The development of rHDL-radionuclide theragnostic systems requires evaluation of the absorbed doses that would be produced in healthy tissues and organs at risk. Technetium-99m is the most widely ...used radionuclide for diagnostic imaging, therefore, the design of theragnostic reconstituted high density-lipoprotein (rHDL) nanosystems labeled with Technetium-99m offers multiple possibilities. Objective: To determine the biokinetics, radiopharmacokinetics and estimate the absorbed doses induced in healthy organs by Technetium-99m transported in the core and on the surface of rHDL. Methods: Biokinetic and radiopharmacokinetic models of rHDL/99mTcTc-HYNIC-DA (Technetium-99m in the core) and 99mTcTc-HYNIC-rHDL (Technetium-99m on the surface) were calculated from their ex vivo biodistribution in healthy mice. Absorbed doses were estimated by the MIRD formalism using OLINDA/EXM and LMFIT softwares. Results: rHDL/99mTcTc-HYNIC-DA and 99mTcTc-HYNIC-rHDL show instantaneous absorption in kidney, lung, heart and pancreas, with slower absorption in spleen. rHDL/99mTcTc-HYNIC-DA is absorbed more slowly in the intestine, while 99mTcTc-HYNIC-rHDL is absorbed more slowly in the liver. The main target organ for rHDL/99mTcTc-HYNIC-DA, which is hydrophobic in nature, is the liver, whereas the kidney is for the more hydrophilic 99mTcTc-HYNIC-rHDL. Assuming that 925 MBq (25 mCi) of Technetium-99m, carried in the core or on the surface of rHDL, are administered, the maximum tolerated doses for the organs of greatest accumulation are not exceeded. Conclusion: Theragnostic systems based on 99mTc-labeled rHDL are safe from the dosimetric point of view. The dose estimates obtained can be used to adjust the 99mTc-activity to be administered in future clinical trials.
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Gray cast iron (GCI) is a common material in the automotive industry due to its mechanical characteristics, which change primarily for materials employed for the foundry and cooling rate of material. ...According to the workpiece, the material of the cutting tool and cutting parameters are analyzed to improve the machining and to increment the lifetime of the tools. In this research, the foundry and machining process of an automotive component using ceramic and coated carbide tools were the study case, and the effect that they have on the age strengthening of GCI on the tool wear of the cutting tools was studied. Both inserts have the capability to machine the material with a rough surface between 1.5 to 2.0 μm. The wear mechanism of inserts and the microstructure of GCI were characterized with microscopy techniques, atomic force microscope (AFM), and energy dispersive X-ray spectroscopy (EDS). The microstructure of the workpiece shows a casting with flake graphite morphology that is linked with the induction of microcracks in the material. The experimental analysis shows that the GCI with 12 days of aging has an increased tensile strength. This improves the tool life of ceramic and coated carbide tools. There is a 50% reduction in flank wear with inserts that are machined with the GCI within five days of aging, compared with the material within twelve days. The rake face and flank wear show that abrasive and adhesive wear are the main mechanisms of ceramic inserts due to the high cutting speed. Meanwhile, adhesive and oxidative wear in the flank were the predominant type of wear for coated carbide tools.
There are several unmet needs in modern immunology. Among them, vaccines against parasitic diseases and chronic infections lead.
, the causative agent of Chagas disease, is an excellent example of a ...silent parasitic invasion that affects millions of people worldwide due to its progression into the symptomatic chronic phase of infection. In search for novel vaccine candidates, we have previously introduced Traspain, an engineered trivalent immunogen that was designed to address some of the known mechanisms of
immune evasion. Here, we analyzed its performance in different DNA prime/protein boost protocols and characterized the systemic immune response associated with diverse levels of protection. Formulations that include a STING agonist, like c-di-AMP in the boost doses, were able to prime a Th1/Th17 immune response. Moreover, comparison between them showed that vaccines that were able to prime polyfunctional cell-mediated immunity at the CD4 and CD8 compartment enhanced protection levels in the murine model. These findings contribute to a better knowledge of the desired vaccine-elicited immunity against
and promote the definition of a vaccine correlate of protection against the infection.
