Biosíntesis, caracterización y evaluación de la respuesta antiproliferativa de nanopartículas de plata, obtenidas a base de extractos de annona muricata, sobre líneas celulares de cáncer de mama.

ABSTRACT Currently treatments for breast cancer are expensive and not very accessible, due to this, it requires the development of new routes of administration, treatments and novel materials, such as the one proposed. Carrying out the biosynthesis of silver nanoparticles (AgNPs) using extracts of a plant well known for its anticancer activity known as "Soursop" (Annona muricata); where the main active compounds of A. muricata (in leaves, stems and husk) are acetogenins and polyphenols, among others, which means that they can be used as reducing agents; It should be noted that anticancer activity is directly attributed to acetogenins. The biosynthesized AgNPs with leaf extract (AgNPs-EH) and with shell extract (AgNPs-EC) of A. muricata; were characterized by means of the UV-Vis technique, to observe the optical properties of the AgNPs, comparing the reaction times against the growth of the optical response known as Surface Plasmonic Resonance (RPS), as well as Transmission Electron Microscopy (TEM), to recognize the morphology and the average sizes of nanoparticle, with the help of the Scanning Electron Microscopy (SEM), a chemical mapping was achieved, to observe the distribution of the AgNPs in the medium, as well as with the help of the EDS technique (Energy-dispersive X-ray spectroscopy) the elemental chemical composition of the AgNPs was identified. In addition, by means of FT-IR it was possible to identify the vibrational mode of the functional groups present in the extracts. Achieving elucidate the cell viability of AgNPs in cell lines such as MCF-7, MDA-MB-468 and macrophage

Efficient Removal of Heavy Metals from Aqueous Solutions Using a Bionanocomposite of Eggshell/Ag-Fe

Abstract: Eggshell and an easily synthesized bionanocomposite of eggshell with Ag-Fe nanoparticles demonstrated to be efficient adsorbent materials for the removal of lead, arsenic, and mercury from water. The natural material and the bionanocomposite were characterized by TEM and XRD. Ag-Fe nanoparticles vary from 1 to 100 nm in size. Equilibrium times of the adsorption systems were achieved between 4 and 8 h. The experimental adsorption data fitted the pseudo-second and Elovich models; therefore, the adsorption of heavy metals ions took place mainly by a chemical process. The adsorption capacity of eggshell in mg/g was 7.01 for As5+, 3.90 for Pb2+, and 1.51 for Hg2+, while the nanocomposite adsorption capacity was 17.7 for As5+, 27.8 for Pb2+ and 15.88 for Hg2+

EGF-Coupled Gold Nanoparticles Increase the Expression of CNPase and the Myelin-Associated Proteins MAG, MOG, and MBP in the Septal Nucleus Demyelinated by Cuprizone

ARTICULO DE ACCESO ABIERTOCurrent pharmacological therapies against demyelinating diseases are not quite satisfactory to promote remyelination. Epidermal growth factor (EGF) can expand the population of oligodendrocyte precursor cells (OPCs) that may help with the remyelination process, but its delivery into the injured tissue is still a biomedical challenge. Gold nanoparticles (GNPs) may be a useful tool for drug delivery into the brain. To evaluate remyelination in the septal nucleus, we administered intracerebral GNPs coupled with EGF (EGF–GNPs). C57BL6/J mice were demyelinated with 0.4% cuprizone (CPZ) and divided into several groups: Sham, Ctrl, GNPs, EGF, and EGF–GNPs. We evaluated the remyelination process at two time-points: 2 weeks and 3 weeks post-injection (WPI) of each treatment. We used the rotarod for evaluating motor coordination. Then, we did a Western blot analysis myelin-associated proteins: CNPase, MAG, MOG, and MBP. EGF–GNPs increase the expression of CNPase, MAG, and MOG at 2 WPI. At 3 WPI, we found that the EGF–GNPs treatment improves motor coordination and increases MAG, MOG, and MBP. EGF–GNPs enhance the expression of myelin-associated proteins and improve the motor coordination in mice. Thus, EGF-associated GNPs may be a promising pharmacological vehicle for delivering long-lasting drugs into the brain.S/

