Calibration and data extraction in a Stokes polarimeter employing three wavelengths simultaneously.

We present a method for calibration and data extraction for a Stokes polarimeter working with three different wavelengths simultaneously. In the Stokes polarimeter considered in this work, we use two liquid crystal variable retarders (LCVRs) combined with a Glan-Thompson linear polarizer. A recently developed fitting calibration procedure is used.

Functional expression of P2X1, P2X4 and P2X7 purinergic receptors in human monocyte-derived macrophages.

This study sought to examine the co-expression of the following purinergic receptor subunits: P2X1, P2X1del, P2X4, and P2X7 and characterize the P2X response in human monocyte-derived macrophages (MDMs). Single-cell RT-PCR shows the presence of P2X1, P2X1del, P2X4, and P2X7 mRNA in 40%, 5%, 20%, and 90% of human MDMs, respectively. Of the studied human MDMs, 25% co-expressed P2X1 and P2X7 mRNA; 5% co-expressed P2X4 and P2X7; and 15% co-expressed P2X1, P2X4, and P2X7 mRNA.

Characterization of the fluorescence intensity and color tonality in the exoskeleton of scorpions.

Scorpions are a mesodiverse and nocturnal group of arachnids inhabiting most biomes worldwide. Different species of scorpions have divergent adaptations to the substrate they live in, but most of them share an intriguing characteristic: their exoskeleton contains fluorophores that emit blue-greenish fluorescence under ultraviolet radiation. Although there are some reports in the literature on the study of fluorescence in scorpions, the biological functionality of this light emission is currently unknown and is under debate.

Physiological Concentrations of Zinc Have Dual Effects on P2X Myenteric Receptors of Guinea Pig.

We, hereby, characterize the pharmacological effects of physiological concentrations of Zinc on native myenteric P2X receptors from guinea-pig small intestine and on P2X2 isoforms present in most myenteric neurons. This is the first study describing opposite effects of Zinc on these P2X receptors. It was not possible to determine whether both effects were concentration dependent, yet the inhibitory effect was mediated by competitive antagonism and was concentration dependent.

Recreating Intestinal Peristalsis in the Petri Dish.

Here we describe a culture technique of cells dissociated from the external muscularis of the guinea pig small intestine, which allows us to maintain all the elements involved in the intestinal peristaltic reflex. After a few days in culture, these cells reorganize to form a small group of cells that permit the generation of pacemaker activity, spontaneous contractions, and the development of inhibitory and excitatory junction potentials in the petri dish, all elements involved in the peristaltic reflex. Therefore, these co-cultures are suitable to study the cellular and molecular aspects related to the development, maintenance, and modulation of motor intestinal functions.