scholarly journals Impact of soft protein interactions on the excretion, extent of receptor occupancy and tumor accumulation of ultrasmall metal nanoparticles: a compartmental model simulation

RSC Advances ◽  
2019 ◽  
Vol 9 (46) ◽  
pp. 26927-26941 ◽  
Author(s):  
Alioscka A. Sousa
Keyword(s):  
Metal Nanoparticles ◽  
Protein Interactions ◽  
Plasma Proteins ◽  
Compartmental Model ◽  
Model Simulation ◽  
Receptor Occupancy ◽  
Tumor Pharmacokinetics ◽  
Tumor Accumulation ◽  
Soft Interactions

A compartmental model simulation shows that the blood and tumor pharmacokinetics of ultrasmall metal nanoparticles can be modulated by soft interactions with plasma proteins.

Factors contributing to high levels of plasma iodide in brook trout, Salvelinus fontinalis (Mitchill)

1975 ◽  
Vol 53 (3) ◽  
pp. 267-277 ◽  
Author(s):  
Linda A. Gregory ◽  
J. G. Eales
Keyword(s):  
Protein Interactions ◽  
Brook Trout ◽  
Plasma Proteins ◽  
Iodine Concentration ◽  
High Plasma ◽  
Natural Food ◽  
Storage Site ◽  
Tissue Storage ◽  
Commercial Diet ◽  
Protein Levels

The influences of dietary iodine, ambient iodide, tissue storage of iodide, and iodide binding to plasma proteins have been related to the high plasma iodide in laboratory brook trout.Plasma iodide exceeded 1800 μg/100 ml (μg%) for trout acclimated at 13 °C and fed an Ewos commercial diet. This was largely due to (i) efficient iodide absorption from the gut, and (ii) an iodine concentration in Ewos food (31–35 μg I/g dry wt.) that was 20–78 times greater than that of four other artificial foods or that of several natural food items.Ambient iodide ranged seasonally from 1.26 to2.21 μg I/liter. This source probably contributed little to the high plasma iodide, but helped to maintain plasma levels during starvation or use of low-iodide diets.No major extrathyroidal iodide storage site was found in 15 organs or tissues examined.Iodide binds to brook trout plasma proteins, but the concentration of binding sites is less than that reported for other species. This binding aids maintenance of plasma iodide, particularly when iodide intake is low. Variation in plasma iodide between individual fish was not clearly related to variations in iodide–protein interactions nor to variations in plasma protein levels.

Using Rheology to Probe the Mechanism of Joint Lubrication: Polyelectrolyte/protein interactions in Synovial Fluid

2001 ◽  
Vol 711 ◽  
Author(s):  
Katherine M. N. Oates ◽  
Wendy E. Krause ◽  
Ralph H. Colby
Keyword(s):  
Hyaluronic Acid ◽  
Synovial Fluid ◽  
Protein Interactions ◽  
Plasma Proteins ◽  
Fluid Model ◽  
Structural Features ◽  
Protein Solutions ◽  
Shear Rates ◽  
Strong Shear ◽  
Γ Globulins

ABSTRACTThe outstanding lubricating properties of synovial fluid, found in freely moving mammalian joints, may be due to intermolecular associations between hyaluronic acid, an anionic polysaccharide, and the plasma proteins. A synovial fluid model comprised of hyaluronic acid and the plasma proteins albumin and γ-globulins, was constructed. Rheological measurements reveal a pronounced viscoelasticity with a strong shear history dependence for the synovial fluid model and the plasma protein solutions at low shear rates. The addition of the anti-inflammatory drug D-Penicillamine to the solution alters the rheology of the synovial fluid model. We present two ideas about the structural features of synovial fluid that may explain this viscoelasticity and suggest further experimental techniques that can be used to test these ideas.

scholarly journals Nanoparticle-protein interactions: from crucial plasma proteins to key enzymes

2011 ◽  
Vol 304 ◽  
pp. 012039 ◽  
Author(s):  
Elodie Sanfins ◽  
Julien Dairou ◽  
Fernando Rodrigues-Lima ◽  
Jean-Marie Dupret
Keyword(s):  
Protein Interactions ◽  
Plasma Proteins ◽  
Key Enzymes

Plasma thermogram profiling: A novel biomarker for lung cancer

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e22074-e22074 ◽  
Author(s):  
D. Xiang ◽  
N. C. Garbett ◽  
J. Chaires ◽  
D. L. Laber ◽  
G. H. Kloecker
Keyword(s):  
Lung Cancer ◽  
Healthy Volunteers ◽  
Protein Interactions ◽  
Plasma Proteins ◽  
Molecular Mechanisms ◽  
Plasma Proteome ◽  
Protein Protein Interactions ◽  
Scanning Calorimetry ◽  
Novel Approach ◽  
The Individual

e22074 Background: Currently, there are no clinically useful biomarkers for lung cancer (LC). We developed a novel approach by using differential scanning calorimetry (DSC) to analyze the plasma proteome of LC patients. Our assay produces a signature snapshot of the plasma proteome based on the thermal properties of the constituent proteins within the mixture. Each individual protein has a unique and characteristic melting temperature and melting enthalpy. These biophysical properties are as intrinsic and unique for each protein as are its sequence, mass, and charge. The denaturation of plasma results in a composite signature thermogram that represents the sum of all of the individual proteins within the proteome, weighted according to their concentration within the plasma or serum. Our goal is to identify unique thermogram profiles as biomarkers for lung cancer evaluation. Methods: Plasma samples were collected from LC patients and healthy volunteers. Sample analysis was performed using an automated capillary DSC. Comparison of plasma thermograms from controls and diseased individuals was done using quantile-quantile plots and the Kolmogorov-Smirnov test. Results: One hundred samples were obtained from healthy volunteers. DSC thermograms from control plasma were highly reproducible and yielded a characteristic signature with a well-defined shape and temperature maxima. Twenty samples from LC patients were obtained at diagnosis. Plasma from LC individuals yielded a unique thermogram that differs from that of healthy controls. Preliminary results suggested that DSC was sensitive to properties of the plasma proteins other than their charge and mass. We hypothesize that changes in thermogram shapes and positions in LC can arise from changes in the concentrations of plasma proteins, from disease-induced protein-protein interactions, or from the secretion into plasma of disease-related peptides that can bind to the most abundant plasma proteins. Conclusions: Lung cancer may have a characteristic signature thermogram that may serve as a biomarker for LC; further studies are needed to elucidate the biophysical and molecular mechanisms of different thermograms between normal individuals versus those with disease or cancer. No significant financial relationships to disclose.

