Antitumor and Antimicrobial Potential of Bromoditerpenes Isolated from the Red Alga,Sphaerococcus coronopifolius     

Daniel Rodrigues  Celso Alves  André Horta  Susete Pinteus  Joana Silva  Gérald Culioli  Olivier P. Thomas  Rui Pedrosa 《Marine drugs》2015,13(2):713-726

Cancer and infectious diseases continue to be a major public health problem, and new drugs are necessary. As marine organisms are well known to provide a wide range of original compounds, the aim of this study was to investigate the bioactivity of the main constituents of the cosmopolitan red alga, Sphaerococcus coronopifolius. The structure of several bromoditerpenes was determined by extensive spectroscopic analysis and comparison with literature data. Five molecules were isolated and characterized which include a new brominated diterpene belonging to the rare dactylomelane family and named sphaerodactylomelol (1), along with four already known sphaerane bromoditerpenes (2–5). Antitumor activity was assessed by cytotoxicity and anti-proliferative assays on an in vitro model of human hepatocellular carcinoma (HepG-2 cells). Antimicrobial activity was evaluated against four pathogenic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. Compound 4 exhibited the highest antimicrobial activity against S. aureus (IC₅₀ 6.35 µM) and compound 5 the highest anti-proliferative activity on HepG-2 cells (IC₅₀ 42.9 µM). The new diterpene, sphaerodactylomelol (1), induced inhibition of cell proliferation (IC₅₀ 280 µM) and cytotoxicity (IC₅₀ 720 µM) on HepG-2 cells and showed antimicrobial activity against S. aureus (IC₅₀ 96.3 µM).  相似文献   

Salinity and organic amendment effects on methane emission from a rain-fed saline paddy field   总被引：1，自引：0，他引：1  

Sakulrat SUPPARATTANAPAN  Patcharee SAENJAN  Cécile QUANTIN  Jean Luc MAEGHT  Olivier GRÜNBERGER 《Soil Science and Plant Nutrition》2009,55(1):142-149

  相似文献   

Reliability of an expert-based runoff and erosion model: Application of STREAM to different environments     

Olivier Evrard  Olivier Cerdan  Bas van Wesemael  Mehdi Chauvet  Yves Le Bissonnais  Damien Raclot  Karel Vandaele  Patrick Andrieux  Charles Bielders 《CATENA》2009

During the last decades, the European loess belt has been confronted with a significant increase in environmental problems due to erosion on agricultural land. Spatially distributed runoff and erosion models operating at the catchment scale are therefore needed to evaluate the impact of potential mitigation measures. Expert-based models offer an alternative solution to process-based and empirical models, but their decision rules are only valid for the local conditions for which they have been derived. The STREAM model, which was developed in Normandy (France), has been applied in two Belgian catchments having a similar soil texture, as well as in a catchment of southern France differing by soil, land use and climate characteristics. The performance of hydrological models can be assessed for instance by calculating the Nash–Sutcliffe efficiency criterion (E_NS). When applied to Belgium, the model results are satisfactory to good after an adaptation of the decision rules (0.90 < E_NS < 0.93 for runoff predictions and 0.85 < E_NS < 0.89 for erosion predictions). Given the important environmental differences between Normandy and southern France, the model rules were also adapted for application in the latter environment. Unfortunately, the quality of runoff predictions was insufficient to simulate erosion in southern France. In conclusion, STREAM is a reliable model providing satisfactory runoff and erosion predictions in the regions where hortonian overland flow dominates. Nevertheless, an adaptation of decision rules based on local multi-scale (plot, field, catchment) data is needed, before running the model. STREAM can then serve as a decision support tool to design for instance flood control measures.  相似文献   

State-of-the-art review of goat TSE in the European Union, with special emphasis on PRNP genetics and epidemiology     

