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Post-traumatic stress disorder (PTSD) is a major public health problem. The most frequent complaints in this pathology are sleep disorders and trauma-related nightmares in particular. Trauma-related nightmares are characteristic of PTSD and impact its severity insofar as they are associated with more severe, longer-lasting symptoms and resistance to first-line treatments. There are specific characteristics associated with military personnel, including overrepresentation of replicative trauma-related nightmares. The aim of this study was to provide an accurate description of sleep patterns and the characteristics of trauma-related nightmares in a population of active-duty members or veterans diagnosed with PTSD.

Nanocomposites comprising bio-based polymers have become relevant in fields such as food packaging and biomedical applications. Polylactide (PLA) is a chiral and aliphatic polyester that can attain a wide range of tacticities which enables to tailor of the final material properties. However, PLA exhibits hydrophobic characteristics requiring the enhancement of its bioactivity by the generation of composites with hydrophilic materials as an approach to generate multifunctional material. Collagen is a natural and hydrophilic biopolymer that is partially hydrolyzed to obtain a material exhibiting higher solubility in aqueous solutions, namely gelatin, thus improving collagen usability. Herein, a series of free-standing films comprising different concentrations of commercial PLA and gelatin obtained from waste fisheries were produced to afford biocompatible coatings with promising biomedical applications. The multiscale structural characterization performed from the molecular scale (FTIR) to the nano-scale (SAXS/WAXS) level has been correlated with the thermal behaviour (DSC) and degradation (TGA) of the bionanocomposites generated to understand the processing conditions on the final material.

Creating flexible, high-strength hydrogels from harmless, low-cost natural polymers is an area of intense research today due to their potential applications in the biomedical field, which demands materials with ambivalent physicochemical features. In particular, great efforts were devoted to the preparation of sustainable biohydrogels, composed of hydrophilic networks of renewable, biocompatible, biodegradable, and low-cost biopolymers. Bionanocomposites are a promising synthetic approach to combine specific multifunctional materials with targeted physicochemical properties. Novel bionanocomposite hydrogels were designed by combining both chondroitin sulfate (CS) as well as gelatin (GE) obtained from the waste generated by the fish industries to form double fibre networks with tailored properties. In addition, hybrid bionanocomposites were achieved by introducing graphene nanoparticles (xGnP) into the double fibrillar network (GE/CS) to enhance the physicochemical properties. The bionanocomposite nanostructures were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) while their rheological properties and thermal stability were determined by rheological and thermogravimetric analyses (TGA), respectively. The likely interactions between CS and gelatin in the GE/CS hydrogel network were proved by ATR-FTIR spectroscopy. The incorporation of xGnP improved the mechanical properties of the GE/CS fibrillary network by an order of magnitude in the shear storage modulus. Eventually, the generated bionanocomposites hydrogels and bionanocomposite hybrid hydrogels have promising potential for applications in many biomedical fields, including drug delivery and tissue engineering by mimicking tissue extracellular matrix components such as the gelatin for collagen and the CS in the cartilage.

Polarization sensitive second harmonic generation (pSHG) microscopy has been used previously to characterize the structure of collagen fibers in corneal samples. Due to the typical organization of the corneal stroma, the information that pSHG provides may be misleading in points where two different collagen fiber bundles orient along different direction crossings. Here, a simulation that illustrates the problem is presented, along with a novel method that is capable of identifying these crossing points. These results can be used to improve the evaluation of corneal collagen structure, and it has been applied to analyze pSHG data acquired from healthy and keratoconic human corneal samples.

