Showing papers in "Folia Parasitologica in 2003"
TL;DR: This review describes some of the history, recent findings, epidemiology, potential vectors, and the search for possible reservoir hosts besides man in Leishmania tropica.
Abstract: Leishmania tropica is one of the causative agents of cutaneous leishmaniasis (CL), a disfiguring parasitic disease that recently was found to be viscerotropic. In urban areas it is transmitted from infected individuals by the bite of phlebotomine sand flies to naive persons (anthroponotic CL). In rural areas animals are thought to be the reservoir, but the full life cycle is still under investigation (zoonotic CL). For many years L. tropica was either confused or merely grouped with L. major while Phlebotomus sergenti was the only proven vector. In recent years new foci have erupted, but few have been investigated. This review describes some of the history, recent findings, epidemiology, potential vectors, and the search for possible reservoir hosts besides man.
85 citations
TL;DR: It was found that G. africana has three larval stages, consisting of three unfed (zuphea) and three fed (praniza) stages, and the sex of the third and final praniza stage could be determined by the presence of either a testis or two ovaries in the dorsal pereon.
Abstract: Laboratory work was conducted to elucidate the life cycle of the South African gnathiid isopod, Gnathia africana Barnard, 1914. The natural fish hosts of this temporary parasite, the super klipfish Clinus superciliosus (Linnaeus, 1758), were exposed to gnathiid larvae in the laboratory. It was found that G. africana has three larval stages, consisting of three unfed (zuphea) and three fed (praniza) stages. First-, second- and third-stage zuphea larvae took an average of 2 h 18 min, 2 h 43 min and 10 h 8 min respectively to complete their feeding and the first- and second-stage praniza moulted at 8 and 10 days respectively into the next zuphea stage. Three to six days after its last blood meal, the sex of the third and final praniza stage could be determined by the presence of either a testis or two ovaries in the dorsal pereon. Male larvae moulted into adult males between 8 and 10 days post feeding. Female larvae moulted at approximately 17 days into adult females. Fertilisation of the eggs by the male took place within 24 hours of completion of the female moult. The development of the embryos and subsequent release of the young larvae between 15 and 23 days post fertilisation completed the cycle. This entire cycle took approximately 62 days in water temperatures of 20-25°C.
73 citations
TL;DR: A new species of amphizoic amoeba, Nuclearia pattersoni sp.
Abstract: A new species of amphizoic amoeba, Nuclearia pattersoni sp. n., isolated from gills of Rutilus rutilus L. is described. It is characterised by elongate flattened trophozoites of irregular shape. The longer dimension of their bodies is 13.2 (11.0-15.7) µm. Filopodia radiating mostly from the poles are 2 to 2.5 times longer than the body. The diameter of less frequently observed spherical trophozoites is 8.2-10.8 µm; their filopodia radiate to all directions. Cyst-like stages have shorter pseudopodia that arise from one pole only. The surface of locomotive forms from agar plate cultures has a thin amorphous glycocalyx, while most cells are covered by two layers of extracellular matrix. Mitochondria have flattened cristae, dictyosomes are located in the perinuclear zone. A conspicuous ultrastructural feature of the morphologically similar N. simplex, perinuclear striated band, is not present. Light microscopic and ultrastructural data are completed with the sequence of SSU rRNA gene and phylogenetic analysis including sequences of related taxa. The bacterial endosymbiont found in N. pattersoni type strain RR2G2 is assigned to the genus Rickettsia.
55 citations
TL;DR: All the results provide evidence for significant differences between the strains and further provided the basis for reclassification of the isolates, and implications in the clinical diagnosis of pathogenic Acanthamoeba are discussed.