Gabriele Vaccari  Cynthia H. Panagiotidis  Cristina Acin  Simone Peletto  Francis Barillet  Pierluigi Acutis  Alex Bossers  Jan Langeveld  Lucien van Keulen  Theodoros Sklaviadis  Juan J. Badiola  Olivier Andr��oletti  Martin H. Groschup  Umberto Agrimi  James Foster    Wilfred Goldmann 《Veterinary research》2009,40(5)

Scrapie is a fatal, neurodegenerative disease of sheep and goats. It is also the earliest known member in the family of diseases classified as transmissible spongiform encephalopathies (TSE) or prion diseases, which includes Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE), and chronic wasting disease in cervids. The recent revelation of naturally occurring BSE in a goat has brought the issue of TSE in goats to the attention of the public. In contrast to scrapie, BSE presents a proven risk to humans. The risk of goat BSE, however, is difficult to evaluate, as our knowledge of TSE in goats is limited. Natural caprine scrapie has been discovered throughout Europe, with reported cases generally being greatest in countries with the highest goat populations. As with sheep scrapie, susceptibility and incubation period duration of goat scrapie are most likely controlled by the prion protein (PrP) gene (PRNP). Like the PRNP of sheep, the caprine PRNP shows significantly greater variability than that of cattle and humans. Although PRNP variability in goats differs from that observed in sheep, the two species share several identical alleles. Moreover, while the ARR allele associated with enhancing resistance in sheep is not present in the goat PRNP, there is evidence for the existence of other PrP variants related to resistance. This review presents the current knowledge of the epidemiology of caprine scrapie within the major European goat populations, and compiles the current data on genetic variability of PRNP.  相似文献   

UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-malvidin 3-glucoside pigments in aqueous solution: structural transformations and molecular complexation with chlorogenic acid     

Dueñas M  Salas E  Cheynier V  Dangles O  Fulcrand H 《Journal of agricultural and food chemistry》2006,54(1):189-196

The physicochemical properties of 8,8-methylmethine catechin-malvidin 3-O-glucoside isomers, commonly referred to as catechin-ethyl-malvidin 3-O-glucoside, have been studied in aqueous solutions and compared with those of the parent anthocyanin (malvidin 3-O-glucoside). The hydration and acidity constants (pKh and pKa) of the catechin-ethyl-malvidin 3-O-glucoside pigments and malvidin 3-O-glucoside were determined by UV-visible spectroscopic measurements. The ethyl-linked catechin-malvidin 3-O-glucoside pigments present higher stability toward hydration than the parent anthocyanin. The high resistance of these ethyl-linked pigments toward the hydration is related to the self-association that offers optimal protection from the nucleophilic attack of water. Moreover, the ethyl link may confer to the molecule enough flexibility to undergo intramolecular interaction, further protecting it from hydration and bisulfite discoloration. In the wine pH range (3.2-4.0), due to the low pKa and high pKh values, the ethyl-linked pigments are present as colored forms (flavylium cation and quinonoid bases).  相似文献   

Selection of a monoclonal antibody for detection of gliadins and glutenins: A step towards reliable gluten quantification     

Olivier Tranquet  Colette LarréSandra Denery-Papini 《Journal of Cereal Science》2012

  相似文献   

EXTERNALITIES,INSTITUTIONS AND THE LOCATION CHOICES OF SHELLFISH PRODUCERS: THE CASE OF BLUE MUSSEL FARMING IN THE MONT-SAINT-MICHEL BAY (FRANCE)     

Rémi Mongruel  Olivier Thébaud 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):163-181

ABSTRACT

Most marine aquaculture activities remain strongly dependent on coastal ecosystems. In the case of shellfish farming, this dependency is related mainly to water quality and to the various ecological interactions resulting from the dynamics of coastal food webs. Such ecological constraints have influenced the overall evolution of blue mussel farming in the Mont-Saint-Michel Bay, leading producers to negotiate collective arrangements regarding production capacity and techniques and to develop production strategies at the farm level. This article presents an analysis of the location choices of mussel farmers in the Mont-Saint-Michel Bay based on an empirical investigation conducted in 2002. A typology of farms with respect to their land structure is developed in which some farms choose to concentrate their activity in a single part of the bay while others distribute their activity more widely. Determinants of the location choices of each farm category, including distance to port, natural productivity differentials, and predation of mussel stocks, are analyzed. The role of the institutional arrangements allowing mussel farmers to develop these location strategies is also discussed.  相似文献   

