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Elena Neagu Gabriel Lucian Radu Camelia Albu Gabriela Paun 《Saudi Journal of Biological Sciences》2018,25(3):578-585
In this study several investigations and tests were performed to determine the antioxidant activity and the acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% ethanol), respectively. Moreover, for each type of the prepared extracts of P. officinalis and of C. umbellatum the content in the biologically active compounds – polyphenols, flavones and proanthocyanidins was determined. The antioxidant activity was assessed using two methods, namely the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and reducing power assay. The analyzed plant extracts showed a high acetylcholinesterase and tyrosinase inhibitory activity in the range of 72.24–94.24% (at the highest used dose – 3 mg/mL), 66.96% and 94.03% (at 3 mg/mL), respectively correlated with a high DPPH radical inhibition – 70.29–84.9% (at 3 mg/mL). These medicinal plants could provide a potential natural source of bioactive compounds and could be beneficial to the human health, especially in the neurodegenerative disorders and as sources of natural antioxidants in food industry. 相似文献
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Lucian Hritcu Marius Stefan Roderich Brandsch Marius Mihasan 《Journal of physiology and biochemistry》2013,69(1):25-34
Male Wistar rats were subjected to chronic 6-hydroxy-l-nicotine treatment (6HLN, 0.3 mg/kg, i.p., seven consecutive days) and their memory performance was studied by means of Y-maze and radial arm-maze tasks. 6HLN significantly increased spontaneous alternations in Y-maze task and working memory in radial arm-maze task, suggesting effects on short-term memory, without affecting long-term memory, explored by reference memory in radial arm-maze task. In addition, 6HLN increased antioxidant enzymes activity and decreased production of lipid peroxidation, suggesting antioxidant effects. Also, the linear regression between behavioral measures and oxidative stress markers resulted in significant correlations. Therefore, positive effects of 6HLN on spatial memory may occur by antioxidant actions. 相似文献
5.
Lactuca capensis reverses memory deficits in Aβ1‐42‐induced an animal model of Alzheimer's disease 下载免费PDF全文
Paula Alexandra Postu Jaures A. K. Noumedem Oana Cioanca Monica Hancianu Marius Mihasan Mitica Ciorpac Dragos Lucian Gorgan Brindusa Alina Petre Lucian Hritcu 《Journal of cellular and molecular medicine》2018,22(1):111-122
We investigated the neuropharmacological effects of the methanolic extract from Lactuca capensis Thunb. leaves (100 and 200 mg/kg) for 21 days on memory impairment in an Alzheimer's disease (AD) rat model produced by direct intraventricular delivery of amyloid‐β1‐42 (Aβ1‐42). Behavioural assays such as Y‐maze and radial arm maze test were used for assessing memory performance. Aβ1‐42 decreased cognitive performance in the behavioural tests which were ameliorated by pre‐treatment with the methanolic extract. Acetylcholinesterase activity and oxidant–antioxidant balance in the rat hippocampus were abnormally altered by Aβ1‐42 treatment while these deficits were recovered by pre‐treatment with the methanolic extract. In addition, rats were given Aβ1‐42 exhibited in the hippocampus decreased brain‐derived neurotrophic factor (BDNF) mRNA copy number and increased IL‐1β mRNA copy number which was reversed by the methanolic extract administration. These findings suggest that the methanolic extract could be a potent neuropharmacological agent against dementia via modulating cholinergic activity, increasing of BDNF levels and promoting antioxidant action in the rat hippocampus. 相似文献
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Lucian J. Cuprak Carol J. Lammi Janet I. Crane 《In vitro cellular & developmental biology. Plant》1979,15(11):900-909
Summary An improved basal medium is presented that requires only minimal supplementation with dialyzed fetal bovine serum or bovine
serum albumin and fetuin to be comparable to Ham's F-10, which requires 15% horse serum (HS) and 2.5% fetal bovine serum (FBS)
for the growth and function of Y-1, mouse adrenal cortex tumor, cells. Cell monolayers maintained for up to 2 weeks without
any protein supplementation have retained their steroid response to ACTH. The medium differs from Ham's F-10 in its buffer
composition and higher calcium-ion concentration. This medium should be a useful adjunct to studies pertaining to steroid
and lipid intermediary metabolism, the retention of a specialized physiological function in a chemically defined medium, and
the mechanism of hormonal response.
Supported by the Medical Research Service of the Veterans Administration. 相似文献
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Wang Z Heshka S Wang J Wielopolski L Heymsfield SB 《American journal of physiology. Endocrinology and metabolism》2003,284(2):E267-E273
The mean density of fat-free mass (FFM) is remarkably stable at 1.10 g/cm(3) in healthy adult humans, and this stability is a cornerstone of the widely applied densitometry-based two-compartment model for estimating total body fat. At present, the usual means of exploring FFM density is by in vitro or in vivo experimental studies. The purpose of the present investigation was to develop a cellular-level body composition model that includes seven factors that determine FFM density. The model, when applied with available empirical coefficients, predicted an FFM density similar to that observed in vivo. An analysis of the seven model components indicates that the ratio of extracellular solids to total body water is a major determinant of individual variation in FFM density. The difference in FFM density across sex, race, and age groups was examined with the developed model. The present study thus provides a conceptual framework for the systematic study of FFM density in humans. 相似文献
10.
Christian Schobert Lucian Baker Judit Szederkényi Pia Großmann Ewald Komor Hiroaki Hayashi Mitsuo Chino William J. Lucas 《Planta》1998,206(2):245-252
The mature, functional sieve-tube system in higher plants is dependent upon protein import from the companion cells to maintain
a functional long-distance transport system. Soluble proteins present within the sieve-tube lumen were investigated by analysis
of sieve-tube exudates which revealed the presence of distinct sets of polypeptides in seven monocotyledonous and dicotyledonous
plant species. Antibodies directed against sieve-tube exudate proteins from Ricinus communis L. demonstrated the presence of shared antigens in the phloem sap collected from Triticum aestivum L., Oryza sativa L., Yucca filamentosa L., Cucurbita maxima Duch., Robinia pseudoacacia L. and Tilia platyphyllos L. Specific antibodies were employed to identify major polypeptides. Molecular chaperones related to Rubisco-subunit-binding
protein and cyclophilin, as well as ubiquitin and the redox proteins, thioredoxin h and glutaredoxin, were detected in the
sieve-tube exudate of all species examined. Actin and profilin, a modulator of actin polymerization, were also present in
all analyzed phloem exudates. However, some proteins were highly species-specific, e.g. cystatin, a protease-inhibitor was
present in R. communis but was not detected in exudates from other species, and orthologs of the well-known squash phloem lectin, phloem protein
2, were only identified in the sieve-tube exudate of R. communis and R. pseudoacacia. These findings are discussed in terms of the likely roles played by phloem proteins in the maintenance and function of the
enucleate sieve-tube system of higher plants.
Received: 12 February 1998 / Accepted: 16 March 1998 相似文献