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991.
Mariana Costa Braga Schmidt Katia L.P. Morais Maíra Estanislau Soares de Almeida Asif Iqbal Mauricio Barbugiani Goldfeder 《Cell Adhesion & Migration》2020,14(1):129-138
ABSTRACT
In a tumor microenvironment, endothelial cell migration and angiogenesis allow cancer to spread to other organs causing metastasis. Indeed, a number of molecules that are involved in cytoskeleton re-organization and intracellular signaling have been investigated for their effects on tumor cell growth and metastasis. Alongside that, Amblyomin-X, a recombinant Kunitz-type protein, has been shown to reduce metastasis and tumor growth in in vivo experiments. In the present report, we provide a mechanistic insight to these antitumor effects, this is, Amblyomin-X modulates Rho-GTPases and uPAR signaling, and reduces the release of MMPs, leading to disruption of the actin cytoskeleton and decreased cell migration of tumor cell lines. Altogether, our data support a role for Amblyomin-X as a novel potential antitumor drug. 相似文献
992.
993.
Lucia Corso Anna Cavallero Debora Baroni Patrizia Garbati Gianfranco Prestipino Silvia Bisti Mario Nobile Cristiana Picco 《Purinergic signalling》2016,12(1):161-174
P2X7-type purinergic receptors are distributed throughout the nervous system where they contribute to physiological and pathological functions. In the retina, this receptor is found in both inner and outer cells including microglia modulating signaling and health of retinal cells. It is involved in retinal neurodegenerative disorders such as retinitis pigmentosa and age-related macular degeneration (AMD). Experimental studies demonstrated that saffron protects photoreceptors from light-induced damage preserving both retinal morphology and visual function and improves retinal flicker sensitivity in AMD patients. To evaluate a possible interaction between saffron and P2X7 receptors (P2X7Rs), different cellular models and experimental approaches were used. We found that saffron positively influences the viability of mouse primary retinal cells and photoreceptor-derived 661W cells exposed to ATP, and reduced the ATP-induced intracellular calcium increase in 661W cells. Similar results were obtained on HEK cells transfected with recombinant rat P2X7R but not on cells transfected with rat P2X2R. Finally, patch-clamp experiments showed that saffron inhibited cationic currents in HEK-P2X7R cells. These results point out a novel mechanism through which saffron may exert its protective role in neurodegeneration and support the idea that P2X7-mediated calcium signaling may be a crucial therapeutic target in the treatment of neurodegenerative diseases. 相似文献
994.
Rodrigo Fagundes Braga Vanesca Korasaki Lívia Dorneles Audino Julio Louzada 《Ecosystems》2012,15(7):1173-1181
We evaluated the effects of different land-use systems on the ability of dung beetles to control the population of detritus-feeding flies. We tested the hypotheses that intensification of land use will reduce dung beetles richness, abundance and biomass and, consequently, their dung burial ability, affecting the interaction between dung beetles and flies and reducing its effectiveness as a natural biological control. In the Brazilian Amazon we sampled dung beetles, fly larvae and adults; and recorded the rate of dung removal by dung beetles across a gradient of land-use intensity from primary forest, secondary forest, agroforestry, agriculture to pasture. Our results provide evidence that land-use intensification results in a reduction of the richness, abundance and biomass of dung beetles, and this in turn results in lower rates of dung removal in the most simplified systems. We found no significant differences in the abundance of fly larvae between the different systems of land use. However, the number of adult flies differed significantly between land-use systems, presenting higher abundance in those sites with greater intensity of use (pasture and agriculture) and a lower abundance of adult flies in forested systems (primary and secondary forests, and agroforestry). Information-theoretic model selection based on AICc revealed strong support for the influence of land-use systems, dung removal rates and dung beetle abundance, biomass and richness on adult dung-fly abundance. Our results also reveal that dung beetles are not solely responsible for fly control and that other factors linked to land use are influencing the populations of these detritus-feeding insects. 相似文献
995.
