Fluorescence emission spectroscopy was used to investigate interactions between two effectors and BenM, a transcriptional regulator of benzoate catabolism. BenM had a higher affinity for cis,cis-muconate than for benzoate as the sole effector. However, the presence of benzoate increased the apparent dissociation constant (reduced the affinity) of the protein for cis,cis-muconate. Similar result...

This study investigated the effect of a high and low dose of caffeine on antigen-stimulated natural killer (NK) cell (CD3- CD56+) activation after prolonged, strenuous cycling, as assessed by the early-activation molecule CD69. In a randomized crossover design, 12 healthy male endurance-trained cyclists cycled for 90 min at 70% VO2peak 60 min after ingesting either 0 (PLA), 2 (2CAF), or 6 (6CAF...

the aim of this study was to develop an extended-release tablet formulation using a new in situ cross-linking method. the effects of polyvalent cations on theophylline release from tablets made with the polyanionic polymers sodium alginate and sodium carboxymethylcellulose, were investigated. different miliequivalents of the di and tri-valent cation, ca2+ and al3+, were added to tablet formulat...

this paper introduces an innovative partially destructive method, called “twist-off”, for the assessment of in situ concrete strength. in this method a 40mm diameter metal probe is bonded to a concrete surface by means of a high strength epoxy resin adhesive. to measure the concrete compressive strength, a torque is applied using an ordinary torque-meter and the maximum shear stress at failure ...

abstract with increasing population, mine activities for metal proceeding are also increasing, so environment will be influenced by contaminant especially heavy metals. in situ immobilization of heavy metals using inexpensive amendments is considered as a simple and cost-effective approach for reducing heavy metal contamination. in this research we used sequential extraction for assessing reduc...

The photoreceptor photoactive yellow protein (PYP) was used as a model system to study receptor activation and protein folding. Refolding was studied by stopped-flow absorbance spectroscopy for PYP with either a trans or a cis chromophore. Chromophore trans to cis isomerization, the mechanism of light detection by PYP, greatly affects the protein folding process. When the cis chromophore is pre...

background: the excellent biocompatibility, biodegradability and biological properties of the hydrogels, fabricated using natural polymers, especially polysaccharides, are very advantageous for biomedical applications. gum tragacanth (gt) is a heterogeneous highly branched anionic polysaccharide, which has been used extensively in food and pharmaceutical industries. despite,  its desirable prop...