Evidence for a functional subdivision of Premotor Ear-Eye Field (Area 8B)

The Supplementary Eye Field (SEF) and the Frontal Eye Field (FEF) have been described as participating in gaze shift control. Recent evidence suggests, however, that other areas of the dorsomedial prefrontal cortex also influence gaze shift. Herein, we have investigated electrically evoked ear- and eye movements from the Premotor Ear-Eye Field, or PEEF (area 8B) of macaque monkeys. We stimulated PEEF during spontaneous condition (outside the task performance) and during the execution of a visual fixation task (VFT). In the first case, we functionally identified two regions within the PEEF: a core and a belt. In the core region, stimulation elicited forward ear movements; regarding the evoked eye movements, in some penetrations, stimulation elicited contraversive fixed-vectors with a mean amplitude of 5.14°; while in other penetrations, we observed prevalently contralateral goal-directed eye movements having end-points that fell within 15° in respect to the primary eye position. On the contrary, in the belt region, stimulation elicited backward ear movements; regarding the eye movements, in some penetrations stimulation elicited prevalently contralateral goal-directed eye movements having end-points that fell within 15° in respect to the primary eye position, while in the lateral edge of the investigated region, stimulation elicited contralateral goal-directed eye movements having end-points that fell beyond 15° in respect to the primary eye position. Stimulation during VFT either did not elicit eye movements or evoked saccades of only a few degrees. Finally, even though no head rotation movements were observed during the stimulation period, we viewed a relationship between the duration of stimulation and the neck forces exerted by the monkey's head. We propose an updated vision of the PEEF composed of two functional regions, core and belt, which may be involved in integrating auditory and visual information important to the programming of gaze orienting movements.

Stress exposure and postural control in young females

The aim of this study was to determine if heightened stress had an adverse affect on the postural control of 14 young right‑handed females during quiet standing in either the presence or the absence of visual input. The level of stress was evaluated by measuring the free cortisol response to awakening (cortisol awakening response; CAR) and by employing the perceived stress scale (PSS). Overall mood disturbance was measured using the profile of mood states (POMS). Postural control was evaluated using a force platform by measuring the 95% confidence ellipse area described by the center of pressure during 5 balance positions maintained for at least 52 sec, each with open and closed eyes. The results of this study revealed a significant positive correlation between CAR, PSS and POMS for each of the studied subjects. Furthermore, it was observed that whilst the level of stress was capable of influencing postural stability, this influence was particularly evident when no visual information was available. Additionally, it was determined that maintenance of posture is easier when the dominant foot is ahead, regardless of visual input.

Anthropometrics Related to the Performance of a Sample of Male Swimmers

The main purpose of the present investigation of 21 elite male swimmers was to assess whether the Ape Index (the ratio between the individual's arm span and height) and/or the second-to-fourth digit length ratio (2D:4D), i.e., the ratio between the length of the second and the fourth fingers of the right hand, are associated with the performance of high-level swimmers, when mood and / or executive function are covaried. The results showed no statistically significant correlation between the Ape Index and 2D:4D ratio, performance, executive function, or mood. In contrast, statistically significant correlations were found between 2D:4D ratio and performance, executive function, and mood. Regressions indicated that 2D:4D ratio and not Ape Index is related to the performances of a sample of male swimmers.

Attention and Blood Lactate Levels in Equestrians Performing Show Jumping

In equestrian show jumping, attention is particularly important to ensure maximum accuracy. Due to the anaerobic nature of the jumping and its requirement for precision coordination between human and horse, there may be a relation between the onset of lactic threshold and decrease in attention. In 12 healthy and injury-free equestrians (6 men, 6 women), the effects (blood lactate and glucose) of a show jumping course (250 m long with eight vertical obstacles with a height of 1.15 m height) on capacity and selectivity of attention was assessed. A typical reaction time paradigm and test of divided attention were administered. At the end of the course a significant increase of blood lactate was observed, whereas blood glucose did not significantly change. A deterioration of attention (intensity and selectivity) and a worsening of performance with increasing of blood lactate were observed. The present results led to the conclusion that the increase in blood lactate that occurs in riders executing a show jumping course is associated with worsening of both attentive capabilities and performance.