Abstract: The genus Acanthamoeba includes more than 20 morphological species, but classification is problematical. Recently, the discovery of substantial interstrain differences in ribosomal DNA (rDNA) sequences has prompted questions about the relatedness of strains of the same species. In this study, therefore, we have investigated relationships between two isolates of A. polyphaga, CCAP 1501/3c and ATCC 30871, using morphological, biochemical, physiological, molecular and cytotoxicity assays. We observed that A. polyphaga ATCC 30871 exhibited up to six arms in endocyst while A. polyphaga CCAP 1501/3c exhibited a maximum of 5 arms thus indicating their position in group 2 and 3, respectively. Acanthamoeba polyphaga ATCC 30871 exhibited growth at 37°C and growth on 1M mannitol plates while A. polyphaga CCAP 1501/3c did not. In addition, both isolates exhibited differences in isoenzyme banding patterns and rDNA restriction fragment polymorphisms. More importantly, A. polyphaga ATCC 30871 produced cytotoxicity on corneal epithelial cells while A. polyphaga CCAP 1501/3c had no effects, suggesting differences in pathogenicity. Thus, all the results provide evidence for significant differences between the strains and further provided the basis for reclassification of the isolates. Implications of these results in the clinical diagnosis of pathogenic Acanthamoeba are discussed.
47 citations
TL;DR: Nitazoxanide (NTZ) was compared for curative activity with sinefungin (SNF) and paromomycin (PRM) in immunosuppressed rats, a screening model for anticryptosporidial agents and shedding inhibition was unchanged in NTZ-treated rats.
Abstract: Cryptosporidium parvum, Tyzzer, 1912 is identified as a common cause of diarrhoea in immunocompetent individuals. In immunocompromised, especially HIV-infected subjects, cryptosporidiosis causes severe chronic diarrhoea. In this study, nitazoxanide (NTZ) was compared for curative activity with sinefungin (SNF) and paromomycin (PRM) in immunosuppressed rats, a screening model for anticryptosporidial agents. NTZ at either 50 mg/kg/day, 100 mg/kg/day or 200 mg/kg/day resulted in seven days in a dose-dependent inhibition of oocyst shedding similar to that obtained with SNF (10 mg/kg/day) and PRM (100 mg/kg/day). Further discontinuation of SNF or PRM 100 mg/kg/day therapy resulted in early relapse of oocyst shedding which reached the pre-treatment levels in 2-4 days. In contrast, seven days after discontinuation of therapy, shedding inhibition was unchanged in NTZ-treated rats. Data prompt further assessment of the activity of NTZ on sequestered C. parvum.
46 citations
TL;DR: It is demonstrated that progenetic Archigetes sieboldi shares characteristics of both larval (progenetic) and adult stages and it is postulated that a similar process of progenesis may have played a major role in the early evolution of the Caryophyllidea by first appearing in a plerocercoid stage of an ancestral strobilate cestode from fish.
Abstract: Ultrastructural characteristics of progenetic and monoxenic Archigetes sieboldi Leuckart, 1878 from the oligochaete Limnodrilus hoffmeisteri Claparede are described. Our observations demonstrate that progenetic Archigetes sieboldi shares characteristics of both larval (progenetic) and adult stages. The primary larval characteristics are: the presence of a cercomer; a surface filamentous coat covering the whole worm; the presence of the penetration glands and the absence of tegumental ones; wide sarcoplasmic processes connecting the circular and longitudinal external tegumental muscles; the absence of the dense homogenous zone of the basal lamina beneath the epithelial cytoplasm of all reproductive organs and ducts; non-functional gonopores; and an orthogonal plan of nervous system with three pairs of longitudinal nerve trunks. The principle adult characteristics are: oogenesis, spermiogenesis and vitellogenesis that produce fertilized eggs; the uterine glands; a well-developed longitudinal tegumental muscle layer between tegumental cytons; and the presence of different microtriches. As a result of this progenetic development there has been a secondary reduction in the life cycle of A. sieboldi. It is postulated that a similar process of progenesis may have played a major role in the early evolution of the Caryophyllidea by first appearing in a plerocercoid stage of an ancestral strobilate cestode from fish.