The last three decades have seen significant progress in our understanding of the role of the pro-survival protein BCL-2 and its family members in apoptosis and cancer. BCL-2 and other pro-survival family members including Mcl-1 and BCL-XLhave been shown to have a key role in keeping pro-apoptotic ‘effector’ proteins BAK and BAX in check. They also neutralize a group of ‘sensor’ proteins (such as BIM), which are triggered by cytotoxic stimuli such as chemotherapy. BCL-2 proteins therefore have a central role as guardians against apoptosis, helping cancer cells to evade cell death. More recently, an increasing number of BH3 mimetics, which bind and neutralize BCL-2 and/or its pro-survival relatives, have been developed. The utility of targeting BCL-2 in hematological malignancies has become evident in early-phase studies, with remarkable clinical responses seen in heavily pretreated patients. As BCL-2 is overexpressed in ~75% of breast cancer, there has been growing interest in determining whether this new class of drug could show similar promise in breast cancer. This review summarizes our current understanding of the role of BCL-2 and its family members in mammary gland development and breast cancer, recent progress in the development of new BH3 mimetics as well as their potential for targeting estrogen receptor-positive breast cancer.

Le sommeil et l’exercice physique ont une influence réciproque du fait de l’existence d’interactions complexes et bilatérales impliquant des processus à la fois physiologiques et psychologiques. Pour un individu en bonne santé, la pratique d’une activité physique régulière est considérée comme bénéfique pour le sommeil tout en dépendant de nombreux facteurs, tels que le sexe, l’âge, le niveau de forme physique, la qualité du sommeil et les caractéristiques de l’exercice (durée, intensité, heure de pratique, environnement). Sur la base de recommandations pratiques, un entraînement physique modéré de type aérobie pourrait être également prescrit comme un traitement non pharmacologique des troubles du sommeil, tels que l’insomnie et l’apnée du sommeil. L’objectif de cette synthèse est de décrire les effets physiologiques fondamentaux liant le sommeil et l’exercice dans le but d’améliorer l’utilisation de l’exercice physique comme outil thérapeutique en médecine du sommeil ainsi que pour la prévention des troubles du sommeil chez les sportifs.

Astronomical images received by ground-based telescopes are affected by atmospheric turbulence leading to optical deformations. Hence, adaptive optics systems have been developed as a way to compensate for these optical deformations before images arrive to the telescope high resolution camera. The advent of very large telescopes leads to adaptive optics systems requiring a large computational load and leading to an important time delay that deteriorates performances. Through this paper, a novel solution is explored to overcome the high computational cost of the estimation process while still attaining good performances. The aim of the proposed method is to synthesize a reduced-order filter gain using a turbulence model with large number of Zernike modes. Since the algorithm does not synthesize a full-order gain, the computational cost is significantly reduced for the synthesis and the estimation.

The aim of this study was to determine wether continuous heavy physical activities as well as lack of food and sleep during military training (three weeks of conditioning followed by a five-day combat course) alter serum concentrations of IGF-I and/or its binding proteins, evaluating the relationship to metabolic changes. Before and after training, we measured serum levels of both total and free IGF-I, IGFBP-1 and IGFBP-3 as well as plasma levels of branched-chain amino acids (valine, leucine and isoleucine) and glucose from 26 cadets (21 ± 2 yr). Total and free IGF-I levels were decreased after training from 228 ± 12 to 160 ± 7 ng/ml and from 0.80 ± 0.08 to 0.52 ± 0.06 ng/ml, p < 0.001 respectively) as well as IGFBP-3 (p < 0.001), while IGFBP-1 levels were increased (p < 0.001). BCAA levels were decreased from 245.4 ± 7.5 to 215.9 ± 5.1 µmol/l, p < 0.001, while those of glucose remained unchanged. There were correlations between changes in total IGF-I and IGFBP-3 (p < 0.05) and between free IGF-I and IGFBP-1 (p < 0.01). Several correlations appeared between changes in all the components of the IGF-I axis and branched-chain amino acids. We concluded that responses of the IGF-I system during an intense training could represent an adaptative response to the encountered energy deficiency, resulting a diversion of substrate from growth to acute metabolic needs.

