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1.
Environ Sci Process Impacts ; 25(4): 704-726, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-36752881

RESUMEN

According to the World Health Organization, both indoor and urban air pollution are responsible for the deaths of around 3.5 million people annually. During the last few decades, the interest in understanding the composition and health consequences of the complex mixture of polluted air has steadily increased. Today, after decades of detailed research, it is well-recognized that polluted air is a complex mixture containing not only gases (CO, NOx, and SO2) and volatile organic compounds but also suspended particles such as particulate matter (PM). PM comprises particles with sizes in the range of 30 to 2.5 µm (PM30, PM10, and PM2.5) and ultrafine particles (UFPs) (less than 0.1 µm, including nanoparticles). All these constituents have different chemical compositions, origins and health consequences. It has been observed that the concentration of PM and UFPs is high in urban areas with moderate traffic and increases in heavy traffic areas. There is evidence that inhaling PM derived from fossil fuel combustion is associated with a wide variety of harmful effects on human health, which are not solely associated with the respiratory system. There is accumulating evidence that the brains of urban inhabitants contain high concentrations of nanoparticles derived from combustion and there is both epidemiological and experimental evidence that this is correlated with the appearance of neurodegenerative human diseases. Neurological disorders, such as Alzheimer's and Parkinson's disease, multiple sclerosis, and cerebrovascular accidents, are among the main debilitating disorders of our time and their epidemiology can be classified as a public health emergency. Therefore, it is crucial to understand the pathophysiology and molecular mechanisms related to PM exposure, specifically to UFPs, present as pollutants in air, as well as their correlation with the development of neurodegenerative diseases. Furthermore, PM can enhance the transmission of airborne diseases and trigger inflammatory and immune responses, increasing the risk of health complications and mortality. Therefore, understanding the different levels of this issue is important to create and promote preventive actions by both the government and civilians to construct a strategic plan to treat and cope with the current and future epidemic of these types of disorders on a global scale.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Ambientales , Humanos , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Sistema Nervioso/química , Tamaño de la Partícula
2.
Molecules ; 26(24)2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34946522

RESUMEN

As surface-enhanced Raman spectroscopy (SERS) continues developing to be a powerful analytical tool for several probes, four important aspects to make it more accessible have to be addressed: low-cost, reproducibility, high sensibility, and recyclability. Titanium dioxide nanotubes (TiO2 NTs) prepared by anodization have attracted interest in this field because they can be used as safe solid supports to deposit metal nanoparticles to build SERS substrate nanoplatforms that meet these four desired aspects. TiO2 NTs can be easily prepared and, by varying different synthesis parameters, their dimensions and specific features of their morphology can be tuned allowing them to support metal nanoparticles of different sizes that can achieve a regular dispersion on their surface promoting high enhancement factors (EF) and reproducibility. Besides, the TiO2 photocatalytic properties enable the substrate's self-cleaning property for recyclability. In this review, we discuss the different methodological strategies that have been tested to achieve a high performance of the SERS substrates based on TiO2 NTs as solid support for the three main noble metal nanoparticles mainly studied for this purpose: Ag, Au, and Pt.

3.
Nanotechnology ; 32(8): 085602, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33166942

RESUMEN

Functionalized carbon nanospheres have been synthesized in situ via a facile chemical vapor deposition strategy, fabricated by the pyrolysis of toluene/ethanol mixtures at different percentages (0, 1, 2, 3, 4, and 5 wt% of ethanol). The as-grown nanospheres have been characterized using transmission electron microscopy, scanning electron microscopy, Raman and Fourier transform infrared spectroscopy, x-ray diffraction, nitrogen adsorption, zeta potential measurements and x-ray photoelectron spectroscopy. Results indicate that the incorporation of ethanol in the precursor solution reflected in the presence of oxygen and hydrogen functional groups, the highest functionalized nanospheres without compromising the morphology of the sample were yielded at 3 wt% concentration. These in situ added functional groups rendered the carbon nanostructures enhancedly dispersible and stable in water, avoiding post-synthesis and harsh chemicals processing; envisaging thus applications of the nanospheres in the biomedical field where hydrophilicity of the nanomaterials is mandatory.

4.
Molecules ; 25(20)2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-33066356

RESUMEN

Transition metal-based compounds have shown promising uses as therapeutic agents. Among their unique characteristics, these compounds are suitable for interaction with specific biological targets, making them important potential drugs to treat various diseases. Copper compounds, of which Casiopeinas® are an excellent example, have shown promising results as alternatives to current cancer therapies, in part because of their intercalative properties with DNA. Vanadium compounds have been extensively studied for their pharmacological properties and application, mostly in diabetes, although recently, there is a growing interest in testing their activity as anti-cancer agents. In the present work, two compounds, [Cu(Metf)(bipy)Cl]Cl·2H2O and [Cu(Impy)(Gly)(H2O)]VO3, were obtained and characterized by visible and FTIR spectroscopies, single-crystal X-ray diffraction, and theoretical methods. The structural and electronic properties of the compounds were calculated through the density functional theory (DFT) using the Austin-Frisch-Petersson functional with dispersion APFD, and the 6-311 + G(2d,p) basis set. Non-covalent interactions were analyzed using Hirshfeld surface analysis (HSA) and atom in molecules analysis (AIM). Additionally, docking analysis to test DNA/RNA interactions with the Casiopeina-like complexes were carried out. The compounds provide metals that can interact with critical biological targets. In addition, they show interesting non-covalent interactions that are responsible for their supramolecular arrangements.