Social vulnerability to climate‐induced natural disasters: Cross‐provincial evidence from Vietnam     

Olivier Rubin 《Asia Pacific viewpoint》2014,55(1):67-80

This paper conducts an analysis of the socioeconomic determinants of Vietnam's cross‐provincial variations in natural disaster vulnerability. The purpose is twofold: (i) to capture disaggregated vulnerability variations normally obscured by national statistics, thereby providing more nuanced insights into Vietnam's vulnerability to natural disasters; and (ii) to take advantage of the fact that the overall political system and key institutional structures to a large extent are constant across Vietnam's provinces, which makes the analysis a novel addition to the many disaster studies based on cross‐national variations. The paper's analysis indicates that much of Vietnam's cross‐provincial variations in natural disaster fatalities and economic costs can be explained by differences in key socioeconomic factors. High provincial rates of inequality, poverty and infant mortality, for instance, appear to drive up natural disaster fatalities. Local adaptation efforts should focus as much on these broader socioeconomic dimensions as they focus on the geophysical susceptibility to natural hazards of individual areas.  相似文献   

Whiptail Stingray Injury     

Simon Laurent  Olivier Martinet  Helene Cuq  Alain Rind  Philippe Durasnel  Claire Lenne  Renaud Blondé 《The Forestry Chronicle》2018,29(2):243-247

  相似文献   

Evaluation of T2‐weighted versus short‐tau inversion recovery sagittal sequences in the identification and localization of canine intervertebral disc extrusion with low‐field magnetic resonance imaging          下载免费PDF全文

Daniel Housley  Abby Caine  Giunio Cherubini  Olivier Taeymans 《Veterinary radiology & ultrasound》2017,58(4):433-443

Sagittal T2‐weighted sequences (T2‐SAG) are the foundation of spinal protocols when screening for the presence of intervertebral disc extrusion. We often utilize sagittal short‐tau inversion recovery sequences (STIR‐SAG) as an adjunctive screening series, and experience suggests that this combined approach provides superior detection rates. We hypothesized that STIR‐SAG would provide higher sensitivity than T2‐SAG in the identification and localization of intervertebral disc extrusion. We further hypothesized that the parallel evaluation of paired T2‐SAG and STIR‐SAG series would provide a higher sensitivity than could be achieved with either independent sagittal series when viewed in isolation. This retrospective diagnostic accuracy study blindly reviewed T2‐SAG and STIR‐SAG sequences from dogs (n = 110) with surgically confirmed intervertebral disc extrusion. A consensus between two radiologists found no significant difference in sensitivity between T2‐SAG and STIR‐SAG during the identification of intervertebral disc extrusion (T2‐SAG: 92.7%, STIR‐SAG: 94.5%, P = 0.752). Nevertheless, STIR‐SAG accurately identified intervertebral disc extrusion in 66.7% of cases where the evaluation of T2‐SAG in isolation had provided a false negative diagnosis. Additionally, one radiologist found that the parallel evaluation of paired T2‐SAG and STIR‐SAG series provided a significantly higher sensitivity than T2‐SAG in isolation, during the identification of intervertebral disc extrusion (T2‐SAG: 78.2%, paired T2‐SAG, and STIR‐SAG: 90.9%, P = 0.017). A similar nonsignificant trend was observed when the consensus of both radiologists was taken into consideration (T2‐SAG: 92.7%, paired T2‐SAG, and STIR‐SAG = 97.3%, P = 0.392). We therefore conclude that STIR‐SAG is capable of identifying intervertebral disc extrusion that is inconspicuous in T2‐SAG, and that STIR‐SAG should be considered a useful adjunctive sequence during preliminary sagittal screening for intervertebral disc extrusion in low‐field magnetic resonance.  相似文献