The use of chronic low frequency stimulations (CLFS, 10 Hz bipolar current 8 h · day-1) as a countermeasure against unweighting-induced muscle alterations was investigated in rat soleus muscle during 21 days of hindlimb suspension (HS). It was shown that CLFS was able to minimize the soleus muscle atrophy induced by suspension (-29% in stimulated muscles compared to -56% in the non-stimulated soleus muscle). In parallel, CLFS partly prevented the HS-induced decreases in the cross-sectional area of type I fibres and in the total and myofibril protein contents. Stimulation at low frequency reduced the increase in the fast-myosin expression recorded with unweighting. Moreover, the HS-induced increase in glycolytic capacity was counteracted to a considerable extent by CLFS. In conclusion, the results of this study showed that CLFS can only partly prevent the HS-induced modifications in the soleus muscle. However, the limited effectiveness of CLFS to prevent muscle atrophy emphasized the critical role of reduced load bearing in the induction of solens muscle atrophy.

To examine the effects of growth hormone (GH) on the preferential atrophy of the soleus muscle (SOL) occurring after hindlimb suspension (HS), two groups of male rats received daily injections of 2 IU · kg -1 body mass of recombinant human growth hormone (rhGH). Rats were either suspended by the tail for 21 days (HS-GH, n = 5) or nonsuspended (CGH, n=5). The effects of rhGH treatment on SOL and extensor digitorum longus muscles (EDL) were compared in two groups of animals receiving daily injections of saline, either suspended by the tail (HS-SA, n = 5) or nonsuspended (C-SA, n = 5). The results showed that the SOL hypertrophy in response to rhGH administration was mostly observed in C rats (+33%, P<0.01). This increase in muscle mass was correlated with a concomitant increase in the size of type I fibres (+21%, P<0.05). Although SOL mass decreased during HS in rhGH treated animals (-44%, P<0.001), the mean normalized mass of this muscle did not significantly differ between C-SA and HS-GH groups. A statistically significant increase in the absolute mass of EDL occurred with rhGH treatment in CGH (+12%, P<0.05). The HS-induced decrease in the percentage distribution of type I fibres in SOL was unaffected by the rhGH treatment. In addition, a decrease in the citrate synthase activity in the whole SOL was observed in the two groups of tail-suspended rats (-31%, P<0.05; -21%, P<0.05 in SA and GH animals, respectively). The activity of 3-hydroxyacyl coenzyme A dehydrogenase was enhanced by the rhGH treatment (P<0.05) with similar magnitude in both C (+25%) and HS rats (+24%). Therefore, GH prevented only slightly the atrophy of SOL, occurring after 21 days of HS. The effects of rhGH treatment appeared most effective in C rats, suggesting that HS impaired the growth-promoting effects of this hormone on skeletal muscle.

Four groups of rats were subjected to the following conditions: (1) 48 h fasting, (2) 48 h of 4°C cold exposure, (3) 5 h treadmill running, (4) 48 h fasting with 4°C cold exposure. The groups were compared to fed control rats in order to study hormonal and metabolic responses in blood and tissue samples. Isolated hepatocytes were used to evaluate the rate of ketogenesis. Decreases in liver glycogen and increases in blood free fatty acids (FFA) confirmed that glycogenolysis and lipolysis occur in these situations of metabolic stress. Increases in the glucagon/insulin plasma ratio were also noted. Plasma catecholamine levels were only enhanced after running and after cold exposure. Production of blood ketone bodies was stimulated more by running and by fasting than by cold exposure. The low ketone body production observed after cold exposure seems to be linked to increases liver glycogen levels and decreased FFA availability. Liver cells isolated after cold exposure exhibited higher ketogenesis than these isolated after running. This difference in ketogenic capacity could result both from the longer hormonal stimulation by high glucagon/insulin plasma ratios and from the metabolic state of the liver.

Summary: Prolonged physical exercise and fasting in male rats were studied to determine the effect of these two treatments on plasma testosterone level. Blood and tissue samples were drawn after 1 h, 3 h, 5 h, and 7 h treadmill running, and after 24 h, 48 h, and 72 h of fasting. Both treatments resulted in a significant fall in plasma testosterone, plasma luteinizing hormone (LH), plasma Insulin (IRI) and in liver and muscle glycogen stores. In the course of these two treatments the injection of a supra maximal dose of Human Chorionic Gonadotropin (HCG) produced a rise in plasma testosterone similar to that in control rats. This indicates that the decrease of plasma LH may be responsible for the decrease in plasma testosterone, which is time-related with the decrease in glycogen stores. The possible metabolic role of the decrease in plasma testosterone is discussed.

