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51.
Lóránt Dienes Huba J. Kiss Kristóf Perényi Zsuzsanna Szepessy Zoltán Z. Nagy árpád Barsi M. Carmen Acosta Juana Gallar Illés Kovács 《PloS one》2015,10(8)
Purpose
To investigate the characteristics of ocular surface sensations and corneal sensitivity during the interblink interval before and after tear supplementation in dry eye patients.Methods
Twenty subjects (41.88±14.37 years) with dry eye symptoms were included in the dry eye group. Fourteen subjects (39.13±11.27 years) without any clinical signs and/or symptoms of dry eye were included in the control group. Tear film dynamics was assessed by non-invasive tear film breakup time (NI-BUT) in parallel with continuous recordings of ocular sensations during forced blinking. Corneal sensitivity to selective stimulation of corneal mechano-, cold and chemical receptors was assessed using a gas esthesiometer. All the measurements were made before and 5 min after saline and hydroxypropyl-guar (HP-guar) drops.Results
In dry eye patients the intensity of irritation increased rapidly after the last blink during forced blinking, while in controls there was no alteration in the intensity during the first 10 sec followed by an exponential increase. Irritation scores were significantly higher in dry eye patients throughout the entire interblink interval compared to controls (p<0.004). NI-BUT significantly increased after HP-guar (p = 0.003) but not after saline drops (p = 0.14). In both groups, either after saline or HP-guar the shape of symptom intensity curves remained the same with significantly lower irritation scores (p<0.004), however after HP-guar the decrease was significantly more pronounced (p<0.004). Corneal sensitivity to selective mechanical, cold and chemical stimulation decreased significantly in both groups after HP-guar (p<0.05), but not after saline drops (p>0.05).Conclusion
Ocular surface irritation responses due to tear film drying are considerably increased in dry eye patients compared to normal subjects. Although tear supplementation improves the protective tear film layer, and thus reduce unpleasant sensory responses, the rapid rise in discomfort is still maintained and might be responsible for the remaining complaints of dry eye patients despite the treatment. 相似文献52.
Renan Idalencio Fabiana Kalichak Jo?o Gabriel Santos Rosa Tiago Acosta de Oliveira Gessi Koakoski Darlan Gusso Murilo Sander de Abreu Ana Cristina Varrone Giacomini Heloísa Helena de Alcantara Barcellos Angelo L. Piato Leonardo José Gil Barcellos 《PloS one》2015,10(10)
The presence of drugs and their metabolites in surface waters and municipal effluents has been reported in several studies, but its impacts on aquatic organisms are not yet well understood. This study investigated the effects of acute exposure to the antipsychotic risperidone on the stress and behavioral responses in zebrafish. It became clear that intermediate concentration of risperidone inhibited the hypothalamic-pituitary-interrenal axis and displayed anxiolytic-like effects in zebrafish. The data presented here suggest that the presence of this antipsychotic in aquatic environments can alter neuroendocrine and behavior profiles in zebrafish. 相似文献
53.
54.
Characterization of the novel antifungal chitosanase PgChP and the encoding gene from Penicillium chrysogenum 总被引:1,自引:0,他引:1
Andrea Rodríguez-Martín Raquel Acosta Susan Liddell Félix Núñez María José Benito Miguel A. Asensio 《Applied microbiology and biotechnology》2010,88(2):519-528
The protein PgChP is a new chitosanase produced by Penicillium chrysogenum AS51D that showed antifungal activity against toxigenic molds. Two isoforms were found by SDS-PAGE in the purified extract
of PgChP. After enzymatic deglycosylation, only the smaller isoform was observed by SDS-PAGE. Identical amino acid sequences
were obtained from the two isoforms. Analysis of the molecular mass by electrospray ionization-mass spectrometry revealed
six major peaks from 30 to 31 kDa that are related to different levels of glycosylation. The pgchp gene has 1,146 bp including four introns and an open reading frame encoding a protein of 304 amino acids. The translated
open reading frame has a predicted mass of 32 kDa, with the first 21 amino acids comprising a signal peptide. Two N glycosylation
consensus sequences are present in the protein sequence. The deduced sequence showed high identity with fungal chitosanases.
A high level of catalytic activity on chitosan was observed. PgChP is the first chitosanase described from P. chrysogenum. Given that enzymes produced by this mold species are granted generally recognized as safe status, PgChP could be used as
a food preservative against toxigenic molds and to obtain chitosan oligomers for food additives and nutraceuticals. 相似文献
55.
Teresa Mancilla-Percino José Correa-Basurto José Trujillo-Ferrara Fernando R. Ramos-Morales Mario E. Acosta Hernández Jesús S. Cruz-Sánchez Margarita Saavedra-Vélez 《Journal of molecular modeling》2010,16(8):1377-1382
Two series of isoindolines 1(a–g) and 2(a–g) were found by docking calculations to be possible L-type Ca2+ channel (LCC) blockers. The theoretical 3-D model of the outer vestibule and the selective filter of the LCC was provided
by Professor Lipkind; this model consists of transmembrane segments S5 and S6 and P-loops contributed by each of four repeats
(I, II, III, and IV) of Cav 1.2. Therefore, two well-known LCC blockers, nifedipine 3 and (R)-ethosuccinimide 4 were also evaluated, and their binding sites on the LCC were identified and compared with those obtained for 1(a–g) and 2(a–g). Analysis of the results shows that the target compounds tested probably could be LCC blockers, since they interact with
or near the glutamic acid residues Glu393, Glu736, Glu1145 and Glu1446 (the EEEE locus), which belong to the LCC selectivity
region. The ∆G values for all of the Ca2+ channel ligands are between−10.78 and −3.67 (kcal mol−1), showing that LCC-1b, -1e and -1f complexes are more stable than the other compounds tested. Therefore, theoretically calculated dissociation constants K
d (μM) were obtained for all compounds. Comparing these values reveals that compounds 1b (0.0244 μM), 1e (0.0176 μM) and 1f (0.0125 μM) exhibit more affinity for the LCC than the other compounds. This screening shows that the two series of isoindolines
probably could act as LCC blockers. 相似文献
56.
