‐xylose ratio was 0.55–0.63. Proton nuclear magnetic resonance spectroscopy showed that the levels of un‐, O‐2 mono‐, O‐3 mono‐, and O‐2,O‐3 disubstituted xylose residues were 59.1–64.7%, 8.2–10.0%, 5.7–10.6%, and 17.6– 23.1%, respectively, and the ratio of di‐ to monosubstituted xylose was 0.90–1.54. Both O‐3 mono‐ and disubstituted xylose residues occurred isolated or next to disubstituted xylose residues in the WE‐AX chain. 相似文献
65.
66.
Lorrie Gaschen Johann Lang Shuo Lin Manuele Adé-Damilano ré Busato Christophe W. Lombard Frédéric P. Gaschen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1999,13(4):346-356
A colony of cats affected with hypertrophic feline muscular dystrophy was used to study the occurrence of cardiomyopathy associated with dystrophin deficiency. Affected male and female cats, obligate carrier females, and unaffected healthy littermates were followed from 12 weeks of age into adulthood. Thoracic radiography, 2-D echocardiography, and 2-D-derived M-mode echocardiography were performed at 3-month intervals until 12 months of age and regularly thereafter. From 9 months of age, all affected cats had larger hearts than normal and carrier animals. Left ventricular wall thickness in systole and in diastole and interventricular septal thickness in systole were greater in affected cats 12 months and older when compared with normal or heterozygous animals (P < .05). The myocardium of affected cats was diffusely hypoechoic and thickened. Multiple hyperechoic foci were in the myocardium and papillary musculature. Shortening fraction was normal in all cats. Changes seen in carrier females included enlargement and hyperechogenicity of the papillary musculature after the age of 2 years. Gross and light microscopic examination revealed left ventricular wall thickening with multiple foci of mineralization in 2 of 5 hearts from dystrophin-deficient cats. Although approximately 10% of the normal dystrophin amount was present in the skeletal muscle, dystrophin could not be detected in the myocardium. Early onset concentric myocardial hypertrophy was present in all adult cats. Lesions were mainly localized in the myocardium of the left ventricular free wall and interventricular septum, papillary musculature, and the endocardium. Clinical signs of heart failure developed only infrequently in cats with hypertrophic feline muscular dystrophy. 相似文献
67.
Christian?Jeudy Marielle?Adrian Christophe?Baussard Céline?Bernard Eric?Bernaud Virginie?Bourion Hughes?Busset Lloren??Cabrera-Bosquet Frédéric?Cointault Simeng?Han Mickael?Lamboeuf Delphine?Moreau Barbara?Pivato Marion?Prudent Sophie?Trouvelot Hoai?Nam?Truong Vanessa?Vernoud Anne-Sophie?Voisin Daniel?Wipf Christophe?SalonEmail author 《Plant methods》2016,12(1):31
Background
In order to maintain high yields while saving water and preserving non-renewable resources and thus limiting the use of chemical fertilizer, it is crucial to select plants with more efficient root systems. This could be achieved through an optimization of both root architecture and root uptake ability and/or through the improvement of positive plant interactions with microorganisms in the rhizosphere. The development of devices suitable for high-throughput phenotyping of root structures remains a major bottleneck.Results
Rhizotrons suitable for plant growth in controlled conditions and non-invasive image acquisition of plant shoot and root systems (RhizoTubes) are described. These RhizoTubes allow growing one to six plants simultaneously, having a maximum height of 1.1 m, up to 8 weeks, depending on plant species. Both shoot and root compartment can be imaged automatically and non-destructively throughout the experiment thanks to an imaging cabin (RhizoCab). RhizoCab contains robots and imaging equipment for obtaining high-resolution pictures of plant roots. Using this versatile experimental setup, we illustrate how some morphometric root traits can be determined for various species including model (Medicago truncatula), crops (Pisum sativum, Brassica napus, Vitis vinifera, Triticum aestivum) and weed (Vulpia myuros) species grown under non-limiting conditions or submitted to various abiotic and biotic constraints. The measurement of the root phenotypic traits using this system was compared to that obtained using “classic” growth conditions in pots.Conclusions
This integrated system, to include 1200 Rhizotubes, will allow high-throughput phenotyping of plant shoots and roots under various abiotic and biotic environmental conditions. Our system allows an easy visualization or extraction of roots and measurement of root traits for high-throughput or kinetic analyses. The utility of this system for studying root system architecture will greatly facilitate the identification of genetic and environmental determinants of key root traits involved in crop responses to stresses, including interactions with soil microorganisms.68.
