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841.
本实验研究了饲料中添加乌贼肝粉和鱼浆蛋白对中华鳖抗氧化能力的影响。设计了3个实验组,对照组(白鱼粉组)、乌贼肝粉组和鱼浆蛋白组。3种实验饲料的营养成分相近,主要区别是乌贼肝粉组和鱼浆蛋白组的饲料中分别用乌贼肝粉和鱼浆蛋白取代了对照组饲料中5%的白鱼粉。用3种饲料分别养殖中华鳖(Pelodiscus sinensis)稚鳖8周,测定了稚鳖血清和肝组织的超氧化物歧化酶(SOD)活性、丙二醛含量(MDA)、总抗氧化能力(T-AOC)以及血清碱性磷酸酶(AKP)和溶菌酶(LZM)的活性。结果发现,乌贼肝粉组稚鳖血清和肝MDA含量显著低于对照组,T-AOC高于对照组;鱼浆蛋白组稚鳖血清和肝MDA含量、血清T-AOC与对照组没有显著差异,但肝T-AOC显著低于对照组。实验结果表明,饲料中添加5%的乌贼肝粉能提高稚鳖的抗氧化能力。  相似文献   
842.
The present study sought to evaluate the central nervous system (CNS) depressant, antioxidant, and cytotoxicity activity of methanol and aqueous extract of Trametes versicolor (METV and AETV). The CNS activity was assessed by the open field, hole-cross, forced swimming, thiopental sodium-induced sleeping time, hole-board, and rotarod tests in Swiss albino mice. For both extracts, a substantial decrease in locomotion was observed in open field and hole-cross tests. In addition, the molecular docking study has been implemented through Maestro V11.1. The higher dose of METV (400 mg/kg) and the lower dose of AETV (200 mg/kg) exhibited a significant decrease in immobility time in forced swimming test and increased prolongation of sleep in thiopental sodium-induced sleeping time test, respectively. In contrast, a moderate finding was observed for the hole-board and rotarod tests. Additionally, a significant DPPH scavenging assay and a high toxicity effect in brine shrimp lethality assay were observed. Besides, five phenolic compounds, namely baicalin, quercetin, catechin, p-hydroxybenzoic acid, and quinic acid, were used for the molecular docking study, whereas catechin demonstrated the highest binding affinity towards the targets. The findings conclude that the T. versicolor could be an alternative source for CNS anti-depressant and antioxidant activity.  相似文献   
843.
The present study aimed to evaluate the effect of single-bulb garlic oil (SGO) on toll-like receptors 3 and 4 (TLR3 and TLR 4) and nuclear erythroid factor-like 2 (Nrf2) signaling pathway resulted from a high-fat diet and its underlying mechanism. Twenty-four Balb/c mice allocated into six groups: 1) N: mice fed with standard chow; 2) HFD: mice fed a high-fat diet for 45 days without any treatment; 3) HFD + Simv: mice fed a high-fat diet for 45 days and treated with simvastatin; 4–6) HFD + SGO 100, 200, 400 (mice fed a high-fat diet for 45 days and treated with single-bulb garlic oil at dose: 100, 200, and 400 mg/kg body weight for 30 days), respectively. At the end of treatment, spleen and hepar were isolated. The flow cytometry analysis was performed to analyze the relative number of nrf2, superoxide dismutase (SOD), malondialdehyde (MDA), TLR3, TLR4 and interleukin (IL-17). The results showed that HFD induction significantly reduced Nrf-2 and antioxidant enzyme levels. Furthermore, HFD induction increased TLR3 and TLR4 signaling and IL-17 production. Interestingly, 200 mg/kg BW of SGO increased the relative number Nrf-2 followed by SOD and HO-1 elevation at a dose of 100 mg/kg BW. SGO100 notably decrease the relative number of TLR3 (CD11b+TLR3+) and TLR4 (CD11b+TLR4+). The production of IL-17 by CD4 and CD8 were also reduced after receiving SGO at 200 mg/kg BW. This study suggests that the protective effect of SGO treatment on HFD mice was achieved by modulating TLR-Nrf2 cross-talks and decreasing IL-17 production. Our findings support a potential beneficial role of SGO for treating metabolic disease caused by a high-fat diet.  相似文献   
844.
