Exploring the impact of metabolic imaging in head and neck cancer treatment.

BACKGROUND: Target volume delineation is performed with anatomical imaging for head and neck cancer. Molecular imaging allows the recognition of specific tumor regions. Its inclusion in the pathway could lead to changes in delineation and resultant treatment plans. METHODS: PRISMA methodology was adhered to when selecting the articles for analysis and only full articles were quality assessed. RESULTS: Seventeen articles were included. Gross tumor volume (GTV) primary, GTV nodal, and other target volumes were evaluated. Positron emission tomography/computerized tomography (PET/CT) produced smaller primary GTVs, although not with diffusion-weighted imaging-magnetic resonance imaging (DWI-MRI) or PET/MRI. The impact of these image modalities on GTV nodal did not display any consistency. Additionally, there was considerable heterogeneity in metrics comparing delineations. Four studies included appraised the dosimetric impact of the changes in target volume delineation. CONCLUSION: Quantifying the impact of molecular imaging is difficult, due to heterogeneity in reporting metrics in molecular imaging modalities and a paucity of detail regarding delineation method and guideline adherence.

Influence of neuromuscular electrical stimulation on the conduction velocity measured using EMG signals provided by linear arrays of electrodes.

Neuromuscular electrical stimulation (NMES) can alter the functioning of muscles and even assist muscle rehabilitation. In this paper, we evaluate the effect of NMES on the conduction velocity (CV) of the brachial biceps' motor units. We used a linear array of electrodes to acquire electromyographic signals, as different subjects perform isometric voluntary contractions (IVCs), with and without prior NMES. Our results show that, after NMES, the CVs at the beginning of the IVCs tend to increase, with respect to the case without NMES. Also, we observed that, while in the absence of NMES, the CVs tend to decrease over time with continued IVCs, this does not happen after 20 minutes of NMES, and the CVs can, in some cases, increase with the contractions.

Oligomerisation and thermal stability of polyvalent integrin alpha5beta1 ligands.

Synthetic oligomeric integrin alpha5beta1 ligands, specifically immobilised to surfaces, facilitate increased fibroblast cell spreading compared with that associated with the monomer. These ligands consist of a N-terminal fibronectin domain pair, a spacer and a di-, tri- or tetrameric coiled coil. However, it is not yet clear what effect fusion of the fibronectin domains has on the predicted oligomerisation of the coiled coils. Using analytical ultracentrifugation we show that the predicted tetrameric and trimeric coiled coils facilitate a corresponding ligand oligomerisation with half-dissociation at 0.7 and 0.2 microM, respectively. In contrast, the predicted dimeric coiled coil formed both dimers and trimers. Under non-reducing conditions, the unique C-terminal thiol-facilitated inter-oligomer dimerisation of the trimeric species, generating hexameric ligands. Disulphide bonding also increased helical stability during thermal unfolding. The work allows the cellular response to these clustered integrin alpha5beta1 ligands to be more accurately interpreted, and has wider implications with respect to the utility of coiled coils as tools to facilitate protein oligomerisation.

IGFBP-3 and IGFBP-5 associate with the cell binding domain (CBD) of fibronectin.

We have used Surface Plasmon Resonance (SPR) - based biosensor technology to investigate the interaction of the six high affinity insulin-like growth factor binding proteins (IGFBP 1-6) with the cell binding domain (CBD) of fibronectin. Using a biotinylated derivative of the ninth and tenth TypeIII domains of FN ((9-10)FNIII), we show that IGFBP-3 and -5 bind to FN-CBD. We show that this binding is inhibited by IGF-I and that, for IGFBP-5, binding occurs through the C-terminal heparin binding domain of the protein. Using site-directed mutagenesis of (9-10)FNIII, we show both the "synergy" and RGD sites within these FN domains are required for maximum binding of both IGFBPs. We discuss the possible biological consequences of our results.