Propranolol reduces variceal pressure and wall tension in schistosomiasis presinusoidal portal hypertension

Background and Aim: Although prophylaxis with beta-blockers has been shown to decrease variceal pressure and wall tension in cirrhotic patients, this has not been demonstrated in non-cirrhotic portal hypertension caused by Schistosoma mansoni infection. Methods: Thirteen patients without history of previous gastrointestinal bleeding were included. All of them had high-risk esophageal varices at endoscopy. An endoscopic gauge and a high-frequency endoscopic ultrasonography miniprobe were used to assess transmural variceal pressure and wall tension before and after achieving beta-blockade with propranolol. Results: Baseline variceal pressure decreased from 13.3 +/- 3.5 to 8.2 +/- 2.0 mmHg (P < 0.0001) and wall tension from 500.2 +/- 279.8 to 274.0 +/- 108.3 mg.mm-1. The overall effect of propranolol on decreasing variceal pressure and wall tension expressed in percentage change in relation to baseline values was 35.7 +/- 18.4% and 35.9 +/- 26.7%, respectively (P = 0.9993). Conclusion: Propranolol significantly reduced variceal pressure and wall tension in schistosomiasis.

Combining Monte Carlo simulation and density-functional theory to describe the spectral changes of Na(2) in liquid helium

Spectral changes of Na(2) in liquid helium were studied using the sequential Monte Carlo-quantum mechanics method. Configurations composed by Na(2) surrounded by explicit helium atoms sampled from the Monte Carlo simulation were submitted to time-dependent density-functional theory calculations of the electronic absorption spectrum using different functionals. Attention is given to both line shift and line broadening. The Perdew, Burke, and Ernzerhof (PBE1PBE, also known as PBE0) functional, with the PBE1PBE/6-311++G(2d,2p) basis set, gives the spectral shift, compared to gas phase, of 500 cm(-1) for the allowed X (1)Sigma(+)(g) -> B (1)Pi(u) transition, in very good agreement with the experimental value (700 cm(-1)). For comparison, cluster calculations were also performed and the first X (1)Sigma(+)(g) -> A (1)Sigma(+)(u) transition was also considered.

Cross Section and Parity-Violating Spin Asymmetries of W(+/-) Boson Production in Polarized p plus p Collisions at root s=500 Gev

Large parity-violating longitudinal single-spin asymmetries A(L)(e+) = 0.86(-0.14)(+0.30) and Ae(L)(e-) = 0.88(-0.71)(+0.12) are observed for inclusive high transverse momentum electrons and positrons in polarized p + p collisions at a center-of-mass energy of root s = 500 GeV with the PHENIX detector at RHIC. These e(+/-) come mainly from the decay of W(+/-) and Z(0) bosons, and their asymmetries directly demonstrate parity violation in the couplings of the W(+/-) to the light quarks. The observed electron and positron yields were used to estimate W(+/-) boson production cross sections for the e(+/-) channels of sigma(pp -> W(+)X) X BR(W(+) -> e(+) nu(e)) = 144.1 +/- 21.2(stat)(-10.3)(+3.4)(syst) +/- 21.6(norm) pb, and sigma(pp -> W(-)X) X BR(W(-) -> e(-) (nu) over bar (e)) = 3.17 +/- 12.1(stat)(-8.2)(+10.1)(syst) +/- 4.8(norm) pb.

Energy systems contributions in 2,000 m race simulation: a comparison among rowing ergometers and water

This study investigated the energy system contributions of rowers in three different conditions: rowing on an ergometer without and with the slide and rowing in the water. For this purpose, eight rowers were submitted to 2,000 m race simulations in each of the situations defined above. The fractions of the aerobic (W(AER)), anaerobic alactic (W(PCR)) and anaerobic lactic (W([La-])) systems were calculated based on the oxygen uptake, the fast component of excess post-exercise oxygen uptake and changes in net blood lactate, respectively. In the water, the metabolic work was significantly higher [(851 (82) kJ] than during both ergometer [674 (60) kJ] and ergometer with slide [663 (65) kJ] (P <= 0.05). The time in the water [515 (11) s] was higher (P < 0.001) than in the ergometers with [398 (10) s] and without the slide [402 (15) s], resulting in no difference when relative energy expenditure was considered: in the water [99 (9) kJ min(-1)], ergometer without the slide [99.6 (9) kJ min(-1)] and ergometer with the slide [100.2 (9.6) kJ min(-1)]. The respective contributions of the WAER, WPCR and W[La-] systems were water = 87 (2), 7 (2) and 6 (2)%, ergometer = 84 (2), 7 (2) and 9 (2)%, and ergometer with the slide = 84 (2), 7 (2) and 9 (1)%. (V) over dotO(2), HR and lactate were not different among conditions. These results seem to indicate that the ergometer braking system simulates conditions of a bigger and faster boat and not a single scull. Probably, a 2,500 m test should be used to properly simulate in the water single-scull race.

