• Parasites, Hosts and Diseases
• /
• 제53권2호
• /
• pp.201-207
• /
• 2015

This study aimed to investigate the infection status, worm development, and phylogenetic characteristics of the intestinal trematode, Stellantchasmus falcatus. The metacercariae of S. falcatus were detected only in the half-beak (Dermogenus pusillus) out of the 4 fish species examined. Their prevalence was 90.0%, and the intensity of infection was 919 metacercariae on average. Worms were recovered from 33 (97.1%) of 34 chicks that were experimentally infected with 200 S. falcatus metacercariae each, and the average recovery rate was 43.0%. The body size and inner organs of S. falcatus quickly increased in the experimental chicks over days 1-2 post-infection (PI). In addition, ITS2 sequence data of this parasite were analyzed to examine the phylogenetic relationships with other trematodes using the UPGMA method. The results indicated that the ITS2 sequence data recorded from trematodes in the family Heterophyidae appeared to be monophyletic. This study concluded that D. pusillus serves as a compatible second intermediate host of S. falcatus in Thailand and that S. falcatus can develop rapidly in the experimental chicks. Data collected from this study can help to close the gap in knowledge regarding the epidemiology, biology, and phylogenetic characteristics of S. falcatus in Thailand.

• Parasites, Hosts and Diseases
• /
• 제57권2호
• /
• pp.135-144
• /
• 2019

There have been some reports on schistosomiasis of school children in Sudan's Nile River basin area; however, information about the infection status of Schistosoma species and intestinal helminths among village residents of this area is very limited. Urine and stool samples were collected from the 1,138 residents of the Al Hidaib and Khour Ajwal villages of White Nile State, Sudan in 2014. The prevalence of overall schistosomiasis and intestinal helminthiasis was 36.3% and 7.7%, respectively. Egg positive rates were 35.6% for Schistosoma haematobium, 2.6% for S. mansoni, and 1.4% were mixed. The prevalence of schistosomiasis was significantly higher in men (45.6%) than in women (32.0%), in Khou Ajwal villagers (39.4%) than in Al Hidaib villagers (19.2%), and for age groups ${\leq}15$ years old (51.5%) than for age groups >15 years old (13.2%). The average number of eggs per 10 ml urine (EP10) of S. haematobium infections was 18.9, with 22.2 eggs in men vs 17.0 in women and 20.4 in Khou Ajwal villagers vs 8.1 in Al Hidaib villagers. In addition to S. mansoni eggs, 4 different species of intestinal helminths were found in the stool, including Hymenolepis nana (6.6%) and H. diminuta (1.0%). Collectively, urinary schistosomiasis is still prevalent among village residents in Sudan's White Nile River basin and was especially high in men, children ${\leq}15$ years, and in the village without a clean water system. H. nana was the most frequently detected intestinal helminths in the 2 villages.

• 생물환경조절학회지
• /
• 제4권2호
• /
• pp.240-245
• /
• 1995

온도 및 광량이 고추냉이의 지상부 및 지하부 생장과 주요 병해발생에 미치는 영향을 조사하기 위하여 생장상의 온도를 10, 17 및 23$^{\circ}C$ 처리구로 하고 차광처리조건을 25, 50 및 75%로 조절하여 실험을 수행하였던 바 그 결과를 요약하면 다음과 같다. 유묘 정식 180일후 조사결과 초장은 생육온도에 따라 차이가 현저히 인정되었으나 17$^{\circ}C$구에서 가장 좋은 결과를 보였으며, 엽병의길이와 직경은 17$^{\circ}C$구를 정점으로 이보다 온도가 높거나 낮음에 따라 감소되는 경향을 보였다. 지하경에 있어서 직경은 1$0^{\circ}C$, 23$^{\circ}C$구간에서는 유의차가 인정되지 않았으며, 17$^{\circ}C$구에서 가장 양호하였다. 길이는 각 처리구별로 유의차가 인정되었으며 역시 17$^{\circ}C$구에서 가장 길었다. 차광처리 75%구가 50, 25%구에 비하여 지하경의 크기는 유의성이 인정되었으나 50%와 25%구의 처리간에는 유의성이 인정되지 않았다. 지하경의 직경과 무게에 있어서 75%구가 기타 처리구에 비하여 양호하였으며 전체 생체중은 75%, 50% 및 25%처리구간에서는 유의차가 인정되었다. 연부병과 묵입병의 발병률은 온도가 증가할수록 증가되었으나 차광량이 많을수록 연부병과 묵입병의 발병율은 감소하는 경향이었다.

