Human serum albumin (HSA) is the most abundant protein in the blood plasma. Drug binding to HSA is crucial to study the absorption, distribution, metabolism, efficiency and bioavailability of drug molecules. In this study, isothermal titration calorimetry and molecular dynamics simulation of HSA and its complex with indometacin (IM) were performed to investigate thermodynamics parameters and th...

introduction: the major histocompatibility complex (mhc) is a group of cell surface proteins that are essential for recognizing foreign molecules in human and other mammals. the physiologic function of mhc molecules is the presentation of peptides to t cells. in this study, we evaluated the purification of a class ii mhc molecule (hla-dr) from a human burkitt′s lymphoma cell line; daudi. materi...

Tris(vancomycin carboxamide) binds a trivalent ligand derived from D-Ala-D-Ala with very high affinity: dissociation constant (Kd) approximately 4 x 10(-17) +/- 1 x 10(-17) M. High-affinity trivalent binding and monovalent binding are fundamentally different. In trivalent (and more generally, polyvalent) binding, dissociation occurs in stages, and its rate can be accelerated by monovalent ligan...

Xenon and radon have many similar properties, a difference being that all 35 isotopes of radon ((195)Rn-(229)Rn) are radioactive. Radon is a pervasive indoor air pollutant believed to cause significant incidence of lung cancer in many geographic regions, yet radon affinity for a discrete molecular species has never been determined. By comparison, the chemistry of xenon has been widely studied a...

Caffeine consumption causes significant physiologic effects due to its antagonism of adenosine receptors. The Al adenosine receptor is coupled in an inhibitory manner to adenylate cyclase. To study the effects of chronic caffeine ingestion, rats were provided with 0.1% caffeine drinking solution for 28 d. The Al adenosine receptor agonist radioligand [3Hjphenylisopropyladenosine identifies two ...

The kinetic basis for the reduction in the oxygen affinity of hemoglobin due to carbon dioxide at constant pH, is studied by measuring the deoxygenation rates of oxyhemoglobin with dithionite, as well as the rate of binding of carbon monoxide to deoxyhemoglobin. These studies were performed in buffer containing 0.05 M potassium phosphate, as well as various mixtures of potassium chloride and po...

The present study was undertaken to study the binding of several thyroid hormones and structurally related compounds to human serum thyroxine-binding alpha-globulin (TBG). The source of TBG was normal human serum diluted 1:100 in 0.035 M barbital buffer, pH 7.4. In the binding assays, 125I-thyroxine, unlabeled thyroxine, and diluted serum were incubated for 20 h at 37 degrees in Plexiglas equil...

Binding of insulin to islets of Langerhans was studied. It was found that "specific" binding of [125I]insulin ("specific" binding equals total binding minus nonspecific binding) was saturable with respect to time and insulin concentration and depended on the number of incubated islets. Furthermore, bound insulin was displaced by native insulin in a dose-dependent manner. Bound [125I]insulin was...

[3H]Kainic acid binding sites with a slow dissociation rate in the rat limbic system were investigated in detail. Extensively washed membranes prepared from the hippocampal formation and from the region comprising the amygdala and the piriform cortex yielded non-linear Scatchard plots. Microdissection showed that the high-affinity component (affinity constant around 1 nM) was present in the hip...

Brain-derived neurotrophic factor (BDNF), a protein known to support the survival of embryonic sensory neurons and retinal ganglion cells, was derivatized with 125I-Bolton-Hunter reagent and obtained in a biologically active, radioactive form (125I-BDNF). Using dorsal root ganglion neurons from chick embryos at 9 d of development, the basic physicochemical parameters of the binding of 125I-BDNF...