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Feijoa sellowiana Berg. fruits and especially the acetonic extract have been shown to possess biological activities, although the responsible compounds have never been identified. The present study was designed to evaluate the anti-inflammatory activity of an acetonic extract from F. sellowiana Berg. fruits on the nitric oxide (NO) pathway, which plays an important role in inflammation. To this aim the J774 cell line, which expresses inducible nitric oxide synthase (iNOS) following stimulation with lipopolysaccharide (LPS), has been utilized, and the effects of this extract and its fractions on NO production, iNOS protein expression, and signal pathways involved in its regulation have been evaluated. This study demonstrates that at least some part of the anti-inflammatory activity of the acetonic extract is due to the suppression of NO production by flavone and stearic acid. The mechanism of this inhibition seems to be related to an action on the expression of the enzyme iNOS through the attenuation of nuclear factor kappaB (NF-kappaB) and/or mitogen-activated protein kinase (MAPK) activation.  相似文献   
3.
The objective of this study was to evaluate the effect of reduced-calorie avocado paste on lipid serum profile, insulin sensitivity, and hepatic steatosis in rats fed a hypercholesterolemic-high fructose diet. Thirty five male Wistar rats were randomly separated in five groups: Control group (ground commercial diet); hypercholesterolemic diet plus 60 % fructose solution (HHF group); hypercholesterolemic diet plus 60 % fructose solution supplemented with avocado pulp (HHF+A group); hypercholesterolemic diet plus 60 % fructose solution supplemented with reduced-calorie avocado paste (HHF+P group); and hypercholesterolemic diet plus 60 % fructose solution supplemented with a reduced-calorie avocado paste plus fiber (HHF+FP group). The A, P, and FP were supplemented at 2 g/kg/d. The study was carried out for seven weeks. Rats belonging to the HHF group exhibited significantly (P?≤?0.05) higher total cholesterol, triglycerides, and insulin levels in serum as well as lower insulin sensitivity than the control group. Supplementation with reduced-calorie avocado paste showed a significant (P?≤?0.05) decrease in total cholesterol (43.1 %), low-density lipoprotein (45.4 %), and triglycerides (32.8 %) in plasma as well as elevated insulin sensitivity compared to the HHF group. Additionally, the liver enzymes alanine aminotransferase and aspartate aminotransferase decreased significantly in the HHF-P group (39.8 and 35.1 %, respectively). These results are likely due to biocompounds present in the reduced-calorie avocado paste, such as polyphenols, carotenoids, chlorophylls, and dietary fibre, which are capable of reducing oxidative stress. Therefore, reduced-calorie avocado paste attenuates the effects of a hypercholesterolemic-high fructose diet in rats.  相似文献   
4.
The Δ6 and Δ5 desaturases and elongases show only very limited activity in marine fish, and little is known of the possibility of enhancing Δ6 desaturase gene expression in these fish. The use of plant oils in marine fish diets is limited by their lack of n−3 highly unsaturated fatty acids (HUFA) despite an abundant content of the 18C fatty acid precursor linoleic and α-linolenic acids. The objective of the present study was to determine the ability of larval gilthead seabream to utilize vegetable oils and assess the nutritional regulation of Δ6 desaturase gene expression. Seventeen-day-old gilthead seabream larvae were fed during a 17-day period with one of four different microdiets formulated with either sardine fish oil (FO), soybean, rapeseed or linseed oils, respectively, or a fifth diet containing defatted squid meal and linseed oil. Good larval survival and growth, both in terms of total length and body weight, were obtained by feeding the larvae either rapeseed, soybean or linseed oils. The presence of vegetable oils in the diet increased the levels of 20:2n−9 and 20:2n−6, 18:2n−9, 18:3n−6, 20:3n−6 and 20:4n−6, in larvae fed rapeseed and soybean oils in comparison to those fed FO. In addition, a sixfold increase in the relative expression of Δ6 desaturase-like gene was found in larvae fed rapeseed and soybean oils, denoting the nutritional regulation of desaturase activity through its gene expression in this fish species. However, feeding linseed oil did not increase the expression of the Δ6 desaturase gene to such a high extent.  相似文献   
5.
The dimethylformamide extracts from sewage sludges from a chosen sewage — treatment plant in highly industrialized region of Poland were investigated. Using the column chromatography with Al2O3 and silicic acid as the stationary phases, the fraction of azaarenes has been separated. GC-MS analysis of azaarenes fraction made it possible to identify 10 azaarenes and several of their alkyl derivatives, which dominate in the organic matter extracted from sewage sludges. The silicic acid column chromatography in connection with the reduction of nitroarenes and derivatization with pentafluoropropionic acid anhydride yielded an enriched nitrofraction. Nitroarenes present in this fraction as amide derivatives were also analysed by GGMS method. There was found presence of 3 nitroarenes and their methyl derivatives.  相似文献   
6.
