Multifocalité du carcinome épidermoïde sur les voies digestive supérieure et respiratoire distale : technicité du diagnostic endoscopique [Multiple squamous cell carcinoma of the upper digestive and lower respiratory tracts : methodology of endoscopic screening]

L'étude porte sur 951 porteurs d'un cancer primaire bucco-pharyngo-laryngé, et révèle un taux de multifocalité du carcinome épidermoïde sur les voies digestive supérieure (bouche-pharynx-oesophage) et aérienne distale (larynx-trachée-bronches) s'élevant à 14,5 %. Les secondes localisations peuvent être simultanées (6,4 %) ou successives (8,1 %) à la découverte du premier cancer: dès la deuxième année du follow-up leur incidence dépasse celle des récidives. Elles se localisent tant au niveau ORL (8,5 %) qu'oesophagien (3 %) ou bronchique (3 %). Le cancer du voile présente un taux de multifocalité particulièrement élevé (51 %). Les auteurs décrivent un type d'endoscopie de dépistage (bucco-pharyngo-oesophago-laryngo-trachéobronchoscopie) dont la fiabilité repose sur une technicité spécifique d'une part, et sur la connaissance des caractéristiques propres aux secondes localisations d'autre part. Ce dépistage systématique permet de détecter les tumeurs secondaires à un stade le plus souvent précoce et encore asymptomatique.

Assessing dystrophies and other muscle diseases at the nanometer scale by atomic force microscopy.

AIM: Atomic force microscopy nanoindentation of myofibers was used to assess and quantitatively diagnose muscular dystrophies from human patients. MATERIALS & METHODS: Myofibers were probed from fresh or frozen muscle biopsies from human dystrophic patients and healthy volunteers, as well as mice models, and Young's modulus stiffness values were determined. RESULTS: Fibers displaying abnormally low mechanical stability were detected in biopsies from patients affected by 11 distinct muscle diseases, and Young's modulus values were commensurate to the severity of the disease. Abnormal myofiber resistance was also observed from consulting patients whose muscle condition could not be detected or unambiguously diagnosed otherwise. DISCUSSION & CONCLUSION: This study provides a proof-of-concept that atomic force microscopy yields a quantitative read-out of human muscle function from clinical biopsies, and that it may thereby complement current muscular dystrophy diagnosis.

Respiratory variability in mechanically ventilated patients. Critical Care 2011

Introduction: Increased respiratory pattern variability is associated with improved oxygenation. Pressure support (PS) is a widely used partial-assist mechanical ventilation (MV) mode, in which each breathing cycle is initiated by flow or pressure variation at the airway due to patient inspiratory effort. Neurally adjusted ventilatory assist (NAVA) is relatively new and uses the electrical activity of the diaphragm (Eadi) to deliver ventilatory support proportional to the patient's inspiratory demand. We hypothesize that respiratory variability should be greater with NAVA compared with PS.Methods: Twenty-two patients underwent 20 minutes of PS followed by 20 minutes of NAVA. Flow and Eadi curves were used to obtain tidal volume (Vt) and ∫Eadi for 300 to 400 breaths in each patient. Patient-specific cumulative distribution functions (CDF) show the percentage Vt and ∫Eadi within a clinically defined (±10%) variability band for each patient. Values are normalized to patient-specific medians for direct comparison. Variability in Vt (outcome) is thus expressed in terms of variability in ∫Eadi (demand) on the same plot.Results: Variability in Vt relative to variability in ∫Eadi is significantly greater for NAVA than PS (P = 0.00012). Hence, greater variability in outcome Vt is obtained for a given demand in ∫Eadi, under NAVA, as illustrated in Figure 1 for a typical patient. A Fisher 2 × 2 contingency analysis showed that 45% of patients under NAVA had a Vt variability in equal proportion to ∫Eadi variability, versus 0% for PS (P < 0.05).Conclusions: NAVA yields greater variability in tidal volume, relative to ∫Eadi demand, and a better match between Vt and ∫Eadi. These results indicate that NAVA could achieve improved oxygenation compared with PS when sufficient underlying variability in ∫Eadi is present, due to its ability to achieve higher tidal volume variability from a given variability in ∫Eadi.

Rhinovirus Genome Variation during Chronic Upper and Lower Respiratory Tract Infections.

