32 resultados para anomalous Eu3 5D0->F-7(0) transition

em University of Queensland eSpace - Australia


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Objective. Outcome assessment in clinical trials using the Western Ontario and McMaster University (WOMAC 3.0) Osteoarthritis Index is traditionally achieved through self-administration of the Index. However, in other areas of clinical measurement, telephone administration has been shown to be a reliable method of acquiring data that are both accurate and complete. To address this issue in knee osteoarthritis (OA), we conducted a comparative study of telephone administration by interviewer of WOMAC LK3.0 versus onsite self-completion at the hospital. Methods. Fifty consenting patients with knee OA were randomized to complete the WOMAC LK3.0 Index by telephone interview one day, followed by onsite completion the following day, or vice versa. Neither patients nor interviewers had access to any prior scores. Results. The mean age of the 50 patients was 66.3 years (range 44-82); 34 (68%) were female and 16 (32%) male. There was excellent agreement between the mean office and telephone scores, with mean differences for the WOMAC LK3.0 pain, stiffness, and function subscale scores and total score of 0.09, 0.12, 0.78, and 0.98, respectively. These differences were well within the respective protocol defined equivalence criteria of +/- 1.7, +/- 0.9, +/- 6.4, and +/- 9.1, and represented differences from office scores of 0.9, 2.6, 2.4, and 2.2%, respectively. Conclusion. The use of telephone interviews for the WOMAC LK3.0 Index is a valid method of obtaining OA outcome measurements. These observations have important implications for designing data acquisition strategies for future OA clinical trials and for longterm observational studies.

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The Hubble Deep Field South (HDF-S) Hubble Space Telescope (HST) observations are expected to begin in 1998 October. We present a composite spectrum of the QSO in the HDF-S held covering UV/optical/near-IR wavelengths, obtained by combining data from the Australian National University 2.3 m telescope with STIS on the HST.(1) This intermediate-resolution spectrum covers the range 1600-10000 Angstrom and allows us to derive some basic information on the intervening absorption systems which will be important in planning future higher resolution studies of this QSO. The QSO J2233 - 606 coordinates are alpha = 22(h)33(m)37(s).6, delta = -60 degrees 33'29 (J2000), the magnitude is B = 17.5, and its redshift is z(em) = 2.238, derived by simultaneously fitting several emission lines. The spectral index is alpha = -0.7 +/- 0.1, measured between the Ly alpha and Mg II emission lines. Many absorption systems are present, including systems with metal lines redward of the Ly alpha emission line at z(abs) 2.204, 1.942, 1.870, 1.787 and a few very strong Ly alpha features at z(abs) = 2.077, 1.928, without similarly strong metal lines. There is a conspicuous Lyman limit (LL) absorption system that is most likely associated with the z(abs) = 1.942 system with a neutral hydrogen column density of N-HI = (3.1 +/- 1.0) x 10(17) cm(-2). There is some evidence for the presence of a second LL absorber just to the blue of the conspicuous system at z = 1.870. We have employed a new technique, based on an analysis of the shape of the observed spectrum in the region of the LL absorption, to explore the properties of the gas. We tentatively conclude that this system might have suitable characteristics for measuring the deuterium-to-hydrogen (D/H) ratio.

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Motivation: Prediction methods for identifying binding peptides could minimize the number of peptides required to be synthesized and assayed, and thereby facilitate the identification of potential T-cell epitopes. We developed a bioinformatic method for the prediction of peptide binding to MHC class II molecules. Results: Experimental binding data and expert knowledge of anchor positions and binding motifs were combined with an evolutionary algorithm (EA) and an artificial neural network (ANN): binding data extraction --> peptide alignment --> ANN training and classification. This method, termed PERUN, was implemented for the prediction of peptides that bind to HLA-DR4(B1*0401). The respective positive predictive values of PERUN predictions of high-, moderate-, low- and zero-affinity binder-a were assessed as 0.8, 0.7, 0.5 and 0.8 by cross-validation, and 1.0, 0.8, 0.3 and 0.7 by experimental binding. This illustrates the synergy between experimentation and computer modeling, and its application to the identification of potential immunotheraaeutic peptides.