• 농촌의학ㆍ지역보건
• /
• 제26권2호
• /
• pp.161-179
• /
• 2001

성주(星州)댐(1994년(年) 담수(潭水) 시작(始作))이 건설(建設)되고, 가야산국민(伽倻山國民)호탤 등(等), 백운동(白雲洞) 집단시설지구(集團施設地區)가 들어선 이후(以後), 대가천(大駕川)에서 채집(採集)되는 담수어(淡水魚)에 있어서 흡충류피낭유충(吸蟲類被囊幼蟲) 기생상(寄生狀)의 변화(變化)를 알아보기 위해 1998년(年) 10월(月)부터 2000년 9월(月)까지 대가천(大駕川)의 상(上), 중(中), 하류(下流)5개처(個處)에서 투망(投網), 낚시, 사발모지 등(等)으로 담수어(淡水魚)를 채집(採集)하였다. 채집(採集)된 어류(魚類)는어종별(魚種別)로 분류(分類)한다음, 어체부위별(魚體部位別)로 흡충류피낭유충(吸蟲類被囊幼蟲)의 기생율(寄生率)을 조사(調査)함과 동시(同時)에 신선(新鮮)한 어육(魚肉)1g 당피낭유충수(當被囊幼蟲數)를 계산(計算)하여 감염도(感染度)를 추정(推定)하였다. 한편, 얻은 결과(結果)를 Lee(1993)의 조사성적(調査成績)과 비교(比較)하였다. 6과(科) 19종(種)의 어류(魚類)에서 8정(種)의 흡충류피낭유충(吸蟲類被囊幼蟲), 즉 간흡충(肝吸蟲), Centrocestus armatus, Cyathocotyle orientalis, Exorchis oviformis, Metagonimus sp ecies, Metacercaria hasegawai, Metorchis orientalis, Clinostomum complanatum, 및 소속미정(所屬未定) 흡충류(吸蟲類) 피낭유충(被囊幼蟲)A와 C를 검출(檢出)할 수 있었다. 대체(人體)에 기생(寄生)하는 간흡충(肝吸蟲)의 피낭유충(被囊幼蟲)은 7종(種)의 어류(魚類)에서 검출(檢出)할 수 있었고, 그 기생율(寄生率)은 1993년(年) Lee의 조사성적(調査成績)에 비(比)해 낮았으며, 기생도(寄生度)는 적었다. Metagonimus species 피낭유충(被囊幼蟲)은 1993년에서는 11종(種)의 어류(魚類)에서 검출(檢出)할 수 있었으며 그 율(率)은 최소(最小)1.2%, 최대(最大)33.3%의 감염율(感染率)을 나타내었는데 비(比)하여, 이번 조사(調査)에서는 6종(種)의 어류(魚類)에서 검출(檢出)할 수 있었으며, 그 율은 4.3- 20.0%이였다. 기생도(寄生度)는 1993年의 조사성적(調査成績)에 비(比)해 낮았다. Exorchis oviformis 유충(幼蟲)은 5종(種)의 어류(魚類)에서 검출(檢出)할 수 있었으며, Cyathocotyle orientalis는 7종(種), Metacercaria hasegawai는 9종(種), Centrocestus armatus는 3종(種), Clinostomum complonatum은 2종(種)의 어류(魚類)에서 검출(檢出)할 수 있었으며, 그 기생율(寄生率)과 기생도(寄生度)는 어종별(魚種別)로 큰 차이(差異)를 나타내었다. 비늘, 지느러미와 꼬리에 있어서 흡충류(吸蟲類) 피낭유충(被囊幼蟲)의 기생율(寄生率)은 너무 변동(變動)이 심(甚)하여 1993년(年)의 그 율(率)과 비교(比較)할 수 없었으나, 대체(大體)로 낮았다. 이상(以上)의 성적(成績)으로 보아 성주(星州)댐 건설(建設)과 가야산국민(伽倻山國民)호탤 등(等), 백운동(白雲洞) 집단시설지구(集團施設地區)가 들어선 이후(以後), 대가천(大駕川)에 서식(棲息)하고 있는 담수어(淡水魚)에 있어서 간흡충(肝吸蟲)을 위시(爲始)한 각종(各種) 흡충류(吸蟲類) 피낭유충(被囊幼蟲) 기생율(寄生率)과 기생도(寄生度)는 댐 담수(潭水)를 시작(始作)하기 전(前)(1994년)보다 낮음을 알았다.

