Drug Target Prediction Using Elementary Mode Analysis in Ascaris lumbricoides Energy Metabolism

K. Parvatham,L. Veerakumari 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.3

Ascariasis, an intestinal worm infection is caused by the parasite Ascaris lumbricoides and a report by World Health Organization (WHO) on soil transmitted helminths suggests that over one billion people are affected by Ascariasis. This disease is prevalent in developing countries, and in places of poor sanitation and unhygienic conditions. Even though anthelminthic drugs are available for the treatment of ascariasis, it is considered as a neglected tropical disease (NTD). Resistance of the parasite to the existing drugs necessitates a detailed study of its energy metabolism for identification of new drug targets. The catabolic pathway of the parasite is an evolved design well suited for parasitic life and obtains constant input from its host. Its energy metabolism is predominantly anaerobic. The parasite mitochondrion plays a key role as it lacks the functional tricarboxylic acid cycle (TCA cycle) and cytochrome oxidase activity. In adult ascarid mitochondrion,there is no external final electron acceptor and endogenously produced fumarate and 2-methyl branched- chain enoyl –CoAs function as the terminal electron acceptors instead of oxygen. In this study, elementary flux mode analysis (EFM),a metabolic pathway analysis tool has been applied to model energy metabolism of the parasite A. lumbricoides. This study identifies a set of enzymes that have been suggested to be essential for the survival of the parasite;the inhibition of these enzymes paralyzes the parasite. The key enzymes of glycolysis and the phosphoenolpyruvate carboxykinase-succinate pathway are identified as drug targets since the knock-out of any of these enzymes results in zero flux value for all EFM that have been identified.

Effect of Mass Drug Administration with a Single Dose of Albendazole on Ascaris lumbricoides and Trichuris trichiura Infection among Schoolchildren in Yangon Region, Myanmar

채종일,손운목,홍성종,정봉광,홍수지,조선,박종복,김인성,김선경,이건훈,Hoo-Gn Jeoung,Thi Thi Htoon,Htay Htay Tin 대한기생충학ㆍ열대의학회 2020 The Korean Journal of Parasitology Vol.58 No.2

Soil-transmitted helminths, including Ascaris lumbricoides and Trichuris trichiura, are important intestinal parasites mostly affecting younger people in developing countries. In 2014-2015, we performed mass fecal examinations targeting a total of 2,227 schoolchildren in 3 districts (South Dagon, North Dagon, and Hlaing-thar-yar) of Yangon Region, Myanmar, using the Kato-Katz thick smear technique. The egg positive children were subjected to a mass drug administration (MDA) using a single oral dose of 400 mg albendazole. The pre-treatment egg positive rate (EPG/person) of A. lumbricoides averaged 17.2% (15,532); it was 25.2% (21,796), 14.2% (11,816), and 12.8% (12,983) in 3 districts, respectively, and that of T. trichiura averaged 19.4% (1,074), and was 24.1% (1,040), 12.3% (852), and 21.2% (1,330) in 3 districts, respectively. Follow-up fecal examinations performed 4 months post-MDA revealed considerable decreases of A. lumbricoides prevalence (EPG/person) to av. 8.3% (12,429), and 13.7% (17,640), 8.0% (7,797), and 4.5% (11,849) in 3 districts, respectively. However, T. trichiura did not show any recognizable decrease in the prevalence (EPG/person) remaining at av. 18.2% (862), and 18.5% (888), 11.5% (812), and 23.3% (887) in 3 districts, respectively. The results demonstrated difficulty in short-term control of T. trichiura by MDA using albendazole and suggested necessity of either a long-term MDA (>10 years) or changing the albendazole regimen into 2~3-day course (total 800 or 1,200 mg), or using an alternative drug/drug combination.

2세 남아에서 충체 배출로 발견된 회충증 1예

조연종,최식경,김수정,Cho, Yeonjong,Choi, Sik Kyung,Kim, Su Jung 대한소아감염학회 2020 Pediatric Infection and Vaccine Vol.27 No.1

Ascariasis is the most common helminthic infection in humans. However, its prevalence has been very low in Korea since the 1990s. Recently, there have been several case reports on intestinal obstruction or pancreaticobiliary disease due to infection with Ascaris lumbricoides in adults. However, cases of ascariasis in children have rarely been reported in Korea. We report a case of ascariasis in a 2-year-old boy who experienced expulsion of an adult ascaris worm from his anus. His mother found the worm in his diaper in the morning. His medical history was nonsignificant for any previous illnesses. There were no specific symptoms, and no abnormal findings were found on physical examination. The worm was pink, elongated, and cylindrical; it was 25 cm long and 5 mm wide. Unfertilized eggs of A. lumbricoides were detected in his stool specimen. He was treated with albendazole and remained asymptomatic at follow-up. As long as the number of immigrants from endemic areas and people returning from overseas trips, and import of agricultural products keep increasing, ascariasis can still occur in Korea. Therefore, it is necessary to raise awareness regarding ascariasis.

