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Made available in DSpace on 2022-04-29T08:46:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-04-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The combined application of chitosan (CS) and liquid smoke (LS) leads to the development of a suitable material with synergistic properties and promising potential for use as an efficient preservative for the conservation of food products. The present work investigates the development and characterization of liquid smoke-loaded chitosan nanoparticles (LS-CS/NPs) with the optimization of the preparation conditions using response surface methodology and the analysis of the antioxidant and antibacterial properties of the nanoparticles as well as the controlled release of the liquid smoke. The nanoparticles were prepared by the ionic gelation method and were characterized by DLS, zeta potential, FT-IR, SEM, and EDS. The analysis of antioxidant activity of LS-CS/NPs was performed by the free radicals scavenging method (DPPH and ABTS) while the study of the total phenolic content of the particles was conducted via the application of the Folin-Ciocalteau method with some modifications. The analysis of antimicrobial activity of the LS-CS/NPs was performed using the minimum inhibitory concentration method involving the growth of Gram-positive (S. aureus and B. cereus) and Gram-negative (E. coli and Salmonella spp) bacteria. The analysis of the controlled release of liquid smoke was conducted at 4 °C using the Korsmeyer-Peppas model. The results obtained showed that the nanoparticles prepared using CS and LS in the ratio 1.5: 0.583, respectively (F′2), which had an average size of 205 nm and zeta potential of 45 mV, exhibited good antioxidant (%DPPH: 92.7% and %ABTS: 93%) and antibacterial activities, with an efficient, gradual controlled release of liquid smoke (release rate = 0.042 min−1). Food Research Group Chemical Engineering - National University of Engineering (GIA-FIQT-UNI), Av. Tupac Amaru 210, Rimac Department of Food and Agricultural Products Engineering Faculty of Food Industries National Agrarian University, Av. La Molina s/n, La Molina Faculty of Pharmacy and Biochemistry Universidad Nacional Mayor de San Marcos, Av. Universitaria s/n Faculty of Sciences National University of Engineering, Av. Tupac Amaru 210, Rimac Grupo de Investigación Materiales para la Innovación Tecnológica de la Facultad de Química e Ingeniería Química Universidad Nacional Mayor de San Marcos, Calle Germán Amézaga 375 Laboratorio de Investigación en Biopolímeros y Metalofármacos (LIBIPMET) National University of Engineering, Av. Tupac Amaru 210, Rimac Institute of Chemistry UNESP-São Paulo State University National Institute for Alternative Technologies of Detection Toxicological Evaluation & Removal of Micropollutants and Radioactives (INCT-DATREM) Institute of Chemistry UNESP-São Paulo State University FAPESP: 2014/50945-4 CNPq: 465571/2014–0

Introduction Ductal carcinoma in situ (DCIS) accounts for 15% of breast cancers. Surgery is the main treatment, and the use of sentinel node biopsy (SLNB) is restricted to patients at risk of infiltration, which is estimated to be around 26%. Materials and methods Aimed at evaluating the benefit of SLNB in patients with DCIS at the Breast and Soft Tissue Functional Unit of the National Cancer Institute (INC for its initials in Spanish), a descriptive observational study of a retrospective cases series was conducted between August 1, 2013, and September 30, 2018. Results A total of 40 patients with a median age of 57 years were included in the study; 62.5% of them underwent mastectomy with SLNB, and the remaining 37.5% underwent conservative surgery with SLNB. 100% of sentinel nodes were identified, by using lymphoscintigraphy in 95%. Sentinel node was positive in four patients (10%), three of whom had infiltration in the surgical specimen reported. With a follow-up of 49 months, only one patient had a local relapse. None of the patients had axillary or distant recurrence. Conclusions SLNB in DCIS should be limited to patients with risk factors for infiltration (tumor size greater than 3 cm, comedo-type histology, and high-grade DCIS), and patients with an indication for mastectomy. Its percentage of complications is low, and a high identification percentage in surgical groups with adequate training.

