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41.
Siddhartha S. Saha Pritha Dasgupta Sumita Sengupta Mahua Ghosh 《Biochimica et Biophysica Acta (BBA)/General Subjects》2012
Background
α-Eleostearic acid and punicic acid, two typical conjugated linolenic acid (CLnA) isomers present in bitter gourd and snake gourd oil respectively, exhibit contrasting cis-trans configuration which made them biologically important.Methods
Rats were divided into six groups. Group 1 was control and group 2 was treated control. Rats in the groups 3 and 4 were treated with mixture of α-eleostearic acid and punicic acid (1:1) (0.5% and 1.0% respectively) while rats in the groups 5 and 6 were treated with 0.5% of α-eleostearic acid and 0.5% of punicic acid respectively along with sodium arsenite by oral gavage once per day.Results
Results showed that increase in nitric oxide synthase (NOS) activity, inflammatory markers expression, platelet aggregation, lipid peroxidation, protein oxidation, DNA damage and altered expression of liver X receptor-α (LXR-α) after arsenite treatment were restored with the supplementation of oils containing CLnA isomers. Altered activities of different antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and ferric reducing ability of plasma (FRAP) also restored after oil supplementation. Altered morphology and fluidity of erythrocyte membrane studied by atomic force and scanning electron microscopy, after stress induction were significantly improved due to amelioration in cholesterol/phospholipid ratio and fatty acid profile of membrane. Oils treatment also improved morphology of liver and fatty acid composition of hepatic lipid.Conclusions
Overall two isomers showed synergistic antioxidant and anti-inflammatory effect against induced perturbations and membrane disintegrity.General significance
Synergistic antioxidant and anti-inflammatory role of these CLnA isomers were established by this study. 相似文献42.
Angela Schwarm Monika Schweigel-Röntgen Michael Kreuzer Sylvia Ortmann Fiona Gill Björn Kuhla 《Archives of animal nutrition》2015,69(3):159-176
The aim of the present experiment was to compare silage prepared from maize having a brown midrib (BMR) mutation with control (CTR) maize to identify their effects on enteric methane emission, digesta mean retention time (MRT), ruminal fermentation and digestibility. In addition, the utility of archaeol present in faecal samples was validated as a proxy for methane production. Seven German Holstein heifers were fed total mixed rations with a maize-silage proportion (either BMR or CTR) of 920 g/kg dry matter (DM) in a change-over design. Heifers were fed boluses with markers to measure MRT; faeces were collected for 7 days and rumen fluid was collected on the penultimate day. Methane emission was measured in respiration chambers on one day. Data were analysed by t-test and regression analysis. DM intake did not differ between the two diets. The apparent digestibility of DM and most nutrients was unaffected by diet type, but apparent digestibility of neutral and acid detergent-fibre was higher in those heifers fed BMR than in those fed CTR. Comparisons between diets revealed no difference in particle or solute MRT in the gastro-intestinal tract and the reticulorumen. Concentrations of short-chain fatty acid and ammonia in rumen fluid and its pH were not affected by silage type. Independent of the mode of expression [l/d, l/kg DM intake, l/kg digested organic matter], methane emissions were not affected by maize-silage type, but with BMR, there was a trend towards lower methane production per unit of digested neutral detergent fibre than there was with CTR silage. Results of the present study show that feeding heifers BMR silage does not increase methane emissions despite a higher fibre digestibility as compared to CTR silage. Therefore, it is assumed that improvements in animal productivity achieved by feeding BMR silage, as some studies have reported, can be obtained without extra environmental cost per unit of milk or meat. Neither faecal archaeol content [µg/g] nor daily amount excreted [mg/d] is suitable to predict methane production in absolute terms [l per day]. However, faecal archaeol content has a certain potential for predicting the methane yield [l per kg DM intake] of individual animals. 相似文献
43.