The expression of myosin isoforms was studied in regenerated rat soleus muscle during either normal or altered postural activity. Regeneration was induced following injury by venom from the Notechis scutatus scutatus snake. Immunohistochemical analysis showed that, in regenerating soleus muscle after 3 wk of hindlimb suspension, nearly all fibers reacted positively with the myosin heavy chain (MHC) antibody associated with fast-twitch muscle fibers (fast MHC). When 3 wk of recovery with normal weight-bearing activity followed hindlimb suspension, the regeneration soleus muscle exhibited a nearly homogeneous staining with the MHC antibody associated with the slow-twitch muscle fibers (slow MHC). These findings were in accordance with quantitative analysis of the electrophoretic separation of the native myosin isoforms. Immunohistochemical data showed that removal of weight bearing in the 21-day old regenerated soleus muscles resulted in an increase in fast MHC expression. Together, the results of the present study clearly demonstrate that the postural load is an important component in the induction of slow MHC in regenerating muscle and that the control of the expression of MHC in muscle comprising a homogeneous population of fibers deriving from satellite cells appears more homogeneous and more complete than in a nondegenerated one.

The aim of this study was to determine the MHC profile of regenerated soleus muscles in control (C, n= 8) and hindlimb suspended rats (HS, n= 8). After muscle degeneration was induced by injection of snake venom containing notexin, male rats were either tail suspended for 21 days or submitted to normal weight‐bearing activity. Separation and detection of MHCs by sodium dodecyl sulphate–polyarcylamide gel electrophoresis (SDS–PAGE) showed that regenerated soleus muscles from C rats contained only type I and type IIa MHCs. The relative amount of type I MHC was higher in regenerated (93.9 ± 1.7%) than in untreated muscles (86.5 ± 2.3%) (P< 0.01). In the HS group, the immunohistochemical analysis showed that the majority of regenerated myofibres reacted positively with the antibody against fast MHCs. SDS–PAGE analysis demonstrated that HS resulted in a shift toward faster MHCs in both intact and regenerated myofibres. Regenerated soleus muscle from HS rats contained ≈34% type IIa MHC, ≈37% type IIx/d MHC and ≈18% type IIb MHC, when type I MHC contributed to only ≈12% of total myosin. The proportions of fast MHC isoforms in regenerated muscles were higher than those recorded in untreated muscles. Collectively, these results suggest that the shift in the MHC profile associated with hindlimb unweighting in adult undamaged soleus muscles is also related to the heterogeneity of early myoblasts.

Summary Previous studies have shown a decrease in plasma testosterone during prolonged physical exercise and 72 h fasting in rats.

Summary Fusaric acid (FA) administration to the rats promoted one hour later a large decrease in plasma total tryptophan (TRP), without affecting either plasma free TRP or lipolysis, as measured by plasma non esterified fatty acid concentration. The previous change was associated with hypoinsulinemia, hyperglycemia and increased plasma corticosterone level. Regression analysis revealed a significant correlation between brain TRP and the percentage of plasma TRP which was free (i.e. unbound to albumin), both increased by FA injection. The increase in brain TRP promoted an increased brain serotonin synthesis, as measured by the enhanced brain and CSF 5-HIAA levels. Valine pretreatment, which blocks TRP entry into the brain, completely prevented FA-induced brain TRP and brain 5-HIAA increases.

