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991.
Cloning, characterization, and biological function analysis of the SidT2 gene from Siniperca chuatsi
Ren R Xu X Lin T Weng S Liang H Huang M Dong C Luo Y He J 《Developmental and comparative immunology》2011,35(6):692-701
The systemic RNA interference defective protein (SID)-1 plays an important role in dsRNA uptake in cells. We identified the ScSidT2 gene from the mandarin fish (Siniperca chuatsi), which is the first-studied SID-1 homolog in fish. ScSidT2 mRNA is 3380 bp long and contains a 2568-bp open reading frame that encodes an 855-amino-acid protein with an N-terminal signal peptide and ten putative transmembrane domains. Tissue distribution profile in healthy fish and expression profiles of ScSidT2 in infectious spleen and kidney necrosis virus (ISKNV)-infected fish were analyzed. Overexpression of the ScSidT2 protein in fathead minnow (FHM) epithelial cells could remarkably increase the uptake of exogenous dsRNA. In tiger frog virus (TFV)-infected FHM cells, overexpression of ScSidT2 could suppress virus production, and this mechanism could be significantly enhanced by adding virus-specific dsRNA. In mandarin fish fry cells, ISKNV infection and reproduction could be promoted when the ScSidT2 protein was neutralized with specific antisera. These results suggest that ScSidT2 could be associated with the host's antiviral defense mechanism. 相似文献
992.
Review: Do engineered nanoparticles pose a significant threat to the aquatic environment? 总被引:1,自引:0,他引:1
《Critical reviews in toxicology》2013,43(7):653-670
Nanotechnology is a rapidly growing industry of global economic importance, exploiting the novel characteristics of materials manufactured at the nanoscale. The properties of engineered nanoparticles (ENPs) that make them useful in a wide range of industrial applications, however, have led to concerns regarding their potential impact on human and environmental health. The aquatic environment is particularly at risk of exposure to ENPs, as it acts as a sink for most environmental contaminants. This paper critically evaluates what is currently known about sources and discharge of ENPs to the aquatic environment and how the physicochemical characteristics of ENPs affect their fate and behaviour and thus availability for uptake into aquatic organisms, and assesses reported toxicological effects. Having reviewed the ecotoxicological information, the conclusion is that whilst there are data indicating some nanoparticles have the potential to induce harm in exposed aquatic organisms, there is insufficient evidence for harm, for known/modelled environmental concentrations for almost all ENPs considered. This conclusion, however, must be balanced by the fact that there are significant gaps in our understanding on the fate and behaviour of ENPs in the aquatic environment. Greater confidence in the assessments on ENP impacts in aquatic systems to enable effective comparisons across studies urgently requires more standardised approaches for ENP hazard identification, and critically, more thorough characterisations on the exposed particles. There is also an urgent need for the advancement of tools and techniques that can accurately quantify and visualise uptake of nanoparticles into biological tissues. 相似文献
993.
Anna L. Choi Sylvaine Cordier Pál Weihe Philippe Grandjean 《Critical reviews in toxicology》2013,43(10):877-893
In observational studies, the presence of a confounding factor can distort the true association between an exposure and a toxic-effect outcome, if the confounding variable is not controlled for in the study design or analysis phase. While confounding is often assumed to occur in the same direction as the toxicant exposure, the relationship between the benefits and risks associated with fish and seafood consumption is a classic example of negative confounding: the exposure to methylmercury occurs with fish and seafood, which are also associated with beneficial nutrients, and the signs of mercury toxicity are thereby counteracted. Mercury and nutrients may affect the same epidemiological outcomes, but most studies addressing one of them have ignored the potential for negative confounding by the other. This article reviews the existing evidence of effects of both nutrient and contaminant intakes as predictors of neurodevelopmental and cardiovascular outcomes. Substantial underestimation of the effects of mercury toxicity and of fish benefits occurs from the lack of confounder adjustment and imprecision of the exposure parameters. Given this inherent bias in observational studies, regulatory agencies should reconsider current dietary advice in order to provide better guidance to consumers in making prudent choices to maintain a nutritious diet with seafood that is low in mercury concentrations. Attention should also be paid to the occurrence of negative confounding in other connections. 相似文献
994.