scholarly journals Chemotaxis to cAMP and slug migration in Dictyostelium both depend on migA, a BTB protein.

1997 ◽  
Vol 8 (9) ◽  
pp. 1763-1775 ◽  
Author(s):  
R Escalante ◽  
D Wessels ◽  
D R Soll ◽  
W F Loomis
Keyword(s):  
Mutant Strain ◽  
Restriction Enzyme ◽  
Protein Interactions ◽  
Actin Polymerization ◽  
Genetic Defect ◽  
Regulatory Region ◽  
Receptor Occupancy ◽  
Full Length ◽  
Developmental Defects ◽  
Chemical Gradients

Chemotaxis in natural aggregation territories and in a chamber with an imposed gradient of cyclic AMP (cAMP) was found to be defective in a mutant strain of Dictyostelium discoideum that forms slugs unable to migrate. This strain was selected from a population of cells mutagenized by random insertion of plasmids facilitated by introduction of restriction enzyme (a method termed restriction enzyme-mediated integration). We picked this strain because it formed small misshapen fruiting bodies. After isolation of portions of the gene as regions flanking the inserted plasmid, we were able to regenerate the original genetic defect in a fresh host and show that it is responsible for the developmental defects. Transformation of this recapitulated mutant strain with a construct carrying the full-length migA gene and its upstream regulatory region rescued the defects. The sequence of the full-length gene revealed that it encodes a novel protein with a BTB domain near the N terminus that may be involved in protein-protein interactions. The migA gene is expressed at low levels in all cells during aggregation and then appears to be restricted to prestalk cells as a consequence of rapid turnover in prespore cells. Although migA- cells have a dramatically reduced chemotactic index to cAMP and an abnormal pattern of aggregation in natural waves of cAMP, they are completely normal in size, shape, and ability to translocate in the absence of any chemotactic signal. They respond behaviorally to the rapid addition of high levels of cAMP in a manner indicative of intact circuitry connecting receptor occupancy to restructuring of the cytoskeleton. Actin polymerization in response to cAMP is also normal in the mutant cells. The defects at both the aggregation and slug stage are cell autonomous. The MigA protein therefore is necessary for efficiently assessing chemical gradients, and its absence results in defective chemotaxis and slug migration.

A Compartmental Model for Supercritical Coal-Fired Boiler Systems

2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Longzhou Qi ◽  
Shuhong Huang ◽  
Yanping Zhang ◽  
Xing Xu ◽  
Yu Li ◽  
...  
Keyword(s):  
Compartmental Model ◽  
Model Simulation ◽  
Control Strategies ◽  
Operating Conditions ◽  
Parameter Method ◽  
Lumped Parameter ◽  
Proposed Model ◽  
Simulation Results ◽  
Model Features ◽  
Lumped Parameter Method

A compartmental furnace model for supercritical coal-fired boiler systems is presented in this paper. Instead of the traditional lumped parameter method, the furnace is divided to seven compartments along the height based on the positions of the burner groups. The lower six compartments correspond to the six groups of burners, respectively. This model provides the possibility to connect the pulverization system and the furnace, the variability of the combustion property caused by changes of the pulverization system can be studied by switching the operating conditions. To evaluate the proposed model, simulation results are compared with available data from a 600 MW supercritical coal-fired boiler and reasonably good agreement is achieved. The simulation results also show that the compartmental model features a better precision than the lumped parameter modeling. This model allows for evaluating different control strategies and subsequently proposing optimization strategies for boiler system operation.

Plasma protein-mediated transport of steroid and thyroid hormones

1987 ◽  
Vol 252 (2) ◽  
pp. E157-E164 ◽  
Author(s):  
W. M. Pardridge
Keyword(s):  
Plasma Protein ◽  
Conformational Changes ◽  
Plasma Proteins ◽  
Receptor Occupancy ◽  
Large Reservoir ◽  
In Vitro Measurements ◽  
Drug Receptor ◽  
Plasma Compartment

The free hormone or free drug hypotheses have traditionally assumed that the concentration of cellular exchangeable hormone (i.e., the pool that drives cellular hormone or drug receptor occupancy) can be reliably estimated by in vitro measurements of unbound hormone concentrations. The corollary of this view is that the large reservoir of bound hormone in blood is passively transported by plasma proteins and is physiologically inactive. However, when these assumptions are subjected to direct empiric testing with either in vivo or perfused organ techniques, it is found that the large pool of bound hormone in blood is operationally available for transport across microcirculatory barriers without the plasma protein, per se, significantly exiting the plasma compartment. This process is believed to involve a mechanism of enhanced dissociation of hormone or drug from the plasma protein caused by transient conformational changes about the ligand binding site within the microcirculation: The biochemical mechanism of the interaction of the plasma protein with the surface of the microcirculation may involve receptor, charged selectivity, or local inhibitor mechanisms.

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