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61.
1H‐NMR analysis of the hepatopancreas, muscle and haemolymph of Astacus leptodactylus after feeding with polyphenol‐enriched diet is reported. 1H‐NMR spectra of lipophilic extracts showed the presence of cholesterol, fatty acid residues, phospholipids and triglycerides. 1H‐NMR spectra of aqueous extracts identified 35 metabolites in the hepatopancreas, 31 in the muscle and 22 in the haemolymph. A total of 20 metabolites (amino acids and their derivatives) were present in the hepatopancreas, the muscle and the haemolymph. A total of 10 metabolites were present in both the hepatopancreas and the muscle (five amino acids, 2‐hydroxybutyrate, choline, myo‐inositol, glycogen and uracil). 2‐Hydroxyisobutyrate and creatine were present in both the hepatopancreas and the haemolymph. Phosphorylethanolamine, phosphocholine and fumarate were present only in the hepatopancreas and isoleucine only in the muscle. Statistical analysis showed that the percentage of weight gain was statistically higher in polyphenol‐enriched diet groups compared to the control and that polyphenols had a stimulating effect on the general metabolism. No stress‐related metabolites were higher in crayfish fed with polyphenol‐enriched diet. Conversely, phosphatidylcholine, cholesterol and DHA, linked to resistance to environmental stress and diseases, were higher compared to the control diet. This study indicates that 1H‐NMR is a useful tool to study the metabolomics in relation to diet differences.  相似文献   
62.
This study aimed to evaluate the exogenous progesterone (P4) effect on the luteal function from Day 16 to Day 21 of the oestrous cycle in inseminated goats with unknown pregnancy status. A total of 54 does passed through a short progestin-based synchronization protocol and, on Day 16 of the following oestrous cycle, 27 does received a new P4 device which was retained until Day 21. Blood samples were collected daily from all does during this period, as well as on Day 24. Pregnancy diagnoses were performed on Day 30. Serum P4 values from 26 animals (GNPSP: Group of non-pregnant does with second sponge: n = 8; GNPNSP: Group of non-pregnant does without second sponge: n = 6; GPSP: Group of pregnant does with second sponge: n = 5; GPNSP: Group of pregnant does without second sponge: n = 7) were determined by radioimmunoassay commercial kits. No P4 differences were found between groups (GNPSP: 3.1 ± 2.8; 1.7 ± 1.8; 0.4 ± 1.0; and 0.0 ± 0.0 vs. GNPNSP: 4.4 ± 1.8; 3.0 ± 2.2; 0.8 ± 0.8; and 0.0 ± 0.0 or GPSP: 4.2 ± 1.0; 3.4 ± 0.6; 3.3 ± 1.6; 3.2 ± 0.9; 3.6 ± 1.2; 3.5 ± 1.3; 2.7 ± 1.3 vs. GPNSP: 4.4 ± 1.6; 3.6 ± 1.5; 3.7 ± 1.5; 3.8 ± 1.4; 3.2 ± 1.2; 3.1 ± 1.2; 3.6 ± 1.1; D16, D17, D18, D19, D20, D21, D24, respectively) or for the interaction of group and time. In conclusion, a second progestogen device had no effect on luteolysis or early pregnancy in the following oestrous cycle.  相似文献   
63.
Variation in movement between individuals can have important ecological effects on populations and ecosystems, yet the factors driving differences in movement and their consequences remain poorly understood. Here, individual variability in the movements of juvenile (age 0 +  and 1 +  year) pike Esox lucius was assessed using passive integrated transponder (PIT) telemetry in off‐channel nursery areas over a 26‐ month period. Differences in the movement patterns of individuals were tested against their body sizes, ages, growth rates and trophic positions using data collected through a combination of catch‐and‐release sampling and stable isotope analyses. Results revealed that variation in movement between individuals was affected by age, with 1 +  individuals moving more than individuals of age 0 + , but not length. Individuals whose TP was low on their initial capture event moved significantly less than those with a higher initial TP. Individuals that moved more grew faster and achieved a higher final TP. These results suggest that higher activity (i.e., increased movement) increases resource acquisition that enhances growth rates, which could ultimately maximise individual performances.  相似文献   
64.
Oxidation of bovine serum albumin, casein, and lactalbumin and the effect of different procyanidins, anthocyanins, and their aglycons (10 and 20 microM) on lactalbumin oxidation were investigated in a liposome system. Samples were incubated in the dark at 37 degrees C with copper, and the extent of oxidation was measured by determining the loss of tryptophan fluorescence and the formation of protein carbonyls, conjugated diene hydroperoxides, and hexanal. The correlation between different protein and lipid oxidation measurements was good and statistically significant. Casein was the most stable protein in the liposome model, and it was also the best inhibitor of liposome oxidation. All tested anthocyanins and other phenolic compounds inhibited both lipid and protein oxidation. There were no systematic differences with anthocyanins and their aglycons in relation to the concentrations used or glycosylation with either glucose or rutinose. Procyanidins B1 and B2 and ellagic acid were potentially better antioxidants than anthocyanins due to their several hydroxyl groups as measured by both protein and lipid oxidation. In conclusion, oxidative deterioration of liposomes due to protein-lipid interaction is inhibited by anthocyanins, procyanidins, and ellagitannin present, for example, in berries.  相似文献   
65.
