Dextrin-microencapsulated porphyrin - Luminescent properties

Photophysical properties of porphyrins in aqueous solutions are strongly affected by aggregation. One possible solution to this problem is to encapsulate the porphyrin into polymeric spheres, to provide an environment where the photosensitizer can be administered in its monomeric form in such treatments as photodynamic therapy. Here we report the microencapsulation of the meso-tetrakis(4-sulphonatophenyl) porphyrin (TPPS4) photosensitizer by the ultrasonic spray-drying technique. The encapsulated TPPS4 was morphologically characterized by scanning electron microscopy, and its photophysical properties were studied and compared with those of a physical blend of dextrin and TPPS4. We Successfully encapsulated TPPS4 into dextrin microspheres, and the encapsulated photosensitizer displays higher luminescence intensity than that of the prepared physical blends.

Biochemical properties of an extracellular beta-D-fructofuranosidase II produced by Aspergillus phoenicis under Solid-Sate Fermentation using soy bran as substrate

The filamentous fungus A. phoenicis produced high levels of beta-D-fructofuranosidase (FFase) when grown for 72 hrs under Solid-State Fermentation (SSF), using soy bran moistened with tap water (1:0.5 w/v) as substrate/carbon source. Two isoforms (I and II) were obtained, and FFase II was purified 18-fold to apparent homogeneity with 14% recovery. The native molecular mass of the glycoprotein (12% of carbohydrate content) was 158.5 kDa with two subunits of 85 kDa estimated by SDS-PAGE. Optima of temperature and pH were 55 degrees C and 4.5. The enzyme was stable for more than 1 hr at 50 degrees C and was also stable in a pH range from 7.0 to 8.0. FFase II retained 80% of activity after storage at 4 degrees C by 200 hrs. Dichroism analysis showed the presence of random and beta-sheet structure. A. phoenicis FFase II was activated by Mn(2+), Mg(2+) and Co(2+), and inhibited by Cu(2+), Hg(2+) and EDTA. The enzyme hydrolyzed sucrose, inulin and raffinose. K(d) and V(max) values were 18 mM and 189 U/mg protein using sucrose as substrate.

Rare Earth Doped SnO(2) Nanoscaled Powders and Coatings: Enhanced Photoluminescence in Water and Waveguiding Properties

Luminescent Eu(3+) and Er(3+) doped SnO(2) powders have been prepared by Sn(4+) hydrolysis followed by a controlled growth reaction using a particle`s surface modifier in order to avoid particles aggregation. The powders so obtained doped with up to 2 mol% rare earth ions are fully redispersable in water at pH > 8 and present the cassiterite structure. Particles size range from 3 to 10 nm as determined by Photon Correlation Spectroscopy. Rare earth ions were found to be essentially incorporated into the cassiterite structure, substituting for Sn(4+), for doping concentration smaller than 0.05 mol%. For higher concentration they are also located at the particles surface. The presence of Eu(3+) ions at the surface of the particles hinder their growth and has therefore allowed the preparation of new materials consisting of water redispersable powders coated with Eu(3+)-beta dike-tonate complexes. Enhanced UV excited photoluminescence was observed in water. SnO(2) single layers with thickness up to 200 nm and multilayer coatings were spin coated on borosilicate glass substrates from the colloidal suspensions. Waveguiding properties were evaluated by the prism coupling technique. For a 0.3 mu m planar waveguide single propagating mode was observed with attenuation coefficient of 3.5 dB/cm at 632.8 nm.

Syntheses, electrochemistry and photophysical properties of a series of meso-pyridylpentafluorophenylporphyrins

This work presents the synthesis and characterization of a series of substituted pyridylpentafluroporphyrins, including the separation of the cis- and trans-isomers, the latter being characterized by X-ray crystallography. The spectroscopic and electrochemical properties of the series are dependent on the number of electron withdrawing pentafluorophenyl substituent, but they do not depend on the symmetry of the molecule. Ongoing from the monosubstituted to the more substituted pentafluorophenyl porphyrin H(2)(MPyTFPP) derivative, the Soret bands are slightly red-shifted and their quantum fluorescence yields range from 0.035 to 0.046, consistent with the value of 0.045 for the fully substituted 5,10,15,20-tetrapentafluorophenylporphyrin (dichloromethane solutions). The redox potentials of the reductive processes of monoanion and dianion formation are also sensitive to the number of pentafluoro substituents, shifting 180 mV to more positive values for the P(0)/P(-1) process ongoing from the monopentafluoro to the tris-pentafluorophenyl substituted derivative.

