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1.
The effect of a plum ethanol extract (PEE) on immunity was analyzed. An oral administration of PEE increased the interleukin (IL)-12p40 concentration in the serum and T-cell ratio in the spleen. In vitro studies revealed that PEE stimulated IL-12p70 production in peritoneal macrophages and natural killer activity. These findings suggest that PEE enhanced the immune function by stimulating innate immune cells. 相似文献
2.
目的研究噬菌蛭弧菌代谢产物活性成分对小鼠免疫功能的影响。方法将噬菌蛭弧菌代谢产物的3种有机溶剂(石油醚、三氯甲烷、乙酸乙酯)提取物和提取后的剩余液体分别腹腔注射实验小鼠,分两次注射,共注射0.5 mL,注射后连续饲养28 d,每隔7 d小鼠采血检测离体白细胞吞噬活性(phagocytic activity)、吞噬细胞杀菌活性(bactericidal activity)、超氧化物歧化酶(superoxide dismutase,SOD)活性、血清凝集抗体效价、血红蛋白值和红细胞数的变化,以研究不同提取物对小鼠免疫功能的影响。结果石油醚提取物组和三氯甲烷提取物组小鼠血清SOD活性、血清凝集抗体效价、离体白细胞吞噬活性和吞噬细胞杀菌活性增强与对照组相比差异极显著(P〈0.01);乙酸乙酯提取物组SOD活性和血清凝集抗体效价增强与对照组相比差异极显著(P〈0.01),离体白细胞吞噬活性和吞噬细胞杀菌活性增强与对照组相比差异显著(P〈0.05);石油醚提取物组的血红蛋白值(12.64 g/100 mL)和红细胞数(11.32×106/mL)最高。各项指标的峰值均出现在第7天~第21天。结论噬菌蛭弧菌代谢产物3种有机溶剂提取的活性物质具有增强小鼠免疫功能的作用。 相似文献
3.
Ibrahim Alfarrayeh Csaba Fekete Zoltn Gazdag Gbor Papp 《Saudi Journal of Biological Sciences》2021,28(1):1033
This study investigated the in vitro effect of propolis ethanolic extract (PEE) on planktonic growth and biofilm forming abilities of five commercial probiotics (Enterol, Protexin, Normaflore, BioGaia and Linex). Broth microdilution method was used to investigate the susceptibility of the microbes of five commercial probiotics to PEE. Crystal violet assay was used for the quantitative assessment of biofilm formation and mature biofilm eradication tests. Effect of PEE on autoaggregation ability and swarming motility of Normaflore microbes was determined. Planktonic forms of probiotics showed varied susceptibilities with minimal inhibitory concentration values in the range of 100–800 µg/mL of PEE. However, low PEE concentrations significantly enhanced the planktonic growth of Linex and BioGaia microbes. Biofilm studies revealed that Enterol and Protexin were non-biofilm formers, while BioGaia, Linex and Normaflore showed weak biofilms, which were inhibited by 12.5, 25, and 800 µg/mL of PEE, respectively. PEE revealed double-face effect on the biofilms of Normaflore and Linex, which were enhanced at low concentrations of PEE and inhibited at higher concentrations. Interestingly, Normaflore biofilms were shifted from weak to strong biofilms at low PEE concentrations (12.5, 25, and 50 µg/mL). In conclusion, PEE has strain dependent controversial effects on the planktonic growth and biofilm forming ability of the tested probiotics, although high concentrations have inhibitory effect on all of them, low concentrations may have strain dependent prebiotic effect. 相似文献
4.
