A national survey of skin health in nursing personnel.

BACKGROUND: Hand dermatitis is a well-established occupational risk in nursing staff. AIMS: To explore skin health in nursing staff and to develop resources and recommendations to promote good skincare at work. METHODS: Cross-sectional survey. RESULTS: We analysed data from 1,545 surveys. Forty-six percent reported 'poor' skin health and the majority (93%) experienced at least one skin problem over the previous 12 months, with only 22% seeking help from their employer. Only 2% took time off work due to skin problems, with many expressing concerns that taking sick leave would be viewed negatively by others. Over half (53%) had reduced or stopped using antibacterial rubs and soap, and 18% had reduced the use of gloves. Most respondents used hand cream and over half used products they had purchased themselves. Only 42% received skin health care information from employers, with fewer (26%) receiving training on how to identify early signs of skin disease. Only 16% had access to skin surveillance in line with regulatory requirements. Only 26% of respondents were aware of the support offered by their professional nursing association. Suggestions for improving skin health included increasing publicity concerning the importance of skin health in healthcare settings, improving access to hand creams, better quality products, enhanced education and training and more involvement from Occupational Health (OH). CONCLUSIONS: Results confirm that poor skin health remains a persistent problem for nurses. Employers could do more to promote skin health and nurses need to be made more aware of the support and guidance offered by professional bodies.

Enhanced production of human recombinant proteins from CHO cells grown to high densities in macroporous microcarriers.

Macroporous microcarriers entrap cells in a mesh network allowing growth to high densities and protect them from high shear forces in stirred bioreactor cultures. We report the growth of Chinese hamster ovary (CHO) cells producing either recombinant human beta-interferon (ß-IFN) or recombinant human tissue-plasminogen activator (t-PA) in suspension or embedded in macroporous microcarriers (Cytopore 1 or 2). The microcarriers enhanced the volumetric production of both ß-IFN and t-PA by up to 2.5 fold compared to equivalent suspension cultures of CHO cells. Under each condition the cell specific productivity (Q (P)) was determined as units of product/cell per day based upon immunological assays. Cells grown in Cytopore 1 microcarriers showed an increase in Q (P) with increasing cell densities up to a threshold of >1 × 10(8) cells/ml. At this point the specific productivity was 2.5 fold higher than equivalent cells grown in suspension but cell densities above this threshold did not enhance Q (P) any further. A positive linear correlation (r (2) = 0.93) was determined between the specific productivity of each recombinant protein and the corresponding cell density for CHO cells grown in Cytopore 2 cultures. With a cell density range of 25 × 10(6) to 3 × 10(8) cells/ml within the microcarriers there was a proportional increase in the specific productivity. The highest specific productivity measured from the microcarrier cultures was ×5 that of suspension cultures. The relationship between specific productivity and cell density within the microcarriers leads to higher yields of recombinant proteins in this culture system. This could be attributed to the environment within the microcarrier matrix that may influence the state of cells that could affect protein synthesis or secretion.

High productivity of human recombinant beta-interferon from a low-temperature perfusion culture.

Recombinant human interferon-beta (ß-IFN), used in the therapeutic treatment of multiple sclerosis (MS), can be produced on a large-scale from genetically engineered Chinese hamster ovary (CHO) cells. However, its hydrophobicity causes non-reversible, molecular aggregation in culture. The parameters affecting aggregation were determined to be concentration, culture residence time, temperature and glycosylation. Although the protein can be produced in Escherichia coli in a non-glycosylated form, the addition of glycans confers a reduced rate of aggregation as well as a 10-fold higher bioactivity. We report on the application of a low temperature perfusion culture designed to control the parameters that cause aggregation. In this three-phase culture system there is a transition to a low temperature (32°C) in a batch mode prior to implementing perfusion at 1 volume/day using an acoustic cell separator. Perfusion at the low temperature resulted in a 3.5-fold increase in specific productivity and a 7-fold increase in volumetric productivity compared to the batch culture at 37°C. The percentage aggregation of ß-IFN was reduced from a maximum of 43% in batch culture to a minimum of 5% toward the end of the perfusion phase. The glycosylation profile of all samples showed predominantly sialylated biantennary fucosylated structures. The extent of sialylation, which is important for bioactivity, was enhanced significantly in the perfusion culture, compared to the batch culture.

Microwave frequency sensor for detection of biological cells in microfluidic channels.

We present details of an apparatus for capacitive detection of biomaterials in microfluidic channels operating at microwave frequencies where dielectric effects due to interfacial polarization are minimal. A circuit model is presented, which can be used to adapt this detection system for use in other microfluidic applications and to identify ones where it would not be suitable. The detection system is based on a microwave coupled transmission line resonator integrated into an interferometer. At 1.5 GHz the system is capable of detecting changes in capacitance of 650 zF with a 50 Hz bandwidth. This system is well suited to the detection of biomaterials in a variety of suspending fluids, including phosphate-buffered saline. Applications involving both model particles (polystyrene microspheres) and living cells-baker's yeast (Saccharomyces cerevisiae) and Chinese hamster ovary cells-are presented.