Comparative morphology of minute intestinal fluke eggs that can occur in human stools in the republic of Korea

The egg morphology of minute intestinal flukes (MIF) that can occur as human infections in the Republic of Korea, i.e., Metagonimus yokogawai, M. miyatai, M. takahashii, Heterophyes nocens, Heterophyopsis continua, Stellantchasmus falcatus, Stictodora fuscata, Pygidiopsis summa, and Gymnophalloides seoi, was studied in comparison with Clonorchis sinensis. The adult worms were obtained from residents of endemic areas, and their intrauterine eggs were studied and measured using light microscopy; the length, width, length-width ratio (LWR), and Faust-Meleney index (FMI). Several specimens were processed for scanning electron microscopy (SEM), and before gold-coating, the uterine portion of each fluke was etched with a sharp pin in order to expose the eggs. The MIF eggs were ovoid, pyriform, or elliptical with a size range of 21-35×12-21 μm. S. fuscata eggs revealed the highest FMI (largest in the area) and lowest LWR, whereas P. summa eggs showed the lowest FMI and medium LWR. SEM revealed that G. seoi and S. fuscata had remarkably clean shell surface lacking the muskmelon-like structure which is prominent in C. sinensis eggs. In Metagonimus spp., H. continua, H. nocens, and S. falcatus eggs, minute surface ridges were recognizable though less prominent compared with C. sinensis. On the surface of P. summa eggs, thread-like curly structures were characteristically seen. The results revealed that important differential keys for MIF eggs include the length, width, area (FMI), shape of the eggs, and the extent of the muskmelon-like structure or ridges on their shell surface and operculum.     

Food-borne intestinal trematode infections in the Republic of Korea

A total of 19 species of food-borne intestinal trematodes have been reported in humans in the Republic of Korea. They include 12 species of the Heterophyidae, Metagonimus yokogawai, M. takahashii, M. miyatai, Heterophyes nocens, H. heterophyes (imported), H. dispar (imported), Heterophyopsis continua, Pygidiopsis summa, Stellantchasmus falcatus, Centrocestus armatus, Stictodora fuscata, and S. lari; four species of the Echinostomatidae, Echinostoma hortense, E. cinetorchis, Echinochasmus japonicus, and Acanthoparyphium tyosenense; and one species each of the Neodiplostomidae, Neodiplostomum seoulense, Plagiorchiidae, Plagiorchis muris, and Gymnophallidae, Gymnophalloides seoi. Fresh water fish harbor the metacercarial stage of M. yokogawai, M. takahashii, M. miyatai, C. armatus, E. hortense, E. cinetorchis, E. japonicus, or P. muris. Brackish water fish serve as the second intermediate hosts for H. nocens, H. continua, P. summa, S. falcatus, S. fuscata, and S. lari. Brackish water bivalves are the source of infection with A. tyosenense. Tadpoles and frogs are the second intermediate hosts for N. seoulense, but the major source of human infection is the grass snake Rhabdophis tigrina, a paratenic host. The metacercariae of G. seoi are observed in oysters. The natural definitive hosts are, in most cases, mammals such as rats, cats and dogs. However, several species (C. armatus, S. lari, E. japonicus, A. tyosenense, and G. seoi) have birds as natural definitive hosts. Host-parasite relationships, pathogenesis and pathology, immunity, clinical aspects, differential diagnosis, treatment, prevention and control of these intestinal trematodes are briefly discussed.     

Molecular markers for identification of Stellantchasmus falcatus and a phylogenic study using the HAT-RAPD method

Stellantchasmus falcatus is a minute intestinal fluke in the family Heterophyidae. Metacercariae, the infective stage, were reported in a marine fish, mullet Liza subviridis, and a fresh water fish, Dermogenus pusillus, in Thailand. Adults were found in chicks, rats, cats, and humans. Morphological studies were done for comparing Stellantchasmus sp. worms found in 2 different fish hosts; their shapes and organ arrangements were very similar except for the prepharynx length. Therefore, the present study aimed to compare their DNA fingerprints using the HAT-RAPD method for both types of Stellantchasmus and several other related species. Ten arbitrarily selected primers (OPA-04, OPA-09, OPN-02, OPN-03, OPN-09, OPN-12, OPP-11, OPR-15, OPX-13, and OPAD-01) were used. It was found that OPA-09, OPN-03, and OPAD-01 were able to generate S. falcatus specific fragments in mullets which consisted of 200, 760, and 280 bp, respectively. In addition, the results of morphologic, DNA fingerprinting, and phylogenetic analyses strongly suggest that the fresh water and marine specimens of Stellantchamus may be different species.     

