Predicting changes in oxygen concentration in the headspace of nitrogen flushed packages by the ambient oxygen ingress rate method

The ambient oxygen ingress rate (AOIR) method is an alternative/supplementary method to Ox‐Tran for measuring the oxygen transmission rates of packages. The AOIR method facilitates high‐capacity testing of packages under realistic food storage conditions, on the one hand, and on the other hand provides the possibility to predict the oxygen concentration over time in packages flushed with nitrogen at the time of packaging. The predicted oxygen concentration values showed good agreement with experimental values for flexible packages stored over a period of 91 days at 23°C and 38°C. The prediction of the oxygen concentration in­nitrogen‐flushed packages may be a useful tool, e.g. in shelf life studies, in the selection of the optimal food package as regards to oxygen protection and within quality control purposes. Copyright © 2002 John Wiley & Sons, Ltd.     

Cumulative trauma disorders in the upper extremities: reliability of the postural and repetitive risk-factors index

OBJECTIVE: To determine the extent to which incorporating fat-modified foods into a food frequency questionnaire influences the agreement of energy and nutrient estimates with estimates obtained from food records. DESIGN: Subjects completed four 2-day food records at 3-month intervals. At the end of the recording period, a food frequency questionnaire was administered to assess usual daily intake during the preceding year. SUBJECTS/SETTING: One hundred and three subjects selected from a population-based sample of adults participating in the Beaver Dam Eye Study. STATISTICAL ANALYSES PERFORMED: Subjects were categorized into three groups on the basis of their frequency of consumption of fat-modified foods. For each group, correlations were calculated between food record estimates and estimates obtained from the original food frequency questionnaire, the original with a low-fat option, and the fat-modified questionnaire. RESULTS: For persons categorized as high consumers of fat-modified foods, incorporating questions regarding the consumption of these products resulted in higher correlations with food record estimates (original vs fat-modified version) for percentage of energy from total fat (.32 vs .47), saturated fat (.20 vs .41), oleic acid (.32 vs .50), and linoleic acid (.40 vs .46). High consumers differed in several characteristics that could be associated with disease risk (eg, higher ratios of serum total cholesterol to high-density lipoprotein cholesterol). CONCLUSIONS: Failure to account for the consumption of fat-modified foods in epidemiologic studies may result in misclassification of fat exposures. Because patterns of misclassification could be different for those at risk for disease, results of epidemiologic studies could be biased if these foods are excluded. Thus, incorporating fat-modified foods into food frequency questionnaires will improve the ability of researchers to correctly classify fat exposures and to evaluate potentially important relationships between fat intake and disease risk.     

Primary care--opportunities and threats. Developing prescribing in primary care

The latest white papers on the NHS focus on stimulating innovation in the delivery of primary care and removing barriers to further development. Some of this innovation relates directly to prescribing in primary care, and in this article the authors speculate on what might happen if the prescribing initiatives referred to in the white papers were extended and disseminated more widely. The initiatives which might have the biggest impact are those encouraging closer collaboration between general practitioners and community pharmacists and those aiding extension of the current nurse prescribing scheme in primary care. Both offer considerable opportunities to improve primary care, but both bear some potential risks.     

Studies of structure-activity relationship of nitroxide free radicals and their precursors as modifiers against oxidative damage

The protective effects of stable nitroxides, as well as their hydroxylamine and amine precursors, have been tested in Chinese hamster V79 cells subjected to H2O2 exposure at fixed concentration or exposure to ionizing radiation. Cytotoxicity was evaluated by monitoring the viability of the cells assessed by the clonogenic assay. The compounds tested at fixed concentration varied in terms of ring size, oxidation state, and ring substituents. Electrochemical studies were carried out to measure the redox midpoint potentials. The studies show that in the case of protection against H2O2 exposure, the protection was determined by the ring size, oxidation state, and redox midpoint potentials. In general the protection factors followed the order nitroxides > hydroxylamines > amines. Both the six-membered ring nitroxides and substituted five-membered ring nitroxides were efficient protectors. For six-membered ring nitroxides, the compounds exhibiting the lowest midpoint potentials exhibited maximal protection. In the case of X-radiation, nitroxides were the most protective though some hydroxylamines were also efficient. The amines were in some cases found to sensitize the toxicity of aerobic radiation exposure. The protection observed by the nitroxides was not dependent on the ring size. However, the ring substituents had significant influence on the protection. Compounds containing a basic side chain were found to provide enhanced protection. The results in this study suggest that these compounds are novel antioxidants which can provide cytoprotection in mammalian cells against diverse types of oxidative insult and identify structural determinants optimal for protection against individual types of damage.     

S-phase fraction of 155 soft tissue sarcomas: correlation with clinical outcome

BACKGROUND: Traditionally, grade is considered the most important prognostic factor for soft tissue sarcomas (STS). However, because of the alleged difficulties in reproducibility of grading, new, objectively determined prognostic factors would be of value. The aim of our study was to establish if S-phase fraction (SPF) measured with flow cytometry was of prognostic significance for STS. METHODS: In this study, we included all 193 adult STS patients with superficial trunk or limb tumors who were treated by the Helsinki University Central Hospital (HUCH) STS group between January 1987 and May 1993. One hundred and seventy-two formalin fixed paraffin embedded tumor samples were available. SPF measurement was successful in 155 cases. RESULTS: Eighty-six cases were diploid. Ploidy was found to have no effect on overall survival. The median SPF was 6.8% (diploid tumors, 4% and nondiploid tumors, 12.9%). A high SPF predicted a shorter survival in patients with diploid tumors (P=0.003). The prognostic value was even stronger when we studied disease specific survival and excluded from analysis samples that contained less than 50% tumor cells (P=0.011). However, no prognostic value could be detected in nondiploid tumors or in the material as a whole. CONCLUSIONS: Our results suggest that high SPF is an adverse prognostic factor for survival of patients with diploid STS. However, further studies are needed to confirm these results.