여서도패총 출토 분석(糞石)에 관한 연구

안덕임(An, DeogIm),서민(Seo, Min),김건수(Kim, GeonSu) 한국상고사학회 2008 한국상고사학보 Vol.60 No.-

본 연구에서는 선사시대의 식생활, 질병, 고환경 복원 등에 연구목적을 두고 신석기시대의 여서도패총에서 발견된 분석(糞石)에 관한 기생충분석이 시도되었다. 기생충 분석 결과 간흡충(Clonorchis sinensis), 회충(Ascaris lumbricoides), 회충류(Toxocara sp.) 3종의 기생충란이 검출되었다. 시료에서 검출된 기생충란과 시료의 고고학적인 배경을 고려할 때 분석시료는 사람 또는 개의 것으로 판단된다. 회충, Toxocara sp. 충란의 검출로 미루어 당시 위생상태가 그다지 좋지 않았음을 추정할 수 있다. 분석에서 검출된 간흡층란을 통하여 당시의 식습관을 추정하였다. 간흡충란의 감염경로를 고려할 때 분석을 남긴 사람 또는 개는 감염된 민물고기를 날것으로 먹었거나 불완전하게 조리된 상태에서 먹었을 것으로 판단된다. 개가 이러한 먹이를 먹게 된 것은 당시 사람들의 식습관과 관련이 있을 것이다. 개는 사람들이 먹는 음식이나 그 찌꺼기로 사육되며 또 사람들이 버린 음식물 쓰레기 더미를 뒤지고 먹는 습성이 있기 때문이다. 이로 미루어 당시 사람들이 민물고기를 날로 먹는 습속을 가지고 있었을 가능성이 있으며 이로 인해 사람들 사이에 간흡층이 유행하였을 가능성이 있을 것으로 추정된다. 회충류는 비교적 오랜 시간에 걸쳐 전 세계적으로 분표한 기생충이다. 이에 비하여 간흡층은 검출 연대가 늦은데 현재까지 자료에 의하면 본 여서도패총에서 발견된 간흡충란이 고고학적 유적에서 발견된 간흡층란 가운데 세계적으로 가장 오래된 자료일 것이다. In this study, a coprolite from the Neolithic Yoseodo shell midden, Korea, was analyzed to reconstruct palaeodiet, diseases, palaeoenvironment, etc. As a result, the eggs of Clonorchis sinensis, Ascaris lumbricoides and Toxocara sp. were found. On the basis of parasitic and archaeological evidence, it is likely that the coprolite resulted from a man or a dog. From the eggs of Ascaris lumbricoides and Toxocara sp., it can be assumed that sanitary conditions in the past were somewhat poor. The eggs of Clonorchis sinensis can help to infer dietary habits at that time. Considering the infection route of Clonorchis sinensis, the man or the dog that excreted the coprolite ate raw or undercooked freshwater fish, or was fed with them. This might be related with dietary habits of people. Because people feel leftovers of their meals, and because dogs scavenge around refuse heaps, people and dog diets may considerably overlap. Therefore, it is possible that people at that time might have dietary habit of eating raw or undercooked freshwater fish and as a result, Clonorchis sinensis infection might be widespread among people. The eggs of Ascaris lumbricoides and Toxocara sp. habe been recorded worldwide for a relatively long period of time. The eggs of Clonorchis sinensis have been detected for short period of time compared to those of the species, and this is so far the first record of Clonorchis sinensis eggs from archaeological sites in the world.

What was the main factor in successful control of ascariasis in Korea?

조승열,홍성태 대한기생충학ㆍ열대의학회 2023 The Korean Journal of Parasitology Vol.61 No.2

In the l950s, under the legacy of traditional agriculture, Ascaris lumbricoides, spread epidemically in the war-bitten society of Korea. Consensus on the parasite control was drafted in the Parasite Disease Prevention Act, which passed a parliamentary agreement in 1966, and established safe disposal of feces and mass chemotherapy as control strategies. Biannual stool examinations and treating infected schoolchildren were basic scheme of the control activity through which revenue could be secured for organized business. In the 27 years following 1969, a maximum of 16 million stool examinations had been done every year. Cellophane thick smear enabled the task. The infection declined remarkably in the 1970s when industrialization and green revolution proceeded. A population study of A. lumbricoides in the late 1970s helped us better understand its epidemiology. The data also settled down the understandable protest of teachers against the repeated stool examinations. In the 9 years following 1987, the target population was gradually reduced when the egg positive rate was below 0.1%. An article in the Korean Law, stipulating obligatory stool examinations, was made optional. Although the long-term Korean effort of Ascaris control was a success, the effect of mass chemotherapy was not as succinct in terms of lowering reinfection. In the period of control, Korean agricultural technology changed, and the economy grew and supplied sanitary facilities by which the vicious cycle was disconnected. Reduction of morbidity was a benefit of mass chemotherapy, which is the only control method feasible in economically difficult countries. The most important hurdle of parasite control in the 1960s was poverty of general population and limited financial resources in Korea but the society formed a consensus on the priority of intestinal helminthiasis control during the ordeal period. The national consensus in the 1960s was the critical milestone for Ascaris control in Korea. Under the social agreement, application of timely technical and research advancements in parasitology achieved the success of ascariasis elimination. The successful experience of ascariasis elimination in Korea can be a benchmark for countries where neglected tropical diseases are endemically recycled.

