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The use of oral appliances is considered effective in improving sport performance. Jaw clenching or stretching, improved breathing or positioning of the jaw have been proposed to explain the improvement. In this study, we reported the effects of regularly practiced mandibular stretching at submaximal opening of the jaw in Crossfit athletes. Seventeen test subjects undergoing mandibular stretching (MS) showed significantly reduced (p0.001) performance time in a high-intensity workout measured before and after seven days of 10-minutes stretching practiced twice daily, while no improvement was observed in control subjects who did not perform the stretching. Additionally, blood lactate levels appeared to recover more quickly in MS subjects.Crossfit is a type of training regimen that pushes the limits of bodily recovery processes. Jaw stretching, eliciting the trigeminocardiac reflex (a reflex decrease in heart rate and blood pressure following trigeminal stimulation) and central oxygen-conserving mechanisms could help relieve post-training stress and improve training recovery.

The existence of a learning effect by which subjects progressively reduce body sway over the course of repetitive stabilometric measurements is currently debated. Also, the position and orientation of the feet on the platform can have a substantial influence on the outcome measurements. The aim of the present work was to assess the effect of feet positions on mean total velocity (V) of the center of pressure and the area (AR) covered by its displacements during quiet standing. A group of 35 healthy young subjects was examined during two successive sessions consisting of five recordings with their feet placed either in the recommended (standard, SP) or their usual most comfortable (UP) position. Results show a slight decreasing trend that failed to be statistically significant checked with Friedman's ANOVA (SP AR, χ2(4)=6.10, p=0.19 and V, χ2(4)=8.66, p=0.07 and UP AR, χ2(4)=2.32, p=0.68 and V, χ2(4)=1.19, p=0.88). Nonetheless, values of AR and V showed a notable decrement especially evident in the SP exam reaching, respectively, 24% and 11% from baseline, whereas variability measured by the coefficient of variation was the same in the two exams. Given the results, a learning effect should not be ruled out with confidence. Also, usual foot placement would be preferable to avoid this effect. Further research is needed to take into consideration the great variability of stabilometric measurements and the fact that different subjects could adapt more readily to the test conditions than others.

Contextual fear conditioning (CFC) paradigm is routinely used to study fear-based learning in animals and it provides a useful model for understanding fear and anxiety in human. In the present study, such model was used following the previously established CFC protocol, and immunohistochemistry, enzymatic activity and western blotting analysis approaches were used to identify the expression of acid sphingomyelinase (aSMase) and vitamin D receptor (VDR) in prefrontal region brain of rat. Results revealed an increase of aSMase activity in conditioned rats, suggesting an apoptotic condition in such animals. In addition, an increase of density and organization of axonal neurofilaments and of VDR expression has been observed in brain of conditioned rats, supporting an induction of growth and organization of new neurons in prefrontal regions, whose contribution to various aspects of contextual fear learning is still largely unknown.

In recent years people suffering of backache has significantly increased. This led us to focus our attention on the adequacy of school furniture for the correct development of the adult posture. The standing posture of 67 students of middle school has been analyzed at the beginning and at the end of two consecutive scholastic years using a stabilometric platform. Starting from the second year, about half of the students were provided with the furniture designed following European standard (UNI EN 1729:2006), while the other half maintained the traditional one. The main purpose of this research has been to verify by means of posturometric analysis the effects on postural parameters of the use of traditional furniture in comparison to the furniture following the UNI EN 1729:2006. We observed that prolonged sitting at school changes some posturometric variables of schoolchildren. Since no differences has been found between the two groups, the validity of the European standards is questioned. The present study allowed us to single out four anthropometric parameters that should be considered in order to devise a new model of adjustable furniture. By adjusting every year the furniture of each student, it would be possible to avoid (at least at school) the adoption of wrong postural positions that could be responsible for backache and other common musculoskeletal disorders.

Contextual fear conditioning (CFC) is a quick cognitive test based on the association context-aversive stimulus in which a single training leads to a long-term memory. Previously, we showed that 2 days after conditioning the expression of the genes Napa, Pnf2, Casp3, Pdrg1, Ywhaz, Stmn1, Bpgm, were positively modulated in CFC rats respect to naïve rats, explor rats which had freely explored the experimental apparatus and SO rats to which the same number of aversive shocks used in CFC paradigm had been administered in the same CFC apparatus in less time to prevent the association between painful stimuli and apparatus, whereas the genes Actr3, Pea15 and Tiprl were more expressed in SO rats and Cplx1, Trim32 and Ran genes were more expressed in explor rats. At 2 days, Tomm20 gene expression resulted positively modulated in both CFC and explor rats. Herein, we have tested the expression of these genes for a period longer than 2 days, by monitoring the modulation of transcripts within 20 days after conditioning. The expression of the transcripts was assessed by qRT-PCR.We found that three days after CFC only the genes Tiprl and Trim32 were positively modulated in CFC rats whereas the gene Tomm20 was negatively modulated in CFC rats as well as in SO and explor rats. Ten days after CFC, the expression of Trim32 was still positively modulated whereas the genes Tiprl and Tomm20 returned to the constitutive level, and the gene Ran was significantly more expressed in CFC rats than in naïve, SO and explor rats. Interestingly, 20 days after CFC, the genes Stmn1 and Tiprl again became significantly more expressed in CFC rats compared with naïve, SO and explor rats.

In the present study the ribosomal RNA of the leech Hirudo medicinalis has been characterized at the aim of identifying possible analogies with other invertebrates. Upon electrophoresis on denaturating gels, ribosomal RNA fraction of H. medicinalis exhibited a remarkable thermal instability by dissociating into two hydrogen-bonded components when heated at 60 degrees C, at variance with the behaviour of the rat rRNA, which does not show this process. This result suggests a functional role in leech ribosome organisation that requires deeper structural studies.

Over the past six years, Ca2+ channels have continued to receive much attention, partly as a result of their biological importance as excitation-response transducers, and partly as a result of exciting developments in enlightening their molecular properties and cellular functions. Neurotransmitter release, neurosecretion, neuronal excitation, survival of neurons, and many other neuronal functions are controlled by the cellular [Ca2+]. In turn the rise in [Ca2+]i modulates specific cellular functions. The enhancement of [Ca2+]i is modulated by various factors, peptidergic and not.