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71.
Raúl E. Cian Silvina R. Drago Fermín Sánchez de Medina Olga Martínez-Augustin 《Marine drugs》2015,13(8):5358-5383
Based on their composition, marine algae, and namely red seaweeds, are good potential functional foods. Intestinal mucosal barrier function refers to the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules. Here, we will first outline the component of seaweeds and will summarize the effects of these on the regulation of mucosal barrier function. Special attention will be paid to unique components of red seaweeds: proteins and derived peptides (e.g., phycobiliproteins, glycoproteins that contain “cellulose binding domains”, phycolectins and the related mycosporine-like amino acids) together with polysaccharides (e.g., floridean starch and sulfated galactans, such as carrageenans, agarans and “dl-hybrid”) and minerals. These compounds have been shown to exert prebiotic effects, to regulate intestinal epithelial cell, macrophage and lymphocyte proliferation and differentiation and to modulate the immune response. Molecular mechanisms of action of peptides and polysaccharides are starting to be elucidated, and evidence indicating the involvement of epidermal growth factor receptor (EGFR), insulin-like growth factor receptor (IGFR), Toll-like receptors (TLR) and signal transduction pathways mediated by protein kinase B (PKB or AKT), nuclear factor-κB (NF-κB) and mitogen activated protein kinases (MAPK) will also be summarized. The need for further research is clear, but in vivo experiments point to an overall antiinflammatory effect of these algae, indicating that they can reinforce membrane barrier function. 相似文献
72.
Sergey N. Golubev Andrei V. Schelud’ko Anna Yu. Muratova Oleg E. Makarov Olga V. Turkovskaya 《Water, air, and soil pollution》2009,198(1-4):5-16
Rhizobacteria possess a wide variety of qualities governing their pollutant-catabolic and rhizospheric competences. We investigated how the abilities to degrade phenanthrene and other polycyclic aromatic hydrocarbons (PAHs), to synthesize surfactants and the phytohormone indole-3-acetic acid (IAA), to be motile, and to perform chemotaxis toward phenanthrene and some potential root-exudate components were manifested in rhizobacteria isolated from oil-polluted sites. We observed that most of the examined rhizobacteria had the abilities under consideration and that in some strains, these were strongly affected by the bacterial environment. Only one strain—Sinorhizobium meliloti P221—exhibited increased PAH-degrading, surfactant-producing, and IAA-synthesizing activities, as well as distinct behavioral responses. We conclude that S. meliloti P221 can be used as a model to assess the contributions of all these activities to plant-inoculation-induced reduction in the soil PAH contents. This strain also may be useful for phytoremediation applications. 相似文献
73.
Alvarez J de Juan L Bezos J Romero B Sáez JL Marqués S Domínguez C Mínguez O Fernández-Mardomingo B Mateos A Domínguez L Aranaz A 《Veterinary microbiology》2009,135(3-4):389-393
Interferon-gamma (IFN-gamma) detection assay is being applied as an ancillary test to tuberculin tests in the diagnosis of bovine tuberculosis to detect the maximum number of infected animals. Among possible factors influencing the performance of tuberculosis-diagnostic tests, paratuberculosis, a widespread disease in Spain and other European countries, has been pointed out as a cause of false positive reactions. Still, its effect on the sensitivity of these tests in cattle has yet to be fully characterized. The impact of paratuberculosis in the apparent sensitivity of IFN-gamma assay was studied in a bullfighting cattle herd with a mixed tuberculosis-paratuberculosis infection, using culture of Mycobacterium bovis and Mycobacterium avium paratuberculosis as the gold standard to determine the infection status of every animal. A total of 218 animals were slaughtered and sampled for bacteriology after blood sampling. IFN-gamma assay showed a lower apparent sensitivity in animals with a mixed infection (50%) compared to all animals suffering tuberculosis (78.3%). This finding indicates that the presence of paratuberculosis in tuberculosis-infected herds could imply a serious impairment in the sensitivity of IFN-gamma detection test. 相似文献
74.
Laura Rodríguez-Turienzo Beatriz Sanmartín Olga Díaz 《Journal Of Aquatic Food Product Technology》2013,22(6):928-939
ABSTRACTThe effects of different egg white protein coatings on Atlantic salmon quality preservation after 4 months of frozen storage were evaluated. These coatings increased the yield of the fillets and protected them from lipid oxidation, providing better protection than glazing. Egg white protein coatings were better options than glazing to preserve salmon color during frozen storage. The best results were obtained with the application of coatings before freezing. No clear effects of the type and concentration of plasticizer in most quality parameters were found. Egg white protein + glycerol 2:1 applied before freezing was the best coating for frozen Atlantic salmon protection. 相似文献
75.
Maria Antonietta Demontis Santa Olga Cacciola Marcella Orrù Virgilio Balmas Valentina Chessa Bianca Elena Maserti Laura Mascia Francesco Raudino Gaetano Magnano di San Lio Quirico Migheli 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(4):339-351
Real-time PCR assays based on SYBR? Green I and TaqMan? technologies were developed for in planta detection and quantification of Phoma tracheiphila, the mitosporic fungus causing ‘mal secco’ disease on citrus. Primers and a hybridization probe were designed on the basis
of the internal transcribed spacer (ITS) region of the nuclear rRNA genes. The real-time PCR assays were compared with a classic
isolation method in two separate experiments carried out on 6 and 24 month-old sour orange seedlings, artificially inoculated
with a conidial suspension of the pathogen. Both technologies made it possible to follow the progression of infection by P. tracheiphila, enabling detection and quantification of the target fungus prior to the development of symptoms. The detection limit was
10 copies of the cloned target sequence and 15 pg of genomic DNA extracted from fungal spores. The values of the cycle threshold
(Ct) were linearly correlated with the concentration of the target DNA, indicating that the method is suitable as a qualitative
and quantitative assay. The presence of non-target fungal DNA had no effect on the specificity of the assay, but resulted
in a 10-fold reduction of sensitivity. Total inhibition of the reaction occurred when conidia of the target pathogen were
mixed with an organic soil substrate before extracting DNA using the standard protocol, while an alternative purification
kit resulted in a significant decrease in sensitivity. Compared to classic methods, real-time PCR proved faster and easier
to perform and showed a higher sensitivity. These results suggest that real-time PCR, based on both chemistries, has a great
potential for early diagnosis of ‘mal secco’ disease and for quantitative estimation of fungal growth within host tissue. 相似文献
76.