Cipangopaludina chinensis malleata (Gastropoda: Viviparidae): a new second molluscan intermediate host of a human intestinal fluke Echinostoma cinetorchis (Trematoda: Echinostomatidae) in Korea

Two species of the viviparid snails have been reported in Korea, e.g., Cipangopaludina chinensis malleata and Cipangopaludina japonica. Cipangopaludina chinensis malleata collected at 3 of 12 localities were found to be infected with metacercariae of Echinostoma cinetorchis, one of the snail-borne human intestinal trematodes in Korea. Metacercariae from these snails were fed to rats (S/D strain), and adult worms of E. cinetorchis, characterized by 37-38 collar spines on the head crown, were recovered from the ileocecal regions. However, no C. japonica collected from 2 localities harbored the metacercariae. In experiments with laboratory-bred viviparid snails, all viviparids were not susceptible to miracidia of E. cinetorchis. To confirm the identity of second intermediate hosts of E. cinetorchis experimentally, 2 species of viviparid snails were exposed to the cercariae from Segmentina hemisphaerula that had been infected with miracidia of E. cinetorchis. Both species of snails were susceptible to cercariae of E. cinetorchis. This is the first report of Cipangopaludina spp. serving as the second intermediate host of E. cinetorchis and as a potential source of human infection.     

The biology of Penthaleus species in southeastern Australia

Earth mites are major pests of pastures and crops within southern Australia. While the biology and ecology of the redlegged earth mite (Halotydeus destructor) have been studied extensively, the blue oat mite (Penthaleus major) and its recently discovered relative, Penthaleus falcatus, have received little attention. The distribution of H. destructor, P. major and P. falcatus is described in Victoria, Australia, and the inland borders in central New South Wales are re-described. A new undescribed Penthaleus species identified from mallee samples is recognized, and its restricted distribution in Victoria is mapped. Electrophoretic data and the complete absence of males indicate that all Penthaleus species are obligate thelytokous parthenogens. The three Penthaleus species differ in clonal diversity. All species are pests of pastures and/or crops, however the preferred plant hosts of P. major and P. falcatus differ. Tolerance of a commonly used pesticide (omethoate) differs between the species. P. falcatus shows the highest LC₅₀, and may be responsible for pesticide control failures. Rearing methods for P. major and P. falcatus are described. The large differences between these blue oat mite species point to difficulties in interpreting early published data that failed to distinguish them.     

基于16S rDNA序列探讨十种臂尾轮虫的系统关系和分类地位

通过对角突臂尾轮虫、尾突臂尾轮虫、裂足臂尾轮虫、剪形臂尾轮虫、方形臂尾轮虫、壶状臂尾轮虫、红臂尾轮虫、镰肜臂尾轮虫、萼花臂尾轮虫和十指臂尾轮虫等十种臂尾轮虫和大肚须足轮虫的线粒体16s rDNA进行扩增和序列测序,结合Genebank 中十指臂尾轮虫的16S rDNA序列,使用MAGE软件构建了NJ(neighbor-joining method)树,使用mrbayes软件构建了贝叶斯树,探讨了十种臂尾轮虫之间的系统关系.结果表明,本研究所涉及的轮虫16S rDNA序列差异百分比均值为14.6%,可作为分子标记应用于轮虫属内种间系统关系研究;系统树均支持将十指臂尾轮虫、裂足臂尾轮虫隶属于臂尾轮属;壶状臂尾轮虫和红臂尾轮虫是两个独立的种.此外,还依据16S rDNA序列变异百分比推测了十种臂尾轮虫的分化时间.     

