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71.
Ankita Varshney Yunus Ansari Nida Zaidi Ejaz Ahmad Gamal Badr Parvez Alam Rizwan Hasan Khan 《Cell biochemistry and biophysics》2014,69(1):93-101
To develop an efficient method for extracting and purifying the active ingredient, arctiin, from Fructus arctii and to investigate the protective effect of arctiin against glucose-induced rat aortic endothelial cell (RAEC) injury was investigated. Using a L9 (34) orthogonal array and two-step column chromatography (with AB-8 macroporous resin) arctiin extraction was optimized using a reflux method with 70 % ethanol. The RAECs were then treated with different concentrations of arctiin (1, 10, or 100 μg/ml). The effects of arctiin on cell viability in a high glucose medium, malondialdehyde (MDA) levels, and lactate dehydrogenase were measured using commercially available assays. After extraction, the purity of arctiin reached 95.7 %. In rats, arctiin was shown to stimulate the proliferation of RAECs in a high glucose medium in a dose-dependent manner. Exposure of RAECs to high glucose resulted in a significant increase in MDA and release of lactate dehydrogenase. This was accompanied by significant increase in nitric oxide release and expression of antiendothelial nitric oxide synthase. This technique resulted in relatively pure arctiin extraction. Furthermore, the results from this study suggest that arctiin could potentially function as a protector against vascular endothelial cell injury and further investigation is warranted. 相似文献
72.
Abdel-Halim HI Imam SA Badr FM Natarajan AT Mullenders LH Boei JJ 《Cytogenetic and genome research》2004,104(1-4):193-199
Using fluorescence in situ hybridization with human band-specific DNA probes we examined the effect of ionizing radiation on the intra-nuclear localization of the heterochromatic region 9q12-->q13 and the euchromatic region 8p11.2 of similar sized chromosomes 9 and 8 respectively in confluent (G1) primary human fibroblasts. Microscopic analysis of the interphase nuclei revealed colocalization of the homologous heterochromatic regions from chromosome 9 in a proportion of cells directly after exposure to 4 Gy X-rays. The percentage of cells with paired chromosomes 9 gradually decreased to control levels during a period of one hour. No significant changes in localization were observed for chromosome 8. Using 2-D image analysis, radial and inter-homologue distances were measured for both chromosome bands. In unexposed cells, a random distribution of the chromosomes over the interphase nucleus was found. Directly after irradiation, the average inter-homologue distance decreased for chromosome 9 without alterations in radial distribution. The percentage of cells with inter-homologue distance <3 micro m increased from 11% in control cells to 25% in irradiated cells. In contrast, irradiation did not result in significant changes in the inter-homologue distance for chromosome 8. Colocalization of the heterochromatic regions of homologous chromosomes 9 was not observed in cells irradiated on ice. This observation, together with the time dependency of the colocalization, suggests an underlying active cellular process. The biological relevance of the observed homologous pairing remains unclear. It might be related to a homology dependent repair process of ionizing radiation induced DNA damage that is specific for heterochromatin. However, also other more general cellular responses to radiation-induced stress or change in chromatin organization might be responsible for the observed pairing of heterochromatic regions. 相似文献
73.
Abstract A protocol of protoplast isolation from Egyptian varieties of pea and bean is reported. Protoplast cultures were established from apical shoots of pea (Pisum sativum) and suspension cultures of bean (Phaseolus vulgaris). To isolate protoplasts of pea, apical shoot tissues were digested for 10 h using enzyme solution containing 1% pectinase, 0.5% cellulase, 0.5% hemicellulase, 10% mannitol and 0.1% CaCl2-2H2O. For protoplast isolation from suspension culture of bean, collected cells were incubated for 6 h in digestion solution containing 0.5% pectinase, 0.25% of each of cellulase and hemicellulase, 10% mannitol and 0.1% CaCl2-2H2O. Purified protoplasts were cultured in liquid culture medium. Microcalli were obtained after 30 days of culture. Calli colonies with a diameter of about 5 mm were developed after one month of culturing on solid B5 medium containing 2% sucrose, 2 g/l casein hydrolysate, 0.7% agar and supplemented with either 1 mg/l of each 2,4-D and kin in case of pea or 2 mg/l 2,4-D+0.5 mg/l kin in case of bean. Protoplast derived callus of pea was successfully differentiated into shoot and root, and highest frequency of shoot organogenesis was recorded on medium containing 0.5 mg/l NAA+2 mg/l BA. Protoplast derived callus of bean, on the other hand, gave rise to a high frequency of root formation when cultured on medium containing 1 mg/l NAA, but attempts to regenerate shoots from this callus was unsuccessfull. 相似文献
74.
