958 resultados para Sigismund, emperor of Germany, d. 1437.


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This is a review of John Caputo’s recent Routledge book on religion. Caputo’s central idea is captured by the phrase ‘religion without religion’, by which he means a religious stance or attitude that is not circumscribed by allegiance to any specific creed.

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Extracellular adenosine 5′-triphosphate (ATP) is an agonist for the P2Z receptor of human leukaemic lymphocytes and opens a Ca 2+-selective ion channel, which also conducts Ba2+, Sr2+ and the small fluorescent dye, ethidium+. A wide range of receptor agonists, many of which raise cytosolic [Ca2+] activate phospholipase D (PLD). In the present study, it was shown that both ATP and 3′-O-(4-benzoylbenzoyl)-ATP (BzATP) stimulated PLD activity in a concentration-dependent manner, and the inhibitory effects of suramin, oxidised ATP, extracellular Na+ and Mg2+ suggested that the effect of these agonists is mediated by P2Z receptors. The role of divalent cations in ATP-stimulated PLD activity was investigated. Several agonists (eg ATP, thapsigargin, ionomycin) stimulated a rise in cytosolic [Ca2+] in human lymphocytes, but only ATP and ionomycin stimulated PLD activity. When Ca2+ influx was prevented by EGTA, the majority of ATP-stimulated and all of ionomycin-stimulated PLD activity was inhibited. Preloading cells with the Ca2+ chelator, BAPTA, reduced cytosolic [Ca2+] and, paradoxically, ATP-stimulated PLD activity was potentiated. ATP-stimulated PLD activity was supported by both Ba2+ and Sr2+ when they were substituted for extracellular Ca2+. Furthermore, both ATP-stimulated PLD activity and ATP-stimulated 133Ba2+ influx showed a linear dependence on extracellular [Ba2+]. Thus it was concluded that ATP stimulated PLD activity in direct proportion to the influx of divalent cations through the P2Z ion channel and this PLD activity was insensitive to changes in bulk cytosolic [Ca2+]. The calmodulin (Ca2+/CaM) inhibitor, trifluoperazine (TFP) inhibited ionomycin- and ATP-stimulated PLD activity and ATP-stimulated apoptosis, but had no effect on PLD activity already activated by ATP. However, TFP inhibited ATP-stimulated Ca2+, Ba2+ and ethidium+ fluxes, at concentrations below those which inhibit Ca2+/CaM, suggesting that TFP inhibits the P2Z receptor. Similarly, the isoquinolinesulphonamide, KN-62, a selective inhibitor of Ca2+/CaM-dependent protein kinase II (CaMKII), also prevented ATP-stimulated apoptosis, but had no effect on pre-activated PLD. In addition, KN-62, and an analogue, KN-04, which has no effect on CaMKII, potently inhibited ATP-stimulated Ba2+ influx (IC50 12.7 ± 1.5 and 17.3 ± 2.7 nM, respectively), ATP-stimulated ethidium+ uptake (IC50 13.1 ± 2.6 and 37.2 ± 8.9 nM, respectively), ATP-stimulated phospholipase D activity (50% inhibition 5.9 ± 1.2 and 9.7 ± 2.8 nM, respectively) and ATP-induced shedding of the surface adhesion molecule, L-selectin (IC50 31.5 ± 4.5 and 78.7 ± 10.8 nM, respectively). They did not inhibit phorbol ester- or ionomycin-stimulated PLD activity or phorbol ester-induced L-selectin shedding. Neither KN-62 nor KN-04 (both 500 nM) have any effect on UTP-stimulated Ca2+ transients in fura-2-loaded human neutrophils, a response which is mediated by the P2Y2 receptor, neither did they inhibit ATP-stimulated contractile responses mediated by the P2X1 receptor of guinea pig urinary bladder. Thus, KN-62 and KN-04 are almost equipotent as P2Z inhibitors with IC50s in the nanomolar, indicating that their actions cannot be due to CaMKII inhibition, but rather that they are potent and direct inhibitors of the P2Z receptor. Extracellular ATP-induced shedding of L-selectin from lymphocytes into the medium is a Ca2+-independent response. L-selectin is either cleaved by a metalloproteinase or a PLD with specificity for glycosylphosphatidylinositol (GPI). The novel hydroxamic acid-based zinc chelator, Ro-31-9790 blocks ATP-induced L-selectin shedding, but was without effect on ATP-induced Ba2+ influx or ATP-stimulated PLD activity. Furthermore, another zinc chelator, 1,10-phenanthroline, an inhibitor of a GPI-PLD, potentiated rather than inhibited ATP-stimulated PLD activity, suggesting that ATP-induced L-selectin shedding and ATP-stimulated PLD activity are independent of each other. Although extracellular ATP is the natural ligand for the lymphocyte P2Z receptor, it is less potent than BzATP in stimulating Ba2+ influx. Concentration-response curves for BzATP- and ATP-stimulated ethidium+ influx gave EC50s 15.4 ± 1.4 µM and 85.6 ± 8.8 µM, respectively. The maximal response to ATP was only 69.8 ± 1.9% of that for BzATP. Hill coefficients were 3.17 ± 0.24 and 2.09 ± 0.45 for BzATP and ATP respectively, suggesting greater positive cooperativity for BzATP than for ATP in opening the P2Z-operated ion channel. A rank order of agonist potency of BzATP > ATP = 2MeSATP > ATPγS was observed for agonist-stimulated ethidium+ influx, while maximal influxes followed a rank order of BzATP > ATP > 2MeSATP > ATPγS. When ATP (300 -1000 µM) was added simultaneously with 30 µM BzATP (EC90), it reduced both ethidium+ and Ba2+ fluxes by 30 - 40% relative to values observed with BzATP alone. KN-62, previously shown to be a specific inhibitor of the lymphocyte P2Z receptor, was a less potent antagonist of BzATP-induced fluxes than ATP, when maximal concentrations of both agonists (50 and 500 µM respectively) were used. However, when BzATP (18 µM) was used at a concentration equiactive with a maximally effective ATP concentration, KN-62 showed the same inhibitory potency for both agonists. The ecto-ATPase antagonist, ARL-67156, inhibited both ATP- and BzATP-stimulated Ba2+ influx, suggesting that the lower efficacy of ATP compared with BzATP was not due to preferential hydrolysis of ATP. Thus, the natural ligand, ATP, is a partial agonist for the P2Z receptor while BzATP is a full agonist. Moreover the competitive studies show that only a single class of P2-receptor (P2Z class) is expressed on human leukaemic lymphocytes. Both ATP- and BzATP-stimulated PLD activity were significantly inhibited (P < 0.05) when cells were suspended in iso-osmotic choline Cl medium. Choline+ was found to be a permeant for the P2Z ion channel, since ATP induced a large uptake of [14C]choline+ (60 to 150 µmol/ml intracellular water) during a 5 min incubation, which remained in the cells for several hours, and ATP was used to load cells with these levels of choline+. Intracellular choline+ inhibited ATP-, BzATP-, PMA- and ionomycin-stimulated PLD activity. Brief exposure of lymphocytes to ATP increased the subsequent basal rate of ethidium+ uptake, and this was prevented by intracellular choline+. It is proposed that P2Z-mediated Ca2+ influx in lymphocytes activates PLD leading to significantly changes of the phospholipid composition of the plasma membrane, which subsequently produces a permeability lesion, which in turn contributes to cell death.