A Mavri H Abramovič T Polak J Bertoncelj P Jamnik S Smole Možina B Jeršek 《Chemistry & biodiversity》2012,9(8):1545-1558
The chemical composition as well as the antioxidant and antimicrobial activities of two EtOH extracts of propolis (PEEs) from Slovenia were determined. EtOH was used as extracting solvent at 70 and 96%, providing the extracts PEE70 and PEE96, respectively. The extraction with 70% EtOH was more efficient than that with 96% EtOH, as the PEE70 was richer in total phenolic compounds than the PEE96. The Slovenian propolis was characterized by different phenolic acids and flavonoids. The PEE96 was slightly richer in three specific compounds, i.e., caffeic acid, ferulic acid, and luteolin, while all other substances detected showed higher contents in the PEE70. The PEE70 showed a stronger reducing power and ability to scavenge free radicals and metal ions than the PEE96. Both PEEs were in the main more effective against Gram-positive bacteria than against fungi and Gram-negative bacteria like Salmonella and Escherichia coli, with the exception of Campylobacter. The PEE96 decreased the intracellular oxidation in Saccharomyces cerevisiae in a dose-dependent manner. The antimicrobial activities and antioxidant properties were related to the total phenolic contents. The two PEEs have the potential for use as natural antimicrobial and antioxidant additives in foods. 相似文献
5.
Hocková D Holý A Andrei G Snoeck R Balzarini J 《Bioorganic & medicinal chemistry》2011,19(15):4445-4453
Series of novel acyclic nucleoside phosphonates (ANPs) with various nucleobases and 2-(2-phosphonoethoxy)ethyl (PEE) chain bearing various substituents in β-position to the phosphonate moiety were prepared. The influence of structural alternations on antiviral activity was studied. Several derivatives exhibit antiviral activity against HIV and vaccinia virus (middle micromolar range), HSV-1 and HSV-2 (lower micromolar range) and VZV and CMV (nanomolar range), although the parent unbranched PEE-ANPs are inactive. Adenine as a nucleobase and the methyl group attached to the PEE chain proved to be a prerequisite to afford pronounced antiviral activity. 相似文献
6.
南瓜醇提物的体外抗氧化活性(英文) 总被引:1,自引:0,他引:1
采用化学体系模拟法体外测定南瓜醇提物((pumpkin ethanol extract,PEE)对1,1-二苯基-2-苦苯肼自由基(DPPH·)、超氧阴离子自由基(O2)和羟自由基(·OH)的清除能力,总还原力,对β-胡萝卜素/亚油酸自氧化体系的总抗氧化能力以及脂质过氧化的抑制能力.结果显示PEE对DPPH·、02-和·OH均有较强的清除能力,IC50值分别为18.8 mg/mL、29.0 ms/mL和44.9μg/mL,有显著的还原力和总抗氧化力,对脂质过氧化有一定的抑制作用.PEE的体外抗氧化活性均有良好的量效关系.上述结果为南瓜作为抗氧化的保健食品或功能食品开发利用提供了依据. 相似文献
7.
《Saudi Journal of Biological Sciences》2021,28(10):5745-5753
Seaweeds have been focused as potential and promising resources to develop novel pharmaceuticals. The present study was aimed to investigate the bioactive principles of Sargassum crassifolium (S. crassifolium) through organic solvents methanol and petroleum ether extractions individually. The present study also extended to determine the antibacterial potentiality of the bioactive principles from methanolic extract (ME) and petroleum ether extract (PEE) of S. crassifolium against a set of human pathogenic bacteria. Gas chromatography-mass spectrometry (GC–MS) and Fourier transform infrared spectroscopy (FT-IR) analysis of the ME and PEE were exhibiting unique bioactive constituents. The antibacterial effect of ME and PEE were showed the moderate spectrum of activity when compared to the standard streptomycin disc against the screened human pathogenic bacteria. The bacterial sensitivity to the ME was sequenced as Bacillus subtilis > Pseudomonas aeruginosa > Escherichia coli > Klebsiella pneumoniae > Staphylococcus aureus > Streptococcus pyogenes. Furthermore, the spectrum of activity of PEE was showing more or less similar pattern of action with almost equal potency. The spectrum of activity of PEE extract was in the order Bacillus subtilis > Pseudomonas aeruginosa > Escherichia coli > Staphylococcus aureus > Streptococcus pyogenes > Klebsiella pneumoniae. 相似文献
8.