Lucia Y. Centeno-Betanzos Ricardo Reyes-Chilpa Natalia B. Pigni Christopher K. Jankowski Laura Torras-Claveria Jaume Bastida 《化学与生物多样性》2021,18(3):e2000834
The Libellus de Medicinalibus Indorum Herbis (Booklet of Indian Medicinal Plants) is the first book of medicinal plants written in the American continent. It was first published in 1939 as ‘An Aztec Herbal’. One of the depicted plants is Huetzcanixochitl (laughing flower) interpreted as Zephyranthes fosteri (Amaryllidaceae). No chemical or pharmacological studies are reported for this species; so, we decide to investigate it. The GC/MS of the bulbs and aerial parts extracts indicated that they contain Amaryllidaceae alkaloids, among them: lycorine, 3-O-acetylpowelline, and norlycoramine. An unknown major alkaloid was isolated and identified by 1H, 13C-NMR and MS, as 3′-demethoxy-6-epimesembranol ( 1 ). The methanolic extract, the alkaloid fraction, and compound 1 inhibited acetylcholinesterase in vitro. Mesembrine alkaloids are found in Sceletium species (Aizoaceae). Several are known as serotonin recapture inhibitors and have been proposed as potential antidepressant drugs. The presence of 1 suggests that Z. fosteri was probably used in pre-Columbian times in Mexico as a ‘stimulant and euphoriant’, alike Sceletium tortuosum by several ethnic groups in South Africa. 相似文献
996.
Cinzia Signorini Claudio De Felice Silvia Leoncini Rikke S. M?ller Gloria Zollo Sabrina Buoni Alessio Cortelazzo Roberto Guerranti Thierry Durand Lucia Ciccoli Maurizio D’Esposito Kirstine Ravn Joussef Hayek 《PloS one》2016,11(3)
Rett syndrome (RTT) and MECP2 duplication syndrome (MDS) are neurodevelopmental disorders caused by alterations in the methyl-CpG binding protein 2 (MECP2) gene expression. A relationship between MECP2 loss-of-function mutations and oxidative stress has been previously documented in RTT patients and murine models. To date, no data on oxidative stress have been reported for the MECP2 gain-of-function mutations in patients with MDS. In the present work, the pro-oxidant status and oxidative fatty acid damage in MDS was investigated (subjects n = 6) and compared to RTT (subjects n = 24) and healthy condition (subjects n = 12). Patients with MECP2 gain-of-function mutations showed increased oxidative stress marker levels (plasma non-protein bound iron, intraerythrocyte non-protein bound iron, F2-isoprostanes, and F4-neuroprostanes), as compared to healthy controls (P ≤ 0.05). Such increases were similar to those observed in RTT patients except for higher plasma F2-isoprostanes levels (P < 0.0196). Moreover, plasma levels of F2-isoprostanes were significantly correlated (P = 0.0098) with the size of the amplified region. The present work shows unique data in patients affected by MDS. For the first time MECP2 gain-of-function mutations are indicated to be linked to an oxidative damage and related clinical symptoms overlapping with those of MECP2 loss-of-function mutations. A finely tuned balance of MECP2 expression appears to be critical to oxidative stress homeostasis, thus shedding light on the relevance of the redox balance in the central nervous system integrity. 相似文献
997.
Raquel M. Braga Hermogenes F. Leitáo Filho Francisco De A.M. Reist 《Phytochemistry》1984,23(1):175-178
Fractionation of an ethereal extract of Peschiera fuchsiaefolia resulted in the isolation of decarbomethoxyvoacamine, demethylvoacamine, voacamidine, perivine, 16-epiaffinine and voacanginehydroxyindolenine, together with the previously reported alkaloids voacamine, voacangine, voachalotine and affinisine. Analysis of the 13C NMR spectra of the bisindole alkaloids and of 16-epiaffinine is reported. 相似文献
998.
999.
Martins João Paulo Rodrigues Vasconcelos Leandro Lopes de Braga Priscila da Conceição de Souza Rossini Franciele Pereira Conde Lorenzo Toscano Rodrigues Luiz Carlos de Almeida Falqueto Antelmo Ralph Gontijo Andreia Barcelos Passos Lima 《Plant Cell, Tissue and Organ Culture》2020,143(2):303-318
Plant Cell, Tissue and Organ Culture (PCTOC) - Copper (Cu) is an essential metal and both its deficiency and excess has negative effects on the growth and physiology of plants. Some plant species... 相似文献
1000.
Lóry Viktória Balážová Lucia Kršková Katarína Horváthová Ľubica Olszanecki Rafal Suski Maciej Zórad Štefan 《Journal of physiology and biochemistry》2019,75(3):351-365
Journal of Physiology and Biochemistry - There is a gap in the knowledge regarding regulation of local renin–angiotensin system (RAS) in skeletal muscle during development of obesity and... 相似文献