Anti-Clonorchis IgG antibody levels in serum were observed by ELISA in 129 egg positive cases and in 25 controls. The antibody levels were 0.063 to 1.216 (0.325+/-0.202)in clonorchiasis cases and 0.078 to 0.670 (0.255+/-0.133) in controls. The difference was statistically significant. However, serological diagnosis of clonorchiasis was not satisfactory in lightly infected cases because of low levels of specific IgG antibody. The antibody levels were well correlated with EPG. Changes of the IgG antibody levels were not significant 12-14 days, 4 weeks and 8-9 weeks after praziquantel treatment. Seven and 13 months after treatment, the IgG antibody levels were lowered significantly. The period for serologically negative conversion after praziquantel treatment was between 9 weeks and 7 months in human clonorchiasis.
parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis ; chemotherapy-praziquantel ; enzyme-linked immunosorbent assay ; IgG

In an attempt to analyze the clonorchicidal activity of linoleic acid and ethyl linoleate in vitro, the wormicidal effects on Clonorchis sinensis were chronologically monitored in dose titration experiments. Excysted metacercariae were killed within a period of 31.0+-4.0 min, 149.3+-4.l min and 207.0+-13.5 min with 100.0 mg, 0.1 mg and 0.001 mg linoleic acid, respectively. The time required for the linoleic acid to kill adult worms was 167.0+-0.8 min with 100.0 mg, 253.0+-0.8 min with 0.1 mg, and 277.0+-0.8 min at 0.001 mg titration. Clonorchicidal activity of ethyl linoleate was relatively delayed as death was observed within 263.3+-2.9 min, 286.0+-0.5 min, and 318.0+-0.8 min for 100.0 mg/ml, 0.1 mg/ml and 0.001 mg/ml concentrations, respectively. The wormicidal effects observed with these pure anticlonorchal substances were found to be similar to the biological activity of native products derived from the mucus of the fresh water fish.
parasitology-helminth-termatoda ; Clonorchis sinensis ; chemotherapy ; linoleic acid ; ethyl linoleate ; linoleic acid ; ethyl linoleate

The rabbits were infected with Clnorchis sinensis and were treated with praziquantel at the dose of 50 mg/kg x 2 x 2 days afer 1, 2, 4, 8 weeks and 7 months from the infection. Their livers were observed histopathologically 1, 4 and 12 weeks after treatment. The findings are summarized as below: The changes of the liver in control rabbits were relatively mild until 2 weeks after infection. However, widening and thickening of bile ducts, proliferation of biliary epithelium and periductal fibrosis were moderate after 4 weeks from infection and those changes were severe after 8 weeks and 7months. Goblet cell metaplasia was found after 8 weeks from infection. The mild changes of 2-week infection group were completely recovered by 4 weeks after the treatment. In the groups of 4 or more weeks after infection, the changes of bile ducts became milder in the degree after the treatment, but were still found 12 weeks after the treatment. As the infection duration was passed, more severe changes were observed after the treatment. In this context, it is concluded that the liver changes of acute clonorchiasis in the early two weeks are reversible by treatment while chronic biliary epithelial changes are irreversible. Therefore, early treatment should be recommended as possible to minimize the remaining histopathological changes of liver in clonorchiasis.
parasitolgy-helminth-trematoda ; Clonorchis sinensis ; liver ; clonorchiasis ; chemotherapy ; praziquantel ; pathology ; rabbit

This special issue is devoted to a review of the current state of knowledge of clonorchiasis. Sections deal with: the biology of Clonorchis sinensis; geographical distribution, with particular regard to Korea; epidemiology; pathogenesis; clinical features; diagnosis; prevention and control; chemotherapy.
review ; parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis ; epidemiology ; pathogenesis ; liver ; diagnosis ; chemotherapy ; praziquantel ; control ; hetol ; di

Two human cases of Heterophyes heterophyes nocens infection were proved by identifying adult worms after treatment with bithionol or praziquantel in 1983 in Korea. They are 37 (Case 1) and 24-year old (Case 2) males whose residence or native village is a southern coastal area in Kohung-gun, Chollanam-do. The Case 1 had the gastrointestinal symptoms such as epigastric pain and indigestion, and the Case 2 heart problems such as arrhythmia and ventricular premature beat in EKG and digestive symptoms such as diarrhea and abdominal pain. After the treatments, 35 and 67 specimens of H. heterophyes nocens respectively were collected from the diarrheal stools through stereomicroscopy. The Case 1 was concommitantly infected with Clonorchis sinensis and the case 2 with 3 other kinds of heterophyid flukes and with Diphyllobothrium latum. The cases said to have eaten raw brackish water fish such as mullets (Mugil cephalus), perches (Lateolabrax japonicus) and gobies (Acanthogobius flavimanus) which are the intermediate hosts of H. heterophyes nocens in Korea.
parasitology-helminth-trematoda ; Heterophyes heterophyes nocens ; Clonorchis sinensis ; case report ; bithionol ; praziquantel ; chemotherapy ; Mugil cephalus ; Lateolabrax japonicus ; Acanthogobius flavimanus

