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941.
Nanoemulsion from essential oil of Pterodon emarginatus (Fabaceae) shows in vitro efficacy against monogeneans of Colossoma macropomum (Pisces: Serrasalmidae) 下载免费PDF全文
D S S Valentim J L Duarte A E M F M Oliveira R A S Cruz J C T Carvalho E C Conceição C P Fernandes M Tavares‐Dias 《Journal of fish diseases》2018,41(3):443-449
Outbreaks of diseases pose a major threat to sustainable aquaculture development worldwide. Application of herbal products to combat parasitic diseases provides an alternative approach for sustainable aquaculture. This study investigated the in vitro antiparasitic effects of an oil‐in‐water nanoemulsion prepared using the essential oil from Pterodon emarginatus, against monogeneans infesting Colossoma macropomum. Gill arches from C. macropomum (47.6 ± 14.5 g and 13.5 ± 1.4 cm) that were naturally parasitized by Anacanthorus spathulatus, Notozothecium janauachensis and Mymarothecium boegeri were immersed in different dispersions of the P. emarginatus nanoemulsions (0, 50, 100, 200, 400 and 600 mg/L). The major compounds presented in the essential oil of P. emarginatus were β‐elemene, β‐caryophyllene and α‐humulene. Characterization of these nanoemulsions showed that they have a small mean droplet size and low polydispersity index, which is concordant with stable systems. In this in vitro trial, the P. emarginatus nanoemulsion concentrations of 100, 200, 400 and 600 mg/L presented 100% helminthic efficacy against monogeneans of the gills of C. macropomum. The highest two concentrations used (400 and 600 mg/L) were seen to immobilize the parasites after only 15 min. Therefore, it would be worthwhile testing these concentrations in therapeutic baths against monogeneans of C. macropomum. 相似文献
942.
Crystalline abscisin II, with a tentative molecular formula of C(15)H(20)O(4), has been isolated from young cotton fruit. It accelerates abscission when applied in amounts as low as 0.01 microg per abscission zone. It inhibits indoleacetic acid-induced straight growth of Avena coleoptiles but has no gibberellin activity on dwarf maize. 相似文献
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944.
A potential second messenger role for unsaturated fatty acids: activation of Ca2+-dependent protein kinase 总被引:39,自引:0,他引:39
Arachidonate and other unsaturated long-chain fatty acids were found to activate protein kinase C from human neutrophils. Kinase activation by arachidonate required calcium and was enhanced by diolein but did not require exogenous phosphatidylserine. Submaximal levels of arachidonate also enhanced the affinity of the kinase for calcium during activation by phosphatidylserine. Thus the release of arachidonate, which is triggered in many cell types by ligand-receptor interactions, could play a second messenger role in the regulation of cellular function by activation of protein kinase C. 相似文献
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La Ragione RM Best A Aktan I Clifton-Hadley FA Dugdale AH Weyer U Crawley T Townsend P Cooley WA Johnson L Wangoo A Woodward MJ Wales AD 《Research in veterinary science》2012,93(1):42-45
Escherichia coli O115 has been isolated from healthy sheep and was shown to be associated with attaching-effacing (AE) lesions in the large intestine. Following previous observations of interactions between E. coli O157 and O26, the aim of the present study was to assess what influence an O115 AE E. coli (AEEC) would have on E. coli O157 colonisation in vitro and in vivo. We report that E. coli O115- and O157-associated AE lesions were observed on HEp-2 cells and on the mucosa of ligated ovine spiral colon. In single strain inoculum, E. coli O115 associated intimately with HEp-2 cells and the spiral colon in greater numbers than E. coli O157:H7. However, in mixed inoculum studies, the number of E. coli O115 AE lesions was significantly reduced suggesting negative interference by E. coli O157. Use of the ligated colon model in the present work has allowed in vitro observations to be extended and confirmed whilst using a minimum of experimental animals. The findings support a hypothesis that some AEEC can inhibit adhesion of other AEEC in vivo. The mechanisms involved may prove to be of utility in the control of AE pathovars. 相似文献
948.
D F Barker S L Hostikka J Zhou L T Chow A R Oliphant S C Gerken M C Gregory M H Skolnick C L Atkin K Tryggvason 《Science (New York, N.Y.)》1990,248(4960):1224-1227
X-linked Alport syndrome is a hereditary glomerulonephritis in which progressive loss of kidney function is often accompanied by progressive loss of hearing. Ultrastructural defects in glomerular basement membranes (GBM) of Alport syndrome patients implicate an altered structural protein as the cause of nephritis. The product of COL4A5, the alpha 5(IV) collagen chain, is a specific component of GBM within the kidney, and the gene maps to the same X chromosomal region as does Alport syndrome. Three structural aberrations were found in COL4A5, in intragenic deletion, a Pst I site variant, and an uncharacterized abnormality, which appear to cause nephritis and deafness, with allele-specific severity, in three Alport syndrome kindreds in Utah. 相似文献
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