Objective: To examine the effects of methylphenidate hydrochloride (MPH) on resting energy expenditure (REE) and postprandial energy expenditure (PEE) and substrate partitioning. Methods and Procedures: Seven healthy men and seven healthy women participated in this double‐blind, randomized, placebo‐controlled, crossover study. MPH (0.5 mg/kg) or placebo was administered orally in the fasting state, 60 min before a REE measurement, and 90 min before a standardized breakfast of ~650 kcal. REE, PEE, and respiratory exchange ratio (RER) were obtained from indirect calorimetry. Body composition was measured using DEXA. Vital signs (blood pressure (BP) and heart rate (HR)) were assessed pre‐ and post‐administration of MPH or placebo in every session. Results: During the, MPH condition, REE increased over values observed during the placebo session (7%, P < 0.001). No changes in fasting RER were noted. Although PEE continually decreased with time as expected, MPH treatment resulted in significantly greater PEE values at 90 min (5%, P < 0.01). No significant effects of MPH were found for vital signs (HR, systolic, and diastolic BP). Discussion: MPH causes a significant increase in both REE and PEE without the significant changes in HR and BP that are commonly associated with psychostimulant use. 相似文献
9.
Unit activity was studied in the gigantocellular nucleus of decerebrate cats after injection of tetanus toxin into the nucleus. The toxin was used to disturb inhibition. An increase in amplitude and frequency of unit discharges, a marked increase in integral spontaneous and, in particular, evoked activity, an increase in the number of neurons with a "burst" type of activity, and prolonged maintenance of enhanced evoked activity were recorded in the poisoned nucleus. The increased activity in the part of the poisoned nucleus studied could be temporarily suppressed by injection of glycine into the nucleus or by strong direct electrical stimulation. It can be concluded from the results that a population of neurons with disturbed inhibitory connections forms an excitation generator. The nature of operation of such a generator is discussed and the possibility of simulating neurological syndromes by the creation of such generators in various parts of the CNS is argued. 相似文献
10.
Measures of geographic range size: the effects of sample size 总被引:2,自引:0,他引:2
A number of methods have been used for quantifying the sizes of the geographic ranges of species. The consequences of different levels of sampling (the proportion of actual spatial occurrences) are explored for eight of these, using data on the occurrences of butterfly species on a 10 × 10 km grid across Britain. For all methods, the percentage error of estimation (PEE) decreases with the number of 10 × 10 km squares which a species occupies, most rapidly for extent measures, and more rapidly for area measures than for measures of numbers of units occupied. The rate of decline in PEE itself falls as sampling effort increases. At a given sampling level, rank correlations between range sizes measured by different methods are generally high, but there is no consistent change in the magnitude of these correlations as the level of sampling increases. The composition of the set of species with the smallest range sizes changes with the level of sampling. 相似文献
11.
《Saudi Journal of Biological Sciences》2023,30(6):103663
Piper chaba, a traditional South-east Asian medicinal herb and well-known curry spice, was studied to evaluate its suitability as a source of natural preservatives for beef products. Plant extracts that are high in phenolics and have high antimicrobial and antioxidant activities are likely to be useful as a natural preservative. Therefore, the phytochemical composition and the bioactivities of both ethanolic and methanolic extracts of P. chaba stem were examined first. The study revealed a significant antioxidant activities and potential antibacterial activity of P. chaba extracts. Next we investigated the preservation characteristics of P. chaba by using beef patties as a model system. Beef patties were produced and treated with 0.2 % ethanolic extract (mentioned as PEE) of P. chaba and 0.1 % commercial preservative (mentioned as PCP). They were then assessed for various storage quality parameters under refrigerated (4° C ± 1° C) conditions, including free fatty acid, antioxidant contents, and oxidative stability at 0, 6th, 16th, and 33rd days. No significant variations were observed across the products with regard to proximate composition study such as protein, ash and fat contents. In comparison to both PEE and PCP, the control product had higher free fatty acid values throughout the storage period. This indicates that the fat content of the PEE and PCP degraded at a slower rate than the control over the 33-day storage period. Our study also showed that both PCP and PEE had increased antioxidant capacity, implying that lipid oxidation is minimized. In contrast to the control, the oxidative stability of the P. chaba treated products was also higher. Altogether this study revealed that P. chaba could be utilized commercially, particularly in the food industry to preserve muscle foods.Practical ApplicationsNatural preservatives are becoming more popular as a result of the different carcinogenic and toxic side effects of conventional preservatives. P. chaba, an exquisite culinary herb in Bangladesh, has long been used as a traditional medicine, because of its antimicrobial and antioxidant properties. This study revealed that P. chaba can be utilized as a food preservative, which opens up new possibilities for its development and use in functional foods. 相似文献
12.
