Two monographs on malaria and the parasites of malarial fevers / I. Marchiafava and Bignami, II. Mannaberg.

  • New Sydenham Society
Date:
1894
Catalogue details

Licence: Public Domain Mark

Credit: Two monographs on malaria and the parasites of malarial fevers / I. Marchiafava and Bignami, II. Mannaberg. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    then washes in water, or, if over stained, first in alcohol. The mixture is always made just before use. The two solutions used for this purpose can be kept for a long time, and indeed the solution of methylene blue stains best when the formation of mould is noticed upon its surface. The solution is filtered before use. When the two stains are mixed a heavy precipitate occurs ; the solution, however, must not be filtered, but used together with the precipitate. Komanowsky assumes that in his mixture a third neutral colour develops, to which the nuclear network of the liEematozoon shows the greatest affinity. With this method the protoplasm of the malarial parasite is stained blue (Prussian blue), the nuclear cromatin (nucleolus) carmine violet; the results are often very beautiful; still thick precipitates often occur, and the formation of the neutral violet is not infrequently missing, in which case the nuclear chromatin is also stained blue like the protoplasm. I have [49] suggested staining the parasites with haematoxylin after fixing them with picric acid. This method I employ at the present time with slight modifications in the following way : The dry preparation is first floated for about five minutes upon distilled water, then dried between blotting paper, and then drawn several times through a veiy weak solution of acetic acid (one drop of acetic acid to 20 cm. distilled water) until it has completely given up its haemoglobin. Thereafter the prepara- tion, which is now almost completely colourless, is placed for two hours upon the following fixing solution : Saturated watery solution of picric acid . . 30 Distilled water . . . . -30 Glacial acetic acid . . . .1 from which it is transferred to absolute alcohol for another two hours. Thereafter follows the staining during twelve to twenty-four hours in alum haematoxylin.^ Lastly, differentiate (clear up) by means of acid, alcohol (75 per cent, alcohol with 0*25 per cent, of hydrochloric acid added) and ammonia alcohol (three drops of ammonia to 10 c.c. alcohol, 75 per cent.), then wash in 80 per cent, alcohol and mount in xylo-Oanada balsam. The washing of the preparation with water and acetic acid removes the albumen, which is apt to give rise to troublesome precipitates in the following 1 I used a fairly old solution of 10 grammes of crystallised hsematoxylin in 100 grammes of absolute alcohol. Just before use one part of this solution is mixed with two parts of a half per cent, solution of ammonia alum.