The therapeutic effect of praziquantel on Fibricola seoulensis infection were studied by experimental infection of albino rats with the metacercariae obtained from the snakes. Total 51 albino rats were infected each with 500 or 1,000 metacercariae in number through intragastric tubes. One or four weeks later the rats were treated with 1, 5, 10 or 20 mg/kg sigle dose of praziquantel and sacrificed after 3 days or 10-120 minutes to search for the worms in their small intestine. The worms recovery rate at 3 days after the treatment was 10.7% in 1 mg/kg does group and 0.03-0.2% in 5, 10 and 20 mg/kg group, while that of untreated control was 51.3%. The minimum effective dose to treat F. seoulensis infection in the rats is considered to be 5 mg/kg in sigle dose. By observing the distribution pattern of worms in the small intestine after the treatment, dislodgment of the worms froms the duodenum, thier normal habitat, to the lower portion was recognizable within as early as 10 minutes. The majority of worms was found to have descended to the ileo-caecal portion after 60-120 minutes.
parasitology-helminth-trematoda ; Fibricola seoulensis ; chemotherapy-praziquantel

The efficacy of reduced single doses of mebendazole against Ascaris lumbricoides infection was evaluated by cellophane thick smear and egg counting techinques, in two rural populations from December 1977 to March 1978. Total 191 infected cases were divided into five dose groups; 100 mg single dose, 200 mg single dose, 300 mg single dose, 400 mg and 600 mg in repeated doses. The cure rate of mebendazole in the treatment of Ascaris infection was remarkably high and satisfactory in every dose groups. The egg reduction rates were all over 98 percent in every dose groups. Side effects were observed during the treatment, mainly mild and transient gastrointestinal troubles, and not exacerbated by the increase of doses upto 300 mg in single dose. Above results confirmed that in case of mass chemotherapy of Ascaris infection, 100 mg or 200 mg of single dose treatment is sufficient to achieve the economic and acceptable method of treatment.
parasitology-helminth-nematoda ; Ascaris lumbricoides ; chemotherapy-mebendazole

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

A total of 60 patients with Hymenolepis nana infection were treated with a single oral dose of praziquantel in two different dose levels. Twenty-nine cases treated with praziquantel in a single dose of 15 mg/kg body weight produced a 100% cure rate. On the otehr hand, 30 out of 31 patients who received a single dose of 25 mg/kg body weight cured completely, but only one case had counts of 200 EPG of feces in each tests on the 20th and 21st days after treatment. The cure rate was 96.8% and the mean egg reduction rate of 99.8 per cent was obtained. Side effects were mild and transitory. In a few cases, abdominal pain, vertigo, headache and diarrhea were complained in a few hours after medication. Clinial hematology, serum biochemistry and urinalysis were performed immediately before and the next day after treatment in all cases. There were no significant abnormalities detected in these tests.
parasitology-helminth-cestoda ; Hymenolepis nana ; chemotherapy-praziquantel

Ten cases infected with Taenia saginata were treated with Bithionol, 2, 2' thiobis (4,6-dichlorophenol) which is well known as an excellent anthelminthhic against paragonimiasis and their follow-up studies were carried on within 3 to 12 months after treatment. Bithionol, 50 mg dose per kg of body weight was divided into two equal dose and administered orally in 30 minutes intervals. Three hours later, this was followed with a sodium sulfate or magnesium sulfate purge. The strobilas without scolices were found in the stools after the medication and the follow-up studies have shown the complete deworming in all cases. It is well tolerated, toxic effects being uncommon and when present, limited to mild gastro-intestinal disturbances.
parasitology ; helminth ; cestoda ; Taenia saginata ; chemotherapy ; bithionol

The phamacological and anthelmintic action of Lysimachia clethroides were examined. Upon examining the action of water, ether, alcohol and acetone extrcts of the root on smooth muscle, it was found that the active principle was weakened by heating. Water and ether extracts inhibited the dehydrogenase of the worm. In 50 percent of 8 areas studied, Taenia were completely eliminated with 2.5-4.0 gm doses of the ether extracts, and no toxic effect was observed by the administration of the above-mentioned doses.
parasitology-chemotherapy ; Taenia sp. ; Lysimachia clethroides

The anthelminthic effect of phenylene-diisothiocyanate-(1,4)(=Jonit) was studied on the eighty three cases infected with Ancylostoma duodenale. For the evalution, the number of eggs per gram of feces on all these cases was calculated before treatment. The follow-up for the egg reduction was carried out over a period of four weeks. The sixty-seven cases were treated in dosage schedule of 3 x 100 mg every 12 hours. The cure rates - the rate of negative conversion of eggs - was 74.6 percent and the total egg reduction rate of 94.2% was obtained. The ten out of 14 cases treated in the dosage schedule of 2 x 100 mg every 12 hours showed 100% egg reduction and the cure rate was 71.4%. In this group. the total egg reduction rate of 78.6% was noted. In the dosage schedule of 2 x 50 mg every 12 hours the remainder, two out of total 83 cases showed 100% egg reduction. Side effects were observed as being mild, 51 cases (56.6%) were free of side reactions and the most frequently noted side effects were vertigo and diarrhea. From the above results, it is concluded that Jonit is an effective antheminthic against Ancylostoma duodenale and its effectiveness is quite equivalent to that of a known recommended anti-hookworm products.
parasitology-helminth-nematoda ; Ancylostoma duodenale ; chemotherapy ; phenylene-diisothiocyanate ; Jonit