Propolis ethanolic extract (PEE) at 3 and 4 g/L and ultragriseofulvin (UG) at 0.75 and 1 g/L reduced the percentage of conidia
germination in twoAspergillus flavus isolates. PEE at 1–4 g/L decreased the mycelial dry mass ofA. flavus isolates by 11–80%, and aflatoxin B1 production by 34–100%. UG concentrations of 0.25–1 g/L reduced the growth and aflatoxin B1 production of the isolates by 16–88 and 48–98%, respectively. Any increase in PEE and UG concentration was accompanied by
a clear decrease in the per cent conidia germination, growth and aflatoxin B1 production. At equal concentration, UG was about 4-times more effective than PEE. 相似文献
13.
Prenatal ethanol exposure (PEE) can lead to structural and functional abnormalities in fetal brain. Although neural developmental deficits due to PEE have been recognized, the immediate effects of PEE on fetal brain vasculature and hemodynamics remain poorly understood. One of the major obstacles that preclude the rapid advancement of studies on fetal vascular dynamics is the limitation of the imaging techniques. Thus, a technique for noninvasive in‐vivo imaging of fetal vasculature and hemodynamics is desirable. In this study, we explored the dynamic changes of the vessel dimeter, density and oxygen saturation in fetal brain after acute maternal ethanol exposure in the second‐trimester equivalent murine model using a real‐time photoacoustic tomography system we developed for imaging embryo of small animals. The results indicate a significant decrease in fetal brain vessel diameter, perfusion and oxygen saturation. This work demonstrated that PAT can provide high‐resolution noninvasive imaging ability to monitor fetal vascular dynamics. 相似文献
14.
Courtship clasping, a reproductive behavior in male roughskin newts (Taricha granulosa), is rapidly blocked by an action of corticosterone (CORT) at a specific neuronal membrane receptor. The CORT-induced impairment of clasping in behaving newts appears to be mediated partly by an elimination of clasping-related activity in medullary reticulospinal neurons. Previous studies of rapid CORT actions in Taricha have focused on the brain, so existence of CORT action in the spinal cord or peripheral nervous system has not been assessed. The present study used newts with a high cervical spinal transection to examine potential spinal or peripheral CORT effects on clasping by the hindlimbs in response to pressure on the cloaca. Spinal transection causes clasps elicited by cloacal stimulation to be very sustained beyond the termination of the eliciting stimulus. In spinally transected newts, CORT caused a dose-dependent depression in the duration as well as quality of the clasp that appeared within 10 min of injection. CORT selectively impaired the usual sustained maintenance of a clasp after termination of cloacal stimulation, but not clasp elicitation during stimulation. These effects were not produced by dexamethasone, a synthetic glucocorticoid that binds poorly to the CORT membrane receptor. The CORT effect on clasp maintenance but not clasp elicitation implies selective action on an intraspinal generator for clasping but not on sensory or efferent neuromuscular aspects of the response. These results indicate the presence in the newt spinal cord of the CORT membrane receptor that exerts functional effects distinctly different from those on the brainstem. 相似文献
15.
Hui-xiao Yang Rui Luo Fen-cheng Zhao Tian-yi Liu Chun-xin Liu Shao-wei Huang 《Trees - Structure and Function》2013,27(5):1429-1442
A total of 122 F1 individuals from a single full-sib interspecific hybrid family crossed between Pinus elliottii var. elliottii (PEE) and P. caribaea var. hondurensis (PCH) were used to construct a detailed genetic linkage maps using four types of molecular markers: sequence-related amplified polymorphism (SRAP), microsatellite (SSR), expressed sequence tag polymorphism (ESTP) and inter-simple sequence repeat (ISSR). There were 381 SRAP, 108 SSR, 25 ESTP and 32 ISSR loci, segregating in the interspecific F1 hybrid individuals. Framework maps were constructed at a LOD score threshold of 4.0 using the JoinMap® 3.0. The map for the male parent (PCH) had 108 markers in 16 linkage groups (LGs), with a total length of 1,065.9 cM (Kosambi) and an average marker interval of 9.87 cM. The map for the female parent (PEE) contained 93 markers in 19 LGs, with a total length of 1,006.7 cM (Kosambi) and an average marker interval of 10.82 cM. The maps for PCH and PEE covered 56.5 and 70.3 % of their respective genomes. Based on the position of 36 loci segregating in both parents, 8 homologous LGs between PEE and PCH were identified. 相似文献
16.
