Search results for "TRP"
showing 10 items of 102 documents
The cAMP Pathway Sensitizes VR1 Expressed in Oocytes from <i>Xenopus laevis</i> and in CHO Cells
2003
The vanilloid receptor 1 (VR1) is a heat-activated cation channel which also responds to capsaicin and other chemical stimuli. Protein kinase C has a stimulatory effect on VR1 activity, either alone or after activation with capsaicin. The influence of the cAMP-signaling pathway on the effects of capsaicin is controversial. To clarify this, the actions of capsaicin and the modulatory effects of forskolin, pCPT-cAMP, and isobutylmethylxanthine were studied in <i>Xenopus laevis</i> oocytes expressing rat VR1 and in CHO cells expressing human VR1. Capsaicin activated the VR1 channel and increased the intracellular calcium concentration. The effects of capsaicin were enhanced by fors…
New copolymers graft of α,β-poly(N-2-hydroxyethyl)-d,l-aspartamide obtained from atom transfer radical polymerization as vector for gene delivery
2012
Abstract New cationic α,β-poly(N-2-hydroxyethyl)- d , l -aspartamide (PHEA) graft copolymers were synthesized by ATRP, using diethylamino ethyl methacrylate (DEAEMA) as monomer for polymerization, yielding polycations (PHEA-pDEAEMA) able to condense DNA. Then, consecutive ATRP conditions were set up on PHEA-pDEAEMA to obtain copolymers containing also hydrophilic chains (PHEA-IB-pDMAEMA-pPEGMA) able to improve biocompatibility of polyplexes and to provide them stealth properties. Agarose gel studies showed that the copolymers effectively condensed plasmid DNA to form polyplexes. Light scattering studies were used to analyze the size and the ζ -potential of these polyplexes, showing that cop…
Utilization of Poly(vinylchloride) and Poly(vinylidenefluoride) as Macroinitiators for ATRP Polymerization of Hydroxyethylmethacrylate. Electroanalyt…
2015
The utilization of poly(vinylchloride) (PVC) and poly(vinylidenefluoride) (PVDF) as macroinitiators for atom transfer radical polymerization (ATRP) of hydroxyethylmethacrylate (HEMA) was studied performing electroanalytical investigations and “grafting from” experiments in order to achieve information on the possibility of modifying such commercial polymers by this controlled free radical polymerization technique. This study was performed changing various operating parameters such as the nature of the copper salt, the ligand, the solvent, the temperature and the reaction time. Electroanalytical data suggest that PVC can be easily activated by both CuCl/ Tris(2-pyridylmethyl)amine (TPMA) and…
Atom transfer radical polymerization with different halides (F, Cl, Br, and I): Is the process "living" in the presence of fluorinated initiators?
2016
Atom transfer radical polymerization (ATRP) is often used for grafting from fluorinated polymers. Nevertheless, the possibility to initiate an ATRP from a C-F functionality and the activity of the catalysts in the presence of fluoride anions are essentially unexplored. Therefore, we investigated the thermodynamics and kinetics of C-F bond activation by ATRP catalysts and compared it with other halide systems. The ATRP equilibrium constant was estimated to be small for the reaction between [CuITPMA]+ and benzyl fluoride (TPMA = tris(2-pyridylmethyl)- amine). However, [CuITPMA] + could react with the more active initiator diethyl fluoromalonate (DEFM). With DEFM as initiator and CuIBr/TPMA as…
Synthesis of Novel Folic Acid-Functionalized Biocompatible Block Copolymers by Atom Transfer Radical Polymerization for Gene Delivery and Encapsulati…
2005
Two synthetic routes to folic acid (FA)-functionalized diblock copolymers based on 2-(methacryloyloxy)- ethyl phosphorylcholine [MPC] and either 2-(dimethylamino)ethyl methacrylate [DMA] or 2-(diisopropylamino) ethyl methacrylate [DPA] were explored. The most successful route involved atom transfer radical polymerization (ATRP) of MPC followed by the tertiary amine methacrylate using a 9-fluorenylmethyl chloroformate (Fmoc)-protected ATRP initiator. Deprotection of the Fmoc groups produced terminal primary amine groups, which were conjugated with FA to produce two series of novel FA-functionalized biocompatible block copolymers. Nonfunctionalized MPC-DMA diblock copolymers have been previou…
TrpM, a Small Protein Modulating Tryptophan Biosynthesis and Morpho-Physiological Differentiation in Streptomyces coelicolor A3(2).
2016
In the model actinomycete Streptomyces coelicolor A3(2), small open reading frames encoding proteins with unknown functions were identified in several amino acid biosynthetic gene operons, such as SCO2038 (trpX) in the tryptophan trpCXBA locus. In this study, the role of the corresponding protein in tryptophan biosynthesis was investigated by combining phenotypic and molecular analyses. The 2038KO mutant strain was characterized by delayed growth, smaller aerial hyphae and reduced production of spores and actinorhodin antibiotic, with respect to the WT strain. The capability of this mutant to grow on minimal medium was rescued by tryptophan and tryptophan precursor (serine and/or indole) su…
TRPV1 channels in nitric oxide-mediated signalling: insight on excitatory transmission in rat CA1 pyramidal neurons
2022
Nitric oxide (NO) is a fascinating signalling molecule implicated in a plethora of biological functions, especially at the synaptic level. Exploring neurotransmission in the hippocampus could be instrumental in the individuation of putative targets for nitric-oxide mediated neuromodulation, especially in terms of the potential repercussions on fundamental processes i.e. synaptic plasticity and excitability-related phenomena. Among these targets, endovanilloid signalling constitutes an object of study since Transient Receptors Vanilloid type 1 (TRPV1) channels possess a NO-sensitive gate modulating its activation. Also, NO has been referred to as a mediator for numerous endocannabinoid effec…
Kontrpropaganda PSRS kinomākslā 1970. un 1980. gados: Rīgas kinostudijas mākslas filmas par Rietumu sabiedrību
2016
Aptuveni desmit gadu laikā — no 1970. gadu vidus līdz 1980. gadu vidum — Rīgas kinostudijā tika uzņemta virkne specifisku kriminālfilmu — tās bija vairākas televīzijas mākslas filmas, kuru darbība pilnībā norisinās "kapitālistiskajos Rietumos" un kuras vieno kopīgas pazīmes, kas nav raksturīgas citām padomju kinofilmām. Maģistra darba mērķis ir noskaidrot šo filmu tapšanas īpatnības un to, kā pētāmo filmu veidošanas kontekstā izpaudies padomju kontrpropagandas aspekts. Darbā tiek rekonstruēta piecu kontrpropagandas filmu tapšanas gaita, īpašu uzmanību pievēršot ideoloģiskās funkcijas integrēšanas procesam. Pētījumā secināts, ka mākslas filmas par Rietumu sabiedrību bija savdabīga Aukstā kar…