• Parasites, Hosts and Diseases
• /
• 제58권6호
• /
• pp.701-707
• /
• 2020

A survey was performed to investigate the infection status of zoonotic helminth larvae in fish from a local market of North Dagon District in Yangon City, Myanmar. A total of 486 fish in 13 species were collected 8 times from December 2015 to December 2019. All fish were transported under ice to a laboratory in Korea and examined for helminth larvae using artificial digestion method. Larval gnathostomes and metacercariae of more than 8 zoonotic trematode species, i.e., Opisthorchis viverrini, Haplorchis taichui, H. pumilio, H. yokogawai, Centrocestus spp., Stellantchasmus falcatus, Pygidiopsis cambodiensis, and Procerovum sp., were detected. Larval gnathostomes were found in 58 (16.0%) out of 362 fish of 6 species, with mean intensity of 2.8 per fish infected. Metacercariae of O. viverrini were detected in 10 (2.9%) out of 349 fish of 5 species, with mean intensity of 16.9 per fish infected. Metacercarial prevalences of 4 intestinal flukes, H. taichui, H. pumilio, H. yokogawai, and Centrocestus spp., were 16.8%, 26.0%, 12.5%, and 15.0% in the positive fish species, respectively, and mean metacercarial intensity was 63.3, 26.8, 86.2, and 8.7 per fish infected. Metacercariae of S. falcatus and P. cambodiensis were detected only from the mullet, Chelon macrolepis. Metacercariae of Procerovum sp. were found in Channa striata and Anabas testudineus. Collectively, it was confirmed that the fish were infected with gnathostome larvae and metacercariae of O. viverrini and intestinal flukes in Yangon City, Myanmar.

• Journal of Korean Medical Science
• /
• 제33권49호
• /
• pp.314.1-314.15
• /
• 2018

Background: Despite its growing significance, studies on the burden of disease associated with natural disasters from the perspective of public health were few. This study aimed at estimating the national burden of disease associated with typhoons and torrential rains in Korea. Methods: During the period of 2002-2012, 11 typhoons and five torrential rains were selected. Mortality and morbidities were defined as accentual death, injury and injury-related infection, and mental health. Their incidences were estimated from National Health Insurance Service. Case-crossover design was used to define the disaster-related excess mortality and morbidity. Disability-adjusted life years (DALYs) were directly assessed from excess mortality and morbidity. Results: The burden of disease from typhoons increased with the intensity, with 107.7, 30.6, and 36.6 DALYs per 100,000 per event for strong, moderate, and weak typhoons, respectively. Burden of disease from torrential rains were 56.9, 52.8, and 26.4 DALYs per 100,000 per event for strong, moderate, and weak episodes, respectively. Mental disorders contributed more years lived with disability (YLDs) than did injuries in most cases, but the injury-induced YLDs associated with strong typhoon and torrential rain were higher than those of lower-intensity. The elderly was the most vulnerable to most types of disaster and storm intensities, and males younger than 65 years were more vulnerable to a strong torrential rain event. Conclusion: The intensity of torrential rain or typhoon was the strongest determinant of the burden of disease from natural disasters in Korea. Population vulnerable may vary depending on the nature and strength of the disasters.

• Biomaterials and Biomechanics in Bioengineering
• /
• 제2권3호
• /
• pp.127-141
• /
• 2015

Silver-based systems activated by low intensity direct current continue to be investigated as an alternative antimicrobial for infection prophylaxis and treatment. However there has been limited research on the quantitative characterization of the antimicrobial efficacy of such systems. The objective of this study was to develop a semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model providing the quantitative relationship between the critical system parameters and the degree of antimicrobial efficacy. First, time-kill curves were experimentally established for a strain of Staphylococcus aureus in a nutrientrich fluid environment over 48 hours. Based on these curves, a modified PK/PD model was developed with two components: a growing silver-susceptible bacterial population and a depreciating bactericidal process. The test of goodness-of-fit showed that the model was robust and had good predictability ($R^2>0.7$). The model demonstrated that the current intensity was positively correlated to the initial killing rate and the bactericidal fatigue rate of the system while the anode surface area was negatively correlated to the fatigue rate. The model also allowed the determination of the effective range of these two parameters within which the system has significant antimicrobial efficacy. In conclusion, the modified PK/PD model successfully described bacterial growth and killing kinetics when the bacteria were exposed to the electrically activated silver-titanium implant system. This modeling approach as well as the model itself can also potentially contribute to the development of optimal design strategies for other similar antimicrobial systems.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권5호
• /
• pp.1751-1758
• /
• 2015

