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During cell invasion, large Extracellular Vesicle (lEV) release from host cells was dose-dependently triggered by Trypanosoma cruzi metacyclic trypomastigotes (Mtr). This lEV release was inhibited when IP 3 -mediated Ca 2+ exit from the ER and further Ca 2+ entry from plasma membrane channels was blocked, but whilst any store-independent Ca 2+ entry (SICE) could continue unabated. That lEV release was equally inhibited if all entry from external sources was blocked by chelation of external Ca 2+ points to the major contributor to Mtr-triggered host cell lEV release being IP 3 /store-mediated Ca 2+ release, SICE playing a minor role. Host cell lEVs were released through Mtr interaction with host cell lipid raft domains, integrins, and mechanosensitive ion channels, whereupon [Ca 2+ ] cyt increased (50 to 750 nM) within 15 s. lEV release and cell entry of T. cruzi, which increased up to 30 and 60 mpi, respectively, as well as raised actin depolymerization at 60 mpi, were all reduced by TRPC inhibitor, GsMTx-4. Vesicle release and infection was also reduced with RGD peptide, methyl-β-cyclodextrin, knockdown of calpain and with the calpain inhibitor, calpeptin. Restoration of lEV levels, whether with lEVs from infected or uninfected epithelial cells, did not restore invasion, but supplementation with lEVs from infected monocytes, did. We provide evidence of THP-1 monocyte-derived lEV interaction with Mtr (lipid mixing by R18-dequenching; flow cytometry showing transfer to Mtr of R18 from R18-lEVs and of LAP(TGF-β1). Active, mature TGF-β1 (at 175 pg/×10 5 in THP-1 lEVs) was detected in concentrated lEV-/cell-free supernatant by western blotting, only after THP-1 lEVs had interacted with Mtr. The TGF-β1 receptor (TβRI) inhibitor, SB-431542, reduced the enhanced cellular invasion due to monocyte-lEVs., (© 2024 The Author(s). Journal of Extracellular Vesicles published by Wiley Periodicals LLC on behalf of International Society for Extracellular Vesicles.)

Extracellular vesicles (EVs) include a heterogeneous group of particles. Microvesicles, apoptotic bodies and exosomes are the most characterized vesicles. They can be distinguished by their size, morphology, origin and molecular composition. To date, increasing studies demonstrate that EVs mediate intercellular communication. EVs reach considerable interest in the scientific community due to their role in diverse processes including antigen-presentation, stimulation of anti-tumoral immune responses, tolerogenic or inflammatory effects. In pathogens, EV shedding is well described in fungi, bacteria, protozoan and helminths parasites. For Trypanosoma cruzi EV liberation and protein composition was previously described. Dendritic cells (DCs), among other cells, are key players promoting the immune response against pathogens and also maintaining self-tolerance. In previous reports we have demonstrate that T. cruzi downregulates DCs immunogenicity in vitro and in vivo . Here we analyze EVs from the in vitro interaction between blood circulating trypomastigotes (Tp) and bone-marrow-derived DCs. We found that Tp incremented the number and the size of EVs in cultures with DCs. EVs displayed some exosome markers and intracellular RNA. Protein analysis demonstrated that the parasite changes the DC protein-EV profile. We observed that EVs from the interaction of Tp-DCs were easily captured by unstimulated-DCs in comparison with EVs from DCs cultured without the parasite, and also modified the activation status of LPS-stimulated DCs. Noteworthy, we found protection in animals treated with EVs-DCs+Tp and challenged with T. cruzi lethal infection. Our goal is to go deep into the molecular characterization of EVs from the DCs-Tp interaction, in order to identify mediators for therapeutic purposes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gutierrez, Ancarola, Volpato-Rossi, Marcilla, Ramirez, Rosenzvit, Cucher and Poncini.)

