916 resultados para Asparosides A And B


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Vascular insufficiency and retinal ischaemia precede many proliferative retinopathies and stimulate secretion of vasoactive growth factors. Vascular endothelial growth factor (VEGF) plays a major role and we therefore investigated the other members of the VEGF family: Placental growth factor (PlGF), VEGF-B, -C, and -D, and platelet derived growth factors (PDGF) A and B. Neonatal mice were exposed to hyperoxia for 5 days and then returned to room air (resulting in acute retinal ischaemia). RT-PCR demonstrated that all the members of the VEGF family are expressed in the retina and in situ hybridization (ISH) located their mRNAs primarily in ganglion cells. Similarly to VEGF itself, VEGF-C, PDGF-A, and PDGF-B were upregulated during retinal ischaemia (P < 0.05). Only PlGF gene expression increased during hyperoxia (P < 0.01). The expression pattern of these growth factors suggests a role in the normal retina and during vaso-obliterative and ischaemic phases.

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We present an analysis of interstellar NaI (lambda(air) = 3302.37 and 3302.98 angstrom), TiII (lambda(air) = 3383.76 angstrom) and CaII K (lambda(air) = 3933.66 angstrom) absorption features for 74 sightlines towards O- and B-type stars in the Galactic disc. The data were obtained from the Ultraviolet and Visual Echelle Spectrograph Paranal Observatory Project, at a spectral resolution of 3.75 km s(-1) and with mean signal-to-noise ratios per pixel of 260, 300 and 430 for the NaI, TiII and CaII observations, respectively. Interstellar features were detected in all but one of the TiII sightlines and all of the CaII sightlines. The dependence of the column density of these three species with distance, height relative to the Galactic plane, HI column density, reddening and depletion relative to the solar abundance has been investigated. We also examine the accuracy of using the NaI column density as an indicator of that for HI. In general, we find similar strong correlations for both Ti and Ca, and weaker correlations for Na. Our results confirm the general belief that Ti and Ca occur in the same regions of the interstellar medium ( ISM) and also that the TiII/CaII ratio is constant over all parameters. We hence conclude that the absorption properties of Ti and Ca are essentially constant under the general ISM conditions of the Galactic disc.

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High-precision correlation of palaeoclimatic and palaeoenvironmental records is crucial for testing hypotheses of synchronous change. Although radiocarbon is the traditional method for dating late Quaternary sedimentary sequences, particularly during the last glacial–interglacial transition (LGIT; 15–9?ka), there are inherent problems with the method, particularly during periods of climate change which are often accompanied by major perturbations in atmospheric radiocarbon content. An alternative method is the use of tephras that act as time-parallel marker horizons. Within Europe, numerous volcanic centres are known to have erupted during the LGIT, providing considerable potential for high-precision correlation independent of past radiocarbon fluctuations. Here we report the first identification of the Vedde Ash and Askja Tephra in Ireland, significantly extending the known provenance of these events. We have also identified two new horizons (the Roddans Port Tephras A and B) and tentatively recognise an additional horizon from Vallensgård Mose (Denmark) that provide crucial additional chronological control for the LGIT. Two phases of the Laacher See Tephra (LST) are reported, the lower Laacher See Tephra (LLST) and probably the C2 phase of the Middle Laacher See Tephra (MLST-C2) indicating a more northeasterly distribution of this fan than reported previously.

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Spectroscopic analyses of 7 SMC B-type supergiants and 1 giant have been undertaken using high resolution optical data obtained on the VLT with UVES. FASTWIND, a non-LTE, spherical, line-blanketed model atmosphere code was used to derive atmospheric and wind parameters of these stars as well as their absolute abundances. Mass-loss rates, derived from H-alpha profiles, are in poor agreement with metallicity dependent theoretical predictions. Indeed the wind-momenta of the SMC stars appear to be in good agreement with the wind-momentum luminosity relationship (WLR) of Galactic B-type stars, a puzzling result given that line-driven wind theory predicts a metallicity dependence. However the galactic stars were analysed using unblanketed model atmospheres which may mask any dependence on metallicity. A mean nitrogen enhancement of a factor of 14 is observed in the supergiants whilst only an enrichment of a factor of 4 is present in the giant, AV216. Similar excesses in nitrogen are observed in O-type dwarfs and supergiants in the same mass range, suggesting that the additional nitrogen is produced while the stars are still on the main-sequence. These nitrogen enrichments can be reproduced by current stellar evolution models, which include rotationally induced mixing, only if large initial rotational velocities of 300 kin s(-1) are invoked. Such large rotational velocities appear to be inconsistent with observed v sin i distributions for O-type stars and B-type supergiants. Hence it is suggested that the currently available stellar evolution models require more efficient mixing for lower rotational velocities.

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The applicability of density functional (DF) methods has progressed greatly since the first workshop of this series ten years ago. Applications that show both the successes and the limitations can be found in the fields of: (a) the structures of the isomers of atomic clusters. and (b) the structure of organic molecules and polymers, and their reactions with additional molecules. We shall review some of the results and the lessons to be learned from them. (C) 2001 Elsevier Science B.V. All rights reserved.

