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81.
The green mussel Perna viridis was sampled from relatively clean and contaminated sites along the Kartanata–Kerala coast (south west coast of India) to study the tissue concentration of trace metals and biological responses to stress (biomarkers) such as sister chromatid exchange (SCE), chromosomal aberration, micronucleus (MN) test, hemic neoplasia (HN), Chromotest (Ames test) and comet assay. In general, mean tissue concentrations of toxic trace metals collected from 25 sampling sites were found to be below the World Health Organisation (WHO) permissible concentration given for seafood. The digestive gland extract of mussels from all 25 sampling sites showed negative reaction for mutagenic activity (Ames test) in the absence of metabolic activation. Very low levels of chromosomal aberration, SCE, MN, HN and comet cells were observed in mussels collected from both the urban associated and relatively clean sites. This study seems to indicate that that the coastal waters of Karnataka and Kerala are minimally contaminated with genotoxic and carcinogenic chemicals.Special Issue on Biomarkers of Marine Pollution and Bioremediation 相似文献
82.
Patricia B. Roth Michael J. Twiner Zhihong Wang Marie-Yasmine Bottein Dechraoui Gregory J. Doucette 《Toxicon》2007,50(8):1175-1191
Flavobacteriaceae (strain S03) and Cytophaga sp. (strain 41-DBG2) are algicidal bacteria active against the brevetoxin (PbTx)-producing, red tide dinoflagellate, Karenia brevis. Little is known about the fate of PbTx associated with K. brevis cells following attack by such bacteria. The fate and distribution of PbTx in K. brevis cultures exposed to these algicidal strains were thus examined by receptor binding assay and liquid chromatography/mass spectrometry (LC/MS) in three size fractions (>5, 0.22–5, <0.22 μm) over a 2-week time course. In control cultures, brevetoxin concentrations in the >5 μm particulate size fraction correlated with changes in cell density, whereas significant increases in dissolved (i.e., <0.22 μm) toxin were observed in the later stages of culture growth. Exposure of K. brevis to either of the two algicidal bacteria tested caused cell lysis, coinciding with a rapid decline in the >5 μm PbTX size fraction and a simultaneous release of dissolved toxin into the growth medium. Upon cell lysis, dissolved brevetoxin accounted for ca. 60% of total toxin and consisted of 51–82% open A-ring derivatives. Open A-ring PbTx-2 and PbTx-3 derivatives bound with lower affinity (approximately 22- and 57-fold, respectively) to voltage-gated sodium channels and were considerably less cytotoxic (86- and 142-fold, respectively) to N2A cells than their individual parent toxins (i.e., PbTx-2 and PbTx-3). These novel findings of changes in PbTx size-fractioned distribution and overall reduction in K. brevis toxicity following attack by algicidal bacteria improve our understanding of potential trophic transfer routes and the fate of PbTx during red tide events. Moreover, this information will be important to consider when evaluating the potential role of algicidal bacteria in harmful algal bloom (HAB) management strategies involving control of bloom populations. 相似文献
83.
目的:建立含人血白蛋白(HSA)的重组人睫状神经营养因子(rhCNTF)蛋白含量的 RP-HPLC 测定方法。方法:采用Symmetry300反相 C_4色谱柱(150mm×3.9mm,5μm);以0.1%三氟乙酸(TFA)水-0.1%TFA 乙腈分别组成流动相 A 和 B,以初始浓度比70:30进行终浓度比为10:90的31min 线性梯度洗脱,流速为0.6 mL·min~(-1),检测波长为280nm,柱温35℃。rhCNTF 主峰保留时间在27.7~28.4 min,HSA 保留时间在17.0~17.5min。结果:在线性范围为0.061~0.735 mg·mL~(-1)有良好的线性关系(r=0.9995)。结论:本方法简便、快捷,可用于含 HSA 的 rhCNTF 纯品的纯度检测及含量测定。 相似文献
84.
