1,721,582 research outputs found
Terpenoid profiles of resin in the genus Dracaena are species specific
No full textVaníčková, Lucie, Pompeiano, Antonio, Maděra, Petr, Massad, Tara Joy, Vahalík, Petr (2020): Terpenoid profiles of resin in the genus Dracaena are species specific. Phytochemistry (112197) 170: 1-8, DOI: 10.1016/j.phytochem.2019.112197, URL: http://dx.doi.org/10.1016/j.phytochem.2019.11219
Response characteristics of different size vestibulospinal neurons to roll tilt of the animal and neck rotation in decerebrate cat with the cerebellum intact
No full textEffects of sleep deprivation on the post-natal development of visual deprived cells in the cat's lateral geniculate nucleus
No full textFos-related antigens (FRAs) are involved in the transcriptional responses of locus coeruleus (LC) neurons to altered gravitational fields in rats
No full textLocus coeruleus (LC) neurons, which have widespread projections to the whole brain, respond to natural stimulation of macular receptors. Using immunocytochemistry we investigated whether rats exposed to altered gravitational fields showed changes in Fos and Fos-related antigen (FRA) protein levels in the LC. Fos protein is induced very rapidly and returns to basal levels within hours after stimulation, while FRAs persist for days or weeks after induction. Adult male albino rats (Fisher 344) were sacrificed at different time points during a space flight (NASA Neurolab Mission, STS-90) and the numbers of Fos- and FRA-positive cells in the LC were counted and compared to those in ground-based control rats. No significant changes in Fos protein expression were detected in the LC under different space flight conditions. In contrast, the number of FRA-positive cells increased on average to 167% of that of the controls at FD2, i.e. when gravity increased from 1 to 3 g during the launch before reaching about 0 g. FRA-labeled neurons then decreased to 46% of control values at FD14, i.e. after adaptation to 0 g, but increased again to 317% of control values at R + 1, when the animals were exposed to an increase in gravitational force from 0 to 1.5-1.8 g before reaching 1 g during landing. The number of labeled cells was 193% of the control values at R + 13, i.e. after readaptation to 1 g. Thus gravitational force appears to be very effective in inducing a long-term increase in FRA protein expression in the LC. Because activity in the noradrenergic LC neurons may increase Fos expression in several target structures, we postulate that the long-lasting induction of FRAs in the LC at FD2, and more prominently at R + 1, may contribute to the long-term molecular changes which probably occur in the brain during adaptation to 0 g and readaptation to 1 g
Il chiosco pompeiano a Chiavari
No full textConfronto tra vari metodi di rilievo ed analisi critica delle varie metodologie utilizzate, dal rilievo diretto di tipo tradizionale al rilievo strumentale (topografico, laser scanner e fotogrammetria digitale, di una piccola costruzione, il Chiosco pompeiano appunto, sito nel parco di villa Rocca a Chiavari
Gene expression in autonomic areas of the medulla and the central nucleus of the amygdala in rats during and after space flight
No full textDuring space flight astronauts show vestibular- related changes in balance, eye movements, and spontaneous and reflex control of cardiovascular, respiratory and gastrointestinal function, sometimes associated with space motion sickness. These symptoms undergo compensation over time. Here we used changes in the expression of two immediate-early gene (IEG) products to identify cellular and molecular changes occurring in autonomic brainstem regions of adult male albino rats killed at different times during the Neurolab Space Mission (STS-90). Both direct effects of gravitational changes, as well as indirect effects of gravitational changes on responses to light exposure were examined. Regions under the direct control of vestibular afferents such as the area postrema and the caudal part of the nucleus of the tractus solitarius (NTSC) were both directly and indirectly affected by gravity changes. These areas showed no changes in the expression of IEG products during exposure to microgravity with respect to ground controls, but did show a significant increase 24 h after return to 1 G (gravity). Exposure to microgravity significantly inhibited gene responses to light exposure seen after return to 1 G. A similar direct and indirect response pattern was also shown by the central nucleus of the amygdala, a basal forebrain structure anatomically and functionally related to the NTS. The rostral part of the NTS (NTSR) receives different afferent projections than the NTSC. This region did not show any direct gravity-related changes in IEG expression, but showed an indirect effect of gravity on IEG responses to light. A similar pattern was also obtained in the intermediate reticular nucleus and the parvocellular reticular nucleus. Two other medullary reticular structures, the dorsal and the ventral medullary reticular nuclei showed a less well defined pattern of responses that differed from those seen in the NTSC and NTSR. The short- and long-lasting molecular changes in medullary and basal forebrain gene expression described here are thought to play an important role in the integration of autonomic and vestibular signals that ultimately regulate neural adaptations to space flight. (C) 2004 IBRO. Published by Elsevier Ltd. All rights reserved
Il gran musaico Pompeiano : spiegato critiche osservazioni su quanto /
No full textMode of access: Internet.Sloan candidat
Immediate-early gene (IEG) expression during sleep (S) and waking (W) in prolonged continuous illumination (LL)
No full textImmediate-early gene (IEG) expression in inferior olive (IO) and other precerebellar structures in rats exposed to altered gravitational fields (NASA Neurolab Mission)
No full textShort-term (Fos) and long-term (FRA) protein expression in rat locus coeruleus neurons during the Neurolab mission: contribution of altered gravitational fields, stress, and other factors
No full textChanges in immediate-early gene (IEG) expression during and after space flight were studied in the rat locus coeruleus (LC) during the NASA Neurolab mission. The LC sends widespread projections throughout the brain and releases the neuromodulator norepinephrine. LC neurons respond to natural vestibular stimulation; their firing rate also increases during waking and decreases or ceases during sleep. LC neurons express IEGs such as c-fos after activation. Adult male albino Fisher 344 rats were killed at four mission time points, and the number of Fos- and Fos-related antigen (FRA)-positive LC cells were counted in flight and ground-based control rats. Half of the subjects at each time point were exposed to light for 60 min prior to killing to standardize their sleep-waking state. FRA-expressing cells were more numerous than Fos-expressing cells in both flight- and ground-based subjects. The difference between FRA- and Fos-expressing cells within individuals was significantly larger 24 h after landing in subjects exposed to both space flight and light pulse than in all other subjects at any mission time point. Fos and FRA responses scaled in proportion to the maximum response observed in any single individual showed similar patterns of variation. Analysis of the scaled and combined responses showed that LC IEG levels responded to both gravity changes and light pulses. Subjects exposed to either single stimulus had equivalent responses, significantly greater than those of control subjects maintained in dim light. The combination of gravity change and light pulse gave significantly higher LC responses than either stimulus alone 24 h after takeoff, and to a lesser extent after 12 days in space; the highest responses were obtained 24 h after landing. By 14 days after landing, animals exposed to space flight and light pulse responded no differently than ground-based subjects. No difference in LC IEG expression was clearly attributable to changes in the sleep-waking state of subjects. Activity of noradrenergic LC neurons has been previously shown to modulate IEG expression in target structures. The increased IEG LC activity (seen most especially 24 h after landing) may reflect large-scale activation of noradrenergic neurons that may serve as a trigger for molecular changes in target structures, and be critical for adaptation to gravity changes. (C) 2002 IBRO. Published by Elsevier Science Ltd. All rights reserved
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