Routine screening of lung transplant recipients and hospital patients for respiratory virus infections allowed to identify human rhinovirus (HRV) in the upper and lower respiratory tracts, including immunocompromised hosts chronically infected with the same strain over weeks or months. Phylogenetic analysis of 144 HRV-positive samples showed no apparent correlation between a given viral genotype or species and their ability to invade the lower respiratory tract or lead to protracted infection. By contrast, protracted infections were found almost exclusively in immunocompromised patients, thus suggesting that host factors rather than the virus genotype modulate disease outcome, in particular the immune response. Complete genome sequencing of five chronic cases to study rhinovirus genome adaptation showed that the calculated mutation frequency was in the range observed during acute human infections. Analysis of mutation hot spot regions between specimens collected at different times or in different body sites revealed that non-synonymous changes were mostly concentrated in the viral capsid genes VP1, VP2 and VP3, independent of the HRV type. In an immunosuppressed lung transplant recipient infected with the same HRV strain for more than two years, both classical and ultra-deep sequencing of samples collected at different time points in the upper and lower respiratory tracts showed that these virus populations were phylogenetically indistinguishable over the course of infection, except for the last month. Specific signatures were found in the last two lower respiratory tract populations, including changes in the 5'UTR polypyrimidine tract and the VP2 immunogenic site 2. These results highlight for the first time the ability of a given rhinovirus to evolve in the course of a natural infection in immunocompromised patients and complement data obtained from previous experimental inoculation studies in immunocompetent volunteers.

NCoR1 is a conserved physiological modulator of muscle mass and oxidative function.

Transcriptional coregulators control the activity of many transcription factors and are thought to have wide-ranging effects on gene expression patterns. We show here that muscle-specific loss of nuclear receptor corepressor 1 (NCoR1) in mice leads to enhanced exercise endurance due to an increase of both muscle mass and of mitochondrial number and activity. The activation of selected transcription factors that control muscle function, such as MEF2, PPARβ/δ, and ERRs, underpins these phenotypic alterations. NCoR1 levels are decreased in conditions that require fat oxidation, resetting transcriptional programs to boost oxidative metabolism. Knockdown of gei-8, the sole C. elegans NCoR homolog, also robustly increased muscle mitochondria and respiration, suggesting conservation of NCoR1 function. Collectively, our data suggest that NCoR1 plays an adaptive role in muscle physiology and that interference with NCoR1 action could be used to improve muscle function.

The relationship between monocarboxylate transporters 1 and 4 expression in skeletal muscle and endurance performance in athletes

The purpose of this study was to examine the relationship between skeletal muscle monocarboxylate transporters 1 and 4 (MCT1 and MCT4) expression, skeletal muscle oxidative capacity and endurance performance in trained cyclists. Ten well-trained cyclists (mean +/- SD; age 24.4 +/- 2.8 years, body mass 73.2 +/- 8.3 kg, VO(2max) 58 +/- 7 ml kg(-1) min(-1)) completed three endurance performance tasks [incremental exercise test to exhaustion, 2 and 10 min time trial (TT)]. In addition, a muscle biopsy sample from the vastus lateralis muscle was analysed for MCT1 and MCT4 expression levels together with the activity of citrate synthase (CS) and 3-hydroxyacyl-CoA dehydrogenase (HAD). There was a tendency for VO(2max) and peak power output obtained in the incremental exercise test to be correlated with MCT1 (r = -0.71 to -0.74; P < 0.06), but not MCT4. The average power output (P (average)) in the 2 min TT was significantly correlated with MCT4 (r = -0.74; P < 0.05) and HAD (r = -0.92; P < 0.01). The P (average) in the 10 min TT was only correlated with CS activity (r = 0.68; P < 0.05). These results indicate the relationship between MCT1 and MCT4 as well as cycle TT performance may be influenced by the length and intensity of the task.