Current information on pancreatic islet sulfonylurea receptors has been obtained with laboratory animal pancreatic β cells or stable β-cell lines. In the present study, we evaluated the properties of sulfonylurea receptors of human islets of Langherans, prepared by collagenase digestion and density-gradient purification. The binding characterisitics of labeled glibenclamide to pancreatic islet membrane preparations were analyzed, displacement studies with several oral hypoglycemic agents were performed, and these latter compounds were tested as for their insulinotropic action on intact human islets. [3H]glibenclamide saturable binding was shown to be linear at ≤0.25 mg/ml protein; it was both temperature and time dependent. Scatchard analysis of the equilibrium binding data at 25°C indicated the presence of a single class of saturable, high-affinity binding sites with a Kd value of 1.0 ± 0.07 nM and a Bmax value of 657 ± 48 fmol/mg of proteins. The displacement experiments showed the following rank order of potency of the oral hypoglycemic agents we tested: glibenclamide = glimepiride > tolbutamide > chlorpropamide ≫ metformin. This binding potency order was parallel with the insulinotropic potency of the evaluated compounds. J. Cell. Biochem. 71:182–188, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
845.
耐寒性的高低极大程度上影响螨类的越冬存活以及分布扩散情况。螨类耐寒性评估的主要指标是过冷却点以及低温胁迫下的致死温度和致死时间。螨类耐寒性通常具有可塑性,不同发育时期、滞育、季节变化以及冷驯化均会影响耐寒性,而耐寒性的变化涉及复杂的分子水平以及生理生化物质的变化。本文简要介绍了目前评估螨类耐寒性的生物学指标以及影响螨类的耐寒性的因素,总结了螨类耐寒性变化所涉及的生理生化和分子机制,探讨了目前螨类耐寒性需要进一步研究的科学问题,并对螨类耐寒性研究的生态学意义进行了展望。以期对螨类耐寒性的深入研究提供参考,促进害螨的综合防治和天敌捕食螨的开发利用。  相似文献   
846.
Aging is a naturally biological process with adverse effects. The continuous accumulation of reactive oxygen species (ROS) trigger cellular and tissue damage by activating several aging enzymes. The antioxidant properties of traditional medicinal plants used by Jakun aborigine’s community are a promising approach to alleviate aging process and prevent Alzheimer. The aim of the current investigation was to optimize a novel anti-aging formulation from traditional plants (Cnestis palala stem, Urceola micrantha stem, Marantodes pumilum stem and Microporus xanthopus fruiting bodies) using simplex centroid mixture design (SCMD). After selecting the optimal formulations based on desirability function of antioxidant activity (DPPḢ, ABTṠ+ and FRAP), they were further examined against the activity of aging-related-enzymes (collagenase, tyrosinase, acetyl- and butyrylcholinesterase). The single extracts of C. palala, U. micrantha and the binary mixture of C. palala and U. micrantha were the optimal formulations with high antioxidant activities. Single extract of U. micrantha showed the highest inhibition towards matrix metalloproteinase-1 (49.44 ± 4.11 %), while C. palala water extract showed highest inhibitions towards tyrosinase (14.06 ± 0.31%), acetylcholinesterase (32.92 ± 2.13%) and butyrylcholinesterase (34.89 ± 2.84%) enzymes. The single extracts of C. palala and U. micrantha displayed better activity as compared to the binary mixture formulation. In conclusion, these findings could be a baseline for further exploration of novel anti-aging agents from natural resources.  相似文献   
847.
