The present study was carried out to examine the effect of "Cortisone" on the worm burden migrated in the organs, and granulomatous change in the liver of mice infected with Toxocara canis eggs. Daily does of 0.5 mg "Cortisone" was administrated subcutaneously to Toxocara-infected mice with different schedule. The results are summarized as follows: More number of Toxocara larvae migrated into the muscle tissue, especially into the carcass through the wall of the large intestine and higher distribution rate and longer persistence of worms were also recognized in the carcass of the experimental group than in the control. Cortisone administration resulted the inhibition of granuloma formation, as well as the resolution of granuloma in the liver. However, the discontinuation of the administration induced the reccurence of heavier grade of inflammation. In non-cortisone treated group (control), cellular infiltration appeared around the worms in the liver on the 10th day of the infection, and typical granulomatosis was followed on the 20th day. As in above results, it is considered cortisone has remarkable anti-inflammatory and immunosuppressive effects in mice infected with T.canis, but histopathological changes on the granuloma formation might be related closely with the duration of Toxocara infection, dosage, duration and timing of cortisone administration.
parasitology-helminth-nematoda-Toxocara canis ; liver ; mouse ; cortisone

It is well established that guinea pig, rabbit and rat are equally susceptible to experimental infection with the Chinese liver fluke, Clonorchis sinensis. However, little work has been done on the studies of the host-parasite relationships between the liver fluke and mouse host. The experiments were undertaken to investigate the susceptibility, development and sexual maturity of Clonorchis sinensis in mouse host. The metacercariae of C. sinensis used in these experiments were isolated from the fish, Pseudorasbora parva by digestion technic. And in all these studies the mice weighing around 20 g were commercially purchased and infected with the metacercariae under slightly narcotized condition with ether. The animals were starved overnight before infection. The mature metacercariae, e.g. 5, 10, 20, 30, 50, 200 were given orally into stomach by means of the polyethylene tubing (intramedic, Clay Adams, Inc.PE-90/S12) respectively to each mouse of groups ranging 4 to l5. After various period of infection, the mouse liver was first opened along the common bile duct and cut into small pieces for collecting and counting the worms. For the histopathological examination of the liver, the tissue specimens were fixed in formalin, sectioned and stained with haematoxylin-eosin. Another experiment was separately set up for the study of egg laying capacity of C. sinensis in mice. The following results were obtained: Mice were successfully infected with metacercariae of C. sinensis in all cases of the groups except the group given 5 and 10 metacercariae, in which the infection was not established in one case of each group. Therefore it is assumed that mice are susceptible to infection with this worm. In an earlier period ot infection, the worms were found mostly in common bile duct and intrahepatic biliary passages with same rate, however in later period, they were seen rather in the intrahepatic biliary passages (73 percent) than in common bile duct and gall bladder. The recovery rate of fully matured adult worms (less than 10 percent) was lower than that of the average recovery rate of the worms in general (22.3 percent). Under same age of infection or even in same host, the size of collected worms showed the great variations. Oral sucker was smaller in size than ventral sucker in the early stage of infection. After 11 days of infection it reversed. The posterior part of body length began to elongate since 5 days after infection, and therefore the ratio of antero-posterior part became l to 3. Fully matured adult worms were only collected after 30 days of infection. The first positive appearance of eggs in feces was on the 17th and 18th day after infection. However, the egg-laying capacity in mouse host seemed to be stabilized since 30 days after infection. Histopathologically, the cystic dilatation of medium to small biliary passages was noted and focal but diffusely scattered necrosis of the liver cells with scarce inflammatory cells was also observed as well as the hepatocellular degeneration, diffuse vascular congestions and adenomatous proliferationof bile duct.
parasitology-helminth-trematoda-Clonorchis sinensis ; mouse ; host-parasite relationship ; worm recovery ; histology ; pathology ; liver

To observe the possibility of human visceral larva migrans due to eating of raw liver of domestic animals, especially of cattle, and also to serve as a good reference for adequate sanitary measures, the investigation survey was carried out from May 1975 to May 1976. From the subjects of a l,048 inhabitants (male 558, female 490) in five localities including two Provinces and three different cities, food habit was studied by questionnaire mannual. Larvae isolated from liver tissues of cattle, and pig were identified. Experimental observation on the chicken and mice infected with Toxocara canis was undertaken to draw a assumption of possibility inducing human visceral larva migrans. The results obtained from the present study are summarized. A part of Korean people has the habit to eat the livers of cattle, fowl, pig and dog raw. Eating rate of raw beef liver was 37.8 percent out of l,048 inhabitants, and its rate was higher markedly in male(57.7 percent) than in female (15. 1 percent), and the highest rate among the group of 31-40 years old. Eating rate of raw liver of fowl was 5.9 percent, pig 5.3 percent, and dog 2.5 percent. Larva recovery rate from beef liver was 11.8 percent out of 195 samples and 72.0 percent of total detected 1arvae were identified as Toxocara(=Neoascaris) vitulorum. From pig liver, larvae of nematoda were found in 6.4 percent out of 109 samples but no larva was detected from 120 fowl livers. Larvae detected from one-half of tissues and organs of infected chicken with about 2,000 Toxocara canis eggs were 8-245 in number, and 85-100 percent of recovered larvae were from their 1iver tissues. Toxocara canis larvae, 45, 31, 42 and 23 in number at 3rd, 14th, 25th and 55th day in one-half of the tissues and organs after infection respectively, were demonstrated from the mice infected with 500 larvae collected from infected chicken liver. Most of the larvae were recovered from the carcass of the mouse. It was approved the larvae isolated from chicken possess infectivity to the mice. Typical eosinophilic granulomatous change was not observed in the liver tissue of the infected chicken at 20th day after infection. As it summarized above, the liver of various domestic animals is the favorite tissue for migration of nematodes larvae. Therefore, the possibility of human visceral larva migrans may be induced due to eating of raw liver of domestic animals.
parasitology-helminth-nematoda ; visceral larva migrans ; Toxocara canis ; liver ; cattle ; fowl ; pig ; dog ; mouse ; chicken ; infectivity

In order to understand the effect of prednisolone injection on the histopathological changes of the mouse liver and the chronological changes of the worm structure of Clonorchis sinensis, when this fluke was inoculated to the mouse intraperitoneally. The recovery rate, survival rate, location and size of the inoculated worms as well as the histopathological changes of the liver were investigated for the comparison among the groups of mice, which were classified by number of worms and the duration of observation period. The result obtained were summarized as follows: The recovery rate and survival rate of the worms decreased especially 28 days after the inoculation. Most of worms (45.5 percent) were collected from the peritoneal cavity, and some of worms were found tightly adherent to the capsules of the liver, spleen, intestine and diaphragm. The mean worm size after inoculation was constantly smaller than that before inoculation. Remarkable atrophy in the reproductive organs of the worm, such as spermatheca, testes, vitelline gland and ovary was frequently observed at the 10th day of inoculation. Histopathologically the liver failed to show any parasitic worm inside the intrahepatic biliary system. However, multiple well formed egg-containing granulomas were present along the liver capsule. These necrotic granulomas were occasionally found under the fibrotic liver capsule. Focal necrosis and focal phlebitis together with vascular dilatation were prominent features of the liver. The worms recovered in the capsule of the liver were degenerated and necrotized. Usually, there were remarkable capsulitis and granuloma formation around the eggs.
parasitology-helminth-trematoda ; Clonorchis sinensis ; histology ; pathology ; mouse-liver ; immunology ; immunesuppression ; necrosis ; phlebitis ; dilatation ; capsulitis ; granuloma