Arginine-glycine-aspartic acid functional branched semi-interpenetrating hydrogels.

For the first time a series of functional hydrogels based on semi-interpenetrating networks with both branched and crosslinked polymer components have been prepared and we show the successful use of these materials as substrates for cell culture. The materials consist of highly branched poly(N-isopropyl acrylamide)s with peptide functionalised end groups in a continuous phase of crosslinked poly(vinyl pyrrolidone). Functionalisation of the end groups of the branched polymer component with the GRGDS peptide produces a hydrogel that supports cell adhesion and proliferation.

Nerve guides manufactured from photocurable polymers to aid peripheral nerve repair.

The peripheral nervous system has a limited innate capacity for self-repair following injury, and surgical intervention is often required. For injuries greater than a few millimeters autografting is standard practice although it is associated with donor site morbidity and is limited in its availability. Because of this, nerve guidance conduits (NGCs) can be viewed as an advantageous alternative, but currently have limited efficacy for short and large injury gaps in comparison to autograft.

Macrostructuring of emulsion-templated porous polymers by 3D laser patterning.

Micro-stereolithography (μSL) is used to produce 3D porous polymer structures by templating high internal phase emulsions. A variety of structures are produced, including lines, squares, grids, and tubes. The porosity matches that of materials produced by conventional photopolymerization.

Retrograde transport of toxins across the endoplasmic reticulum membrane.

Several protein toxins, including the A chain of the plant protein ricin (RTA), enter mammalian cells by endocytosis and catalytically modify cellular components to disrupt essential cellular processes. In the case of ricin, the process inhibited is protein synthesis. In order to reach their cytosolic substrates, several toxins undergo retrograde transport to the ER (endoplasmic reticulum) before translocating across the ER membrane.

Ricin. Mechanisms of cytotoxicity.

Ricin is a heterodimeric protein produced in the seeds of the castor oil plant (Ricinus communis). It is exquisitely potent to mammalian cells, being able to fatally disrupt protein synthesis by attacking the Achilles heel of the ribosome. For this enzyme to reach its substrate, it must not only negotiate the endomembrane system but it must also cross an internal membrane and avoid complete degradation without compromising its activity in any way.

Gene disruption in Schizosaccharomyces pombe using a temperature-sensitive Ura4p.

We have generated a temperature-sensitive form of the Ura4p protein from the fission yeast Schizosaccharomyces pombe. A single T-to-C mutation at nucleotide 782 (relative to the initiator ATG codon of ura4) changes the leucine residue at position 261 in Ura4p to a proline. The mutant Ura4p(ts) supports growth at 30 degrees C but is unable to allow growth at 37 degrees C in the absence of uracil when a single copy of the gene is integrated into the host chromosome.

Initial training as a stimulus for optimal physical fitness in firemen.

In this investigation the physical fitness of 34 recruits to the UK Fire Service was assessed before and after their initial training (tests 1-2) and on three occasions (tests 3-5) during the first 18 months of their service (n = 34 + 6 = 40). The initial training (test 2-test 1) resulted in an increase in maximum aerobic power (11% p < 0.05), body mass (2 kg, p < 0.