Consensus paper: current views on the role of cerebellar interpositus nucleus in movement control and emotion

In the present paper, we examine the role of the cerebellar interpositus nucleus (IN) in motor and non-motor domains. Recent findings are considered, and we share the following conclusions: IN as part of the olivo-cortico-nuclear microcircuit is involved in providing powerful timing signals important in coordinating limb movements; IN could participate in the timing and performance of ongoing conditioned responses rather than the generation and/or initiation of such responses; IN is involved in the control of reflexive and voluntary movements in a task- and effector system-dependent fashion, including hand movements and associated upper limb adjustments, for quick effective actions; IN develops internal models for dynamic interactions of the motor system with the external environment for anticipatory control of movement; and IN plays a significant role in the modulation of autonomic and emotional functions.

Changes in mood states and salivary cortisol levels following two months of training in elite female water polo players

Psychological and physiological markers have been used to maximize competitive sport preparation. The aim of the present study was to evaluate the effects of two months of training and competitions on mood states and salivary cortisol diurnal variation in 15 female elite water polo players. The results demonstrated that the β coefficient values of the regression slope of cortisol values on sampling time was significantly flatter following the training period. The values of the area under the cortisol curve (AUC) 'with respect to ground' (AUCg) and those of the β coefficients of the slope of the diurnal change in cortisol levels were highly negatively correlated. The slope correlated positively with the dysfunctional Profile of Mood States scale and negatively with the functional scale. AUCg correlated negatively with dysfunctional factors and positively with the vigor index. These findings support the hypothesis that subclinical hypocortisolism and a flattened diurnal rhythm of cortisol may play a role in determining dysfunctional mood states.

Recovery of damaged skeletal muscle in mdx mice through low-intensity endurance exercise

The lack of dystrophin in mdx mice leads to cycles of muscle degeneration and regeneration processes. Various strategies have been proposed in order to reduce the muscle-wasting component of muscular dystrophy, including implementation of an exercise programme. The aim of this study was to examine how low-intensity endurance exercise affects the degeneration-regeneration process in dystrophic muscle of male mdx mice. Mice were subjected to low-intensity endurance exercise by running on a motorized Rota-Rod for 5 days/week for 6 weeks. Histomorphological analysis showed a significant reduction of measured inflammatory-necrotic areas in both gastrocnemius and quadriceps muscle of exercised mdx mice as compared to matched sedentary mdx mice. The degenerative-regenerative process was also evaluated by examining the protein levels of connexin 39 (Cx39), a specific gene expressed in injured muscles. Cx39 was not detected in sedentary wild type mice, whereas it was found markedly increased in sedentary mdx mice, revealing active muscle degeneration-regeneration process. These Cx39 protein levels were significantly reduced in muscles of mdx mice exercised for 30 and 40 days, revealing together with histomorphological analysis a strong reduction of degeneration process in mice subjected to low-intensity endurance exercise. Muscles of exercised mdx mice did not show significant changes in force and fatigue resistance as compared to sedentary mdx mice. Overall in this study we found that specific low-intensity endurance exercise induces a beneficial effect probably by reducing the degeneration of dystrophic muscle.