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The rapid globalization of markets has resulted in further acceleration of the worldwide convergence of accounting standards, including the development of high-quality and globally consistent accounting standards for both domestic and cross-border financial reporting. Prior studies report that earnings value relevance of U.S. companies is decreasing, and the decline is partially attributable to the immediate expensing of intangibles, like research and development (R&D). Being one of the areas of divergence, accounting for R&D was highlighted as one of the seven short-term convergence projects by the FASB and IASB. Australia's adoption of IFRS in 2005 presents an empirical setting to evaluate the value relevance of different accounting treatments for R&D, and ultimately assist financial accounting standard setters in the U.S. and abroad in finding an appropriate accounting treatment for R&D.

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The paper reports key findings from a four year study of cross-sector collaborative R&D projects in Australia testing a theoretical model formulated to explain partner collaboration experience and perceived project success. The study contributes to the understanding of knowledge-intensive collaborations, and indicates how their benefits can be sustained under conditions of high uncertainty. The study was of cross-sector collaborative projects within the Australian Cooperative Research Centre (CRC) Program which involved multiple partners and which were focused on the commercialization of R&D. The model was empirically tested through a survey of project leaders and the results provided support for the three main effects hypothesized. The theoretical, methodological and practical implications of the study's findings for the field of interorganizational relations (IOR) are discussed, and a new construct of project management competence is proposed as a determinant of positive partner experiences at the project level. This study adds to the growing body of work on interorganizational collaborative arrangements by providing systematic empirical support for a theoretical model of cross-sector R&D collaboration at the project level and at the completion or near completion phase of project development.

