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941.
Elena B. Rodriguez de Turco Marie Therese Droy-Lefaix Nicolas G. Bazan 《Journal of neurochemistry》1993,61(4):1438-1444
Abstract: The effect of Ginkgo biloba extract (EGb 761) treatment (100 mg/kg/day, per os, for 14 days) on electroconvulsive shock (ECS)-induced accumulation of free fatty acids (FFA) and diacylglycerols (DAG) was analyzed in rat cerebral cortex and hippocampus. EGb 761 reduced the FFA pool size by 33% and increased the DAG pool by 36% in the hippocampus. These endogenous lipids were unaffected in cerebral cortex. During the tonic seizure (10 s after ECS) the fast accumulation of FFA, mainly 20:4, was similar in sham- and EGb 761 -treated rats, in both the cerebral cortex and hippocampus. However, further accumulation of free 18:0 and 20:4, observed in the hippocampus of sham-treated rats during clonic seizures (30 s to 2 min after ECS), did not occur in EGb 761-treated animals. The rise in DAG content triggered in the cortex and hippocampus by ECS was delayed by EGb 761 treatment from 10 s to 1 min, when values similar to those in sham animals were attained. Moreover, in the hippocampus the size of the total DAG pool was decreased by 19% during the tonic seizure. At later times, DAG content showed a faster decrease in EGb 761-treated rats. By 2 min levels of all DAG acyl groups decreased to values significantly lower than in sham animals in both cortex and hippocampus. This study shows that EGb 761 treatment affects, with high selectivity, lipid metabolism and lipid-derived second messenger release and removal in the hippocampus, while affecting to a lesser extent the cerebral cortex. 相似文献
942.
Lina Jakutyte-Giraitiene Giedrius Gasiunas 《Journal of industrial microbiology & biotechnology》2016,43(8):1183-1188
Clustered regularly interspaced short palindromic repeats (CRISPR) together with CRISPR-associated (cas) genes form an adaptive prokaryotic immune system which provides acquired resistance against viruses and plasmids. Bacillus subtilis presently is the best-characterized laboratory model for Gram-positive bacteria and also widely used for industrial production of enzymes, vitamins and antibiotics. In this study, we show that type II-A CRISPR-Cas system from Streptococcus thermophilus can be transferred into B. subtilis and provides heterologous protection against phage infection. We engineered a heterologous host by cloning S. thermophilus Cas9 and a spacer targeting bacteriophage SPP1 into the chromosome of B. subtilis, which does not harbor its own CRISPR-Cas systems. We found that the heterologous CRISPR-Cas system is functionally active in B. subtilis and provides resistance against bacteriophage SPP1 infection. The high efficiency of the acquired immunity against phage could be useful in generation of biotechnologically important B. subtilis strains with engineered chromosomes. 相似文献
943.
Since microorganisms normally co-exist with other species in nature, they have developed complex metabolic and physiological
responses as a result of such interspecies interactions. We utilized some of these interactions by introducing heat-killed
cells of Bacillus subtilis and Staphylococcus aureus to Streptomyces coelicolor cultures and, as a result, stimulated undecylprodigiosin production. Undecylprodigiosin is not only an antibiotic; it has
also been attributed with antitumor activities, but, in a defined medium, pure cultures of S. coelicolor produced only low concentrations. Elicitation with B. subtilis increased the maximum undecylprodigiosin concentration by threefold and S. aureus by fivefold compared with the pure culture of S. coelicolor. Growth and glucose consumption of elicited S. coelicolor, however, remained similar to those observed in the pure culture. Furthermore, another positive outcome of the elicitation
with both B. subtilis and S. aureus was the earlier onset of undecylprodigiosin production by 24 h compared with the pure culture of S. coelicolor. This is the first time that such a phenomenon has been seen in 2L bioreactors. Our work supports the use of biotic elicitation
in order to enhance the production of secondary metabolites for industrial-scale applications. 相似文献
944.