There has been a strong, positive correlation between opisthorchiasis-associated cholangiocarcinoma and infection with Helicobacter. Here a rodent model of human infection with Opisthorchis viverrini was utilized to further investigate relationships of apparent co-infections with O. viverrini and H. pylori. A total of 150 hamsters were assigned to five groups: i) Control hamsters not infected with O. viverrini; ii) O. viverrini-infected hamsters; iii) non-O. viverrini infected hamsters treated with antibiotics (ABx); iv) O. viverrini-infected hamsters treated with ABx; and v) O. viverrini-infected hamsters treated both with ABx and praziquantel (PZQ). Stomach, gallbladder, liver, colonic tissue, colorectal feces and O. viverrini worms were collected and the presence of species of Helicobacter determined by PCR-based approaches. In addition, O. viverrini worms were cultured in vitro with and without ABx for four weeks, after which the presence of Helicobacter spp. was determined. In situ localization of H. pylori and Helicobacter-like species was performed using a combination of histochemistry and immunohistochemistry. The prevalence of H. pylori infection in O. viverrini-infected hamsters was significantly higher than that of O. viverrini-uninfected hamsters ($p{\leq}0.001$). Interestingly, O. viverrini-infected hamsters treated with ABx and PZQ (to remove the flukes) had a significantly lower frequency of H. pylori than either O. viverr-iniinfected hamsters treated only with ABx or O. viverrini-infected hamsters, respectively ($p{\leq}0.001$). Quantitative RT-PCR strongly confirmed the correlation between intensity H. pylori infection and the presence of liver fluke infection. In vitro, H. pylori could be detected in the O. viverrini worms cultured with ABx over four weeks. In situ localization revealed H. pylori and other Helicobacter-like bacteria in worm gut. The findings indicate that the liver fluke O. viverrini in the biliary tree of the hamsters harbors H. pylori and Helicobacter-like bacteria. Accordingly, the association between O. viverrini and H. pylori may be an obligatory mutualism.

• 대한의생명과학회지
• /
• 제6권2호
• /
• pp.119-129
• /
• 2000

피부는 인체의 표면을 보호하는 중요한 기관으로 피부가 손상되었을 경우 상처 재생은 염증기, 상피화기, 수복기의 정상적인 재생 단계를 거치며 치유된다 최근 저강도 레이저의 생물학적 효과로서 상처 재생과의 밀접한 관련성이 알려지고 있다. 본 연구는 저강도 레이저가 상처 재생에 미치는 유의한 효과를 세포 형태학적으로 확인하기 위해 실험적으로 유도한 가토 피부 상처 (2$\times$2 cm)에 12일 동안 5 Hz, 830 nm, 1.6 J/$cm^2$의 자극강도 (10 min/day)로 상처면에 레이저를 적용한 결과, 다음과 같은 곁과를 얻었다. 레이저 조사군의 경우 결합조직의 수복과 상피의 재형성이 대조군과 비교했을 매우 빠르게 진행되는 것으로 관찰되었으며, 특히 섬유아세포의 활성과 육아조직 합성율이 유의하게 증가되는 것으로 확인되었다. 이상의 연구 곁과를 종합해 달 때 유효한 치료강도의 저강도 레이저 자극은 피부의 개방성 창상 및 욕창 등의 상처 치유를 촉진할 수 있는 것으로 사료된다.

• 한국콘텐츠학회논문지
• /
• 제17권7호
• /
• pp.437-442
• /
• 2017

최근 자기공명신호를 형성시키지 않는 보상물질을 이용하여 신호강도를 높이려는 연구가 활발히 진행되면서 검사부위에 보상물질을 직접 부착함에 따른 환자감염의 우려가 나타나고 있다. 이에 본 연구에서는 발상의 전환으로 보상물질을 코일에 간접 부착함으로써 기존의 직접 부착방식을 대체할 수 있는지 알아보고자 하였다. 연구방법은 보상물질인 실리콘을 원통형 bar의 형태로 제작하여 8채널 head 코일의 element에 부착한 후, 실리콘 부착 전 후 water phantom의 신호강도를 측정하였다. 영상획득은 3.0T 초전도 자기공명영상장치와 8채널 head 코일을 이용하여 T1, T2강조영상을 획득하였으며, 획득한 영상은 영상측정프로그램을 이용하여 신호강도를 측정한 후, 대응표본T검정을 이용하여 유의한 차이가 있는지 판단하였다. 부착 전 후 신호강도는 T1 강조영상은 3.39%, T2 강조영상은 2.62% 유의하게 증가하였다. 결론적으로 간접 부착방식은 증가율이 낮아 모든 환자를 대상으로 대체하기에는 한계가 있을 수 있지만, filling factor의 증가로 인한 신호강도의 의미있는 상승이 있으므로 당뇨병 등 감염성 질한 우려 환자에 적용 시 유용하리라 판단된다.