19 resultados para Safety Indicators

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Sodium rutin sulfate (SRS) is a sulfated rutin modified from the natural flavonol glycoside rutin. Here, we investigated its in vitro anti-HIV and -HSV activities and its cytotoxic profile. Fifty percent inhibitory concentration (IC50) values of SRS against HIV-1 X4 virus IIIB, HIV-1 R5 isolates Ada-M and Ba-L were 2.3 +/- 0.2, 4.5 +/- 2.0 and 8.5 +/- 3.8 mu M with a selectivity index (SI) of 563, 575 and 329, respectively. Its IC50 against primary R5 HIV-1 isolate from Yunnan province in China was 13.1 +/- 5.5 mu M, with a Sl of 197. In contrast, unsulfated rutin had no activity against any of the HIV-1 isolates tested. Further study indicated that SRS blocked viral entry and virus-cell fusion likely through interacting with the HIV- I envelope glycoprotein. SRS also demonstrated some activity against human herpes simplex virus (HSV) with an IC50 of 88.3 +/- 0.1 mu M and a Sl of 30. The 50% cytotoxicity concentration (CC50) of SRS was >3.0 mM, as determined in human genital ME 180, HeLa and primary human foreskin fibroblast cells. Minimum inhibitory concentration of SRS for vaginal lactobacilli was >3.0 mM. These results collectively indicate that SRS represents a novel candidate for anti-HIV-1/HSV microbicide development. (C) 2007 Elsevier B.V. All rights reserved.

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A comparative limnological study was carried out to present a snapshot of crustacean zooplankton communities and their relations to environmental factors to test whether there is a consistent relationship between crustacean biomass and trophic indicators among lake groups with similar trophic conditions. The study lakes showed a wide range of trophic status, with total phosphorus (TP) ranging from 0.008 to 1.448mgL(-1), and chlorophyll a from 0.7 to 146.1 mu g L-1, respectively. About 38 species of Crustacea were found, of which Cladocera were represented by 25 taxa (20 genera), and Copepoda by 13 taxa (I I genera). The most common and dominant species were Bosmina coregoni, Moina micrura, Diaphanosoma brachyurum, Cyclops vicinus, Thermocyclops taihokuensis, Mesocyclops notius and Sinocalanus dorrii. Daphnia was rare in abundance. Canonical correspondence analysis showed that except for four species (D. hyalina, S. dorrii, C. vicinus and M. micrura), almost all the dominant species had the same preference for environmental factors. Temperature, predatory cyclopoids and planktivorous fishes seem to be the key factors determining species distribution. TP was a relatively better trophic indicator than chlorophyll a to predict crustacean biomass. Within the three groups of lakes, however, there was no consistent relationship between crustacean biomass and trophic indicators. The possible reason might be that top-down and bottom-up control on crustaceans vary with lake trophic state. The lack of significant negative correlation between crustacean biomass and chlorophyll a suggests that there was little control of phytoplankton biomass by macrozooplankton in these shallow subtropical lakes. (c) 2007 Elsevier GmbH. All rights reserved.

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东北黑土区是我国重要的商品粮生产基地,在我国的粮食安全中发挥着重要作用。随着生产的发展,多种农用化学品进入黑土农田环境,使黑土面临着环境安全危机。因此,关于典型农用化学品单一与复合污染的生态毒性效应、解毒过程及与重金属复合污染及其稳定化过程等与黑土农田生态系统环境安全有关的科学问题的研究显得尤为迫切和重要。本文以该地区广泛使用的两种有机农药甲胺磷、乙草胺和普遍存在的重金属Cu为代表,研究了三种污染物对蛆妇的单一与复合毒性效应;探讨了复合污染及蛆叫活动对黑土中可交换态Cu和有机结合态Cu含量、乙草胺和甲胺磷残留含量随时间动态变化的影响及机理。结果表明,三种污染物对蛆妇具有潜在的危害,根据蛆妇单一毒性试验可推算出污染物的黑土环境安全浓度:复合污染的毒性机制复杂,不同浓度组合表现出协同、拮抗和部分加和等不同的联合毒性效应;复合污染与单一污染土壤中可交换态Cu含量呈最终趋于同一水平的波动变化;乙草胺和甲胺磷的复合作用和蛆叫活动扰动了土壤中有机结合态Cu含量随时间的动态变化;蚯蚓对铜有明显的富集作用,甲胺磷和乙草胺的复合能抑制蛆叫对Cu的富集。蚯蚓活动能促进乙草胺和甲胺磷的降解,加速其解毒过程进行。

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Dinoflagellate cyst records were analysed from four sediment cores from the inner Oslofjord. The cores covered the pre-industrial period, and the most important period of human population growth associated with industrial development of the region, from the mid-1800s to the present, including the reported development of cultural eutrophication. Comparisons between the cyst records and the known history of eutrophication suggest cyst signals that should prove useful for tracing the development of eutrophication. The eutrophication signal consisted of a doubling of total cyst concentration, and a marked increase in one species in particular,Lingulodinium machaerophorum(from <5 to around 50% of the assemblages) with increased eutrophication. In the core considered most representative of general water quality in the inner fjord, these trends reversed back to pre-industrial levels during the 1980s and 1990s when improved sewage treatment took effect.

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Variation in dinoflagellate cyst assemblages through the last approximately 300 years was studied in two sediment cores, one from the heavily polluted Frierfjord, and one from the adjoining, relatively unpolluted Brevikfjord, in order to docu1ent possible dinoflagellate responses to pollution. Changes in the cyst-flora were compared with historical information on the development of industry and also with geochemistry of the sediments, reflecting aspects of pollution. In the Frierfjord core, increasing pollution was accompanied by a decrease in cyst concentration, possibly reflecting reduced production, at least of dinoflagellates, and a shift toward more heterotrophic species, possibly reflecting reduced light penetration in the euphotic zone, or increased production of prey for the heterotrophs. These trends seem to have reversed as pollution decreased after about 1975, suggesting that cyst assemblages contain signals that may prove useful for tracing the development of pollution. Cyst assemblages in the Brevikfjord core only showed minor changes.