Effets du repas précompétitif sur la perception de l'effort et sur la glycémie lors d'un exercice de pédalage

The first purpose of the present study was to investigate the effect of three different preexercise meals on perceived exertion and glycaemia during a one-hour bicycle exercise at 80% VO₂ max. The second purpose of this study was to determine the relationship between glycaemia and perceived exertion. Eight athletes (age: 24.6 ± 2.7 years, weight: 78.0 ±6.8 kg, height: 182.6 ± 9.9 cm) completed three assessment sessions, each being preceeded by one of the following meals, ingested 3 h before exercise: 400 mL of water, 400 mL of water and 75 g of glucose, and 100 mL of water and 375 g of potatoes. The subjects 'perceived exertion were measured at times 6, 15, 30, 45, 60 min and glycaemia at 0, 30, 60 min of the exercise. The results showed that perceived exertion (RPE and ETL) of each meal increased as a function of time (P <- 0.05) whereas glycaemia did not differ except for the glucose meal between 30 min and 1 h(P < 0.02). There was no significant difference in ratings of perceived exertion among any meal whereas glycaemia was different between the three conditions only at the beginning and the middle of the exercises (P < 0.04 and P < 0.02, respectively). Moreover, the vectorial angles between the variables ofperceived exertion and the glycaemia are close to 90 °. These results would suggest that perceived exertion does not seem to be affected by the three preexercise meals used in our study. Perceived exertion is not correlated to glycaemia changes during one-hour high intensity exercise. The results would, therefore, suggest that glycaemia is not a contributor signal of perceived exertion in this study. It seems that physiological factors other than glycaemia may have mediated the perceptual intensity at exhaustion. The respiratory-metabolic signals of exertion which are most pronounced at high relative exercise intensity are suggested to influence the perceptual signal of exertion.     

Prospective randomized controlled trial comparing partially absorbable lightweight mesh and multifilament polyester anatomical mesh in laparoscopic inguinal hernia repair

Introduction

Tension‐free mesh repair is currently the gold standard treatment for inguinal hernia. Recent evidence has shown that both open and laparoscopic approaches to inguinal hernia repair can achieve good results. Lots of meshes with different properties are available on the market, but direct comparisons between them are scare. We conducted a prospective randomized controlled trial comparing a partially absorbable lightweight mesh (ULTRAPRO?) and a multifilament polyester anatomical mesh (Parietex?) in laparoscopic total extraperitoneal inguinal hernia repair.

Methods

This study was a single‐center, prospective randomized controlled trial to compare the surgical handling and clinical outcomes between two different types of meshes. All operations were performed using a standardized operative protocol. This study was approved by the Institutional Review Board of the Hong Kong East Cluster Health Service in 2009 (reference number: 2009‐087). The study was registered in the Australian New Zealand Clinical Trial Registry (ACTRN12610000031066).

Results

From October 2009 to August 2011, 85 laparoscopic total extraperitoneal inguinal hernia repairs were performed. The mean mesh handling time was 152 s for the ULTRAPRO group and 206 s for the Parietex group (P = 0.001). There were three cases of seroma formation in the ULTRAPRO group and nine in the Parietex group (P = 0.02). The overall recurrence rate was 2.5%.

Conclusion

It took less time to manipulate the flat mesh (ULTRAPRO) than the anatomical mesh (Parietex) in laparoscopic total extraperitoneal inguinal hernia repair, but the time difference was small. Lightweight mesh and heavyweight mesh offered similar clinical outcomes in terms of discomfort sensation and foreign body sensation during long‐term follow‐up.

     

TREATMENT OF INSOMNIA WITH ZALEPLON,A NOVEL SLEEP MEDICATION

Insomnia is a highly prevalent sleep problem that often results in poor daily functioning of the affected patient. Unfortunately, sedative hypnotic agents prescribed in the past often resulted in residual sedation, as well as impairment of cognitive and psychomotor performance, throughout the day after use. Newer agents with relatively rapid elimination require administration regularly each night before bedtime if symptoms of insomnia are to be prevented and next-day sedation is to be avoided. The availability of zaleplon challenges these standards of practice. The rapid elimination of zaleplon, combined with its unique receptor binding affinity, permits 10 mg of zaleplon to be taken at bedtime or later in the night with minimal concern for next-day residual effects. Clinical studies of zaleplon also identified the low risk of withdrawal syndrome or rebound insomnia after the discontinuation of nightly use. If used only on the nights when symptoms actually occur, the occurrence of such problems with zaleplon will be minimal.     

