Search results for "fisiologia"
showing 10 items of 672 documents
Temporal aspects of copper homeostasis and its crosstalk with hormones
2015
To cope with the dual nature of copper as being essential and toxic for cells, plants temporarily adapt the expression of copper homeostasis components to assure its delivery to cuproproteins while avoiding the interference of potential oxidative damage derived from both copper uptake and photosynthetic reactions during light hours. The circadian clock participates in the temporal organization of coordination of plant nutrition adapting metabolic responses to the daily oscillations. This timely control improves plant fitness and reproduction and holds biotechnological potential to drive increased crop yields. Hormonal pathways, including those of abscisic acid, gibberellins, ethylene, auxin…
Effects of physical activity on the lean and fat mass of the legs and on the femoral BMD in young adults
2010
Aim. To evaluate the effects of physical activity on the lean (LLM) and fat (FLM) mass of both legs and on the left femur neck bone mineral density (FemBMD) in young adults. Methods. Subjects were 48 healthy male, mean age 25 (range 20-32). Subjects were assigned to one of three groups according to the physical activity practiced from age 10 onwards: 17 sedentary subjects (A), 15 active subjects (B) and 16 athletes (C). LLM and FLM (g) were evaluated by Dual Energy X-ray Absorptiometry (DEXA), as well as FemBMD (g/cm2). The data is shown as mean values ± standard deviation. For the statistical analysis of the data, linear regression analysis and Student's t test for unpaired data were used.…
Role for NK1 and NK2 receptors in the motor activity in mouse colon
2007
The present study examined the effects induced by endogenous and exogenous activation of NK(1) and NK(2) receptors on the mechanical activity of mouse proximal colon. Experiments were performed in vitro recording the changes in intraluminal pressure from isolated colonic segments. Electrical field stimulation in the presence of atropine and guanethidine produced a small relaxation, followed by nonadrenergic noncholinergic (NANC) contraction. SR140333, NK(1) receptor antagonist, or SR48968, NK(2) receptor antagonist, significantly reduced the contraction, although SR48968 appeared more efficacious. The co-administration of SR140333 and SR48968 virtually abolished the NANC contraction. [Sar(9…
Evidence for the presence of functional protease activated receptor 4 (PAR4) in the rat colon
2004
Background and aims: Protease activated receptors (PARs) have been postulated to play a role during intestinal inflammation. The presence and role played by PAR4 in gastrointestinal functions have not been fully clarified. The aims of this study were: (i) to examine expression of PAR4 in rat proximal colon; (ii) to determine the mechanical effects induced by PAR4 activation in longitudinal muscle; and (iii) to characterise the underlying mechanisms. Methods: PAR4 expression was determined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. Mechanical activity was recorded as changes in isometric tension. Results: A PCR product corresponding to the predicted…
Effects of anxiety during mental arithmetic stress on heart rate variability in healthy subjects
2011
Aim: Anxiety may cause an increased risk of myocardial infarction by reductions in heart rate variability (HRV). However, no data exists on the effect of anxiety on a standard mental test of HRV. The aim of this study was to evaluate the association between anxiety elicited by mental stress and HRV. Methods: Effect of anxiety in the actual state (A-State) and in everyday life (A-Trait) has been assessed in 13 healthy subjects and its association to low (LF) and high-frequency (HF) of HRV during mental arithmetic stress has been tested through correlation analysis. Results: A significant increase from baseline through arithmetic stress was observed in the LF component (LF(nu) from 56.87 ± 4.…
Application of T-pattern analysis in the study of the organization of behavior
2020
Application of multivariate t-pattern analysis in the study of social interactions in rats
2013
A basic tenet in the realm of modern behavioral sciences is that behavior consists of patterns in time. For this reason, investigations of behavior deal with sequences that are not easily perceivable by the unaided observer. This problem calls for improved means of detection, data handling and analysis. This review focuses on the analysis of the temporal structure of behavior carried out by means of a multivariate approach known as T-pattern analysis. Using this technique, recurring sequences of behavioral events, usually hard to detect, can be unveiled and carefully described. T-pattern analysis has been successfully applied in the study of various aspects of human or animal behavior such …
T-Patterns in the study of movement disorders
2019
An intrinsic feature of behaviour orbits around its temporal dimension consisting of patterns in time: investigations on behaviour necessarily deal with sequences often impossible to be perceived by the human eye [Eibl-Eibesfeldt I. Ethology: the biology of behavior. New York: Holt, Rinehart and Winston. 1970]. Thus, the study of behavioural sequencing in terms of higher order arrangements, how the sequences are structured and, importantly, their analysis in normal subjects and in subjects affected by specific movement/behavioural disorders may represent a stimulating but challenging task. By means of T-Pattern analysis (TPA), it is possible to study these hidden features of behaviour and, …
Recurring sequences of multimodal non-verbal and verbal communication during a human psycho-social stress test: A temporal pattern analysis
2020
Abstract Background The Trier Social Stress Test (TSST) is a widely used protocol to study human psycho-social stress responses. Quantitative reports of non-verbal behaviors have been carried out by means of the Ethological Coding System for Interviews (ECSI). However, no data have described whether and how non-verbal and verbal behaviors take part in the composition of multimodal sequences of communication during the test. Method Five non-verbal ECSI categories and four verbal behaviors related with communication were included in the Ethogram. A focal sampling was employed to ensure a high temporal resolution of the behavioral annotation. T-Pattern Analysis was employed to detect statistic…