Characterization of PLGA microparticles as a drug carrier for 3-ethoxycarbonyl-2H-benzofuro[3,2-f]-1-benzopyran-2-one. Ultrastructural study of cellular uptake and intracellular distribution

Here we describe the application of microparticles (MPs) for the delivery and release of the drug a benzopsoralen. We also evaluated the intracellular distribution and cellular uptake of the drug by using an encapsulation technique for therapeutic optimization. MPs containing the compound 3-ethoxycarbonyl-2H-benzofuro[3,2-f]-1-benzopyran-2-one (psoralen A) were prepared by the solvent evaporation technique, and parameters such as particle size, drug encapsulation efficiency, effect of the encapsulation process on the drug's photochemistry, zeta potential, external morphology, and < i > in vitro release behavior were evaluated. The intracellular distribution of MPs as well as their uptake by tissues were monitored. Size distribution studies using dynamic ligh scattering and scanning electron microscopy revealed that the MPs are spherical in shape with a diameter of 1.4 mu m. They present low tendency toward aggregation, as confirmed by their zeta potential (+10.6 mV). The loading efficiency obtained was 75%. As a consequence of the extremely low diffusivity of the drug in aqueous medium, the drug release profile of the MPs in saline phosphate buffer (pH 7.4) was much slower than that obtained in the biological environment. Among the population of peritoneal phagocytic cells, only macrophages were able to phagocytose poly-d,l-lactic-co-glycolic acid (PLGA) MP. The use of psoralen A in association with ultraviolet light (360 nm) revealed morphological characteristics of cell damage such as cytoplasmic vesiculation, mitochondria condensation, and swelling of both the granular endoplasmatic reticulum and the nuclear membrane. These results indicate that PLGA MP could be a promising delivery system for psoralen in connection with ultraviolet irradiation therapy (PUVA).

Constraints on spin-3/2 and excited spin-1/2 fermions coming from the leptonic Z0-partial width

We consider effective interactions among excited spin-1/2 and spin-3/2 leptons with the usual ones. Assuming that these new leptons are lighter than the Z0, we study the constraints on their masses and compositeness scale coming from the leptonic Z0 partial width.

Superstrings in graviphoton background and N = 1/2 + 3/2 supersymmetry

Motivated by Ooguri and Vafa, we study superstrings in flat ℝ4 in a constant self-dual graviphoton background. The supergravity equations of motion are satisfied in this background which deforms the M = 2 d = 4 flat space super-Poincaré algebra to another algebra with eight supercharges. A D-brane in this space preserves a quarter of the supercharges; i.e. N = 1/2 supersymmetry is realized linearly, and the remaining N = 3/2 supersymmetry is realized nonlinearly. The theory on the brane can be described as a theory in noncommutative superspace in which the chiral fermionic coordinates θα of N = 1 d = 4 superspace are not Grassman variables but satisfy a Clifford algebra. © SISSA/ISAS 2003.

Adsorção dos íons cobre, cobalto e níquel na superfície organofuncionalizada 3(2-Amino-1,3,4-Tiadiazol) sílica gel, ATDSG

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Teorias duais massivas de spin-3 em D=2+1: Elias Leite Mendonça. -

Pós-graduação em Física - FEG

Magnetocrystalline interactions and oxidation state determination of Mn(2-x)V(1+x)O4 (x=0, 1/3 and 1) magnetorresistive spinel family

