Browsing by Author "Perez, Claudia"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- ItemEstrategias didácticas que utilizan profesores de matemática de educación básica de centros urbanos y rurales(2014) Perez, Claudia; Solar Bezmalinovic, Horacio; Cid, Lorena
- ItemISOLATED LIGNANS OF ARAUCARIA ARAUCANA (MOLINA) K. KOCH PROVIDE WOOD PROTECTION AGAINST ATTACK BY THE XYLOPHAGOUS FUNGUS PLEUROTUS OSTREATUS (JACQ.) P. KUMM(2023) Bravo-Arrepol, Gaston; Torres, Solange; Perez, Claudia; Gonzalez-Ramirez, Mariela; Figueroa, Fabian; Cabrera-Barjas, Gustavo; Aranda, Mario; Tiezzi, Antonio; Gavin, Jose; Paz, Cristian; Becerra, JoseAraucaria araucana (Molina) K. Koch is an evergreen conifer endemic of Southern Chile and it is considered a sacred tree by the Pehuenche originary people. A. araucana is endangered in the red book. The knots wood of A. araucana are resistant to biological degradation, due to producing a high amount of lignans, even after the decomposition of the tree is possible to find its knots in the forest. In the present study the chemical composition of three wood tissue of A. araucana; knotwood, stemwood, and branches were analyzed by HPTLC-MS, GC-MS, and NMR. Three lignans were purified and identified as eudesmin (1), ((1S,2R,3R) 1,2,3,4tetrahydrona phthalene-2,3-diyl) dimethanol (2) and secoisolarisiresinol (3). Folin-Ciocalteu, DPPH and resistance to biodegradation assays were evaluated to extracts from compressed wood zones. Eudesmin was identified as the principal lignan in knots with a 0.5%w/w and outperformed the fungicide Nipacide (R) P511 in protecting wood against xylophage fungi Pleurotus ostreatus (Jacq.) P. Kumm.
- ItemShort bowel syndrome related intestinal failure outcomes in Latin America: Insights from the RESTORE Registry(2024) Rumbo, Carolina; Solar, Hector; Ortega, Mariana; Busoni, Veronica; de Barrio, Silvia; Martinuzzi, Andres; Martinez, Maria Ines; Plata, Clara; Donnadio, Luciana; Zuniga, Aurora Serralde; Saure, Carola; Perez, Claudia; Tanzi, Maria Noel; Consuelo, Alejandra; Becerra, Andres; Manzur, Alejandra; Moya, Diego Arenas; Rudi, Lorena; Moreira, Eduardo; Buncuga, Martin; Hodgson, Maria Isabel; Claria, Rodrigo Sanchez; Fernandez, Adriana; Gondolesi, GabrielBackgroundShort bowel syndrome is considered a low prevalence disease. The scant information available about intestinal failure in Latin America was the driving force to expand this registry.MethodsA prospective, multicenter observational registry was created for patients with chronic intestinal failure short bowel at specialized centers in Latin America. Demographics, clinical characteristics, nutrition assessment, parenteral nutrition management, intestinal rehabilitation, related complications, clinical outcome, and survival were analyzed.ResultsFrom May 2020 to July 2023, 167 patients (115 adults, 52 children) from 20 centers were enrolled. For the adults, the mean age was 37.2 +/- 18 years, 48% were female, and the mean follow-up was 22.6 +/- 18.3 months. The main etiology was surgical resections (postsurgical complications: 37%; ischemia: 25%); the mean intestinal length was 73 +/- 55 cm. The complications were as follows: infections: 0.4/1000 catheter-days; thrombosis: 0.24/1000 catheter-days; liver disease: 2.6%. The outcomes were as follows: 28% were rehabilitated, 15% died, 9.6% were lost to follow-up, 0.9% underwent transplant, and 45.6% continued follow-up. For the children, the mean age 48 +/- 52 months, 48% were female, 52% were premature. The mean follow-up was 17.2 +/- 5.6 months; the mean remaining intestinal length was 38 +/- 45 cm. The leading etiologies were atresia (25%), NEC (23%), and gastroschisis (21%). The complication were as follows: infections: 2/1000 catheter-days; thrombosis: 2.22/1000 catheter-day; 25% developed liver disease. The outcomes were as follows: 7.7% died, 3.8% were rehabilitated, and 88.5% continued follow-up.ConclusionThe RESTORE amendment served as a registry and educational tool for the participating teams. The aspiration is to objectively show current aspects of intestinal failure in the region and carry them to international standards. Including all Latin American countries and etiologies of chronic intestinal failure besides short gut would serve to complete this registry.
- ItemSulfated Polysaccharide Extracted from the Green Algae Codium bernabei: Physicochemical Characterization and Antioxidant, Anticoagulant and Antitumor Activity(2022) Figueroa, Fabian A.; Abdala-Diaz, Roberto T.; Perez, Claudia; Casas-Arrojo, Virginia; Nesic, Aleksandra; Tapia, Cecilia; Duran, Carla; Valdes, Oscar; Parra, Carolina; Bravo-Arrepol, Gaston; Soto, Luis; Becerra, Jose; Cabrera-Barjas, GustavoCodium bernabei is a green alga that grows on Chilean coasts. The composition of its structural polysaccharides is still unknown. Hence, the aim of this work is to isolate and characterize the hot water extracted polysaccharide fractions. For this purpose, the water extracts were further precipitated in alcohol (TPs) and acid media (APs), respectively. Both fractions were characterized using different physicochemical techniques such as GC-MS, GPC, FTIR, TGA, and SEM. It is confirmed that the extracted fractions are mainly made of sulfated galactan unit, with a degree of sulfation of 19.3% (TPs) and 17.4% (ATs) and a protein content of 3.5% in APs and 15.6% in TPs. Other neutral sugars such as xylose, glucose, galactose, fucose, mannose, and arabinose were found in a molar ratio (0.05:0.6:1.0:0.02:0.14:0.11) for TPs and (0.05:0.31:1.0:0.03:0.1:0.13) for ATs. The molecular weight of the polysaccharide samples was lower than 20 kDa. Both polysaccharides were thermally stable (Tonset > 190 degrees C) and showed antioxidant activity according to the ABTS(center dot+) and DPPH tests, where TPs fractions had higher scavenging activity (35%) compared to the APs fractions. The PT and APTTS assays were used to measure the anticoagulant activity of the polysaccharide fractions. In general, the PT activity of the TPs and APs was not different from normal plasma values. The exception was the TPs treatment at 1000 mu g mL(-1) concentration. The APTTS test revealed that clotting time for both polysaccharides was prolonged regarding normal values at 1000 mu g mL(-1). Finally, the antitumor test in colorectal carcinoma (HTC-116) cell line, breast cancer (MCF-7) and human leukemia (HL-60) cell lines showed the cytotoxic effect of TPs and APs. Those results suggest the potential biotechnological application of sulfate galactan polysaccharides isolated from a Chilean marine resource.