The COVID-19 pandemic had a great impact on the mental health of the university population, so managing alternatives to adapt is essential. Objective. The purpose of the study was to analyze the ...moderating effect of physical activity (PA) on the anxiety levels generated by the experiences during the COVID-19 pandemic in university students. Method. A cross-sectional, correlational-explanatory study was carried out in university students (n = 922; 36.66% men and 63.34% women; 19.97 ± 2.92 years). An ad hoc questionnaire was applied to measure fear to COVID-19, as well as the CUXOS-D for anxiety levels and the IPAQ-s to assess PA. Descriptive, inferential and moderation analyzes were performed, in addition to the exploratory and confirmatory factorial for the CUXOS-D. Results. The influence of fear to COVID-19 on cognitive anxiety levels is observed, which is moderated by high PA levels (F 3,918 = 21.58; p <.001). Likewise, it is observed that women perceive greater anxiety and perform less PA than men. The factor analysis of the CUXOS-D was satisfactory. Conclusion. Physical activity can have positive effects that moderate the impact generated by COVID-19 over anxiety in the university community.
La pandemia por COVID-19 tuvo gran impacto sobre la salud mental de la población universitaria, por lo que gestionar alternativas para adaptarse resulta fundamental. Objetivo. El propósito del estudio fue analizar el efecto moderador de la actividad física (AF) sobre los niveles de ansiedad generados por las vivencias durante la pandemia por COVID-19 en estudiantes universitarios. Método. Se realizó un estudio transversal, correlacional-explicativo en estudiantes universitarios (n = 922; 36.66% hombres y 63.34% mujeres; 19.97 ±2.92 años). Se aplicó un cuestionario ad hoc para medir el miedo al COVID-19, así como el CUXOS-D para los niveles de ansiedad y el IPAQ-s para evaluar la AF. Se realizaron análisis descriptivos, inferenciales y de moderación, además del factorial exploratorio y confirmatorio para el CUXOS-D. Resultados. Se observa la influencia del miedo al COVID-19 sobre los niveles de ansiedad cognitiva, la cual es moderada por los niveles de AF alta (F 3,918 = 21.58; p < .001). Asimismo, se observa que las mujeres perciben mayor ansiedad y realizan menor AF que los hombres. El análisis factorial del CUXOS-D fue satisfactorio. Conclusión. La AF puede tener efectos positivos que moderen el impacto generado por el COVID-19 sobre la ansiedad en la comunidad universitaria.
Transporte electrónico a través de moléculas orgánicas Morales Valenzuela, Luis Germán; Iglesias Vázquez, Priscilla Elizabeth; Villarreal Sánchez, Ruben Cesar
Revista de ciencias tecnológicas,
05/2019, Letnik:
2, Številka:
2
Journal Article
Recenzirano
Odprti dostop
El uso de moléculas como componentes electrónicos ha marcado una tendencia de miniaturización en dispositivos conocida como electrónica molecular. En este trabajo se realizan cálculos teóricos del ...coeficiente de transmisión cuántico y la corriente eléctrica a través de una molécula de benceno conectada a terminales eléctricas. El coeficiente de transmisión es obtenido mediante el cálculo recursivo de la función de Green del sistema. Se modela también la influencia de un electrodo móvil puntual (small movable gate SMG) sobre la transmisión. Los resultados muestran que el coeficiente de transmisión oscila como función de la energía incidente de los electrones, y la corriente eléctrica muestra que la molécula de benceno tiene un carácter semiconductor. Las oscilaciones en la transmisión pueden ser manipuladas por la posición de las terminales en la molécula y por la influencia del SMG en una región cercana a un átomo en particular.
Se ha comprobado que los temas de actualidad y los puntos claves para el desarrollo de la neumología y cirugía torácica son comunes independientemente de la comunidad autónoma valorada, aunque con ...realidades bien distintas a la hora de afrontarlos. Esto hace que este tipo de foros, además de enriquecedores al poner de manifiesto las diferencias territoriales existentes, sean necesarios para diseñar estrategias de futuro comunes que puedan ser lideradas desde SEPAR a nivel nacional.
Current issues and key points in the development of pulmonology and thoracic surgery are the same among the different autonomous communities of Spain, although each community takes a very different approach in addressing these issues. As a result, forums that shed light on territorial differences are not only informative, but are also essential for designing common SEPAR-led strategies for the future at a countrywide level.
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