Activity of the δ-Opioid Receptor Is Partially Reduced, Whereas Activity of the κ-Receptor Is Maintained in Mice Lacking the μ-Receptor

Previous pharmacological studies have indicated the possible existence of functional interactions between μ-, δ- and κ-opioid receptors in the CNS. We have investigated this issue using a genetic approach. Here we describe in vitro and in vivo functional activity of δ- and κ-opioid receptors in mice lacking the μ-opioid receptor (MOR). Measurements of agonist-induced [35S]GTPγS binding and adenylyl cyclase inhibition showed that functional coupling of δ- and κ-receptors to G-proteins is preserved in the brain of mutant mice. In the mouse vas deferens bioassay, deltorphin II and cyclic[d-penicillamine2,d-penicillamine5] enkephalin exhibited similar potency to inhibit smooth muscle contraction in both wild-type and MOR −/− mice. δ-Analgesia induced by deltorphin II was slightly diminished in mutant mice, when the tail flick test was used. Deltorphin II strongly reduced the respiratory frequency in wild-type mice but not in MOR −/− mice. Analgesic and respiratory responses produced by the selective κ-agonist U-50,488H were unchanged in MOR-deficient mice. In conclusion, the preservation of δ- and κ-receptor signaling properties in mice lacking μ-receptors provides no evidence for opioid receptor cross-talk at the cellular level. Intact antinociceptive and respiratory responses to the κ-agonist further suggest that the κ-receptor mainly acts independently from the μ-receptor in vivo. Reduced δ-analgesia and the absence of δ-respiratory depression in MOR-deficient mice together indicate that functional interactions may take place between μ-receptors and central δ-receptors in specific neuronal pathways.

Development of a new chlamydiales-specific real-time PCR and its application to respiratory clinical samples.

Originally composed of the single family Chlamydiaceae, the Chlamydiales order has extended considerably over the last several decades. Chlamydia-related bacteria were added and classified into six different families and family-level lineages: the Criblamydiaceae, Parachlamydiaceae, Piscichlamydiaceae, Rhabdochlamydiaceae, Simkaniaceae, and Waddliaceae. While several members of the Chlamydiaceae family are known pathogens, recent studies showed diverse associations of Chlamydia-related bacteria with human and animal infections. Some of these latter bacteria might be of medical importance since, given their ability to replicate in free-living amoebae, they may also replicate efficiently in other phagocytic cells, including cells of the innate immune system. Thus, a new Chlamydiales-specific real-time PCR targeting the conserved 16S rRNA gene was developed. This new molecular tool can detect at least five DNA copies and show very high specificity without cross-amplification from other bacterial clade DNA. The new PCR was validated with 128 clinical samples positive or negative for Chlamydia trachomatis or C. pneumoniae. Of 65 positive samples, 61 (93.8%) were found to be positive with the new PCR. The four discordant samples, retested with the original test, were determined to be negative or below detection limits. Then, the new PCR was applied to 422 nasopharyngeal swabs taken from children with or without pneumonia; a total of 48 (11.4%) samples were determined to be positive, and 45 of these were successfully sequenced. The majority of the sequences corresponded to Chlamydia-related bacteria and especially to members of the Parachlamydiaceae family.

Incidence and outcomes of respiratory viral infections in lung transplant recipients: a prospective study.

BACKGROUND: The incidence and outcomes of respiratory viral infections in lung transplant recipients (LTR) are not well defined. The objective of this prospective study conducted from June 2008 to March 2011 was to characterise the incidence and outcomes of viral respiratory infections in LTR. METHODS: Patients were seen in three contexts: study-specific screenings covering all seasons; routine post-transplantation follow-up; and emergency visits. Nasopharyngeal specimens were collected systematically and bronchoalveolar lavage (BAL) was performed when clinically indicated. All specimens underwent testing with a wide panel of molecular assays targeting respiratory viruses. RESULTS: One hundred and twelve LTR had 903 encounters: 570 (63%) were screening visits, 124 (14%) were routine post-transplantation follow-up and 209 (23%) were emergency visits. Respiratory viruses were identified in 174 encounters, 34 of these via BAL. The incidence of infection was 0.83 per patient-year (95% CI 0.45 to 1.52). The viral infection rates upon screening, routine and emergency visits were 14%, 15% and 34%, respectively (p<0.001). Picornavirus was identified most frequently in nasopharyngeal (85/140; 60.7%) and BAL specimens (20/34; 59%). Asymptomatic viral carriage, mainly of picornaviruses, was found at 10% of screening visits. Infections were associated with transient lung function loss and high calcineurin inhibitor blood levels. The hospitalisation rate was 50% (95% CI 30% to 70.9%) for influenza and parainfluenza and 16.9% (95% CI 11.2% to 23.9%) for other viruses. Acute rejection was not associated with viral infection (OR 0.4, 95% CI 0.1 to 1.3). CONCLUSIONS: There is a high incidence of viral infection in LTR; asymptomatic carriage is rare. Viral infections contribute significantly to this population's respiratory symptomatology. No temporal association was observed between infection and acute rejection.

