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161.
162.
El Hafidi M Pérez I Zamora J Soto V Carvajal-Sandoval G Baños G 《American journal of physiology. Regulatory, integrative and comparative physiology》2004,287(6):R1387-R1393
The study investigated the mechanism by which glycine protects against increased circulating nonesterified fatty acids (NEFA), fat cell size, intra-abdominal fat accumulation, and blood pressure (BP) induced in male Wistar rats by sucrose ingestion. The addition of 1% glycine to the drinking water containing 30% sucrose, for 4 wk, markedly reduced high BP in sucrose-fed rats (SFR) (122.3 +/- 5.6 vs. 147.6 +/- 5.4 mmHg in SFR without glycine, P < 0.001). Decreases in plasma triglyceride (TG) levels (0.9 +/- 0.3 vs. 1.4 +/- 0.3 mM, P < 0.001), intra-abdominal fat (6.8 +/- 2.16 vs. 14.8 +/- 4.0 g, P < 0.01), and adipose cell size were observed in SFR treated with glycine compared with SFR without treatment. Total NEFA concentration in the plasma of SFR was significantly decreased by glycine intake (0.64 +/- 0.08 vs. 1.11 +/- 0.09 mM in SFR without glycine, P < 0.001). In control animals, glycine decreased glucose, TGs, and total NEFA but without reaching significance. In SFR treated with glycine, mitochondrial respiration, as an indicator of the rate of fat oxidation, showed an increase in the state IV oxidation rate of the beta-oxidation substrates octanoic acid and palmitoyl carnitine. This suggests an enhancement of hepatic fatty acid metabolism, i.e., in their transport, activation, or beta-oxidation. These findings imply that the protection by glycine against elevated BP might be attributed to its effect in increasing fatty acid oxidation, reducing intra-abdominal fat accumulation and circulating NEFA, which have been proposed as links between obesity and hypertension. 相似文献
163.
Ashry ES Rashed N Abdel-Rahman A Awad LF Rasheed HA 《Nucleosides, nucleotides & nucleic acids》2006,25(8):925-939
Alkylation of 2-methylthiopyrimidin-4(1H)-one (1a) and its 5(6)-alkyl derivatives 1b-d as well as theophylline (7) with 2,2-bis(bromomethyl)-1,3-diacetoxypropane (2) under microwave irradiation gave the corresponding acyclonucleosides 1-[(3-acetoxy-2-acetoxymethyl-2-bromomethyl)prop-1-yl]-2-methyl-thio pyrmidin-4(1H)-ones 3a-d and 7-[(3-acetoxy-2-acetoxymethyl-2-bromomethyl)prop-1-yl]theophylline (8), which upon further irradiation gave the double-headed acyclonucleosides 1,1 '-[(2,2-diacetoxymethyl)-1,3-propylidene]-bis[(2-(methylthio)-pyrimidin-4(1H)-ones] 4a-c, and 7,7 '-[(2,2-diacetoxymethyl)-1,3-propylidene]-bis(theophylline) (9). The deacetylated derivatives were obtained by the action of sodium methoxide. The activity of deacetylated nucleosides against Hepatitis B virus was evaluated. Compound 5b showed moderate inhibition activity against HBV with mild cytotoxicity. 相似文献
164.
Aluminum mediates compositional alterations of polar lipid classes in maize seedlings 总被引:2,自引:0,他引:2
Changes in lipid composition were investigated on maize roots and shoots under aluminum stress. After 4d exposure to 100 microM Al, root growth was inhibited while shoot growth was not affected. In roots, the decrease of the DBI (double bond index) of total fatty acids may signal a decrease in membrane fluidity. The total lipids (TL) decreased by 49%, but phospholipids (PL), phosphatidylcholine (PC) and phosphatidylinositol (PI) increased to approximately 3-fold. The MGDG increased to 2-fold but no significant change was found in the DGDG. The steryl lipids (SL) increased by 69%. The SL/PL ratio decreased from 2.64 to 1.52 and the MGDG/DGDG ratio increased from 0.45 to 1.06 in roots of Al-stressed plants. Al leads to oxidative stress in roots of treated plants as indicated by the increase of malondialdehyde (MDA) concentrations. In shoots, changes in fatty acid composition were associated with an increase of the DBI in all lipid classes except that of the DGDG decreased. The PG was the lipid class which shows the large variation of fatty acid composition. No significant changes were found either for TL, PL, SL or MDA concentrations in shoots of Al-treated plants. While PE levels did not show significant change, PI and PG increased and PC decreased. However, the Al caused 87% decrease in the GL levels. The MGDG and DGDG decreased to 19- and 8-fold, respectively. The deleterious effects of Al on polar lipids could be caused by a direct intervention of Al on plasma membrane and/or alteration of cell metabolism. 相似文献
165.
