Hydrogen sulfide pathway and skeletal muscle: an introductory review.

The presence of the H2 S pathway in skeletal muscle (SKM) has recently been established. SKM expresses the three constitutive H2 S-generating enzymes in animals and humans, and it actively produces H2 S. The main, recognized molecular targets of H2 S, that is, potassium channels and PDEs, have been evaluated in SKM physiology in order to hypothesize a role for H2 S signalling. SKM dysfunctions, including muscular dystrophy and malignant hyperthermia, have also been evaluated as conditions in which the H2 S and transsulfuration pathways have been suggested to be involved. The intrinsic complexity of the molecular mechanisms involved in excitation-contraction (E-C) coupling together with the scarcity of preclinical models of SKM-related disorders have hampered any advances in the knowledge of SKM function. Here, we have addressed the role of the H2 S pathway in E-C coupling and the relative importance of cystathionine β-synthase, cistathionine γ-lyase and 3-mercaptopyruvate sulfurtransferase in SKM diseases

Spread of a SARS-CoV-2 variant through Europe in the summer of 2020.

Following its emergence in late 2019, the spread of SARS-CoV-21,2 has been tracked by phylogenetic analysis of viral genome sequences in unprecedented detail3–5. Although the virus spread globally in early 2020 before borders closed, intercontinental travel has since been greatly reduced. However, travel within Europe resumed in the summer of 2020. Here we report on a SARS-CoV-2 variant, 20E (EU1), that was identified in Spain in early summer 2020 and subsequently spread across Europe. We find no evidence that this variant has increased transmissibility, but instead demonstrate how rising incidence in Spain, resumption of travel, and lack of effective screening and containment may explain the variant’s success. Despite travel restrictions, we estimate that 20E (EU1) was introduced hundreds of times to European countries by summertime travellers, which is likely to have undermined local efforts to minimize infection with SARS-CoV-2. Our results illustrate how a variant can rapidly become dominant even in the absence of a substantial transmission advantage in favourable epidemiological settings. Genomic surveillance is critical for understanding how travel can affect transmission of SARS-CoV-2, and thus for informing future containment strategies as travel resumes. © 2021, The Author(s), under exclusive licence to Springer Nature Limited

"SIMULEX". Simulador en excel para cinética química homogénea

El presente artículo muestra el diseño de un simulador ideado en una hoja de cálculo Excel, el c ual posee un conjunto de archivos en los cuales se trat an diversos temas comprendidos en el área de la Cinéti ca Química. Algunos de los temas tratados en este simulador, son: Cinética Enzimática, Secuencia y Equilibrio de Reacciones Químicas, Análisis Cinétic o de uno y dos Sistemas de Reacciones, entre otros. A sí mismo, mediante el uso de estos simuladores se pretende idear procesos o sistemas de reacción, así como para optimizar procesos ya existentes, en lo q ue interviene algún tipo de reacción química. O bien, se podría emplear como una herramienta didáctica para el estudiante que trate con temas de Cinética Química para un mejor entendimiento de la misma, además de que éste simulador facilita la resolución de ecuaci ones diferenciales complejas que representan el avance d e una reacción química, reduciendo su tiempo de resolución y otorgando resultados confiables y sobr e todo de una manera rápida

Detección de contaminantes orgánicos sobre superficies pasivas por espectroscopia raman estimulada

Entre las docenas de compuestos orgánicos aromáticos que conforman una parte de la contaminación en el ambiente de una ciudad, el naftaleno es un compuesto orgánico semi-volátil (COS) presente en una buena concentración. El naftaleno o también llamado naftalina es un sólido blanco que se evapora fácilmente y se produce naturalmente cuando se queman combustibles, también cuando se quema tabaco o madera se produce naftalina. La exposición a grandes cantidades puede dañar o destruir una porción de los glóbulos rojos. Esto puede hacer que el número de glóbulos rojos disminuya hasta que su cuerpo remplace las células destruidas. Esta condición se llama anemia hemolítica. Se han descrito numeroso casos de anemia hemolítica en niños, incluso en recién nacidos, ya que la naftalina puede pasar de la sangre de una mujer embarazada a la sangre del feto. En este trabajo, se ha seleccionado el naftaleno como molécula modelo porque da un espectro Raman con picos bien definidos en un rango entre 500 y 3000 cm-1. La espectroscopia Raman de superficie promovida (SERS) se usó para la detección de unos cuantos micro-gramos de naftaleno adsorbido sobre papel filtro modificado. La modificación consistió en aplicar un recubrimiento de nano-partículas de Ago sobre el papel usando dos métodos en los cuales se realiza una reacción química de reducción de un compuesto de plata. Al aplicar ésta técnica espectroscópica usando solo papel filtro se determina una cantidad mínima detectable por Raman convencional. Este valor cmd encontrado para el naftaleno, se toma como referencia para probar bajo la misma metodología, papel filtro con recubrimiento de nano-partículas de Ago. Bajo la técnica SERS la señal de los picos detectados fue mucho mayor, posibilitando la cuantificación de este contaminante atmosférico en cantidades menores al cmd encontrad

