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 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

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 malic dehydrogenase activity was determined by the modified method of Ochoa (1955) using tissue homogenates of various parasitic helminths. Worm parasites were mostly collected from local abattoir, and removed from the organ or tissues of the naturally infected animal hosts, and some materials were also obtained from the human hosts. The helminths used in this experiment include 3 kinds of nematodes, 5 kinds of trematodes, and 8 kinds of cestodes. They were throughly washed and homogenized in glass tissue grinder in ice chilled water bath, and then centrifuged. The supernatants were designated as enzyme preparations. The hydrogen concentrations of buffer solution were pH 1.4, 2.7, 3.5, 4.2, 5.2, 7.4, 8.2, 9.3, 10.2, 11.6, and enzymatic reaction of this experiment was performed at incubation temperature of 20, 30, 40, and 50 C. The extinction of Nicotinamide Adenosine Dinucleotide (NAD) was measured by spectrophotometry at the wave length of 340 millimicron. The results of the experiment were as follows: The malic dehydrogenase activity occurred over all kinds of parasitic helminths used in this study. And the activity on sparganum turned out to be highest. All helminths displayed their maximum activity in the range of alkaline pH. A comparison of the effects of temperature and substrate concentration on the enzyme activity was made among these helminths. However, no definite relationship among them has been detected. The significance of the existence of this enzyme in the helminths was briefly discussed.
parasitology-helminth-trematoda-cestoda-nematoda ; Fasciola hepatica ; Eurytrema pancreaticum ; Paramphistomum sp. ; Taenia solium ; Taenia pisiformis ; Dipylidium caninum ; Diphyllobothrium mansoni ; Cysticercus cellulosae ; Cysticercus fasciolaris ; sparganum ; Ascaris lumbricoides ; Ascaridia galli ; Dirofilaria immitis ; Paragonimus westermani ; Clonorchis sinensis ; malic dehydrogenase-biochemistry-enzyme ; malic dehydrogenase ; Nicotinamide Adenosine Dinucleotide

In order to obtain some informations on the nature and relative activity of the phosphatases present in various helminths, biochemical studies have been made in thirteen kinds of worm parasites including the adults and larvae (Fasciola hepatica, Eurytrema pancreaticum, Paramphistomum sp., Taenia solium, Taenia pisiformis, Dipylidium caninum, Diphyllobothrium mansoni, Cysticercus cellulosae, Cysticercus fasciolaris and Sparganum). A comparison based on the analysis of pH-activity curves was made among these helminths. The worm materials were mostly obtained alive from an abattoir and removed from the organs or tissues of the animal hosts naturally infected. Sparganum and Cysticercus cellulosae, however, are collected from the subcutaneous tissue of the patients by surgical removal. The worms thoroughly washed were weighed and transferred with 0.1 M Tris buffer to a chilled glass grinder (Capacity; 15 ml) and homogenized in the cold. The homogenate was centrifuged at 5000 RPM for 30 minutes. The supernatant was pipetted off for determination of the phosphatase activity. Incubation mixtures consisted of 1 ml substrate, 1 ml buffer and 0.5ml extract. The buffers used were Tris (Hydroxymethyl) aminomethane and citric acid monohydrate and the substrate was paranitrophenyl phosphate (1 gm/25 ml). These mixtures were incubated at the temperature of 37 C for 30 minutes in water bath. The absorbance or transferance of mixture was determined colorimetrically by "Spectronic 20 "spectrophotometer at 410 nm against a distilled water blank. The amount of phenol liberated was then calculated from a standard curve using phenol solutions. Controls consisted of unincubated mixtures. The results were deducted from this experiment. The phosphatase activity occurred over all parasitic helminths used in this experiment. In trematodes, pH-activity curves have demonstrated two peaks of phosphatase activity in Fasciola hepatica and Paramphistomum species. However the acid phosphatase activity was predominantly found and the alkaline phosphatase activity was found distinctly to be low in all three species. In Eurytrema pancreaticum, the pH-activity curves displayed two peaks in acid phosphatase activity, one at pH 5.0 and the other pH 9.0. In cestodes, both alkaline and acid phosphatase activity displayed the pH optima 5.0 and 9.0 to 10.0 in the adult tapeworms. However, major activity in the adults is due to the alkaline phosphtases. In contrast to the adults, Cysticercus and sparganum showed the higher activity in acid phosphatases which predominates in the larvae. In all cases of nematodes, the pH optimum for acid phosphatase was 4.0 to 6.0. A preponderance of acid phosphatase activity was shown in the extract of intestine of Ascaris lumbricoides. The aspect that phosphatases are correlated with phosphorylated passage of substances through the cuticle of helminths and may also be involved in carbohydrate metabolism is discussed.
parasitology-helminth-trematoda-cestoda ; Fasciola hepatica ; Eurytrema pancreaticum ; Paramphistomum sp. ; Taenia solium ; Taenia pisiformis ; Dipylidium caninum ; Diphyllobothrium mansoni ; Cysticercus cellulosae ; Cysticercus fasciolaris ; sparganum ; alkaline phosphatase ; acid phosphatase ; biochemistry