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1 We identified putative beta(4)-adrenoceptors by radioligand binding, measured increases in ventricular contractile force by (-)-CGP 12177 and (+/-)-cyanopindolol and demonstrated increased Ca2+ transients by (-)-CGP 12177 in rat cardiomyocytes. 2 (-)-[H-3]-CGP 12177 labelled 13-22 fmol mg(-1) protein ventricular beta(1), beta(2)-adrenoceptors (pK(D) similar to 9.0) and 50-90 fmol mg(-1) protein putative beta(4)-adrenoceptors (pK(D) similar to 7.3). The affinity values (PKi) for (beta(1),beta(2)-) and putative beta(4)-adrenoceptors, estimated from binding inhibition, were (-)-propranolol 8.4, 5.7; (-)-bupranolol 9.7, 5.8; (+/-)-cyanopindolol 10.0,7.4. 3 In left ventricular papillary muscle, in the presence of 30 mu M 3-isobutyl-1-methylxanthine, (-)CGP 12177 and (+/-)-cyanopindolol caused positive inotropic effects, (pEC(50) (-)-CGP 12177, 7.6; (+/-)-cyanopindolol, 7.0) which were antagonized by (-)-bupranolol (pK(B) 6.7-7.0) and (-)-CGP 20712A (pK(B) 6.3-6.6). The cardiostimulant effects of(-)-CGP 12177 in papillary muscle, left and right atrium were antagonized by (+/-)-cyanopindolol (pK(i), 7.0-7.4). 4 (-)-CGP 12177 (1 mu M) in the presence of 200 nM (-)-propranolol increased Ca2+ transient amplitude by 56% in atrial myocytes, but only caused a marginal increase in ventricular myocytes. In the presence of 1 mu M 3-isobutyl-1-methylxanthine and 200 nM (-)-propranolol, 1 mu M (-)-CGP 12177 caused a 73% increase in Ca2+ transient amplitude in ventricular myocytes. (-)-CGP 12177 elicited arrhythmic transients in some atrial and ventricular myocytes. 5 Probably by preventing cyclic AMP hydrolysis, 3-isobutyl-1-methylxanthine facilitates the inotropic function of ventricular putative beta(4)-adrenoceptors. suggesting coupling to G(s) protein-adenylyl cyclase. The receptor-mediated increases in contractile force are related to increases of Ca2+ in atrial and ventricular myocytes. The agreement of binding affinities of agonists with cardiostimulant potencies is consistent with mediation through putative beta(4)-adrenoceptors labelled with (-)-[H-3]-CGP 12177.

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The aim of this study was to establish the effect that pre-cooling the skin without a concomitant reduction in core temperature has on subsequent self-paced cycling performance under warm humid (31 degrees C and 60% relative humidity) conditions. Seven moderately trained males performed a 30 min self-paced cycling trial on two separate occasions. The conditions were counterbalanced as control or whole-body pre-cooling by water immersion so that resting skin temperature was reduced by approximate to 5-6 degrees C. After pre-cooling, mean skin temperature was lower throughout exercise and rectal temperature was lower (P < 0.05) between 15 and 25 min of exercise. Consequently, heat storage increased (P < 0.003) from 84.0 +/- 8.8 W . m(-2) to 153 +/- 13.1 W . m(-2) (mean +/- s((x) over bar)) after pre-cooling, while total body sweat fell from 1.7 +/- 0.1 1 . h(-1) to 1.2 +/- 0.1 1 . h(-1) (P < 0.05). The distance cycled increased from 14.9 +/- 0.8 to 15.8 +/- 0.7 km (P < 0.05) after pre-cooling. The results indicate that skin pre-cooling in the absence of a reduced rectal temperature is effective in reducing thermal strain and increasing the distance cycled in 30 min under warm humid conditions.

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We have developed a novel inhibitor of the metalloendopeptidases EC 3.4.24.15 (EP24.15) and EC 3.4.24.16 (EP24.16), N-[1-(R, S)-carboxy-3-phenylpropyl]-Ala-Aib-Tyr-p-aminobenzoate (JA2), in which alpha-aminoisobutyric acid (Aib) is substituted for an alanine in a well-described but unstable inhibitor, cFP-AAY-pAB. This substitution increases the resistance of the inhibitor to degradation without altering potency. In the present study, we investigated the effects of JA2 (5 mg/kg) on the responses of mean arterial pressure to bradykinin, angiotensin I, and angiotensin II in conscious rabbits. The depressor responses to both low (10 ng/kg) and high (100 ng/kg) doses of bradykinin were increased 7.0 +/- 2.7-fold and 1.5 +/- 0.3-fold, respectively, during the 30 minutes after JA2 administration (mean+/-SEM, n=8). Bradykinin potentiation was undiminished 4 hours after JA2 injection. In contrast, the hypertensive effects of angiotensins I and II were unaltered, indicating that the bradykinin-potentiating effects were not due to angiotensin-converting enzyme inhibition. These data suggest that JA2 is not only a potent and specific inhibitor of EP24.15 and EP24.16 but is also stable in vivo. Furthermore, the potentiation of bradykinin-induced hypotension by JA2 suggests for the first time a role for one or both of these peptidases in the metabolism of bradykinin in the circulation.