45 citations
TL;DR: Seasonal samples of all fish species from Lake Moreno were taken to determine the presence of paratenia, to evaluate the status of the hosts and to characterise the transmission of Acanthocephalus tumescens at the component population level.
Abstract: Seasonal samples of all fish species from Lake Moreno were taken in order to determine the presence of paratenia, to evaluate the status of the hosts and to characterise the transmission of Acanthocephalus tumescens (von Linstow, 1896) at the component population level. Prevalence, mean abundance, mean intensity, numbers of gravid females, relative abundance of the different fish species, relative output of eggs and relative flow rates for each host species were computed. Acanthocephalus tumescens showed low host specificity, successfully parasitizing six out of eight fish species present in the lake. No paratenic infection was registered. If prevalence, mean abundance, and number of gravid females are considered, host species can be placed in a continuum from the most to least suitable as follows: Galaxias platei Steindachner, Diplomystes viedmensis (Mac Donagh), Oncorhynchus mykiss (Walbaum), Salvelinus fontinalis (Mitchill), Percichthys trucha (Cuvier et Valenciennes) and Galaxias maculatus (Jenyns). However, when parasite flow rates and egg output were calculated, including relative abundance of each fish species, the continuum was rearranged as follows: P. trucha, O. mykiss, G. platei / G. maculatus, S. fontinalis and D. viedmensis. The first four species would be the main contributors to the population of A. tumescens in this lake, P. trucha being the major one. Different regulatory and non-regulatory mechanisms are suggested.
45 citations
TL;DR: A systematic survey of nematodes based on helminthological examinations of 176 specimens of freshwater fishes from central China collected during the autumn of 2001, finding the finding of larval Eustrongylides in Paramisgurnus dabryanus represents a new host record.
Abstract: The present paper comprises a systematic survey of nematodes based on helminthological examinations of 176 specimens of freshwater fishes, belonging to 22 species, from central China (mostly lakes in Hubei Province) collected during the autumn of 2001. The following six species were recorded: Procamallanus (Spirocamallanus) fulvidraconis Li, 1935, Camallanus cotti Fujita, 1927, Dentiphilometra monopteri Moravec et Wang, 2002, Pingus sinensis Hsu, 1933, Proleptinae gen. sp. larv., and Eustrongylides sp. larv. Data on their morphology, morphological variability, host range, prevalence, intensity and distribution are provided. SEM studies of P. fulvidraconis and larval Physalopterinae, used for the first time in these species, revealed some additional morphological details and made it possible to redescribe the former. In contrast to the existing description of P. fulvidraconis, this species was found to possess two spicules and a V-shaped gubernaculum with unequal arms (originally mistaken for the left spicule), as well as deirids, whose location can be considered an important taxonomic feature. Larvae of the Physalopterinae have not previously been reported from fishes in China. The finding of larval Eustrongylides in Paramisgurnus dabryanus represents a new host record. All but one nematode species from this zoogeographically interesting region are briefly described and illustrated.
42 citations
TL;DR: The parasite causes a radial expansion of the centra and extensive dorsal and ventral outgrowths of the vertebrae leading to compression of the spinal cord and blood vessels running through the neural and haemal spines respectively.