Oxidation states of transition metal cations in spinels-type oxides are sometimes extremely difficult to determine by conventional spectroscopic methods. One of the most complex cases occurs when there are different cations, each one with several possible oxidation states, as in the case of the magnetoresistant Mn(2-x)V(1+x)O4 (x=0, 1/3 and 1) spinel-type family. In this contribution we describe the determination of the oxidation state of manganese and vanadium in Mn(2-x)V(1+x)O4 (x=0, 1/3,1) spinel-type compounds by analyzing XANES and high-resolution K beta X-ray fluorescence spectra. The ionic models found are Mn22+V4+O4, Mn5/32+V4/33.5+O4 and Mn2+V23+O4. Combination of the present results with previous data provided a reliable cation distribution model. For these spinels, single magnetic electron paramagnetic resonance (EPR) lines are observed at 480 K showing the interaction among the different magnetic ions. The analysis of the EPR parameters show that g-values and relative intensities are highly influenced by the concentration and the high-spin state of Mn2+. EPR broadening linewidth is explained in terms of the bottleneck effect, which is due to the presence of the fast relaxing V3+ ion instead of the weak Mn2+ (S state) coupled to the lattice. The EPR results, at high temperature, are well explained assuming the oxidation states of the magnetic ions obtained by the other spectroscopic techniques. (c) 2013 Elsevier Inc. All rights reserved.

Efeitos da injeção de 3 amino 1,2,4 triazole (ATZ), inibidor da catalase, na área septal medial na ingestão de água e na excreção renal de água e eletrólitos induzidos pela estimulação colinérgica também da área septal medial

A área septal medial (ASM), situada no prosencéfalo, está envolvida na regulação cardiovascular e no controle do balanço hidroeletrolítico. Esta área é rica em receptores colinérgicos e a ativação dos mesmos induz ingestão de água, natriurese e anti-diurese. Existem evidências experimentais de que as espécies reativas de oxigênio possam participar do controle de respostas fisiológicas. Resultados recentes de nosso laboratório demonstraram que uma espécie reativa de oxigênio, o peróxido de hidrogênio (H2O2), injetada na ASM reduz a ingestão de água induzida por carbacol (agonista colinérgico) também injetado na ASM. No presente projeto propomos estudar os efeitos do aumento da produção endógena de H2O2 na ASM nos efeitos dipsogênico, natriurético e anti-diurético do carbacol injetado na ASM. O inibidor da catalase, 3 amino 1,2,4 triazole (ATZ) será injetado na ASM para aumentar os níveis endógenos de H2O2

N-Methyl-2-(1-methyl-3-phenyl­prop-2-en-1-yl­idene)hydrazinecarbo­thio­amide

In the title compound, C12H15N3S, the mol­ecule deviates slightly from planarity, with a maximum deviation from the mean plane of the non-H atoms of 0.2756 (6) Å for the S atom and a torsion angle for the N-N-C-N fragment of -7.04 (16)°. In the crystal, mol­ecules are linked by N-H...S hydrogen-bond inter­actions, forming centrosymmetric dimers. Additionally, one weak intra­molecular N-H...N hydrogen-bond inter­action is observed. The crystal packing shows a herringbone arrangement viewed along the c axis.

Dual descriptions of massive spin-3 particles in D=2+1 via Noether gauge embedment

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Spectroscopic, Structural, and Conformational Properties of (Z)-4,4, 4-Trifluoro-3-(2-hydroxyethylamino)-1-(2-hydroxypheny1)-2-buten-1-one, C12H12F3NO3: A Trifluoromethyl-Substituted beta-Aminoenone

The ( Z)-4,4,4-trifluoro-3-(2-hydroxyethylamino)-1-(2-hydroxyphenyl)-2-buten-1-one (C12H12F3NO3) compound was thoroughly studied by IR, Raman, UV-visible, and C-13 and F-19 NMR spectroscopies. The solid-state molecular structure was determined by X-ray diffraction methods. It crystallizes in the P2(1)/c space group with a = 12.1420(4) angstrom, b = 7.8210(3) angstrom, c := 13.8970(5) angstrom, beta = 116.162(2)degrees, and Z = 4 molecules per unit cell. The molecule shows a nearly planar molecular skeleton, favored by intramolecular OH center dot center dot center dot 0 and NH center dot center dot center dot 0 bonds, which are arranged in the lattice as an OH center dot center dot center dot 0 bonded polymer coiled around crystallographic 2-fold screw-axes. The three postulated tautomers were evaluated using quantum chemical calculations. The lowest energy tautomer (I) calculated with density functional theory methods agrees with the observed crystal structure. The structural and conformational properties are discussed considering the effect of the intra- and intermolecular hydrogen bond interactions.