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2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) is one of several mutagenic and carcinogenic heterocyclic amines formed during the cooking process of protein-rich foods, These compounds are highly mutagenic and have been shown to produce tumours in various tissues in rodents and non-human primates. Metabolic activation of IQ is a two-step process involving N-hydroxylation by CYP1A2 followed by esterification to a more reactive species capable of forming adducts with DNA, To date, acetylation and sulphation have been proposed as important pathways in the formation of N-hydroxy esters, In this study we have demonstrated the presence of an ATP-dependent activation pathway for N-hydroxy-IQ (N-OH-IQ) leading to DNA adduct formation measured by covalent binding of [H-3]N-OH-IQ to DNA, ATP-dependent DNA binding of N-OH-IQ was greatest in the cytosolic fraction of rat liver, although significant activity was also seen in colon, pancreas and lung. ATP was able to activate N-OH-IQ almost 10 times faster than N-hydroxy-2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (7.7 +/- 0.3 and 0.9 +/- 0.1 pmol/mg protein/min, respectively). Using reported intracellular concentrations of cofactor, the ability of ATP to support DNA binding was similar to that seen with 3'-phosphoadenosine 5'-phosphosulphate and similar to 50% of that seen with acetyl coenzyme A (AcCoA), In addition to DNA binding, HPLC analysis of the reaction mixtures using ATP as co-factor showed the presence of two stable, polar metabolites, With AcCoA, only one metabolite was seen. The kinase inhibitors genistein, tyrphostin A25 and rottlerin significantly inhibited both DNA binding and metabolite formation with ATP. However, inhibition was unlikely to be due to effects on enzyme activity since the broad spectrum kinase inhibitor staurosporine had no effect and the inactive analogue of genistein, daidzein, was as potent as genistein, The effects of genistein and daidzein, which are naturally occurring isoflavones from soy and other food products, on DNA adduct formation may potentially be useful in the prevention of heterocyclic amine-induced carcinogenesis.

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Background-In adult human heart, both beta(1)- and beta(2)-adrenergic receptors mediate hastening of relaxation; however, it is unknown whether this also occurs in infant heart. We compared the effects of stimulation of beta(1)- and beta(2)-adrenergic receptors on relaxation and phosphorylation of phospholamban and troponin I in ventricle obtained from infants with tetralogy of Fallot. Methods and Results-Myocardium dissected from the right ventricular outflow tract of 27 infants (age range 2-1/2 to 35 months) with tetralogy of Fallot was set up to contract 60 times per minute. Selective stimulation of beta(1)-adrenergic receptors with (-)-norepinephrine (NE) and beta(2)-adrenergic receptors with (-)-epinephrine (EPI) evoked phosphorylation of phospholamban (at serine-16 and threonine-17) and troponin I and caused concentration-dependent increases in contractile force (-log EC50 [mol/L] NE 5.5+/-0.1, n=12; -EPI 5.6+/-0.1, n=13 patients), hastening of the time to reach peak force (-log EC50 [mol/L] NE 5.8+/--0.2; EPI 5.8+/-0.2) and 50% relaxation (-log EC50 [mol/L] NE 5.7+/-0.2: EPI 5.8+/-0.1), Ventricular membranes from Fallot infants, labeled with (-)-[I-125]-cyanopindolol, revealed a greater percentage of beta(1)- (71%) than beta(2)-adrenergic receptors (29%). Binding of (-)-epinephrine to beta(2)-receptors underwent greater GTP shifts than binding of (-)-norepinephrine to beta(1)-receptors. Conclusions-Despite their low density, beta(2)-adrenergic receptors are nearly as effective as beta(1)-adrenergic receptors of infant Fallot ventricle in enhancing contraction, relaxation, and phosphorylation of phospholamban and troponin I, consistent with selective coupling to G(s)-protein.