Abstract: Myxobolus buckei sp n is described from the spinal column of Leuciscus cephalus (L), Rutilus rutilus (L) and Abramis brama (L) from freshwater rivers in the North of England The plasmodia develop within the remnants of the embryonic notochord in the intervertebral spaces The spores are large, measuring (in microm) 140 +/- 07 x 115 +/- 06 (mean +/- SD), smooth, round to ellipsoid in valvular view with several sutural edge markings The polar capsules are pyriform and of equal size, measuring 75 +/- 05 x 42 +/- 02 (mean +/- SD), with 11-12 turns of the polar filament arranged perpendicularly to the longitudinal axis of the polar capsule The parasite has a large intercapsular appendix and large iodinophorous vacuole The parasite can be differentiated from all known species of Myxobolus Butschli, 1882 by a combination of the morphological characters defined Infected fish show marked longitudinal compression of the body compared to uninfected individuals of the same year class, a feature which is pathognomonic for the disease Histologically, host responses ranged from mild hypertrophy of the zygapophyseal process and expansion of the intervertebral membrane to complete hypertrophy and fusion of the vertebrae Prominent notochord is present in the intervertebral spaces of infected fish and sporogony of the parasite leads to a vigorous focal inflammatory response involving proliferating fibroblast and osteogenic cells The parasite causes a radial expansion of the centra and extensive dorsal and ventral outgrowths of the vertebrae leading to compression of the spinal cord and blood vessels running through the neural and haemal spines respectively The parasite is considered highly pathogenic to juvenile cyprinids
39 citations
TL;DR: Henneguya pilosa sp.
Abstract: Henneguya pilosa sp. n., a new species of myxosporean from the gill filaments of the white piranha, Serrasalmus altuvei Ramirez, 1965 (Characidae), a freshwater teleost fish collected in the Zoological Garden of the city of Teresina (Piaui), Brazil, is described from light and transmission electron microscope observations. This myxosporean produced small plasmodia (up to 0.2 mm in diameter), each one containing all life-cycle stages of the parasite, including numerous spores. The spores, laterally compressed, averaged 54.2 (52.3-56.0) µm in total length and consisted of two unequal valves adhering together along the suture line and two caudal processes. The spore body measured 21.1 (20.0-23.1) µm in length, 5.9 (5.5-6.3) µm in width, and 2.2 (1.9-2.6) µm in thickness. The two equal ellipsoidal polar capsules of 7.4 (7.1-7.6) µm long and 1.2 (1.0-1.3) µm wide possessed a polar filament with 11-12 (rarely 13) turns. All surfaces of the spores were covered with a tightly adherent complex network of numerous densely ramified granulo-fibrillar masses, the longest measuring 1.5 µm long, observed around the caudal processes. The prevalence of infection was 30%. The taxonomic affinities of this parasite with other of the same genus in freshwater South American fish species are discussed.
38 citations
TL;DR: Four new species of the Monogenea were found, all belonging to Cichlidogyrus (Ancyrocephalidae), and a possible relationship between the relative size of haptoral sclerites and microhabitat selection in the studied host-parasite model is discussed.
Abstract: Tilapia cabrae Boulenger, 1899, a cichlid fish from coastal lowlands of the Republic of Congo (Africa), was examined for gill parasites Four new species of the Monogenea were found, all belonging to Cichlidogyrus (Ancyrocephalidae): C berradae sp n, C revesati sp n, C legendrei sp n, and C lemoallei sp n A possible relationship between the relative size of haptoral sclerites (ie, uncinuli compared to gripi) and microhabitat selection in the studied host-parasite model is discussed
TL;DR: The failure of infected amphipods to reduce activity levels in the presence of fish odour may reflect a parasite strategy to increase its chances of transmission by making its amphipod host more vulnerable to predation by fish.
Abstract: The acanthocephalan parasite Pomphorhynchus laevis (Muller, 1776) uses freshwater amphipods as its intermediate host. In order to complete the life cycle, the infected amphipod must be consumed by a fish, where the acanthocephalan will mature and reproduce. Parasite transmission, and therefore fitness, could be enhanced if infected amphipods fail to detect or avoid predatory fish. We compared the activity levels of infected and non-infected amphipods, Echinogammarus stammeri (Karaman, 1931), in both the presence and absence of odours from its natural, definitive host, the fish Leuciscus cephalus (L.). Throughout the experiment, infected amphipods were more active than were non-infected individuals. The non-infected amphipods reduced their activity after the addition of fish odours, but the infected amphipods failed to show a significant decrease. The failure of infected amphipods to reduce activity levels in the presence of fish odour may reflect a parasite strategy to increase its chances of transmission by making its amphipod host more vulnerable to predation by fish.
