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trichobilharzia regenti n. sp. (schistosomatidae, bilharziellinae), a new nasal schistosome from europe.members of the genus trichobilharzia are parasitic in visceral or nasal body parts of their avian hosts. the examination of water snails in south bohemia revealed a schistosome infection in radix peregra snails. the experimental infection of ducklings (anas platyrhynchos, cairina moschata) confirmed that a new trichobilharzia species--t. regenti n. sp.--was found. the adults, eggs and larvae (miracidia and cercariae) of the species were morphologically characterized. the adult occupy the nasal b ...19989879557
trichobilharzia regenti, a pathogen of the avian and mammalian central nervous systems.the development of nasal avian schistosomes of the genus trichobilharzia in their final host is poorly known. therefore, an experimental infection of ducklings (anas platyrhynchos f. dom.) by t. regenti was performed. the infection resulted in leg paralysis and orientation/balance disorders of birds. the examination of the duck's spinal cord and brain confirmed the presence of developing parasites in pre-patent as well as patent periods. the absence of the worms in other tissues strongly support ...199910633919
the karyotype of trichobilharzia regenti horák, kolárová et dvorák, 1998 (digenea: schistosomatidae), a nasal avian schistome in central europe.the karyotype of a european bird nasal schistosome, trichobilharzia regenti horák, kolárová et dvofák, 1998, was determined. the chromosome set comprises eight pairs, seven of which are autosomes and one sex pair consisting of zz in males and zw in females. the z is the largest chromosome of the set, having a submeta-metacentric location of centromere, while the w is a small metacentric chromosome. more than 60% of the analyzed cells originating from both male and female sporocysts contained one ...200111411949
histopathology of cns and nasal infections caused by trichobilharzia regenti in vertebrates.in bird infections caused by trichobilharzia regenti, the central nervous system (cns) represents probably the main route to the nasal cavity, where maturation of the parasite occurs. however, in an abnormal mouse host, development is incomplete and is accompanied by a strong affinity of the parasite to the cns. in order to explain pathological changes caused by the parasite, a histological study of cross-sections from the cns and nasal cavity was performed. in the cns of duck and mouse, immatur ...200111511002
genetic variability among cercariae of the schistosomatidae (trematoda: digenea) causing swimmer's itch in europe.ribosomal dna sequences of the internal transcribed spacer 1 (its1) were obtained from schistosome cercariae responsible for swimmer's itch in europe. two types of its1 (1100 and 1400), which differ by the number of repeated patterns were found among cercariae shedded by lymnaea ovata and l. auricularia (lymnaeidae). a phylogenetic analysis of the its1 region showed that sequences of each type form two well-defined clades. an adult of trichobilharzia regenti isolated from the nasal vessels of an ...200111584754
neurotropic behaviour of trichobilharzia regenti in ducks and mice.the bird nasal schistosome trichobilharzia regenti is a new agent of cercarial dermatitis. cercariae are able to penetrate the skin of birds and mammals including man. the parasite then attacks the central nervous system. the present study has shown that schistosomula avoid penetration of blood capillaries and enter the peripheral nerves of the legs of mice and ducks as early as 1 day post-infection (p.i.) and 1.5 days p.i., respectively. these peripheral nerves are used as a route to the spinal ...200212015826
variations in immunofluorescent antibody response against trichobilharzia and schistosoma antigens in compatible and incompatible hosts.schistosome cercariae are able to penetrate into the skin of various vertebrate hosts. however, in contrast to the compatible host, the infection of incompatible hosts results in the death of parasites at various intervals post-infection. in order to compare the immune responses in both types of host infected with trichobilharzia regenti, trichobilharzia szidatior schistosoma mansoni, antibody responses against various t. regenti, t. szidatiand s. mansonischistosome developmental stages were stu ...200212107473
detection of bird schistosomes in lakes by pcr and filter-hybridization.many lakes around the world are contaminated with bird schistosome cercariae, which penetrate into human skin, causing an itching dermatitis called "swimmers' itch." bathers could be forewarned from exposure to the larvae and ecological examinations could be performed, when a sensitive method to detect the parasites in aquatic systems, where lots of organisms hinder microscopic examinations, would be available. for this purpose we cloned, sequenced, and analyzed a 396 bp tandem repeated dna sequ ...200212243738
