BACKGROUND Polyethylenimine (PEI)-based nonviral gene-delivery systems are commonly employed because of their high transfection efficiency. However, the toxic nature of PEI is a significant obstacle in clinical gene therapy. In this study, we developed biocompatible glycerol triacrylate-spermine (GT-SPE) polyspermine as a nanosized gene carrier for potential lung cancer gene therapy. METHODS ...

The application of conventional solid polymer electrolyte (SPE) to lithium-oxygen (Li-O2) batteries has suffered from a limited active reaction zone due to thick SPE and subsequent lack of O2 gas diffusion route in the positive electrode. Here we present a new design for a three-dimensional (3-D) SPE structure, incorporating a carbon nanotube (CNT) electrode, adapted for a gas-based energy stor...

The paternal-effect embryonic-lethal gene, spe-11, is required for normal development of early C. elegans embryos. Spe-11 embryos fail to complete meiosis, form a weak eggshell, fail to orient properly the first mitotic spindle, and fail to undergo cytokinesis. Here we report cloning and sequencing of the spe-11 gene, which encodes a novel protein. As predicted by the paternal-effect mutant phe...

Streptococcal pyrogenic exotoxin B (SPE B), a cysteine protease, is an important virulence factor in group A streptococcal (GAS) infection. SPE B binds and cleaves antibody isotypes and further impairs the immune system by inhibiting complement activation. In this study, we examined the antibody-binding site of SPE B and used it to block SPE B actions during GAS infection. We constructed differ...

During Caenorhabditis elegans spermatogenesis, asymmetric partitioning of cellular components principally occurs via ER/Golgi-derived organelles, named fibrous body-membranous organelles. In C. elegans spe-4 mutants, morphogenesis of fibrous body-membranous organelle complexes is defective and spermatogenesis arrests at an unusual cellular stage with four haploid nuclei within a common cytoplas...

We have previously identified integrin alpha(v)beta(3) and Fas as receptors for the streptococcal pyrogenic exotoxin B (SPE B), and G308S, a mutant of SPE B that binds to Fas only. In the current study we found that after binding to alpha(v)beta(3), SPE B stimulated the tyrosine phosphorylation of JAK2 and STAT1. STAT1 tyrosine phosphorylation was inhibited by a JAK2 inhibitor, AG490, short int...

Because of the association of the group A streptococcal pyrogenic exotoxins (SPEs) with erythrogenic toxin used in the classical Dick test, the involvement of the SPEs in production of erythematous skin reactions was assessed. Unless they had been presensitized, young adult rabbits failed to show skin reactions after intracutaneous challenged with SPEs. Rabbits presensitized to purified protein...

The cocrystal structure of streptococcal pyrogenic exotoxin C (SPE C) with HLA-DR2a (DRA*0101,DRB5*0101) revealed a zinc-dependent interaction site through residues 167, 201, and 203 on SPE C and residue 81 on the beta-chain of HLA-DR2a (DRA*0101,DRB5*0101). Mutation of these SPE C residues resulted in dramatically reduced biological activities. Thus, the zinc-dependent major histocompatibility...

This paper summarizes the development of a methodology for the restimulation candidate selection in tight gas sands. The methodology incorporates virtual intelligence techniques (artificial neural networks, genetic algorithms and fuzzy logic) to achieve this objective. Artificial neural networks are used to develop a representative model of the completion and hydraulic fracturing process in a s...