A new endemic focus of Heterophyes nocens and other heterophyid infections in a coastal area of Gangjin-gun, Jeollanam-do

To know the prevalence of heterophyid trematodes among inhabitants of a southern coastal village, i.e., Sacho-ri, Gangjin-gun, Jeollanam-do (Province), 82 stool samples were examined on helminth eggs and protozoan cysts using Kato-Katz and formalin-ether sedimentation techniques. Total 33 people (40.2%) were positive for trematodes (Heterophyes nocens 15 people, Pygidiopsis summa 3, Metagonimus sp.; 4, Clonorchis sinensis 7, Gymnophalloides seoi 6) and/or protozoa (Entamoeba coli 3). Among intestinal trematode egg positive cases, 17 were treated with praziquantel and their whole diarrheic stools were collected after purgation. Adult flukes of H. nocens (number of specimens = 1,294), P. summa (386), Stellantchasmus falcatus (5), Stictodora lari (4), and Heterophyopsis continua (1) were collected using a stereomicroscope. To know the source of human H. nocens infections in this village, metacercarial infections in mullets (10) were examined and most H. nocens metacercariae (101/105, 96.2%) were found in the trunk portion. From above results, the surveyed coastal village has been newly known as an endemic focus of human H. nocens infection and consuming raw mullets was the presumable source of human heterophyid infections.     

A revision of the millipede genus Riukiupeltis Verhoeff, 1939 (Diplopoda, Polydesmida, Paradoxosomatidae), with comments on the status of related species

The East Asian millipede genus Riukiupeltis Verhoeff, 1939 is revised, and is restricted to a single species, Riukiupeltis jamashinai Verhoeff, 1939. Examination of the type specimens and freshly collected material from the Ryukyu Archipelago and Vietnam show that both subsequently allocated species, Riukiupeltis uenoi Murakami, 1975, and Riukiupeltis falcatus (originally Haplogonosoma falcatum Attems, 1953, reallocated by Jeekel 1968), do not belong to this genus; moreover, they are not even congeneric with each other. According to our morphological observations, including the gonopods, Riukiupeltis uenoi is closer to the widespread Chamberlinius hualienensis Wang, 1956, hence we propose the new combination Chamberlinius uenoi (Murakami, 1975), comb. n.Riukiupeltis falcatus, on the other hand, represents a separate, as yet monotypic, genus Simplogonomorphagen. n., distinct both from Haplogonosoma Br?lemann, 1916 sensu Golovatch et al. (1995), and from Verhoeff's original Riukiupeltis. Additionally, Simplogonomorpha falcata (Attems, 1953), comb. n is re-described here based on fresh material from Vietnam. A key and colour habitus-illustrations to all three species are also provided here.     

Description of a new Echinorhynchid species (Acanthocephala) from the European eel, Anguilla anguilla, in Germany, with a key species of Acanthocephalus in Europe

Acanthocephalus rhinensis n. sp. is described from the European eel. Anguilla anguilla (Linnaeus, 1758), collected in the Rhine River near the city of Karlsruhe, Germany. It is the sixth species of Acanthocephalus Koelreuther, 1771 described from European fish. Four other species are known from amphibians. The new species is distinguished from the other 5 species infecting fish by having a 1.2-mm-long proboscis armed with 15-21 rows of 13-16 hooks each, lemnisci about as long as receptacle, oblong and slightly pre-equatorial testes, and thin fusiform eggs, measuring 85-95 X 15-18 micro. Testes in the other European species are usually round to ovate, except in Ac. anguillae (Müller, 1780) Lühe, 1911 where they are also elongated but postequatorial. It aslo has an orange-brown belt encircling the anterior end of the trunk. The comparative distribution of Acanthocephalus in Europe and North America, and the validity of 2 presumably questionable species are discussed, Acanthocephalus falcatus (Froelich, 1789) Lühe, 1911 and Ac. Paronai (Cendorelli, 1897) Meyer, 1932. A dichotomus key distinguishing Ac. rhinensis from the other 9 European species is also included. The new species was only found in 3 of 390 eels examined during 11 yr; this may be related to the changing benthos community in the Rhine River.     