cercarial dermatitis caused by bird schistosomes comprises both immediate and late phase cutaneous hypersensitivity reactions.avian schistosomes are the primary causative agent of cercarial dermatitis in humans, but despite its worldwide occurrence, little is known of the immune mechanism of this disease. using a murine model, hosts were exposed to primary (1x) and multiple (4x) infections of trichobilharzia regenti via the pinna. penetration of larvae into the skin evoked immediate edema, thickening of the exposure site, and an influx of leukocytes, including neutrophils, macrophages, cd4+ lymphocytes, and mast cells. ...200415004181
the severity of mouse pathologies caused by the bird schistosome trichobilharzia regenti in relation to host immune status.cercariae of the nasal bird schistosome trichobilharzia regenti are able to penetrate into mammalian skin and migrate to the mouse central nervous system (cns) causing tissue injury in certain cases. our study shows that the severity of t. regenti pathologies in the cns closely depends on the host immune status. during the primary infection of immunocompetent mice, the parasites evoked an acute inflammatory reaction in the skin and the cns involving focal oedema and cellular infiltration of the ...200415034785
trichobilharzia regenti: the developmental differences in natural and abnormal hosts.trichobilharzia regenti is a bird nasal parasite causing human cercarial dermatitis. schistosomula are able to migrate via the bird nervous system and then, they mature and lay eggs in the nasal cavity. to some extent they can also migrate and develop in mammals. the present study has shown the developmental differences of t. regenti in the natural (ducks) and the abnormal (mice; inbred strains balb/c, scid) hosts. the study describes the following parameters of developing worms: length and widt ...200515908263
multiple cathepsin b isoforms in schistosomula of trichobilharzia regenti: identification, characterisation and putative role in migration and nutrition.among schistosomatids, trichobilharzia regenti, displays an unusual migration through the peripheral and central nervous system prior to residence in the nasal cavity of the definitive avian host. migration causes tissue degradation and neuromotor dysfunction both in birds and experimentally infected mice. although schistosomula have a well-developed gut, the peptidases elaborated that might facilitate nutrition and migration are unknown. this is, in large part, due to the difficulty in isolatin ...200515950230
comparison of cysteine peptidase activities in trichobilharzia regenti and schistosoma mansoni cercariae.cercariae of the bird schistosome trichobilharzia regenti and of the human schistosome schistosoma mansoni employ proteases to invade the skin of their definitive hosts. to investigate whether a similar proteolytic mechanism is used by both species, cercarial extracts of t. regenti and s. mansoni were biochemically characterized, with the primary focus on cysteine peptidases. a similar pattern of cysteine peptidase activities was detected by zymography of cercarial extracts and their chromatogra ...200717517170
the complete mitochondrial genome of the bird schistosome trichobilharzia regenti (platyhelminthes: digenea), causative agent of cercarial dermatitis.the complete mitochondrial (mt) genome of the neuropathogenic bird schistosome trichobilharzia regenti was fully sequenced in order to develop molecular markers for future diagnostic, molecular ecological, population, and phylogenetic studies. the genome was 14,838 bp in length, with a 68.4% at bias in protein coding regions. a repeat element (3 x 184 bp) between trnv and trnw distinguished a single short noncoding region. as 9 of 14 genera of schistosomes parasitize birds, future characterizati ...200717626347
bird schistosomes of wildfowl in the czech republic and poland.in 2005, we dissected 102 wildfowl from the czech republic and 73 wildfowl from poland including representatives of anseriformes, gruiformes and gaviiformes. schistosome infection was found in a total of 21 (29%) and 23 (23%) birds from poland and the czech republic, respectively. all infected birds belonged to the order anseriformes. the prevalences of nasal and visceral species were, respectively, 22% and 16% in poland and 6% and 19% in the czech republic. four species of schistosomes were fou ...200717886736