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DNA that enters the circulation is rapidly cleared both by tissue uptake and by DNase-mediated degradation. In this study, we have examined the uptake of linear plasmid DNA in an isolated perfused liver model and following intra-arterial administration to rats. We found that the DNA was rapidly taken up by the isolated perfused liver without degradation. The single-pass extraction ratio was 0.76 +/- 0.05, the mean transit time was 15.3 +/- 3.6 s, and the volume of distribution was 0.29 +/- 0.07 ml/g. Hepatic uptake was saturable and was inhibited by polyinosinic acid or polycationic liposomes but not by condensation of the DNA with polylysine. When the linear plasmid DNA was administered in vivo, plasma half-life was 3.1 +/- 0.2 min, volume of distribution was 670 +/- 85 ml/kg, and clearance was 32 +/- 4 min. Coadministration of cationic liposomes decreased the volume of distribution to 180 +/- 28 ml/kg as well as the half-life (2.6 +/- 0.2 min). By contrast, polyinosinic acid significantly increased the circulating half-life (7.7 +/- 0.5 min), decreased the volume of distribution (95 +/- 17 ml/kg), and partially inhibited DNA degradation. When administered along with the liposomes and the polyinosinic acid, the distribution of plasmid-derived radioactivity decreased in the liver and increased in most other peripheral tissues. This study shows that pharmacological manipulation of the uptake and degradation of DNA can alter its distribution and clearance in vivo. These results may be useful in optimizing gene delivery procedures for in vivo gene therapy.

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A representative sample (n = 10 641) of Australian adults completed a structured diagnostic interview assessing the prevalence of mental and substance use disorders in the last year. The prevalence of DSM-IV (1.5%) and ICD-10 (1.7%) cannabis dependence was similar. DSM-IV and ICD-10 dependence criteria comprised unidimensional syndromes. The most common symptoms among dependent and non-dependent users were difficulties with controlling use and withdrawal, although there were marked differences in symptom prevalence. Dependent users reported a median of four symptoms. There was good to excellent diagnostic concordance (kappas = 0.7-0.9) between systems for dependence but not for abuse/harmful use (Y = 0.4). These findings provide some support for the validity of cannabis dependence. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

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in Escherichia coli, the DnaG primase is the RNA polymerase that synthesizes RNA primers at replication forks. It is composed of three domains, a small N-terminal zinc-binding domain, a larger central domain responsible for RNA synthesis, and a C-terminal domain comprising residues 434-581 [DnaG(434-581)] that interact with the hexameric DnaB helicase. Presumably because of this interaction, it had not been possible previously to express the C-terminal domain in a stably transformed E coli strain. This problem was overcome by expression of DnaG(434-581) under control of tandem bacteriophage gimel-promoters, and the protein was purified in yields of 4-6 mg/L of culture and studied by NMR. A TOCSY spectrum of a 2 mM solution of the protein at pH 7.0, indicated that its structured core comprises residues 444-579. This was consistent with sequence conservation among most-closely related primases. Linewidths in a NOESY spectrum of a 0.5 mM sample in 10 mM phosphate, pH 6.05, 0.1 M NaCl, recorded at 36 degreesC, indicated the protein to be monomeric. Crystals of selenomethionine-substituted DnaG(434-581) obtained by the hanging-drop vapor-diffusion method were body-centered tetragonal, space group I4(1)22, with unit cell parameters a = b 142.2 Angstrom, c = 192.1 Angstrom, and diffracted beyond 2.7 Angstrom resolution with synchrotron radiation. (C) 2003 Elsevier Inc. All rights reserved.

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Inorganic nutrients play a critical role in determining benthic community structure in tropical seas. This study examined the impact of adding inorganic nutrients (ammonium and phosphate) on the isotopic composition of 2 reef-building corals, Pocillopora damicornis and Heliofungia actiniformis, on the southern Great Barrier Reef. The addition of elevated nutrients to patch reefs that pond at low tide did not perturb the C:N ratio of either species or their symbiotic dinoflagellates. The C:N ratios were significantly higher in material extracted from the skeleton (14.8 +/- 1.50 and 10.8 +/- 1.42) than either host (7.6 +/- 0.87 and 6.0 +/- 0.71) or symbiotic dinoflagellates (5.7 +/- 0.48 and 6.9 +/- 0.66) (P. damicornis and H. actiniformis respectively; 95 confidence intervals). The ratio of acquired N to background N suggests that the added dissolved inorganic nitrogen (DIN) accounted for 50 to 100% of total nitrogen within the tissues of P. damicornis and H. actiniformis at the end of the experiment. The addition of the isotopically depleted nutrients (delta(15) N = 0parts per thousand) to patch reefs significantly decreased delta(15)N from control values of between 3 and 4 to values to below 1 in the case of all compartments, while delta(13)C values were relatively unresponsive to nutrient treatments. These findings suggest that coral delta(15)N has the potential to provide a historical record of the delta(15)N of dissolved nitrogen surrounding reef-building corals and their symbiotic dinoflagellates.

