Comparison of cell wall proteins of Saccharomyces cerevisiae as anchors for cell surface expression of heterologous proteins.

The carboxyl-terminal regions of five cell wall proteins (Cwp1p, Cwp2p, Ag alpha 1p, Tip1p, and Flo1p) and three potential cell wall proteins (Sed1p, YCR89w, and Tir1p) all proved capable of immobilizing alpha-galactosidase in the cell wall of Saccharomyces cerevisiae. The fraction of the total amount of fusion protein that was localized to the cell wall varied depending on the anchor domain used. The highest proportion of cell wall incorporation was achieved with Cwp2p, Ag alpha 1p, or Sed1p as an anchor. Although 80% of these fusion proteins were incorporated in the cell wall, the total production of alpha-galactosidase-Ag alpha 1p was sixfold lower than that of alpha-galactosidase-Cwp2p and eightfold lower than that of alpha-galactosidase-Sed1p. Differences in mRNA levels were not responsible for this discrepancy, nor was an intracellular accumulation of alpha-galactosidase-Ag alpha 1p detectable. A lower translation efficiency of the alpha-galactosidase-AG alpha 1 fusion construct is most likely to be responsible for the low level of protein production. alpha-Galactosidase immobilized by the carboxyl-terminal 67 amino acids of Cwp2p was most effective in the hydrolysis of the high-molecular-weight substrate guar gum from Cyamopsis tetragonoloba. This indicates that the use of a large anchoring domain does not necessarily result in a better exposure of the immobilized enzyme to the exterior of the yeast cell.     

A new reconstruction of the Le Moustier 1 skull and investigation of internal structures using 3-D-μCT data

Using the non-destructive technique of 3-D micro computed tomography (3-D-μCT), we present a new, virtual reconstruction of the Le Moustier 1 Neandertal skull. This new reconstruction corrects defects found in earlier reconstruction attempts by repositioning misaligned cranial fragments, addressing the problem of asymmetry caused by pressure during the fossilization process, and placing the basioccipital in its proper anatomical position. Metric comparisons between Le Moustier 1 and juvenile and adult Neandertals demonstrate that facial height proceeded at a faster rate of growth than facial prognathism at the beginning of the adolescent period. They also confirm the anterior placement of the basioccipital. A compound painted to match the colour of the fossilized bone was used in previous reconstruction attempts and the aim of this analysis was to remove the false material to reveal to what extent the fossilized bone was preserved. The areas with the most artificial material and glue include the palate, areas around the mandibular teeth, the left frontal, and parts of the right parietal and temporal bones. The μCT data were also used to examine internal structures of the skull including the frontal sinus and the labyrinth of the inner ear. An investigation of the frontal sinus reveals morphology similar to that found in adult Neandertals, although the structure does not extend to mid-orbit. The dimension of the radius of curvature of the lateral semicircular canal falls within one standard deviation, and the anterior and posterior canals within two standard deviations, of the published Neandertal mean. As in other Neandertals, the posterior semicircular canal is in an inferior position relative to the plane of the lateral canal.     

The intrinsic microbial stability of water-in-oil emulsions II. Experimental

Summary The microbial stability of water-in-oil emulsions is calculated as a function of the initial contamination, the concentration of carbon and energy sources, the size-distribution of the water droplets and of the storage time. The calculated values appear to be in good agreement with the experimental data.     

General introduction to the importance of genomics in food biotechnology and nutrition

Knowledge of the human genome and other genomes, the selection of health-beneficial components, information and communication technology (ICT)-driven plant cultivation and small-scale processes will together change the agrofoods business from a rather low-tech to a high-tech (functional) foods business. ICT will provide consumers with information that in combination with their private genetic passport may be used to select those functional foods that are most beneficial for them.     

Recovery of heat-injured Citrobacter freundii cells

The influence of various factors in the recovery process of heat-injured cells of Citrobacter freundii has been studied. In particular the temperature of the liquid recovery medium and the residence time of the cells in this medium are important. Cells heated in media with a high osmotic pressure are better recovered in low osmotic liquid recovery media. The influence of the temperature of the solid recovery medium on the decimal reduction time for Ctbt. freundii cells strongly suggests that the number of critical sites to be inactivated before the cell wall be lethally injured also depends on the recovery conditions.     

End-of-life care issues in advanced dementia

Appropriate management of advanced dementia requires it to be recognised as a terminal condition that needs palliative care. Interventions during this stage should be carefully chosen to ensure the improvement or maintenance of the quality of life of the person with dementia. Advanced care planning is an important aspect of dementia care. Carers and relatives should be educated and encouraged to actively participate in discussions related to artificial nutrition, cardiopulmonary resuscitation (CPR) and other medical interventions.     

Reference concentrations of cholecalciferol in animals: a basis for establishing non-target exposure

Abstract

Cholecalciferol (vitamin D₃) is widely used as a vertebrate pesticide in New Zealand. However, cholecalciferol also occurs naturally in animals. Therefore, when trying to determine whether a non-target animal has been exposed to cholecalciferol baits, knowledge of the baseline cholecalciferol concentrations in the animal's plasma and tissue is required. We analysed cattle, sheep, pig, deer, dog and cat plasma and liver samples for the vitamin D₃ metabolite 25-hydroxycholecalciferol (25-OHD), a sensitive biomarker for cholecalciferol. Based on these data and a literature search we present 25-OHD reference ranges. We also examined the literature for 25-OHD concentrations in poisoned animals and compared these to the reference ranges. Where plasma and liver samples have 25-OHD concentrations at least four times higher than our reference ranges it is likely that the animal has been exposed to cholecalciferol baits. 25-OHD concentrations 10 times higher than the reference range indicate ingestion of abnormally high amounts of cholecalciferol.