TL;DR: The analysis of interspecific relationships between infracommunities shows that negative associations are more numerous than positive associations, especially for core and secondary species.
Abstract: This work describes the ecological characteristics of the intestinal helminth communities of 50 wolves (Canis lupus L.) from Spain. The species found were classified into three groups according to prevalence, intensity and intestinal distribution. Taenia hydatigena Pallas, 1766 and Uncinaria stenocephala (Railliet, 1884) are the core species of the community. Taenia multiceps (Leske, 1780) is a secondary species. The rest of the species, Alaria alata (Goeze, 1782), Taenia serialis (Gervais, 1847), Taenia pisiformis (Bloch, 1780), Dipylidium caninum (Linnaeus, 1758), Mesocestoides sp. aff. litteratus, Toxocara canis (Werner, 1782), Toxascaris leonina (von Linstow, 1902), Ancylostoma caninum (Ercolani, 1859) and Trichuris vulpis (Froelich, 1789), behave as satellite species. The linear intestinal distribution of all helminth species was analysed. The location of most species can be considered predictable, especially for core and secondary species. The analysis of interspecific relationships between infracommunities shows that negative associations are more numerous than positive associations. The role of A. caninum in the community is compared with that of U. stenocephala.
TL;DR: This study describes a new species of Henneguya parasitizing S. spilopleura, a voracious carnivorous fish popularly known as piranhas and widely distributed throughout South American rivers, which was collected from a lake on a farm in the municipality of Campinas, state of Sao Paulo, Brazil and examined for the presence of myxosporeans.
Abstract: The class Myxosporea of the phylum Myxozoa contains 52 genera (Kent M.L., Andree K.B., Bartholomew J.L., ElMatbouli M., Desser S.S., Devlin R.H., Feist S.W., Hedrick R.P., Hoffmann R.W., Khattra J., Hallett S.L., Lester R.J.G., Longshaw M., Palenzeula O., Siddall M.E., Xiao C.X. 2001: J. Eukaryot. Microbiol. 48: 395–413), most of which parasitize fishes. Henneguya Thelohan, 1892 is the second most common of these genera and contains more than 150 species, some of which are important pathological agents (Dykova I., Lom J. 1978: J. Fish Biol. 12: 197–202; Kalavati C., Narasimhamurti C.C. 1985: Arch. Protistenkd. 129: 199–202; Lom J., Dykova I. 1995: In P.T.K. Woo (Ed.), Fish Diseases and Disorders. Protozoan and Metazoan Infections. Vol. 1. CAB International, Wallingford pp. 97–147; Martins M.L., Souza V.N., Moraes J.R.E., Moraes F.R. 1999: Rev. Bras. Biol. 59: 527– 534). In South America, Henneguya is the most abundant genus, with 31 species. To date, two species of Henneguya have been reported in Serrasalmus spp.: Henneguya iheringi Pinto, 1928 parasitizing Serrasalmus spilopleura caught in the state of Sao Paulo, and H. striolata Casal, Matos et Azevedo, 1997 parasitizing S. striolatus collected in the Amazon River estuary near Belem, state of Para, Brazil. Fish of the genus Serrasalmus are voracious carnivorous fish popularly known as piranhas and are widely distributed throughout South American rivers. In this study, we describe a new species of Henneguya parasitizing S. spilopleura. Eighteen adult and juvenile specimens of S. spilopleura were collected locally from a lake on a farm in the municipality of Campinas, state of Sao Paulo, Brazil, and examined for the presence of myxosporeans. The fish were captured between January and June 2001, and transported alive to the laboratory where they were killed by transection of the spinal cord then measured and necropsied. The measurements of 30 fresh mature spores (Lom J., Arthur J.R. 1989: J. Fish Dis. 12: 151–156) were obtained using a micrometer incorporated into a microscope eyepiece. The dimensions were expressed as the mean ± standard deviation (SD). India ink staining was used to detect the mucus envelope. The spores were checked for the presence of an iodinophilous vacuole after adding a drop of Lugol solution. Smears containing free spores were stained with Giemsa’s solution and mounted in low viscosity medium as permanent mounts (Adriano E.A., Arana S., Ceccarelli P.S., Cordeiro N.S. 2002: Folia Parasitol. 49: 259–262). For histological analysis, portions of the gills containing plasmodia were fixed in 10% buffered formalin for 24 h, embedded in paraffin, cut into sections 4 μm thick and stained with sirius red (Adriano et al. 2002, op. cit.), haematoxylin and eosin and PAS.