Study X-ray photoelectron spectroscopy determination of interactions between gold nanoparticles and epidermal growth factor for potential use in biomedicine

Nowadays, biomedical applications of gold nanoparticles coupled with Epidermal Growth Factor have attracted huge attention because of its theranostic activity, which could be useful for diagnosis and treatment of neurodegenerative diseases. Therefore, there is a great interest to know the nature of the intermolecular interactions between the gold nanoparticles and epidermal growth factor (EGF). A two-step synthesis was performed. In the first step, gold nanoparticles were synthesized by chemical reduction of tetrachloroauric acid using sodium citrate as reducing and capping agent. Secondly, gold nanoparticles were coupled with EGF. The obtained nanoparticles were characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and zeta-potential before and after being coupled with the EGF. Gold nanoparticles with an average diameter of 8.09 nm were obtained. After coupled with EGF, the particle average diameter increased to 9.14 nm. X-ray photoelectron spectroscopy showed an electrostatic interaction between gold nanoparticles and EGF. Zeta potential corroborated these results. Thus, it was possible for the first time to identify the interactions between these two chemical species. Since gold nanoparticles may act as carriers of EGF, these results illustrate the great potential for the use of this bionanocomposite in neurodegenerative disease treatment.UAEME

Ultra‐Small Platinum Nanoparticles with High Catalytic Selectivity Synthesized by an Eco‐friendly Method Supported on Natural Hydroxyapatite

The biosynthesis of Pt-nanoparticles (Pt NPs) supported on bovine bone powder was conducted by an environmentally friendly method that consists on immersing bovine bone powder into a Pt4+ metal ion solution at room temperature, atmospheric pressure and subsequent reduction by Heterotheca inuloides. It is worth pointing out that a calcination process is not required for the synthesis of this catalyst by the method reported herein. The nanocomposite was characterized by transmission electron microscopy (TEM), which revealed uniformly dispersed platinum nanoparticles with quasi-spherical form and average particle size of 7.1 nm. The XPS studies exhibited the presence of 47.62% Pt° and 51.84% PtO. The catalyst activity was tested in the selective hydrogenation of 2-butyne-1,4-diol towards 2-butene-1,4-diol. The nanocomposite exhibits a reasonable catalytic performance with nearly 100% conversion of the alkyne and 96% selectivity towards 2-butene-1,4-diol.CONACY

Antimicrobial Activity of Biogenic Silver Nanoparticles from Syzygium aromaticum against the Five Most Common Microorganisms in the Oral Cavity

ARTICULO DE ACCESO LIBREAbstract: Syzygium aromaticum (clove) has been used as a dental analgesic, an anesthetic, and a bioreducing and capping agent in the formation of metallic nanoparticles. The main objective of this study was to evaluate the antimicrobial effect in oral microorganisms of biogenic silver nanoparticles (AgNPs) formed with aqueous extract of clove through an ecofriendly method “green synthesis”. The obtained AgNPs were characterized by UV-Vis (ultraviolet-visible spectroscopy), SEM-EDS (scanning electron microscopy–energy dispersive X-ray spectroscopy), TEM (transmission electron microscopy), and ζ potential, while its antimicrobial effect was corroborated against oral Grampositive and Gram-negative microorganisms, as well as yeast that is commonly present in the oral cavity. The AgNPs showed absorption at 400–500 nm in the UV-Vis spectrum, had an average size of 4–16 nm as observed by the high-resolution transmission electron microscopy (HR-TEM), and were of a crystalline nature and quasi-spherical form. The antimicrobial susceptibility test showed inhibition zones of 2–4 mm in diameter. Our results suggest that AgNPs synthesized with clove can be used as effective growth inhibitors in several oral microorganisms.S/

Green Synthesis of Silver Nanoparticles Using Heterotheca inuloides and Its Antimicrobial Activity in Catgut Suture Threads