Marian Pavelka Manuel Acosta Michal V. Marek Werner Kutsch Dalibor Janous 《Plant and Soil》2007,292(1-2):171-179
The parameter Q10 is commonly used to express the relationship between soil CO2 efflux and soil temperature. One advantage of this parameter is its application in a model expression of respiration losses
of different ecosystems. Correct specification of Q10 in these models is indispensable. Soil surface CO2 efflux and soil temperature at different depths were measured in a 21-year-old Norway spruce stand and a mountain grassland
site located at the Experimental Ecological Study Site Bily Kriz, Beskydy Mts. (NE Czech Republic), using automated gasometric
systems. A time-delay and goodness-of-fit between soil CO2 efflux and soil temperature at different measuring depths were determined. Wide ranges of values for the time-delay of CO2 efflux in response to temperature, Q10 and the determination coefficient (R2) between CO2 efflux and temperature were obtained at the both sites. The values of Q10 and the CO2 time-delay increased with depth, while the R2 of the CO2-temperature relationship significantly decreased. Soil temperature records obtained close to the soil surface showed the
highest values of R2 and the lowest value of the time-delay at both sites. Measurement of soil temperature at very shallow soil layer, preferably
at the soil surface, is highly recommended to determine useable values of Q10. We present a new procedure to normalize Q10 values for soil temperatures measured at different depths that would facilitate comparison of different sites. 相似文献
57.
New findings suggest that attention deficit and hyperactivity disorder (ADHD) is the most common behavioral variant associated with a mental condition. ADHD prevalence reaches figures of 18% in populations worldwide. Furthermore, genetic variants conferring susceptibility to develop ADHD are not rare but very frequent and eventually totally fixed in some populations. These patterns of evolution can be associated with the fact that this behavioral trait had provided selective advantage. However, this behavioral trait is now under scrutiny because of new emerging social necessities. Recent molecular and clinical evidence supports Thom Hartmann's Hunter-Farmer theory, reaffirming that ADHD might be an anachronic behavioral trait. 相似文献
58.
María Gabriela Cheluja Mariano Jos Scolari Trinidad María Coelho Mariano Guillermo Blake Mariano Martín Boccia Carlos María Baratti Gabriela Beatriz Acosta 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,146(4):499
Postnatal development changes in mechanisms of synaptosomal amino acid transport have been studied in rat cerebral cortex. Specific uptake of radiolabeled l-serine was examined and compared with that of radiolabeled GABA using synaptosomes-enriched fractions freshly prepared from cerebral cortex at different postnatal days from the birth to young adulthood. The preparations were incubated with 10 nM of [3H]l-serine and 10 nM of [3H]-GABA in either the presence or absence of NaCl, KCl or choline chloride, at 2 and 30 °C, for different periods up to 30 min. The uptake of [3H]l-serine was temperature dependent in synaptosomal fractions prepared from cerebral cortex of rats in postnatal days 5, 7, 13 and 21, but stronger dependence was observed in adult brain, irrespective of the presence of Na+, K+ or choline ions. At all postnatal ages studied, [3H]-GABA uptake showed a high activity in the presence of Na+ ions and at 30 °C. The values of Km were 90–489 μM in l-serine uptake. However, in the uptake of GABA the values of Km were 80–150 μM. The highest values of Vmax were obtained at 5 and 21 postnatal days for both transport systems. These results indicate that the uptake of l-serine and GABA are regulated differentially during postnatal development. 相似文献
59.
Crystal structure of a transcription regulator (TM1602) from Thermotoga maritima at 2.3 A resolution
Weekes D Miller MD Krishna SS McMullan D McPhillips TM Acosta C Canaves JM Elsliger MA Floyd R Grzechnik SK Jaroszewski L Klock HE Koesema E Kovarik JS Kreusch A Morse AT Quijano K Spraggon G van den Bedem H Wolf G Hodgson KO Wooley J Deacon AM Godzik A Lesley SA Wilson IA 《Proteins》2007,67(1):247-252
60.
María Lourdes Acosta Asterio Sánchez Francisco García Antonio Contreras Emilio Molina 《Cytotechnology》2007,54(3):189-200
Batch cultures were carried out to study the kinetic, stoichiometry, and regulation of glucose and glutamine metabolism of
a murine hybridoma line. Asymmetric logistic equations (ALEs) were used to fit total and viable cell density, and nutrient
and metabolite/product concentrations. Since these equations were analytically differentiable, specific rates and yield coefficients
were readily calculated. Asymmetric logistic equations described satisfactorily uncontrolled batch cultures, including death
phase. Specific growth rate showed a Monod-type dependence on initial glucose and glutamine concentrations. Yield coefficients
of cell and lactate from glucose, and cell and ammonium from glutamine were all found to change dramatically at low residual
glucose and glutamine concentrations. Under stoichiometric glucose limitation, the glucose-to-cell yield increased and glucose-to-lactate
yield decreased, indicating a metabolic shift. Under stoichiometric glutamine limitation the glutamine-to-cell and glutamine-to-ammonium
yields increased, but also glucose-to-cell yield increased and the glucose-to-lactate yield decreased. Monoclonal antibody
production was mainly non-growth associated, independently of glucose and glutamine levels. 相似文献