Unique antineoplastic profile of Saquinavir-NO, a novel NO-derivative of the protease inhibitor Saquinavir, on the in vitro and in vivo tumor formation of A375 human melanoma cells

We have recently shown that covalent attachment of the nitric oxide (NO) moiety to the HIV protease inhibitor Saquinavir (Saq) produced a qualitatively new chemical entity, named Saquinavir-NO (Saq-NO), with enhanced anticancer properties and reduced toxicity both in vitro and in vivo. The aim of this study was to address several unanswered questions both on the pharmacological profile of Saq-NO as well as on the in vivo role of NO in the oncogenesis of A375 human melanoma cells. To this end, we have evaluated here the impact of single and combined effects of Saq-NO, Saq, the NO-donor DETA NONOate and the iNOS inhibitor L-NAME on the in vitro as well as in vivo growth of the iNOS positive A375 cells. Our data confirm clear-cut evidence for a strong and powerful anti-melanoma action of Saq-NO that is not duplicable by the combined use of Saq and DETA NONOate. Surprisingly, but also in agreement with the complex and multifaceted role of endogenous NO in A375 cells, both DETA NONOate and L-NAME significantly suppressed the in vivo growth of xenotransplants.

Creatine ingestion effects on oxidative stress in a steady-state test at 75% VO(2max)

AIM

The present study was carried out with the aim to analyze the role of creatine on oxidative stress during exercise, i.e. whether creatine is a pro-oxidative or an antioxidant substance.

METHODS

In a randomized double-blind study involving 30 adult males, we examined plasma lactate, oxidative stress markers (malondialdehyde, MDA) and glutathione redox ratio (GSSG·GSH-1), antioxidative systems (vitamins A, E, C), and ergospirometric responses (respiratory quotient and relative oxygen uptake) before and after 30 min steady-state tests 75% VO2max (placebo and creatine).

RESULTS

Ergospirometric tests, hematocrit values, blood lactate as well as vitamins A, E and C concentrations did not show significant differences between creatine and placebo testing. Conversely, oxidative stress markers MDA and GSSG·GSH-1 increased during placebo trials much more than in creatine trials.

CONCLUSION

This is the first report documenting that a creatine loading, i.e., a 0.3 g/kg/die of creatine ingestion for 5 consecutive days, could reduce the oxidative stress, whereas its consumption may not have a clear metabolic advantage in certain aerobic activities.

Therapeutic potential of carbon monoxide in multiple sclerosis

Carbon monoxide (CO) is produced during the catabolism of free haem, catalyzed by haem oxygenase (HO) enzymes, and its physiological roles include vasodilation, neurotransmission, inhibition of platelet aggregation and anti-proliferative effects on smooth muscle. In vivo preclinical studies have shown that exogenously administered quantities of CO may represent an effective treatment for conditions characterized by a dysregulated immune response. The carbon monoxide-releasing molecules (CORMs) represent a group of compounds capable of carrying and liberating controlled quantities of CO in the cellular systems. This review covers the physiological and anti-inflammatory properties of the HO/CO pathway in the central nervous system. It also discusses the effects of CORMs in preclinical models of inflammation. The accumulating data discussed herein support the possibility that CORMs may represent a novel class of drugs with disease-modifying properties in multiple sclerosis.

Physical and cognitive stimulation in Alzheimer Disease. the GAIA Project: a pilot study

Several data suggest that physical activity and cognitive stimulation have a positive effect on the quality of life (QoL) of people with Alzheimer's disease (AD), slowing the decline due to the disease. A pilot project was undertaken to assess the effect of cognitive stimulation, physical activity, and socialization on patients with AD and their informal caregiver's QoL and mood. Fourteen patients with AD were randomly divided into active treatment group and control group. At the end of treatment, a significant improvement in apathy, anxiety, depression, and QoL in the active treatment group was found. Considering caregivers, those of the active treatment group exhibited a significant improvement in their mood and in their perception of patients' QoL. This study provides evidence that a combined approach based on cognitive stimulation, physical activity, and socialization is a feasible tool to improve mood and QoL in patients with AD and their caregivers.