Praziquantel(Distocide), the Korean product, was tested for its safety and efficacy in treatment of Clonorchis sinensis infection during the period from April to September, 1983 in Korea. A total of 55 egg positive cases were selected and treated with the regimen of 25 mg/kg t.i.d. for 1 day (total 75 mg/kg). The follow-up stool examination was done in 47 cases by cellophane think smear and Stoll's egg counting techniques. The 8 uncured cases were treated again with the same regimen. The laboratory tests for blood picture and liver function were done in 27 cases and compared before and after the treatment. The results obtained are as follows: After single course treatment, the cure and egg reduction rates were 83.0% and 99.1% respectively. With the second treatment, excellent results of 100% in both rates were obtained. Several kinds of side effects such as dizziness, headache, etc. were complained by 29 cases (61.7%), however, those were so mild and transient that no special treatment was necessary. No significant chang in laboratory findings was recognizable before and after the treatment. From the above results, it is concluded that Distocide is as effective and safe as Biltricide and highly recommendable in treatment of C. sinensis infection.
parasitology-helminth-trematoda ; Clonorchis sinensis ; treatment ; chemotherapy-praziquantel ; human ; praziquantel

Experimentally infected rats with 50 metacercariae of Clonorchis sinensis each were treated orally with different dosages of praziquantel. About 100 rats were divided into 8 groups in each developmental week after infection (from the first to 8th week after infection) and 24 rats served as untreated controls. In each developmental week after infection, about 15 rats divided into 4groups including control group(3 to 5 rats) were used to determine for the curative activity of praziquantel against C. sinensis. The experimentally infected rats in each developmental weeks after infection received praziquantel 1 x 100 mg/kg x 3 days , 3 x 100 mg/kg x 1 day and 3 x 100 mg/kg x 2 days. The effects of the drug were evaluated by the worm recovery rates, morphological changes of the worms and the number of eggs per gram of feces (EPG) after treatment. The feces of individual rats were collected once in a week at one week before and 4 weeks after treatment, and the number of Clonorchis eggs were examined by Stoll's egg counting method. The necropsy was performed on 4 weeks after treatment. The liver and the bile ducts were examined immediately after the dissection, and all of the worms recovered from the liver immersed in warm saline solution in a small petri dish in order to observe the motility of individual worms. After that, all worms obtained from the treated and untreated control rats were fixed in 10 percent formalin solution. The whole mount specimens were prepared by Semichon's acetocarmine stain for the study of morphlogical changes. In the treatment with dosage of 1 X 100 mg/kg for 3 consecutive days, relatively low worm recovery rates were shown in the early stages of infection than those of control groups. However there was no differences of the worm recovery rates between the later stages of infection (7 to 8 weeks after infection) and control groups. In the early stages of infection, the worms recovered in the bile ducts of each treated rats showed morphologically intact as normal control groups, however in the later stages of infection the worms showed damage of their reproductive organs such as testes, seminal receptacle and ovary etc. In the treatment with dosage of 3 X100 mg/kg X 1 day, the recovery rates of the worms in all developmental weeks after infection were considerably low and some growth inhibition of the worms were also noted. The worms recovered from the bile ducts in all developmental stages were seriously damaged in their reproductive organs, such as testes, seminal receptacle, ovary, Mehlis' gland, uterus and vitelline glands etc. The hyaline degenerations were also observed on the parenchymal tissues in the dead worms. The mean EPG values in this group were markedly reduced at the first 2 weeks after treatment. However the low values of EPG were generally noted at the 3rd to 4th week after treatment. On the other hand, in the treatment with dosage of 3 X 100 mg/kg X 2 days, no more the living worms was recovered in all developmental stages of Clonorchis . The dead worms recovered from the bile ducts were so seriously damaged that the morphological changes could not be observed. The mean EPG values in this group were markedly reduced during the first 2 weeks after treatment. At the 3rd week after treatment EPG value became negative in the most of all treated groups. No more the Clonorchis eggs were detected at the 4th week after infection, but only a very small numbers of eggs were found by the concentration method. From the above results, it is obvious that praziquantel exhibits a high degree of activity against Clonorchis sinensis in the rats, with no apparent differences in the efficacy against each developmental stage.
parasitology-helminth-trematoda ; Clonorchis sinensis ; chemotherapy-praziquantel ; rat ; praziquantel

