The membrane depolarization and increase intracellular calcium level produced by silver nanoclusters are responsible for bacterial death

This work highlights how our silver ultra nanoclusters (ARGIRIUM-SUNc) hand-made synthesized, are very useful as a bactericide and anti-biofilm agent. The Argirium-SUNc effective antibacterial concentrations are very low (< 1 ppm) as compared to the corresponding values reported in the literature. Different bacterial defense mechanisms are observed dependent on ARGIRIUM-SUNc concentrations. Biochemical investigations (volatilome) have been performed to understand the pathways involved in cell death. By using fluorescence techniques and cell viability measurements we show, for the first time, that membrane depolarization and calcium intracellular level are both primary events in bacteria death. The ARGIRIUM-SUNc determined eradication of different biofilm at a concentration as low as 0.6 ppm. This suggests that the effect of the nanoparticles follows a common mechanism in different bacteria. It is highly probable that the chemical constitution of the crosslinks could be a key target in the disrupting mechanism of our nanoparticles. Since the biofilms and their constituents are essential for bacterial survival in contact with humans, the silver nanoparticles represent a logical target for new antibacterial treatments

Wunderlich syndrome (spontaneous renal hematoma) as a cause of acute abdomen: a case report

Spontaneous renal hemorrhage, also known as Wünderlich syndrome, is a rare condition that can be life-threatening and consists of the onset of sudden hemorrhage into the subcapsular and perirenal spaces. It can be lethal as it goes unnoticed and requires aggressive treatment. The entity lies mainly in neoplasms, the malignant ones being the most common. We present the case of a 63-year-old female patient with acute abdomen clinic, a diagnostic laparoscopy was performed and renal hematoma was evidenced as the cause of the symptoms. It was managed conservatively without any complications. We emphasize the importance of keeping in mind Wünderlich syndrome as a differential diagnosis to instigate early treatment for a better outcome.

CONSTRUCCIÓN DE UN MICROSCOPIO PERFILOMETRICO POR INTERFEROMETRÍA DE LUZ BLANCA

En este trabajo se presenta el diseño y construcción de un microscopio perfilométrico por interferometría de luz blanca, que permite el levantamiento topográfico de objetos con resolución nanométrica. Por medio de un escaneo axial del objeto, se adquiere un conjunto de imágenes con franjas interferométricas deformadas las cuales dan información de la rugosidad del objeto. El principio del sistema está basado en la localización del pico de coherencia en cada posición Im(i,j) del conjunto de m imágenes adquiridas, en donde la posición z(m) del pico de coherencia cambia de acuerdo a la topografía del objeto. Se presenta una serie de reconstrucciones tridimensionales de varios objetos a resolución nanométrica, obtenidas de manera automática con la ayuda de una interface gráfica elaborada en Matlab, que permite el control de los dispositivos, procesado digital de las imágenes y el cálculo de la topografía del objeto

INTERFAZ GRAFICA PARA EL ANÁLISIS DE LAS FUERZAS DE CAPTURA EN UNA PINZA ÓPTICA USANDO LAS APROXIMACIONES DE RAYLEIGH Y MIE

En este trabajo se desarrolla una Interfaz Gráfica de Usuario en el software MATLAB,  que facilita el análisis de las fuerzas de la luz responsables de la captura de esferas dieléctricas con una pinza óptica tipo gradiente, y que implementa los “Métodos aproximados”, en particular: el “Método Dipolar de Rayleigh” que usa ecuaciones de la electrodinámica para modelar el comportamiento de las fuerzas de captura y el “Método de Rayos Ópticos” que usa la óptica geométrica, permitiendo por medio de ecuaciones sencillas, obtener una aproximación al comportamiento de las fuerzas de captura..Palabras Clave: Pinza óptica, régimen de Rayleigh, régimen de Mie, fuerza de gradiente, fuerza de Scattering

VIBRACIONES DE MEMBRANAS RECTANGULARES Y CIRCULARES: SOLUCIÓN ANALÍTICA, SIMULACIÓN, Y SOLUCIÓN NUMÉRICA

En este trabajo se presentan soluciones exactas de ecuaciones diferenciales parciales para membranas circulares y rectangulares fijas en los bordes. Se realizan simulaciones en 2 y 3 dimensiones para los modos de vibración de la membrana circular y se solucionan la ecuación de onda de la membrana rectangular numéricamente utilizando el método de elementos finitos. Tanto para las simulaciones de la membrana circular como la solución numérica de la membrana rectangular se utiliza Matlab. Se presentan resultados de la simulación de la membrana circular para los modos normales de vibración (0,1), (0,2), (0,3), (1,1), (1,2), (1,3), (2,1), (2,2) y (2,3) y los resultados de la solución numérica de la membrana rectangular para los modos (1,1), (1,2), (1,3), (2,1), (2,2), (2,3), (3,1), (3,2) y (3,3)

Hydroxylated phosphines as ligands for chalcogenide clusters: Self assembly, transformations and stabilization