Enzymatic and structural characterization of a basic phospholipase A(2) from the sea anemone Condylactis gigantea

This work aimed at the isolation and structural/functional characterization of a phospholipase A(2) (CgPLA(2)) from the extract of the anemone Condylactis gigantea. CgPLA2 was isolated with a high purity level through three chromatographic steps, showing pT8.6 and molecular weights of 14,500 and 29,000 for the monomer and dimer, respectively. CgPLA2 showed a high catalytic activity upon fluorescent phospholipids inducing no direct hemolytic activity. This enzyme, which is Ca2+-dependent, showed a lower stability against temperature and pH variations when compared with snake venom enzymes. The enzymatic activity was significantly reduced or completely abolished after chemical modification of CgPLA2 with BPB. Its cDNA was then obtained, with 357 base pairs which codified for a mature protein of 119 amino acid residues. A comparative analysis of the primary structure of CgPLA2 revealed 84%, 61%, 43% and 42% similarity to the PLA2s from Adamsia carciniopados, Nematostella vectensis, Vipera russelli russelli and Both raps jararacussu, respectively. (C) 2010 Elsevier Masson SAS. All rights reserved.

EVALUATION OF ONYX HD-500 EMBOLIC SYSTEM IN THE TREATMENT OF 84 WIDE-NECK INTRACRANIAL ANEURYSMS

OBJECTIVE: We report our results using Onyx HD-500 (Micro Therapeutics, Inc., Irvine, CA) in the endovascular treatment of wide-neck intracranial aneurysms, which have a high rate of incomplete occlusion and recanalization with platinum coils. METHODS: Sixty-nine patients with 84 aneurysms were treated. Most of the aneurysms were located in the anterior circulation (80 of 84 aneurysms), were unruptured (74 of 84 aneurysms), and were incidental. Ten presented with subarachnoid hemorrhage, and 15 were symptomatic. All aneurysms had wide necks (neck >4 mm and/or dome-to-neck ratio <1.5). Fifty aneurysms were small (<12 mm), 30 were large (12 to <25 mm) and 4 were giant. Angiographic follow-up was available for 65 of the 84 aneurysms at 6 months, for 31 of the 84 aneurysms at 18 months, and for 5 of the 84 aneurysms at 36 months. RESULTS: Complete aneurysm occlusion was seen in 65.5% of aneurysms on immediate control, in 84.6% at 6 months, and in 90.3% at 18 months. The rates of complete occlusion were 74%, 95.1%, and 95.2% for small aneurysms and 53.3%, 70%, and 80% for large aneurysms at the same follow-up periods. Progression from incomplete to complete occlusion was seen in 68.2% of all aneurysms, with a higher percentage in small aneurysms (90.9%). Aneurysm recanalization was observed in 3 patients (4.6%), with retreatment in 2 patients (3.3%). Procedural mortality was 2.9%. Overall morbidity was 7.2%. CONCLUSION: Onyx embolization of intracranial wide-neck aneurysms is safe and effective. Morbidity and mortality rates are similar to those of other current endovascular techniques. Larger samples and longer follow-up periods are necessary.

Progression of Diet-Induced Diabetes in C57BL6J Mice Involves Functional Dissociation of Ca(2+) Channels From Secretory Vesicles