Hanne Skou Jrgensen Ivar Anders Eide Trond Jenssen Anders sberg Jens Bollerslev Kristin Godang Anders Hartmann Erik Berg Schmidt My Svensson 《Nutrients》2021,13(7)
Kidney transplant recipients are at high risk of progressive bone loss and low-energy fractures in the years following transplantation. Marine n-3 polyunsaturated fatty acids (n-3 PUFA) supplementation may have beneficial effects on bone strength. The Omega-3 fatty acids in Renal Transplantation (ORENTRA) trial was an investigator initiated, randomized, placebo-controlled trial investigating the effects of marine n-3 PUFA supplementation after kidney transplantation. Effects of supplementation on bone mineral density (BMD) and calcium metabolism were pre-defined secondary endpoints. Adult kidney transplant recipients (n = 132) were randomized to 2.6 g marine n-3 PUFA supplement or olive oil (control) from 8 to 52 weeks post-transplant. Dual energy X-ray absorptiometry was performed to assess changes in bone mineral density of hip, spine, and forearm, as well as trabecular bone score (TBS) of the lumbar spine. Student’s t test was used to assess between-group differences. There were no differences in ΔBMD between the two groups (intervention vs. control) at lumbar spine (−0.020 ± 0.08 vs. −0.007 ± 0.07 g/cm², p = 0.34), total hip (0.001 ± 0.03 vs. −0.005 ± 0.04, p = 0.38), or other skeletal sites in the intention-to-treat analyses. There was no difference in the change in TBS score (0.001 ± 0.096 vs. 0.009 ± 0.102, p = 0.62). Finally, no effect on biochemical parameters of mineral metabolism was seen. Results were similar when analyzed per protocol. In conclusion, we found no significant effect of 44 weeks of supplementation with 2.6 g of marine n-3 PUFA on BMD in kidney transplant recipients. 相似文献
995.
Dynamic skeletogenesis in fishes: Insight of exercise training on developmental plasticity 总被引:1,自引:0,他引:1
Background: Through developmental and evolutionary time, organisms respond variably to their environment not only in terms of size and shape but also in terms of timing. Developmental plasticity can potentially act on various aspects of the timing of developmental events (i.e., appearance, cessation, duration, sequence). In this study, we address the developmental plasticity of median fin endoskeleton by using exercise training on newly‐hatched Arctic charr (Salvelinus alpinus). Results: Developmental progress of cartilage formation (i.e., chondrification) in all fins is less influenced than ossification by an increase of water velocity. The most responsive elements, meaning those elements with greater onset plasticity owing to a water velocity increase, differ in terms of early versus late developmental events. The most responsive elements are those that chondrify and to a greater extent ossify later in the development. Conclusions: Plasticity is documented for the timing of appearance (i.e., onset) and the timing of transition from cartilage to bone (i.e., transitions of skeletal states) rather than the order of events within a sequence. Similarities of plastic response in developmental patterns could be used as a powerful criterion to strengthen the identification of phenotypic modules. Developmental Dynamics 241:1507–1524, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
996.
Ethnopharmacological Relevence
Herbal drugs are gaining worldwide prominence due to their distinct advantages. Developing countries have started exploring the ethnopharmacological approach of drug discovery and have begun to file patents on herbal drugs. The expansion of R&D in Indian herbal research organizations and presence of manufacturing units at non-Indian sites is an indication of the capability to develop new products and processes. The present study attempts to identify innovations in the Indian herbal drug sector by analyzing the patenting trends in India, US and EU.Methodology
Based on key word and IPC based search at the IPO, USPTO, Esp@cenet and WIPO databases, patent applications and grant in herbal drugs by Indian applicants/assignees was collected for the last ten years (from 1st January 2001 to 31st October 2010). From this collection patents related to human therapeutic use only were selected. Analysis was performed to identify filing trends, major applicants/assignees, disease area and major plant species used for various treatments.Result
There is a gradual increase in patent filing through the years. In India, individual inventors have maximum applications and grants. CSIR, among research organizations and Hindustan Unilever, Avesthagen, Piramal Life Science, Sahajanand Biotech and Indus Biotech among the companies have the maximum granted patents in India, US and EU respectively. Diabetes, cancer and inflammatory disorders are the major areas for patenting in India and abroad. Recent patents are on new herbal formulations for treatment of AIDS, hepatitis, skin disorders and gastrointestinal disorders.Conclusion
A majority of the herbal patents applications and grants in India are with individual inventors. Claim analysis indicates that these patents include novel multi-herb compositions with synergistic action. Indian research organizations are more active than companies in filing for patents. CSIR has maximum numbers of applications not only in India but also in the US and EU. Patents by research organizations and herbal companies are on development of new processes for active compound isolation and standardization of such components in addition to new compositions for therapeutic use. Pharmaceutical companies such as Ranbaxy, Lupin and Panacea Biotec are increasingly patenting on herbal drugs. There is increased patenting activity related to diabetes, cancer, cardiovascular diseases, asthma and arthritis in India and abroad. 相似文献997.