IntroductionThe use of chemical products to neutralize microorganisms has always been a subject of discussion and research for alternative solutions, indeed, the use of essential oils has been a promising natural methodology.MethodsIn our study we used the essential oils from different parts of Thapsia transtagana (Apiaceae), obtained by hydrodistillation, were identified and using Gas chromatography–mass spectrometry (GC–MS) and Gas Chromatography-Flame Ionization Detection (GC/FID) methods and evaluated against several bacteria of Gram- and Gram + bacteria. Disk diffusion, Minimum Inhibitory Concentration (MIC) and Minimum Microbicidal Concentration (MMC) methods have been used. Free radical-scavenging activity and insecticidal activity of Thapsia transtagana essential oils were also identified.ResultsMajority products from different parts of Thapsia transtagana essential oil identified by GC–MS and GC/FID methods are 2,6-Dimethylnaphthalene, Pinane and Hexahydrofarnesyl acetone. The highest activity was found against Staphylococcus aureus using inflorescence essential oil with minimal inhibitory concentration value for 0,56 μg/μL. Insecticidal activity was also the subject of this study, roots and inflorescence essential oils demonstrated to have a remarkable potent against Acanthoscelides obtectus and Sitophilus oryzae using contact assessment, inhalation assessment and ingestion assessment tests. Insecticidal activity assay results showed a significant enhancement of mortality in both test insect pest on increasing the dose and exposure period. In the other hand, the different essential oils of Thapsia transtagana were evaluated for their radical scavenging activities by means of the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay. The strongest scavenging activity was observed in inflorescences essential oil fraction scavenged radicals effectively at 100% using 500 mgL-1 concentration.ConclusionIts essential oils were proved to have strong antimicrobial, insecticidal and antioxidant activities that allows it to be used by the pharmaceutical and cosmetic industries as natural preservative.  相似文献   
848.
Taikor (Garcinia pedunculata Roxb.) is an underutilized, however nutritious fruit, typically found in Bangladesh and northeast parts of India. Taikor slices (1 ± 0.25 cm thickness) were pretreated for 10 min in 10% sucrose, 10% fructose, and 2% brine solution. Three different temperatures, such as 45, 50, and 55 °C were used to perform the drying operation at 30% constant relative humidity (RH). The thin-layer dehydration characteristics of taikor slices were analyzed using the Newtonian, Page, and Henderson and Pabi’s model. The changes in pH, total acidity, color, β-carotene, vitamin C, B vitamins, antioxidant activity, and microbial load calculation were done to compare the comprehensive quality of untreated and pre-treated dried taikor. After assessing the coefficient of determination (R2) and root mean square error (RMSE) values, the Page model was obtained as the best-suited model. For this model, the R2 and RMSE values were found to be approximately 1 and below 0.1094, respectively. Among the pretreatments, sucrose helped retain quality characteristics like ascorbic acid (115.25 ± 0.19 mg/100 g), antioxidant activity (33.25 ± 0.07%) more in the dried samples. The brine pretreated sample had minimum microbial growth. Fructose pretreated taikor samples dried at 45 °C exhibited maximum value of B vitamins (B1 0.025 ± 0.002 mg/100 g, B2 0.016 ± 0.002 mg/100 g, B3 0.011 ± 0.001 mg/100 g), total phenolic content (15.78 ± 0.15 mg GAE/100 g), total flavonoid content (11.11 ± 0.08 mg QE/100 g). Overall, fructose pretreated sample dried at 55 °C was found to be the best method for preserving the maximum physical and chemical quality of dried Garcinia pedunculata.  相似文献   
849.
850.
We report a series of tranylcypromine analogues containing a fluorine in the cyclopropyl ring. A number of compounds with additional m- or p-substitution of the aryl ring were micromolar inhibitors of the LSD1 enzyme. In cellular assays, the compounds inhibited the proliferation of acute myeloid leukemia cell lines. Increased levels of the biomarkers H3K4me2 and CD86 were consistent with LSD1 target engagement.  相似文献   
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