Dexamethasone during ovulation induction for in-vitro fertilization: a pilot study

The purpose of the present study was to determine whether adrenalandrogen suppression with dexamethasone (DEX) during ovulationinduction improves the outcome of in-vitro fertilization (IVF)cycles. A total of 25 patients with serum dehydroepiandrosteronesulphate (DHEAS) concentrations>2.5 µg/ml were randomizedto receive either 0.5 mg DEX daily or placebo during ovulationinduction with leuprolide acetate down-regulation plus humanmenopausal gonadotrophins (HMG). Nine patients undergoing asubsequent IVF cycle were crossed over to the other treatmentgroup. Ovarian responsiveness and IVF outcome variables analysedincluded number of follicles>12 mm in diameter, serum oestradiolconcentrations on the day of human chorionic gonadotrophin (HCG)administration, number of ampoules of HMG administered, numberof oocytes retrieved, percentage of oocytes fertilized, numberof embryos transferred, implantation rate and numbers of clinicalpregnancies and live birth pregnancies. The 31 randomized IVFcycles revealed a trend towards a higher implantation rate forthe placebo-treated group compared to the DEX-treated group(24 versus 10%P=0.07). The remainder of the IVF cycle variablesrevealed no statistically significant differences. In conclusion,the suppression of adrenal androgens with DEX in women withDHEAS concentrations >2.5 µg/ml appears to have nobeneficial effects on ovarian responsiveness or clinical orlive birth pregnancy rates.     

Prostacyclin production by perturbed bovine aortic endothelial cells in culture

This study reports that endotoxin (Escherichia coli serotype 026:B6) and 12-O-tetradecanoyl-phorbol-13-acetate stimulate cultured bovine aortic endothelial cells to generate prostacyclin. The prostacyclin concentration of the culture medium was measured indirectly by radioimmunoassay for 6-keto-PGF1 alpha. The amount of prostacyclin generated depended on the concentration of endotoxin or phorbol diester. Prostacyclin generation was not immediate, but occurred slowly after a six-hour lag period. The perturbed cells contracted and showed marked shape changes that correlated temporally with the start of enhanced prostacyclin production. Cytochalasins B and D, vinblastine, and colchicine inhibited prostacyclin production, indicating involvement of the cytoskeleton in the cellular response to endotoxin and phorbol diester. The increase in prostacyclin production was prevented by trifluoperazine, an inhibitor of the Ca++-calmodulin system, which is known to be involved in cytoskeletal function. Generation of prostacyclin was inhibited by cycloheximide and actinomycin D, indicating dependence on protein and ribonucleic acid synthesis. It is postulated that exposure to endotoxin or phorbol diester leads, via a series of reactions that involve RNA and protein synthesis and require intact cytoskeletal function, to the generation of toxic active intermediate(s) that stimulate the enzymes necessary for prostacyclin production.     

An anionic material at the advancing front of blood cells entering the bone marrow circulation

The selective entry of mature blood cells into the peripheral circulation of the bone marrow is a transcellular process. The mature blood cells penetrate the cytoplasm of the endothelial cells lining the myeloid sinuses and form a migration pore in the cell body of the lining cell, which closes after the blood cell reaches the intravascular space. The changes at the surfaces of the cells involved in this selective transcellular process were studied by means of the cationic cell surface markers colloidal iron (CI) and polycationic (high isoelectric point) ferritin (PCF). The anionic cell surface charges resulting from the presence of sialated glycoproteins remain, as shown by the application of these markers at low pH (1.8), evenly distributed at the cell surfaces of both the blood cell and the sinus lining cell. However, there is at the advancing margin of the diapedesing blood cells a marked accumulation of a nonsialated anionic material binding PCF at high pH (7.2). This material first accumulates extravascularly beneath the endothelium at an area of the blood cell surface near the site of the migration pore formation, remains at the cell surface during the initial phases of transcellular passage and disappears, either through shedding in the vascular lumen or through redistribution on the cell surface, when the cell reaches the intravascular space. This anionic material, which is neuraminidase resistant and has a pKa higher than sialic acid, is a characteristic concommitant in the selective transcellular blood cell passage in bone marrow.