ABSTRACTA prospective, multicenter study was carried out over a period of 10 months. All patients with clinically significant bacteremia caused by Enterococcusspp. were included. The epidemiological, microbiological, clinical, and prognostic features and the relationship of these features to the presence of high-level resistance to gentamicin (HLRG) were studied. Ninety-three patients with enterococcal bacteremia were included, and 31 of these cases were caused by HLRG (33%). The multivariate analysis selected chronic renal failure, intensive care unit stay, previous use of antimicrobial agents, andEnterococcus faecalisspecies as the independent risk factors that influenced the development of HLRG. The strains with HLRG showed lower levels of susceptibility to penicillin and ciprofloxacin. Clinical features (except for chronic renal failure) were similar in both groups of patients. HLRG did not influence the prognosis for patients with enterococcal bacteremia in terms of either the crude mortality rate (29% for patients with bacteremia caused by enterococci with HLRG and 28% for patients not infected with strains with HLRG) or the hospital stay after the acquisition of enterococcal bacteremia. Hemodynamic compromise, inappropriate antimicrobial therapy, and mechanical ventilation were revealed in the multivariate analysis to be the independent risk factors for mortality. Prolonged hospitalization was associated with the nosocomial acquisition of bacteremia and polymicrobial infections.

We examined the extent of morphological alterations and the myosin heavy chain (MHC) distribution in the rat soleus muscle after a 4-week period of spontaneous recovery or retraining after hindlimb suspension (HS). Moreover, we tested the hypothesis that dantrolene sodium, which affects the flux of calcium over the sarcoplasmic reticulum membrane, was able to attenuate muscle damage. Three groups of rats were submitted to 3 weeks of HS, followed by either 4 weeks of unrestricted cage activity (HC, n?=?7), or running training for the same period and were compared to age-matched animals (C, n?=?8). Trained rats were treated with either placebo or dantrolene sodium (HTP, HTD, n?=?8 each, respectively). Four weeks after HS recovery, the percentage of myofibres with internal nuclei (%in) was determined by histological staining with hematoxylin and eosin. %in was affected by the individual rat ( P?

The aim of this study was to quantify the degenerative and regenerative changes in rat soleus muscle resulting from 3-week hindlimb suspension at 45° tilt (HS group, n?=?8) and 4-week normal cage recovery (HS-R group, n?=?7). Degenerative changes were quantified by microscope examination of muscle cross sections, and the myosin heavy chain (MHC) composition of soleus muscles was studied by sodium dodecyl sulphate polyacrylamide gel electrophoresis. At the end of 3-week hindlimb suspension, histological signs of muscle degenerative changes were detected in soleus muscles. There was a significant variability in the percentage of fibres referred to as degenerating (%dg) in individual animals in the HS group [%dg?=?8.41 (SEM 0.5)%, range 4.66%–14.08%]. Moreover, %dg varied significantly along the length of the soleus muscle. The percentage of fibres with internal nuclei was less than %dg in HS-soleus muscles [4.12 (SEM 0.3)%, range 1.24%–8.86%]. In 4-week recovery rats, the greater part of the fibres that were not referred to as normal, retained central nuclei [15.8 (SEM 2.2)%, range 6.2%–21.1%]. A significant increase in the slow isoform of MHC was recorded in the HS-R rats, compared to muscles from age-matched rats ( P?

Évaluer l’association entre les maladies chroniques et la sieste.

Le syndrome de l’intestin irritable (SII) représente la plus fréquente des affections intestinales. Son lien avec le stress, ses conséquences sur le sommeil, la qualité de vie et le fonctionnement professionnel sont reconnus. L’objectif est d’analyser l’impact du télétravail (TT) sur une population de salariés souffrant de SII.

Le syndrome Ehlers Danlos (SED) regroupe un ensemble pathologique héréditaire touchant le tissu conjonctif. Dans la forme hypermobile (SED type III selon la classification de Villefrance) les troubles du sommeil sont fréquents et participent de l’altération de la qualité de vie. L’objectif de cette étude est d’analyser la macro et microstructure du sommeil des SED/III.

Évaluer les effets de 3 jours de soins en thalassothérapie sur le sommeil, les capacités mentales et physiques, et leurs bénéfices après une semaine de reprise d’activité professionnelle.