TL;DR: Previously undescribed third-stage larvae of two species of Spirurida were found in the haemocoel of the stalk-eyed mud crab Macrophthalmus hirtipes (Heller) (Ocypodidae) in New Zealand.
Abstract: Previously undescribed third-stage larvae of two species of Spirurida were found in the haemocoel of the stalk-eyed mud crab Macrophthalmus hirtipes (Heller) (Ocypodidae) in New Zealand. Examinations by light and scanning electron microscopy showed that the larger larvae (about 7 mm long) belonged to a species of Ascarophis van Beneden, 1871 (Cystidicolidae), the genus including parasites of fishes, whereas the smaller larvae (about 4-5 mm long) belonged to the Acuariidae, a family with species parasitic as adults mostly in aquatic birds. In a sample of 82 specimens of M. hirtipes collected in July 2002 from Papanui Inlet, on Otago Peninsula, South Island, 74 crabs (90.2%) were infected with larval nematodes with an intensity of 1-18 (mean 4.6) nematodes per crab; no distinction between nematode species was made in these estimates, although juvenile Acuariidae greatly outnumbered larval Ascarophis. Apparently, crabs play a role as intermediate hosts of these nematode species. This is the first record of larval representatives of Cystidicolidae and Acuariidae from invertebrates in the Australasian Region.
TL;DR: During a recent investigation of parasites infecting fishes from the Okavango River and Delta, Botswana (southern Africa) fourteen sharptooth catfish, Clarias gariepinus (Burchell, 1822) (Siluriformes: Clariidae) were examined for the presence of myxozoan infections.
Abstract: During a recent investigation of parasites infecting fishes from the Okavango River and Delta, Botswana (southern Africa) fourteen sharptooth catfish, Clarias gariepinus (Burchell, 1822) (Siluriformes: Clariidae) were examined for the presence of myxozoan infections. Results revealed the presence of two species of the genus Henneguya Thelohan, 1895 and one species of the genus Myxobolus Butschli, 1882 infecting this fish host. Two of the sampled fish exhibited large plasmodia of Henneguya suprabranchiae Landsberg, 1987 in the cartilage of the accessory breathing organ, another two individuals were infected with H. samochimensis sp. n. plasmodia in the gills and another three individuals revealed an infection with Myxobolus gariepinus sp. n. plasmodia in the ovaries.
TL;DR: Mormyrogyrodactylus gemini gen. et sp.
Abstract: Mormyrogyrodactylus gemini gen. et sp. n. (Gyrodactylidea: Gyrodactylidae), a viviparous monogenean is described from the skin and fins of Marcusenius macrolepidotus (Peters) from South Africa. This new genus is unique in having a large cup-shaped cirrus armed with one large needle-like spine and numerous small hair-like spinelets. A peduncular bar is present. The haptor is clearly demarcated from the body and situated on a small pedicle. The haptor has one pair of large anchors, a ventral bar complex, a small dorsal bar and 16 evenly spaced marginal hooks. The ventral bar complex consists of three parts: an inverted U-shaped piece with two semi-attached bars, each bar consisting of a base and an extension. An accessory inverted T- shaped sclerite is present on the posterior rim of the haptor. Mormyrogyrodactylus is the fifth genus of the Gyrodactylidae to be described from Africa.
TL;DR: A new myxosporean species Ellipsomyxa gobii gen. et sp.
