The morphological characters of the microfilaria of Brugia malayi collected in Cheju-Do, Korea were described and compared with those or other local strains, already reported from the Malay Archipelago(Brug, 1927), Huchow, South China (Feng, 1933), Hachijo Kojima, Japan (Hayashi, 1951) etc. And it was found that there are no marked difference among these kinds of Microfilaria malayi. The percentage measurements of the fixed points in the Microfilaria malayi from Korea are summarized as follows; B.N.C.: 3.38%(2.90-3.72%), N.R.: 22.64% (17.36-25.81%), E.P.: 32.26% (27.49-36.60%), E.C.: 38.78% (34.90-41.72%), Inn. K. begin: 53.95% (49.50-58.84%) end: 67.87%(63.02-72.97%), G-1: 70.42% (60.22-75.23%), G-2:76.70% (75.10-78.32%), G-3:78.84% (77.81-79.59%), G-4:80.84%(79.82-81.35%), A.P.:82.94%(77.32-89.72%), Length: 193.39(+-12.3 micro-meter)(170.77-233.08 micro-meter), Width: 7.04+-0.37 micro-meter(5.99-7.99 micro-meter), Sheath: 268.48+-17.07 micro-meter(218.72-286.47 micro-meter), Ratio(Cephalic space): 1: 0.78
parasitology-helminth-nematoda ; Brugia malayi ; microfilaria

Malayain filariasis in Korea is reviewed in the point of history, parasitology, epdidemiology, pathology and clinical aspects, diagnosis and chemotherapy.
parasitology-helminth-nematoda ; Brugia malayi ; filariasis ; epidemiology ; pathology ; clinical finding ; diagnosis ; chemotherapy ; diethylcarbamazine ; Aedes togoi

The metacercariae of Metagonimus yokogawai were isolated from the sweetfish Plecoglossus altivelis, clollected at Hwagae, South Kyongsang Do, one of the newly known endemic foci of metagonimiasis in Korea. The body structure of metacercaria of M.yokogawai was described and the measurements of the excysted metacercaria were also made. In order to know the distribution of metacercariae within the host, the rate of infection and the intensity of infection, a total of 10 sweet fishes was examined and it was found all infected, from which a total of 38,511 metacercariae was isolated. The number of metacercariae in a fish varied from 219 to 14,427. The average number of metacercaria per fish was 3,851. The distribution of metacercariae in the four divided parts of fish was observed in the following order; number of metacercaria in the muscles; 2,417 (62.8%), in the subcutaneous tissues; 1,126.9 (29.3%), and on the scale; 291.9(7.7%). The development of the metacercaria of M. yokogawai in the mouse host was experimentally traced every day for 10 days after infection . In an earlier period of infection, the growth rate of the genital primordia was distinctly high, particularly in the testes. The seminal receptable and seminal vesicle became clearly recognized in measurable size at 4 days after infection. The vitelline follicles and their ducts were also first visible in the living specimens at 6 days after infection. The oral sucker was larger in size than the ventral sucker in an early stage of the worms, however after 7 days after infection it reversed. The posterior part of body began to extend since two days after infection. Fully matured worms were able to collect only after 7 days after infection. At this stage, the body of worm became 0.7 mm long and 0.3 mm wide. The first positive appearance of eggs in the uterine tubule and in feces was on the 6th day and 10th day of infection, respectively. In an earlier stage of infection, the worms were found mostly in the upper portion of small intestine and the recovery rates of the worms were high, however according to the course of infection in later stage they were seen rather in the lower part of the intestine and the recovery rate also decreased.
parasitology-helminth-trematoda ; Metagonimus yokogawai ; development ; metacercaria ; Plecoglossus altivelis

The occurrence of Sarles' phenomenon (Cerkarien Hullen Reaktion) are proved in the excysted metacercariae of Clonorchis sinensis which were incubated in the sera from rabbits given a varying number of metacercariae of C. sinensis per orally. The precipitates were formed around the oral sucker and excretory bladder of the excysted larvae. Sarles' phenomenon began to be positive from the 2nd to 3rd week after infection. In the excysted larvae of C. sinensis precipitates were not produced in the sera of rabbits infected with Metagonimus yokogawai and Capillaria hepatica. The number of eggs in the feces (E.P.G.), intradermal reaction, the course of infection and Sarles' phenomenon was studied in 6 clonorchiasis patients. Sarles' phenomenon appeared in the sera of some clonorchiasis patients. However, it assumed that this phenomenon correlated with the degree and the course of infection of clonorchiasis.
parasitology-helminth-trematoda-Clonorchis sinensis ; Sarles' phenomena ; rabbit