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Charge exchange followed by radiative stabilization are the main processes responsible for the recent observations of X-ray emission from comets in their approach to the Sun. A new apparatus was constructed at JPL to measure, in collisions of HCIs with atoms and molecules, (a) absolute cross sections for single and multiple charge exchange, and (b) normalized X-ray emission cross sections. The ions are produced by the JPL HCI Facility and passed through a neutral-gas target cell. The product charge states are analyzed by a retarding potential difference technique. Results are made absolute by measuring target pressure, and incident and product ion currents. X-rays emitted from the product ions are detected with a Ge solid-state detector having a resolution of approximately 100 eV. X-ray astronomy has taken major steps forward with the recent launch of the high-resolution satellites Chandra and Newton. The cross sections reported herein are essential for the development of the solar wind comet interaction models inspired by these observations.

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Coleoid cephalopods show flexibility in their reproductive strategies or mode of spawning, which can range from simultaneous terminal spawning over a short period at the end of the animal’s life to continuous spawning over a long period of the animal’s life. Although a simultaneous terminal spawning strategy is typical of shallow water temperate octopuses, it is not known whether deep-sea octopods would have the same reproductive strategy. The reproductive strategies and fecundity were investigated in nine species of deep-sea incirrate octopuses: Bathypolypus arcticus, Bathypolypus bairdii, Bathypolypus ergasticus, Bathypolypus sponsalis, Bathypolypus valdiviae, Benthoctopus levis, Benthoctopus normani, Benthoctopus sp., and Graneledone verrucosa (total n = 85). Egg-length frequency graphs and multivariate analysis (principal components analysis) suggest that B. sponsalis has a synchronous ovulation pattern and therefore a simultaneous terminal spawning strategy. Although a simultaneous terminal spawning strategy is most likely for B. levis and B. normani, the egg-length frequency graphs and multivariate analysis also suggest a greater variation in egglengths which could lead to spawning over an extended period.

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Investigations of queen, worker and male bumble bees (Bombus terrestris) showed that all individuals became infected with Nosema bombi. Infections were found in Malpighian tubules, thorax muscles, fat body tissue and nerve tissue, including the brain. Ultrastructural studies revealed thin walled emptied spores in host cell cytoplasm interpreted as autoinfective spores, besides normal spores (environmental spores) intended for parasite transmission between hosts. The nucleotide sequence of the gene coding for the small subunit rRNA (SSU-rRNA) from Microsporidia isolated from B. terrestris, B. lucorum, and B. hortorum were identical, providing evidence that N. bombi infects multiple hosts. The sequence presented here (GenBank Accession no AY008373) is different from an earlier submission to GenBank (Accession no U26158) of a partial sequence of the same gene based on material collected from B. terrestris. It still remains to be investigated if there is species diversity among Microsporidia found in bumble bees.

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Aqueous extracts were prepared from five barley crystal malts (color range 15-440 degrees EBC, European Brewing Convention units). Antioxidant activity was determined by using the 2,2'-azinobis(3-ethylbenothiazoline-6-sulfonic acid) (ABTS(.+)) radical cation scavenging method. Antioxidant activity increased with increasing color value although the rate of increase decreased with increasing color value. Color was measured in CIELAB space. Extracts of the 15, 23, and 72 degrees EBC malts followed the same dilution pathway as did the 148 degrees EBC sample at higher dilution levels, indicating that they could each be used to give the same color by appropriate dilution. The 440 degrees EBC sample followed a different dilution pathway, indicating that different compounds were responsible for color in this extract. Fifteen selected volatile compounds were monitored using gas chromatography/mass spectrometry (GC/MS). Levels of methylpropanal, 2-methylbutanal, and 3-methylbutanal were highest for the 72 degrees EBC sample. When odor threshold values of the selected compounds were taken into account, 3-methylbutanal was the most important contributor to flavor., Relationships between levels of the lipid oxidation products, hexanal and (E)-2-nonenal, and antioxidant activity were complex, and increasing antioxidant activity for samples in the range of 15-148 degrees EBC did-not result in reduced levels of these lipid-derived compounds. When different colored malt extracts were diluted to give the same a* and b* values, calculated antioxidant activity and amounts of 3-methylbutanal, hexanal, and (E)-2-nonenal decreased with increasing degrees EBC value.

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Dojoji Temple ( Dōjōji, 1976) is a short puppet animation directed by Kihachirō Kawamoto. Influenced by Bunraku (Japanese puppet plays), emaki (painted scroll), Noh theatre and Japanese myth, Dojoji Temple tells of a woman’s unrequited love for a young priest. Heartbroken, she then transforms into a sea serpent and goes after the priest for revenge. While Kawamoto’s animation is rich with Japanese aesthetics and tragedy, his animation is peopled by puppets who do not speak. Limited and restrained though the puppets may be, their animated gestures speak volumes of powerful emotions. For our article, we will select several scenes from the animation, and interpret their actions so that we can further understand the mythical world of Dojoji Temple and the essential being of puppetry. Our gesture analysis will take into account cinematographic compositions, sound and bodily attires, among other elements.

