936 resultados para Davilla elliptica extract
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Background - Plants have proved to be an important source of anti-cancer drugs. Here we have investigated the cytotoxic action of an aqueous extract of Fagonia cretica, used widely as a herbal tea-based treatment for breast cancer. Methodology/Principal Findings - Using flow cytometric analysis of cells labeled with cyclin A, annexin V and propidium iodide, we describe a time and dose-dependent arrest of the cell cycle in G0/G1 phase of the cell cycle and apoptosis following extract treatment in MCF-7 (WT-p53) and MDA-MB-231 (mutant-p53) human breast cancer cell lines with a markedly reduced effect on primary human mammary epithelial cells. Analysis of p53 protein expression and of its downstream transcription targets, p21 and BAX, revealed a p53 associated growth arrest within 5 hours of extract treatment and apoptosis within 24 hours. DNA double strand breaks measured as ?-H2AX were detected early in both MCF-7 and MDA-MB-231 cells. However, loss of cell viability was only partly due to a p53-driven response; as MDA-MB-231 and p53-knockdown MCF-7 cells both underwent cell cycle arrest and death following extract treatment. p53-independent growth arrest and cytotoxicity following DNA damage has been previously ascribed to FOXO3a expression. Here, in MCF-7 and MDA-MB-231 cells, FOXO3a expression was increased significantly within 3 hours of extract treatment and FOXO3 siRNA reduced the extract-induced loss of cell viability in both cell lines. Conclusions/Significance - Our results demonstrate for the first time that an aqueous extract of Fagonia cretica can induce cell cycle arrest and apoptosis via p53-dependent and independent mechanisms, with activation of the DNA damage response. We also show that FOXO3a is required for activity in the absence of p53. Our findings indicate that Fagonia cretica aqueous extract contains potential anti-cancer agents acting either singly or in combination against breast cancer cell proliferation via DNA damage-induced FOXO3a and p53 expression.
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We present the first experimental implementation of an all-optical ROADM scheme for routing of individual channels within an all-optical OFDM superchannel. The interferometric technique demonstrated enables a fully flexible node, implementing the extraction, drop and addition of individual sub-channel.
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We present the experimental implementation of an all-optical ROADM scheme for routing of an individual subchannel within an all-optical OFDM superchannel. The different functions required of optical node were demonstrated using interferometric technique with the extraction, drop, and addition of individual subchannel in a ten subchannels optically aggregated signal. The scheme we reported enables a fully flexible node compatible with future terabit per second superchannel transmission.
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In Thailand, the leaves of Aquilaria crassna have been used traditionally for the treatments of various disorders, but without any scientific analysis. In this study, the antipyretic, analgesic, anti-inflammatory and anti-oxidative properties of A. crassna leaves extract were investigated at a wide dose range in rodents. Experimental animals were treated orally with an aqueous extract of Aquilaria crassna leaves (ACE). They were tested for antipyretic (Baker′s yeast-induced fever in rats), analgesic (hot plate test in mice) and anti-inflammatory (carrageenan-induced paw edema in rats) activities. An anti-oxidative effect of ACE was evaluated by using the DPPH anti-oxidant assay. The results showed that, after 5 hours of yeast injection, 400 and 800 mg/kg ACE significantly reduced the rectal temperature of rats. Mice were found significantly less sensitive to heat at an oral dose of 800 mg/kg ACE, after 60 and 90 min. No anti-inflammatory activity of ACE at an 800 mg/kg dose could be observed in the rat paw assay. An anti-oxidative activity of ACE was observed with an IC 50 value of 47.18 g/ ml. No behavioral or movement change could be observed in mice after oral administration of ACE (800 or 8,000 mg/kg) for seven consecutive days. Interestingly, from the second day of treatment, animals had a significant lower body weight at the 8,000 mg/kg dose of ACE compared to the control. No toxicity was identified and the results of this study state clearly that Aquilaria crassna leaves extracts possess antipyretic, analgesic and anti-oxidative properties without anti-inflammatory activity.
