In Salmonella typhimurium and Escherichia coli, the hemA gene encodes the enzyme glutamyl-tRNA reductase, which catalyzes the first committed step in heme biosynthesis. We report that when heme limitation is imposed on cultures of S. typhimurium, glutamyl-tRNA reductase (HemA) enzyme activity is increased 10- to 25-fold. Heme limitation was achieved by a complete starvation for heme in hemB, he...

Polyhydroxyethylmethacrylate polymers (poly-HEMA) form hydrogels that provide an excellent alternative to agar in the production of salt bridges for use in bioelectrochemical experiments. A method for the simple production of poly-HEMA salt bridges is described. The poly-HEMA bridges were compared with agar bridges of similar geometry. Whereas poly-HEMA salt bridges have a conductivity that is ...

The Escherichia coli hemA gene, essential for the synthesis of 5-aminolevulinic acid (ALA), was isolated and sequenced. The following criteria identified the cloned gene as hemA. (i) The gene complemented a hemA mutation of E. coli. (ii) The gene was localized to approximately 26.7 min on the E. coli chromosomal linkage map, consistent with the location of the mapped hemA locus. Furthermore, DN...

The water-soluble HEMA has polar properties with small dimension to enhance the wetting properties of the adhesive solution and the penetration efficacy of the adhesive into demineralized dentin [3]. HEMA has been reported to be positively influence bond strength to dentin. Because of its hydrophilic character, it is also frequently added to improve miscibility of hydrophobic and hydrophilic co...

Poly(2-hydroxyethyl methacrylate) p(HEMA) is a biocompatible polymer that forms a hydrogel when mixed with water. Water content and oxygen permeability, mechanical properties of p(HEMA) hydrogel can be controlled by cross-linking rate or by copolymerization; that is why p(HEMA) hydrogels have multiple biomedical applications. This paper objective was to analyse a biomaterial made of p(HEMA) for...

We report the fabrication of carbohydrate microarrays on a photoactive polymer, poly(HEMA-co-HEMA-PFPA), synthesized by RAFT copolymerization of 2-hydroxyethyl methacrylate (HEMA) and perfluorophenyl azide (PFPA)-derivatized HEMA (HEMA-PFPA). PFPA allows the covalent immobilization of carbohydrates whereas the HEMA polymer provides an antifouling surface, thus the microarrays can be used direct...

Hydrogels described herein were developed as anti-microbial coating materials. Three different hydrogels, p(HEMA), p(85%HEMA-co-15% MMA), and p(85% HEMA-co-15% MAA) loaded with two cationic surfactants, BAK, DDAB, respectively. DDAB owned better effectivity than BAK in killing S. aureus E. coli. Compared to unmodified(HEMA), all drug-loaded samples exhibited significant anti-adherence ability a...

Swelling pressure measurements were performed on degrading dextran hydroxyethyl methacrylate (dex-HEMA) hydrogels. In these networks, the cross-links are hydrolyzable carbonate ester bonds formed between methacrylate groups and dextran molecules. It is demonstrated that dex-HEMA gels made in the presence of a known amount of free dextran chains exhibit osmotic properties similar to those of par...

BACKGROUND AND PURPOSE We investigated the use of 2-poly-hydroxyethyl-methacrylate (2-P-HEMA) as an embolic agent in swine arteriovenous malformations (AVMs). METHODS In seven mini swine, experimental AVMs were created surgically. The aim of treatment was complete embolization of the nidus compartment filled by the feeding artery, without brain embolization. Six animals received pure liquid 2...

The purpose of this study was to determine the influence of incrementally added uncured HEMA in experimental HEMA-added glass ionomer cement (HAGICs) on the mechanical and shear bond strength (SBS) of these materials. Increasing contents of uncured HEMA (10-50 wt.%) were added to a commercial glass ionomer cement liquid (Fuji II, GC, Japan), and the compressive and diametral tensile strengths o...