peptidases of trichobilharzia regenti (schistosomatidae) and its molluscan host radix peregra s. lat. (lymnaeidae): construction and screening of cdna library from intramolluscan stages of the parasite.trichobilharzia regenti is a neurotropic bird schistosome,causing cercarial dermatitis in humans. in this study, zap cdna expression library from radix peregra s. lat. hepatopancreases containing intramolluscan stages of t. regenti was constructed and screened using pcr with specific and degenerate primers, designed according to previously described serine and cysteine peptidases of other parasite species. full-length sequences of cathepsins b1 and l, and two serine peptidases, named rpsp1 and r ...200717886737
terminal phase of bird schistosomiasis caused by trichobilharzia regenti (schistosomatidae) in ducks (anas platyrhynchos f. domestica).the terminal phase of the migration of trichobilharzia regenti horák, kolárová et dvorák, 1998 in the definitive host (anas platyrhynchos f. domestica) was studied 12-27 days post infection (p.i.). brain meninges were the last part of the nervous system where the worms were detected before their occurrence in the nasal cavity. in meninges, the parasites started to feed on red blood cells. then the worms occurred in the nasal mucosa 14-25 days p.i. and the first immature eggs appeared 15 days p.i ...200717886739
trichobilharzia spp. in natural conditions in annecy lake, france.annecy lake is a well-known focus of human cercarial dermatitis in france. identification of the parasites, however, was not performed in the past. previous studies suspected two species, trichobilharzia franki and trichobilharzia regenti, based on the presence of parasites in mallards and/or morphological identification of snails emitting ocellate furcocercariae. following a standardized molecular approach, we studied snails and furcocercariae and compared their haplotypes with those deposited ...200818320223
the functional expression and characterisation of a cysteine peptidase from the invasive stage of the neuropathogenic schistosome trichobilharzia regenti.a transcriptional product of a gene encoding cathepsin b-like peptidase in the bird schistosome trichobilharzia regenti was identified and cloned. the enzyme was named trcb2 due to its 77% sequence similarity to cathepsin b2 from the important human parasite schistosoma mansoni. the zymogen was expressed in the methylotropic yeast pichia pastoris; procathepsin b2 underwent self-processing in yeast media. the peptidolytic activity of the recombinant enzyme was characterised using synthetic fluoro ...200918708063
antibody responses induced by trichobilharzia regenti antigens in murine and human hosts exhibiting cercarial dermatitis.cercariae of bird schistosomes (genus trichobilharzia) are able to penetrate the skin of mammals (noncompatible hosts), including humans, and cause a th2-associated inflammatory cutaneous reaction termed cercarial dermatitis. the present study measured the antibody reactivity and antigen specificity of sera obtained after experimental infection of mice and natural infection of humans. sera from mice re-infected with t. regenti showed a bias towards the development of antigen-specific igm and igg ...200819067839
in vitro cultivation of early schistosomula of nasal and visceral bird schistosomes (trichobilharzia spp., schistosomatidae).cercariae of bird schistosomes (trichobilharzia szidati and trichobilharzia regenti) were mechanically stimulated to transform to schistosomula and kept in different cultivation media supplemented with duck red blood cells and/or homogenized nervous tissue. the development under in vitro conditions was compared with that in vivo, using the following characters: emptying of penetration glands, surface changes, food uptake, and growth of early schistosomula. the results show that the cultivation m ...200919238442
avian schistosomes in french aquatic birds: a molecular approach.the prevalence of human cercarial dermatitis (hcd) caused by bird schistosomes appears to be increasing in france, in light of the impact of tourism combined with high densities of wild aquatic hosts in freshwater areas. the present work expands our knowledge of schistosome systematics by including samples of bird schistosomes collected from their natural hosts in france. heads (318) and viscera (81) of aquatic birds belonging to 16 species from five orders, collecting during the hunting seasons ...200919356266
final hosts and variability of trichobilharzia regenti under natural conditions.in europe, despite of intensive work on avian schistosomes in the past, only one representative of nasal schistosomes has been detected so far, trichobilharzia regenti, a species that remained undescribed to the scientific community until 1998. since then, however, t. regenti has gained a considerable attention, not only due to the induction of serious lesions concomitant with the migration of the schistosomulae through the central nervous system of their natural hosts (birds) but also due to th ...201020556426