© 2017 IUPAC & De Gruyter.This contribution is a documentation of recent advances in the chemistry of chalcogenide polynuclear transition metal complexes coordinated with mono-and di-phosphines functionalized with hydroxo groups. A survey of complexes containing tris(hydroxymethyl)phosphine (THP) is presented. The influence of the alkyl chain in bidentate phosphines, bearing the P-(CH2)x-OH arms, is also analyzed. Finally, isolation and structure elucidation of the complexes with HP(OH)2, P(OH)3, As(OH)3, PhP(OH)2, stabilized by coordination to Ni(0) and Pd(0) centers embedded into chalcogenide clusters, is discussed

Exploring the capability of yeasts isolated from colombian fermented cocoa beans to form and degrade biogenic amines in a lab-scale model system for cocoa fermentation

Yeast starters for cocoa fermentation are usually tested according to their enzymatic activities in terms of mucilage degradation and flavor improvement, disregarding their influence on the production or elimination of toxic compounds as biogenic amines (BAs), important for human health. In this work, we tested 145 strains belonging to 12 different yeast species and isolated from the Colombian fermented cocoa beans (CB) for their capability of producing BAs in vitro. Sixtyfive strains were able to decarboxylate at least one of the amino acids tested. Pichia kudriavzevii ECA33 (Pk) and Saccharomyces cerevisiae 4 (Sc) were selected to evaluate their potential to modulate BAs, organic acids, and volatile organic compounds (VOCs) accumulation during a simulated cocoa fermentation. The growth of Sc or Pk in the presence of CB caused a significant reduction (p < 0.05) of 2-phenylethylamine (84% and 37%) and cadaverine (58% and 51%), and a significant increase of tryptamine and putrescine with a strong influence of temperature in BA formation and degradation. In addition, our findings pointed out that Pk induced a major production of fatty acidand amino acid-derived VOCs, while Sc induced more VOCs derived from fatty acids metabolism. Our results suggest the importance of considering BA production in the choice of yeast starters for cocoa fermentation

Selected topics on Hadrons in Nuclei

In this talk we report on selected topics on hadrons in nuclei. The first topic is the renormalization of the width of the $\Lambda(1520)$ in a nuclear medium. This is followed by a short update of the situation of the $\omega$ in the medium. The investigation of the properties of $\bar{K}$ in the nuclear medium from the study of the $(K_{flight},p)$ reaction is also addressed, as well as properties of X,Y,Z charmed and hidden charm resonances in a nuclear medium. Finally we address the novel issue of multimeson states.Comment: Talk at the International Nuclear Physics Conference, Vancouver, July 201

Differential Role of Human Choline Kinase α and β Enzymes in Lipid Metabolism: Implications in Cancer Onset and Treatment

11 pages, 6 figures, 1 table.Background The Kennedy pathway generates phosphocoline and phosphoethanolamine through its two branches. Choline Kinase (ChoK) is the first enzyme of the Kennedy branch of synthesis of 1phosphocholine, the major component of the plasma membrane. ChoK family of proteins is composed by ChoKα and ChoKβ isoforms, the first one with two different variants of splicing. Recently ChoKα has been implicated in the carcinogenic process, since it is over-expressed in a variety of human cancers. However, no evidence for a role of ChoKβ in carcinogenesis has been reported. Methodology/Principal Findings Here we compare the in vitro and in vivo properties of ChoKα1 and ChoKβ in lipid metabolism, and their potential role in carcinogenesis. Both ChoKα1 and ChoKβ showed choline and ethanolamine kinase activities when assayed in cell extracts, though with different affinity for their substrates. However, they behave differentially when overexpressed in whole cells. Whereas ChoKβ display an ethanolamine kinase role, ChoKα1 present a dual choline/ethanolamine kinase role, suggesting the involvement of each ChoK isoform in distinct biochemical pathways under in vivo conditions. In addition, while overexpression of ChoKα1 is oncogenic when overexpressed in HEK293T or MDCK cells, ChoKβ overexpression is not sufficient to induce in vitro cell transformation nor in vivo tumor growth. Furthermore, a significant upregulation of ChoKα1 mRNA levels in a panel of breast and lung cancer cell lines was found, but no changes in ChoKβ mRNA levels were observed. Finally, MN58b, a previously described potent inhibitor of ChoK with in vivo antitumoral activity, shows more than 20-fold higher efficiency towards ChoKα1 than ChoKβ. Conclusion/Significance This study represents the first evidence of the distinct metabolic role of ChoKα and ChoKβ isoforms, suggesting different physiological roles and implications in human carcinogenesis. These findings constitute a step forward in the design of an antitumoral strategy based on ChoK inhibition.This work has been supported by grants to JCL from Comunidad de Madrid (GR-SAL-0821-2004), Ministerio de Ciencia e Innovación (SAF2008-03750, RD06/0020/0016), Fundación Mutua Madrileña, and by a grant to ARM from Fundación Mutua Madrileña.Peer reviewe