2,813 research outputs found
New Advances in Environmental Friendly Materials
This last decade has been characterized by the acquisition ofnew materials based on the biomass, with the objective of replacingthe materials obtained from petroleum derivatives, due to the highcosts, added to the fact that they are non-renewable inputs and as ameasure of the preservation of the environment [1]. In all areas ofstudy has been this responsibility of searching for new and versatilematerials. Packaging, medical materials, agro-industry, cosmetics,even energy applications, in all these fields are in constant search tobe at the forefront and at the same time reduce all those materialsthat, during and at the end of their life cycle, cause damage to theenvironment, either due to the emission of greenhouse gases, orbecause they lack biodegradable and / or compostable propertiesFil: Garcia, Nancy Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Rodriguez Ramirez, Carlos Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: D'accorso, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; Argentin
Switchable CAR T cell strategy against osteosarcoma
Immunotherapy with chimeric antigen receptor T (CAR T) cells has changed the treatment of hematological malignances, but they are still a challenge for solid tumors, including pediatric sarcomas. Here, we report a switchable CAR T cell strategy based on anti-FITC CAR T cells and a switch molecule conjugated with FITC for targeting osteosarcoma (OS) tumors. As a potential target, we analyzed the expression of B7-H3, an immune checkpoint inhibitor, in OS cell lines. In addition, we evaluate the capacity of an anti-B7-H3 monoclonal antibody conjugated with FITC (anti-B7-H3-FITC mAb) to control the antitumor activity of anti-FITC CAR T cells. The effector functions of anti-FITC CAR T cells against OS, measured in vitro by tumor cell killing activity and cytokine production, are dependent on the presence of the anti-B7-H3-FITC mAb switch. Moreover, OS cells stimulate anti-FITC CAR T cells migration. In vivo, anti-B7-H3 mAb penetrates in the tumor and binds 143B OS tumor cells. Furthermore, anti-FITC CAR T cells reach tumor region and exert antitumor effect in an OS NSG mouse model only in the presence of the switch molecule. We demonstrate that anti-B7-H3-FITC mAb redirects the cytotoxic activity of anti-FITC CAR T cells against OS tumors suggesting that switchable CAR T cell platforms might be a plausible strategy against OS.This research was funded by Instituto de Salud Carlos III (ISCIII): PI20CIII-00040 and RD21/0017/0005, Red Española de Terapias Avanzadas TERAV-ISCIII (NextGenerationEU. Plan de Recuperación Transformación y Resiliencia), the Asociación Pablo Ugarte, the Fundación Oncohematología Infantil and AFANION for grants support. LH is benefciary of a grant under the Talent Attraction Program of the Comunidad de Madrid (2018-T2/BMD-10337). AM-M is benefciary of a grant under the PhD ISCIII-PFIS program (FI18CIII/00017) and is a member of the PhD Program in Molecular Biosciences of Universidad Autónoma de Madrid. PR-G is enrolled in the Doctoral Program in Biomedical Sciences and Public Health as a trainee researcher at the UNED International Doctoral School. AntiFITC CAR single chain variable fragment (scFv) encoding plasmid was kindly provided by Dr. Michael Jensen from Seattle Children´s Research Institute, Washington, USA. The authors wish to thank the donors, and the Biobank Hospital Universitario Puerta de Hierro Majadahonda (HUPHM)/Instituto de Investigación Sanitaria Puerta de Hierro-Segovia de Arana (IDIPHISA) (PT17/0015/0020 in the Spanish National Biobanks Network) for the human specimens used in this study. Images for the graphical scheme of experiments were obtained and modifed from SMART—Servier Medical Art under a Creative Common Attribution 3.0 Unported License.S
Stand types discrimination comparing machine-learning algorithms in Monteverde, Canary Islands.
