Évaluation de la Pensée Constructive chez les adolescents délinquants: une approche pour comprendre les réponses inadaptées au stress

Objective: This pilot study aims at assessing Constructive Thinking in a sample of adolescent offenders and in a normative sample of adolescents. Method: 66 adolescent offenders (12-18 years) were compared to 540 control adolescents on the different subscales of the "Constructive Thinking Inventory". Results and Conclusion: Adolescent offenders show a less efficient Constructive Thinking: they show cognitive styles that may hamper their ability to take appropriate decisions when facing stressful situations, increasing self-defeating behaviors. Interventions may focus on improving adequate coping with stress.

Dicarboxylic amino acids and glycine-betaine regulate chaperone-mediated protein-disaggregation under stress.

Active protein-disaggregation by a chaperone network composed of ClpB and DnaK + DnaJ + GrpE is essential for the recovery of stress-induced protein aggregates in vitro and in Escherichia coli cells. K-glutamate and glycine-betaine (betaine) naturally accumulate in salt-stressed cells. In addition to providing thermo-protection to native proteins, we found that these osmolytes can strongly and specifically activate ClpB, resulting in an increased efficiency of chaperone-mediated protein disaggregation. Moreover, factors that inhibited the chaperone network by impairing the stability of the ClpB oligomer, such as natural polyamines, dilution, or high salt, were efficiently counteracted by K-glutamate or betaine. The combined protective, counter-negative and net activatory effects of K-glutamate and betaine, allowed protein disaggregation and refolding under heat-shock temperatures that otherwise cause protein aggregation in vitro and in the cell. Mesophilic organisms may thus benefit from a thermotolerant osmolyte-activated chaperone mechanism that can actively rescue protein aggregates, correctly refold and maintain them in a native state under heat-shock conditions.

Reinitialization of evolutionary clocks during sublethal environmental stress in some invertebrates

This paper describes the influence of high environmental stress on evolutionary trends in some selected Mesozoic ammonite lineages and some protists. During extinction periods, many ammonoids are affected by drastic simplifications of their shell geometry, ornamentation and suture line. We observe that relatively tightly coiled ammonites can give rise to highly evolute forms or uncoiled heteromorphs with simple ornamentation and almost ceratitic suture line-a phenomenon called "proteromorphosis". Such simplifications often correspond to a reappearance of ancestral geometries (primitive ornamentation, evolute coiling or uncoiling) which suggest that the evolutionary clock of these organisms can be reinitialized by extreme, sublethal, environmental stress such as giant volcanism (including its consequences on diverse pollutions and on climatic changes) and major regressive events. (c) 2006 Elsevier B.V. All rights reserved.

Combining heat stress and moderate hypoxia reduces cycling time to exhaustion without modifying neuromuscular fatigue characteristics.

PURPOSE: This study investigated the isolated and combined effects of heat [temperate (22 °C/30 % rH) vs. hot (35 °C/40 % rH)] and hypoxia [sea level (FiO2 0.21) vs. moderate altitude (FiO2 0.15)] on exercise capacity and neuromuscular fatigue characteristics. METHODS: Eleven physically active subjects cycled to exhaustion at constant workload (66 % of the power output associated with their maximal oxygen uptake in temperate conditions) in four different environmental conditions [temperate/sea level (control), hot/sea level (hot), temperate/moderate altitude (hypoxia) and hot/moderate altitude (hot + hypoxia)]. Torque and electromyography (EMG) responses following electrical stimulation of the tibial nerve (plantar-flexion; soleus) were recorded before and 5 min after exercise. RESULTS: Time to exhaustion was reduced (P < 0.05) in hot (-35 ± 15 %) or hypoxia (-36 ± 14 %) compared to control (61 ± 28 min), while hot + hypoxia (-51 ± 20 %) further compromised exercise capacity (P < 0.05). However, the effect of temperature or altitude on end-exercise core temperature (P = 0.089 and P = 0.070, respectively) and rating of perceived exertion (P > 0.05) did not reach significance. Maximal voluntary contraction torque, voluntary activation (twitch interpolation) and peak twitch torque decreased from pre- to post-exercise (-9 ± 1, -4 ± 1 and -6 ± 1 % all trials compounded, respectively; P < 0.05), with no effect of the temperature or altitude. M-wave amplitude and root mean square activity were reduced (P < 0.05) in hot compared to temperate conditions, while normalized maximal EMG activity did not change. Altitude had no effect on any measured parameters. CONCLUSION: Moderate hypoxia in combination with heat stress reduces cycling time to exhaustion without modifying neuromuscular fatigue characteristics. Impaired oxygen delivery or increased cardiovascular strain, increasing relative exercise intensity, may have also contributed to earlier exercise cessation.

