Cumulative mutations in the genome of Echovirus 6 during establishment of a chronic infection in precursors of glial cells.

Although Enteroviruses are mainly described as responsible for acute diseases, their role in severe chronic pathology has been also established. Echovirus 6-like sequences have been detected by PCR analysis in central nervous system specimens from patients presenting with Amyotrophic Lateral Sclerosis. These findings suggested a persistent infection with viruses that underwent, genetic changes precluding viral particle release. To support this hypothesis, we developed a model system of Echovirus 6 chronic infection in precursors of glial cells. The nucleotide sequences of the 5'non-translated region (5'NTR), 2A and 3C regions of the virus developing persistent genome were analysed during establishment of the chronic phenotype. This study revealed that at day 160 of chronic infection, several mutations were observed: one mutation at nucleotide 108 upstream the domain II of the internal ribosome entry site (IRES) structure, one mutation at nucleotide 30 in the cloverleaf, and two mutations in the 2A region (translated in His48 to Tyr, and Ile 123 to Met). No mutations were detected in the 3C region. The impact of these mutations on viral replication have been analysed in a rabbit reticulocyte lysate (RRL) translation assay supplemented with HeLa cell lysate, and by plaque assay. Viruses with these mutations displayed a phenotype with a significant reduction of replication, while in vitro translation was not affected by the nucleotide 108 mutation. This model allowed the description of molecular changes observed in the genome of Echovirus 6 during the establishment of a chronic infection phenotype, and may be helpful for the understanding of the mechanisms leading Enteroviruses to develop chronic infections in man

Sensewear Armband for prediction of energy expenditure in controlled and free-living conditions

Sensewear Armband for prediction of energy expenditure in controlled and free-living conditions. 2. International Conference on Ambulatory Monitoring of Physical Activity and Movement (ICAMPAM 2011

3D Chemical Shift-Encoded MRI for Volume and Composition Quantification of Abdominal Adipose Tissue During an Overfeeding Protocol in Healthy Volunteers.

Overweight and obesity are major worldwide health concerns characterized by an abnormal accumulation of fat in adipose tissue (AT) and liver. To evaluate the volume and the fatty acid (FA) composition of the subcutaneous adipose tissue (SAT) and the visceral adipose tissue (VAT) and the fat content in the liver from 3D chemical-shift-encoded (CSE)-MRI acquisition, before and after a 31-day overfeeding protocol. Prospective and longitudinal study. Twenty-one nonobese healthy male volunteers. A 3D spoiled-gradient multiple echo sequence and STEAM sequence were performed at 3T. AT volume was automatically segmented on CSE-MRI between L2 to L4 lumbar vertebrae and compared to the dual-energy X-ray absorptiometry (DEXA) measurement. CSE-MRI and MR spectroscopy (MRS) data were analyzed to assess the proton density fat fraction (PDFF) in the liver and the FA composition in SAT and VAT. Gas chromatography-mass spectrometry (GC-MS) analyses were performed on 13 SAT samples as a FA composition countermeasure. Paired t-test, Pearson's correlation coefficient, and Bland-Altman plots were used to compare measurements. SAT and VAT volumes significantly increased (P < 0.001). CSE-MRI and DEXA measurements were strongly correlated (r = 0.98, P < 0.001). PDFF significantly increased in the liver (+1.35, P = 0.002 for CSE-MRI, + 1.74, P = 0.002 for MRS). FA composition of SAT and VAT appeared to be consistent between localized-MRS and CSE-MRI (on whole segmented volume) measurements. A significant difference between SAT and VAT FA composition was found (P < 0.001 for CSE-MRI, P = 0.001 for MRS). MRS and CSE-MRI measurements of the FA composition were correlated with the GC-MS results (for ndb: r <sub>MRS/GC-MS</sub>  = 0.83 P < 0.001, r <sub>CSE-MRI/GC-MS</sub>  = 0.84, P = 0.001; for nmidb: r <sub>MRS/GC-MS</sub>  = 0.74, P = 0.006, r <sub>CSE-MRI/GC-MS</sub>  = 0.66, P = 0.020) DATA CONCLUSION: The follow-up of liver PDFF, volume, and FA composition of AT during an overfeeding diet was demonstrated through different methods. The CSE-MRI sequence associated with a dedicated postprocessing was found reliable for such quantification. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1587-1599

Préparation injectable de leucine marquée au carbone 13 pour un programme de recherche clinique sur la maladie d’Alzheimer : contrôle pharmaceutique des matières premières et du produit fini et étude de stabilité

International audienceINTRODUCTION:The L-leucine labeled (L-[U-(13)C] Leu) is a stable isotopic tracer administered by parenteral route within the framework of a new clinical research program concerning the diagnosis of the Alzheimer's disease. To meet regulatory requirements and have ready to use solution with an expiration date, a pharmaceutical control of raw materials and the finished product followed by a stability study were realised.MATERIALS AND METHOD:After the pharmaceutical control of raw materials, the solution of L-[U-(13)C] Leu was prepared according to the good practices preparation. Prepared bottles were stored for 1 year of a share in a climatic chamber (25 °C±2 °C) and the other in a refrigerator (5 °C±3 °C). To assess stability, the physicochemical controls (pH, osmolality, sub-visible particles, L-[U-(13)C] Leu concentration, sodium concentration, isotopic enrichment) and microbiological (bacterial endotoxin and sterility) were performed at regular intervals for 1 year.RESULTS:Neither significant decrease of L-[U-(13)C] Leu concentration and sodium concentration nor pH and osmolality variation were observed for 1 year. Isotopic enrichment higher than 99.9% reflected the stability of labelling of L-leucine molecule. The sub-visible particles, the bacterial endotoxin and sterility were in accordance with the European pharmacopoeia attesting limpidity, apyrogenicity and sterility of this injectable preparation.DISCUSSION AND CONCLUSION:The injectable preparation of L-[U-(13)C] Leu was stable after 1 year for two preservation conditions, ensuring to safety for administration for human within the framework of this clinical research

