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Different Time Courses (different + time_course)
Selected AbstractsTime course of EEG background activity level before spontaneous awakening in infantsJOURNAL OF SLEEP RESEARCH, Issue 4 2002Chiara Zampi SUMMARY This research aimed to investigate the time course of the cortical activity level preceding spontaneous awakening as a function of age and state. Two groups of infants (1,4 and 9,14 weeks of age) were continuously monitored by polygraphic recording and behavioural observation during the night. The electroencephalographic (EEG) activity recorded by the C3,O1 lead was analysed through an automatic analysis method which provides, for each 30-s epoch, a single measure, time domain based, of the EEG synchronization. The EEG parameter values were computed in the 6 min preceding each awakening out of non-rapid eye movement (NREM) sleep and out of rapid eye movement (REM) sleep. The EEG background activity level did not change in the minutes preceding awakening out of REM sleep. Awakening out of NREM sleep was preceded by a change of EEG activity level in the direction of higher activation with different time course according to the age. Both REM and NREM sleep results suggest that a high level of EEG activity is a prerequisite for the occurrence of a spontaneous awakening. [source] Fluorescein leakage of the optic disc: time course in primary open-angle glaucomaOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2010Niklas Plange Abstract Purpose:, To identify and quantify the time course of fluorescein leakage of the optic nerve head in primary open-angle glaucoma (POAG) and controls. Methods:, Twenty patients with POAG (aged 58 ± 10 years) and 14 controls (aged 51 ± 12 years, p = 0.07) were included in a prospective study. Fluorescein leakage of the optic disc was quantified using digital image analysis. A new leakage ratio (fluorescence of the optic disc divided by fluorescence of the surrounding retina) was defined and fluorescein leakage was quantified at 7,8, 9,10, 11,12, and 13,14 min after injection of 2.5 cc sodium fluorescein (10%). Results:, The fluorescein leakage exhibited a significantly different time course with higher leakage ratio values in POAG compared to controls (7,8 min: 1.24 ± 0.32 vs 1.16 ± 0.12; 9,10 min: 1.37 ± 0.37 vs 1.19 ± 0.1; 11,12 min: 1.38 ± 0.36 vs 1.24 ± 0.13; 13,14 min: 1.44 ± 0.36 vs 1.27 ± 0.13; p = 0.004). The change in optic disc fluorescence from 7,8 min to 9,10 min was significantly higher in POAG compared to controls (0.13 ± 0.09 vs 0.03 ± 0.07; p = 0.002). Conclusion:, The time course of fluorescein leakage is significantly different in POAG compared to controls. This might reflect damage of the optic disc vasculature related to increased vascular permeability. [source] Greater growth hormone and insulin response in women than in men during repeated bouts of sprint exerciseACTA PHYSIOLOGICA, Issue 2 2009M. Esbjörnsson Abstract Aim:, In a previous study, sprint training has been shown to increase muscle cross-sectional area in women but not in men [Eur J Appl Physiol Occup Physiol 74 (1996) 375]. We hypothesized that sprint exercise induces a different hormonal response in women than in men. Such a difference may contribute to explaining the observed gender difference in training response. Method:, Metabolic and hormonal response to three 30-s sprints with 20-min rest between the sprints was studied in 18 physically active men and women. Results:, Accumulation of blood lactate [interaction term gender (g) × time (t): P = 0.022], and plasma ammonia (g × t: P < 0.001) after sprint exercise was greater in men. Serum insulin increased after sprint exercise more so in women than in men (g × t: P = 0.020), while plasma glucose increased in men, but not in women (g × t: P < 0.001). Serum growth hormone (GH) increased in both women and men reaching similar peak levels, but with different time courses. In women the peak serum GH level was observed after sprint 1, whereas in men the peak was observed after sprint 3 (g × t; P < 0.001). Serum testosterone tended to decrease in men and increase in women (g × t: P = 0.065). Serum cortisol increased approx. 10,15% after sprint exercise, independent of gender (time: P = 0.005). Conclusion:, Women elicited a greater response of serum GH and insulin to sprint exercise. This may contribute to explaining the earlier observed muscle hypertrophy in women in response to sprint training. [source] Deletion of tau attenuates heat shock-induced injury in cultured cortical neuronsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2010Yanying Miao Abstract The microtubule-associated protein tau has been implicated in ,-amyloid- and glutamate-induced neurotoxicity. However, the potential role of tau in response to other insults to neurons remains unclear. In this study, we examined whether deletion of tau would change cell injury induced by heat shock in primary cultures of cortical neurons. After 30 min of a 45°C heat shock, lactate dehydrogenase (LDH) release increased, reaching a peak at 6 hr in wild-type (WT) neurons. A significantly lower LDH release, with a peak delayed by 24 hr, was detected in tau knockout (TKO) neurons. After heat shock treatment, MAP-2 and tubulin staining of the processes of WT neurons revealed more dramatic abnormalities than in TKO neurons. Both WT and TKO neurons exhibited a similar elevation of HSP70 level but different time courses of Akt phosphorylation. In contrast to an early, brief response in WT neurons, TKO neurons displayed a late, but long-lasting increase in phosphorylation of Akt and its downstream target, glycogen synthase kinase 3,. Additionally, inhibition of Akt activity aggravated the cell morbidity caused by heat shock exposure in both WT and TKO neurons, indicating a protective role of Akt against cell injury. In