目的探讨间苯三酚注射液的细菌内毒素定量分析法。方法采用2005年版《中国药典(二部)》中的动态浊度法。结果供试品稀释50倍可以排除干扰,回收率在50%~200%范围内,试验结果与家兔升温法的一致。结论用动态文度法测定闯苯三酚注射液的细菌内毒素含量准确有效。 相似文献
85.
刘乃丰 《Acta pharmacologica Sinica》1994,(2)
本文用放射配体法观察了维拉帕米(Ver)对恒河猴肾上皮细胞LDL受体活性的影响,发现Ver以浓度和时间依赖的方式明显增强受体介导的结合和内移过程,对降解的影响不显著。Ver作用浓度为44 mmol·L~(-1)效应最明显。 相似文献
86.
Jitka Vostlov Adla Galandkov Bohumil Zlek Radka Lichnovsk Kateina íkov Jitka Ulrichov Alena Rajnochov Svobodov 《Journal of applied toxicology : JAT》2019,39(5):773-782
Human skin explant (HSE) seems to be a useful model for dermatological/cosmetic testing. HSE prepared from donor superfluous skin from plastic surgery operations is cheap and easily obtainable compared to reconstructed models. The HSE use, however, may be limited by the degeneration processes during cultivation. The aim was to monitor changes in metabolic activity and selected apoptotic, inflammatory and antioxidant parameters during 7 day cultivation. The significant changes were found in the superoxide dismutase‐2 level from day 5, glutathione S‐reductase level from day 6, metabolic activity and fibulin‐5 level from day 4, cyclooxygenase‐2, interleukin‐6 and interleukin‐10 from day 1 to 2. Other selected markers (lipid peroxidation products and glutathione level, glutathione S‐transferase, catalase, superoxide dismutase and glutathione S‐reductase activity, glutathione peroxidase and glutathione S‐reductase levels) were not modified significantly due to high inter‐individual variability of skin donors. The HSE microstructure as well as cytokeratin‐10 and proliferation marker Ki67 expression was also only minimally affected during cultivation. Collectively, the results demonstrate that HSE represents a good model for short‐term studies focused on the physical and chemical agent toxicity, protective potential of compounds or metabolic biotransformation. However, reduced metabolic activity, increased inflammation and the high inter‐individual variability and sensitivity of donors have to be taken into consideration. 相似文献
87.
88.
Yuqin Zhang Wei Xu Huang Li Xun Zhang Yufa Xia Kedan Chu Lidian Chen 《Journal of ethnopharmacology》2013
Ethnopharmacological relevance
Tripterygium wilfordii Hook f. is one of Traditional Chinese Medicines which is commonly used to treat rheumatoid arthritis (RA). The total alkaloids were the main constituent part of Tripterygium wilfordii Hook f. It has a great significance to study the effects of the total alkaloids of Tripterygium wilfordii Hook f. (ATW) on RA.Aim of the study
This paper aims at investigating the therapeutic effect of ATW on RA and its possible mechanism, and providing a theoretical and experimental basis for the clinical use of ATW.Materials and methods
The model of wistar rats of type II collagen-induced arthritis (CIA) was made, and the rats were perfused a stomach with ATW for 4 weeks continuously. Then the levels of interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-<alpha>, in the serum of CIA rats were detected by enzyme linked immunosorbent assay (ELISA), and the joint pathological section of CIA rats was observed by hematoxylin and eosin (HE) staining method and the expression of IL-6, IL-8, nuclear factor kappa B (NF-κB), TNF-α were measure by immunohistochemistry staining method.Results
Compared with model group, ATW could significantly reduce paw swelling and suppresse articular cartilage degenerated. The results also found that there was significant reduction levels of IL-6, IL-8 and TNF-α in serum of CIA rats treated with ATW and ATW inhibited the expression of IL-6, IL-8, NF-κB, TNF-α in synovial tissue.Conclusion
ATW not only could inhibit the symptom of CIA rats significantly but also could inhibit the production of IL-6, IL-8, TNF-α in serum and the expression of IL-6, IL-8, NF-κB and TNF-α in synovial tissue targeting the inflammatory. ATW would be a drug as a novel botanical drug for the treatment of RA. 相似文献89.
90.