Aim of study: The main objective is to determine the best machine-learning algorithm to classify the stand types of Monteverde forests combining LiDAR, orthophotography, and Sentinel-2 data, thus providing an easy and cheap method to classify Monteverde stand types.Area of study: 1500 ha forest in Monteverde, North Tenerife, Canary Islands.Material and methods: RF, SVML, SVMR and ANN algorithms are used to classify the three Monteverde stand types. Before training the model, feature selection of LiDAR, orthophotography, and Sentinel-2 data through VSURF was carried out. Comparison of its accuracy was performed.Main results: Five LiDAR variables were found to be the most efficient for classifying each object, while only one Sentinel-2 index and one Sentinel-2 band was valuable. Additionally, standard deviation and mean of the Red orthophotography colour band, and ratio between Red and Green bands were also found to be suitable. SVML is confirmed as the most accurate algorithm (0.904, 0.041 SD) while ANN showed the lowest value of 0.891 (0.073 SD). SVMR and RF obtain 0.902 (0.060 SD) and 0.904 (0.056 SD) respectively. SVML was found to be the best method given its low standard deviation.Research highlights: The similar high accuracy values among models confirm the importance of taking into account diverse machine-learning methods for stand types classification purposes and different explanatory variables. Although differences between errors may not seem relevant at a first glance, due to the limited size of the study area with only three plus two categories, such differences could be highly important when working at large scales with more stand types.ADDITIONAL KEY WORDSRF algorithm, SVML algorithm, SVMR algorithm, ANN algorithm, LiDAR, orthophotography, Sentinel-2ABBREVIATIONS USEDANN, artificial neural networks algorithm; Band04, Sentinel-2 band 04 image data; BR, brezal; DTHM, digital tree height model; DTHM-2016, digital tree height model based on 2016 LiDAR data; DTM, digital terrain model; DTM-2016, digital terrain model based on 2016 LiDAR data; FBA, fayal-brezal-acebiñal; FCC, canopy cover; HEIGHT-2009, maximum height based on 2009 LiDAR data; HGR, height growth based on 2009 and 2016 LiDAR data; LA, laurisilva; NDVI705, Sentinel-2 index image data; NMF, non-Monteverde forest; NMG, non-Monteverde ground; P95-2016, height percentile 95 based on 2016 LiDAR data; RATIO R/G, ratio between Red and Green bands orthophotograph data; RED, Red band orthophotograph data; Red-SD, standard deviation of the Red band orthophotograph data; RF, random forest algorithm; SVM, support vector machine algorithm; SVML, linear support vector machine algorithm; SVMR, radial support vector machine algorithm; VSURF, variable selection using random forest.
Tailoring the Properties of Thermo-Compressed Polylactide Films for Food Packaging Applications by Individual and Combined Additions of Lactic Acid Oligomer and Halloysite Nanotubes
[EN] In this work, films of polylactide (PLA) prepared by extrusion and thermo-compression were plasticized with oligomer of lactic acid (OLA) at contents of 5, 10, and 20 wt%. The PLA sample containing 20 wt% of OLA was also reinforced with 3, 6, and 9 parts per hundred resin (phr) of halloysite nanotubes (HNTs) to increase the mechanical strength and thermal stability of the films. Prior to melt mixing, ultrasound-assisted dispersion of the nanoclays in OLA was carried out at 100 ºC to promote the HNTs dispersion in PLA and the resultant films were characterized with the aim to ascertain their potential in food packaging. It was observed that either the individual addition of OLA or combined with 3 phr of HNTs did not significantly affect the optical properties of the PLA films, whereas higher nanoclay contents reduced lightness and induced certain green and blue tonalities. The addition of 20 wt% of OLA increased ductility of the PLA film by nearly 75% and also decreased the glass transition temperature (Tg) by over 18 ºC. The incorporation of 3 phr of HNTs into the OLA-containing PLA films delayed thermal degradation by 7 ºC and additionally reduced the permeabilities to water and limonene vapors by approximately 8% and 47%, respectively. Interestingly, the highest barrier performance was attained for the unfilled PLA film plasticized with 10 wt% of OLA, which was attributed to a crystallinity increase and an effect of ¿antiplasticization¿. However, loadings of 6 and 9 phr of HNTs resulted in the formation of small aggregates that impaired the performance of the blend films. The here-attained results demonstrates that the properties of ternary systems of PLA/OLA/HNTs can be tuned when the plasticizer and nanofiller contents are carefully chosen and the resultant nanocomposite films can be proposed as a bio-sourced alternative for compostable packaging applications.This research work was funded by the Spanish Ministry of Science and Innovation (MICI) project numbers RTI2018-097249-B-C21 and MAT2017-84909-C2-2-R. S.R.-L is a recipient of a Santiago Grisolia grant from Generalitat Valenciana (GVA)
