background: glioma is the most common primary brain tumor with poor prognosis. temozolomide (tmz) has been used with irradiation (ir) to treat gliomas. the aim of the present study was to evaluate the cytotoxic and radiosensitizing effect of tmz when combined with high-dose and high-dose rate of gamma irradiation in vitro. methods: two ‘u87mg’ cell lines and skin fibroblast were cultured and as...

METHODS. Recombinant human C-crystallin was mixed with various concentrations of glutathione (GSH) and diamide at 25°C for 1 hour. The extent of glutathiolation of the Ccrystallin was determined by mass spectrometry. Native and S-glutathiolated C-crystallins were labeled with I, and proteolytic degradation was determined using both lens fiber lysate and reticulocyte lysate as sources of ubiquit...

This heterogeneous assay for tobramycin involves fluorescein-labeled tobramycin, which competes with native unlabeled tobramycin for anti-tobramycin binding sites. Bound and free labeled antigen are separated by precipitation with a second antibody. Fluorescence intensity of the resuspended precipitate is inversely proportional to native tobramycin concentration. Background interference was con...

A freeze-drying method enabling solubilization of hydrophobic species in aqueous solutions of native hyaluronan is described. The method is based on opening the access to supposed hydrophobic patches on hyaluronan by disturbing its massive hydration shell. Hydrophobic and/or polarity-sensitive fluorescence probes were used as hydrophobic models or indicators of interactions with hydrophobic pat...

The picosecond time-resolved fluorescence decay data of nine single-tryptophan (trp) proteins and two multi-trp proteins in their native and denatured states were analyzed by the maximum entropy method (MEM). In the denatured state (6 M guanidine hydrochloride) a majority of the single-trp proteins show bimodal (at 25 degrees C) and trimodal (at 85 degrees C) distributions with similar patterns...

Binding of native cyt c to L-PG micelles leads to a partially unfolded conformation of cyt c. This micelle-bound state has no stable tertiary structure, but remains as alpha-helical as native cyt c in solution. In contrast, binding of the acid-unfolded cyt c to L-PG micelles induces folding of the polypeptide, resulting in a similar helical state to that originated from the binding of native cy...

High-resolution imaging of molecules intrinsically involved in malignancy and metastasis would be of great value for clinical detection and staging of tumors. We now report in vivo visualization of matrix metalloproteinase activities by MRI and fluorescence of dendrimeric nanoparticles coated with activatable cell penetrating peptides (ACPPs), labeled with Cy5, gadolinium, or both. Uptake of su...

The color is a sensory attribute that influence decisively the judgment of consumers in certain type of food and therefore, the food industries have added dyes to their products. Natural dyes have been demanded by consumers but there are some limitations in its use such as low water solubility and low stability. Therefore, we have sought ways of overcoming these limitations and milk proteins pl...

Insulin has a largely alpha-helical structure and exists as a mixture of hexameric, dimeric, and monomeric states in solution, depending on the conditions: the protein is monomeric in 20% acetic acid. Insulin forms amyloid-like fibrils under a variety of conditions, especially at low pH. In this study we investigated the fibrillation of monomeric human insulin by monitoring changes in CD, atten...

Different spectral probes were employed to study the stabilizing effect of various polyols, such as, ethylene glycol (EG), glycerol (GLY), glucose (GLC) and trehalose (TRE) on the native (N), the acid-denatured (AD) and the thermal-denatured (TD) states of Aspergillus niger glucoamylase (GA). Polyols induced both secondary and tertiary structural changes in the AD state of enzyme as reflected f...