Magnetic moments of the low-lying J(P)=1/2(-), 3/2(-) Lambda resonances within the framework of the chiral quark model

The magnetic moments of the low-lying spin-parity J(P) = 1/2(-), 3/2(-) Lambda resonances, like, for example, Lambda(1405) 1/2(-), Lambda(1520) 3/2(-), as well as their transition magnetic moments, are calculated using the chiral quark model. The results found are compared with those obtained from the nonrelativistic quark model and those of unitary chiral theories, where some of these states are generated through the dynamics of two hadron coupled channels and their unitarization.

Messung des elektrischen Neutron-Formfaktors in der Reaktion 3 He(e,e'n)pp bei Q 2 = 1.58 (GeV/c) 2

Die elektromagnetischen Nukleon-Formfaktoren sind fundamentale Größen, welche eng mit der elektromagnetischen Struktur der Nukleonen zusammenhängen. Der Verlauf der elektrischen und magnetischen Sachs-Formfaktoren G_E und G_M gegen Q^2, das negative Quadrat des Viererimpulsübertrags im elektromagnetischen Streuprozess, steht über die Fouriertransformation in direkter Beziehung zu der räumlichen Ladungs- und Strom-Verteilung in den Nukleonen. Präzise Messungen der Formfaktoren über einen weiten Q^2-Bereich werden daher für ein quantitatives Verständnis der Nukleonstruktur benötigt.rnrnDa es keine freien Neutrontargets gibt, gestaltet sich die Messung der Neutron-Formfaktoren schwierig im Vergleich zu der Messung am Proton. Konsequenz daraus ist, dass die Genauigkeit der vorhandenen Daten von Neutron-Formfaktoren deutlich geringer ist als die von Formfaktoren des Protons; auch der vermessene Q^2-Bereich ist kleiner. Insbesondere der elektrische Sachs-Formfaktor des Neutrons G_E^n ist schwierig zu messen, da er aufgrund der verschwindenden Nettoladung des Neutrons im Verhältnis zu den übrigen Nukleon-Formfaktoren sehr klein ist. G_E^n charakterisiert die Ladungsverteilung des elektrisch neutralen Neutrons und ist damit besonders sensitiv auf die innere Struktur des Neutrons.rnrnIn der hier vorgestellten Arbeit wurde G_E^n aus Strahlhelizitätsasymmetrien in der quasielastischen Streuung vec{3He}(vec{e}, e'n)pp bei einem Impulsübertrag von Q^2 = 1.58 (GeV/c)^2 bestimmt. Die Messung fand in Mainz an der Elektronbeschleunigeranlage Mainzer Mikrotron innerhalb der A1-Kollaboration im Sommer 2008 statt. rnrnLongitudinal polarisierte Elektronen mit einer Energie von 1.508 GeV wurden an einem polarisierten ^3He-Gastarget, das als effektives, polarisiertes Neutrontarget diente, gestreut. Die gestreuten Elektronen wurden in Koinzidenz mit den herausgeschlagenen Neutronen detektiert; die Elektronen wurden in einem magnetischen Spektrometer nachgewiesen, durch den Nachweis der Neutronen in einer Matrix aus Plastikszintillatoren wurde der Beitrag der quasielastischen Streuung am Proton unterdrückt.rnrnAsymmetrien des Wirkungsquerschnitts bezüglich der Elektronhelizität sind bei Orientierung der Targetpolarisation in der Streuebene und senkrecht zum Impulsübertrag sensitiv auf G_E^n / G_M^n; mittels deren Messung kann G_E^n bestimmt werden, da der magnetische Formfaktor G_M^n mit vergleichsweise hoher Präzision bekannt ist. Zusätzliche Messungen der Asymmetrie bei einer Polarisationsorientierung parallel zum Impulsübertrag wurden genutzt, um systematische Fehler zu reduzieren.rnrnFür die Messung inklusive statistischem (stat) und systematischem (sys) Fehler ergab sich G_E^n = 0.0244 +/- 0.0057_stat +/- 0.0016_sys.