(GRISOLIAP/2019/132). L.Q.-C. wants to thank GVA for his FPI grant (ACIF/2016/182) and the Spanish Ministry of Education, Culture, and Sports (MECD) for his FPU grant (FPU15/03812), while D.G.-G. also acknowledges GVA for his postdoctoral contract (APOSTD/2019/201). B.M.-R. and S.T.-G. acknowledge MICIU for her FPI grant (BES-2016-077972) and his Juan de la Cierva¿Incorporación contract (IJCI-2016-29675), respectively.Rojas-Lema, S.; Quiles-Carrillo, L.; Garcia-Garcia, D.; Melendez-Rodriguez, B.; Balart, R.; Torres-Giner, S. (2020). Tailoring the Properties of Thermo-Compressed Polylactide Films for Food Packaging Applications by Individual and Combined Additions of Lactic Acid Oligomer and Halloysite Nanotubes. Molecules. 25(8). https://doi.org/10.3390/molecules2508197625
Assessment of deep eutectic solvents (DES) to fractionate Paulownia wood within a biorefinery scheme: Cellulosic bioethanol production and lignin isolation
Five deep eutectic solvents (DES) were evaluated to disrupt Paulownia wood structure to produce bioethanol and lignin. The DES formulated with choline chloride:lactic acid provided the most promising result. Temperature (110–130 ◦C), residence time (30–120 min), molar ratio (1:2–1:9), and liquid-to-solid ratio (8–15 mL/g) were optimized for cellulose recuperation (93% retained in the solid phase) and lignin removal (94% delignification yield). The spent solid was used for bioethanol production, achieving up to 43.6 g ethanol/L (89.7% ethanol yield). Lignin (84% of purity) was isolated from the black liquor and thoroughly characterized by FTIR, 1H NMR, TGA-DTG and SEM, while the liquor after lignin precipitation was chemically characterized for monomers/oligomers, total phenolic content, antioxidant activity and phytochemical profile (highlighting the presence of 25.06, 10.21 and 2.51 mg of syringaldehyde, vanillin and 3,4-dihydroxibenzoic acid per g of initial biomass). Overall, this study show that DES pre-treatment is a promising strategy for simultaneous lignin extraction and cellulose digestibility enhancement.Interreg | Ref. S1/1.1/ E0116Xunta de Galicia | Ref. ED431C 2021/46-GRCXunta de Galicia | Ref. ED481B-2022–020Agencia Estatal de Investigación | Ref. PID2019–110031RB-I00Ministerio de Universidades | Ref. FPU20/02385Universidade de Vigo/CISUGAgencia Estatal de Investigación | Ref. RYC2018–026177-
Exploring the ring-closing metathesis for the construction of the solomonamide macrocyclic core: identification of bioactive precursors
New synthetic strategies directed toward the novel cyclopeptides solomonamides have been explored utilizing an olefin metathesis as the key reaction. In the various strategies investigated, we worked on minimally oxidized systems, and the olefin metathesis reaction demonstrated efficiency and validity for the construction of the macrocyclic core. The described synthetic strategies toward the solomonamides are well suited for the subsequent access to the natural products and represent flexible and diversityoriented routes that allow for the generation of a variety of analogues via oxidative transformations. In addition, preliminary biological evaluations of the generated solomonamide precursors revealed antitumor activity against various tumor cell lines.This work was financially supported by the Ministerio de Economía y Competitividad (MINECO) (ref BIO2014-56092-R, CTQ2014-60223-R and CTQ2016-76311-R) and Junta de Andalucía and “Fondo Europeo de Desarrollo Regional-FEDER” (P12
CTS-1507). I.C.-S. thanks Ministerio de Educación, Cultura y Deporte for a predoctoral fellowship (FPU programme)
Microwave-assisted extraction of hemicellulosic oligosaccharides and phenolics from Robinia pseudoacacia wood