Impact of physical activity on energy balance, food intake and choice in normal weight and obese children in the setting of acute social stress: a randomized controlled trial.

BACKGROUND: Psychological stress negatively influences food intake and food choices, thereby contributing to the development of childhood obesity. Physical activity can also moderate eating behavior and influence calorie intake. However, it is unknown if acute physical activity influences food intake and overall energy balance after acute stress exposure in children. We therefore investigated the impact of acute physical activity on overall energy balance (food intake minus energy expenditure), food intake, and choice in the setting of acute social stress in normal weight (NW) and overweight/obese (OW/OB) children as well as the impact of psychological risk factors. METHOD: After receiving written consent from their parents, 26 NW (BMI < 90(th) percentile) and 24 7-to 11-year-old OW (n = 5)/OB (n = 19, BMI ≥ 90(th) percentile) children were randomly allocated using computer-generated numbers (1:1, after stratification for weight status) to acute moderate physical or to sedentary activity for 30 min. Afterwards, all children were exposed to an acute social stressor. Children and their parents completed self-report questionnaires. At the end of the stressor, children were allowed to eat freely from a range of 12 different foods (6 sweet/6 salty; each of low/high caloric density). Energy balance, food intake/choice and obesity-related psychological risk factors were assessed. RESULTS: Lower overall energy balance (p = 0.019) and a decreased choice of low density salty foods (p < 0.001) in NW children compared with OW/OB children was found after acute moderate physical activity but not sedentary activity. Independent of their allocation, OW/OB children ate more high density salty foods (104 kcal (34 to 173), p = 0.004) following stress. They scored higher on impulsive behavior (p = 0.005), restrained eating (p < 0.001) and parental corporal punishment (p = 0.03), but these psychological factors were not related to stress-induced food intake/choice. Positive parenting tended to be related to lower intake of sweet high density food (-132 kcal, -277 to 2, p = 0.054). CONCLUSIONS: In the setting of stress, acute moderate physical activity can address energy balance in children, a benefit which is especially pronounced in the OW/OB. Positive parenting may act as a protective factor preventing stress-induced eating of comfort food. TRIAL REGISTRATION: clinicaltrials.gov NCT01693926 The study was a pilot study of a project funded by the Swiss National Science Foundation (CRSII3_147673).

Non-traumatic spinal cord ischaemia in childhood - clinical manifestation, neuroimaging and outcome.

