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The relationship between prior growth of food-spoilage yeast in high-sugar environments and their subsequent survival postpulsed UV (PUV) irradiation was investigated. Test yeast were separately grown to early stationary phase in YPD broth containing increasing concentrations of glucose (1-50% w/v) and were flashed with ≤40 pulses of broad-spectrum light at lamp discharge energy settings of 3.2, 7.2 and 12.8 J (equivalent to UV doses of 0.53, 1.09 and 3.36 μJ cm−2, respectively) and their inactivation measured. Findings showed that prior growth in high-sugar conditions (≥30% glucose w/v) enhanced the sensitivity of all nine representative strains of Zygosaccharomyces bailii, Z. rouxii and Saccharomyces cerevisiae yeast to PUV irradiation. Significant differences in inactivation amongst different yeast types also occurred depending on amount of UV dose applied, where the order of increasing sensitivity of osmotically stressed yeast to PUV irradiation was shown to be Z. rouxii, Z. bailii and > S. cerevisiae. For example, a 1.2-log order difference in CFU mL−1 reduction occurred between Z. bailii 11 486 and S. cerevisiae 834 when grown in 50% w/v sugar samples and treated with the uppermost test UV dosage of 3.36 μJ cm−2, where these two yeast strains were reduced by 3.8 and 5.0 log orders, respectively, after this PUV treatment regime compared to untreated controls. The higher the UV dose applied the greater the reduction in yeast numbers. For example, a 1.0-, 1.4- and 4.0-log order differences in CFU mL−1 numbers occurred for S. cerevisiae 834 grown in 15% w/v sugar samples and then treated with PUV dose of 0.53, 1.09 and 3.36 μJ cm−2, respectively. These findings support the development of PUV for the treatment of high-sugar foods that are prone to spoilage by osmotolerant yeast. [ABSTRACT FROM AUTHOR]

The use of at-line NIRS to monitor a high cell density fed-batch baker's yeast bioprocess was investigated. Quantification of the key analytes (biomass, ethanol and glucose) and the product quality indicator (percentage protein content) was studied. Biomass was quantitatively modelled using whole matrix samples (as was percentage protein content). The dominance of the whole matrix spectrum by biomass, and its associated light scattering effects, were overcome by use of filtrate samples and adapted (semi-synthetic) filtrate samples, which allowed successful ethanol and glucose modelling, respectively. Calibrations were rigorously challenged via external validation with large sample sets relative to the calibration sample size, ensuring model robustness and potential practical utility. The standard errors of calibration for biomass, glucose, ethanol and total intracellular protein were (g/l) 1.79, 0.19, 0.79 and 0.91, respectively, comparable to those of the primary assays. The calibration strategies necessary to generate quantitative models for this range of analytes in such a complex high cell density bioprocess fluid are discussed. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Pichia pastoris expression system is being used successfully for the production of various recombinant heterologous proteins. Recent developments with respect to the Pichia expression system have had an impact on not only the expression levels that can be achieved, but also the bioactivity of various heterologous proteins. We review here some of these recent developments, as well as strategies for reducing proteolytic degradation of the expressed recombinant protein at cultivation, cellular and protein levels. The problems associated with post-translational modifications performed on recombinant proteins by P. pastoris are discussed, including the effects on bioactivity and function of these proteins, and some engineering strategies for minimizing unwanted glycosylations. We pay particular attention to the importance of optimizing the physicochemical environment for efficient and maximal recombinant protein production in bioreactors and the role of process control in optimizing protein production is reviewed. Finally, future aspects of the use of the P. pastoris expression system are discussed with regard to the production of complex membrane proteins, such as G protein-coupled receptors, and the industrial and clinical importance of these proteins. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article cites a study which investigates the interactive effects of race, recidivism, and type of crime in incarcerated adult males on the Problem Solving Inventory and Minnesota Multiphasic Personality Inventory (MMPI) scales. The MMPI is an objective personality inventory that is used to assess abnormal behavior. Subjects were 52 volunteers selected from a pool of 61. Nine subjects were discarded from the sample because of missing data. Some of the significant results found in the analyses of these data are limited in their interpretability because the scale score means fall within the normal ranges of MMPI scores.

The article looks at the future prospects in the urine-based markers in bladder cancer. Primarily, the authors discuss selected evolving markers that include survivin, DNA-based methylation assays, c-Met and BLCA-4. They opine that while these markers appear to raise hope, this is tempered by the reality that more studies are necessitated to further validate their effectiveness.