Naloxone inhibits nicotine-induced receptor current and catecholamine secretion in bovine chromaffin cells

Nicotine-induced catecholamine (CA) secretion and inward ionic currents were inhibited by the opioid antagonist naloxone in cultured bovine chromaffin cells. Naloxone inhibited nicotine-induced CA secretion, as detected by an on-line real-time electrochemical technique, in a dose-dependent manner (IC50=29 [mu]M). In voltage-clamped chromaffin cells, nicotine (10 [mu]M) evoked an average peak inward current of -146 pA that was inhibited by low concentrations of naloxone (42% at 0.1 [mu]M). The antagonist also inhibited total charge influx associated with nicotinic receptor activation (53% at 0.1 [mu]M). This provides strong evidence that naloxone modulation of nicotine-induced CA secretion does not involve opioid receptors but results from the direct interaction with the nicotinic receptor itself, which might also be the case for other related opioid compounds.http://www.sciencedirect.com/science/article/B6SYR-43MC9YT-C/1/1994796a9d2862757ab52186bcacc5f

Numerical and experimental development of cupronickel filler brazed joints for divertor and first wall components in DEMO fusion reactor

The brazeability of a cupronickel commercial alloy (Cu10Ni) was evaluated for its use as a filler alloy for high- temperature joining of tungsten to the reduced activation ferritic/martensitic steel EUROFER 97 (W-E) and between tungsten base materials (W-W) for its application at the first wall and divertor of future fusion reactors. In addition, given the importance of the residual stresses in these heterogenous joints, a study of the brazing conditions and the impact of the selected filler has been conducted using numerical software to understand its impact on the quality of the joint. Two thermal cycles were evaluated (1165 $^◦$C and 1190$^◦$C) and selected based on the thermal characterization of the filler alloy. The microstructural examination revealed that, in W-E joints, nickel acts as an activator element, reacting and forming interfacial layers at the EUROFER 97 - Cu10Ni interface. In the case of the W-W joints, a lower level of diffusion phenomenon and metallurgical interaction between Cu10Ni and base materials were observed. The hardness profile indicated that the hardening process of EUROFER 97 was associated with the formation of untempered martensite. On the other hand, tungsten kept the received hardness. The me- chanical characterization by shear test reported similar values between both types of joints carried out at 1190$^◦$C but different when the temperature was increased (1165 $^°$C), associated with the brittle character of tungsten and its lower metallurgical interaction. The numerical analysis of the brazing process carried out with ANSYS software shows that residual stresses are accumulated mainly at the interfaces. The information provided by the simulation shows, for a 50 μm filler thickness, the importance of mitigating the residual stress by selecting a filler with an intermediate Coefficient of Thermal Expansion (CTE) that alleviates mechanical stresses relative to the base materials

In Vitro

Purpose. To evaluate the dose effect of vitamin K3 on wound healing mechanisms. Methods. Conjunctival fibroblasts were incubated for 24 hours. An artificial wound was made and the cells were incubated with fresh medium plus doses of vitamin K3 to be tested. Wound repair was monitored at 0, 18, 24, and 48 hours. Proliferation was measured in actively dividing cells by [3H]thymidine uptake. Six different groups were tested: group 1/no drugs added, group 2/ethanol 0.1%, group 3/vitamin K3 1 mg/L, group 4/vitamin K3 2 mg/L, group 5/vitamin K3 4 mg/L, and group 6/vitamin K3 6 mg/L. Each experiment was carried out in triplicate and 4 times. Results. There were no differences among groups at the initial time. In vitro wound repair was slower in groups 4, 5, and 6. There were no differences between control and ethanol groups and between control and vitamin K3 1 mg/L groups. Fibroblast mitogenic activity was statistically decreased in all vitamin K groups; statistical differences were found among vitamin K3 1 mg/mL and higher doses too. In groups 5 and 6, cellular toxicity was presented. Conclusions. Vitamin K3 is able to inhibit fibroblast proliferation. Vitamin K3 2 mg/L or higher doses inhibit wound healing repair, exhibiting cellular toxicity at 4 and 6 mg/L

Generación de una Línea Transgénica de Pez Cebra para Estudiar la Remodelación de Uniones Adherentes

El remodelado dinámico de los contactos adhesivos intercelulares o uniones adherentes (UAs) mediado por la proteína cadherina epitelial E (cadh-E) es clave para coordinar los movimientos migratorios celulares durante la embriogénesis animal. Debido a la simplicidad estructural y a la accesibilidad experimental, el embrión de pez cebra (Danio rerio) se ha establecido como un modelo para estudiar migración celular y para entender la dinámica del tráfico vesicular y distribución de cadh-E en UAs. En el presente proyecto se propuso generar una línea transgénica estable de pez cebra (cadh-E-KikGR) para la expresión de cadh-E fusionada a la proteína fotoconvertible KikGR para visualizar in vivo la remodelación de UAs. En una primera etapa se analizó la expresión endógena nativa de cadh-E y se comparó con la expresión transgénica de cadh-E fusionada a la proteína reportera fluorescente GFP (Green Fluorescent Protein) como una primera estrategia de monitoreo. Se observó que cadh-E no se localiza en membranas como la cadh-E endógena por lo que la fusión no sería funcional una vez expresada en el embrión. El clonado de KikGR, de menor tamaño, en reemplazo de GFP en el vector final de expresión permitirá la obtención del embrión transgénico de interés

Identification of animal species housed and herding practices in ancient sediments from the Vallone Inferno rock-shelter (Scillato, Sicily, Italy) using faecal biomarkers, hormones, and their metabolites

The interest in the identification of animal species housed in caves or rock-shelters used as livestock pen and herding management along prehistoric and historic ages, is increasing to understand better the development of pastoral activities. In this manuscript, a method for the quantification of β-sterol/phytosterols, bile acids, hormones and hormones metabolites has been developed to determine the main pastoral activities carried out in Vallone Inferno rock-shelter (Scillato, Sicily, Italy) from Middle Neolithic to Early Middle Age. According to the result obtained, the main animals housed in the rock-shelter went gradually changing from ovicaprids in Middle Neolithic to pigs in Early Middle Age. Additionally, new proxies (progesterone/Ʃbile acids and metabolites of progesterone/Ʃbile acids) were used to detect a high hormonal activity at Early Middle Age samples related with female pig management