conclusion, our results demonstrate that deletion of tau attenuated heat shock-induced neuronal injury. Enhanced Akt response in the absence of endogenous tau is suggested to represent a compensatory mechanism for regulating cell reactions to stress stimuli. © 2009 Wiley-Liss, Inc. [source] Diurnal variations in the waking EEG: comparisons with sleep latencies and subjective alertnessJOURNAL OF SLEEP RESEARCH, Issue 3 2000Lafrance Daytime measures of sleep latency and subjective alertness do not correlate with one another, suggesting that they assess different aspects of alertness. In addition, their typical diurnal variations show very different time courses. Quantitative analysis of the waking electroencephalogram (EEG) has been proposed as an objective measure of alertness, but it is not clear how it compares with other measures. In this study, the waking EEG was measured in the daytime to determine the presence of diurnal variations in the activity of standard frequency bands and to compare these variations with the temporal patterns typical of sleep propensity and subjective alertness. Alertness was evaluated in four men and 12 women, aged 19,33 y. Assessments were conducted every 2 h, from 10.00 to 24.00, in the following order: a visual analogue scale of alertness, a waking EEG recording and a sleep latency test. The waking EEG was recorded with eyes open. For each recording session, 32,60 s of artefact-free signals were selected from the C3/A2 derivation, then subjected to amplitude spectral analysis. Four EEG frequency bands showed significant diurnal variations: delta, theta, sigma and beta1. None of these variations showed a significant correlation with the temporal patterns of sleep latencies or subjective alertness. At the individual level, however, theta band activity increased when subjective alertness decreased, suggesting that the theta band can be used to monitor variations in alertness in a given individual, even at the moderate levels of sleepiness experienced during the daytime. [source] Time course of vocal modulation during isolation in common marmosets (Callithrix jacchus)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 8 2010Chieko Yamaguchi Abstract Common marmosets vocalize phee calls as isolation calls, which seem to facilitate their reunion with family groups. To identify multiple acoustic properties with different time courses, we examined acoustic modulations of phees during different social contexts of isolation. Subject marmosets were totally isolated in one condition, were visually isolated and could exchange vocalizations in another condition, and were visually isolated and subsequently totally isolated in a third condition. We recorded 6,035 phees of 10 male,female marmoset pairs and conducted acoustic analysis. The marmosets frequently vocalized phees that were temporally elongated and louder during isolation, with varying time courses of these changes in acoustic parameters. The vocal rates and sound levels of the phees increased as soon as the marmosets saw their pair mates being taken away, and then gradually calmed down. The phee duration was longer in conditions during which there were no vocal responses from their pair mates. Louder vocalizations are conspicuous and seem to be effective for long-distance transmission, whereas shorter call duration during vocal exchanges might avoid possible vocal overlap between mates. Am. J. Primatol. 72:681,688, 2010. © 2010 Wiley-Liss, Inc. [source] Combined analysis of intracellular signalling and immunophenotype of human peripheral blood basophils by flow cytometry: a proof of conceptCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2007D. G. Ebo Summary Background The signal transduction pathways and control mechanisms involved in IgE-mediated basophil activation remain incompletely understood. Objectives To investigate whether basophilic intracellular signal transduction and immunophenotype can be analysed simultaneously by flow cytometry. Methods Basophils in whole blood were stimulated with anti-IgE and latex antigen at various concentrations and during different time courses. Phosphorylation of p38 mitogen-activated protein kinase (MAPK) as a representative of the intracellular signal transduction pathway and surface expression of CD63 was assessed simultaneously flow cytometrically. The effect of pre-incubation with IL-3 was assessed. Results Stimulation of the basophils with anti-IgE and allergen induces a rapid phosphorylation of p38 MAPK that peaks between 1 and 5 min and returns to baseline levels after 60 min. In contrast, CD63 up-regulation demonstrates a maximal but more continuous expression that peaks approximately 5 min later than phosphorylation of p38 MAPK. Specific inhibition of p38 MAPK reduced or almost completely abrogated up-regulation of CD63. Pre-incubation of the basophils with IL-3 produces a rapid p38 MAPK phosphorylation over basal levels, but this was weaker and shorter than for anti-IgE stimulation. Pre-incubation of the basophils with IL-3 did not potentiate anti-IgE-induced phosphorylation of p38 MAPK and did affect spontaneous or IgE-mediated CD63 up-regulation. Conclusions This study provides the proof that the flow cytometer allows an integrated analysis of basophilic intracellular signalling and immunophenotyping. Owing to its technical simplicity, the low number of cells required and rapid analysis, the technique seems promising for use in the clinic as a diagnostic tool or to monitor therapy. Capsule summary This study is the first to provide evidence for a combined analysis of basophilic intracellular signalling and immunophenotyping by flow cytometry. Owing to its technical simplicity, the low number of cells required and rapid analysis, the technique seems promising for use in the clinic as a diagnostic tool or to monitor therapy. [source] | |||||||||||||