Asunto(s)
Antineoplásicos/química , Cobre/química , Compuestos Organometálicos/química , Compuestos de Vanadio/química , Antineoplásicos/síntesis química , Cristalografía por Rayos X , ADN/química , ADN/metabolismo , Teoría Funcional de la Densidad , Simulación del Acoplamiento Molecular , Compuestos Organometálicos/síntesis química , ARN de Transferencia/química , ARN de Transferencia/metabolismo , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Compuestos de Vanadio/síntesis química
5.
Heliyon ; 5(7): e02139, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31372569

RESUMEN

Carbon black (CB), a material consisting of finely divided particles, can be obtained by the partial combustion of heavy petroleum feedstock. The commercial preparation of CB nanoparticles require sophisticated equipment, chemical pre-treatment, and combination of complex separation and purification techniques. CB nanoparticles can also be recovered from scrubbed rubber, but yields are modest and the process is technically complex. Here, we report the development of a simple and inexpensive method for the preparation of CB nanoparticles from waste tires. Under optimal conditions, the yield of recovered CB nanoparticles (∼22 nm) was of approximately 81%; the nanomaterial presents good thermal stability and conductivity, and forms chain-like agglomerates; chemical composition analysis and solubility tests indicates that it is partly oxidized (C, 84.9%; S, 10.21%; O, 4.9%). The product was fully characterized by FTIR, Raman, TGA, BET, SEM and TEM. This preparation method could become a viable alternative to reduce the large amount of waste tires and decreasing their negative environmental impact, producing good quality CB nanoparticles useful for batteries, sensors, electronic devices, catalysis, pigments, concrete, and plastics, among many other applications.

6.
Rev Med Inst Mex Seguro Soc ; 57(3): 170-180, 2019 05 02.
Artículo en Español | MEDLINE | ID: mdl-31995344

RESUMEN

The respiratory system is commonly known for being responsible for gaseous exchange. However, chronic exposure to air born pollution increases each year the number of asthma, chronic obstructive pulmonary disease (COPD), and lung cancer cases, which compels us to view the lung as a vulnerable organ due to the fact that because of its nature it enters in contact with substances present in the environment. Fortunately, the immune response mechanism acts locally in the lung in order to modulate the inflammatory response and to facilitate the clearance of inhaled pathogens, as well as volatile organic compounds (VOCs), metals, sulphur and nitrogen oxides, ozone and particulate matter (PM). Expanding our understanding of the molecular mechanisms underlying inflammation and pathology induced by airborne contaminant particles in the long term can help to develop strategies to reduce the risks of exposure to some of the most hazardous air pollutants, as well as to reduce the toxicity of nanomaterials and may also help to identify therapeutic targets to be used in the preventive treatment of susceptible groups.


El sistema respiratorio es comúnmente conocido por ocuparse del intercambio gaseoso; sin embargo, la exposición crónica a contaminantes del aire aumenta cada año el número de casos nuevos de asma, enfermedad pulmonar obstructiva crónica (EPOC) y cáncer de pulmón, lo que nos obliga a ver el pulmón como un órgano vulnerable, ya que por su naturaleza entra en contacto con sustancias presentes en el medio ambiente. Afortunadamente, el mecanismo de respuesta inmune actúa localmente en el pulmón para modular respuestas inflamatorias y para facilitar el aclaramiento de patógenos inhalados, así como de compuestos orgánicos volátiles (VOCs, por sus siglas en inglés), metales, óxidos de azufre y nitrógeno, ozono y materia particulada (PM, por sus siglas en inglés). Ampliar nuestra comprensión de los mecanismos moleculares que subyacen a la inflamación y a la patología inducida por partículas contaminantes en las vías respiratorias a largo plazo puede ayudar a desarrollar estrategias para reducir los riesgos de exposición a algunos de los contaminantes atmosféricos más peligrosos, así como a reducir la toxicidad de los nanomateriales y quizás pueda también ayudar a identificar objetivos terapéuticos que se puedan utilizar en el tratamiento preventivo de grupos susceptibles.


Asunto(s)
Contaminantes Atmosféricos/inmunología , Pulmón/inmunología , Material Particulado/inmunología , Contaminantes Atmosféricos/toxicidad , Asma/etiología , Tracto Gastrointestinal/anatomía & histología , Humanos , Sistema Inmunológico , Pulmón/embriología , Neoplasias Pulmonares/etiología , Material Particulado/toxicidad , Enfermedad Pulmonar Obstructiva Crónica/etiología , Sistema Respiratorio/anatomía & histología , Sistema Respiratorio/inmunología
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