OBJECTIVE The aim of the study was to elucidate the cellular mechanism underlying the suppression of glucose-induced insulin secretion in mice fed a high-fat diet (HFD) for 15 weeks. RESEARCH DESIGN AND METHODS-C57BL6J mice were fed a HFD or a normal diet (ND) for 3 or 15 weeks. Plasma insulin and glucose levels in vivo were assessed by intraperitoneal glucose tolerance test. Insulin secretion in vitro was studied using static incubations and a perfused pancreas preparation. Membrane currents, electrical activity, and exocytosis were examined by patch-clamp technique measurements. Intracellular calcium concentration ([Ca(2+)](i)) was measured by microfluorimetry. Total internal reflection fluorescence microscope (TIRFM) was used for optical imaging of exocytosis and submembrane depolarization-evoked [Ca(2+)](i). The functional data were complemented by analyses of histology and gene transcription. RESULTS After 15 weeks, but not 3 weeks, mice on HFD exhibited hyperglycemia and hypoinsulinemia. Pancreatic islet content and beta-cell area increased 2- and 1.5-fold, respectively. These changes correlated with a 20-50% reduction of glucose-induced insulin secretion (normalized to insulin content). The latter effect was not associated with impaired electrical activity or [Ca(2+)](i) signaling. Single-cell capacitance and TIRFM measurements of exocytosis revealed a selective suppression (>70%) of exocytosis elicited by short (50 ms) depolarization, whereas the responses to longer depolarizations were (500 ms) less affected. The loss of rapid exocytosis correlated with dispersion of Ca(2+) entry in HFD beta-cells. No changes in gene transcription of key exocytotic protein were observed. CONCLUSIONS HFD results in reduced insulin secretion by causing the functional dissociation of voltage-gated Ca(2+) entry from exocytosis. These observations suggest a novel explanation to the well-established link between obesity and diabetes. Diabetes 59:1192-1201, 2010

Effect of Eu(2)O(3) doping on Ta(2)O(5) crystal growth by the laser-heated pedestal technique

High energy band gap hosts doped with lanthanide ions are suitable for optical devices applications To study the potential of Ta(2)O(5) as a host compound pure and Eu(2)O(3)-doped Ta(2)O(5) crystal fibers were grown by the laser-heated pedestal growth technique in diameters ranging from 250 to 2600 pm and in lengths of up to 50 mm The axial temperature gradient at the solid/liquid interface of pure Ta(2)O(5) fibers revealed a critical diameter of 2200 gm above which the fiber cracks X-ray diffraction measurements of the pure Ta(2)O(5) single crystals showed a monoclinic symmetry and a growth direction of [1 (1) over bar 0] An analysis of the pulling rate as a function of the fiber diameter for Eu(2)O(3)-doped Ta(2)O(5) fibers indicated a well defined region in which constitutional supercooling is absent Photoluminescence measurements of pure Ta(2)O(5) crystals using excitation above the band gap (3 8 eV) were dominated by a broad unstructured green band that peaked at 500 nm Three Eu(3+)-related optical centers were identified in the doped samples with nominal concentrations exceeding 1 mol% Two of these centers were consistent with the ion in the monoclinic phase with different oxygen coordinations The third one was visible in the presence of the triclinic phase (C) 2010 Elsevier B V All rights reserved

Isotopic evidence for the late Brasiliano (500-550 Ma) ore-forming mineralization of the Araes gold deposit, Brazil

The Araes gold deposit, located in eastern Mato Grosso State, central Brazil, is hosted in Neoproterozoic volcanosedimentary rocks of the Paraguay belt, which formed during collision of the Amazonian craton and the Rio Apa block. Ar-40/Ar-39 geochronology and Pb and S isotopic analyses constrain the timing and sources of mineralization. Three biotite flakes from two samples of metavolcanic host rock yield Ar-40/Ar-39 plateau ages between 5941 and 531 Ma, interpreted as cooling ages following regional metamorphism. Clay minerals from a hydrothermal alteration zone yield an Ar-40/Ar-39 integrated age of 503 +/- 3 Ma. Galena grains from ore-bearing veins yield values of Pb-206/(204)pb from 17.952 to 18.383, Pb-207/Pb-204 from 15.156 to 15.811, and Pb-208/Pb-204 from 38.072 to 39.681. Pyrite grains from ore-bearing veins yield values of Pb-206/Pb-204 from 18.037 to 18.202, Pb-207/Pb-204 from 15.744 to 15.901., and Pb-208/(204)pb from 38.338 to 38.800. Pb isotope variations may be explained in terms of mixing a less radiogenic lead component (mu similar to 8.4) from mafic and ultramafic basement host-rocks (Nova Xavantina metavolcanosedimentary rocks) and a more radiogenic lead component (mu similar to 9.2) probably derived from supracrustal rocks (Cuiaba sedimentary groups). Sulfur isotope compositions are homogeneous, with delta S-34 values ranging from -1.1 parts per thousand to 0.9 parts per thousand (galena) and -0.7 parts per thousand to 0.9 parts per thousand (pyrite), suggesting a mantle-derived reservoir for the mineralizing solutions. Based on the Ar, Pb, and S isotope data, we suggest that the precious metals were remobilized from metavolcanic host rocks by hydrothermal solutions during Brasilide-Panafrican regional metamorphism. The Arabs gold deposit probably formed during a late stage of the orogeny, coeval with other mineralization events in the Paraguay Belt.