BACKGROUND: Spinal cord ischaemia is rare in childhood and information on clinical presentation and outcome is scarce. METHODS: This is a retrospective analysis of eight patients and 75 additional cases from the literature. Data search included: patient's age, primary manifestation, risk factors, neuroimaging and outcome. RESULTS: Five female and three male patients gave consent to participate. Mean age was 12.5 years (10-15 years). Six patients presented with paraplegia; this was preceded by pain in four. Brown Sequard syndrome and quadriparesis were the two others' presenting condition. Sensation levels were thoracolumbar in seven cases. Bladder dysfunction only or bladder and bowel dysfunction were reported in eight and five patients respectively. Time to maximal symptom manifestation was <12 h in 7/8. Risk factors included surgery, minor trauma, recent infection, and thrombophilia. Mean follow-up was 3.3 years (0.25-6.3 years). Three patients remained wheelchair-dependent and three patients were ambulatory without aid. Bladder function recovered fully in five children. Most affected aspects of quality of life were physical and mental well-being and self-perception. T2-weighted-MR images showed pencil-like hyperintensity (8/8) in sagittal and H-shaped or snake-eyes-like lesion (6/8) in axial views. Analyses of all 83 patients were in congruence with the above results of the study group. CONCLUSION: Spinal cord ischaemia in childhood presenting with pain, paraplegia, and bladder dysfunction has high morbidity concerning motor problems and quality of life. Acute arterial ischaemic event in children seems similar to adult events with respect to clinical presentation and, surprisingly, also in outcome.

Mécanisme moléculaire de protection des HDLs contre le stress du réticulum endoplasmique dans la cellule beta pancréatique. [Molecular mechanisms of HDLs to protect against the endoplasmic reticulum stress in pancreatic beta cell.]

Introduction: Les particules de HDL (High Density Lipoproteins) ont des fonctions très diverses notamment anti-inflamatoires, anti-apoptotiques ou anti-oxydatives. Chez les patients diabétiques, les niveaux de HDLs sont bas, les prédisposants ainsi à un risque élévé à développer une maladie cardiovasculaire. Sachant que le s HDLs ont également un effet protecteur sur la cellule beta, le but de cette étude est dinvestigué les mécanismes moléculaires de cette protection contre le stress du réticulum, stress qui contriubue au développement du diabéte de type 2. Résultats: La thapsigargine et la tunicamycine induisent lapoptose en induisant un stress dans le réticulum endoplasmique (RE) par un mauvais repliement des protéines dans le RE, ainsi que l'activation de l'UPR (Unfolded Protein Respons) avec trois voies communes de signalisation intracellulaire (IRE1, PREK et ATF6). Ces voix veillent tout d'abord à augmenter la capacité de repliement des protéines et le cas échéant à lapoptose. Nos résultats montrent que les HDLs sont capable d'inhuber lapoptose induite par la thapsigargine et la tunicamycine dans les MIN6. Dans le cas du traitement avec la thapsigargine, plusieurs marqueurs des voix UPR sont bloqués en présence des HDLs, suggérant que l'effet anti-apoptotiques des HDLs s'exerce au niveau ou en amont du RE. Les HDLS par contre ne bloquent par la sortie de calcium du RE induite par la thapsigargine ce qui indique que les HDLs n'interfèrent pas avec l'action de cette drogue sur sa cible (SERCA). Dans le cas de la la tunicamycine, les HDLs ne bloquent pas, ou très légèrement, l'activation des voix de l'UPR. La protection induite par les HDLs contre la mort engendrée par la tunicamycine s'sexerce dont apparement en aval de l'UPR et reste à être déterminer. Conclusions: Nos données suggérent que les HDLs sont capable de protéger la cellule beta contre le stress du réticulum mais apparement de façon différente selon les modalités d'inductions de ce stress.

Video-assisted right supradiaphragmatic thoracic duct ligation for non traumatic recurrent chylothorax