V-shaped Pits in Regions of Ancient Baekje Kingdom Paleoparasitologically Confirmed as Likely Human-Waste Reservoirs

Dong Hoon Shin,Sang-Yuck Shim,Myeung Ju Kim,Chang Seok Oh,Mi-Hyun Lee,Suk Bae Jung,Geon Il Lee,Jong-Yil Chai,Min Seo 대한기생충학열대의학회 2014 The Korean Journal of Parasitology Vol.52 No.5

In a paleo-parasitological analysis of soil samples obtained from V-shaped pits dating to the ancient Baekje period in Korean history, we discovered Ascaris lumbricoides, Trichuris trichiura, and Clonorchis sinensis eggs. In light of the samples’ seriously contaminated state, the V-shaped pits might have served as toilets, cesspits, or dung heaps. For a long period of time, researchers scouring archaeological sites in Korea have had difficulties locating such structures. In this context then, the present report is unique because similar kind of the ancient ruins must become an ideal resource for successful sampling in our forthcoming paleoparasitological studies.

A Case of Biliary Ascariasis in Korea

최준호,서민 대한기생충학ㆍ열대의학회 2017 The Korean Journal of Parasitology Vol.55 No.6

Biliary ascariasis is still the leading cause of surgical complication of ascariasis, though its incidence has been dramatically reduced. Herein, we report a case of biliary ascariasis for the purpose of enhancing awareness of parasitic infections as a possible cause. A 72-year-old male visited the emergency room of Dankook University Hospital on 12 July 2015, complaining of right-upper-quadrant pain. By endoscopic retrograde cholangiopancreatography (ERCP), a tubular filling defect in the right hepatic duct was detected. The defect was endoscopically removed and diagnosed as an adult female of Ascaris lumbricoides worm, of 30 cm length. Upon removal of the worm, the pain subsided, and the patient was discharged without any complication. When treating cases of biliary colic, physicians should not neglect biliary ascariasis as the possible cause.

회충란에 의한 간피막의 섬유석회성 결절 1예 보고

서연림,박소영,지제근 대한병리학회 1992 Journal of Pathology and Translational Medicine Vol.26 No.4

Biliary ascariasis misidentified as a biliary stent in a patient undergoing liver resection

채호창,서석원,최유신,손희주,이승은,도재혁,박현정 대한기생충학ㆍ열대의학회 2023 The Korean Journal of Parasitology Vol.61 No.2

Ascaris lumbricoides causes one of the most common soil-transmitted helminthiases globally. The worms mostly infect the human small intestine and elicit negligible or nonspecific symptoms, but there are reports of extraintestinal ectopic ascariasis. We describe a rare case of biliary ascariasis mistaken for biliary stent in a 72-year-old female patient with a history of liver resection. She visited our outpatient clinic complaining of right upper quadrant pain and fever for the past week. She had previously undergone left lateral sectionectomy for recurrent biliary and intrahepatic duct stones 2 years ago. Besides mildly elevated gamma-glutamyl transferase levels, her liver function tests were normal. Magnetic resonance cholangiopancreatography revealed a linear filling defect closely resembling an internal stent from the common bile duct to the right intrahepatic bile duct. A live female A. lumbricoides adult worm was removed by endoscopic retrograde cholangiopancreatography (ERCP). Despite a significant decrease of the ascariasis prevalence in Korea, cases of biliary ascariasis are still occasionally reported. In this study, a additional case of biliary ascariasis, which was radiologically misdiagnosed as the biliary stent, was described in a hepatic resection patient by the worm recovery with ERCP in Korea.

장내 출혈을 수반한 췌십이지장의 동정맥기형에서 시행한 췌장 전절제술 및 췌장도세포 자가이식

한덕종(Duck Jong Han),김송철(Song Cheol Kim),김태희(Tae Hee Kim),위유미(Yu Mi We),조경민(Kyung Min Cho),홍정자(Jung Ja Hong) 대한소화기학회 2001 대한소화기학회지 Vol.38 No.1

Ascaris lumbricoides, the roundworm, is recognized as one of the most prevalent human intestinal helminths in the world, but the positive rate of its egg is markedly decreased recently in Korea. Biliary ascariasis is a relatively common complication of intestinal ascaris infestation and may cause pancreatic ductal obstruction, choledocholithiasis, cholecystitis, cholangitis, hemobilia, and liver abscess. However, there has been no report on biliary ascariasis combined with both bile duct stone and liver abscess in Korea. We experienced a case of having two worms of Ascaris lumbricoides in the bile duct combined with both bile duct stones and liver abscess. The case was managed with endoscopic removal of the worms and stone and with percutaneous drainage of the liver abscess. We report the case with a review of literatures. (Korean J Gastroenterol 2001;38:61-64)