Abstract Silver nanoparticles were synthesized through a green method, using Heterotheca inuloides as a bioreducing agent. Moreover, catgut suture threads were decorated with those biogenic silver nanoparticles, and their antibacterial activity versus highly resistant pathogenic microorganisms was evaluated. The principles of green chemistry and nanotechnology allow us to obtain advanced materials, such as suture threads, which can reduce or avoid the prevalence of infectious processes in the medical field. Mexican medicinal plants, such as H. inuloides, represent an adequate alternative for biosynthesis; this plant species is known for its medicinal benefits and its antibacterial activity, and for that reason, it is being used in folk medicine

Pedagogía para la práctica educativa del siglo XXI

La obra es coordinada por el doctor René Pedroza Flores, investigador del Instituto de Estudios Sobre la Universidad (iesu), de la uaem; miembro del Sistema Nacional de Investigadores (sni), nivel 2, e integrante regular en la Academia Mexicana de las Ciencias. En este libro participan profesoresinvestigadores miembros expertos en la temática y pertenecientes a nuestra universidad, así como investigadores de importante prestigio internacional en diversas disciplinas. En este sentido, destacan las investigaciones de los españoles Clara Ventura Obrador, Gloria Alguacil Buchna y el colombiano Carlos Alberto Jiménez Vélez; además de la colaboración de la antropóloga francesa Noemí Paymal. Asimismo, son relevantes las contribuciones de los investigadores mexicanos Salvador Soriano y Mónica E. Soriano. Las propuestas incluidas en Pedagogía para la práctica educativa del siglo xxi están encaminadas a conformar mejores sociedades en nuestra era, considerando que la comprensión de estas posturas y su aplicación en diversos contextos específicos representará una posibilidad para edificar sociedades mucho más justas, equitativas y humanas; sobre todo en ámbitos profesionales y universitarios urgentes de subsanar problemáticas en los procesos mundiales educativos de hoy.Pedagogía para la práctica educativa del siglo xxi es una obra que muestra cómo la dinámica de la sociedad actual lleva a concebir la educación de una forma diferente de la visión prevaleciente en la actualidad, la cual reconoce en las competencias y las habilidades el único medio para lograr en los individuos su desarrollo e inserción social. El presente libro otorga al lector un panorama epistemológico, metodológico y teórico del nacimiento de un nuevo paradigma pedagógico, al considerar que una pedagogía humana implica la enseñanza integral y holística posible, mediante el uso de diversos recursos de enseñanza-aprendizaje acordes con la formación de las sociedades de nuestro siglo.UAE

Síntesis verde de nanopartículas metálicas

La nanotecnología permite manipular y dividir la materia a escalas nanométricas, en especial, los metales, cuyas propiedades pueden ser aplicadas en diversas áreas, comola médica. Es necesario conocer los mecanismos utilizados para la síntesis de nanomateriales que utilizamos en nuestras actividades cotidianas. Con el desarrollo de la biotecnología se han desarrollado mecanismos que permiten la obtención de nanopartículas por métodos verdes, los cuales tienen grandes ventajas y se presentan en este artículo

Un pueblo se levanta: causas y significado. Diálogos del Pensamiento 272

Entre Asia y Europa, entre la tradición y la apertura, entre el clima meteorológico más inhóspito y el clima político más caliente, la experiencia revolucionaria de inicios del siglo XX de Rusia, impactó y tuvo repercusiones en todo el mundo que aún hoy tienen presencia. En el centenario de su conmemoración vale la pena recordar su contexto y reflexionar sobre sus implicaciones en América Latina, motivo que reúne en esta primer emisión sobre el tema al Dr. Jaime Tamayo, y las Doctoras Claudia Gamiño, Guadalupe Moreno y Guadalupe López quienes nos hablan sobre las condiciones que llevan al estallamiento de esta Revolución, qué enfrentamientos o conflictos sociales resultan predeterminantes en el camino que toma y su posterior triunfo, cuáles fueron las principales ideas y corrientes filosóficas y políticas que la influenciaron, cuáles fueron las principales repercusiones o impactos que tuvo la Revolución sobre la población y la forma de gobierno Ruso; además de invitarnos al Coloquio: Impactos de la Revolución Rusa en México y América Latina que se organiza en nuestro Centro Universitario y que se llevará a cabo los próximos 8 y 9 de noviembre