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The miscibility of poly(d,l-lactide-co-glycolide) (PLG) with three amphiphilic molecules and the interaction of the PLG/surfactant mixtures with DNA at air/water interface are investigated by π-A isotherms, Brewster angle microscopy (BAM) and atomic force microscopy (AFM) techniques. The π-A isotherms of the PLG mixtures with cationic C12AzoC6PyBr, and C12AzoC6N(CH3)3Br, are quite different from the π-A isotherm of pure PLG on water subphase. In contrast to the case, the π-A isotherm of PLG mixed with nonionic C12AzoC6OPy is almost identical to the pure PLG except some increasing of molecular area. Similar phenomena are observed on DNA subphase. The in situ BAM and ex situ AFM observations demonstrate that the dispersion of PLG at air/water interface becomes good when it mixes with the two cationic surfactants, whereas quite poor due to the phase separation when it mixes with the nonionic amphiphilic molecule. Based on these results we conclude that the cationic surfactants can affect the conformation change of PLG at air/water interface and figure a well miscibility with polymer whereas the nonionic amphiphilic molecule presents poor miscibility. In addition, the even mixing of the PLG and the cationic surfactants is favorable for the adsorption to DNA more effectively.

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Reaction of CeCl3&middot;7H2O with Na2(oda) (oda = O(CH2CO2)22&mdash; oxydiacetate) in a 2:3 ratio gives the neutral cerium(III) complex [Ce2(oda)3(H2O)3]&middot;9H2O (1). Treatment of a 1:3 mixture of CeCl3&middot;7H2O and H2oda in water with 4 molar equivalents of NaOH also gives 1 but, with a larger excess of NaOH, the tri-sodium salt Na3[Ce(oda)3]&middot;9H2O (2) is isolated. Formation of a tri-ammonium analogue of 2 can be achieved by neutralisation of an aqueous solution of CeCl3&middot;7H2O and H2(oda) in a 1:3 ratio by NH4OH, giving (NH4)3[Ce(oda)3]&middot;7H2O (3). Use of the cerium(IV) reagent (NH4)2[Ce(NO3)6] with Na2(oda) results in reduction to cerium(III) under ambient conditions and isolation of 1. However, in the absence of light this reaction yields crystals of the novel cerium(IV) heterobimetallic [Ce(oda)3Na4(NO3)2] (4). Each of these complexes exhibit a 3-D network structure having a common nine-coordinate [Ce(oda)3]n&mdash; (n = 2 or 3) subunit, irrespective of the oxidation state of cerium. In 1, six [Ce(oda)3]3&mdash; anions are connected, through bridging bidentate carboxylates, to a second Ce3+ site further coordinated by three water molecules. In contrast, the ammonium salt 2, displays isolated [Ce(oda)3]3&mdash; anions, devoid of further carboxylate bonding, but enmeshed within a network of hydrogen-bonded NH4+ cations and water molecules. The remarkable structure of 4 consists of infinite 2-D sheets of [Na2(NO3)]+ pillared by [Ce(oda)3]2&mdash; units, the connectivity arising by multidentate nitrate and carboxylate bridging.