This paper addresses the path followed by two private higher education institutions (HEI) in Colombia towards achieving carbon neutrality. The methodology followed by these universities to achieve a carbon-neutral certification, based on the Greenhouse Gas (GHG) Protocol, is first described. The process of developing the GHG inventory, projected towards the carbon neutrality of these organisations while using the standard ISO 14064:2006, involved a series of steps that were consolidated in three phases: (i) definition of the scope, collection of data and emissions quantification; (ii) analysis of results and mitigation actions; and (iii) verification and compensation strategies. Results for the HEIs are shown in terms of the organisational context, carbon footprint measurement, reduction, verification, and compensation. The case is presented for Universidad Pontificia Bolivariana, a multi-campus university that became the first carbon-neutral university in Latin America in 2017, and Universidad Ean, a single-campus university that became the second carbon-neutral university in Colombia in 2021, as verified by the Colombian Institute of Technical Standards and Certification (ICONTEC). This work shows that universities can play a key role in regional and global agendas with their contribution through the incorporation of sustainability strategies, since HEIs can not only achieve carbon neutrality, but they can help other organisations by delivering graduates who are aware of sustainability and provide specific training towards building a sustainability culture, which is needed for regenerative development.

Introduction Breast sarcomas are tumors of a mesenchymal origin, with an incidence of less than 1% of the total breast tumors. The diagnosis of this disease is a challenge for pathologists, radiologists, and breast surgeons. Aim To describe the diagnostic, therapeutic, and outcomes approach of patients with breast sarcoma treated at the National Cancer Institute (NCI) in Bogota, Colombia. Materials and methods It is a descriptive and retrospective case series study of patients diagnosed with breast sarcoma treated at the NCI during the period between August 1, 2016 and March 30, 2019. Results We identified 14 patients diagnosed with breast sarcoma, 10 (71.4%) patients with primary breast sarcomas, and four (28.6%) with sarcomas associated with radiotherapy. The most frequent histological subtype in both, primary and secondary sarcomas, was angiosarcoma (n = 5, 35.7%). 100% (n = 14) of patients received surgical management as primary treatment. Eight (57.1%) patients presented recurrence (disease-free survival (DFS) follow-up of 5.95 months). A total of five deaths were recorded, representing 35.7% of patients (overall survival (OS) follow-up of 23.5 months). Conclusion Breast sarcomas are characterized by aggressive clinical behavior, which is why it is important to make a precise histological diagnosis and thus provide patients with radical surgical procedures that ensure local control of the disease and improve DFS.

In this work we present the results about the preparation of the superconductor YBa2Cu3O7-δ (Y123) by sol-gel method using oxalate precursors. Samples were prepared by dissolving stoichiometric mixtures of Y(OOCCH3).4H2O, Ba(OOCCH3)2 and Cu(OOCCH3)2.H2O acetates in aqueous solution of oxalic acid, HCOO-COOH. The particulate sols obtained (2g.) were divided in two parts (1g. each one), from which the first one (sample A) was grinded, pellet, calcined (860°C) and sinterised at 860°C in oxidizing atmosphere, the second part (sample B) was grinded, pellet, calcined at 880°C and finally sinterized at 880°C in the same conditions, the XRD revels the superconductor Y123 is formed in the first sample, but coexisting with remarkable presence of the secondary phases: CuO, BaCu3O4, BaCO3 and BaCuO2, while in sample B the XRD reveals the obtention of high purity monophase Y123, the ac susceptibility measurement using a Quantum Design (SQUID) magnetometer indicates TC(onset)=92K for this sample, moreover the Rietveld refinement was done taking the orthorhombic Pmmm Y123 spatial group as a model, this suggest the cell´s parameters a=3.839Å, b=3.899 Å and c=11.702Å as reported in the literature. Therefore for the preparation of Y123-superconductor using oxalate precursors, the optimus sintering temperature is 880°C.