11 documents found, page 1 of 2
Multifunctionalization of cyanuric chloride for the stepwise synthesis of poten...
Calvete, Mário J. F.; Pinto, Sara M. A.; Burrows, Hugh D.; Castro, M. Margarida C. A.; Geraldes, Carlos F. G. C.; Pereira, Mariette M.We report a synthetic strategy to combine different moieties in a single structure using cyanuric chloride (2,4,6-trichlorotriazine) as a starting platform for preparing potential bioimaging agents. This reacted with macrocycles of the porphyrin family and DOTA type metal chelators through mono-, di- and tri- substitution of its chlorine atoms by appropriate nucleophiles, control- ling the stepwise by temperatu...
Dual Imaging Gold Nanoplatforms for Targeted Radiotheranostics
Silva, Francisco; Paulo, António; Pallier, Agnès; Même, Sandra; Tóth, Éva; Gano, Lurdes; Marques, Fernanda; Geraldes, Carlos F. G. C.Gold nanoparticles (AuNPs) are interesting for the design of new cancer theranostic tools, mainly due to their biocompatibility, easy molecular vectorization, and good biological half-life. Herein, we report a gold nanoparticle platform as a bimodal imaging probe, capable of coordinating Gd3+ for Magnetic Resonance Imaging (MRI) and 67Ga3+ for Single Photon Emission Computed Tomography (SPECT) imaging. Our AuNP...
The interaction between dopamine D2-like and beta-adrenergic receptors in the p...
Montezinho, Liliana P.; Castro, M. Margarida C. A.; Duarte, Carlos B.; Penschuck, Silke; Geraldes, Carlos F. G. C.; Mørk, ArneSeveral studies have suggested the involvement of biogenic monoaminergic neurotransmission in bipolar disorder and in the therapy for this disease. In this study, the effects of the mood-stabilizing drugs lithium, carbamazepine or valproate on the dopaminergic and adrenergic systems, particularly on D2-like and 03B2-adrenergic receptors, were studied both in cultured rat cortical neurones and in rat prefrontal ...
Crystal Structure of the VV Dimer [V2O2(μ-O)(dmpp)2(OCH3)2] and Its Equilibrium...
Avecilla, Fernando; Geraldes, Carlos F. G. C.; Macedo, Anjos L.; Castro, M. Margarida C. A.The behaviour of the cyclic trimeric VV complex [V3O3(μ-O)3(dmpp)3(H2O)](H2O)2, V3L3, (L = Hdmpp = 3-hydroxy-1,2-dimethyl-4-pyridinone) was studied in methanol and methanol/water solutions by using 51V and 1D- and 2D 1H NMR spectroscopy. Red crystals, isolated from a highly concentrated methanol solution of the trimeric complex, were analysed by X-ray crystallography. The solid-state structure of the compound s...
Uptake and metabolic effects of insulin mimetic oxovanadium compounds in human ...
Delgado, Teresa C.; Tomaz, A. Isabel; Correia, Isabel; Pessoa, João Costa; Jones, John G.; Geraldes, Carlos F. G. C.; Castro, M. Margarida C. A.The uptake of the oxidation products of two oxovanadium(IV) compounds, [N,N'-ethylenebis(pyridoxylaminato)]oxovanadium(IV), VIVO(Rpyr2en), and bis-[3-hydroxy-1,2-dimethyl-4-pyridinonato]oxovanadium(IV), VIVO(dmpp)2, by human erythrocytes was studied using 51V and 1H NMR and EPR spectroscopy. VIVO(Rpyr2en) in aerobic aqueous solution is oxidized to its VV counterpart and the neutral form slowly enters the cells ...
Vanadium(IV and V) Complexes of Schiff Bases and Reduced Schiff Bases Derived f...
Correia, Isabel; Pessoa, João Costa; Duarte, M. Teresa; Piedade, M. Fátima Minas da; Jackush, Tamás; Kiss, Tamás; Castro, M. Margarida C. A.Several sal2en-type reduced Schiff bases have been prepared from the reaction of 2 equiv. of salicylaldehyde (or derivatives) with ethylenediamine followed by reduction with NaBH4 and subsequently characterised. The water-soluble ligands (SO3-sal)2en and R(SO3-sal)2en (SO3-sal = salicylaldehyde-5-sulphonate) have been studied by pH potentiometry and 1H NMR spectroscopy and the protonation constants of R(SO3-sal...
Melamine/epichlorohydrin prepolymers: syntheses and characterization
Pedroso, Luís M.; Castro, M. Margarida C. A.; Simões, Pedro; Portugal, AntónioThe basic catalysis of melamine with epichlorohydrin gives prepolymers that can be used in the preparation of energetic materials. In this work, sodium hydroxide and triethylamine were used as catalysts and ethyleneglycol as initiator. Different reaction conditions were tested and the characterization of the products was carried out by IR and NMR spectroscopy and MS spectrometry, hydroxyl groups content, vapour...
N,N'-Ethylenebis(pyridoxylideneiminato) and N,N'-Ethylenebis(pyridoxylaminato):...
Correia, Isabel; Pessoa, João Costa; Duarte, M. Teresa; Henriques, Rui T.; Piedade, M. Fátima M.; Veiros, Luís F.; Jakusch, Tamás; Kiss, TamásThe Schiff base N,Nprime-ethylenebis(pyridoxylideneiminato) (H2pyr2en, 1) was synthesized by reaction of pyridoxal with ethylenediamine; reduction of H2pyr2en with NaBH4 yielded the reduced Schiff base N,Nprime-ethylenebis(pyridoxylaminato) (H2Rpyr2en, 2); their crystal structures were determined by X-ray diffraction. The totally protonated forms of 1 and 2 correspond to H6L4+, and all protonation constants wer...
Quantification and Localization of Intracellular Free Mg2+ in Bovine Chromaffin...
Montezinho, Liliana P.; Fonseca, Carla P.; Geraldes, Carlos F. G. C.; Castro, M. Margarida C. A.Magnesium is an essential element for all living systems. The quantification of free intracellular Mg(2+) concentration ([Mg(2+)](i)) is of utmost importance since changes in its basal value may be an indication of different pathologies due to abnormalities of Mg(2+) metabolism. In this work we used (31)P NMR and fluorescence spectroscopy to determine the resting [Mg(2+)](i) in bovine chromaffin cells, a neuron...
Li influx and binding, and li/mg competition in bovine chromaffin cell suspensi...
Fonseca, Carlos P.; Montezinho, Liliana P.; Baltazar, Graça; Layden, Brian; Freitas, Duarte M.; Geraldes, Carlos F. G. C.; Castro, M. Margarida C. A.Li(+) influx by bovine chromaffin cells, obtained from bovine adrenal medulla, was studied in intact cell suspensions using (7)Li NMR spectroscopy with the shift reagent [Tm(HDOTP)](4-). The influx rate constants, k(i), were determined in the absence and in the presence of two Na(+) membrane transport inhibitors. The values obtained indicate that both voltage sensitive Na(+) channels and (Na(+)/K(+))-ATPase pla...