DSpace university logo mark
Advanced Search
Japanese | English 

NAOSITE : Nagasaki University's Academic Output SITE > Institute of Tropical Medicine > Bulletin > Tropical medicine > Volume 12, No. 2 >


File Description SizeFormat
tm12_02_01_t.pdf745.06 kBAdobe PDFView/Open

Title: トキソプラズマのシスト内原虫数の推定と感染マウス脳内シストの発育及び分布について
Other Titles: Estimation of the Number of Parasites contained within a Cyst, and Growth and Distribution of Cysts in the Brains of Mice infected with Toxoplasma gondii
Authors: 本村, 一郎 / 徐, 寛容
Authors (alternative): Motomura, Ichiro / Jo, Kanyo
Issue Date: 20-Aug-1970
Publisher: 長崎大学熱帯医学研究所 / Institute of Tropical Medicine, Nagasaki University
Citation: 熱帯医学 Tropical medicine 12(2). p41-50, 1970
Abstract: I. When separating toxoplasma from man or animal deemed to have died due to toxoplasmosis, brain tissue is often used as the inoculation material. However, using a whole brain for separation of toxoplasma is not easy in that a large number of small experimental animals are required. Accordingly, it becomes necessary to know in what regions of a brain are toxoplasmas distributed more. In the present experiment, the authors used Beverley strain of toxoplasma and examined inoculated mice as to the growth of cysts with the progress of infection and the number of cysts in various brain regions (olfactory lobe, cerebrum, cerebellum, interbrain, pons and medulla). In the brain of mice, cysts were distributed most in the cerebral region throughout the period from 15 days to 210 days after inoculation, accounting for 57.8~86.4% of the total number of cysts. In the meantime, the number of cysts in pons and medulla was smallest, accounting for only 0.5~6.4% of the total numder of cysts. On the other hand, cysts in cerebellum accounted for 2.1~29.2% and those in interbrain 4.9~19.5% of the total number of cysts respectively. From the respective numbers of cysts, the numbers per 1 mg of brain were determined to obtain density indices, as a result of which the index of cerebrum was found to be 120.9~181.3 as against 0~59.1 for pons and medulla, indicating distribution of a large number of cysts in cerebrum. From the results of this experiment, it is considered that cerebrum is suitable as an examination material in an experiment to separate or detect cysts from the brain of mice infected with toxoplasma. II. In the experiment on infection of mice using toxoplasma cysts, the number of inoculated toxoplasmas is expressed in terms of the number of cysts, but it cannot but be said to be an indistinct expression. The reason is that even one cyst varies in its size with the progress of infection and the number of toxoplasmas contained therein is considered to range from scores to tens of thousands. Up to the persent, no report is available, which has elucidated the relation between the size of cyst and the number of toxoplasmas existing in the cysts. In the present experiment, the authors studied the relationship between the diameter of cyst and the number of toxoplasmas involved in the cysts. That is, cysts were purely separated from the brain of mice infected with Beverley strain by multi-layer centrifugation with gum arabic solution (Nakabayashi & Motomura, 1968) and in respect of 72 cysts having a diameter of less than 50μ, cyst diameter and the number of toxoplasmas in the cysts were actually measured. To dissolve cyst membrane, 1% trypsin-Puck solution heated to 37℃ was employed. The numer of all the toxoplasmas escaping from each cyst were measured using a microscope of 400 magnifications. As a result, a regression line of Y=1.04X+0.87 was calculated. In respect of cysts having a diameter of less than 50μ, if one measures cyst diameter and utilizes this regression line, it is possible to estimate the number of toxoplasmas in a cyst simply.
URI: http://hdl.handle.net/10069/4069
ISSN: 03855643
Type: Departmental Bulletin Paper
Appears in Collections:Volume 12, No. 2

Citable URI : http://hdl.handle.net/10069/4069

All items in NAOSITE are protected by copyright, with all rights reserved.


Valid XHTML 1.0! Copyright © 2006-2015 Nagasaki University Library - Feedback Powerd by DSpace