Ruiling Liu Meiqin Liu Jie Liu Yuzhen Chen Yiyin Chen Cunfu Lu 《Plant Growth Regulation》2010,60(2):163-168
A late embryogenesis abundant protein gene, AmLEA from Ammopiptanthus mongolicus, was introduced into Escherichia coli using the IMPACT™-TWIN system to analyze the possible function of AmLEA under heat and cold stresses. A fusion protein about 38 kD was expressed in E.coli cells harboring pTWIN-LEA after the induction of IPTG by SDS–PAGE analysis and the accumulation of the fusion protein peaked
3 h after IPTG addition when cultured at 37°C. Compared with control cells, the E. coli cells expressing AmLEA fusion protein showed improved chilling and heat resistence, illuminating the protein may play a protective
role in cells under stress conditions. These results suggested the natively unstructured protein, similar to other members
of LEA proteins, has high capacity for binding water and potential protective function against dehydration or action similar
to the cold shock chaperones. 相似文献
945.
Pedro Del Bianco Benedeti Lorrayny Galoro da Silva Eduardo Marostegan de Paula Teshome Shenkoru Marcos Inácio Marcondes Hugo Fernando Monteiro Brad Amorati Yenling Yeh Simon Roger Poulson Antonio Pinheiro Faciola 《PloS one》2015,10(11)
The objective of this study was to evaluate the effects of partially replacing dry ground corn with glycerin on ruminal fermentation using a dual-flow continuous culture system. Six fermenters (1,223 ± 21 ml) were used in a replicated 3x3 Latin square arrangement with three periods of 10 d each, with 7 d for diet adaptation and 3 d for sample collections. All diets contained 75% concentrate and three dietary glycerin levels (0, 15, and 30% on dry matter basis), totaling six replicates per treatment. Fermenters were fed 72 g of dry matter/d equally divided in two meals/d, at 0800 and 2000 h. Solid and liquid dilution rates were adjusted daily to 5.5 and 11%/h, respectively. On d 8, 9, and 10, samples of 500 ml of solid and liquid digesta effluent were mixed, homogenized, and stored at -20°C. Subsamples of 10 ml were collected and preserved with 0.2 mL of a 50% H2SO4 solution for later determination of NH3-N and volatile fatty acids. Microbial biomass was isolated from fermenters for chemical analysis at the end of each experimental period. Data were analyzed using the MIXED procedure in SAS with α = 0.05. Glycerin levels did not affect apparent digestibility of DM (P
Lin. = 0.13; P
Quad. = 0.40), OM (P
Lin. = 0.72; P
Quad. = 0.15), NDF (P
Lin. = 0.38; P
Quad. = 0.50) and ADF (P
Lin. = 0.91; P
Quad. = 0.18). Also, glycerin inclusion did not affect true digestibility of DM (P
Lin. = 0.35; P
Quad. = 0.48), and OM (P
Lin. = 0.08; P
Quad. = 0.19). Concentrations of propionate (P < 0.01) and total volatile fatty acids (P < 0.01) increased linearly and concentrations of acetate (P < 0.01), butyrate (P = 0.01), iso-valerate (P < 0.01), and total branched-chain volatile fatty acids, as well as the acetate: propionate ratio (P < 0.01) decreased with glycerin inclusion. Linear increases on NH3-N concentration in digesta effluent (P < 0.01) and on NH3-N flow (P < 0.01) were observed due to glycerin inclusion in the diets. Crude protein digestibility (P = 0.04) and microbial N flow (P = 0.04) were greater in the control treatment compared with the other treatments and responded quadratically with glycerin inclusion. Furthermore, the inclusion of glycerin linearly decreased (P = 0.02) non-ammonia N flow. Glycerin levels did not affect the flows of total N (P
Lin. = 0.79; P
Quad. = 0.35), and dietary N (P
Lin. = 0.99; P
Quad. = 0.07), as well as microbial efficiency (P
Lin. = 0.09; P
Quad. = 0.07). These results suggest that partially replacing dry ground corn with glycerin may change ruminal fermentation, by increasing total volatile fatty acids, and propionate concentration without affecting microbial efficiency, which may improve glucogenic potential of beef cattle diets. 相似文献
946.