Upregulation of vasopressin V1A receptor mRNA and protein in vascular smooth muscle cells following cyclosporin A treatment.

1. The major side effects of the immunosuppressive drug cyclosporin A (CsA) are hypertension and nephrotoxicity. It is likely that both are caused by local vasoconstriction. 2. We have shown previously that 20 h treatment of rat vascular smooth muscle cells (VSMC) with therapeutically relevant CsA concentrations increased the cellular response to [Arg8]vasopressin (AVP) by increasing about 2 fold the number of vasopressin receptors. 3. Displacement experiments using a specific antagonist of the vasopressin V1A receptor (V1AR) showed that the vasopressin binding sites present in VSMC were exclusively receptors of the V1A subtype. 4. Receptor internalization studies revealed that CsA (10(-6) M) did not significantly alter AVP receptor trafficking. 5. V1AR mRNA was increased by CsA, as measured by quantitative polymerase chain reaction. Time-course studies indicated that the increase in mRNA preceded cell surface expression of the receptor, as measured by hormone binding. 6. A direct effect of CsA on the V1AR promoter was investigated using VSMC transfected with a V1AR promoter-luciferase reporter construct. Surprisingly, CsA did not increase, but rather slightly reduced V1AR promoter activity. This effect was independent of the cyclophilin-calcineurin pathway. 7. Measurement of V1AR mRNA decay in the presence of the transcription inhibitor actinomycin D revealed that CsA increased the half-life of V1AR mRNA about 2 fold. 8. In conclusion, CsA increased the response of VSMC to AVP by upregulating V1AR expression through stabilization of its mRNA. This could be a key mechanism in enhanced vascular responsiveness induced by CsA, causing both hypertension and, via renal vasoconstriction, reduced glomerular filtration.

Hypolipidemic therapeutics and muscle metabolism

Summary : Lipid metabolism disorders, leading to obesity and cardiovascular diseases, are a major public health issue worldwide. These diseases have been treated by drugs and surgery, leading to tremendous costs and secondary morbidity. The aim of this thesis work is to investigate the mechanisms of actions of a new, micronutrition-based, approach to prevent obesity and cardiovascular diseases. This specific combination of micronutrients, Lipistase, incorporated into any dietary ail can be used in the daily food. Micronutrients are substances used by the living organism in small quantities to maintain physiological homeostasis. However, the human body is not able to produce them and has to obtain them from dietary sources. The combination of micronutrients investigated here, is composed of 26 compounds including trace elements, vitamins, minerals, ails and plant extracts, known to have individually a beneficial effect on lipid metabolism regulation. These specific micronutrients are used for the first time in a combinatorial mode targeting several metabolic pathways for better homeostasis control as opposed to a single target treatment, either chemical or natural. Short and long term studies, in different mouse strains, showed a significant decrease in plasma triglycerides, body weight gain and body fat mass in animals that were fed with a standard diet containing Lipistase. Additionally, a greatly reduced fat accumulation was observed in adipose tissue and liver of Lipistase-treated animals, while lipid and glucose utilization by skeletal muscle was enhanced. Moreover, the size of atherosclerotic plaques was significantly reduced in mice whose masher was treated during pregnancy and suckling, without showing any adverse effect. Finally, Lipistase has been shown to increase longevity by 20%. The control mice that did not receive Lipistase in their diet did not show all these beneficial effects. These micronutrients are used at the lowest dosage ever reported for treating Lipid disorders, resulting in far much lower costs as well as probably a higher safety. This is the first approach being very suitable for an effective large scale prevention policy for obesity and cardiovascular diseases, like iodine in dietary salt has been for goiter. Résumé : Les dysrégulations du métabolisme des lipids, à l'origine d'obésité et de maladies cardiovasculaires, sont un problème de santé publique majeur et mondial. Ces maladies impliquent des traitements médicamenteux et chirurgicaux dont le coût la morbidité secondaire sont très important. Le but de ce travail de thèse est d'étudier les mécanismes d'action d'une nouvelle approche préventive, basée sur la micronutrition. Cette combinaison spécifique de micronutriments, Lipistase, peut être incorporée dans n'importe quelle huile alimentaire et utilisée dans l'alimentation quotidienne. Les micronutrirnents sont des substances essentielles, à très faibles doses, pour le maintien de l'homéostasie physiologique des organismes vivants. Cependant, étant incapable de les synthétiser, le corps humain est dépendant en cela de l'apport alimentaire. La combinaison de micronutriments que nous avons étudié contient 26 composants, incluant des extraits de plantes, des huiles, des vitamines, des métaux et des minéraux, tous connus pour avoir individuellement des effets bénéfiques sur la régulation du métabolisme des lipides. Ces micronutriments spécifiques sont utilisés pour la première fois en mode combinatoire, ciblant ainsi plusieurs voies métaboliques pour un meilleur control de l'homéostasie, par opposition monothérapies chimiques ou naturelles. Des expériences de court et long terme, avec divers modèles de souris, ont montré une diminution significative des taux de triglycérides plasmatiques, de la prise de poids et de la masse graisseuse corporelle chez les animaux qui ont reçu Lipistase dans la nourriture standard. Une accumulation significativement moins importante des graisses a été observée dans le tissu adipeux et hépatique des souris traitées, alors que l'utilisation des lipides et glucose a été favorisée dans le muscle. En outre, la taille des plaques d'athérosclérose aété significativement réduite chez les souris dont la mère a été traitée pendant la grossesse et l'allaitement, sans montrer aucun effet indésirable. Enfin, les souris traitées par Lipistase ont vécu 20% plus longtèmps. Les souris contrôles qui n'ont pas reçu Lipistase dans la nourriture n'ont montré aucun de ces effets bénéfiques. Ces micronutriments sont utilisés au dosage le plus faible jamais rapporté pour le traitement des maladies du métabolisme lipidique, permettant ainsi un coût plus faible et surtout une meilleure sécurité. C'est une approche adéquate pour une politique de prévention de santé publique à large échelle de l'obésité et des maladies cardiovasculaires. C'est en cela et sous bien d'autres aspects, une première dans la prise en charge des maladies du métabolisme lipidique et pourrait même être pour ces dernières ce que l'iode du sel de cuisine a été pour le goitre.

