• Parasites, Hosts and Diseases
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• 제56권2호
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• pp.189-194
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• 2018

To determine that Paragonimus sp. is actively transmitted in a tropical area of the Pacific region of Ecuador where human cases of pulmonary paragonimiasis have recently been documented, a total of 75 freshwater crabs were collected from 2 different streams in the Pedernales area of $Manab\acute{i}$ Province, Ecuador. All collected crabs were identified as Hypolobocera guayaquilensis based on morphological characteristics of the male gonopods. The hepatopancreas of each crab was examined by compressing it between 2 glass plates followed by observation under a stereomicroscope. Excysted Paragonimus metacercariae were detected in 39 (52.0%) crabs and their densities varied from 1 to 32 per infected crab. There was a positive relationship between crab size and metacercarial density. Sequences of the second internal transcribed spacer region of the ribosomal RNA gene of the Paragonimus metacercariae obtained in this study were identical to those of Paragonimus mexicanus deposited in the DDBJ/EMBL/GenBank database. Thus, the present study is the first to confirm that the crab species H. guayaquilensis is the second intermediate host of P. mexicanus in $Manab\acute{i}$ Province, Ecuador. Because this crab might be the possible source of human infections in this area, residents should pay attention to improper crab-eating habits related with a neglected parasitic disease, i.e., paragonimiasis.

• The Plant Pathology Journal
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• 제19권6호
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• pp.269-273
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• 2003

A total of 57 isolates of Colletotrichum gloeosporioides were recovered from diseased tissues of Hall's crab apple (Malus haliana), 3 cultivars of edible apple (M. pumila var. dulcissima), red pepper (Capsicum annum), and grapevine (Vitis vinifera) fruits. All isolates showed strong virulence on their own host plants. Isolates from edible apple exhibited high level of cultivar specificity in pathogenicity tests. Ten isolates from apple cultivar 'Fuji' were virulent on 'Jonathan' and 'Rall's Genet'. However, 12 isolates from 'Jonathan' and 'Rall's Genet' were not virulent on 'Fuji'. Among the 24 isolates from red pepper, only seven and two isolates were infective on edible apple and grapevine fruits, respectively. All six isolates from grapevine were only virulent on their own host. These isolates were grouped into five vegetative compatibility groups (VCGs), A, B, C, D, and E, by demonstrating heterokaryosis through complementation using nitrate-nonutilizing (nit) mutants. Among them, isolates belong to VCG-A and VCG-D accounted for 24 and 17 isolates； those in VCG-A exhibited wide host range involving Hall's crab apple, all three edible apple cultivars, and red pepper. On the other hand, isolates of VCG-D and VCG-E showed limited host range specific to red pepper and grapevine, respectively. Taken together, the data suggest that among C. gloeosporioides isolates, the concepts of pathotype and/or forma specialis may exist, and that three is a relationship between host specificity and VCG grouping among C. gloeosporioides isolates.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.199-204
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• 2007

Metacercariae of Gynaecotyla squatarolae (Digenea: Microphallidae) were discovered from the shore crab, Macrophthalmus dilatatus, purchased at a market in a coastal town of Taean-Eup, Chungcheongnam-do, Republic of Korea. Their adult flukes were confirmed by experimental infection of rats. The metacercariae of G. squatarolae were elliptical ($391.1{\times}362.5{\mu}m$), and the excysted metacercariae had progenetic genital organs, including the ovary and testes. To obtain adult flukes, 6 Sprague-Dawley rats were fed 500 metacercariae each, and killed at days 2, 4, and 6 post-infection. The adult flukes were identified as G. squatarolae (Yamaguti, 1934) Yamaguti, 1939, based on morphological characters, including 2 ventral suckers (1 large and 1 small), a large genital atrium equipped with the cirrus and the metraterm, separated male and female genital pores, a transversely long cirrus pouch, and extensive vitelline follicles. In the present study, it has been first proven that the shore crab M. dilatatus is a second intermediate host for G. squatarolae in the Republic of Korea.