Introduction : Un chylothorax est une pathologie comprenant des manifestations respiratoires, nutritionnelles et immunologiques. La récidive du chylothorax ou l'échec du traitement conservateur imposent un traitement chirurgical. Ce travail rapporte notre expérience de ligature supra-diaphragmatique, vidéo-assistée du canal thoracique, pour chylothorax récurrent non traumatique. Patients et méthodes : Entre 1999 et 2004, nous avons recensé six observations (quatre du côté droit, un du côté gauche et un bilateral) Le chylothorax s'est développé chez trois patients traités par radio et chimiothérapie pour tumeur (deux lymphomes et une tumeur du sein) un dans le contexte d'une lymphangioléiomatose et un après greffe cardiaque. Résultats : Les patients ont bénéficié sous anesthésie générale, d'une ligature du canal thoracique supra-diaphragmatique, vidéo-assistée. Le temps opératoire moyen a été de 102 minutes. Le chylothorax a régressé chez cinq des six patients en sept jours. Un patient a été repris par thoracotomie droite au huitième jour pour chylothorax persistant. Dans la phase post-opératoire, un patient a développé une détresse respiratoire nécessitant une ventilation mécanique. Un autre patient a présenté un chylopéritoine important traité par un stent de Le Veen®. Le séjour moyen a été de quatorze jours sans mortalité péri-opératoire. Conclusion : Le traitement du chylothorax non traumatique récurrent est, en première intention, un traitement médical. En cas de récidive ou d'échec du traitement conservateur, le traitement chirurgical par ligature du canal thoracique supra- diaphragmatique, vidéo-assistée, permet de traiter avec succès le chylothorax récurrent non traumatique. -- Background: Chylothorax is an uncommon disorder with respiratory, nutritional and immunological manifestations. Surgical management is indicated in case of recurrence or failure after conservative treatment. We report our experience with video-assisted right-sided supradiaphrag¬matic thoracic duct ligation for non-traumatic, non-postoperative persistent or recurrent chylothorax. Patients and methods: The medical records of six patients operated at our institution between 1999 and 2004 were retrospectively reviewed. A right-sided chylothorax was found in four patients, a left-sided in one, and a bilateral in one. Three patients developed chylothorax after chemotherapy and chest irradiation for malignant diseases (lymphoma in two patients and breast cancer in one), one in the context of lymphangioleiomyomatosis, one due to a non-diagnosed lymphoma, and one after heart transplantation. Results: The mean operative time was 102 min, with an average length of hospital stay of 14 days. Persistent cessation of chylous effusion within 7 days after surgery was observed in 5/6 patients without recurrence during a mean follow-up time of 41 months. One patient with undiagnosed mediastinal lymphoma required re-operation and thoracic duct ligation on day 8 by right-sided thoracotomy due to persistent chylothorax. No 30-day mortality was recorded. Two patients presented postoperative complications including respiratory insufficiency requiring mechanical ventilation in one, and chylous ascites development requiring peritoneo-venous LeVeen shunting in one patient. Conclusions: Recurrent or persistent non-traumatic chylothorax may be successfully treated by video-assisted right supradiaphragmatic thoracic duct ligation.

Imaging of the non-traumatic brachial plexus.

The first line imaging of the non-traumatic brachial plexus is by MRI. Knowledge of the anatomy and commonest variants is essential. Three Tesla imaging offers the possibility of 3D isotropic sequences with excellent spatial and contrast enhancement resolutions, which leads to time saving and quality boosting. The most commonly seen conditions are benign tumor lesions and radiation damage. Gadolinium is required to assess inflammatory or tumour plexopathy. MRI data should be correlated with FDG-PET if tumor recurrence is suspected.

Nitric oxide mediates the blood pressure response to mental stress in humans.

OBJECTIVE: Nitric oxide (NO) regulates arterial pressure by modulating peripheral vascular tone and sympathetic vasoconstrictor outflow. NO synthesis is impaired in several major cardiovascular disease states. Loss of NO-induced vasodilator tone and restraint on sympathetic outflow could result in exaggerated pressor responses to mental stress. METHODS: We, therefore, compared the sympathetic (muscle sympathetic nerve activity) and haemodynamic responses to mental stress performed during saline infusion and systemic inhibition of NO-synthase by NG-monomethyl-L-arginine (L-NMMA) infusion. RESULTS: The major finding was that mental stress which during saline infusion increased sympathetic nerve activity by ~50 percent and mean arterial pressure by ~15 percent had no detectable sympathoexcitatory and pressor effect during L-NMMA infusion. These findings were not related to a generalised impairment of the haemodynamic and/or sympathetic responsiveness by L-NMMA, since the pressor and sympathetic nerve responses to immersion of the hand in ice water were preserved during L-NMMA infusion. CONCLUSION: Mental stress causes pressor and sympathoexcitatory effects in humans that are mediated by NO. These findings are consistent with the new concept that, in contrast to what has been generally assumed, under some circumstances, NO has a blood pressure raising action in vivo.

