Antiplatelet and Anticoagulant Effects of Diterpenes Isolated from the Marine Alga,Dictyota menstrualis     

Laura de Andrade Moura  Ana Carolina Marqui de Almeida  Thaisa Francielle Souza Domingos  Fredy Ortiz-Ramirez  Diana Negr?o Cavalcanti  Valéria Laneuville Teixeira  André Lopes Fuly 《Marine drugs》2014,12(5):2471-2484

Cardiovascular diseases represent a major cause of disability and death worldwide. Therapeutics are available, but they often have unsatisfactory results and may produce side effects. Alternative treatments based on the use of natural products have been extensively investigated, because of their low toxicity and side effects. Marine organisms are prime candidates for such products, as they are sources of numerous and complex substances with ecological and pharmacological effects. In this work, we investigated, through in vitro experiments, the effects of three diterpenes (pachydictyol A, isopachydictyol A and dichotomanol) from the Brazilian marine alga, Dictyota menstrualis, on platelet aggregation and plasma coagulation. Results showed that dichotomanol inhibited ADP- or collagen-induced aggregation of platelet-rich plasma (PRP), but failed to inhibit washed platelets (WP). In contrast, pachydictyol A and isopachydictyol A failed to inhibit the aggregation of PRP, but inhibited WP aggregation induced by collagen or thrombin. These diterpenes also inhibited coagulation analyzed by the prothrombin time and activated partial thromboplastin time and on commercial fibrinogen. Moreover, diterpenes inhibited the catalytic activity of thrombin. Theoretical studies using the Osiris Property Explorer software showed that diterpenes have low theoretical toxicity profiles and a drug-score similar to commercial anticoagulant drugs. In conclusion, these diterpenes are promising candidates for use in anticoagulant therapy, and this study also highlights the biotechnological potential of oceans and the importance of bioprospecting to develop medicines.  相似文献   

Growth hormone (GH) and reproduction: a review   总被引：5，自引：0，他引：5  

Florence Le Gac  Odile Blaise  Alex Fostier  Pierre-Yves Le Bail  Maurice Loir  Brigitte Mourot  Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232

Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.  相似文献   

Staining of heterochromatin bands and the determination of rye chromosomes in triticale (wheat × rye hybrid)     

Val T. Sapra  Moira D. Stewart 《Euphytica》1980,29(2):497-509

Summary Fifteen lines of triticale were studied using the C-banding staining method. A typical, complete chromosomal complement was found in 11 lines, while the remaining lines demonstrated some variations. A slight modification in the technique is discussed.Supported in part by CSRS/USDA Grant No. 801-15-03A.  相似文献   

Relationships between biochemical attributes (non-structural carbohydrates and phenolics) and natural durability against fungi in dry teak wood (Tectona grandis L. f.)     

Florence Bobelé Niamké  Nadine Amusant  Jean-Paul Charpentier  Gilles Chaix  Yves Baissac  Nabila Boutahar  Augustin Amissa Adima  Séraphin Kati-Coulibaly  Christian Jay-Allemand 《Annals of Forest Science》2011,68(1):201-211

• Introduction   

Non-structural carbohydrates and phenolic compounds are implicated in the natural durability of wood. In order to find the chemical traits of natural durability in teak wood, the radial distribution of phenolics compounds and non-structural carbohydrates were studied in trees ranked by contrasting natural durability class against Antrodia sp.  相似文献   

In search of a maize ideotype for cell wall enzymatic degradability using histological and biochemical lignin characterization   总被引：1，自引：0，他引：1  

Méchin V  Argillier O  Rocher F  Hébert Y  Mila I  Pollet B  Barriére Y  Lapierre C 《Journal of agricultural and food chemistry》2005,53(15):5872-5881

Grass cell wall degradability is conventionally related to the lignin content and to the ferulic-mediated cross-linking of lignins to polysaccharides. To better understand the variations in degradability, 22 maize inbred lines were subjected to image analyses of Fasga- and M?ule-stained stem sections and to chemical analyses of lignins and p-hydroxycinnamic acids. For the first time, the nearness of biochemical and histological estimates of lignin levels was established. Combination of histological and biochemical traits could explain 89% of the variations for cell wall degradability and define a maize ideotype for cell wall degradability. In addition to a reduced lignin level, such an ideotype would contain lignins richer in syringyl than in guaiacyl units and preferentially localized in the cortical region rather than in the pith. Such enrichment in syringyl units would favor wall degradability in grasses, contrary to dicots, and could be related to the fact that grass syringyl units are noticeably p-coumaroylated. This might affect the interaction capabilities of lignins and polysaccharides.  相似文献   

Synthesis and stable isotope dilution assay of ethanethiol and diethyl disulfide in wine using solid phase microextraction. Effect of aging on their levels in wine     

Belancic Majcenovic A  Schneider R  Lepoutre JP  Lempereur V  Baumes R 《Journal of agricultural and food chemistry》2002,50(23):6653-6658