Effect of ethyl alcohol on plasma testosterone level in mice 总被引:2,自引:0,他引:2
The effect of ethanol ingestion on testicular steroidogenesis in mice was evaluated by measuring plasma testosterone level. Four groups of CBA/J male mice were treated with one of the following doses of ethanol: 1.240, 0.620, 0.310 or 0.155 g ethanol/Kg body weight. A control group was given water. The data showed no effect of the treatment on testicular weight. The concentration of testosterone in the plasma was significantly reduced in animals treated with alcohol. There was also a significant relationship between the dose of alcohol and the plasma testosterone level, with the decrease in testosterone being from 2 to 18 fold in various groups. 相似文献
75.
Raoul R. Nigmatullin Sergey I. Osokin Dumitru Baleanu Sawsan Al-Amri Ameer Azam Adnan Memic 《PloS one》2014,9(4)
Over the past couple of decades there have been major advances in the field of nanoscience and nanotechnology. Many applications have sprouted from these fields of research. It is essential, given the scale of the materials, to attain accurate, valid and reproducible measurements. Material properties have shown to be a function of their size and composition. Physiochemical properties of the nanomaterials can significantly alter material behavior compared to bulk counterparts. For example, metal oxide nanoparticles have found broad applications ranging from photo-catalysis to antibacterial agents. In our study, we synthesized CuO nanoparticles using well established sol-gel based methods with varying levels of Ni doping. However, upon analysis of measured infrared data, we discovered the presence of quasi-periodic (QP) processes. Such processes have previously been reported to be tightly associated with measurement memory effects. We were able to detect the desired QP process in these measurements from three highly accurate repetitive experiments performed on each Ni (1–7%) doped CuO sample. In other words, successive measurements performed in a rather short period of time remember each other at least inside a group of neighboring measurements. 相似文献
76.
Ameer Y. Taha Hyung‐Wook Kim Lisa Chang Stanley I. Rapoport Yewon Cheon 《Journal of neurochemistry》2013,124(3):376-387
Chronic administration of mood stabilizers to rats down‐regulates the brain arachidonic acid (AA) cascade. This down‐regulation may explain their efficacy against bipolar disorder (BD), in which brain AA cascade markers are elevated. The atypical antipsychotics, olanzapine (OLZ) and clozapine (CLZ), also act against BD. When given to rats, both reduce brain cyclooxygenase activity and prostaglandin E2 concentration; OLZ also reduces rat plasma unesterified and esterified AA concentrations, and AA incorporation and turnover in brain phospholipid. To test whether CLZ produces similar changes, we used our in vivo fatty acid method in rats given 10 mg/kg/day i.p. CLZ, or vehicle, for 30 days; or 1 day after CLZ washout. [1‐14C]AA was infused intravenously for 5 min, arterial plasma was collected and high‐energy microwaved brain was analyzed. CLZ increased incorporation coefficients and rates Jin,i of plasma unesterified AA into brain phospholipids i, while decreasing plasma unesterified but not esterified AA. These effects disappeared after washout. Thus, CLZ and OLZ similarly down‐regulated kinetics and cyclooxygenase expression of the brain AA cascade, likely by reducing plasma unesterified AA availability. Atypical antipsychotics and mood stabilizers may be therapeutic in BD by down‐regulating, indirectly or directly respectively, the elevated brain AA cascade of that disease. 相似文献
77.