The present study was undertaken to observe the morphological changes of Clonorchis sinensis obtained from experimentally infected rats treated with praziquantel (Biltricide) which is a new anthelmintic agent with high activity against a broad spectrum of cestode and trematode species. For this study, the rats were infected experimentally with about 50 metacercariae of C. sinensis and were given praziquantel a single dose of 600 mg per kg of body weight at 5 weeks after infection. The Clonorchis worms were isolated from the bile ducts of the rats which were autopsied on the 4th day after treatment. After isolation the parasites were observed their shape and motility in the medium of 37 C physiological saline solution, and then the fine structure of the tegument of C. sinensis was studied by means of light, scanning and transmission electron microscope. The findings of the observation were compared with those of untreated parasites. The results are as follows: All the isolated worms moved actively in the medium of physiological saline solution (37 C). A majority of the parasites obtained from the treated rats showed a large balloon shaped structure on the surface between oral and ventral suckers. But such structure has never seen in the parasites obtained from control rats. By the scanning electron microscopic observation, the regular pattern of the tegumental ridges was significantly changed on the outer surfaces of parasites obtained from the treated rats as compared with those of the control rats. By the transmission electron microscopic observation, the numerous mitochondriae in the syncytial tegumental layer of the treated parasites appeared to be degenerated and formed small vacuoles, and the tegumental ridges were also degenerated and showed somewhat flattened. In the parasites obtained from the treated rats, a different size of vacuoles interspersed in the distal part of the syncytial tegument and also in subepithelial region of the urinary bladder. These vacuoles are fused each other and lead to the disruption of the apical region of syncytial tegument along the basement layer. Finally the basement layer was dislocated. So that the tegumental layer appeared as a large balloon.
parasitology-helminth-trematoda ; Clonorchis sinensis ; chemotherapy

The present study was undertaken to evaluate in vitro activities of following drugs against adult worms of Clororchis sinensis: i.e., stibnal, chloroquine diphosphate, Hetol (1,4-bis-trichloromethylbenzol), dehydroemetine 'Roche' (Ro 1-9334), niridazole (Ambilhar), bisbendazole, gentian violet, dithiazanine iodide, hexachlorophene, bithionol, niclofolan (Bilevon, Bayer 9015) and praziquantel (Embay 8440, Biltricide). After isolation from bile ducts of experimentally infected rabbits (3 months infection), the parasites were rinsed in sterilized Tyrode's solution and incubated for 24 hours at 37 C in TC 199 medium with Earle's balanced salt solution containing 0, 0.01, 0.1, 1.0, 10 and 100 microgram/ml concentrations of each above drugs. The activities of each concentrations with each drugs were evaluated by the motility of the worms in culture tubes observing at 15, 30, 60 minutes and 2, 4, 6, 12, 18 and 24 hours by stereomicroscope. In the results, no effect was found at the adult worms of C. sinensis in all concentrations with stibnal, chloroquine diphosphate, Hetol, dehydroemetine, niridazole and bisbendazole. However, moderate activities were observed in the concentrations of 1.0 and 0.1 microgram/ml of gentian violet, dithiazanine iodide, hexachlorophene and bithionol. The highest activities were observed in all concentrations of niclofolan and praziquantel.
parasitology-helminth-trematoda ; Clonorchis sinensis ; chemotherapy ; in vitro ; stibnal ; chloroquine diphosphate ; Hetol(1,4-bis-trichloromethylbenzol) ; dehydroemetine ; 'Roche'(Ro 1-9334) ; niridazole(Ambilhar) ; bisbendazole ; gentian violet ; dithiazanine iodide ; hexachlorophene ; bithionol ; niclofolan ; praziquantel

In order to find a highly efficient compound against Clonorchis infection, the anthelmintic activity of disophenol, Tremerad (SYD-230), dithiazanine iodide, dehydroemetine-late-release tablets(RO 1-9334/20), niridazole (Ambilhar), hexachlorophene (G-11), Hetol(1, 4-bis-trichloromethylbenzol) and Bilevon (niclofolan) was tested against Clonorchis sinensis experimentally infected rabbits. All drugs showed a progressive increase in efficacy as the dose rate. They were highly efficient against Clonorchis infection if sufficiently high, potentially toxic doses were given. The efficacy was evaluated by the number of detected worms with vital condition at autopsy after the treatment with above drugs. The high efficacy was observed at the following dose rates of each drugs, i.e. disophenol at a single dose of 30 mg/kg, Tremerad at the daily dose of 200 mg/kg for 10 consecutive days, dithiazanine iodide at the daily dose of 50 mg/kg for 6 consecutive days, dehydroemetine at the daily dose of 10 mg/kg for 10 consecutive days, hexachlorophene at the daily dose of 20 mg/kg for 10 to 15 consecutive days, Hetol at the daily doses from 50 to 100 mg/kg for 5 to 10 consecutive days, and Bilevon at a single dose of 8 mg/kg. Moderate effectiveness was shown in niridazole at the dose of 25 mg/kg for 10 days medication. The use of these anthelmintics for the clinical treatment of Clonorchis sinensis infection is discussed.
parasitology-helminth-trematoda ; chemotherapy-Clonorchis sinensis ; clonorchiasis-rabbit ; disophenol ; Tremerad (SYD-230) ; dithiazanine iodide ; dehydroemetine-late-release tablets(RO 1-9334/20) ; niridazole (Ambilhar) ; hexachlorophene (G-11) ; Hetol(1, 4-bis-trichloromethylbenxol) ; Bilevon (niclofolan)