Molecular dynamic simulations of systems of single-walled carbon nanotubes (CNTs) in liquid crystalline solvents were performed, in order to investigate the effect of the molecular structure and phase of the liquid crystal (LC) on the interactions between the CNTs. Three different LC molecules (5CB, 8CB and 5CF) were considered in our study. Our results with 5CB and 8CB suggest that increasing the chain length of the hydrophobic part of the LC molecule by three carbon atoms is insufficient to decrease the tendency for the CNTs to aggregate in the LCs. Additionally, varying the phase of the LC is also insufficient to decrease the aggregation tendency of the CNTs. However, simulations with 5CF (which has fluorine atoms in the head group of the LC molecule) suggest that this LC solvent can decrease the tendency of the CNTs to aggregate. This study is relevant to assist experimentalists with the development of high-quality dispersions of large concentrations of CNTs in the LCs. 相似文献
44.
以小鼠的肝、肺组织的正常细胞与肝肿瘤细胞(Hepa1-6)、肺肿瘤细胞(LLC)为研究对象,通过CTFM(cell traction force microscopy)法测定了4组细胞系的牵引力;用荧光抗体染色技术比较了小鼠细胞的α-SMA蛋白在癌变前后的变化。实验发现:与小鼠正常细胞相比,在α-SMA的表达水平上,Hepa1-6细胞α-SMA的平均光密度减小了47.9%,LLC细胞下降了52.3%;而Hepa1-6细胞牵引力的均方根值减小了53.4%,LLC细胞减小了49.7%。这说明α-SMA的表达与牵引力的变化以及细胞癌变的过程是密切相关的。 相似文献
45.
Nicholas Ali Michael Skipper Andersen John Rasmussen D. Gordon E. Robertson Gholamreza Rouhi 《Computer methods in biomechanics and biomedical engineering》2014,17(14):1602-1616
The central tenet of this study was to develop, validate and apply various individualised 3D musculoskeletal models of the human body for application to single-leg landings over increasing vertical heights and horizontal distances. While contributing to an understanding of whether gender differences explain the higher rate of non-contact anterior cruciate ligament (ACL) injuries among females, this study also correlated various musculoskeletal variables significantly impacted by gender, height and/or distance and their interactions with two ACL injury-risk predictor variables; peak vertical ground reaction force (VGRF) and peak proximal tibia anterior shear force (PTASF). Kinematic, kinetic and electromyography data of three male and three female subjects were measured. Results revealed no significant gender differences in the musculoskeletal variables tested except peak VGRF (p = 0.039) and hip axial compressive force (p = 0.032). The quadriceps and the gastrocnemius muscle forces had significant correlations with peak PTASF (r = 0.85, p < 0.05 and r = ? 0.88, p < 0.05, respectively). Furthermore, hamstring muscle force was significantly correlated with peak VGRF (r = ? 0.90, p < 0.05). The ankle flexion angle was significantly correlated with peak PTASF (r = ? 0.82, p < 0.05). Our findings indicate that compared to males, females did not exhibit significantly different muscle forces, or ankle, knee and hip flexion angles during single-leg landings that would explain the gender bias in non-contact ACL injury rate. Our results also suggest that higher quadriceps muscle force increases the risk, while higher hamstring and gastrocnemius muscle forces as well as ankle flexion angle reduce the risk of non-contact ACL injury. 相似文献
46.
Concomitant activation of the PI3K/Akt and ERK1/2 signalling is involved in cyclic compressive force‐induced IL‐6 secretion in MLO‐Y4 cells 下载免费PDF全文
47.
In the present investigation, steady‐state and time‐resolved fluorescence with the combination of circular dichroism (CD) spectroscopic techniques were applied to study the interactions of the well‐known dye rhodamine 6 G (R6G) with the haem protein human myoglobin (Mb). From the analysis of the results it appears that the static type of fluorescence quenching mechanism is primarily involved, due to ground‐state interactions. Although considerable overlapping of fluorescence emission of the dye R6G with the absorption of Mb in the Q‐band region exists, the possibility of occurrences of the excitational singlet–singlet non‐radiative energy transfer process from R6G to Mb appears to be unlikely, according to time‐resolved fluorescence measurements. From the determinations of the thermodynamic parameters, it was apparent that the combined effect of van der Waals' interactions and hydrogen bonding plays a vital role in Mb–R6G interactions. Induced circular dichroism (ICD) studies demonstrate the possibility of interactions between R6G and Mb. The binding constants, number of binding sites and thermodynamic parameters have been computed. From CD measurements it is apparent that the binding of the dye R6G with the haem protein Mb induces negligible conformational changes in the protein and Mb retains its secondary structure and helicity when it interacts with R6G. The present detailed studies on the interactions with Mb should be helpful in further advancement of medical diagnostics and biotechnology. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
48.
