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THE work of Tillmans et al. [1932], of Harris and Ray [1933] and of others on the estimation of vitamin C by titration against phenolindophenol has offered an opportunity to investigate quickly the antiscorbutic activity of foodstuffs. Since no information in this respect was available regarding Canadian foods, it seemed advisable to make a series of measurements. It was soon found that several modifications in the available procedures could be made to render the estimation more convenient and more accurate. We have employed the procedure of Harris and Ray [1933] with the following modifications.(a) The indicator, 2:6-dichlorophenolindophenol, was made up in a phosphate buffer solution, PH 7-2. In this solution the indicator was found to be fairly stable, but daily standardisation is essential.(b) The indicator was standardised against ferrous ammonium sulphate according to the method of Tillmans, Hirsch and Hirsch [1932]. Since both ferrous ammonium sulphate and ascorbic acid reduce the indophenol indicator, it was possible, through the medium of the indicator, to standardise the sulphate solution against pure ascorbic acid crystals. The slightly acidified solution of ferrous ammonium sulphate when kept under an atmosphere of nitrogen in an automatic burette showed no. deterioration in 6 months.(c) As was first noted by Zilva [1927], acid alone slowly decolorises the indophenol indicator. When titrating extracts rich in ascorbic acid the percentage error caused by the presence of trichloroacetic acid is negligible but in solutions with a low ascorbic acid content the percentage error is considerable. The time required for a given amount of trichloroacetic acid to decolorise a fixed amount of indophenol solution is considerably increased when the indophenol solution is diluted with 15-20 vols. of water. On the other hand, the same dilution only slightly prolongs the time required for the reduction of the indophenol by ascorbic acid. Consequently in this work 1 0 ml. of the indophenol indicator solution was diluted with 15-20 ml. of distilled water just prior to titration with the acidified ascorbic acid extract.(d) When working with solid foods Birch et al. [1933] made only one trichloroacetic acid extraction. One extraction yields only about 60 % of the free ascorbic acid contained in the tissue and it is essential to make three extractions in order to obtain an estimate of the total amount of free ascorbic acid.(e) A final concentration of 5% trichloroacetic acid was found to have a destructive effect on various ascorbic acid extracts. A 3% solution was found to serve equally well for extraction and considerably lessened the destructive action.(f) The addition of a few drops of potassium cyanide solution during extraction was found to have a stabilising effect on the ascorbic acid present.(g) The use of larger volumes than those recommended by Birch et al. increases the accuracy of the procedure. In this work tissues were extracted as follows. To 72 g. of the solid material were added 48 ml. distilled water...

This study was carried out to further the available information on adult cases of human metapneumovirus (hMPV), a recently described cause of respiratory infection. Among a cohort of 741 symptomatic patients tested since 2003, the virus was diagnosed in six adults using reverse transcriptase polymerase chain reaction. Of the six, two were from the community, two were hospital inpatients with chronic obstructive pulmonary disease and two were immunocompromised patients, both of whom required ventilation and later died. This report discusses the clinical features, epidemiology and diagnosis of hMPV, highlighting that this infection may be associated with death in high-risk adults. For adults presenting with respiratory symptoms and a background of pre-existing respiratory disease or who are immunocompromised, nucleic acid-based techniques are a cost-effective means of making the viral diagnosis in a clinically relevant time frame.