PubMed · 11103467
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S Carlson. 2000. Calibrating with cold.. https://doi.org/10.1038/scientificamerican1200-102
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BACKGROUND: In 2000, the World Health Organization (WHO) had eight sets of conflicting recommendations for decontaminating medical equipment. We conducted a systematic review of observational studies to assist WHO in reconciling the various guidelines. This paper summarises the methods developed and illustrates the results for three procedures--alcohol, bleach and povidone iodine. METHODS: We developed a Medline search strategy and applied inclusion criteria specifying the decontamination procedures of interest and an outcome of microbial destruction for a set of marker organisms. We developed protocols to assess the quality of studies and categorised them according to the reliability of the methods used. Through an iterative process we identified best practice for the decontamination methods and key additional factors required to ensure their effectiveness. We identified 88 published papers for inclusion, describing 135 separate studies of decontamination. RESULTS: For disinfection with alcohol, best practice was identified from 23 studies as an exposure to 70-80% ethanol or isopropanol for at least 5 minutes. Bleach was effective for sterilization at a concentration of 5000 ppm for 5 minutes and for disinfection at 1000 ppm for 10 minutes (33 studies). Povidone iodine was only partially effective for disinfection at a concentration of 1% for 15 minutes (15 studies). CONCLUSIONS: Our findings provide an evidence base for WHO guidelines on decontaminating medical equipment. The results support the recommended use of bleach and show that alcohol could be used more widely than current guidelines suggest, provided best practice is followed. The effectiveness of povidone iodine is uncertain.
To discriminate 'alcoholics' and 'non-alcoholics', individual Alc-Indices (determined by methanol, acetone, 2-propanol, gamma-GT and CDT-concentrations) were calculated in a collective of 327 alcohol-impaired drivers with regard to the blood alcohol concentration, the time of the event and the age of the drivers. Applying this new defined Alc-Index, 48% of the drivers investigated could be characterised as alcohol dependent. The prevalence of alcoholics among individuals with blood alcohol concentrations (BAC) higher than 1.9per thousand was more than 80%. The diagnostic value of alcohol concentrations for the recognition of 'alcoholics', considering the legal limit in Germany (1.1per thousand) as well as statistically calculated limits, were compared to the Alc-Index.
A reproducible high-resolution protein separation method is the basis for a successful differential proteome analysis. Of the techniques currently available, two-dimensional gel electrophoresis is most widely used, because of its robustness under various experimental conditions. With the introduction of narrow range immobilized pH gradient (IPG) strips (also referred to as ultra-zoom gels) in the first dimension, the depth of analysis, i.e. the number of proteins that can be resolved, has increased substantially. However, for poorly understood reasons isoelectric focusing on ultra-zoom gels in the alkaline region above pH 7 has suffered from problems with resolution and reproducibility. To tackle these difficulties we have optimized the separation of semipreparative amounts of proteins on alkaline IPG strips by focusing on two important phenomena: counteracting water transport during isoelectric focusing and migration of dithiothreitol (DTT) in alkaline pH gradients. The first problem was alleviated by the addition of glycerol and isopropanol to the focusing medium, leading to a significant improvement in the resolution above pH 7. Even better results were obtained by the introduction of excess of the reducing agent DTT at the cathode. With these adaptations together with an optimized composition of the IPG strip, separation efficiency in the pH 6.2-8.2 range is now comparable to the widely used acidic ultra-zoom gels. We further demonstrated the usefulness of these modifications up to pH 9.5, although further improvements are still needed in that range. Thus, by extending the range covered by conventional ultra-zoom gels, the depth of analysis of two-dimensional gel electrophoresis can be significantly increased, underlining the importance of this method in differential proteomics.