Caracterización de la super-acidez del carbón sulfatado por espectroscopia

A new acid catalyst based in a carbonaceous solid was functionalized using sulfuric acid as source of –SO.H species. This carbon-based material prepared by the pyrolysis of waste tire rubber was used either as catalyst or as catalytic support. The pyrolysis process was performed with a flow of N. at relatively high temperature to obtain a mesoporous material and after, achieve an effective sulfonation. The sulfonation of char obtained from tire rubber was through direct immersion into concentrated H.SO. under reflux. Chars, original and sulfated, were characterized by several analytic techniques including an elemental analysis. Mainly by Raman and X-ray Photon-electronic spectroscopies. Resultant signals are suggestive of protonic superacidity on sulfonated char, this property being related to the structure of surface sulfonic species.En este trabajo se caracteriza un nuevo material basado en un sólido carbonoso que fue funcionalizado como catalizador super-ácido al usar ácido sulfúrico como fuente de iones sulfonilo –SO.H. Este material carbonoso que se preparó por el proceso de pirólisis aplicado a hule de llanta, puede ser usado como catalizador directamente o bien, como soporte catalítico. El proceso de pirólisis fue realizado con flujo de N. a temperaturas relativamente altas y así obtener un material mesoporoso en base al carbono y que fue sulfonado de forma efectiva. El método de sulfonación del carbón obtenido de hule de llanta fue mediante inmersión en ácido sulfúrico concentrado y a reflujo. Dos muestras de carbón, el original y el sulfonado, fueron caracterizados por medio de diferentes técnicas analíticas, principalmente por las espectroscopías Raman y Fotón-electrónica de rayos-X. Las diversas señales resultantes de estos análisis sugieren super-acidez protónica del carbón sulfonado, siendo tal propiedad relacionada a la estructura de grupos o iones relativos al ácido sulfónico en la superficie del material

Self-cleaning test of doped TiO2-coated glass plates under solar exposure

Photocatalytic films of TiO2 doped with metal oxides, ZnFe 2O4, ZnO, and CuO, were formed on glass plates by the ultraspinning method from Ti(IV) isopropoxide-based sol-gels. To test the self-cleaning properties of TiO2 films on glass, a layer of crystalline fluoranthene, a polycyclic aromatic compound, was placed over the glass by spraying and then exposing it to solar irradiation. The covering of fluoranthene on the 1 wt % metal oxide-doped anatase films was degraded nearly to 100% at 20 h of exposure time. Thus, the coated-glass transparency was recovered totally between 35 and 52 h of exposure time for the doped anatase film, which did not occur with anatase on glass, even after more than 85 h of solar irradiation. For some samples, a correlation was found between the weight losses of the solid compound and the intensity of the Raman vibration at 671 cm-1 during photocatalytic degradation. After 20 h of solar exposure, while the presence of fluoranthene was not detected by Raman spectroscopy, some glass plates presented ultrathin zones of degradation products. Regarding fluoranthene photodegradation and weight loss in the results when the different metal-oxide dopants were compared, a sequential efficiency was observed: ZnFe2O4 > CuO > ZnO. © 2009 American Chemical Society

Study of temperature effect in ?-carotene of carrot by Raman spectroscopy

A micro-Raman system is used to study the ?-carotene of dry and fresh carrot samples in environments with variations of the temperature between 16�C and 120�C. It is shown that the Raman peaks intensities of the dry sample diminish considerably, due to the strong degradation of the ?-carotene with the increment of the temperature. Also, for the fresh sample in deionized water, the Raman peaks intensities of the ?-carotene, starting from 40 to 50�C, diminish, due to its degradation and diffusion on the surface of the sample and in the water. The same tendency is observed for the ?-carotene of the carrot juice

Development and validation of a High Performance Liquid Chromatography-Diode Array Detection method for the determination of aging markers in tequila

The use of Raman spectroscopy to analyze blood biochemistry and hence distinguish between normal and abnormal blood was investigated. Blood samples were obtained from 6 patients who were clinically diagnosed with leukemia and 6 healthy volunteers. The imprint was put under the microscope and several points were chosen for Raman measurement. All the spectra were collected by a confocal Raman micro-spectroscopy (Renishaw) with a NIR 830 nm laser. It is shown that the serum samples from patients with leukemia and from the control group can be discriminated when the multivariate statistical methods of principal component analysis (PCA) and linear discriminated analysis (LDA) are applied to their Raman spectra. The ratios of some band intensities were analyzed and some band ratios were significant and corresponded to proteins, phospholipids, and polysaccharides. The preliminary results suggest that Raman Spectroscopy could be a new technique to study the degree of damage to the bone marrow using just blood samples instead of biopsies, treatment very painful for patients. " 2009 American Institute of Physics.",,,,,,"10.1063/1.3175637",,,"http://hdl.handle.net/20.500.12104/40568","http://www.scopus.com/inward/record.url?eid=2-s2.0-70450200613&partnerID=40&md5=0132a360741d85c8c71d34ceeadf241e",,,,,,,,"AIP Conference Proceedings",,"9