cathepsins b1 and b2 in the neuropathogenic schistosome trichobilharzia regenti: distinct gene expression profiles and presumptive roles throughout the life cycle.the neurotropic bird schistosome trichobilharzia regenti possesses papain-like cysteine peptidases which have also been shown to be crucial enzymes in various developmental stages of the related human parasites schistosoma spp. in this paper, we present data obtained by real-time polymerase chain reaction on the temporal distribution of transcripts of two cathepsins in different developmental stages of t. regenti: cathepsin b1 originally described from the gut lumen of schistosomula with presump ...201020556428
detection of european trichobilharzia schistosomes ( t. franki , t. szidati , and t. regenti ) based on novel genome sequences.the most frequent causative agents of cercarial dermatitis in europe are the avian schistosomes of the genus trichobilharzia . they preferably parasitize birds of the anatidae. trichobilharzia spp. schistosomes are also able to penetrate mammalian skin, posing a health risk to mammals, including humans. currently several loci from nuclear and mitochondrial genomes are determined for european species of trichobilharzia . among them there is 1 genome sequence, tosau3a, which is suitable for detect ...201020677938
trichobilharzia regenti (digenea: schistosomatidae): changes of body wall musculature during the development from miracidium to adult worm.trichobilharzia regenti (schistosomatidae, digenea), a parasite of birds, exhibits a unique strategy among schistosomes, having affinity to the nervous system of vertebrate hosts. migration of parasitic stages within hosts and/or swimming of non-parasitic larvae in water environment depend on the action of body wall muscles which were studied with confocal and electron microscopy. in all stages, body wall musculature is comprised of differently organized circular and longitudinal muscles. during ...201120813538
trichobilharzia regenti: host immune response in the pathogenesis of neuroinfection in mice.besides their natural bird hosts, trichobilharzia regenti cercariae are able to penetrate skin of mammals, including humans. experimental infections of mice showed that schistosomula of this species are able to avoid the immune response in skin of their non-specific mammalian host and escape the skin to migrate to the cns. schistosomula do not mature in mammals, but can survive in nervous tissue for several days post infection. neuroinfections of specific bird hosts as well as accidental mammali ...201121554878
cathepsins b1 and b2 of trichobilharzia spp., bird schistosomes causing cercarial dermatitis.trichobilharzia regenti and t. szidati are schistosomes that infect birds. although t. regenti/t. szidati can only complete their life cycle in specific bird hosts (waterfowl), their larvae-cercariae are able to penetrate, transform and then migrate as schistosomula in nonspecific hosts (e.g., mouse, man). peptidases are among the key molecules produced by these schistosomes that enable parasite invasion and survival within the host and include cysteine peptidases such as cathepsins b1 and b2. t ...201121660663
proteomic analysis of human skin treated with larval schistosome peptidases reveals distinct invasion strategies among species of blood flukes.skin invasion is the initial step in infection of the human host by schistosome blood flukes. schistosome larvae have the remarkable ability to overcome the physical and biochemical barriers present in skin in the absence of any mechanical trauma. while a serine peptidase with activity against insoluble elastin appears to be essential for this process in one species of schistosomes, schistosoma mansoni, it is unknown whether other schistosome species use the same peptidase to facilitate entry in ...201121980548
secretory glands in cercaria of the neuropathogenic schistosome trichobilharzia regenti - ultrastructural characterization, 3-d modelling, volume and ph estimations.cercariae of schistosomes employ bioactive molecules for penetration into their hosts. these are released from specialized unicellular glands upon stimuli from host skin. the glands were previously well-described in the human pathogen schistosoma mansoni. as bird schistosomes can also penetrate human skin and cause cercarial dermatitis, our aim was to characterize the architecture and ultrastructure of glands in the neurotropic bird schistosome trichobilharzia regenti and compare it with s. mans ...201121854564