Effect of multiple oral doses of androgenic anabolic steroids on endurance performance and serum indices of physical stress in healthy male subjects.

Anabolic androgenic steroids (AAS) are doping agents that are mostly used for improvement of strength and muscle hypertrophy. In some sports, athletes reported that the intake of AAS is associated with a better recovery, a higher training load capacity and therefore an increase in physical and mental performances. The purpose of this study was to evaluate, the effect of multiple doses of AAS on different physiological parameters that could indirectly relate the physical state of athletes during a hard endurance training program. In a double blind settings, three groups (n = 9, 8 and 8) were orally administered placebo, testosterone undecanoate or 19-norandrostenedione, 12 times during 1 month. Serum biomarkers (creatine kinase, ASAT and urea), serum hormone profiles (testosterone, cortisol and LH) and urinary catecholamines (noradrenalin, adrenalin and dopamine) were evaluated during the treatment. Running performance was assessed before and after the intervention phase by means of a standardized treadmill test. None of the measured biochemical variables showed significant impact of AAS on physical stress level. Data from exercise testing on submaximal and maximal level did not reveal any performance differences between the three groups or their response to the treatment. In the present study, no effect of multiple oral doses of AAS on endurance performance or bioserum recovery markers was found.

Cannabidiol attenuates cardiac dysfunction, oxidative stress, fibrosis, and inflammatory and cell death signaling pathways in diabetic cardiomyopathy.

Objectives In this study, we have investigated the effects of cannabidiol (CBD) on myocardial dysfunction, inflammation, oxidative/nitrative stress, cell death, and interrelated signaling pathways, using a mouse model of type I diabetic cardiomyopathy and primary human cardiomyocytes exposed to high glucose. Background Cannabidiol, the most abundant nonpsychoactive constituent of Cannabis sativa (marijuana) plant, exerts anti-inflammatory effects in various disease models and alleviates pain and spasticity associated with multiple sclerosis in humans. Methods Left ventricular function was measured by the pressure-volume system. Oxidative stress, cell death, and fibrosis markers were evaluated by molecular biology/biochemical techniques, electron spin resonance spectroscopy, and flow cytometry. Results Diabetic cardiomyopathy was characterized by declined diastolic and systolic myocardial performance associated with increased oxidative-nitrative stress, nuclear factor-kappa B and mitogen-activated protein kinase (c-Jun N-terminal kinase, p-38, p38 alpha) activation, enhanced expression of adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1), tumor necrosis factor-alpha, markers of fibrosis (transforming growth factor-beta, connective tissue growth factor, fibronectin, collagen-1, matrix metalloproteinase-2 and -9), enhanced cell death (caspase 3/7 and poly[adenosine diphosphate-ribose] polymerase activity, chromatin fragmentation, and terminal deoxynucleotidyl transferase dUTP nick end labeling), and diminished Akt phosphorylation. Remarkably, CBD attenuated myocardial dysfunction, cardiac fibrosis, oxidative/nitrative stress, inflammation, cell death, and interrelated signaling pathways. Furthermore, CBD also attenuated the high glucose-induced increased reactive oxygen species generation, nuclear factor-kappa B activation, and cell death in primary human cardiomyocytes. Conclusions Collectively, these results coupled with the excellent safety and tolerability profile of CBD in humans, strongly suggest that it may have great therapeutic potential in the treatment of diabetic complications, and perhaps other cardiovascular disorders, by attenuating oxidative/nitrative stress, inflammation, cell death and fibrosis. (J Am Coll Cardiol 2010;56:2115-25) (C) 2010 by the American College of Cardiology Foundation.