The smoke exposure hazards during combustion of carbon and nitrogen-containing fibers were evaluated in guinea pigs intoxicated by gradual exposure to HCN and CO neo-formed from foam rubber, wool and PAN (Polyacrylonitrile). The most prominent result of our study was that the neo-formation of HCN from 1 g of PAN was 1500 ppm, much higher than from foam rubber and wool because of the presence of many -CN groups in the polymer chemical structure. This concentration of HCN is estimated to be lethal. Extrapolating this data, a lethal concentration of HCN could be obtained by burning 2 kg of PAN in an average sized living room. The above-mentioned 1 g of PAN was burned in a 15.6-liter combustion chamber.

A series of carboxamides of benzotiopyranopyrazoles and benzothiiopyranoisoxazoles was synthesized starting from benzothiopyran-4-one-3-methylglyoxylates through two synthetic methods and tested for anti-inflammatory, analgesic and cardiovascular activity. Some of these compounds display pronounced antiarrhythmic activity.

The anti-inflammatory, analgesic and antipyretic effects and the tolerability of 2-(4-isobutylphenyl)-propionic acid (ibuprofen) were compared with those of its derivative 2-(4-isobutylphenyl)-propiohydroxamic acid (ibuproxam, Ibudros. Our experiments show that the interfering action of the two drugs with the reactive processes of the tibio-tarsic articulation, brought about by carrageenin, serotonin, dextrane and formalin is of the same intensity. Also, the analgesic activity is perfectly consistent with the antipyretic one. However, the tolerability of the two molecules is different; the acute toxicity is consistent in the case of the single parenteral administration and it differs in the case of a single or repeated oral treatment. When used under these conditions, ibuproxam is considerably less damaging to the gastroenteric tube than is ibuprofen. The hypothesis is put forth that the greater tolerability of ibuproxam is due to its pharmacokinetics: it is, as such, little or not toxic for the mucous membrane of the digestive apparatus, and it progressively releases ibuprofen, whose concentrations in the blood would remain below those levels that cause systemic lesions in the gastroenteric tract.

A series of quaternary salts of aminoethyl-p-aminobenzoates and aminoethyl-p-aminobenzamides was synthesized starting from 4-hydroxy-3-carbomethoxy benzoic acid. Pharmacological tests of these compounds show significant spasmolytic activity: in a few cases this was also selective, but at the same time bioavailability was low.

By studying the influence of the arginine pyroglutamate on the CNS its variations were evidenced which are clearly identifiable through the analysis of the interaction with molecules having either a depressive or excitatory action. In the case of pentobarbital the antagonistic effect of the compound on the general anaesthesia is very intense and is equally present even when medazepam and flurazepam are associated. Equally obvious is the antagonism with barbiturate in the case of spontaneous motility but much less so with the two benzodiazepines. As far as the specialized behaviour is concerned, arginine pyroglutamate does not alter the sound discrimination capacity (responses in Sdelta punished) at fixed intervals (F.I.) nor does it influence the learning of a sound discrimination (responses in Sdelta punished) at varied intervals (V.I.). The process of learning is instead moderately accelerated in the case of a temporal discrimination and of a conditioned avoidance response (CAR) in the shuttle-box. No effect was found when the same amino acids were introduced alone or in random association. The hypothesis is proposed that the phenomena described depend on the different pharmacokinetics of arginine pyroglutamate that ensures brain concentrations sufficient to block the activity of depressive compounds but is not capable of influencing in a significant way the spontaneous and specialized behaviour of normal animals.

The metabolism of 2-(4-isobutylphenyl)-propio-hydroxamic acid (ibuproxam, Ibudros), a new molecule with anti-inflammatory, antipyretic and analgesic activity was studied by its administration orally and rectally to the rat. The analysis, carried out with gas chromatographic method and thin-layer chromatography, showed that the drug is present in blood as 2-(4-isobutylphenyl)-propionic acid (ibuprofen), an anti-inflammatory drug which is commonly used and the metabolites of which are already known. Using the same methods, it was observed that only a few traces of the hydroxamic acid appear in the urines of rats treated with ibuproxam, whilst the ibuprofen metabolite is absent. Therefore, we conclude that the drug ibuproxam changes rapidly into ibuprofen, following afterwards the same known metabolic process as the latter drug.