morphological features of the nasal blood fluke trichobilharzia regenti (schistosomatidae, digenea) from naturally infected hosts.the first author detected the nasal bird schistosome trichobilharzia regenti in iceland in anas platyrhynchos in landmannalaugar in autumn of 2003. since then, measurements and morphological studies have been performed on fresh worms (fragments) obtained in the area from naturally infected ducks, a. platyrhynchos and aythya marila. in the present study, we compare our findings to the original description of t. regenti by horák et al. (parasite 5:349-357, 1998) that relies upon worms obtained by ...201122146993
species identification of birds nasal trichobilharzia in sari, north of iran.cercarial dermatitis is known as an endemic parasitic disease in north of iran, a hypersensitive skin reaction to the penetration of nonhuman schistosome larvae into human skin. in recent studies in this region, final and intermediate hosts were recognized and trichobilharzia was identified as the main causative agent of cercarial dermatitis in this region, but to date the parasite species haven't been identified. therefore this study was performed to species identification of nasal trichobilhar ...201223323095
having bird schistosomes in mind-the first detection of bilharziella polonica (kowalewski 1895) in the bird neural system.nasal bird schistosomes can cause bilharziosis in birds and have the potential to cause swimmer's itch in humans. we determined the prevalence of bird schistosomes in 106 mallards (anas plathyrhynchos) from 11 water sources in germany from 2014. dissections were performed focusing on parasitic infections of the neural system. infections with trichobilharzia regenti (horák et al. 1998) were found in 21% of the birds (n = 22), whereas bilharziella polonica (kowalewski 1895) were found between the ...201728012027
radix spp.: identification of trematode intermediate hosts in the czech republic.lymnaeid snails of the genus radix serve as intermediate hosts of some schistosomes and fasciolids. in europe, delineation of species within the genus radix is unresolved and, therefore, spectrum of snail hosts susceptible to trematode infections is under discussion. we used and compared three criteria for species delineation using snails collected at 43 localities. (a) sequence analysis of its-2 rdna disclosed that the collected snails belong to four species - r. auricularia (linnaeus, 1758), r ...201222875675
molecular diversity of avian schistosomes in danish freshwater snails.avian schistosomes are widespread parasites of snails and waterfowl and may cause cercarial dermatitis (swimmer's itch) in humans, a disease that is frequently reported in european countries. these parasites are known to occur in denmark, but here, we applied a new approach using molecular tools to identify the parasites at species level. in order to do that, 499 pulmonate freshwater snails (radix sp., lymnaea stagnalis, stagnicola sp. and planorbarius corneus) were sampled from 12 lakes, ponds, ...201626573519
changes in surface glycosylation and glycocalyx shedding in trichobilharzia regenti (schistosomatidae) during the transformation of cercaria to schistosomulum.the invasive larvae (cercariae) of schistosomes penetrate the skin of their definitive hosts. during the invasion, they undergo dramatic ultrastructural and physiological transitions. these changes result in the development of the subsequent stage, schistosomulum, which migrates through host tissues in close contact with host's immune system. one of the striking changes in the transforming cercariae is the shedding of their thick tegumental glycocalyx, which represents an immunoattractive struct ...201728296924
nitric oxide and cytokine production by glial cells exposed in vitro to neuropathogenic schistosome trichobilharzia regenti.helminth neuroinfections represent a serious health problem, but host immune mechanisms in the nervous tissue often remain undiscovered. this study aims at in vitro characterization of the response of murine astrocytes and microglia exposed to trichobilharzia regenti which is a neuropathogenic schistosome migrating through the central nervous system of vertebrate hosts. trichobilharzia regenti infects birds and mammals in which it may cause severe neuromotor impairment. this study was focused on ...201627842570
impact of induced th1/th2 shift on trichobilharzia regenti infection in mice.bird schistosomes parasitize mammals as non-specific hosts. neurotropic trichobilharzia regenti migrates extravasally via nervous tissue in experimentally infected mice. the majority of successfully penetrated larvae remain in the skin; the rest migrate through peripheral nerves to the spinal cord and brain. the potential of schistosomula to leave the skin and enter the central nervous system vary, and may be associated with th1/th2 polarization of the host cell immune response. the aim of the p ...201627085007