Neuronal activity reflecting progression of trials in the pre-supplementary motor area of macaque monkey: an expression of neuronal flexibility

We studied the activity of single neurons in the pre-supplementary motor area (pre-SMA) of macaque monkeys as they performed two visuomotor tasks, called the visual fixation task and the visual fixation-blink task. Both tasks involved a sequence of three visual stimuli, red followed by yellow and green. The tasks differed in that the latter one had a gap within the period of the red stimulus, called a "blink". The tasks were performed in two modes, one of which included movements of both the arm and eye and the other of which involved only eye movements. In the arm-eye mode, the monkeys had to press a bar and fixate the red stimulus that appeared after bar press. To receive a reward, both the bar press and visual fixation had to be maintained until the green stimulus triggered bar release. In the eye mode, bar press and bar release were eliminated from the task. Of the 42 neurons active during the visual fixation task, 15 showed task-related activity in both arm-eye and eye modes, and our analysis focused on these cells. We found that the introduction of the blink in visual fixation-blink task abolished the task-related activity of these cells over the course of 2-4 trials. This finding suggests a role for the pre-SMA in reflecting progression of trials as an updating of motor instruction.

The second-to-fourth digit ratio correlates with the rate of academic performance in medical school students

Prenatal androgens have important organizing effects on the development and future behavior of the brain. The second-to-fourth digit length ratio (2D:4D) has been proposed as a marker of these prenatal androgen effects, with a relatively longer fourth finger indicating higher prenatal androgen exposure. 2D:4D has been shown to predict the success of men who play sports and of financial traders. However, to date little is known regarding the effects of prenatal androgens on academic performance, for example, admission to and success in a highly competitive university system such as the state-run Italian medical schools. Here, we report the findings of a study conducted at the University of Catania Medical School, Italy, in which the 2D:4D ratio was sampled in a group of 48 male students. The 2D:4D ratios were found to be correlated with the performance of the students on the admission test to the medical school, their salivary testosterone levels and their aggressiveness; however, no correlation was observed with the mean score on exams during the course of study. Our results suggest that pre and/or postnatal androgens increase performance in situations that require prompt decision-making and the ability to take risks, but do not influence performance when a more analytical and planned approach is called for.

Neuronal NOS expression in rat's cuneate nuclei following passive forelimb movements and median nerve stimulation

Nitric oxide (NO) synthase (NOS) has been observed in the Cuneate Nuclei (CN), suggesting a role for NO in the modulation of their neurons' activity. The present study was undertaken to evaluate whether passive movement of forelimb as well as electric stimulation of medial nerve modulate the expression of neuronal isoform of NOS (nNOS) within CN. The experiments were carried out on 21 male Wistar rats, by using two different protocols. In the first group of rats the median nerve was stimulated with high frequency trains (phasic stimulation) or at constant frequency (tonic stimulation); as a control, in the third group, no stimulus was delivered. Moreover, in the second group of rats, we imposed to the animal's left forepaw circular paths at a roughly constant speed (continuous movement), or rapid flexions and extensions of the wrist (sudden movement); as a control, in the third group, no movement was imposed. After the experimental session, free-floating frontal sections of medulla oblongata were processed for nNOS or glutamate (GLU) immunohistochemistry. Phasic stimulation of the median nerve or sudden movements of the forelimb determines a significant decrement of the nNOS-positive neurons within the ipsilateral CN, whereas no effects were observed on GLU positive cells. We have also found a peculiar topographical distribution within IN of nNOS-positive neurons: positive cells were clustered at periphery of some "niches" having circular or elliptical form, with GLU positive cells at center.