Évaluation des besoins protéiques avant et 3 mois après chirurgie bariatrique chez des patients atteints d’obésité morbide

National audienceIntroduction : La chirurgie bariatrique chez les patients porteurs d’une obésité morbide permet une perte de poids durable, une réduction des comorbidités et une amélioration de la qualité de vie. Toutefois, elle s’accompagne de déficiences nutritionnelles, notamment d’une carence protéique capable d’engendrer une perte de la masse musculaire après la chirurgie. Cette perte protéique excessive peut limiter les effets bénéfiques du geste chirurgical. Or, le besoin protéique après chirurgie bariatrique n’est pas clairement défini. L’objectif de cette étude a donc été de déterminer le besoin en protéines de sujets obèses avant et après sleeve gastrectomie (SG) et by-pass gastrique (BPG), afin d’élaborer des recommandations précises et pratiques. Matériel & Méthodes : 19 patients obèses (IMC 43,2±1,2 kg/m²), âgés de 25 à 61 ans, ont été étudiés avant puis 3 mois après SG (n=13) ou BPG (n=6). Le besoin moyen en protéines (BMP) et l’apport protéique de sécurité (APS) de cette population ont été évalués par la mesure du bilan azoté avec 2 niveaux d’apports azotés, exprimés par kilogramme de poids corporel (kgPC) ou de masse maigre (kgMM) mesurée à l’aide de la dilution d’eau deutérée. Résultats : Le BMP de cette population avant opération est de 0,70±0.16 g/kg PC/j soit 1,38±0,31 g/kg MM/j, d’où un APS correspondant de 1,01 g/kg/j soit 2,00 g/kg MM/j. La perte de poids est de 19±1 kg 3 mois après la SG et de 19±2 kg après BPG, et les apports protéiques spontanés sont estimés à 0,39±0,04 g/kgPC/j et de 0,46±0,06 g/kgPC/j après BPG. Le calcul du BMP 3 mois après SG et BPG est de 0,60±0,15 g/kgPC/j et 0,50±0,18 g/kgPC/j respectivement, ou 1,07±0,27 g/kgMM/j et 0,89±0,18 g/kgMM/j. Les APS correspondant sont de 0,89 g/kgPoids/j et 0,85 g/kgPoids/j ou 1,60 g/kgMM/j et 1,51 g/kgMM/j. Conclusion : L’apport protéique de sécurité calculé pour les patients obèses morbides (1,01 g/kg/j) est plus élevé que pour les sujets adultes non-obèses (0,83 g/kg/j). Trois mois après la chirurgie, le besoin et l’apport protéique de sécurité diminuent quelle que soit le type de chirurgie mais les apports spontanés ne parviennent pas à couvrir les besoins en protéines. Ces résultats fournissent des arguments solides pour l’établissement de recommandations spécifiques pour les patients obèses morbides avant et après chirurgie bariatrique

Counter-regulatory responses to postprandial hypoglycaemia in patients with post-bariatric hypoglycaemia vs surgical and non-surgical control individuals.

Post-bariatric hypoglycaemia is an increasingly recognised complication of bariatric surgery, manifesting particularly after Roux-en-Y gastric bypass. While hyperinsulinaemia is an established pathophysiological feature, the role of counter-regulation remains unclear. We aimed to assess counter-regulatory hormones and glucose fluxes during insulin-induced postprandial hypoglycaemia in patients with post-bariatric hypoglycaemia after Roux-en-Y gastric bypass vs surgical and non-surgical control individuals. In this case-control study, 32 adults belonging to four groups with comparable age, sex and BMI (patients with post-bariatric hypoglycaemia, Roux-en-Y gastric bypass, sleeve gastrectomy and non-surgical control individuals) underwent a postprandial hypoglycaemic clamp in our clinical research unit to reach the glycaemic target of 2.5 mmol/l 150-170 min after ingesting 15 g of glucose. Glucose fluxes were assessed during the postprandial and hypoglycaemic period using a dual-tracer approach. The primary outcome was the incremental AUC of glucagon during hypoglycaemia. Catecholamines, cortisol, growth hormone, pancreatic polypeptide and endogenous glucose production were also analysed during hypoglycaemia. The rate of glucose appearance after oral administration, as well as the rates of total glucose appearance and glucose disappearance, were higher in both Roux-en-Y gastric bypass groups vs the non-surgical control group in the early postprandial period (all p<0.05). During hypoglycaemia, glucagon exposure was significantly lower in all surgical groups vs the non-surgical control group (all p<0.01). Pancreatic polypeptide levels were significantly lower in patients with post-bariatric hypoglycaemia vs the non-surgical control group (median [IQR]: 24.7 [10.9, 38.7] pmol/l vs 238.7 [186.3, 288.9] pmol/l) (p=0.005). Other hormonal responses to hypoglycaemia and endogenous glucose production did not significantly differ between the groups. The glucagon response to insulin-induced postprandial hypoglycaemia is lower in post-bariatric surgery individuals compared with non-surgical control individuals, irrespective of the surgical modality. No significant differences were found between patients with post-bariatric hypoglycaemia and surgical control individuals, suggesting that impaired counter-regulation is not a root cause of post-bariatric hypoglycaemia. ClinicalTrials.gov NCT04334161