DCAAA. Artículos de Investigación
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- PublicaciónAcceso abiertoNanosensors in clinical development of CAR-T cell immunotherapy(2022-06-15)Immunotherapy using CAR-T cells is a new technological paradigm for cancer treatment. To avoid severe side effects and tumor escape variants observed for conventional CAR-T cells approach, adaptor CAR technologies are under development, where intermediate target modules redirect immune cells against cancer. In this work, silicon nanowire field-effect transistors are used to develop target modules for an optimized CAR-T cell operation. Focusing on a library of seven variants of E5B9 peptide that is used as CAR targeting epitope, we performed multiplexed binding tests using nanosensor chips. These peptides had been immobilized onto the sensor to compare the transistor signals upon titration with anti-La 5B9 antibodies. The correlation of binding affinities and sensor sensitivities enabled a selection of candidates for the interaction between CAR and target modules. An extremely low detection limit was observed for the sensor, down to femtomolar concentration, outperforming the current assay of the same purpose. Finally, the CAR T-cells redirection capability of selected peptides in target modules was proven successful in an in-vitro cytotoxicity assay. Our results open the perspective for the nanosensors to go beyond the early diagnostics in clinical cancer research towards developing and monitoring immunotherapeutic treatment, where the quantitative analysis with the standard techniques is limited.
- PublicaciónAcceso abiertoIdentificación de Bacterias Diazotróficas Rizosféricas y Endófitas Asociadas a Lycopersicon Esculentum Mill en el Norte de Santander, Colombia(2020-10-01)Las bacterias diazotróficas pueden estimular el crecimiento del cultivo del tomate (Lycopersicon esculentum Mill.) mediante la síntesis de hormonas, fijación de N y producción de siderófo-ros, u otros procesos. Las bacterias diazotróficas predominantes en los agroecosistemas pueden ser biofertilizantes potenciales. El objetivo del estudio fue cuantificar y caracterizar la población de bacterias diazotróficas rizosféricas en muestras de suelo rizosféri-co (SR) y bacterias diazotróficas endófitas en muestras de raíces (R) y material foliar (MF), mediante pruebas fenotípicas y mole-culares. El estudio fue exploratorio y con un muestreo aleatorio, con 18 muestras SR, raíces (R) y MF de cultivos de tomate en seis fincas. Las diferencias en el número más probable (NMP) de bacterias diazotróficas no fueron significativas entre los sitios de las muestras de MF y R. La media de NFb mostró diferencias altamente significativas en Azotobacter sp. y Azospirillum sp. entre las muestras de SR, R y MF, con un NMP mayor y menor en SR y MF. Esto se relaciona con la caracterización fenotípica y bio-química de SR donde se identificaron 14 aislados como Azoto-bacter sp. y siete como Azospirillum sp. Los géneros Burkholderia y Gluconacetobacter no mostraron diferencias significativas en el número de aislados entre muestras de SR y R, pero sí respecto a MF, con la población celular menor. Las diferencias entre las fincas no fueron significativas en las variables del suelo relacio-nadas con la disimilitud de NMP. La caracterización molecular permitió identificar A. chroococcum, A. nigricans, A.vinelandii, A. brasilense, B. glumae y G. azotocaptans/G. johannae en muestras de SR; B. glumae, G. azotocaptans/G. johannae en muestras de R y G. azotocaptans/G. johannae en muestras de MF.
- PublicaciónAcceso abiertoBiological activity of sacha inchi (Plukenetia volubilis linneo) and potential uses in human health. A review(Food Technology and Biotechnology, 2021-07-13)Sacha inchi (Plukenetia volubilis Linneo) is an ancestral plant originating in the Amazon jungle that has been adopted as a food source due to its high nutritional value, which has gradually been recognized to have potential benefits for human health. Diverse prospective studies have evaluated the effect of consuming components from the plant, derivatives from its seeds, leaves and shell on preventing the risk of cardiovascular disease, chronic inflammatory disease, dermatitis and controlling tumor proliferation, especially given its recognized high content of essential fatty acids, phenolic compounds and vitamin E, showing antioxidant, hypolipidemic, immunomodulation and emollient activity, as well as the capacity to remove heavy metals from aqueous solutions. This review offers a complete description of the existing information on the use and biological activity of P. volubilis L., based on its essential lipid components and evidenced on its use in the field of human health, in prevention, therapeutic and nutritional contexts, along with industrial uses, making it a promising bioresource.
- PublicaciónAcceso abiertoImmunological Memory to Zika Virus in a University Community in Colombia, South America(2020-05-29)Zika virus appeared in South America in 2015, generating alarm worldwide as it causes microcephaly and autoimmunity. This study aims to determine the serological footprint of the incoming epidemic in a student community and to characterize the memory functional cell response during post convalescence. In a cross-sectional study, Zika-specific IgG using LIA immunoassay was found in 328 university students (CI=95%), while in the second phase, the functional cellular memory response for IFN-γ and IL-2 was quantified using post-stimulus ELISpot with inactivated virus, starting with individuals seropositive for Zika and control individuals (seropositive only for Dengue and seronegative for Zika-Dengue). Depending on the antigen used, memory humoral response (IgG) against Zika Virus was observed in >60% of the population; seropositivity for NS1 was 21.1% higher than E antigen with high intensity. The analysis of cell functionality in 22 individuals seropositive for Zika virus revealed either IFN-γ+ or IL-2+ cells in 86.3% of cases (Th1 profile), presenting multifunctionality in 50% (11 individuals), 64% of which presented> 6 SFC/104 PBMCs (>600 SFC/106 PBMC), reflecting memory circulating cells. A good agreement (Kappa= 0.754) was observed between the coexistence of both cellular and humoral responses but not in their intensity.
- PublicaciónAcceso abiertoAlteraciones tiroideas en diabetes mellitus tipo 2 - Thyroid alterations in type 2 diabetes mellitus(Revista Latinoamericana de Hipersensible, 2019-10-01)Diabetes mellitus is one of the world’s leading non-communicable diseases. It leads to alterations in glucose metabolism due to the low availability of insulin or resistance to its action. Recent studies indicate that there is a relationship between diabetes mellitus and thyroid dysfunction, mediated by disturbances in the hypothalamus - pituitary - thyroid axis, and reduced deiodinase activity, synergism of mitogenic routes, increased inflammatory status, oxi-dative stress and insulin resistance. The most frequent alteration is subclinical hypothyroidism and it occurs more frequently in women, so it is suggested to periodically perform the thyroid profile to these patients. It is necessary that in clinical practice these implications are taken into account in order to provide timely treatment, improve complications such as cardiovascular disease and reduce morbidity and mortality rates.