Report on the blood changes following typhoid inoculation / by W. B. Leishman.

  • Leishman, W. B. (William Boog), 1865-1926.
Date:
1905
Catalogue details

Licence: In copyright

Credit: Report on the blood changes following typhoid inoculation / by W. B. Leishman. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

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    !•—Method of collecting the blood and of iiooling the serum of the Groups. The fing’er was first well scrubbed with a pledget of wool soaked iu lysol, the lysol being removed by the free application of absolute alcohol. When the latter had evaporated, a prick was made with a sterile needle, and the blood Cf'Uected in a sterile capsule. Four small racks were provided, one for the capsules of each group, and as each capsule was filled it was placed in its appropriate rack. The capsules were then placed in the incubator at 37” C. for two hours, when the serum was separated from the clot of centrifugaliza- tion. The serum of each group was then pooled” by drawing equal volumes from each capsule into the bulb of a sterile pipette which was then sealed off at both ends aud vigorously shaken to secure a thorough mixture. Each of the four bulbs was then carefully marked in a permanent manner so as to obviate any chance of subsequent confusion. In no case was an experiment lost through contamination of the serum collected and pooled in this way. 2.—Preparation of the daily Stock Culture. The stock culture of the “ R ” strain of B. Ujphosus which was used in the daily estimations was planted out every day at the same hour fi-om the 24 hours’ growth in broth inoculated the day before. The same loop was used throughout and no more than the ring of the loop was dipped in the culture, which had previously been well shaken, and used to inoculate the new tube of broth which contained exactly 10 c.c. It was hoped in this way to secure a fairly constant strength of culture for each day’s use. In the earlier part of the investigation it did keep fairly constant, but towards the end the growth became rather more vigorous from the continual daily planting. 3.—Method of diluting and counting of the Stock Culture. This was done daily, as it was felt to be of great importance in connection with the measurement of the bactericidal power of the serum. The method adopted, after much preliminary experimental work, was as follows:—Two series of test tubes were accurately graduated to contain respectively 9 c.c. and 10 c.c., marks being made on the glass corresponding (o these volumes of fluid, these were sterilised and kept ready for use. Two pipettes were employed, one calibrated in the manner devised by Dr. right to deliver 10 c.mm. of fluid, the other an ordinary 1 c.c. pipette. In making the 1 in 10,000 dilution of the daily culture, employed in the bactericidal estimations, the culture was first vigorously shaken, 1 u.c. was then added by means of a sterile pipette to a test tube of broth filled up to the 9 c.c. mark, the resulting 1 in 10 dilution was