Representation of movement velocity in the rat's interpositus nucleus during passive forelimb movements

The interpositus nucleus (IN) receives a large amount of sensory information from the limbs and, in turn, elaborates signals for movement control. In this paper, we tried to gather evidence on the possibility that neurons in the IN may elaborate sensory representations of the forelimb kinematics and, particularly, of the movement velocity vector. For this purpose, the forepaw of anesthetized rats was attached to a computer-controlled robot arm displaced passively along two types of trajectories (circular and figure eight), with the limb joints unconstrained. The firing activity of single cells was recorded and related to limb position and the two components of the movement velocity vector, namely, movement speed and direction. By using multiple regression analysis, we found that 12 out of 85 (14%) neurons were modulated by position, 18 out of 85 (21%) neurons were modulated by direction, 24 out of 85 (28%) neurons were modulated by movement speed, and 31 out of 85 (37%) neurons were sensitive to the full movement velocity vector. Most of the neurons modulated only by the speed component of the velocity vector (19 out of 24) were located in the posterior portion of the IN, whereas neurons in the anterior portion were mostly related to both components of the velocity vector. These results suggest that sensory information related to whole-limb movement velocity may be encoded by the IN, indicating also that the posterior interpositus may preferentially represent movement speed.

A galactose-free diet enriched in soy isoflavones and antioxidants results in delayed onset of symptoms of Krabbe disease in twitcher mice

Krabbe disease or globoid cell leukodystrophy is an autosomal recessively inherited disorder caused by the deficiency of galactocerebrosidase, the lysosomal enzyme that catalyzes the hydrolysis of galactose from galactosylceramide and galactosylsphingosine (psychosine). Psychosine accumulation results in the loss of myelin and oligodendrocytes in the brain of Krabbe patients as well as twitcher mice (natural model of human Krabbe disease). The aim of the present research was to investigate in twitcher mice the potential role of a diet deficient in galactose enriched in soy isoflavones and a pool of antioxidants molecules, such as l-glutathione, coenzyme Q10, xanthophylls, in counteracting the toxic effects derived by psychosine accumulation. A second goal of this manuscript was to demonstrate suppression of the apoptotic effects of psychosine in cultured oligodendrocyte progenitor mice cells (OLP-II) with antioxidants. The affected twitcher mice began the milk-derivatives free diet on post-natal day 15 although they also received mother's milk until post-natal day 18. Nevertheless, average life span was increased 50%, from 32+/-2 to 48+/-3 days, onset of tremor was delayed 17 days (from 21 days in the untreated twitcher mice to 38 days in the treated affected mice) and the gait in the treated mice was normal until almost a week after the untreated animals died (38+/-1 days versus 32 days at death). Weight gain in the treated animals also progressed to 38 days compared with 22 days for the untreated affected twitcher mice. Protection of the OLP-II cells against psychosine was shown using the MTT test (the ability of the tetrazolium salt MTT to form a dark blue formazan product by mitochondrial dehydrogenase in viable cells) and assay of expression of p53 and TNF-related apoptosis-inducing ligand (TRAIL). The results showed a time-dependent and concentration-dependent decrease of OLP-II viability on exposure to psychosine and dose-dependent protection with the antioxidants xanthophylls and glutathione. They also demonstrated that psychosine-induced p53 induction of apoptosis and TNF-related apoptosis-inducing ligand receptors could be decreased by l-glutathione and xanthophylls. A dietary approach may constitute a promising clinical management of the late-infantile and juvenile forms of Krabbe leukodystrophy.

Elevated blood lactate is associated with increased motor cortex excitability

No information has yet been provided about the influence of blood lactate levels on the excitability of the cerebral cortex, in particular, of the motor cortex. The aim of the present study was to examine the effects of high blood lactate levels, induced with a maximal cycling or with an intravenous infusion, on motor cortex excitability. The study was carried out on 17 male athletes; all the subjects performed a maximal cycling test on a mechanically braked cycloergometer, whereas 6 of them were submitted to the intravenous infusion of a lactate solution (3 mg/kg in 1 min). Before the exercise or the injection, at the end, as well as 5 and 10 min after the conclusion, venous blood lactate was measured and excitability of the motor cortex was evaluated by using the transcranial magnetic stimulation. In both of these experimental conditions, it was observed that an increase of blood lactate is associated with a decrease of motor threshold, that is, an enhancement of motor cortex excitability. We conclude by hypothesizing that in the motor cortex the lactate could have a protective role against fatigue.