Interaction between cannabis consumption and childhood abuse in psychotic disorders:preliminary findings on the role of different patterns of cannabis use

Aim: Several studies have suggested that lifetime cannabis consumption and childhood abuse synergistically contribute to the risk for psychotic disorders. This study aimed to extend existing findings regarding an additive interaction between childhood abuse and lifetime cannabis use by investigating the moderating role of type and frequency of cannabis use. Methods: Up to 231 individuals presenting for the first time to mental health services with psychotic disorders and 214 unaffected population controls from South London, United Kingdom, were recruited as part of the Genetics and Psychosis study. Information about history of cannabis use was collected using the Cannabis Experiences Questionnaire. Childhood physical and sexual abuse was assessed using the Childhood Experience of Care and Abuse Questionnaire. Results: Neither lifetime cannabis use nor reported exposure to childhood abuse was associated with psychotic disorder when the other environmental variable was taken into account. Although the combination of the two risk factors raised the odds for psychosis by nearly three times (adjusted OR = 2.94, 95% CI: 1.44–6.02, P = 0.003), no evidence of interaction was found (adjusted OR = 1.46, 95% CI: −0.54 to 3.46, P = 0.152). Furthermore, the association of high-potency cannabis and daily consumption with psychosis was at least partially independent of the effect of childhood abuse. Conclusions: The heavy use of high-potency cannabis increases the risk of psychosis but, in addition, smoking of traditional resin (hash) and less than daily cannabis use may increase the risk for psychosis when combined with exposure to severe childhood abuse.</p

INHOMOGENITEIT GEBASEERDE ANALYSE VAN DE VERDELING VAN PLASMA MEMBRAAN COMPONENTEN

status: publishe

Analyzing protein clusters on the plasma membrane: application of spatial statistical analyses on super-resolution microscopy images

The spatial distribution of proteins within the cell affects their capability to interact with other molecules and directly influences cellular processes and signaling. At the plasma membrane, multiple factors drive protein compartmentalization into specialized functional domains, leading to the formation of clusters in which intermolecule interactions are facilitated. Therefore, quantifying protein distributions is a necessity for understanding their regulation and function. The recent advent of super-resolution microscopy has opened up the possibility of imaging protein distributions at the nanometer scale. In parallel, new spatial analysis methods have been developed to quantify distribution patterns in super-resolution images. In this chapter, we provide an overview of super-resolution microscopy and summarize the factors influencing protein arrangements on the plasma membrane. Finally, we highlight methods for analyzing clusterization of plasma membrane proteins, including examples of their applications.status: publishe

Reply to Vanacore and Galeotti: Sequential trials and the use of placebo

No abstract availabl

Lithium in ALS: from the bench to the bedside

No abstract availabl

Inhomogeneity Based Characterization of Distribution Patterns on the Plasma Membrane

Cell surface protein and lipid molecules are organized in various patterns: randomly, along gradients, or clustered when segregated into discrete micro- and nano-domains. Their distribution is tightly coupled to events such as polarization, endocytosis, and intracellular signaling, but challenging to quantify using traditional techniques. Here we present a novel approach to quantify the distribution of plasma membrane proteins and lipids. This approach describes spatial patterns in degrees of inhomogeneity and incorporates an intensity-based correction to analyze images with a wide range of resolutions; we have termed it Quantitative Analysis of the Spatial distributions in Images using Mosaic segmentation and Dual parameter Optimization in Histograms (QuASIMoDOH). We tested its applicability using simulated microscopy images and images acquired by widefield microscopy, total internal reflection microscopy, structured illumination microscopy, and photoactivated localization microscopy. We validated QuASIMoDOH, successfully quantifying the distribution of protein and lipid molecules detected with several labeling techniques, in different cell model systems. We also used this method to characterize the reorganization of cell surface lipids in response to disrupted endosomal trafficking and to detect dynamic changes in the global and local organization of epidermal growth factor receptors across the cell surface. Our findings demonstrate that QuASIMoDOH can be used to assess protein and lipid patterns, quantifying distribution changes and spatial reorganization at the cell surface. An ImageJ/Fiji plugin of this analysis tool is provided.status: publishe

Ultrafast geminate electron-radical recombination dynamics in photoactive yellow protein

Photoinduced ionization of the chromophore inside photoactive yellow protein (PYP) was investigated by ultrafast spectroscopy in the visible-near infrared spectral region. A solvated electron absorption-like band was observed that extended from around 550nm to 850nm, centred at 700nm. Simulation of the decay traces of the band with a classic diffusion model indicated that ejected electrons were located an average distance of ~3Å away from the radical centre, and around 40% the solvated electrons were annihilated by geminate recombination. The remaining 60% escaped out of the protein pocket to be annihilated by bulk recombination. This result indicates that the chromophore is in a local environment inside PYP that is only slightly different from the bath solvent

Ultrafast geminate electron-radical recombination dynamics in photoactive yellow protein

Photoinduced ionization of the chromophore inside photoactive yellow protein (PYP) was investigated by ultrafast spectroscopy in the visible-near infrared spectral region. A solvated electron absorption-like band was observed that extended from around 550nm to 850nm, centred at 700nm. Simulation of the decay traces of the band with a classic diffusion model indicated that ejected electrons were located an average distance of ~3Å away from the radical centre, and around 40% the solvated electrons were annihilated by geminate recombination. The remaining 60% escaped out of the protein pocket to be annihilated by bulk recombination. This result indicates that the chromophore is in a local environment inside PYP that is only slightly different from the bath solvent

Inhomogeneity Based Characterization of Distribution Patterns on the Plasma Membrane

<div><p>Cell surface protein and lipid molecules are organized in various patterns: randomly, along gradients, or clustered when segregated into discrete micro- and nano-domains. Their distribution is tightly coupled to events such as polarization, endocytosis, and intracellular signaling, but challenging to quantify using traditional techniques. Here we present a novel approach to quantify the distribution of plasma membrane proteins and lipids. This approach describes spatial patterns in degrees of inhomogeneity and incorporates an intensity-based correction to analyze images with a wide range of resolutions; we have termed it <b>Qu</b>antitative <b>A</b>nalysis of the <b>S</b>patial distributions in <b>I</b>mages using <b>Mo</b>saic segmentation and <b>D</b>ual parameter <b>O</b>ptimization in <b>H</b>istograms (QuASIMoDOH). We tested its applicability using simulated microscopy images and images acquired by widefield microscopy, total internal reflection microscopy, structured illumination microscopy, and photoactivated localization microscopy. We validated QuASIMoDOH, successfully quantifying the distribution of protein and lipid molecules detected with several labeling techniques, in different cell model systems. We also used this method to characterize the reorganization of cell surface lipids in response to disrupted endosomal trafficking and to detect dynamic changes in the global and local organization of epidermal growth factor receptors across the cell surface. Our findings demonstrate that QuASIMoDOH can be used to assess protein and lipid patterns, quantifying distribution changes and spatial reorganization at the cell surface. An ImageJ/Fiji plugin of this analysis tool is provided.</p></div