Gelatin-catechin conjugate was synthesized by the laccase-catalyzed oxidation of catechin in the presence of gelatin. The conjugate had a good scavenging activity against superoxide anion radicals. Moreover, the conjugate showed an amplified inhibition effect on human low density lipoprotein oxidation initiated by 2,2'-azobis(2-amidinopropane)dihydrochloride as a radical generator. 相似文献
17.
Valérie S Fénelon Béatrice Casasnovas John Simmers Pierre Meyrand 《Current opinion in neurobiology》1998,8(6):705-709
In contrast to the wealth of knowledge about the organizational rules of adult central pattern generators, far less is known about how these networks are assembled during development. The basic architecture for adult central pattern generators appears early in development but different generators may follow completely different developmental pathways to reach maturity. Recent evidence suggests that neuromodulatory inputs, in addition to their short-term adaptive control of central pattern generator activity, play a crucial role in both the final developmental tuning and the long-term maintenance of adult network function. 相似文献
18.
S I Igon'kina G N Kryzhanovskii 《Biulleten' eksperimental'no? biologii i meditsiny》1979,88(9):278-281
In experiments on white rats the generator of excitation was created in the dorsal raphe nucleus by microinjection of tetanus toxin. After formation of the excitation generator electrical activity in this nucleus was changed as the following: the first negative component (N1) was strongly increased, general EP configuration changed and the spontaneous paroxysmal activity became more frequent. The time of the generator formation correlated with the appearance of intense and prolonged analgesia. Naloxone did not reverse the effects of analgesia described. 相似文献
19.
Studies have been made on the inhibitory effect of ouabain solutions on bioelectrical activity of the labellar sensillae of flied. It was shown that 10(-2) M ouabain solution irreversibly inhibits the activity, where as 10(-3) and 10(-4) M concentrations decrease the frequency of impulses within 40-60 min. Ouabain solution is a specific stimulator of the sugar receptor of the sensillae with a threshold of 10(-7) M; in combination with 0.2 M glucose, it inhibits impulse activity with the first 200 msec of stimulation. The effect is observed in a narrow zone of ouabain concentrations, with a maximum approximately at 10(-4) M. Differences between the effects of the inhibitor at the vicinity of the onset of generator potential and those in the impulse activity zones on the membrane of the sensory cell are suggested. 相似文献
20.
A working hypothesis is proposed to account for the timing of puberty in female sheep. In the immature female, the frequency of LH pulses is low, and ovarian follicles do not develop to an advanced stage. During the pubertal transition, the frequency of LH pulses increases to drive follicular development and the production of oestradiol which evokes the gonadotrophin surge and ovulation. Central to the hypothesis is the hypothalamic pulse generator for GnRH that directs the pattern and level of LH secretion. Growth-related cues are monitored to regulate the activity of the GnRH pulse generator. When a sufficient body size is attained, the frequency of LH pulses increases both because the sensitivity to oestradiol inhibitory feedback decreases and because the GnRH pulse generator can be accelerated by the steroid. This increase in LH pulse frequency occurs provided the female has experienced the requisite exposure to photoperiod, i.e. the long days of summer followed by the short days of autumn. These photoperiodic cues are transduced by the pineal gland into a humoral signal which is an increased nocturnal production of melatonin. Failure to grow to the appropriate body size or to experience the appropriate exposure to photoperiod leads to a maintenance of the prepubertal anovulatory condition because the GnRH pulse generator operates at low frequency. 相似文献