• Animal Systematics, Evolution and Diversity
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• 제40권4호
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• pp.302-307
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• 2024

Carcinothoe haustra n. gen. n. sp. feeding on eggs of the three-spotted swimming crab Portunus sanguinolentus is described from Korean waters. Choniosphaera indica Gnanamuthu, 1954, which was previously described as copepod parasitic on the same species of the crab from India, is transferred to Carcinothoe n. gen. As two significant synapomorphic features in the female of the new genus, the antennule is 5-segmented and the caudal ramus is transformed into an elongate stylet. As other diagnostic features in the female of the new genus, the body is elliptical, unsegmented, and slightly compressed laterally, the urosome is completely fused with the prosome, the caudal rami are fused with abdominal region, the genital region is positioned on the ventral surface and partly covered with a pair of genital plates, the antenna is 4-segmented with two denticulate spines distally, the maxillule bears two setae on the precoxal endite and three apical setae on the unsegmented palp, the maxilla is 2-segmented, and the maxilliped is 4-segmented and tipped with a denticulate spine. Carcinothoe haustra n. gen. n. sp. differs from C. indica n. comb. in having an anteroventrally protruded buccal region, the antennule which is remotely separated from the buccal region, and no legs.

• Biotechnology and Bioprocess Engineering:BBE
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• 제3권2호
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• pp.71-77
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• 1998

The strain of Serratia marcescens QM B1466 produces selectively large amount of chitinolytic enzymes (about 1mg/L medium). Enzymatic hydrolysis of chitin to N-acetyl-${\beta}$-D-glucosamine (NAG) was performed with a system consisting of two hydrolases (chitinase and chitobiase) produced by optimization of a microbial host consuming chitin particles. For the development of Large-scale biological process for the production of NAG from chitinaceous waste, the selection and optimization of a microbial host, particle size of crab/shrimp chitin sources and initial induction time using chitin as a sole carbon source on chitinase/chitobiase production and NAG production were examined. Crab-shell chitin(1.5%) treated by dilute acid and , ball-milled with a normal diameter less than 250m gave the highest chitinase activity over a 7 days culture. Crude chitinase/ chitobiase solution obtained in a 10 L fed-batch fermentation showed a maximum activities of 23.6 U/mL and 5.1 U/mL, respectively with a feeding time of 3 hrs, near pH 8.5 at 30$^{\circ}C$.

• Parasites, Hosts and Diseases
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• 제47권1호
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• pp.25-29
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• 2009

Paragonimus harinasutai metacercariae were found in a species of freshwater crab, Indochinamon ou, collected in a small stream of Namback District, Luang Prabang Province, Lao PDR. Adult flukes were recovered after experimental infection of the metacercariae to dogs. Metacercariae were round or slightly elliptical, $0.666{\times}0.626\;mm$ in average size, and had a thin cyst wall of about $20{\mu}m$ in thickness, a black excretory bladder, convoluted ceca, and some pinkish materials in the body. Adults were somewhat elongated, $95.2{\times}36.5\;mm$ in average size, covered with single-tipped tegumental spines, had a smaller oral sucker than the ventral sucker, a moderately branched ovary, and 5-6 lobulated testes. Eggs were ovoid and bilaterally symmetrical in shape, $79{\times}45{\mu}m$ in average size, and had a uniformly thickened shell. By the present study, it has been confirmed that I. ou is a new second intermediate host for P. harinasutai.

• BMB Reports
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• 제38권2호
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• pp.128-150
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• 2005

Invertebrate animals, which lack adaptive immune systems, have developed other systems of biological host defense, so called innate immunity, that respond to common antigens on the cell surfaces of potential pathogens. During the past two decades, the molecular structures and functions of various defense components that participated in innate immune systems have been established in Arthropoda, such as, insects, the horseshoe crab, freshwater crayfish, and the protochordata ascidian. These defense molecules include phenoloxidases, clotting factors, complement factors, lectins, protease inhibitors, antimicrobial peptides, Toll receptors, and other humoral factors found mainly in hemolymph plasma and hemocytes. These components, which together compose the innate immune system, defend invertebrate from invading bacterial, fungal, and viral pathogens. This review describes the present status of our knowledge concerning such defensive molecules in invertebrates.

