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We sought to explore the utility of the verification trial to confirm individual attainment of 'true' VO2max in altitude-residing, endurance-trained runners during treadmill exercise. 24 elite endurance-trained men and women runners (age = 21.5±3.3yr, ht-174.8±9.3cm, body mass = 60.5±6.7 kg, PR 800 m 127.5 ±13.1 s) completed a graded exercise test (GXT) trial (VO2max = 60.C±5.8mL⋅ kg-11⋅min-1), and returned 20min after incremental exercise to complete a verification trial (VO2max = 59.6±5.7mL⋅kg-1⋅ min-1) of constant load, supramaximal exercise. The incidence of 'true' V02max confirmation using the verification trial was 24/24 (100%) with all participants revealing differences in VO2max ≤3% (the technical error of our equipment) between the GXT and verification trials. These findings support use of the verification trial to confirm VO2 max attainment in altitude-residing, endurance-trained runners. [ABSTRACT FROM AUTHOR]

We sought to explore the utility of the verification trial to confirm individual attainment of 'true' VO2max in altitude-residing, endurance-trained runners during treadmill exercise. 24 elite endurance-trained men and women runners (age=21.5±3.3 yr, ht=174.8±9.3 cm, body mass=60.5±6.7 kg, PR 800 m 127.5±13.1 s) completed a graded exercise test (GXT) trial (VO2max=60.0±5.8 mL·kg(-1)·min(-1)), and returned 20 min after incremental exercise to complete a verification trial (VO2max=59.6±5.7 mL·kg(-1)·min(-1)) of constant load, supramaximal exercise. The incidence of 'true' VO2max confirmation using the verification trial was 24/24 (100%) with all participants revealing differences in VO2max≤3% (the technical error of our equipment) between the GXT and verification trials. These findings support use of the verification trial to confirm VO2max attainment in altitude-residing, endurance-trained runners., (© Georg Thieme Verlag KG Stuttgart · New York.)

We report the functional characterization of BipA, a GTPase that undergoes tyrosine phosphorylation in an enteropathogenic Escherichia coli (EPEC) strain. BipA mutants adhere to cultured epithelial cells but fail to trigger the characteristic cytoskeletal rearrangements found in cells infected with wild-type EPEC. In contrast, increased expression of BipA enhances actin remodelling and results in the hyperformation of pseudopods. BipA appears to be the first example of a new class of virulence regulator, as it also controls flagella-mediated cell motility and resistance to the antibacterial effects of a human host defence protein. Its striking sequence similarity to ribosome-binding elongation factors suggests that it uses a novel mechanism to modulate gene expression.

Sephadex G-200 gel filtration of DNA cellulose-treated crude extracts of rat skeletal muscle, revealed a broad peak-fraction of tRNA-inhibitory protein kinases (PK) coeluted endogenous substrates. In comparison, the elution profile of baker's yeast exhibited multiple peak-fractions of tRNA-inhibiting PK. Various tRNA all showed inhibition to PK. In the presence of regulatory subunit of cyclic AMP-dependent protein kinase, tRNA did not exert synergetic inhibition on PK. Moreover, the interaction of tRNA with active muscle PK fractions could not be monitored by the increment of absorbance at 340 nm. tRNA had no significant regulatory effect on the phosphorylation of actin and myosin.

Binding (or interaction) of cortisol with microbial molecule(s) was observed by employing Bio-Gel HTP affinity chromatography and subsequently by fluorescence spectrophotometry. Molecule(s) in the crude extract of baker's yeast and in other microbial proteases exhibited varied degrees of cortisol-binding. Bacterial protease (type IX) had highest, while the type XXVI enzyme had the lowest, binding capacity. In addition, these two proteases exhibited a distinct difference in the alterations of ultraviolet spectra due to interaction with cortisol. Using casein as a substrate, cortisol, CTP, trypsin inhibitor or leupeptin appreciably inhibited type IX protease at low concentrations of Ca2+. However, thyroxine had no effect on this protease.