Myostatin augments muscle-specific ring finger protein-1 expression through an NF-kB independent mechanism in SMAD3 null muscle.

Smad (Sma and Mad-related protein) 2/3 are downstream signaling molecules for TGF-β and myostatin (Mstn). Recently, Mstn was shown to induce reactive oxygen species (ROS) in skeletal muscle via canonical Smad3, nuclear factor-κB, and TNF-α pathway. However, mice lacking Smad3 display skeletal muscle atrophy due to increased Mstn levels. Hence, our aims were first to investigate whether Mstn induced muscle atrophy in Smad3(-/-) mice by increasing ROS and second to delineate Smad3-independent signaling mechanism for Mstn-induced ROS. Herein we show that Smad3(-/-) mice have increased ROS levels in skeletal muscle, and inactivation of Mstn in these mice partially ablates the oxidative stress. Furthermore, ROS induction by Mstn in Smad3(-/-) muscle was not via nuclear factor-κB (p65) signaling but due to activated p38, ERK MAPK signaling and enhanced IL-6 levels. Consequently, TNF-α, nicotinamide adenine dinucleotide phosphate oxidase, and xanthine oxidase levels were up-regulated, which led to an increase in ROS production in Smad3(-/-) skeletal muscle. The exaggerated ROS in the Smad3(-/-) muscle potentiated binding of C/EBP homology protein transcription factor to MuRF1 promoter, resulting in enhanced MuRF1 levels leading to muscle atrophy.

Latissimus dorsi muscle-flap over Gore-Tex patch for coverage of large thoracic defects in paediatric Ewing sarcoma.

Primary rib involvement accounts for 16% of paediatric Ewing sarcoma (ES). Neo-adjuvant chemotherapy and surgical tumor resection may leave large thoracic wall defects requiring complex reconstruction in a growing individual. We report our experience in three children aged 3, 10, and 12 years, in whom single-stage resection and reconstruction were performed using a Gore-Tex Dualmesh patch, covered by a latissimus dorsi rotation flap harvested in continuity with the thoracolumbar fascia. The youngest patient also had a vertical expandable prosthetic titanium rib (VEPTR) anchored to help prevent subsequent scoliosis throughout growth.