Community survey of ammonia-oxidizing bacteria in full-scale activated sludge processes with different solids retention time 总被引:7,自引:0,他引:7
Hallin S Lydmark P Kokalj S Hermansson M Sörensson F Jarvis A Lindgren PE 《Journal of applied microbiology》2005,99(3):629-640
AIMS: To study the effects of different solids retention time (SRT) on the nitrification activity and community composition of ammonia-oxidizing bacteria (AOB) in two full-scale activated sludge processes during a 5-month period. METHODS AND RESULTS: The AOB community composition was analysed using fluorescence in situ hybridization (FISH) and denaturing gradient gel electrophoresis (DGGE), and the identified populations were enumerated by quantitative FISH. Potential nitrification rates were determined in batch tests and the in situ rates were calculated from mass balances of nitrogen in the plants. Increased SRT reduced the nitrification activity, but neither the number per mixed liquor suspended solids nor community composition of AOB were affected. Two dominant AOB populations related to Nitrosomonas europaea and Nitrosomonas oligotropha were identified by FISH, whereas only the latter could be detected by DGGE. CONCLUSIONS: The effect of a longer SRT on the activity was probably because of physiological changes in the AOB community rather than a change in community composition. SIGNIFICANCE AND IMPACT OF THE STUDY: Physiological alterations of a stable AOB community are possible and may stabilize activated sludge processes. The commonly used FISH probes designed to target all beta-proteobacterial AOB does not detect certain Nitrosomonas oligotropha populations, leading to an underestimation of AOB if a wider set of probes is not used. 相似文献
49.
Natalello A Prokorov VV Tagliavini F Morbin M Forloni G Beeg M Manzoni C Colombo L Gobbi M Salmona M Doglia SM 《Journal of molecular biology》2008,381(5):1349-1361
The existence of several prion strains and their capacity of overcoming species barriers seem to point to a high conformational adaptability of the prion protein. To investigate this structural plasticity, we studied here the aggregation pathways of the human prion peptide PrP82-146, a major component of the Gerstmann-Sträussler-Scheinker amyloid disease.By Fourier transform infrared (FT-IR) spectroscopy, electron microscopy, and atomic force microscopy (AFM), we monitored the time course of PrP82-146 fibril formation. After incubation at 37 °C, the unfolded peptide was found to aggregate into oligomers characterized by intermolecular β-sheet infrared bands. At a critical oligomer concentration, the emergence of a new FT-IR band allowed to detect fibril formation. A different intermolecular β-sheet interaction of the peptides in oligomers and in fibrils is, therefore, detected by FT-IR spectroscopy, which, in addition, suggests a parallel orientation of the cross β-sheet structures of PrP82-146 fibrils. By AFM, a wide distribution of PrP82-146 oligomer volumes—the smallest ones containing from 5 to 30 peptides—was observed. Interestingly, the statistical analysis of AFM data enabled us to detect a quantization in the oligomer height values differing by steps of ∼ 0.5 nm that could reflect an orientation of oligomer β-strands parallel with the sample surface. Different morphologies were also detected for fibrils that displayed high heterogeneity in their twisting periodicity and a complex hierarchical assembly.Thermal aggregation of PrP82-146 was also investigated by FT-IR spectroscopy, which indicated for these aggregates an intermolecular β-sheet interaction different from that observed for oligomers and fibrils. Unexpectedly, random aggregates, induced by solvent evaporation, were found to display a significant α-helical structure as well as several β-sheet components.All these results clearly point to a high plasticity of the PrP82-146 peptide, which was found to be capable of undergoing several aggregation pathways, with end products displaying different secondary structures and intermolecular interactions. 相似文献