A new oxovanadium(IV)-cucurbit[6]uril complex: Properties and potential for confined heterogeneous catalytic oxidation reactions

This work presents a new oxovanadium(IV)-cucurbit[6]uril complex, which combines the catalytic properties of the metal ion with the size-excluding properties of the macrocycle cavity. In this coordination compound, the VO(2-) ions are coordinated to the oxygen atoms located at the rim of the macrocycle in slightly distorted square-pyramidal configurations, which are in fact C(2v) symmetries. This combination results in a size-selective heterogeneous catalyst, which is able to oxidize linear alkanes like n-pentane at room temperature, but not styrene, cyclohexane or z-cyclooctene, which are too big to enter the cucurbit[6]uril cavity. The results presented here contribute to understanding the mechanism of alkane catalytic oxidation by oxovanadium(IV) complexes. (C) 2010 Elsevier Ltd. All rights reserved.

Synthesis, characterization, and catalytic properties of a mesostructured lamellar xerogel tungsten oxide phase

Cetyltrimethylammonium bromide (CTAB) and n-hexadecylamine (HDA) have been used as template in the synthesis of a mesolamellar xerogel tungsten oxide phase (WO(3)/CTAB/HDA). The catalytic properties of the resulting material were investigated in the oxidation of cis-cyclooctene, styrene, and cyclohexane, using hydrogen peroxide (H(2)O(2)), terc-butyl hydroperoxide (t-BOOH), or m-chlorperbenzoic acid (m-CPBA) as oxygen transfer agent. In general, the catalytic results were comparable to those obtained with related systems, thus suggesting the potential application of this material as catalyst for epoxidation reactions. (C) 2011 Elsevier B.V. All rights reserved.

Study of spectroscopic properties of Europium (III) Tris(beta-diketonate) complex and alpha-Cyclodextrin in aqueous medium

The solubilization of an europium (III) beta-diketonate chelate in aqueous medium and the changes in its photophysical properties upon its inclusion into an alpha-cyclodextrin hydrophobic cavity are described. The complex [Eu(tta)(3)center dot(H(2)O)(2)] (tta = 4,4,4-trifluoro-1-(thiophen-2-yl)butane-1,3-dione) was synthesized, characterized, and incorporated into the hydrophobic cavity by stirring in an alpha-cyclodextrin aqueous solution. The inclusion was confirmed by (1)H NMR, and the stoichiometry of association was obtained by the Job method. The maximum in the excitation spectrum of the alpha-CD inclusion compound in aqueous solution was shifted 28 nm compared with the maximum of non alpha-CD complex. The emission spectrum of the association is similar to that of the free solid complex and displays the characteristic (5)D(0) -> (7)F(0-4) Eu(3+) transitions.

Spectroelectrochemical Properties and Lithium Ion Storage in Self-Assembled Nanocomposites from TiO(2)

Layer-by-layer (LbL) nanocomposite films from TiO(2) nanoparticles and tungsten-based oxides (WO(x)H(y)), as well as dip-coating films of TiO(2) nano particles, were prepared and investigated by electrochemical techniques under visible light beams, aiming to evaluate the lithium ion storage and chromogenic properties. Atomic force microscopy (AFM) images were obtained for morphological characterization of the Surface of the materials, which have similar roughness. Cyclic voltammetry and chronoamperometry measurements indicated high storage capacity of lithium ions in the LbL nanocomposite compared with the dip-coating film, which was attributed to the faster lithium ion diffusion rate within the self-assembled matrix. On the basis of the data obtained from galvanostatic intermittent titration technique (GITT), the values of lithium ion diffusion coefficient (D(Li)) for TiO(2)/WO(x)H(y) were larger compared with those for TiO(2). The rate of the coloration front in the matrices was investigated using a spectroelectrochemical method based oil GITT, allowing the determination of the ""optical"" diffusion coefficient (D(op)) as a function of the amount of lithium ions previously inserted into the matrices. The Values of D(Li) and D(op) suggested the existence of phases with distinct contribution to lithium ion diffusion rates and electrochromic efficiency. Moreover, these results aided a better understanding of the temporal change of current density and absorbance during the ionic electro-insertion, which is important for the possible application of these materials in lithium ion batteries and electrohromic devices.

Synthesis and electrochemical properties of vanadyl phosphate di-hydrate/polyaniline derivatives hybrid films

Vanadyl phosphate and its hybrid compounds have proven to undergo electrochemical intercalation and de-intercalation of lithium ions, which enables its use as cathode material for Li ion rechargeable batteries. In this context, vanadyl phosphate di-hydrate/polyaniline derivatives hybrid films were synthesized via the exfoliation and reconstruction approach in order to evaluate their potential use as cathode in ion lithium batteries. X-ray diffraction patterns indicate that the lamellar structure of the inorganic matrix is maintained, consistent with the topotactic process. In the scanning electron micrographs, hybrid films exhibit rough surface consisting of warped and cracked crystallites, quite different from vanadyl phosphate di-hydrate square platelets crystallites. Electrochemical evaluation using cyclic voltammetry and charge-discharge galvanostatic techniques shows small differences between the charge and the discharge curves, indicating an irreversibility of the hybrid systems. (C) 2009 Elsevier B.V. All rights reserved.