To clarify whether a particular group of soils of Archangelsk region (European N Russia) with humus‐rich topsoils exceeding the plowing zone supports an anthropogenic formation, four exemplary profiles were investigated. The investigation sites are characterized by distinct elevated surfaces, and the soils show thick toplayers of up to 60 cm with enrichment of soil organic matter and artifacts like brick, charcoal, and peat fragments, all indicating an anthropogenic origin. Increased phytolith amounts and high P contents of up to 800 mg kg–1 citric acid–soluble P and up to 1,400 mg kg–1 total P in the top horizons support an anthropogenic influence. These properties are very similar to the Plagganthrepts of NW Europe. The same is true regarding the main management aims: increasing soil fertility and overcoming the need of bedding materials. Having the required depths of the anthropogenic topsoil, the properties of the soils of the Archangelsk region allow a classification as Agrozems (Russian classification), Plaggenesche (German classification), and Plagganthrepts (US taxonomy). Since the high base saturation of the topsoil excludes a designation as plaggic horizon, the topsoil has to be considered as terric horizon, which leads to a classification as Terric Anthrosol according to WRB.  相似文献   
66.
Fat type in diet is responsible for specific changes in gut microbiota (GM). Extra virgin olive oil (EVOO) has been shown to be beneficial for blood pressure and to produce effects on GM. To analyze the cause-effect relationship between intestinal microbial changes and blood pressure, we studied the effect of EVOO on fecal microbiota and systolic blood pressure (SBP) levels in spontaneously hypertensive rats (SHR). SHR were fed either an enriched EVOO diet or a standard diet for a period of 12 weeks. At the end of the experimental period, the microbial profiles in the feces were studied in both groups by using PCR-denaturing gradient gel electrophoresis. Real-time PCR was used to quantify the selected bacterial groups. The results demonstrated significant differences when using Lactobacillus (p<0.05), clostridia XIV (p<0.01) and universal (p<0.05) primers. A significant (r=?0.475; p=0.04) inverse correlation between the abundance of clostridia XIV and SBP, which depends on the type of diet, was also observed. Finally, the results suggested an increase in the microbial diversity of the feces of the animals fed the EVOO diet. These results strongly connect the pattern of GM in SHR fed a diet enriched with EVOO to the lower levels of SBP observed in these animals at the end of the feeding period.  相似文献   
67.
68.
Haemophilus parasuis is a colonizer of the upper respiratory tract of healthy pigs, but virulent strains can cause a systemic infection characterized by fibrinous polyserositis, commonly known as Glässer’s disease. The variability in virulence that is observed among H. parasuis strains is not completely understood, since the virulence mechanisms of H. parasuis are largely unknown. In the course of infection, H. parasuis has to survive the host pulmonary defences, which include alveolar macrophages, to produce disease. Using strains from different clinical backgrounds, we were able to detect clear differences in susceptibility to phagocytosis. Strains isolated from the nose of healthy animals were efficiently phagocytosed by porcine alveolar macrophages (PAM), while strains isolated from systemic lesions were resistant to this interaction. Phagocytosis of susceptible strains proceeded through mechanisms independent of a specific receptor, which involved actin filaments and microtubules. In all the systemic strains tested in this study, we observed a distinct capsule after interaction with PAM, indicating a role of this surface structure in phagocytosis resistance. However, additional mechanisms of resistance to phagocytosis should be explored, since we detected different effects of microtubule inhibition among systemic strains.  相似文献   
69.
The mechanical properties and responses of cells to external stimuli (including drugs) are closely connected to important phenomena such as cell spreading, motility, activity, and potentially even differentiation. Here, reversible changes in the viscoelastic properties of surface-attached fibroblasts were induced by the cytoskeleton-perturbing agent cytochalasin D, and studied in real-time by the quartz crystal microbalance with dissipation (QCM-D) technique. QCM-D is a surface sensitive technique that measures changes in (dynamically coupled) mass and viscoelastic properties close to the sensor surface, within a distance into the cell that is usually only a fraction of its size. In this work, QCM-D was combined with light microscopy to study in situ cell attachment and spreading. Overtone-dependent changes of the QCM-D responses (frequency and dissipation shifts) were first recorded, as fibroblast cells attached to protein-coated sensors in a window equipped flow module. Then, as the cell layer had stabilised, morphological changes were induced in the cells by injecting cytochalasin D. This caused changes in the QCM-D signals that were reversible in the sense that they disappeared upon removal of cytochalasin D. These results are compared to other cell QCM-D studies. Our results stress the combination of QCM-D and light microscopy to help interpret QCM-D results obtained in cell assays and thus suggests a direction to develop the QCM-D technique as an even more useful tool for real-time cell studies.  相似文献   
70.
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