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A major drawback of artificial neural networks is their black-box character. Therefore, the rule extraction algorithm is becoming more and more important in explaining the extracted rules from the neural networks. In this paper, we use a method that can be used for symbolic knowledge extraction from neural networks, once they have been trained with desired function. The basis of this method is the weights of the neural network trained. This method allows knowledge extraction from neural networks with continuous inputs and output as well as rule extraction. An example of the application is showed. This example is based on the extraction of average load demand of a power plant.
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The experimental implementation of an all-optical node able of routing a channel contained in an all-optical OFDM super-channel is presented. The extract function is performed through channel selection, reshaping and interferometric suppression.
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EPA has been clinically shown to reduce muscle wasting during cancer cachexia. This study investigates whether curcumin or green tea extract (GTE) enhances the ability of low doses of eicosapentaenoic acid (EPA) to reduce loss of muscle protein in an in vitro model. A low dose of EPA with minimal anti-cachectic activity was chosen to evaluate any potential synergistic effect with curcumin or GTE. Depression of protein synthesis and increase in degradation was determined in C2C12 myotubes in response to tumour necrosis factor-α (TNF-α) and proteolysis-inducing factor (PIF). EPA (50 μM) or curcumin (10 μg ml−1) alone had little effect on protein degradation caused by PIF but the combination produced complete inhibition, as did the combination with GTE (10 μg ml−1). In response to TNF-α (25 ng ml−1)-induced protein degradation, EPA had a small, but not significant effect on protein degradation; however, when curcumin and GTE were combined with EPA, the effect was enhanced. EPA completely attenuated the depression of protein synthesis caused by TNF-α, but not that caused by PIF. The combination of EPA with curcumin produced a significant increase in protein synthesis to both agents. GTE alone or in combination with EPA had no effect on the depression of protein synthesis by TNF-α, but did significantly increase protein synthesis in PIF-treated cells. Both TNF-α and PIF significantly reduced myotube diameter from 17 to 13 μm for TNF-α (23.5%) and 15 μm (11.8%) for PIF However the triple combination of EPA, curcumin and GTE returned diameters to values not significantly different from the control. These results suggest that either curcumin or GTE or the combination could enhance the anti-catabolic effect of EPA on lean body mass.
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Quorum sensing (QS) is the phenomenon by which microorganisms regulate gene expression in response to cell-population density. These microorganisms synthesize and secrete small molecules known as autoinducers that increase in concentration as a function of cell density. Once the cell detects the minimal threshold concentration of an autoinducer, the gene expression is altered accordingly. Although the cellular circuitry responding to QS is relatively conserved, the cellular processes regulated by QS, for example are conjugation, motility, sporulation, biofilm formation and production of virulence factors importamt for infection. Since many pathogens have developed resistance to available antibiotics, novel therapies are required to further treat these pathogens. Inhibitors of QS are potential therapeutic candidates since they would inhibit virulence without selecting for antibiotic resistant strains. Previous studies have shown that the Chinese herb Panax ginseng contains compounds that inhibit QS activity. To further characterize this activity, a highly sensitive quantitative liquid assay was developed using a Chromobacterium violaceum AHL mutant, CV026 as a biomonitor strain. After confirmation that P. ginseng aqueous extracts had anti-QS activity, the extract was fractionated on a reverse phase C18 Sep Pak column. Most anti-QS activity was present in the flow through, and compounds eluted with ten percent acetonitrile in water antibacterial activity. We thus conclude that P. ginseng has anti-QS activity and the active compound is water soluble. Compounds from P. ginseng, could be used as a lead structure to design compound with higher anti-QS activity for therapeutic treatments.