trichobilharzia regenti (schistosomatidae): 3d imaging techniques in characterization of larval migration through the cns of vertebrates.migration of parasitic worms through the host tissues, which may occasionally result in fatal damage to the internal organs, represents one of the major risks associated with helminthoses. in order to track the parasites, traditionally used 2d imaging techniques such as histology or squash preparation do not always provide sufficient data to describe worm location/behavior in the host. on the other hand, 3d imaging methods are widely used in cell biology, medical radiology, osteology or cancer r ...201626897588
comparative transcriptomic exploration reveals unique molecular adaptations of neuropathogenic trichobilharzia to invade and parasitize its avian definitive host.to date, most molecular investigations of schistosomatids have focused principally on blood flukes (schistosomes) of humans. despite the clinical importance of cercarial dermatitis in humans caused by trichobilharzia regenti and the serious neuropathologic disease that this parasite causes in its permissive avian hosts and accidental mammalian hosts, almost nothing is known about the molecular aspects of how this fluke invades its hosts, migrates in host tissues and how it interacts with its hos ...201626863542
phylogenetic analysis of nasal avian schistosomes (trichobilharzia) from aquatic birds in mazandaran province, northern iran.nasal schistosomes are trematodes in the family schistosomatidae, many members of which are causative agents of human cercarial dermatitis (hcd). little is known about the species diversity and distribution of nasal dwelling schistosomes of water birds, particularly in countries outside of europe; even less is known in countries like iran. nasal schistosomes are of particular interest since these species migrate via the central nervous system to the nasal cavity once they penetrate their host. t ...201626631753
antibody response of definitive hosts against antigens of two life stages of the neuropathogenic schistosome trichobilharzia regenti.the nasal avian schistosome trichobilharzia regenti spends part of its intravertebrate period of life within the central nervous system. migration of the parasites can be accompanied by neuromotor disorders or paralysis in natural definitive hosts (ducks) and even in laboratory mammals. cercariae are also able to penetrate human skin and induce cercarial dermatitis. while the cellular and antibody responses against cercariae and migrating schistosomula have been investigated in mice, little is k ...201526216102
trichobilharzia anseri n. sp. (schistosomatidae: digenea), a new visceral species of avian schistosomes isolated from greylag goose (anser anser l.) in iceland and france.parasitological investigations carried out on birds in iceland and france highlight the presence of four species of avian schistosomes from greylag geese (anser anser l.): the european nasal species trichobilharzia regenti and three visceral species, among which an unknown species isolated from blood vessels of the large intestine and liver. morphological and molecular analyzes of different parasite stages (eggs, adults) revealed new species of trichobilharzia genus – trichobilharzia anseri sp. ...201526070888
influence of trichobilharzia regenti (digenea: schistosomatidae) on the defence activity of radix lagotis (lymnaeidae) haemocytes.radix lagotis is an intermediate snail host of the nasal bird schistosome trichobilharzia regenti. changes in defence responses in infected snails that might be related to host-parasite compatibility are not known. this study therefore aimed to characterize r. lagotis haemocyte defence mechanisms and determine the extent to which they are modulated by t. regenti. histological observations of r. lagotis infected with t. regenti revealed that early phases of infection were accompanied by haemocyte ...201425372492
pathogenicity of trichobilharzia spp. for vertebrates.bird schistosomes, besides being responsible for bird schistosomiasis, are known as causative agents of cercarial dermatitis. cercarial dermatitis develops after repeated contact with cercariae, mainly of the genus trichobilharzia, and was described as a type i, immediate hypersensitivity response, followed by a late phase reaction. the immune response is th2 polarized. primary infection leads to an inflammatory reaction that is insufficient to eliminate the schistosomes and schistosomula may co ...201223125918
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