Ethanethiol and diethyl disulfide (DEDS) most often occurred at levels above their olfactive threshold in wines with nauseous sulfur-linked smells. As ethanethiol is very oxidizable and chemically reactive, a stable isotopic dilution analysis of both ethanethiol and its disulfide in wines using solid phase microextraction and GC-MS was developed. The latter involved the determination of the proportion of DEDS formed by oxidation of the thiol during the analysis conditions, which was obtained by the use of two differently labeled disulfide standards. An original synthesis of labeled ethanethiol standards in conditions minimizing oxidation was developed, and the corresponding labeled diethyl disulfides were obtained from these thiols. This analytical method was used to follow the levels of these sulfur compounds during aging in a young red wine spiked with ethanethiol and added with enological tannins, with or without oxygen addition. The total levels of these two sulfur compounds were shown to decrease steadily after 60 days of aging, up to 83%. The effect of oxygen sped this decrease, but the effect of enological tannins was very slight. Residual ethanethiol was detected in its disulfide form from approximately 36% in the nonoxygenated wines to 69% in the oxygenated samples.  相似文献   

The role of foreign assistance and commercial interests in the exploitation of the Sundarbans     

Florence E. McCarthy 《Agriculture and Human Values》1990,7(2):52-60

This paper analyzes resource utilization of the Sundarbans in terms of the contradictory issues and pressures generated by foreign assistance and commercial interests in Bangladesh. In the paper, the historical legacy of resource definition and use that shaped the development of forest policy under the British is considered. In addition, the critical role of the state and the interests and pressures on the Government are explored as these shape the larger context in which current natural resource policy is generated and maintained. Three areas of potential conflict between current devlopment policy and resource management control are noted. They are 1) the privatization of production and resource exploitation in contrast to common property resource use, 2) the need to meet foreign exchange requirements versus local user interests, and 3) commercial versus local user interests.The paper argues that national and international fiscal and economic constraints operate to favor commercial interests and natural resource exports at the cost of policies that emphasize an active approach to the generation and preservation of renewable resources such as the Sundarbans.  相似文献   

Atmospheric methane and nitrous oxide of the Late Pleistocene from Antarctic ice cores     

Spahni R  Chappellaz J  Stocker TF  Loulergue L  Hausammann G  Kawamura K  Flückiger J  Schwander J  Raynaud D  Masson-Delmotte V  Jouzel J 《Science (New York, N.Y.)》2005,310(5752):1317-1321

The European Project for Ice Coring in Antarctica Dome C ice core enables us to extend existing records of atmospheric methane (CH4) and nitrous oxide (N2O) back to 650,000 years before the present. A combined record of CH4 measured along the Dome C and the Vostok ice cores demonstrates, within the resolution of our measurements, that preindustrial concentrations over Antarctica have not exceeded 773 +/- 15 ppbv (parts per billion by volume) during the past 650,000 years. Before 420,000 years ago, when interglacials were cooler, maximum CH4 concentrations were only about 600 ppbv, similar to lower Holocene values. In contrast, the N2O record shows maximum concentrations of 278 +/- 7 ppbv, slightly higher than early Holocene values.  相似文献   

Stable carbon cycle-climate relationship during the Late Pleistocene   总被引：2，自引：0，他引：2  

Siegenthaler U  Stocker TF  Monnin E  Lüthi D  Schwander J  Stauffer B  Raynaud D  Barnola JM  Fischer H  Masson-Delmotte V  Jouzel J 《Science (New York, N.Y.)》2005,310(5752):1313-1317

A record of atmospheric carbon dioxide (CO2) concentrations measured on the EPICA (European Project for Ice Coring in Antarctica) Dome Concordia ice core extends the Vostok CO2 record back to 650,000 years before the present (yr B.P.). Before 430,000 yr B.P., partial pressure of atmospheric CO2 lies within the range of 260 and 180 parts per million by volume. This range is almost 30% smaller than that of the last four glacial cycles; however, the apparent sensitivity between deuterium and CO2 remains stable throughout the six glacial cycles, suggesting that the relationship between CO2 and Antarctic climate remained rather constant over this interval.  相似文献   

Antifungal effects of iron sulfate on grapevine fungal pathogens     

Pierrette Fleurat-Lessard  Fabienne Dédaldéchamp  Florence Thibault  Emile Béré  Gabriel Roblin 《Scientia Horticulturae》2011

The present study aimed to determine the most efficient experimental conditions of iron sulfate use leading to optimal inhibition in the development of fungal pathogens. Assays have been focused on fungal species inducing severe grapevine diseases. FeSO₄ directly inhibited the in vitro mycelial growth of Botrytis cinerea, Eutypa lata, Phaeomoniella chlamydospora, Phaeoacremonium aleophilum, Diplodia seriata, and Neofusicoccum parvum with variable efficiency in the range of 0.5–10 mM. The development was always completely inhibited at 20 mM. This inhibitory effect was greatly increased at acidic pH values. The anionic moiety of the molecule was of importance since bromide, chloride and sulfate were highly active, whereas acetate and oxalate showed a small effect. Electron microscope observations on E. lata and B. cinerea showed that a treatment with FeSO₄ induced dramatic changes in the hyphal organization leading to cell death. No toxicity was observed on grapevine leaves following repeated FeSO₄ sprays in the antifungal concentration range. Therefore, FeSO₄ may be proposed to effectively replace the long-term pollutant use of CuSO₄ as an antifungal agent, with the additional advantage of iron being an important plant micronutrient.  相似文献