Mingming Yang Dmitri V. Mavrodi Olga V. Mavrodi Linda S. Thomashow David M. Weller 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(3):683-693
Four Neofabraea species are responsible for bull’s eye rot, which is an important postharvest disease of apples and pears. The species diversity of its causal agents in Europe has not been thoroughly explored using molecular genetic methods. Eighty-one Neofabraea isolates were obtained mostly from apples with bull’s eye rot symptoms in the Czech Republic over a two year period. The isolates were identified using PCR fingerprinting and DNA sequencing of the ITS rDNA region, the mitochondrial SSU rDNA and the β-tubulin and EF1α genes. The most common species was N. alba (89 %), followed by N. perennans (5 %) and N. kienholzii (5 %). This is the third published record of N. kienholzii in Europe. The species identity of the isolate CPPF507, which was placed close to N. kienholzii, remains unclear. EF1α was shown to be a suitable marker for the identification of species of the genus Neofabraea and was comparable to the previously used β-tubulin gene. Furthermore, the aggressiveness of individual species was compared and species distribution across Europe was summarized. N. perennans and isolate CPPF507 proved to be the most aggressive, whereas the least aggressive was N. kienholzii. Two N. alba isolates isolated from symptomless apple fruits and leaves were pathogenic to apples in the infection tests. 相似文献
77.
Olga Nikolaeva Marina Rozanova Mikhail Karpukhin 《Journal of Soils and Sediments》2017,17(4):1045-1053
Purpose
The objective of this research is to find out the spatial distribution of different traffic-related contaminants in urban topsoils across a highway (125,000 vehicles per day) in the city of Moscow, Russia.Materials and methods
The topsoils (0–3 cm depth) were sampled 1, 6, 10, 18, and 50 m perpendicular to the roadbed in three replicates 10 m apart. We analyzed total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), heavy metals in total and phyto-available forms (HM; Cu, Zn, and Pb), and deicing salts (DS; Cl?). The TPH were extracted with carbon tetrachloride and detected by spectrometry and PAH were extracted with methylene chloride, separated by high-performance liquid chromatography, and determined by fluorescence detector. Total HM were extracted by microwave acid digestion with aqua regia and phyto-available forms were extracted by NH4OAc and determined by inductively coupled plasma mass spectrometry. The DS were analyzed using an ion liquid chromatograph with a conductometric detector.Results and discussion
Heavy soil pollution was found within 1–6 m of the road. The TPH, B[a]P, and phyto-available HM concentrations exceeded permissible levels for Russia, while total HM and DS did not. The contaminant contents sharply decreased 10 m from the road. Within 10–50 m, they reached background levels, while PAH levels were elevated. We attribute this to the greater age of soils at 10–50 m than 1–6 m from the road. The different contaminant distribution patterns are attributed to their different transportation pathways: TPH, DS, and HM generally reach soils through road spray, splashes, melting snow moved from the road surface to roadsides, and aerosol sedimentation, whereas PAH are mainly transported as airborne particles and are thus able to reach more distant locations.Conclusions
Traffic-related soil pollution creates ecotoxicological and human-health risks. Distribution patterns vary by type of soil contaminant. The influence of the road on soil contamination was greatest within 10 m from the roadbed for TPH, HM, and DS and within 50 m for PAH. The increased PAH concentration levels with increased distance from the road highlights the importance of PAH monitoring in roadside soils.78.
Stavros Sakellariou Stergios Tampekis Fani Samara Athanassios Sfougaris Olga Christopoulou 《林业研究》2017,28(6):1107-1117
Forest ecosystems are our priceless natural resource and are a key component of the global carbon budget. Forest fires can be a hazard to the viability and sustainable management of forests with consequences for natural and cultural environments, economies, and the life quality of local and regional populations. Thus, the selection of strategies to manage forest fires, while considering both functional and economic efficiency, is of primary importance. The use of decision support systems (DSSs) by managers of forest fires has rapidly increased. This has strengthened capacity to prevent and suppress forest fires while protecting human lives and property. DSSs are a tool that can benefit incident management and decision making and policy, especially for emergencies such as natural disasters. In this study we reviewed state-of-the-art DSSs that use: database management systems and mathematical/economic algorithms for spatial optimization of firefighting forces; forest fire simulators and satellite technology for immediate detection and prediction of evolution of forest fires; GIS platforms that incorporate several tools to manipulate, process and analyze geographic data and develop strategic and operational plans. 相似文献
79.
80.
Tatiana A. Sorkina Alexander Yu. Polyakov Natalia A. Kulikova Anastasia E. Goldt Olga I. Philippova Alina A. Aseeva Alexey A. Veligzhanin Yan V. Zubavichus Denis A. Pankratov Eugene A. Goodilin Irina V. Perminova 《Journal of Soils and Sediments》2014,14(2):261-268