• Animal Systematics, Evolution and Diversity
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• 제7권2호
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• pp.257-264
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• 1991

바지락에 공생하는 굴속살이게의 제 1조에아 유생에서 그 형태적 특징을 기술 및 도시하였다. 본종은 액극.배극.측극.이 없고 제 1소악과 제2소악의 내지가 각각 0.4, 1.2(3)의 강모를 제2악각의 내지가 2분절로 0.4의 강모를 가져 속살이게속의 유생특징을 잘 나타내고 있다. 그러나 제 1.2소악의 저절.기절.강모수가 이미 보고된 Muraoka와 Konishi(1997),Konishi(1983)의 것과 다를뿐만 아니라 숙주도 Mytilus 속이 아닌 Tapes이므로 한국산 바지락내에 공생하는 굴속살이게의 상세한 기재가 요청된다.

• Archives of Plastic Surgery
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• 제37권4호
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• pp.485-488
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• 2010

Purpose: Paragonimiasis is infectious disease occurred by Paragonimus Westermani, which invades into human body as a final host. Habitual eating the freshwater crab or crawfish unboiled is one of the reason of infection. Paragonimiasis raged in 1970s in Korea, Japan, China and other Asian countries but the incidence decreased rapidly. Once people eat infected second host, parasite penetrates the duodenal wall and migrates to the lung. During this migration period, the parasite can migrate to other organ, such as brain, spinal cord, liver and subcutaneous tissue, but the cases are rarely reported. The objective of our study is to present our experience of the ectopic migration of parasite to the subcutaneous tissue of the abdomen, which was easily treated with excision and Praziquantel medication. Methods: A 59-year-old woman who likes eating unboiled freshwater crab was diagnosed as Paragonimiasis 15 months ago. Her symptoms were fever and cough, and she was treated with Praziquantel medication. 3 months after discharge, she visited our hospital with left pleuritic chest pain, cough with fever, and palpable mass formation on left lower quadrant of the abdomen. Wedge resection of the left lung and Praziquantel medication was maintained for a week. Nevertheless, fever persisted after the treatment. The patient received total excision of the abdominal soft tissue mass, and the fever was relieved. Results: Pathologic findings of the mass showed multiple cyst and abscess formation with crystal structure which is suspicious parts of the parasite or calcified egg shells. Uncontrolled fever was relieved after the operation, and there was no evidence of recurrent Paragonimiasis and ectopic migration for 1 year follow up period. Conclusion: Ectopic migration of Paragonimus is rare, but multiple organ can be involved. Patient with Paragominiasis who was refractory in fever control after Praziquantel medication or surgical evaluation of the lung should be considered as ectopic migration of the Paragonimiasis.

• 한국수산과학회지
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• 제18권6호
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• pp.581-585
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• 1985

1981년 8월에서 1982년 5월까지 일본 암수현 대퇴만에서 섶 속살이게, Pinnotheres pholadis에 기생된 진주담치를 정기적으로 채집하고 기생군과 비기생군간의 각장에 대한 육중의 상관관계를 조사하고, 그 성숙도와 영양상태의 차를 조직학적 방법에 의해 구명했다. 섶 속살이게의 기생으로 말미암아 진주담치는 증육에 명백한 장해를 받음이 밝혀졌다. 또한, 생식선의 발달이 늦어질뿐 아니라, 생식세포의 수가 감소됨으로써 전체면적에 대한 생식선의 면적비가 낮아지게 되므로, 기생군의 번식력은 비기생군에 비해 현저하게 약한 것으로 추정된다.