Peripheral Sensitization Increases Opioid Receptor Expression And Activation By Crotalphine In Rats

Inflammation enhances the peripheral analgesic efficacy of opioid drugs, but the mechanisms involved in this phenomenon have not been fully elucidated. Crotalphine (CRP), a peptide that was first isolated from South American rattlesnake C.d. terrificus venom, induces a potent and long-lasting anti-nociceptive effect that is mediated by the activation of peripheral opioid receptors. Because the high efficacy of CRP is only observed in the presence of inflammation, we aimed to elucidate the mechanisms involved in the CRP anti-nociceptive effect induced by inflammation. Using real-time RT-PCR, western blot analysis and ELISA assays, we demonstrate that the intraplantar injection of prostaglandin E2 (PGE2) increases the mRNA and protein levels of the μ- and κ-opioid receptors in the dorsal root ganglia (DRG) and paw tissue of rats within 3 h of the injection. Using conformation state-sensitive antibodies that recognize activated opioid receptors, we show that PGE 2, alone does not increase the activation of these opioid receptors but that in the presence of PGE2, the activation of specific opioid receptors by CRP and selective μ- and κ-opioid receptor agonists (positive controls) increases. Furthermore, PGE2 down-regulated the expression and activation of the δ-opioid receptor. CRP increased the level of activated mitogen-activated protein kinases in cultured DRG neurons, and this increase was dependent on the activation of protein kinase Cζ. This CRP effect was much more prominent when the cells were pretreated with PGE 2. 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Precision of 1-RM prediction equations in non-competitive subjects performing strength training

The purpose of this study was to assess the precision of the 1-RM prediction equations proposed by Adams (1994), Baechle and Groves (2000), Brzycki (1993), Epley (1985), Lander (1985) and O’Conner et al. (1989) for strength assessment in fitness programs. Thirty one healthy regular strength training male practitioners (mean ± SD: 21.8 ± 4.0 years of age; 75.9 ± 8.4 kg of weight; and 178.1 ± 6.4 cm of height) performed two tests on the bench press exercise: (a) maximum test - determination of the 1-RM load; and (b) submaximum test - determination of the load matching 4 to 10 maximum repetitions. Analysis of variance (ANOVA) found no significant difference (p > .05) between maximum load determination through prediction equations or through the 1-RM test. The coefficient of determination (r2) varied from .94 to .96. The prediction equations had small standard error of estimate (2.7 to 3.2 kg). Results indicate that the 1-RM prediction equations could be used to determine the maximum load at the bench press exercise in subjects with low strength training experience

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

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Search for supersymmetry in final states with jets, missing transverse momentum and one isolated lepton in sqrt{s} = 7 TeV pp collisions using 1 fb-1 of ATLAS data

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