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OBJECTIVE:<br/><br/>To compare the performance of patients with mild-moderate Alzheimer's disease (AD) and vascular dementia (VaD) on tests of information processing and attention.<br/><br/>METHOD:<br/><br/>Patients with AD (n=75) and VaD (n=46) were recruited from a memory clinic along with dementia-free participants (n=28). They underwent specific tests of attention from the Cognitive Drug Research battery, and pen and paper tests including Colour Trails A and B and Stroop. All patients had a CT brain scan that was independently scored for white-matter change/ischaemia.<br/><br/>RESULTS:<br/><br/>Attention was impaired in both AD and VaD patients. VaD patients had more impaired choice reaction times and were less accurate on a vigilance test measuring sustained attention. Deficits in selective and divided attention occurred in both patient groups and showed the strongest correlations with Mini Mental State Examination scores.<br/><br/>CONCLUSION:<br/><br/>This study demonstrates problems with the attentional network in mild-moderate AD and VaD. The authors propose that attention should be tested routinely in a memory clinic setting.

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An in vitro method of determining the activity of antibiotics in combination which is simple and convenient to perform and which could be used routinely in clinical microbiology laboratories is desirable. We investigated the activity, against Pseudomonas aeruginosa and Burkholderia cepacia complex clinical isolates, of ceftazidime and tobramycin in combination using a broth macrodilution sensitivity method based on breakpoint minimum inhibitory concentrations and compared the results obtained using this method with those obtained using the microtitre checkerboard method. There was good agreement in interpretation of results between the two methods for both P. aeruginosa (90%) and B. cepacia complex isolates (70%) with tobramycin and for P. aeruginosa isolates (70%) with ceftazidime. As the breakpoint combination sensitivity testing method employs only four tubes and does not require initial determination of individual antibiotic minimum inhibitory concentrations, it is simpler and more convenient for determining the activity of antibiotics in combination than the microtitre checkerboard method. The use of this method in routine microbiology laboratories to determine the activity of antibiotic combinations against clinical isolates should optimise treatment of infection by ensuring that appropriate antibiotic combinations are prescribed. (C) 2004 Elsevier B.V. All rights reserved.

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Having a child diagnosed with Autism Spectrum Disorder (ASD) poses a range of challenges to families, many of which can be addressed through appropriate intervention. A study of parental (n = 95) and professional (n = 67) experiences was carried out in relation to two settings: (a) schools that provided intensive interventions based on the science of Applied Behavior Analysis (ABA), and (b) non-intensive ABA-based home programs. Results show that parents whose children attend ABA-based schools were generally more satisfied with their child's educational provision, monitoring procedures, and level of staff training, than parents who were not offered ABA-based education in schools. © 2012 Copyright Taylor and Francis Group, LLC.

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Previous studies have shown that glycation of insulin occurs in pancreatic beta -cells under conditions of hyperglycaemia and that the site of glycation is the N-terminal Phe(1) of the insulin B-chain. To enable evaluation of glycated insulin in diabetes, specific antibodies were raised in rabbits and guinea-pigs by using two synthetic peptides (A: Phe-Val-Asn-Gln-His-Leu-Cys-Tyr, and B: Phe-Val-Asn-Gln-His-Leu-Tyr-Lys) modified by N-terminal glycation and corresponding closely to the N-terminal sequence of the glycated human insulin B-chain. For immunization, the glycated peptides were conjugated either to keyhole limper haemocyanin or ovalbumin using glutaraldehyde, m-maleimidobenzoyl-N-hydroxysuccinimide ester or 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride. Antibody titration curves, obtained using I-125-tyrosylated tracer prepared from glycated peptide A, revealed high-titre antisera in five groups of animals immunized for 8-28 weeks. The highest titres were observed in rabbits and guinea-pigs immunized with peptide B coupled to ovalbumin using glutaraldehyde. Under radioimmunoassay conditions, these antisera exhibited effective dose (median) (ED50) values for glycated insulin of 0.3-15 ng/ml and 0.9-2.5 ng/ml respectively, with negligible cross-reactivity against insulin or other islet peptides. The degree of cross-reaction with glycated proinsulin was approximately 50%. Glycated insulin in plasma of control and hydrocortisone-treated diabetic rats measured using rabbit 3 antiserum (1:10 000 dilution; sensitivity

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Formalin fixed and paraffin embedded tissue (FFPE) collections in pathology departments are the largest resource for retrospective biomedical research studies. Based on the literature analysis of FFPE related research, as well as our own technical validation, we present the Translational Research Arrays (TRARESA), a tissue microarray centred, hospital based, translational research conceptual framework for both validation and/or discovery of novel biomarkers. TRARESA incorporates the analysis of protein, DNA and RNA in the same samples, correlating with clinical and pathological parameters from each case, and allowing (a) the confirmation of new biomarkers, disease hypotheses and drug targets, and (b) the postulation of novel hypotheses on disease mechanisms and drug targets based on known biomarkers. While presenting TRARESA, we illustrate the use of such a comprehensive approach. The conceptualisation of the role of FFPE-based studies in translational research allows the utilisation of this commodity, and adds to the hypothesis-generating armamentarium of existing high-throughput technologies.