Bahia grass (Paspalum notatum), johnson grass (Sorghum halpense) and switchgrass (Panicum virginatum) werecompared for their ability to accumulate 137Csand 90Sr from three different contaminated soilsin the presence and absence of either sphagnum peator poultry litter amendments. Above-ground plantbiomass did not differ between plants that were notexposed to these radionuclides and those that wereexposed to soil containing 137Cs or 90Sr.After three harvests, bahia, johnson and switchgrassplants accumulated from 17.2 to 67.3% of the137Cs and from 25.1 to 61.7% of the 90Sradded to the soil. Poultry litter and peat mossamendments increased aboveground plant biomass,activity of 137Cs or 90Sr in plant tissue, %accumulation of 137Cs or 90Sr from soil andthe plant bioconcentration ratio at each harvestcompared to the control (no amendment) treatment. Thegreatest increases in plant biomass, and radionuclideaccumulation were observed with poultry litter foreach of the three grass species. Johnson grass hadgreater aboveground plant biomass, activity of137Cs and 90Sr in plant tissue, %accumulation of 137Cs or 90Sr from soil andbioconcentration ratio in each soil amendment, at eachharvest compared to bahia and switchgrass. Thegreatest accumulation of 137Cs and 90Sr wasmeasured in johnson grass grown in soil that wasamended with poultry litter. These results suggestthat plant species selection and agronomic practicesmay need to be considered to maximize phytoremediationof radionuclide contaminated soils.  相似文献   
7.
Erythromycin is an antimicrobial agent recommended for the control and treatment of diseases caused by gram-positive bacteria. Few studies, however, have determined the metabolic and pharmacokinetic aspects of this antimicrobial agent in fish. The aim of the present study, therefore, was to determine the accumulation and depletion time of erythromycin after administration of medicated feed containing 52 mg kg(-1) body weight day(-1) for 8 days in rainbow trout (Oncorhynchus mykiss). Results were analyzed following the European Agency for Evaluation of Medicinal Products guidelines. We measured a withdrawal time of 187°C-day (°C-day=water temperature×days), lower than the value (500°C-day) recommended by Council Directive 2004/28/EC for veterinary medicinal products. Our results provide data to establish therapeutic regimens for the use of erythromycin in aquaculture.  相似文献   
8.
Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.  相似文献   
9.
We developed a TaqMan real-time polymerase chain reaction (PCR) assay for the quantitative detection of Theileria equi from the in vitro-cultured parasite and field blood samples collected from horses living in Ghana and Brazil. The detection limit for the assay was determined to be 1.5 parasites/microl per sample, and the quantitative capacity was demonstrated using the in vitro-cultured parasite. For field applications, the real-time PCR assay was compared to a previously established nested PCR assay used as the gold standard for the real-time PCR assay. Of 65 field blood samples, 46 samples were T. equi-positive in the nested PCR assay, while the real-time PCR assay also detected the parasite in all 46 of the nested PCR-positive samples but did not detect T. equi in the remaining 19 negative blood samples. This quantitative real-time PCR assay provides a valuable tool for fast laboratory diagnostic assessment of T. equi infection in horses.  相似文献   
10.
River crab (RC) meal (Procambarus clarkii) and marine crab (MC) meal (Chaceon affinis) were tested as a partial replacement for fish meal in diets for red porgy (Pagrus pagrus), and their effects on growth performance, fish proximate composition and skin colouration were evaluated. Red porgy were fed during 165 days with five diets. High‐quality fish meal diet was used as a control diet (CD). Protein of fish meal in the control was replaced by increasing the dietary levels of protein derived from RC and MC by up to 10% and 20% of each of them (RC10, RC20, MC10 and MC20). Fish fed on MC20 showed the highest values in feed intake, weight gain and growth (%). No differences were found in FCR and protein efficiency ratio among the treatments. Inclusion of both crab meals in diets significantly decreased the lipid content in whole fish compared with the control animals. On the other hand, no differences in muscle composition were found between the diets. Feeding both crab meals resulted in colour improvement compared with that of the control fish, with better hue values for the RC meal group than those for the MC meal group. The crab meals tested in the present study are suitable as a partial replacement for fish meal in diets for the red porgy, with the MC meal improving growth and both crabs meals improving skin colour, with further improvements in skin colour produced in fish‐fed diets containing the RC meal.  相似文献   
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