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Migration to industrialised countries poses a &ldquo;double whammy&rdquo; for type 2 diabetes among sub-Saharan African migrant and refugee adults. This population group has been found to be at an increased risk of obesity and type 2 diabetes, which may be further aggravated by inadequate vitamin D status. Thus, this study aimed to describe the demographics of vitamin D insufficiency, obesity, and risk factors for type 2 diabetes among sub-Saharan African migrants and refugees aged 20 years or older living in Melbourne, Australia (n=49). Data were obtained by a questionnaire, medical assessment, and fasting blood samples. The mean serum 25-hydroxyvitamin D level was 27.3 nmol/L (95% CI: 22.2, 32.4 nmol/L); with 25-hydroxyvitamin D levels <50 nmol/L occurring in 88% of participants. Participants displayed a cluster of risk factors for type 2 diabetes and cardiovascular disease: 62% were overweight or obese, 47% had insulin resistance (HOMA-IR ≥2), 25% had low density lipoprotein cholesterol levels ≥3.5 mmol/L, 24.5% had high density lipoprotein cholesterol levels ≤1.03 mmol/L, 34.6% had borderline or high levels of total cholesterol (≥5.2 mmol/L), 18.2% had borderline or high levels of triglyceride (≥1.7 mmol/L), and 16% had hypertension (systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg). These findings suggest that sub-Saharan African migrants and refugees may be at risk of type 2 diabetes and atherosclerosis-related diseases such as ischemic heart disease, stroke, and peripheral vascular disease. Well-designed vitamin D interventions that incorporate lifestyle changes are urgently needed in this sub-population.

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Background</b>: Vitamin D deficiency is common. Recently Roche Diagnostics removed their Elecsys Vitamin D3 (25OH) electrochemiluminescence immunoassay (ECLIA) from use, citing deteriorating traceability to the reference method (liquid chromatography tandem mass spectrometry; LCMSMS). We investigated the performance of the Roche assay (2 assay formulations) against an LCMSMS method and the widely used DiaSorin radioimmunoassay (RIA) method.

Methods: Two sets of samples from separate populations were assayed for vitamin D. The first set was assayed using three different methods: RIA (DiaSorin) in 2004, polyclonal ECLIA (Roche) in early 2009 and LCMSMS in early 2010. The second set was assayed using polyclonal and monoclonal ECLIA (Roche) and LCMSMS in mid-2010.

Results: The correlation of the polyclonal ECLIA with the RIA was poor (ECLIA = 0.45 x RIA + 19, r2 = 0.59, n = 773). LCMSMS results correlated with RIA (RIA = 0.86 x LCMSMS + 4, r2 = 0.69, n = 49) better than with polyclonal ECLIA (polyclonal ECLIA = 0.55 x LCMSMS + 6, r2 = 0.62, n = 55) despite a storage interval of 6 years.

In recently collected samples monoclonal and polyclonal immunoassays gave similar results (monoclonal ECLIA = 0.93 polyclonal ECLIA -3, r2 = 0.60, n = 153). The correlation between monoclonal Roche ECLIA and LCMSMS in these samples was very poor (monoclonal ECLIA = 0.31 x LCMSMS + 23, r2 = 0.27).

Conclusions: At the time of its removal from the market, the Roche Elecsys Vitamin D3 (25OH) assay showed unacceptable performance, underestimating vitamin D levels. It seems that this bias preceded the introduction of the monoclonal assay. The worldwide distribution of the assay and the duration of this bias likely led to a significant number of patients starting supplementation unnecessarily.

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Background</b> Inadequate sun exposure and dietary vitamin D intake can result in vitamin D insufficiency. However, limited data are available on actual vitamin D status and predictors in healthy individuals in different regions and by season.

Methods
We compared vitamin D status [25-hydroxyvitamin D; 25(OH)D] in people < 60 years of age using data from cross-sectional studies of three regions across Australia: southeast Queensland (27&deg;S; 167 females and 211 males), Geelong region (38&deg;S; 561 females), and Tasmania (43&deg;S; 432 females and 298 males).

Results
The prevalence of vitamin D insufficiency (≤ 50 nmol/L) in women in winter/spring was 40.5% in southeast Queensland, 37.4% in the Geelong region, and 67.3% in Tasmania. Season, simulated maximum daily duration of vitamin D synthesis, and vitamin D effective daily dose each explained around 14% of the variation in 25(OH)D. Although latitude explained only 3.9% of the variation, a decrease in average 25(OH)D of 1.0 (95% confidence interval, 0.7&ndash;1.3) nmol/L for every degree increase in latitude may be clinically relevant. In some months, we found a high insufficiency or even deficiency when sun exposure protection would be recommended on the basis of the simulated ultraviolet index.

Conclusion Vitamin D insufficiency is common over a wide latitude range in Australia. Season appears to be more important than latitude, but both accounted for less than one-fifth of the variation in serum 25(OH)D levels, highlighting the importance of behavioral factors. Current sun exposure guidelines do not seem to fully prevent vitamin D insufficiency, and consideration should be given to their modification or to pursuing other means to achieve vitamin D adequacy.