Browsing by Author "Ramirez, Carolina"

Now showing 1 - 4 of 4
  • No Thumbnail Available
    Item
    An Improved Protocol to Purify and Directly Mono-Biotinylate Recombinant BDNF in a Tube for Cellular Trafficking Studies in Neurons
    (2020) Stuardo, Nicolas; Moya-Alvarado, Guillermo; Ramirez, Carolina; Schiavo, Giampietro; Bronfman, Francisca C.
    Recombinant BDNF containing an Avi sequence (BDNFAvi) is produced in HEK293 cells and then cost-effectively purified by affinity chromatography. A reproducible protocol was developed to directly mono-biotinylate BDNFAvi with the enzyme BirA in a tube. In this reaction, mono-biotinylated BDNFAvi retains its biological activity.
  • Thumbnail Image
    Item
    Coagulation Factor Xa Promotes Solid Tumor Growth, Experimental Metastasis and Endothelial Cell Activation.
    (2019) Arce, Maximiliano; Pinto, Mauricio P.; Galleguillos, Macarena; Muñoz, Catalina; Lange, Soledad; Ramirez, Carolina; Erices, Rafaela; Gonzalez, Pamela; Velasquez, Ethel; Tempio, Fabián; Lopez, Mercedes N.; Salazar-Onfray, Flavio; Cautivo, Kelly; Kalergis, Alexis M.; Cruz, Sebastián; Lladser, Álvaro; Lobos-González, Lorena; Valenzuela, Guillermo; Olivares, Nixa; Sáez, Claudia; Koning, Tania; Sánchez, Fabiola A.; Fuenzalida, Patricia; Godoy, Alejandro; Contreras Orellana, Pamela; Leyton, Lisette; Lugano, Roberta; Dimberg, Anna; Quest, Andrew F.G.; Owen, Gareth I.
    Hypercoagulable state is linked to cancer progression; however, the precise role of the coagulation cascade is poorly described. Herein, we examined the contribution of a hypercoagulative state through the administration of intravenous Coagulation Factor Xa (FXa), on the growth of solid human tumors and the experimental metastasis of the B16F10 melanoma in mouse models. FXa increased solid tumor volume and lung, liver, kidney and lymph node metastasis of tail-vein injected B16F10 cells. Concentrating on the metastasis model, upon coadministration of the anticoagulant Dalteparin, lung metastasis was significantly reduced, and no metastasis was observed in other organs. FXa did not directly alter proliferation, migration or invasion of cancer cells in vitro. Alternatively, FXa upon endothelial cells promoted cytoskeleton contraction, disrupted membrane VE-Cadherin pattern, heightened endothelial-hyperpermeability, increased inflammatory adhesion molecules and enhanced B16F10 adhesion under flow conditions. Microarray analysis of endothelial cells treated with FXa demonstrated elevated expression of inflammatory transcripts. Accordingly, FXa treatment increased immune cell infiltration in mouse lungs, an effect reduced by dalteparin. Taken together, our results suggest that FXa increases B16F10 metastasis via endothelial cell activation and enhanced cancer cell-endothelium adhesion advocating that the coagulation system is not merely a bystander in the process of cancer metastasis.
  • Thumbnail Image
    Item
    Effects of Japanese herbal medicine inchin-ko-to on endotoxin-induced cholestasis in the rat
    (MEXICAN ASSOC HEPATOLOGY, 2009) Pablo Arab, Juan; Ramirez, Carolina; Munoz, Pablo; Pizarro, Margarita; Solis, Nancy; Riquelme, Arnoldo; Arrese, Marco
    Background/Objective. Inchin-ko-to (ICKT) is an herbal medicine used in Japan to treat jaundice and liver fibrosis. We investigated the effect of oral ICKT supplementation on endotoxin-induced cholestasis in the rat. Material and methods. Lipopolysaccharide (LPS) injection (1 mg/kg body weight i.p.) was used as a model of sepsis-induced cholestasis. Bite flow, biliary bile salt secretion, biliary glutathione secretion and protein expression of the main hepatobiliary transporters Na(+)-taurocholate-cotransporting peptide (Ntcp), multidrug resistance protein 2 (Mrp2) and bile salt export pump (Bsep) were analyzed by conventional techniques in ICKT treated and non-treated animals. Results. Injection of LIDS induced a significant decrease of bite ftow (-24%), biliary bite salts (-40%) and glutathione excretion (-70%) as well as a significant decrease in Ntcp (-90%) and Mrp2 (-80%) protein levels. ICKT supplementation partially prevented the effects of LIPS determining a less intense reduction in bile flow (-10%), a normalization of glutathione excretion as well as a significant increase in Mrp2 protein levels to 60% of the levels observed in control animals. ICKT administration did not modify the effects of LPS on BS secretion or Ntcp protein levels. Conclusion. Our data show that oral. supplementation of ICKT partially prevents LPS-induced cholestasis by increasing Mrp2 protein levels and biliary glutathione excretion thus increasing bite salt-independent ftow.
  • No Thumbnail Available
    Item
    Representations of migration during the sociosanitary crisis: A lexicometric analysis of Chilean digital media
    (2023) Figueiredo, Ana; Ramirez, Carolina; Ivanova, Anna; Montagna-Letelier, Pietro
    This manuscript analyzes the representations of migration in digital news media, during the first six months of the COVID-19 pandemic in Chile. In total, 311 news from three digital news outlets were analyzed, which differed in their editorial frames and were among the most visited in Chi-le: El Mostrador, Cooperativa and EMOL. A mixed study (quantitative and qualitative) was carried out, through a lexicometric analysis, which allows analyzing large corpus of data. The findings indi-cate the existence of six vocabulary classes (clus-ters), which illustrate different ways in which the migratory phenomenon was represented during the COVID-19 pandemic. Our main results are dis-cussed regarding the content in each clustter and linked to previous national and international stu-dies. Beyond the pandemic, the findings invite to expand our understanding of migration represen-tation in contexts of crisis.