The interactions of trialkyltin compounds with lysosomes from rat liver

Interactions of two trialkyltin compounds with the lysosomes from a rat liver have been studied. It is shown that these compounds induce a fast alkalinisation in the matrix of energised lysosomes. The fast alkalinisation rate is similar to the one obtained with uncouplers of the oxidative phosphorylation. An identical effect has been obtained with lysosomes energised in a chloride Free medium. This supports the hypothesis that trialkyltin compounds behave not only as Cl- /OH- exchangers, but also as proton carriers in biological membranes. This result could explain the toxicity and in particular the neurotoxicity of trialkyltin compound

A new procedure for the monitoring of cationic detergents in solution

The paper describes a new procedure for the selective monitoring of cationic surfactants in solution. The procedure is based on the fact that cationic surfactants are accumulated inside mitochondria by a potential-driven mechanism. Once inside, the surfactant induces the release of the dye Safranine, previously accumulated inside mitochondria. Therefore the monitoring consists of a direct spectrophotometric measure of the rate of release of safranine in the resuspending medium containing the cationic surfactant

The concerted action of the Helicobacter pylori cytotoxin VacA and of the v-ATPase proton pump induces swelling of isolated endosomes

The vacuolating cytotoxin (VacA) is a major virulence factor of Helicobacter pylori, the bacterium associated to gastroduodenal ulcers and stomach cancers. VacA induces formation of cellular vacuoles that originate from late endosomal compartments. VacA forms an anion-selective channel and its activity has been suggested to increase the osmotic pressure in the lumen of these acidic compartments, driving their swelling to vacuoles. Here, we have tested this proposal on isolated endosomes that allow one to manipulate at will the medium. We have found that VacA enhances the v-ATPase proton pump activity and the acidification of isolated endosomes in a Cl- dependent manner. Other counter-anions such as pyruvate, Br-, I- and SCN- can be transported by VacA with stimulation of the v-ATPase. The VacA action on isolated endosomes is associated with their increase in size. Single amino acid substituted VacA with no channel-forming and vacuolating activity is unable to induce swelling of endosomes. These data provide a direct evidence that the transmembrane VacA channel mediates an influx of anions into endosomes that stimulates the electrogenic v-ATPase proton pump, leading to their osmotic swelling and transformation into vacuoles

2019 Dataset of Participatory Budgeting in Italy

The dataset provides data on Italian Municipalities’ policies pertaining to participatory budgeting (PB). The dataset comprises information on municipalities with a population of over 2,000 inhabitants, and is composed as follows: Municipality ISTAT Code (ID), Municipality Name (MN) Province, Region, Population (2011 Census), Researcher (IR), Mapping randomized process (MR), Mapping Method (MM), twenty dummy variables identifying Municipalities running PB in a given year (y1994, y2002 to y2020), Number of years with PB (TOT). Overall, the dataset comprises 4517 units (with 467 missing), for a total of 4050 mapped municipalities