Novel CD3Z and CD3E Deficiency in Two Unrelated Females

Journal of Clinical Immunology -     

Environmentally responsive peptides as anticancer drug carriers

The tumor microenvironment provides multiple cues that may be exploited to improve the efficacy of established chemotherapeutics; furthermore, polypeptides are uniquely situated to capitalize on these signals. Peptides provide: 1) a rich repertoire of biologically specific interactions to draw upon; 2) environmentally responsive phase behaviors, which may be tuned to respond to signatures of disease; 3) opportunities to direct self-assembly; 4) control over routes of biodegradation; 5) the option to seamlessly combine functionalities into a single polymer via a one-step biosynthesis. As development of cancer-targeted nanocarriers expands, peptides provide a unique source of functional units that may target disease. This review explores potential microenvironmental physiology indicative of tumors and peptides that have demonstrated an ability to target and deliver to these signals.     

The stability of nonporous and macroporous titania thin films in aqueous electrolyte solutions

A simple electrochemical approach was used to evaluate the stability and porosity of titania and silica thin films spin coated on electrode surfaces. This approach involved monitoring the magnitude of the Faradaic current of diffusing redox probes at the modified electrode surfaces over the course of a week to 4.5 months. Relatively nonporous films were examined as well as films templated with polystyrene latex spheres. The results show that templated titania films were significantly more porous compared to non-templated films. After the defect sites in the templated films were blocked, their long-term stability in aqueous electrolyte was evaluated. For titania, blocking was done by spin coating a dilute titania sol on the top of the film whereas for silica, the film was soaked in octyltrimethoxysilane. Both types of titania films (templated and non-templated) were found to be significantly more stable than the corresponding silica films, showing no signs of deterioration in simple electrolyte solutions during the entire evaluation period. In contrast, silica films showed significant deterioration in as little as 3 days. The enhanced stability of the titania films relative to silica films in near neutral electrolyte solutions was attributed to the differences in the point of zero charge of the oxide films.     

Numerical simulation of mechanical mitral heart valve closure

A computational fluid dynamic simulation of a mechanical heart valve closing dynamics in the mitral position was performed in order to delineate the fluid induced stresses in the closing phase. The pressure and shear stress fields in the clearance region and near the inflow (atrial) side of the valve were computed during the mitral heart valve closure. Three separate numerical simulations were performed. The atrial chamber pressure was assumed to be zero in all the simulations. The first simulation was steady flow through a closed mitral valve with a ventricular pressure of 100 mm Hg (1.3 kPa). In the second simulation, the leaflet remained in the closed position while the ventricular pressure increased from 0 to 100 mm Hg at a rate of 2000 mm Hg/s (simulating leaflet closure by gravity before the ventricular pressure rise – gravity closure). In the third case, the leaflet motion from the fully open position to the fully closed position was simulated for the same ventricular pressure rise (simulating the normal closure of the mechanical valve). Normal closure (including leaflet motion towards closure, and sudden stop in the closed position) resulted in a relatively large negative pressure transient which was not present in the gravity closure simulation. The wall shear stresses near the housing and the leaflet edge close to the inflow side were around 4000 Pa with normal closure compared to about 725 Pa with gravity closure. The large negative pressure transients and significant increase in wall shear stresses due to the simulation of normal closure of the mechanical valve is consistent with the previously reported increased blood damage during the closing phase. © 2001 Biomedical Engineering Society. PAC01: 8719Hh, 8780-y, 8719Uv, 8710+e     

Identification and functional expression of the Arabidopsis thaliana vacuolar glucose transporter 1 and its role in seed germination and flowering

Sugar compartmentation into vacuoles of higher plants is a very important physiological process, providing extra space for transient and long-term sugar storage and contributing to the osmoregulation of cell turgor and shape. Despite the long-standing knowledge of this subcellular sugar partitioning, the proteins responsible for these transport steps have remained unknown. We have identified a gene family in Arabidopsis consisting of three members homologous to known sugar transporters. One member of this family, Arabidopsis thaliana vacuolar glucose transporter 1 (AtVGT1), was localized to the vacuolar membrane. Moreover, we provide evidence for transport activity of a tonoplast sugar transporter based on its functional expression in bakers' yeast and uptake studies in isolated yeast vacuoles. Analyses of Atvgt1 mutant lines indicate an important function of this vacuolar glucose transporter during developmental processes like seed germination and flowering.