Since Senoo and Lincicome (1951) first have brought up for attention to the existence of malayan filariasis in Korea, several reports on the epidemiological investigations of the disease had already been made by many workers. However it is little known what kind of mosquitoes are involved as the major vectors in main endemic areas. In Cheju-Do, known as one of main endemic areas in Korea, Aedes togoi is most likely suspected as an important vector because of their abundant collections and vigorous biting attack to human. As a part of studies on filariasis in Korea, an essential preliminary is to determiine whether this mosquito, Aedes togoi collected in the above areas is receptive to the microfilariae of B. malayi. Therefore, the present paper is concerned chiefly with the development of B. malayi in A. togoi. It is also hoped that the studies on the larval morphology in the mosquito host and the structure of microfilariae will provide the base line data required for later investigation of the different vector hosts. The studies were summarized as follows: The measurements of the fixed points in percentage of the body length of microfilariae from the Giemsa stained thick films were made, and they showed that cephalic space was 8 percent,cephalic space length to width, 1.3:1, nerve ring, 21.2 percent, excretory pore, 30.8 percent, excretory cell, 36.5 percent, R1 cell, 66. 5 percent, anus 80.4 percent and body length 202 micrometer(l81-228 micrometer) maximun width 7.6 micrometer. A study on the development of microfilaria malayi in the mosquito, Aedes togoi was carried out at room temperature (24-30 C). Mosquitoes used in this experiment were reared from larvae collected from the tide water rock pool in the coastal areas of Cheju-Do and they were fed with a blood meal of carrier donors whose microfilaria densities were in the range from 0.5 to 0.7 per cmm of blood. All of the microfilariae ingested by mosquito exsheathed in stomach, penetrated into the body cavity and then migrated into the thoracic muscles of the mosquitoes within 10 hours, after two moults in the mosquito host, the length of the developing 3rd stage larvae reached in size of 1.3-1.7 mm x 23-32 microns with anal ratio, 2.6 to 3.6. The first appearance of 3rd stage larvae in the mosquito host in this experiment was in 8th day after infection. The larvae were observed in the various cavities of mosquito, such as head, thoracic cavity, abdomen, halters, eye and legs. During the larval development in larval development in the host, the shortening of body length was first observed and then elnongation was followed until becoming 3rd stage larvae. Aedes togoi was proved to be the most suitable host for this species of microfilaria malayi in the above endemic areas.
parasitology-helminth-nematoda-Brugia malayi ; filariasis ; epidemiology ; mosquito ; life cycle ; vector

Cotylaspis coreensis sp. n., Cotylaspis sinensis Faust et Tang, 1936, Phyllodistomum parasiluri Yamaguti, 1934, Kaurma orientalis Yamaguti, 1937, Astiotrema reniferum (Looss, 1898), Astiotrema odhneri Bhalerao, 1936, Astiotrema sp. and Cephalogonimus japonicus Ogata, 1936 were collected from the intestine of freshwater mud-turtle, Amyda sinensis Wiegmann in Korea which were purchased at Namdaemoon Market of Seoul on October 1968 and May 1977. Cotylaspis coreensis differs from other members of the genus in relatively large size of pharynx, the number and distribution of vitelline follicles, size of testis, length of intestine and position of genital opening. Distribution of Cotylaspis sinensis was firstly recorded in Korea. Phyllodistomum parasiluri collected in this study was considered to be the first to recover from the reptilian host although the collected worms were still immatured. The genus Astiotrema collected in this study were divided into three species, A. reniferum which is hitherto unrecorded in Korea, A. odhneri which had been described as A. orientale, A. amydae and A. fukuii and another Astiotrema sp. which differs from the former two species in minor differences in size of suckers, size of ova and size of cirrus pouch. The distribution of Cephalogonimus japonicus was firstly recorded in Korea.
parasitology-helminth-trematoda ; Cotylaspis coreensis ; Phyllodistomum parasiluri ; Kaurma orientalis ; Astiotrema reniferum ; Astiotrema odhneri ; Astiotrema sp. ; Cephalogonimus japonicus ; turtle-Amyda sinensis ; epidemiology