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Elevated temperatures associated with ocean warming and acidification can influence development and, ultimately, success of larval molluscs. The effect of projected oceanic changes on fertilisation and larval development in an Antarctic bivalve, Laternula elliptica, was investigated through successive larval stages at ambient temperature and pH conditions (-1.6°C and pH 7.98) and conditions representative of projections through to 2100 (-0.5°C to +0.4°C and pH 7.80 to pH 7.65). Where significant effects were detected, increased temperature had a consistently positive influence on larval development, regardless of pH level, while effects of reduced pH varied with larval stage and incubation temperature. Fertilisation was high and largely independent of stressors, with no loss of gamete viability. Mortality was unaffected at all development stages under experimental conditions. Elevated temperatures reduced occurrences of abnormalities in D-larvae and accelerated larval development through late veliger and D-larval stages, with D-larvae occurring 5 d sooner at 0.4°C compared to ambient temperature. Reduced pH did not affect occurrences of abnormalities in larvae, but it slowed the development of calcifying stages. More work is required to investigate the effects of developmental delays of the magnitude seen here in order to better determine the ecological relevance of these changes on longer term larval and juvenile success.
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A high input of lithogenic sediment from glaciers was assumed to be responsible for high Fe and Mn contents in the Antarctic soft shell clam Laternula elliptica at King George Island. Indeed, withdrawal experiments indicated a strong influence of environmental Fe concentrations on Fe contents in bivalve hemolymph, but no significant differences in hemolymph and tissue concentrations were found among two sites of high and lower input of lithogenic debris. Comparing Fe and Mn concentrations of porewater, bottom water, and hemolymph from sampling sites, Mn appears to be assimilated as dissolved species, whereas Fe apparently precipitates as ferrihydrite within the oxic sediment or bottom water layer prior to assimilation by the bivalve. Hence, we attribute the high variability of Fe and Mn accumulation in tissues of L. elliptica around Antarctica to differences in the geochemical environment of the sediment and the resulting Fe and Mn flux across the benthic boundary.
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Recent rapid changes of air temperature on the western side of the Antarctic Peninsula results in increased sediment discharge and ice scouring frequencies in coastal regions. These changes are bound to especially affect slow growing, sessile filter feeders such as the Antarctic bivalve, Laternula elliptica, a long-lived and abundant key species with circumpolar distribution. We investigated the effect of sedimentation and ice scouring on small/young and large/old individuals at two closely located stations, distinctly influenced by both types of disturbance. Small individuals dealt better with disturbance in terms of their respiratory response to sediment exposure, reburrowing ability, and survival after injury, compared to larger animals. At the more disturbed station L. elliptica population density was lower, but larger animals reburrowed faster after iceberg disturbance and reduced their metabolic rate under strong sediment coverage, compared to larger animals of the less disturbed station, indicating that an adaptation or learning response to both types of disturbance may be possible. Smaller individuals were not influenced. Laternula elliptica seems capable of coping with the rapidly changing environmental conditions. Due to a decrease in population density and mean population lifespan, L. elliptica could however lose its key role in the bentho-pelagic carbon flux in areas of high sediment deposition.
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We would like to dedicate this article to the memory of Professor Yoram Milner, who has passed away before this study was achieved. We are immeasurably indebted to him, professionally and personally. The study was supported by grants from the ICA Foundation and the Ministry of Science, Technology and Space.
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Atlantic killifish (Fundulus heteroclitus) inhabiting the Atlantic Wood Industries region of the Elizabeth River, Virginia, have passed polycyclic aromatic hydrocarbon (PAH) resistance to their offspring as evidenced by early life stage testing of developmental toxicity after exposure to specific PAHs. Our study focused on environmentally relevant PAH mixtures in the form of Elizabeth River sediment extract (ERSE). Juvenile (5 month) F1 progeny of pollution-adapted Atlantic Wood (AW) parents and of reference site (King's Creek [KC]) parents were exposed as embryos to ERSE. Liver alterations, including nonneoplastic lesions and microvesicular vacuolation, were observed in both populations. ERSE-exposed KC fish developed significantly more alterations than unexposed KC fish. Interestingly, unexposed AW killifish developed significantly more alterations than unexposed KC individuals, suggesting that AW juveniles are not fully protected from liver disease; rapid growth of juvenile fish may also be an accelerating factor for tumorigenesis. Because recent reports show hepatic tumor formation in adult AW fish, the differing responses from the 2 populations provided a way to determine whether embryo toxicity protection extends to juveniles. Future investigations will analyze older life stages of killifish to determine differences in responses related to chronic disease.