Radical acetylation of 2`-deoxyguanosine and L-histidine coupled to the reaction of diacetyl with peroxynitrite in aerated medium

Diacetyl, like other alpha-dicarbonyl compounds, is reportedly cytotoxic and genotoxic. A food and cigarette contaminant, it is related with alcohol hepatotoxicity and lung disease. Peroxynitrite is a potent oxidant formed in vivo by the diffusion-controlled reaction of the superoxide radical anion with nitric oxide, which is able to form adducts with carbon dioxide and carbonyl compounds. Here, we investigate the nucleophilic addition of peroxynitrite to diacetyl forming acetyl radicals, whose reaction with molecular oxygen leads to acetate. Peroxynitrite is shown to react with diacetyl in phosphate buffer (bell-shaped pH profile with maximum at 7.2) at a very high rate constant (k(2) = 1.0 X 10(4) M-1 s(-1)) when compared with monocarbonyl substrates (k(2) < 10(3) M-1 s(-1)). Phosphate ions (100-500 MM) do not affect the rate of spontaneous peroxynitrite decay, but the H2PO4- anion catalyzes the nucleophilic addition of the peroxynitrite anion to diacetyl. The intermediacy of acetyl radicals is suggested by a three-line spectrum (a(N) = a(H) = 0.83 mT) obtained by EPR spin trapping of the reaction mixture with 2-methyl-2-nitrosopropane. The peroxynitrite reaction is accompanied by concentration-dependent oxygen uptake. Stoichiometric amounts of acetate from millimolar amounts of peroxynitrite and diacetyl were obtained under nonlimiting conditions of dissolved oxygen. In the presence of either L-histidine or 2`-deoxyguanosine, the peroxynitrite/diacetyl system afforded the corresponding acetylated molecules identified by HPLC-MS"". These studies provide evidence that the peroxynitrite/diacetyl reaction yields acetyl radicals and raise the hypothesis that protein and DNA nonenzymatic acetylation may occur in cells and be implicated in aging and metabolic disorders in which oxygen and nitrogen reactive species are putatively involved.

Ultrasensitive Simultaneous Quantification of 1,N(2)-Etheno-2 `-deoxyguanosine and 1,N(2-)Propano-2 `-deoxyguanosine in DNA by an Online Liquid Chromatography-Electrospray Tandem Mass Spectrometry Assay

Exocyclic DNA adducts produced by exogenous and endogenous compounds are emerging as potential tools to study a variety of human diseases and air pollution exposure. A highly sensitive method involving online reverse-phase high performance liquid chromatography with electrospray tandem mass spectrometry detection in the multiple reaction monitoring mode and employing stable isotope-labeled internal standards was developed for the simultaneous quantification of 1,N(2)-etheno-2`-deoxyguanosine (1,N(2)-epsilon dGuo) and 1,N(2)-propano-2`-deoxyguanosine (1,N(2)-propanodGuo) in DNA. This methodology permits direct online quantification of 2`-deoxyguanosine and ca. 500 amol of adducts in 100 mu g of hydrolyzed DNA M the same analysis. Using the newly developed technique, accurate determinations of 1,N(2)-etheno-2`-deoxyguanosine and 1,N2-propano-2`-deoxyguanosine levels in DNA extracts of human cultured cells (4.01 +/- 0.32 1,N(2)-epsilon dGuo/10(8) dGuo and 3.43 +/- 0.33 1,N(2)-propanodGuo/10(8) dGuo) and rat tissue (liver, 2.47 +/- 0.61 1,N(2)-epsilon dGuo/10(8) dGuo and 4.61 +/- 0.69 1,N(2)-propanodGuo/108 dGuo; brain, 2.96 +/- 1.43,N(2)-epsilon dGuo/10(8) dGuo and 5.66 +/- 3.70 1,N(2)-propanoclGuo/10(8) dGuo; and lung, 0,87 +/- 0.34 1,N(2)-edGuo/ 10(8) dGuo and 2.25 +/- 1.72 1,N(2)-propanodGuo/10(8) dGuo) were performed. The method described herein can be used to study the biological significance of exocyclic DNA adducts through the quantification of different adducts in humans and experimental an with pathological conditions and after air pollution exposure.