Almeida IF Martins HM Santos SM Freitas MS da Costa JM D Almeida Bernardo FM 《Toxins》2011,3(3):163-171
Thesafety characteristics of feed used in fish and crustacean aquaculture systems are an essential tool to assure the productivity of those animal exploitations. Safety of feed may be affected by different hazards, including biological and chemical groups. The aim of this preliminary study was to evaluate fungi contamination and the presence of aflatoxins in 87 samples of feed for sea bass, collected in Portugal. Molds were found in 35 samples (40.2%) in levels ranging from 1 to 3.3 log10 CFU∙g−1. Six genera of molds were found. Aspergillus flavus was the most frequent, found in all positive samples, with a range from 2 to 3.2 log10 CFU∙g−1. Aspergillus niger was found in 34 samples (39.1%), ranging from 1 to 2.7 log10 CFU∙g−1. Aspergillus glaucus was found in 26 samples (29.9%) with levels between 1 and 2.4 log10 CFU∙g−1. Penicillium spp. and Cladosporium spp. were both found in 25 samples (28.7%). Fusarium spp. was found in 22 samples (25.3%), ranging from 1 to 2.3 log10 CFU∙g−1. All feed samples were screened for aflatoxins using a HPLC technique, with a detection limit of 1.0 μg∙kg−1. All samples were aflatoxin negative. 相似文献
998.
J White 《The Australasian medical journal》2011,4(12):814-819
There is good evidence that regular fish consumption can lead to a range of health benefits, and that there is high public awareness of this fact. In spite of this, Australians do not, on average, consume fish to recommended levels. An intervention is proposed, leveraging social media and mobile technology. This approach is justified on the basis of a precedence of similar initiatives and the calculation of a potential target group size of 2.8 million adult Australians. 相似文献
999.
Francesco Caponio Carmine Summo Antonella Pasqualone Tommaso Gomes 《Journal of food composition and analysis》2011,24(8):1117-1122
An experimental investigation was carried out to assess the fatty acid composition and the degradation level of the covering oil present in canned fish. The most commonly marketed canned fish types were considered (tuna, sardines, anchovies, mackerels), as well as different kinds of covering oil: extra virgin olive oil, olive oil, refined seed oil. A total of 68 samples were analyzed. Two-way analysis of variance, followed by Fisher's Least Significant Difference test for multiple comparisons, and principal component analysis were carried out to compare the effect of both type of oil used and kind of fish on oil quality. The obtained results showed the lowest extent of both hydrolytic and oxidative degradation in samples containing extra virgin olive oil. In particular, the contents of triacylglycerol oligopolymers, imputable to secondary oxidative degradation, were equal to 0.17%, 0.50% and 0.74% for extra virgin olive oil, olive oil and refined seed oil, respectively. Olive oil showed significantly higher hydrolytic degradation, with diacylglycerols equal to 3.37%, but lower oxidative degradation and trans isomers content than refined seed oil. Finally, the type of fish did not seem to influence the extent of oxidative and hydrolytic degradation, with the only exception of sardines’ covering oil. This oil, characterized by the highest polyunsaturated fatty acid content, showed the highest values of oxidized triacylglycerols (1.32%) and specific absorption at 232 (K232, 4.030), indices of primary oxidative degradation. 相似文献
1000.
河豚鱼肝油中EPA、DHA的纯化与含量测定 总被引:1,自引:0,他引:1
目的:研究河豚鱼肝油中二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)的纯化方法,并建立EPA和DHA的含量测定方法。方法:河豚鱼肝油经精炼、盐析、低温-钾盐乙醇法和尿素包合法相结合纯化得不饱和脂肪酸;不饱和脂肪酸经甲脂化后,采用气相色谱法测定EPA和DHA的含量。结果:河豚鱼肝油经纯化可获得高纯度的不饱和脂肪酸;EPA和DHA的含量分别为0.2619g·g-1和0.4527g·g-1。EPA甲酯和DHA甲酯标准品浓度均在0.05~0.25mg·mL-1范围内同其与内标的峰面积比值呈良好的线性关系(r分别为0.9997、0.9998)。结论:河豚鱼肝油中EPA和DHA的纯化方法可行;检测方法操作简单、结果准确、重复性良好,是一种可行的含量测定方法。 相似文献