947.
In the Netherlands, high traffic density and intensive animal husbandry have led to high emissions of reactive nitrogen (N) into the environment. This leads to a series of environmental impacts, including: (1) nitrate (NO3) contamination of drinking water, (2) eutrophication of freshwater lakes, (3) acidification and biodiversity impacts on terrestrial ecosystems, (4) ozone and particle formation affecting human health, and (5) global climate change induced by emissions of N2O. Measures to control reactive N emissions were, up to now, directed towards those different environmental themes. Here we summarize the results of a study to analyse the agricultural N problem in the Netherlands in an integrated way, which means that all relevant aspects are taken into account simultaneously. A simple N balance model was developed, representing all crucial processes in the N chain, to calculate acceptable N inputs to the farm (so-called N ceiling) and to the soil surface (application in the field) by feed concentrates, organic manure, fertiliser, deposition, and N fixation. The N ceilings were calculated on the basis of critical limits for NO 3 concentrations in groundwater, N concentrations in surface water, and ammonia (NH3) emission targets related to the protection of biodiversity of natural areas. Results show that in most parts of the Netherlands, except the western and the northern part, the N ceilings are limited by NH 3 emissions, which are derived from critical N loads for nature areas, rather than limits for both ground- and surface water. On the national scale, the N ceiling ranges between 372 and 858 kton year(-1) depending on the choice of critical limits. The current N import is 848 kton year(-1). A decrease of nearly 60% is needed to reach the ceilings that are necessary to protect the environment against all adverse impacts of N pollution from agriculture. 相似文献
948.
Kinship and friendship are key human relationships. Increasingly, data suggest that people are not less altruistic toward friends than close kin. Some accounts suggest that psychologically we do not distinguish between them; countering this is evidence that kinship provides a unique explanatory factor. Using the Implicit Association Test, we examined how people implicitly think about close friends versus close kin in three contexts. In Experiment 1, we examined generic attitudinal dispositions toward friends and family. In Experiment 2, attitude similarity as a marker of family and friends was examined, and in Experiments 3 and 4, strength of in-group membership for family and friends was examined. Findings show that differences exist in implicit cognitive associations toward family and friends. There is some evidence that people hold more positive general dispositions toward friends, associate attitude similarity more with friends, consider family as more representative of the in-group than friends, but see friends as more in-group than distant kin. 相似文献
949.
Shu Jia Baoman Li Jingyang Huang Alexei Verkhratsky Liang Peng 《Neurochemical research》2018,43(8):1692-1701
Here we present the data indicating that chronic treatment with three antibipolar drugs, lithium, carbamazepine and valproic acid regulates Cav-1/PTEN/PI3K/AKT/GSK-3β signalling pathway and glycogen content in primary cultured astrocytes. All three drugs down-regulate gene expression of Caveoline 1 (Cav-1), decrease membrane content of phosphatase and tensin homolog (PTEN), increase activity of phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and serine-threonine kinase (AKT), and elevate glycogen synthase kinase 3β (GSK-3β) phosphorylation thus suppressing its activity. As expected, treatment with any of these three drugs increases glycogen content in astrocytes. Our findings indicate that regulation of glycogen content via Cav-1/PTEN/AKT/GSK-3β pathway by the three anti-bipoar drugs may be responsible for therapeutic effects of these drugs, and Cav-1 is an important signal element that may contribute to pathogenesis of various CNS diseases and regulation of its gene expression may be one of the underlying mechanisms of drug action for antibipolar drugs and antidepressants currently in clinical use. 相似文献
950.
Annerieke C van Groenestijn Ingrid GL van de Port Carin D Schröder Marcel WM Post Hepke F Grupstra Esther T Kruitwagen Harmen van der Linde Reinout O van Vliet Margreet GH van de Weerd Leonard H van den Berg Eline Lindeman 《BMC neurology》2011,11(1):1-11