Infection status with helminthes in feral cats purchased from a market in Busan, Republic of Korea

The present study was performed to investigate the infection status with helminth in a group of feral cats in Korea. More than 29 helminth species including adults or eggs were detected in visceral and fecal samples of the examined cats. Among these were a host of nematodes, including toxocarids, Ancylostoma sp. and the larva of Anisakis simplex; trematodes, including Clonorchis sinensis, Paragonimus westermani, Eurytrema pancreaticum, Pharyngostomum cordatum, Metagonimus spp., Heterophyes nocens, Pygidiopsis summa, Heterophyopsis continua, Stictodora fuscata, Stictodora lari, Acanthotrema felis, Stellantchasmus falcatus, Centrocestus armatus, Procerovum varium, Cryptocotyle sp., Echinostoma revolutum, Echinostoma hortense, Echinochasmus japonicus, Stephanoprora sp., Plagiorchis muris, Neodiplostomum sp. and diplostomulum. We also detected a variety of cestodes, including Spirometra erinacei, Taenia taeniaeformis and unidentified species of tapeworm. We also found examples of the acanthocephalan, Bolbosoma sp. In our assessment of the stools, we detected at least 12 species of helminth eggs. These findings confirmed that feral cats in Korea are infected with a variety of helminth parasite species. Furthermore, among the helminths detected, E. pancreaticum, S. fuscata, S. lari, A. felis, S. falcatus, C. armatus, P. varium, Cryptocotyle sp., E. revolutum, E. japonicus, Stephanoprora sp., P. muris, Neodiplostomum sp. and Bolbosoma sp. represent helminth fauna which have not been reported previously in feral cats in the Republic of Korea.     

Isolation and characterization of human and mouse ZIRTL, a member of the IRT1 family of transporters, mapping within the epidermal differentiation complex

We report the precise mapping and characterization of ZIRTL (zinc-iron regulated transporter-like) gene, the first mammalian member of an extensive family of divalent metal ion transporters, comprising IRT1 and ZIP1, ZIP2, ZIP3, and ZIP4 in plants and ZRT1 and ZRT2 in yeast. The human gene maps at the telomeric end of the epidermal differentiation complex (EDC), within chromosomal band 1q21, while the mouse gene maps within the mouse EDC, on mouse chromosome 3, between S100A9 and S100A13. The structure of the human gene has been determined, and message was detected in most adult and fetal tissues including the epidermis. The mouse gene is developmentally regulated and found expressed in fetal and adult suprabasal epidermis, osteoblasts, small intestine, and salivary gland.     

Rapid and simple identification of human pathogenic heterophyid intestinal fluke metacercariae by PCR-RFLP

Six species of heterophyid intestinal flukes (HIFs) constitute the major endemic zoonotic fish-borne pathogens in Asia: Haplorchis taichui, H. pumilio, H. yokogawai, Procerovum varium, Stellantchasmus falcatus, and Centrocestus formosanus. Several different species of these parasites are often found co-infecting the same second intermediate fish host. Because of their morphological similarities, differentiating between species of HIF metacercariae is difficult, time-consuming, and frequently results in misidentification. In this study, we aimed to develop an efficient and accurate method of identifying metacercariae of these 6 HIFs. Metacercariae were roughly grouped together, based on morphological characteristics seen under a stereomicroscope. Then, PCR-restriction fragment length polymorphism (PCR-RFLP) was used to identify the exact species of each metacercaria, using the 28S ribosomal RNA gene as the genetic marker and MboII as the restriction enzyme. Using a combination of morphological and molecular methods eliminates the need for DNA sequencing and infecting animal subjects to obtain adult worms, increases accuracy, and decreases the need for laborious morphological identification. Because the method is simple, rapid, and relatively cheap compared with PCR-sequencing, it may be an effective tool for epidemiological studies of HIFs in endemic areas.     