Luc Doyen Christophe Béné Michel Bertignac Fabian Blanchard Abdoul Ahad Cissé Catherine Dichmont Sophie Gourguet Olivier Guyader Pierre‐Yves Hardy Sarah Jennings Lorne Richard Little Claire Macher David Jonathan Mills Ahmed Noussair Sean Pascoe Jean‐Christophe Pereau Nicolas Sanz Anne‐Maree Schwarz Tony Smith Olivier Thébaud 《Fish and Fisheries》2017,18(6):1056-1072
Reconciling food security, economic development and biodiversity conservation is a key challenge, especially in the face of the demographic transition characterizing many countries in the world. Fisheries and marine ecosystems constitute a difficult application of this bio‐economic challenge. Many experts and scientists advocate an ecosystem approach to manage marine socio‐ecosystems for their sustainability and resilience. However, the ways by which to operationalize ecosystem‐based fisheries management (EBFM) remain poorly specified. We propose a specific methodological framework—viability modelling—to do so. We show how viability modelling can be applied using four contrasted case‐studies: two small‐scale fisheries in South America and Pacific and two larger‐scale fisheries in Europe and Australia. The four fisheries are analysed using the same modelling framework, structured around a set of common methods, indicators and scenarios. The calibrated models are dynamic, multispecies and multifleet and account for various sources of uncertainty. A multicriteria evaluation is used to assess the scenarios’ outcomes over a long time horizon with different constraints based on ecological, social and economic reference points. Results show to what extent the bio‐economic and ecosystem risks associated with the adoption of status quo strategies are relatively high and challenge the implementation of EBFM. In contrast, strategies called ecoviability or co‐viability strategies, that aim at satisfying the viability constraints, reduce significantly these ecological and economic risks and promote EBFM. The gains associated with those ecoviability strategies, however, decrease with the intensity of regulations imposed on these fisheries. 相似文献
69.
Christophe Dlye Frdric Laigret Marie-France Corio-Costet 《Pest management science》1997,51(3):309-314
Using a Random Amplified Polymorphic DNA (RAPD) assay, we investigated the genetic polymorphism existing among 62 European isolates of the grape powdery mildew fungus (Uncinula necator [Schw.] Burr.). Isolates overwintering as mycelium in buds were genetically distinct from isolates overwintering as ascospores, suggesting the existence of two genetically isolated powdery mildew populations, and consequently of two independent sources of inoculum in the vineyard. Isolates resistant to fungicides inhibiting sterol 14α-demethylation (DMIs) were found in both populations, suggesting that resistance to DMIs may arise independently in the two powdery mildew populations. A PCR assay targeting the gene encoding U. necator 14α-demethylase has been developed which will permit an early, specific detection of U. necator infections, and may be useful for spraying programmes. ©1997 SCI 相似文献
70.
Marília Hauser Carolina R.C. Doria Roberto V. Santos Aurea García‐Vasquez Marc Pouilly Christophe Pcheyran Emmanuel Ponzevera Gislene Torrente‐Vilara Sylvain Brail Jacques Panfili Audrey Darnaude Jean‐Franois Renno Carmen García‐Dvila Jesus Nuez Franck Ferraton Gladys Vargas Fabrice Duponchelle 《水产资源保护:海洋与淡水生态系统》2019,29(3):397-408