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Plastics have found widespread use in the fields of cosmetic, engineering, and medical sciences due to their wide-ranging mechanical and physical properties, as well as suitability in biomedical applications. However, in the light of the environmental cost of further upscaling current methods of synthesizing many plastics, work has recently focused on the manufacture of these polymers using biological methods (often bacterial fermentation), which brings with them the advantages of both low temperature synthesis and a reduced reliance on potentially toxic and non-eco-friendly compounds. This can be seen as a boon in the biomaterials industry, where there is a need for highly bespoke, biocompatible, processable polymers with unique biological properties, for the regeneration and replacement of a large number of tissue types, following disease. However, barriers still remain to the mass-production of some of these polymers, necessitating new research. This review attempts a critical analysis of the contemporary literature concerning the use of a number of bacteria-derived polymers in the context of biomedical applications, including the biosynthetic pathways and organisms involved, as well as the challenges surrounding their mass production. This review will also consider the unique properties of these bacteria-derived polymers, contributing to bioactivity, including antibacterial properties, oxygen permittivity, and properties pertaining to cell adhesion, proliferation, and differentiation. Finally, the review will select notable examples in literature to indicate future directions, should the aforementioned barriers be addressed, as well as improvements to current bacterial fermentation methods that could help to address these barriers.

The Psychodynamics of Social Networking is part of Karnac’s emergent Psychoanalysis and Popular Culture series (edited by Caroline Bainbridge and Candida Yates). This series aims to explore the rel...

The influence of different feedstuffs on parameters of digestion and ethology in growing rabbits (duration and number of feed intake, needed masticatory movements, pH value in stomach and small intestine, dry matter content of stomach chyme, level of destruction of cell structures in small intestine) was analysed. 384 five weeks old rabbits were fed with one of three feedstuffs: pellets (mean fibre length = 3 mm), fibre blocks (mean fibre length = 40 mm) and hay-oat-beat-ration (length of hay fibre ≥ 70 mm). The masticatory movements and duration for uptake 0.1 g of feedstuffs were measured in a special observation box. Rabbits in group cages were observed by 24 h video recording and duration and numbers of feed intakes were documented. After 8 weeks rabbits were slaughtered and pH values measured in stomach chyme (and dry matter content) and small intestine. Samples of them were taken and histologically examined (total length of villi and crypts, width of villi and degree of destruction determined by scores from 0 [= no destruction] to 3 [= severe destruction of villi]). Pellets lead to a faster feed intake with a lower number of masticatory movements. This equates a minor feeding time per feed intake and a higher amount of feedstuff in a shorter time. The dry matter content in stomach chyme increases and pH value was significantly higher there, but lower in duodenum. They also showed a significantly higher degree of destruction of villi, a shorter length and a larger width of villi than others.

A pilot toxicology database system has been created which is accessible on-line via the world-wide web or in-house via an intranet. It is intended to be suitable as a source of toxicological information and to support structure-activity relationship studies, and it can be searched on chemical structural and substructural as well as toxicological and physico-chemical data. Successful completion of the pilot has led to an ongoing project to develop and expand the system.