Biomechanical failure properties and microstructural content of ruptured and unruptured abdominal aortic aneurysms

Purpose: To test the hypothesis that ruptured abdominal aortic aneurysms (AAA) are globally weaker than unruptured ones. Methods: Four ruptured and seven unruptured AAA specimens were harvested whole from fresh cadavers during autopsies performed over an 18-month period. Multiple regionally distributed longitudinally oriented rectangular strips were cut from each AAA specimen for a total of 77 specimen strips. Strips were subjected to uniaxial extension until failure. Sections from approximately the strongest and weakest specimen strips were studied histologically and histochemically. From the load-extension data, failure tension, failure stress and failure strain were calculated. Rupture site characteristics such as location, arc length of rupture and orientation of rupture were also documented. Results: The failure tension, a measure of the tissue mechanical caliber was remarkably similar between ruptured and unruptured AAA (group mean +/- standard deviation of within-subject means: 11.2 +/- 2.3 versus 11.6 +/- 3.6 N/cin; p=0.866 by mixed model ANOVA). In post-hoc analysis, there was little difference between the groups in other measures of tissue mechanical caliber as well such as failure stress (95 +/- 28 versus 98 +/- 23 N/cm(2); p=0.870), failure strain (0.39 +/- 0.09 versus 0.36 +/- 0.09; p=0.705), wall thickness (1.7 +/- 0.4 versus 1.5 +/- 0.4 mm; p=0.470), and % coverage of collagen within tissue cross section (49.6 +/- 12.9% versus 60.8 +/- 9.6%; p=0.133). In the four ruptured AAA, primary rupture sites were on the lateral quadrants (two on left; one on left-posterior; one on right). Remarkably, all rupture lines had a longitudinal orientation and ranged from 1 to 6 cm in length. Conclusion: The findings are not consistent with the hypothesis that ruptured aortic aneurysms are globally weaker than unruptured ones. (C) 2011 Elsevier Ltd. All rights reserved.

Validation of the University of Sao Paolo Sensory Phenomena Scale: Initial Psychometric Properties

Introduction: Although obsessions and compulsions comprise the main features of obsessive-compulsive disorder (OCD), many patients report that their compulsions are preceded by a sense of ""incompleteness"" or other unpleasant feelings such as premonitory urges or a need perform action`s until feeling ""just right."" These manifestations have been characterized as Sensory Phenomena (SP). The current study presents initial psychometric data for a new scale designed to measure SP. Methods: Seventy-six adult OCD subjects were probed twice. Patients were assessed with an open clinical interview (considered as the ""gold standard"") and with the following standardized instruments: Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I Disorders, Yale-Brown Obsessive-Compulsive Scale, Dimensional Yale-Brown Obsessive-Compulsive Scale, Yale Global Tic Severity Scale, Beck Anxiety Inventory, and Beck Depression Inventory. Results: SP were present in 51 OCD patients (67.1%). Tics were present in 16 (21.1%) of the overall sample. The presence of SP was significantly higher in early-onset OCD patients. There were no significant differences in the presence of SP according to comorbidity with tics or gender. The comparison between the results from the open clinical interviews and the University of Sao Paulo Sensory Phenomena Scale (USP-SPS) showed an excellent concordance between them, with no significant differences between interviewers. The inter-rater reliability between the expert raters for the USP-SPS was high, with K=.92. The Pearson correlation coefficient between the SP severity scores given by the two raters was .89. Conclusion: Preliminary results suggest that the USP-SPS is a valid and reliable instrument for assessing the presence and severity of SP in OCD subjects. CNS Spectr. 2009;14(6):315-323

Effect of Exercise Training on Plasma Levels and Functional Properties of High-Density Lipoprotein Cholesterol in the Metabolic Syndrome

Intense lifestyle modifications can change the high-density lipoprotein (HDL) cholesterol concentration. The aim of the present study was to analyze the early effects of short-term exercise training, without any specific diet, on the HDL cholesterol plasma levels and HDL functional characteristics in patients with the metabolic syndrome (MS). We studied 30 sedentary subjects, 20 with and 10 without the MS. The patients with the MS underwent moderate intensity exercise training for 3 months on bicycle ergometers. Blood was sampled before and after training for biochemical analysis, paraoxonase-1 activity, and HDL subfraction composition and antioxidative capacity. Lipid transfer to HDL was assayed in vitro using a labeled nanoemulsion as the lipid donor. At baseline, the MS group had greater triglyceride levels and a lower HDL cholesterol concentration and lower paraoxonase-1 activity than did the controls. Training decreased the plasma triglycerides but did not change the low-density lipoprotein or HDL cholesterol levels. Nonetheless, exercise training increased the HDL subfractions` antioxidative capacity and paraoxonase-1 activity. After training, the MS group had compositional changes in the smallest HDL subfractions associated with increased free cholesterol and cholesterol ester transfers to HDL, reaching normal values. In conclusion, the present investigation has added relevant information about the dissociation between the quantitative and qualitative aspects of HDL after short-term exercise training without any specific diet in those with the MS, highlighting the importance of evaluating the functional aspects of the lipoproteins, in addition to their plasma levels. (C) 2011 Elsevier Inc. All rights reserved. (Am J Cardiol 2011;107:1168-1172)