Financiaciado para publicación en acceso aberto: Universidade de Vigo/CISUGMicrowave-assisted autohydrolysis is an environmentally friendly intensification technology that permits the selective solubilization of hemicelluloses in form of oligosaccharides in a short time and with low energy consumption. The purpose of this work was to evaluate the suitability of microwave-assisted autohydrolysis to produce oligosaccharides and phenolics with potential prebiotic and antioxidant activities from Robinia pseudoacacia wood. The influence of treatment time (0–30 min) and temperature (200–230 ◦C) on oligosaccharide production was studied and conditions of 230 ◦C and 0.25 min resulted in maximum content of xylooligosaccharides (7.69 g XO/L) and more efficient energy consumption. Furthermore, under those conditions, liquors showed high contents of phenols (80.28 mg GAE/g of RW) and flavonoids (44.51 RE/g) with significant antioxidant activities (112.07 and 102.30 mg TE/g, measured by ABTS and FRAP tests, respectively). Additionally, the solubilized hemicelluloses were structurally characterized by HPAEC-PAD, MALDI-TOF-MS, FTIR and TGA/DSC, and HPLC-ESI-MS analysis allowed the tentative identification of 17 phytochemicals.Ministerio de Economía y Competitividad | Ref. PID2019-110031RB-I00Xunta de Galicia | Ref. ED431C 2017/62-GRCMinisterio de Ciencia e Innovación | Ref. FPU21/02446Ministerio de Ciencia e Innovación | Ref. PRE 2020 093359Ministerio de Ciencia e Innovación | Ref. RYC2018-026177-IXunta de Galicia | Ref. ED481B-2022-02
Isolation and characterization of cellulose nanofibers from argentine tacuara cane (Guadua angustifolia kunth)
New trends in the area of material improvement are the use of natural nano-charges from renewable biomass, improving the value and sustainability of our country’s natural products. Bamboo is widely used in many countries of the world, although in Argentina, despite being commercialized and exported for the manufacture of wood floors, it goes unnoticed despite having native species. Therefore, researchers identified the native and exotic species present in our country and are working on novel uses. In this context, it is proposed the Argentine Tacuara Cane (Guadua Angustifolia Kunth), endemic plant as a new source of nanocellulosic materials, where stem fibers have been isolated using a green method achieving with yield of 45.9% of cellulose. The cellulose nanofibrils (CNF) were obtained using a green homogenization method. The CNF exhibited web-like long fibrous structure with the diameter of 10-20 nm. The crystallinity was 65.5%, as for the onset temperature of thermal decomposition was 212°C. The nanocellulose isolated from the Tacuara Cane seed fibers has a high potential to be used as a new source of cellulose-based nanofiller for the reinforcement of bionanocomposite films.Fil: Rodriguez Ramirez, Carlos Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Rol, Fleur. Université Grenoble Alpes; FranciaFil: Bras, Julien. Université Grenoble Alpes; FranciaFil: Dufresne, Alain. Université Grenoble Alpes; FranciaFil: Garcia, Nancy Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: D'accorso, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; Argentina. Universidad de Buenos Aires; Argentin
Synergetic effect of hydrothermal and deep eutectic solvents (DES) pretreatments on Robinia wood fractionation for the manufacture of bioethanol and cellulose nanocrystals
This study dealt with the use of environmentally friendly processes based on microwave-assisted autohydrolysis (MAA) and deep eutectic solvents (DES) for the selective fractionation of Robinia pseudoacacia wood (RW) within a biorefinery approach. MAA enabled the recovery of 76% of hemicelluloses in the form of oligomers. Afterwards, different conditions were assessed for the optimal delignification of RW with the DES choline chloride combined with lactic acid reaching delignification ratios up to 86%. Two different methods were accomplished to valorize the cellulosic-rich solid fraction after delignification: (i) bioethanol via enzymatic-fermentative pathway (attaining 53.3 g ethanol/L, about 83% of ethanol yield), and (ii) cellulose nanocrystals (length of 27–550 nm, width of 2–12 nm). Hence, this study presents a novel multiproduct biorefinery to selectively separate the main components of RW and valorize its cellulosic fraction using eco-friendly proceduresUniversidade de Vigo/CISUGMinisterio de Economía| Ref. PID2019-110031RB-I00Xunta de Galicia | Ref. ED431C 2017/62-GRCMinisterio de Ciencia, Innovación y Universidades | Ref. FPU21/02446Ministerio de Ciencia, Innovación y Universidades | Ref. PRE2020-093359Ministerio de Ciencia, Innovación y Universidades | Ref. RYC2018-026177-IXunta de Galicia | Ref. ED481B-2022-02
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