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

By an application of Sigma-Frankel methods, two transaminase systems, glutamic-pyruvic transaminase and glutamic-oxaloacetic transaminase, were found to operate at a mesurable rate in 2 species of nematodes(Ascaris lumbricoides and Ascaridia galli), 5 species of trematodes (Clonorchis sinensis, Fasciola hepatica, Eurytrema pancreaticum, Paramphistomum cervi and Paragonimus westermani) and 5 kinds of cestodes (Diphyllobothrium mansoni, Dipylidium caninum, Taenia pisiformis, Cysticercus cellulosae and Cysticercus pisiformis). A comparison was made of the transamination reactions in nematodes and those of trematodes and cestodes. And the significance of transaminase in these parasites is discussed in relation to protein synthesis and its utilization.
parasitology-helminth-nematoda-trematoda-cestoda ; transaminase ; biochemistry ; spectrophotometry ; Ascaris lumbricoides ; Ascaridia galli ; Clonorchis sinensis ; Fasciola hepatica ; Eurytrema pancreaticum ; Paramphistomum cervi ; Paragonimus westermani ; Diphyllobothrium mansoni ; Dipylidium caninum ; Taenia pisiformis ; Cysticercus cellulosae ; Cysticercus pisiformis

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

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

Control programme of malayan filariasis by diethylcarbamazine was set up in village, Cheju-Island, Korea. The daily dose of 6 mg per kg of body weight for 6 days was chosen as a chemotherapeutic course only for microfilaria positives, which was repeated with an interval of one or two months. For the evaluation of drug control programme the yearly posttreatment blood survey was carried out. The results collected from 1970 to 1973 were analysed from the various points of view, such as microfilaria positive rates, incidence as well as prevalence rates. The change of microfilaria counts was also utilized for the comparison of the intensity of infection among population in the four year blood surveys. Considering the extremely skewed distribution of average microfilaria density, the mode of frequency distribution of microfilaria density in a population was particularly taken into account for the evaluation of changing endemicity affected by diethyecarbamazine treatment. The equation; Y= a+b log X(a , b: constants, X=microfilaria density; Y=probit scale of cumulative frequency of positives to X microfilariae) was found to fit farily well the data collected from four-year surveys before and after treatment. From these data obtained, four regression lines have been drawn by determining "a" and "b"; two paramenters, which were increased year by year since inauguration of control programme. In the present investigation, it was verified that the chmotherapeutic control measure of malayan filariasis applied in a village of Cheju-Island has been successfully carried out and the quantitative level of endemicity inthis area has also been distinctly lowered within the four-year control programme.
parasitology-helminth-nematoda-Brugia malayi ; chemotherapy-diethylcarbamazine ; control ; filariasis ; diethylcarbamazine