The chronologic growth patten of Ascaris lumbricoides was made by the maximum length of worms collected from inhabitants after mass chemotherapy with pyrantel pamoate by various interval; 2-month, 4-month, 6-month an 12-month. The results obtained were summarized as follows: When the collected 497 worms were plotted on weight/length chart by treatment interval, there was always size limitation in each group, permitting the idea of maximal growth in a given period of infection. The maximum lengths in each interval treatment, 2, 4, 6 and 12-month were; 12.5, 16.4 , 19.2 and 22.8 cm in male and 14.2, 22.0, 26.2 and 30.8 cm in female respectively. The maximum growth curves were expressed by the equations; Y=9.212 In(X+1)+0.025 in male and Y=11.953 In(X+1)+0.025 in female when X is age in month and Y is length in cm. It was revealed that female grew more rapidly than male. The growth of length was rapid in initial 2~3 months and weigth gain was rapid in later than 2~3 months. The weight seems better than length as an indicator of aging.
parasitology-helminth-nematoda ; Ascaris lumbricoides ; chemotherapy ; pyrantel pamoate ; epidemiology ; growth

Atrial to control reinfection cycle of Ascaris lumbricoides was made in a rural village in Korea by blocking the process of new egg production. Chemotherapy with pyrantel pamoate was repeated bimonthly in three hamlet groups, each consisted of 105~149 inhabitants of whole age group. In one hamlet (2.5 mg/kg dose) blanket mass treatment was repeated for 18 times from June 1977 to May 1980. In other two, 5.0 mg and 10.0 mg/kg dose groups, treatment was undertaken for 10 times from June 1977 until December 1987 and later reinfection patten was observed. Follow-up examination was made by whole-day stool collection for 2 days from each case after every treatment. The samples were examined both for eggs and worms, adult and immature young, of A. lumbricoides. The results obtained are summarized as follows: The pre-treatment egg positive rate in Group A, B and C was 48.1, 45.3 an 37.8% respectively. The lowest dose of pyrantel pamoate, 2.5 mg/kg was equally effective as higher doses in case of repeated use for reinfection control. Among 4,311 pyrantel treatments, only 8 cases complained of side effects such as abdominal pain and diarrhea. When the blanket mass chemotherapy was continued 18 times in Group A, all of the examined inhabitants were free from reinfection and egg production from 28th month (the 15th treatment) until the end of study period, for 8 months. When the mass chemotherapy was stopped after 10 times, the egg positive rate returned gradually up to half of pre-treatment level within one year. From the analysis of total 124 positive cases during the course of follow-up, it was revealed that the mass chemotherapy with 2-month interval was successful for the suppression of fertilized egg production. However, social factors such as infected immigrants or absentees were inevitably encountered and involved in the fertilized egg production. Summarizing the results, at least 28-30 months were needed to eradicate A. lumbricoides in the subjected area of Korea, by repeated blanket mass treatment bimonthly with a quarter dose of pyrantel pamoate. Furthermore, to lessen the social factors as a source of later reinfetion, the project area of control programme should be extended as wide as possible.
parasitology-helminth-nematoda ; Ascaris lumbricoides ; chemotherapy ; pyrantel pamoate ; epidemiology

To observe the effect of various interval mass treatment on Ascaris ova and worm positive rates and worm burden per population, 2-month, 4-month, 6-month and 12-month interval schemes were designed and applied. All of inhabitants in nine villages of Hwasung Gun, Kyunggi Do, Korea were treated from April 1977 to May 1980. Each village consisted of 100-140 people, however, there had been 20-40 drop-outs in every treatment. Pyrantel pamoate was used in dose of 10 mg/kg. Evaluation of schemes was made by examinations both for eggs and for expelled worms. The drop-outs in former treatment was included because they were few in munber. The reults obtained were summerized as follows: The pre-treatment infection status of A. lumbricoides was not significantly different between Groups; 32.5-42.2% and 33.8-46.2% in egg and worm positive rates respectively. The mean worm burdens were in range, 1.6-4.2 per infected and 0.61-1.42 per population. Twelve-month interval treatment was by no means meaningful to be adopted as a strategy of Ascaris control because egg and worm positive rates and worm burden were returned to pretreatment level. The shorter the treatment interval was, the lower the egg/worm positive rates and worm burden were. By repeating biannual, triannual and six-times-in-a-year treatments, the indices of prevalence showed the tendency of further lowering during later 2 years of follow-up. If the mass chemotherapy is adopted as a method of controlling ascariasis in a community, it should be repeated more than two times in a year to expect the gradual lowering of reinfection.
parasitology-helminth-nematoda ; Ascaris lumbricoides ; chemotherapy ; pyrantel pamoate ; epidemiology