Bañares VG Peterson G Aguilar D Gulayin R Sisu E Wyszynski DF Pivetta OH Tavella MJ 《Human biology; an international record of research》2005,77(2):247-256
Several studies have shown evidence of an association between the *4 allele of apolipoprotein E (APOE) and coronary heart disease (CHD) in different populations. We determined the APOE genotype and total cholesterol (TC), triglycerides (TG), and high-density lipoprotein cholesterol (HDLC) values in 189 patients with angiographically evaluated atherosclerosis. The APOE*4 allele was found to be statistically significantly more frequent (odds ratio, 1.93; 95% confidence interval, 1.12-3.32) among male patients than in a randomly chosen population-based sample. No significant difference was found when female patients were compared to the general population. The APOE*4 allele was found primarily among young (30-45-year-old) male patients (p < 0.04). Despite the ascending linear tendency of the mean TC values for genotypes APOE*2/*3, APOE*3/*3, and APOE*3/ *4 reported in our case population, no differences were observed among our patients. We conclude that the APOE*4 allele is associated with an increased risk for atherosclerotic vascular disease, that this association has an age-dependent effect, and that it acts as a genetic factor that increases susceptibility to developing the disease in young to middle-aged male adults in our population. 相似文献
166.
Cholinergic and dopaminergic neuronal differentiation of human adipose tissue derived mesenchymal stem cells 下载免费PDF全文
167.
Background
The Brain Computer Interfaces (BCI) are devices allowing direct communication between the brain of a user and a machine. This technology can be used by disabled people in order to improve their independence and maximize their capabilities such as finding an object in the environment. Such devices can be realized by the non-invasive measurement of information from the cortex by electroencephalography (EEG).Methods
Our work proposes a novel BCI system that consists of controlling a robot arm based on the user's thought. Four subjects (1 female and 3 males) aged between 20 and 29 years have participated to our experiment. They have been instructed to imagine the execution of movements of the right hand, the left hand, both right and left hands or the movement of the feet depending on the protocol established.EMOTIV EPOC headset was used to record neuronal electrical activities from the subject's scalp, these activities were then sent to the computer for analysis. Feature extraction was performed using the Principal Component Analysis (PCA) method combined with the Fast Fourier transform (FFT) spectrum within the frequency band responsible for sensorimotor rhythms (8 Hz–22 Hz).These features were then fed into a Support Vector Machine (SVM) classifier based on a Radial Base Function (RBF) whose outputs were translated into commands to control the robot arm.Results
The proposed BCI enabled the control of the robot arm in the four directions: right, left, up and down, achieving an averaged accuracy of 85.45% across all the subjects.Conclusion
The results obtained would encourage, with further developments, the use of the proposed BCI to perform more complex tasks such as execution of successive movements or stopping the execution once a searched object is detected. This would provide a useful assistance means for people with motor impairment. 相似文献168.