Plant host associations of Penthaleus species and Halotydeus destructor (Acari: Penthaleidae) and implications for integrated pest management

Integrated pest management programs seek to minimise reliance on pesticides and provide effective long-term control of pests. Cultural control strategies, such as crop rotations, trap and border crops, and weed management, require a thorough understanding of pest host associations. This paper examines the effects of different plant hosts on the persistence and reproduction of blue oat mites, Penthaleus spp., and the redlegged earth mite, Halotydeus destructor (Tucker), which are major agricultural pests in southern Australia. Field and shade-house experiments were conducted testing several crop and plant types. All species survived and reproduced from one mite season to the next when confined to pasture. Canola and a common weed, 'bristly ox-tongue', were suitable hosts for H. destructor and Penthaleus falcatus (Qin and Halliday), whereas Penthaleus sp. x and Penthaleus major (Dugés) failed to persist on these plants. A mixture of wheat and oats sustained P. sp. x and H. destructor, but not P. falcatus or P. major. Lentils were generally a poor host plant for all mite species. These findings show that earth mite species differ in their ability to persist on different plant types, highlighting the importance of distinguishing mite species before implementing control strategies. Results are discussed with respect to cultural control options for the management of these winter pests.     

应用胎儿特异性抗体HbF（γ链）标记法无创性 产前基因诊断DMD

以孕8~26周孕妇外周血为材料,经过Percoll密度梯度离心初步富集,胎儿细胞特异性抗体—HbF标记、识别胎儿有核红细胞,母体和胎儿有核红细胞的精确区分是以胎儿和成人血红蛋白的组成差异为基础的。胎儿细胞胞浆黄染,而具有成人血红蛋白的母体细胞没有颜色。显微操作法获取全部阳性细胞后,以其全基因组扩增（PEP）的产物为模板,进行性别检测、DMD基因的多重PCR检测和STR连锁分析。结果,20名孕妇外周血中均发现与HbF呈阳性反应的胎儿NRBC。并完成7例DMD的产前基因诊断。HbF抗体标记法能有效识别胎儿有核红细胞,是无创性产前基因诊断中很有应用前景的标记方法。 Abstract： Maternal blood was obtained at 8-26weeks of gestation.After discontinuous density gradient centrifugation with Percoll ,HbF antibody was used to identify fetal NRBC.The precise differentiation between fetal and maternal NRBC is based on the constitutional difference between fetal and adult hemoglobin (Hb).Fetal cells appear yellow cytoplasmic staining,while adult cells colorless. NRBCs were collected by micromanipulation andwhole genome amplification was performed. DMD was prenatally diagnosed by using the combination of sex determination,multiplex PCR and linkage analysis of several STR sites of dystrophin. NRBCs stained with HbF were found in all of 20 maternal blood samples with gestations, and 7 fetuses with risk of DMD were diagnosed. We concluded that HbF antibody could identify fetal NRBC efficaciously,and this is a kind of more prospective application method.     

Effects of praziquantel and artesunate on the tegument of adult Schistosoma mekongi harboured in mice

The effects of praziquantel and artesunate on the tegument of adult Schistosoma mekongi harboured in mice were compared using scanning electron microscopy (SEM). Forty-two mice infected with S. mekongi for 49 days were treated intragastrically with either 300 mg/kg praziquantel or 300 mg/kg artesunate. Mice were sacrificed 1 or 3 days post-treatment. Worms were collected by perfusion and examined by SEM. One to 3 days after administration of artesunate, the tegument of S. mekongi showed severe swelling, vacuolization, fusion of the tegumental ridges and loss or shortening of the spines on the trabeculae, collapse and peeling. Praziquantel induced similar tegumental alterations as those observed after administration of artesunate, but they were less severe. Three days post-treatment, there was evidence of recovery only in the case of praziquantel. The results of our study suggest that artesunate is more effective than praziquantel in causing tegumental damage in adult S. mekongi, and provides a basis for subsequent clinical trials.     