A series of 250 patients with filariasis due to periodic type of Brugia malayi was selected for the mass treatment with diethylcarbamazine from two areas in Cheju-Do. Two types of dosage schedules have been employed: the one was the conventional dosage schedule (uninterrupted dose of 6 mg/kg once daily 6 times repeated with an interval of one or two month totaling 72 mg/kg), and the other was the low dosage schedule (uninterrupted dose of 0.5, 1, 2, 4, 6 mg/kg body weight given once a day with an additional 6 mg/kg once daily totaling the maximum 37.5 mg/kg). The relative effectiveness of those two schedules was evaluated under the basis of the effects on microfilaria counts and the results of analysis of side-reactions observed. The results obtained in this experiment are summarized as it follows. In the conventional dosage treatment, 118 out of 141 microfilaria positives treated (83.7%) became negative and microfilaria reduction rate was about 99%. However, in the low dosage treatment, 35 out of 43 positives treated (85.4%) became negative and reduction rate of microfilaria, 99.5% in average. Total dose and duration of treatment were 72 mg/kg and about 60 days in the former schedule but it were maximum 37.5 mg/kg and 10 days in the latter. The recurrence of filariasis after treatment in both conventional and low dosage was negligible. Comparative analyses regarding the resulting side-reactions between the two schedules were made on their frequency, severity, onset and duration and relationship with microfilaria density. The febrile reaction was most frequently observed in 80.5% in the conventional, 43.9% in the low dosage schedule. The main side-reactions usually appeared within 6 to 10 hours and lasted 48 to 72 hours in the former threament, however they occurred in 7 to 8 hours and lasted 24 to 43 hours in the latter dosage schedule. It is assumed that the side-reactions are not directly related with the microfilaria count. However, the febrile reaction seems to be correlated with microfilaria density if it is above a certain limit. The presence of adult worm in a lymphnode involved with local reaction was ascertained from the biopsy specimens performed and local reactions such as lymphangitis and lymphadenitis after drug administrations were assessed from clinical and pathological point of view. It was conclusively indicated that the chemotherapeutic response to low dosage schedule within shorter length of treatment was equal to that of larger doses in long term medication from the point of the reduction in microfilaria, and particularly the resulting side-reactions were also reduced in the low dosage schedule.
parasitology-helminth-nematoda-Bruigia malayi ; chemotherapy-diethylcarbamazine ; microfilaria ; diethylcarbamazine

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

The present study attempted to induce an acquired immunity against the dog hookworm, Ancylostoma caninum. The experiments were carried out to demonstrate and confirm whether an acquired resistance could be developed by the repeated lowgrade infections with the infective larvae of A. caninum in the abnormal host of mouse. In order to determined the distribution of hookworm larvae in the lungs and liver of mice after inoculation of infective larvae, 54 mice were inoculated with 1,000 larvae and sacrificed in batches daily up to 9 days after infection. It was found that in all cases the average total number of larvae recovered from the lungs and liver increased at 48 hours after infection, then began to decrease and reached 0 to 1 at the 9th day after inoculation. One hundred fifteen mice were immunized 2 or 4 times at 7 day intervals with 50 infective larvae, followed by challenging infection with 1,000 infective larvae and killed in batches at 48 hours after challenge. The interval between challenge and last immunization were from one to four weeks for each group. Sixty mice as the controls were given only challenging infection without previous immunization infection. Induced resistance was evaluated by the rate of recovery or the average total number of the larvae recovered from the lungs and liver in the challenged mice, compared with the controls. It was noted that the rates of recovery in the controls were twice or nearly higher than those in the previously infected mice in all instances and these remained low for the first 7 day intervals between the last immunizing infection and challenge, then gradually increased. From the above observations it is highly suggested that an acquired resistance can be produced by repeated previous infections with the larvae of A. caninum, even in low grade, in the abnormal host of mouse, and evaluated by the rate of recovery of the larvae after challenge.
parasitology-helminth-nematode-Ancylostoma caninum ; immunology ; recovery rate

Radioactive C(14)-glycine was given to Clonorchis sinensis in Tyrode medium in order to trace the metabolic fate of the labeled carbon. The labeled carbon from glycine enters into every major fraction of Clonorchis sinensis and is highest in the fraction of protein and nucleic acid. Significant amount of C(14)-glycine is incorporated into respiratory carbon dioxide. Relatively high percentage of C(14)-glycine in medium is converted to amino acid fraction and lipid fraction of the worm. In general, glycine is continuously being utilized in the synthesis of proteins and for energy production despite the uptake rate of glycine decreased gradually as incubation proceeds.
parasitology-helminth-trematoda ; Clonorchis sinensis ; metabolism ; biochemistry ; glycine ; amino acid ; nucleic acid ; protein ; lipid ; Tyrode medium