Histamine catabolism in Pseudomonas putida U: identification of the genes,catabolic enzymes and regulators 下载免费PDF全文
Manuel de la Torre José L. Gómez‐Botrán Elías R. Olivera Francisco Bermejo Joaquín Rodríguez‐Morán José M. Luengo 《Environmental microbiology》2018,20(5):1828-1841
In this study, the catabolic pathway required for the degradation of the biogenic amine histamine (Hin) was genetically and biochemically characterized in Pseudomonas putida U. The 11 proteins (HinABCDGHFLIJK) that participate in this pathway are encoded by genes belonging to three loci hin1, hin2 and hin3 and by the gene hinK. The enzymes HinABCD catalyze the transport and oxidative deamination of histamine to 4‐imidazoleacetic acid (ImAA). This reaction is coupled to those of other well‐known enzymatic systems (DadXAR and CoxBA‐C) that ensure both the recovery of the pyruvate required for Hin deamination and the genesis of the energy needed for Hin uptake. The proteins HinGHFLKIJ catalyze the sequential transformation of ImAA to fumaric acid via N2‐formylisoasparagine, formylaspartic acid and aspartic acid. The identified Hin pathway encompasses all the genes and proteins (transporters, energizing systems, catabolic enzymes and regulators) needed for the biological degradation of Hin. Our work was facilitated by the design and isolation of genetically engineered strains that degrade Hin or ImAA and of mutants that accumulate Ala, Asp and Hin catabolites. The implications of this research with respect to potential biotechnological applications are discussed. 相似文献
169.
Louaï Benseghir Halima Kadi‐Hanifi Nour El Islam Bachari 《African Journal of Ecology》2019,57(4):466-476
The main aim of this paper was to evaluate the use of OLI spectral data as a tool to assess the steppe vegetation in a conservation context. The field sampling was conducted for two specific areas of treatment (a) an exclosure area and (b) a free grazing area. After testing several vegetation indices (VIs), the optimal results were obtained for the Normalised Difference Vegetation Index (NDVI)‐based aboveground biomass model with r2 = 0.61 and r2 = 0.72 for total and perennial biomass, respectively. No difference between observed and predicted total and perennial biomass was found (p = 0.700 and p = 0.306, respectively). The comparison between the two treatments using the field sampling revealed a significant difference on total plant cover (p = 0.016) and total biomass (p = 0.005), with a plant cover of 50.6% and a biomass of 325.771 kg dry matter per hectare (kg DM ha?1) on average in grazed area and 66.9%, 1,407.869 kg DM ha?1 in exclosure. Finally, a concordance is noted between the results obtained by the NDVI‐based biomass model and the field sampling‐based biomass. 相似文献
170.
Diana Y. Sakae Lauriane Ramet Annabelle Henrion Odile Poirel Stphane Jamain Salah El Mestikawy Stphanie Daumas 《Genes, Brain & Behavior》2019,18(3)
The atypical vesicular glutamate transporter VGLUT3 is present in subpopulations of GABAergic interneurons in the cortex and the hippocampus, in subgroups of serotoninergic neurons in raphe nuclei, and in cholinergic interneurons in the striatum. C56BL/6N mice that no longer express VGLUT3 (VGLUT3?/?) display anxiety‐associated phenotype, increased spontaneous and cocaine‐induced locomotor activity and decreased haloperidol‐induced catalepsy. Inbred mouse strains differ markedly in their sensitivity to anxiety and behavioral responses elicited by drugs. The purpose of this study was to investigate strain differences in VGLUT3 expression levels and its potential correlates with anxiety and reward‐guided behaviors. Five inbred mouse lines were chosen according to their contrasted anxiety and drugs sensitivity: C57BL/6N, C3H/HeN, DBA/2J, 129/Sv, and BALB/c. VGLUT3 protein expression was measured in different brain areas involved in reward or mood regulation (such as the striatum, the hippocampus, and raphe nuclei) and genetic variations in Slc17a8, the gene encoding for VGLUT3, have been explored. These five inbred mouse strains express very different levels of VGLUT3, which cannot be attributed to the genetic variation of the Slc17a8 locus. Furthermore, mice behavior in the open field, elevated plus maze, spontaneous‐ and cocaine‐induced locomotor was highly heterogeneous and only partially correlated to VGLUT3 levels. These data highlight the fact that one single gene polymorphism could not account for VGLUT3 expression variations, and that region specific VGLUT3 expression level variations might play a key role in the modulation of discrete behaviors. 相似文献