C. Mayasankaravalli K. Deepika D. Esther Lydia Reuben Agada Dluya Thagriki Chandramohan Govindasamy Veeramani Chinnadurai Othman Mohammed Othman Gatar Ameer Khusro Young Ock Kim Hak-Jae Kim 《Saudi Journal of Biological Sciences》2020,27(12):3228-3234
This context was investigated to assess the in vitro antioxidant, anti-diabetic, anti-obesity, and angiotensin-converting enzyme (ACE) inhibition traits of Punica granatum fruits peel extract. Initially, among various extracts tested, aqueous and ethanolic peel extracts depicted the presence of diverse phytoconstituents. In vitro antioxidative properties of peel extracts were determined using standard methodologies. Results showed that aqueous and ethanolic extracts had IC50 values of 471.7 and 509.16 μg/mL, respectively in terms of 1,1,diphenyl 2,2,picrylhydrazyl scavenging. Likewise, IC50 values of aqueous and ethanol extract were obtained as 488.76 and 478.47 μg/mL towards the degradation of hydrogen peroxide. The ethanolic extract exhibited the highest inhibition of α-glucosidase by showing activity of 53.34 ± 2.0 to 15.18 ± 1.4 U/L in a dose dependent manner (100–1000 µg/mL). Ethanolic extract was reported as the most active inhibitor of lipase with an IC50 value of 603.50 µg/mL. Ethanolic extract showed increased inhibition of ACE in a concentration dependent manner (100–1000 µg/mL) with IC50 value of 519.45 µg/mL. Fourier transform-infrared spectrum revealed the availability of various functional groups in the ethanolic extract of peel. Gas chromatography-mass spectrometry chromatogram of peel extract illustrated 23 diversified chemical constituents including 1,2,3,4-butanetetrol, Dimethyl sulfone, 9-octadecenamide, and Pentadecanoic acid as predominant compounds. In summary, P. granatum fruits peel extract revealed promising antioxidant, anti-diabetic, anti-obesity, and anti-hypertensive properties. 相似文献
78.
Satyvaldy Jatayev Igor Sukhikh Valeriya Vavilova Svetlana E. Smolenskaya Nikolay P. Goncharov Akhylbek Kurishbayev Lyudmila Zotova Aiman Absattarova Dauren Serikbay Yin-Gang Hu Nikolai Borisjuk Narendra K. Gupta Bertus Jacobs Stephan de Groot Francois Koekemoer Badr Alharthi Katso Lethola Dan T. Cu Carly Schramm Peter Anderson Colin L. D. Jenkins Kathleen L. Soole Yuri Shavrukov Peter Langridge 《Plant, cell & environment》2020,43(10):2355-2364
79.
Conventional photomixotrophic micropropagation systems are inefficient due to the high rates of mortality upon the transfer
of plantlets from in vitro to ex vitro conditions. Exogenous medium sugar has been suggested to be the major cause of this
problem. The aim of this study was to investigate the role of sucrose supply on the metabolic profile of in vitro-grown potato
plantlets subjected to different tissue culture conditions consisting of Murashige and Skoog medium and without sucrose [photoautotrophic
(PAT) condition] or with 3% sucrose [photomixotrophic (PMT) condition]. Using gas chromatography–mass spectrometry, we identified
a set of 51 different metabolites in leaf tissues during the rooting phase. Most growth parameters, such as shoot length,
leaf fresh weight, leaf number, and leaf area/plant, were significantly lower under PMT than under PAT conditions. Moreover,
photosynthesis was inhibited due to partial stomatal closure under PMT conditions. The metabolomic profiles along with principal
component analysis and hierarchical cluster analysis revealed that the two treatments were characterized by distinct metabolic
signatures. PAT leaves were characterized by the accumulation of urea and erythritol. In comparison, PMT leaves were characterized
by the accumulation of metabolites belonging to the primary metabolism and catecholamines as well as compounds related to
abiotic stress conditions, such as proline, hydroxyproline, asparagine, γ-aminobutyric acid (GABA), soluble sugars, and myo-inositol. 相似文献
80.