Prevalence of zoonotic trematodes in fish from a Vietnamese fish-farming community

The prevalence of fish-borne zoonotic trematode (FZT) metacercariae was investigated in fish farmed by rural households in Nghe An Province, located in northern Vietnam. In total, 716 fish, including tilapia (Oreochromis niloticus) and 6 carp species, i.e., grass carp (Ctenopharyngodon idellus), bighead carp (Aristichthys nobilis), mrigal (Cirrhinus mrigala), common carp (Cyprinus carpio), silver carp (Hypophthalmychthys molitrix), and roha (Labeo rohita), collected from 53 fish farms were examined. The overall prevalence of FZT metacercariae was 44.6%, ranging from 12.5% to 61.0% in fish species collected from grow-out ponds, which are the production system for growing fish from fingerling size to market size. The overall prevalence was 43.6% in fingerlings cultured in nurseries, ranging from 7.4% to 62.8% for different fish species. The FZT species recovered were heterophyids and echinostomatids and included Haplorchis pumilio, H. taichui, H. yokogawai, Centrocestus formosanus, Stellantchas musfalcatus, and Echinochasmus japonicus, all of which are intestinal flukes in humans, other mammals, and birds. This is the first report of H. yokogawai and E. japonicus in fish in Vietnam, and the first record for S. falcatus in northern Vietnam. Although a previous cross-sectional survey of the people living in these fish farm households revealed a very low prevalence of FZTs (< 1%), our results demonstrate that intestinal flukes are common in farmed fish in this area, suggesting that reservoir hosts such as dogs, cats, and pigs are more important in sustaining the life cycles of these flukes in fish farms than human hosts. This has implications for the effectiveness of control programs focused mainly on treatment of humans.     

Intrauterine contraceptive device-associated pelvic actinomycosis caused by Actinomyces urogenitalis

We report a case of intrauterine contraceptive device (IUD) associated pelvic actinomycosis due to Actinomyces urogenitalis in a previously healthy young adult woman. Diagnosis was confirmed by 16S ribosomal RNA gene sequencing of bacterial colonies growing from the extracted device. This is the first documented report of human infection caused by this micro-organism.     

Comparison of cranial ontogenetic trajectories among great apes and humans

Molecular data suggest that humans are more closely related to chimpanzees than either is to the gorillas, yet one finds the closest similarity in craniofacial morphology to be among the great apes to the exclusion of humans. To clarify how and when these differences arise in ontogeny, we studied ontogenetic trajectories for Homo sapiens, Pan paniscus, Pan troglodytes, Gorilla gorilla and Pongo pygmaeus. A total of 96 traditional three-dimensional landmarks and semilandmarks on the face and cranial base were collected on 268 adult and sub-adult crania for a geometric morphometric analysis. The ontogenetic trajectories are compared by various techniques, including a new method, relative warps in size-shape space. We find that adult Homo sapiens specimens are clearly separated from the great apes in shape space and size-shape space. Around birth, Homo sapiens infants are already markedly different from the great apes, which overlap at this age but diverge among themselves postnatally. The results suggest that the small genetic differences between Homo and Pan affect early human ontogeny to induce the distinct adult human craniofacial morphology. Pure heterochrony does not sufficiently explain the human craniofacial morphology nor the differences among the African apes.     

The life cycle of Monorchis parvus (Digenea: Monorchiidae) demonstrated by developmental and molecular data

Cercaria cerastodermae I, a digenean parasite of Cerastoderma edule, was recorded for the first time in the Atlantic Ocean off the Iberian peninsula. Sporocysts were present in the hemolymph of the digestive gland, gonad, gills, and foot of the mollusc. Most of the cercariae present within sporocysts were encysted as metacercariae. The corresponding adult stages were obtained after experimental infection of several Diplodus sargus artificially reared in fish farms and that had previously been protected against natural infections. Numerous adult specimens of Monorchis parvus were collected in Diplodus annularis along the French Mediterranean coast. Comparison of wild and experimental adults allowed the adult stage of Cercaria cerastodermae I to be identified as M. parvus. Another monorchid, Monorchis monorchis, a parasite of Spondyliosoma cantharus, was found in the same Mediterranean area and compared with M. parvus. Additionally, ITS1 nuclear ribosomal DNA sequences of C. cerastodermae I and of the adults collected in naturally infected D. annularis and S. cantharus were obtained. Sequence data indicate that C. cerastodermae I corresponds to the adult of M. parvus found in D. annularis and is clearly distinct from M. monorchis found in S. cantharus.