Phenolics and Antioxidant Properties of Fruit Pulp and Cell Wall Fractions of Postharvest Banana (Musa acuminata Juss.) Cultivars

Banana fruits are important foods, but there have been very few studies evaluating the phenolics associated with their cell walls. In the present study, (+) catechin, gallocatechin, and (-) epicatechin, as well as condensed tannins, were detected in the soluble extract of the fruit pulp; neither soluble anthocyanidins nor anthocyanins were present. In the soluble cell wall fraction, two hydroxycinnamic acid derivatives were predominant, whereas in the insoluble cell wall fraction, the anthocyanidin delphinidin, which is reported in banana cell walls for the first time, was predominant. Cell wall fractions showed remarkable antioxidant capacity, especially after acid and enzymatic hydrolysis, which was correlated with the total phenolic content released after the hydrolysis of the water-insoluble polymer, but not for the posthydrolysis water-soluble polymer. The acid hydrolysis released various monosaccharides, whereas enzymatic hydrolysis released one peak of oligosaccharides. These results indicate that banana cell walls could be a suitable source of natural antioxidants and that they could be bioaccessible in the human gut.

A novel human CD4(+) T-cell inducer subset with potent immunostimulatory properties

The complexity of immunoregulation has focused attention on the CD4(+) T ""suppressor"" regulatory cell (T(reg)), which helps maintain balance between immunity and tolerance. An immunoregulatory T-cell population that upon activation amplifies cellular immune responses was described in murine models more than 30 years ago; however, no study has yet identified a naturally occurring T ""inducer"" cell type. Here, we report that the ectoenzyme CD39/NTPDase1 (ecto-nucleoside triphosphate diphosphohydrolase 1) helps to delineate a novel population of human ""inducer"" CD4(+) T cells (T(ind)) that significantly increases the proliferation and cytokine production of responder T cells in a dose-dependent manner. Furthermore, this unique T(ind) subset produces a distinct repertoire of cytokines in comparison to the other CD4(+) T-cell subsets. We propose that this novel CD4(+) T-cell population counterbalances the suppressive activity of suppressor T(reg) in peripheral blood and serves as a calibrator of immunoregulation.

Ranolazine Exerts Potent Effects on Atrial Electrical Properties and Abbreviates Atrial Fibrillation Duration in the Intact Porcine Heart

Introduction: In vitro studies and ambulatory ECG recordings from the MERLIN TIMI-36 clinical trial suggest that the novel antianginal agent ranolazine may have the potential to suppress atrial arrhythmias. However, there are no reports of effects of ranolazine on atrial electrophysiologic properties in large intact animals. Methods and Results: In 12 closed-chest anesthetized pigs, effects of intravenous ranolazine (similar to 9 mu M plasma concentration) on multisite atrial effective refractory period (ERP), conduction time (CT), and duration and inducibility of atrial fibrillation (AF) initiated by intrapericardial acetylcholine were investigated. Ranolazine increased ERP by a median of 45 ms (interquartile range 29-50 ms; P < 0.05, n = 6) in right and left atria compared to control at pacing cycle length (PCL) of 400 ms. However, ERP increased by only 28 (24-34) ms in right ventricle (P < 0.01, n = 6). Ranolazine increased atrial CT from 89 (71-109) ms to 98 (86-121) ms (P = 0.04, n = 6) at PCL of 400 ms. Ranolazine decreased AF duration from 894 (811-1220) seconds to 621 (549-761) seconds (P = 0.03, n = 6). AF was reinducible in 1 of 6 animals after termination with ranolazine compared with all 6 animals during control period (P = 0.07). Dominant frequency (DF) of AF was reduced by ranolazine in left atrium from 11.7 (10.7-20.5) Hz to 7.6 (2.9-8.8) Hz (P = 0.02, n = 6). Conclusions: Ranolazine, at therapeutic doses, increased atrial ERP to greater extent than ventricular ERP and prolonged atrial CT in a frequency-dependent manner in the porcine heart. AF duration and DF were also reduced by ranolazine. Potential role of ranolazine in AF management merits further investigation. (J Cardiovasc Electrophysiol, Vol. 20, pp. 796-802, July 2009).