Myoglobin-H(2)O(2) catalyzes the oxidation of beta-ketoacids to alpha-dicarbonyls: Mechanism and implications in ketosis

Acetoacetate (AA) and 2-methylacetoacetate (MAA) are accumulated in metabolic disorders such as diabetes and isoleucinemia. Here we examine the mechanism of AA and MAA aerobic oxidation initiated by myoglobin (Mb)/H(2)O(2). We propose a chemiluminescent route involving a dioxetanone intermediate whose thermolysis yields triplet alpha-dicarbonyl species (methylglyoxal and diacetyl). The observed ultraweak chemiluminescence increased linearly on raising the concentration of either Mb (10-500 mu M) or AA (10-100 mM). Oxygen uptake studies revealed that MAA is almost a 100-fold more reactive than AA. EPR spin-trapping studies with MNP/MAA revealed the intermediacy of an alpha-carbon-centered radical and acetyl radical. The latter radical, probably derived from triplet diacetyl, is totally suppressed by sorbate, a well-known quencher of triplet carbonyls. Furthermore, an EPR signal assignable to MNP-AA(center dot) adduct was observed and confirmed by isotope effects. Oxygen consumption and a-dicarbonyl yield were shown to be dependent on AA or MAA concentrations (1-50 mM) and on H(2)O(2) or tert-butOOH added to the Mb-containing reaction mixtures. That ferrylMb is involved in a peroxidase cycle acting on the substrates is suggested by the reaction pH profiles and immunospin-trapping experiments. The generation of radicals and triplet dicarbonyl products by Mb/H(2)O(2)/beta-ketoacids may contribute to the adverse health effects of ketogenic unbalance. (C) 2011 Elsevier Inc. All rights reserved.

Novel electroluminescent devices containing Eu(3+)-(2-acyl-1,3-indandionate) complexes with TPPO ligand

Fabrication and electroluminescent properties of devices containing europium complexes of general formula [Eu(ACIND)(3)(TPPO)(2)], where ACIND, 2-acyl-1,3-indandionate ligands: and TPPO, triphenylphosphine oxide. as emitter layers are discussed. The double-layer devices based on these complexes present the following configurations: device 1: ITO/TPD/[Eu(AlND)(3)(TPPO)(2)]/Al: device 2: ITO/TPD/[Eu(ISOV-IND)(3)(TPPO)(2)]/Al and device 3: ITO/TPD/[Eu(BIND)(3)(TPPO)(2)]/Al, where AlND, 2-acetyl-1,3-indandionate; ISOVIND, 2-isovaleryl-1,3-indandionate; and BIND, 2-benzoyl-1,3-indandionate, respectively. These devices exhibited photo and electroluminescent emissions. An important characteristic presented by devices is that their electroluminescent (EL) spectra, in the region of (5)D(0) -> (7)F(J) (J = 0, 1, 2, 3 and 4) transitions of Eu(3+) ion, show profiles that are different from photoluminescent (PL) ones. In addition to narrow bands arising from intraconfigurational-4f(6) transitions, devices 1 and 2 also exhibited a broad band with maximum at around 500 nm which is assigned to electrophosphorescence from the indandionate ligands. On the other hand, EL spectra of device 3 present only narrow bands from (5)D(0) -> (7)F(J) transitions. [Eu(ACIND)(3)(TPPO)(2)] complexes are promising candidates to prepare efficient organic light-emitting devices (OLEDs) when compared with those containing Eu(3+)-complexes of aliphatic beta-diketonate anions. (C) 2009 Elsevier B.V. All rights reserved.

Persistent luminescence of Eu(2+) and Dy(3+) doped barium aluminate (BaAl(2)O(4):Eu(2+),Dy(3+)) materials

Polycrystalline Eu(2+) and Dy(3+) doped barium aluminate materials, BaAl(2)O(4):Eu(2+),Dy(3+), were prepared with solid state reactions at temperatures between 700 and 1500 degrees C. The influence of the thermal treatments on the stability, homogeneity and structure as well as to the UV-excited and persistent luminescence of the materials was investigated by X-ray powder diffraction, SEM imaging and infrared spectroscopies as well as by steady state luminescence spectroscopy and persistent luminescence decay curves, respectively. The IR spectra of the materials prepared at 250, 700, and 1500 degrees C follow the formation of BaAl(2)O(4) composition whereas the X-ray powder diffraction of compounds revealed how the hexagonal structure was obtained. The morphology of the materials at high temperatures indicated important aggregation due to sintering. The luminescence decay of the quite narrow Eu(2+) band at ca. 500 nm shows the presence of persistent luminescence after UV irradiation. The dopant (Eu(2+)) and co-clopant (Dy(3+)) concentrations affect the crystallinity and luminescence properties of the materials. (C) 2009 Elsevier B.V. All rights reserved.