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The total deposition of environmental tobacco smoke (ETS), diesel and petrol smoke in the respiratory tract of 14 non-smokers between the ages of 20 and 30 was determined experimentally. A scanning mobility particle sizer (SMPS) measuring a size range of 0.016-0.626 mu m was used to characterise the inhaled and exhaled aerosol during relaxed nasal breathing over a period of 10 min. The ETS, diesel, and petrol particles had average count median diameter (and geometric standard deviation) of 0.183 mu m (1.7), 0.125 mu m (1.7), and 0.069 mu m (1.7), respectively. The average total number deposition of ETS was 36% (standard deviation 10%), of diesel smoke 30% (standard deviation 9%), and of petrol smoke 41% (standard deviation 8%). The analysis of the deposition patterns as a function of particle size for the three aerosols in each individual showed that there is a significant difference between each aerosol for a majority of individuals (12 out of 14). This is an important result as it indicates that differences persist regardless of inter-subject variability. (C) 2005 Elsevier Ltd. All rights reserved.

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Chronic asthma is characterized by airway inflammation, mucus hypersecretion and impaired mucociliary clearance (MCC). We investigated baseline MCC and the acute effect of terbutaline in chronic asthmatics with sputum production while on long-term treatment with salmeterol in combination with inhaled corticosteroids (ICS). MCC was measured at baseline and in response to 1 mg terbutaline (or placebo) on three visits over 80 min in 16 asthmatics (52 +/- 13 years of age). Subjects who had greater than 10% absolute increase in MCC above baseline and placebo, after terbutaline, were categorized in group A and subjects who had less than 10% in group B. In group A subjects (n = 6), MCC increased from 23.7 +/- 4.0% at baseline to 43.7 +/- 4.9% with terbutaline (P < 0.0001) and to 34.4 +/- 5.7% with placebo (P < 0.01). In group B subjects (n = 10), MCC remained similar: 11.3 +/- 3.2% at initial baseline, 12.0 +/- 3.2% with terbutaline and 7.3 +/- 3.0% with placebo (P > 0.05). Group B subjects withdrew from all beta(2) agonists for a week and MCC was remeasured. After withdrawal, baseline MCC (7.0 +/- 1.8%) was similar to the initial baseline value (P > 0.1) and MCC with terbutaline (15.8 +/- 4.9%) was greater than baseline (P < 0.005) but remained abnormal in most subjects. Baseline percentage predicted FEV1 and FEF25-75% were 77.3 +/- 7.2 and 41.7 +/- 5.6 in group A and 59.9 +/- 8.1 and 29.5 +/- 8.4 in group B subjects, respectively. MCC was impaired in most of these asthmatics with persistent airway obstruction and sputum production, despite regular treatment with ICS and salmeterol. In addition, there was little or no stimulation of MCC acutely after terbutaline in most of these asthmatics.

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Ovaries (n = 140) from 70 mixed-age multiparous, lactating Brahman cross (3/4-7/8 Bos indicus) cows were used to examine the hypothesis that counts of follicles visible on the surface of the ovaries of Bos indicus cows and their classification into diameter size classes, are closely correlated with numbers of follicles in those size classes found by complete dissection of the ovary. immediately after ovariectomy, mean diameters (long and short axes averaged) of all follicles greater than or equal to 2 mm visible on the surface of each ovary were measured. All follicles greater than or equal to 2 mm were dissected from the ovaries, excess stroma removed and follicle diameters measured under a stereomicroscope using an ocular graticule. For each ovary, follicles were classified in either small (8 mm) categories based on either diameters of surface or dissected follicles. Data for numbers of surface and dissected follicles (mean +/- SE) in small, medium, large categories and total follicle numbers, respectively, were 24.4 +/- 1.6 vs. 28.0 +/- 1.9, 1.6 +/- + 0.2 vs. 11.6 +/- 1.0, 0.5 +/- 0.1 vs. 0.7 +/- 0.1 and 26.4 +/- 1.6 vs. 40.4 +/- 2.5. Correlation coefficients (r) for counts of surface and dissected follicles in small, medium, large and total follicle numbers were 0.76, 0.40, 0.69 and 0.79, respectively. Medium size follicles presented only a small translucent area on the surface of the ovary, leading to an underestimate of numbers when categorised by surface evaluation. Counts of follicles visible on the surface of the ovaries of Bos indicus cows and their classification into size classes based on estimated diameter, are closely correlated with numbers of follicles in those size classes found at dissection of the ovary for small (8 mm) and total follicles but not for medium sized (4-8 mm) follicles. (C) 1997 Elsevier Science B.V.