A series of tri[(p-carboranylmethylthio)tetrafluorophenyl]porphyrin conjugates of linear and branched polyamines, glucose, arginine, tri(ethylene glycol), and Tyr-D-Arg-Phe-β-Ala (YRFA) peptide were synthesized. These conjugates were investigated for their BBB permeability in human hCMEC/D3 brain endothelial cells, and their cytotoxicity and uptake were assessed using human glioma T98G cells. F...

Solubility and permeability of gases in glassy polymers have been considered with the aim of illustrating the applicability of thermodynamically-based models for their description and prediction. The solubility isotherms are described by using the nonequilibrium lattice fluid (NELF) (model, already known to be appropriate for nonequilibrium glassy polymers, while the permeability isotherms are ...

Electrical measurements were carried out to investigate the contribution of chloroplast lipids to the passive proton permeability of both the thylakoid and inner-envelope membranes. Permeability coefficient and conductance to protons were measured for solvent-free bilayers made from monogalactosyldiglyceride:digalactosyldiglycerid: sulfoquinovosyldiglyceride:phosphatidylglycerol (2:1:0.5:0.5, w...

BACKGROUND AND PURPOSE Cardiac arrest and resuscitation in immature piglets result in a delayed increase in blood-brain barrier permeability. We tested the hypothesis that pretreatment with oxygen radical scavengers reduces postischemic permeability. METHODS Permeability was assessed by measuring the plasma-to-brain transfer coefficient of the small amino acid, alpha-aminoisobutyric acid, in ...

Cement substitution in self compacting concrete (SCC) is emphasized to conserve environment, reduce cost and utilize waste materials. This paper focuses on comparing the permeability and drying shrinkage of SCC containing Wollastonite micro fiber (WMF), a cheap pozzolanic fiber with respect to flyash. Microsilica was added for providing required viscosity to maintain homogeneity of the mixes. T...

LIST OF PRINCIPAL SYMBOLS Ey Hz H h k ^-component of electric field strength, z-component of magnetic field strength. Height of aperture. Height of source slot above guiding surface. Phase constant for free space. kx = Decay constant of surface wave. V(h) = Voltage across slot at height h. x,y,z = Rectangular co-ordinates. Phase-change coefficient in ^-direction. Phase-change coefficient of sur...

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is widely used to evaluate tumor permeability, yet measurements have not been directly validated in brain tumors. Our purpose was to compare estimates of forward leakage K(trans) derived from DCE-MRI to the estimates K obtained using [(14)C]aminoisobutyric acid quantitative autoradiography ([(14)C]AIB QAR), an established method of ...

The water permeability of isolated toad ovarian oocytes was found from their rate of shrinkage in hypertonic Ringer's solution. Apparent membrane permeability coefficients, (k), calculated on the assumption that the cell surface was smooth, rose from about 20 fim s" in small cells 200 /im in diameter, to 35 fim s' in cells 800 fim in diameter and then fell to 5 fim s' in large cells of 2000 fim...

In this article we compare solutions to elliptic problems having rapidly oscillated conductivity (permeability, etc) coefficient with solutions to corresponding homogenized problems obtained from two-scale extensions of the initial coefficient. The comparison is done numerically on several one and two dimensional test problems with randomly generated coefficients for different intensities of os...

A slit-lamp fluorophotometric method is presented that permits calculation of a blood-retinal barrier permeability to fluorescein (P) and a diffusion coefficient for fluorescein in the vitreous body (D). The calculations are performed by relating the time course of the free--not protein bound--fluorescein concentration in the bloodstream with the fluorescein concentration profile in the vitreou...