Abstract: A new myxosporean species Ellipsomyxa gobii gen. et sp. n. is described from the common goby Pomatoschistus microps (Kroyer) (Perciformes, Gobiidae). Plasmodia with long branched pseudopodia in the gallbladder develop to subspherical bisporous plasmodia. The myxospores were found in the gallbladder, and the hepatic and bile ducts. The new genus is characterised by the morphology of the myxospores. The myxospores have smooth thin valves elongated in the direction perpendicular to the plane of the straight central transverse indistinct sutural line. The two spherical polar capsules open some distance from the sutural line on opposite sides. The new genus thereby differs from Leptotheca Thelohan, 1895. Ellipsomyxa gobii is tentatively placed in the Ceratomyxidae.
TL;DR: The presence of an anti-IL-8 activity in tick saliva indicates that neutrophils play an important role in the host response to parasitism by ticks.
Abstract: Interleukin-8 plays a critical role in inflammatory processes. Hence generation of molecules with anti-IL-8 activity is likely to be important for successful feeding and for survival of the ticks. Anti-IL-8 activity was studied in saliva of three ixodid tick species - Dermacentor reticulatus (Fabricius, 1794), Rhipicephalus appendiculatus Neumann, 1901, and Amblyomma variegatum (Fabricius, 1794). The greatest activity was shown in saliva prepared from D. reticulatus. The activity was attributed to tick salivary gland molecules that bind to IL-8, preventing binding of the chemokine to its specific receptor, rather than to occupation of the IL-8 cell receptor by the tick molecules. The distribution of anti-IL-8 activity in fast protein liquid chromatography (FPLC) fractions of salivary gland extracts (SGE) derived from adult female D. reticulatus, R. appendiculatus and A. variegatum was compared directly by both ELISA and receptor-binding inhibition assays. The correspondence in results with fractions of SGE from ELISA is consistent with detection of tick molecules that inhibit IL-8 binding to its receptor. As IL-8 is an important chemoattractant and activator of neutrophils, the presence of an anti-IL-8 activity in tick saliva indicates that neutrophils play an important role in the host response to parasitism by ticks.
TL;DR: The effect of SGE and midgut extract from both I. ricinus and D. reticulatus was examined to address the question of vector competence of these two tick species for B. burgdorferi s.l.
Abstract: The interaction between pathogen and tick vector seems to be crucial for vector-borne pathogens For instance, Borrelia burgdorferi sl, the Lyme disease agent, must overcome at least two main barriers in the tick vector body to be effectively transmitted: the midgut and the salivary glands It has been found that salivary gland extract (SGE) of ixodid ticks affects the immune system of vertebrate hosts (Ribeiro JMC 1989: Exp Appl Acarol 7: 15–20; Kuthejlova M, Kopecký J, Stěpanova G, Macela A 2001: Infect Immun 69: 575–578) and also contributes to the transmission of B afzelii to the host (Pechova J, Stěpanova G, Kovař L, Kopecký J 2002: Folia Parasitol 49: 153–159) In earlier studies it was observed that borreliae did not occur in host-seeking Dermacentor reticulatus (Fabricius, 1794) in contrast to Ixodes ricinus (L, 1758) (Hubalek Z, Halouzka J, Juřicova Z 1998: Folia Parasitol 45: 67–72), and that B garinii survived in I ricinus after experimental inoculation while it rapidly disappeared from D reticulatus (Matlova L, Halouzka J, Juřicova Z, Hubalek Z 1996: Folia Parasitol 43: 159–160) The aim of this study was to examine the effect of SGE and midgut extract (MGE) from both I ricinus and D reticulatus on the growth, motility and morphology of the B garinii spirochaete in vitro This might address the question of vector competence of these two tick species for B burgdorferi sl at the level of their compartments (salivary glands and midgut) Salivary glands and midgut were removed from 40 unfed female I ricinus and 20 unfed female D reticulatus This study attempted to simulate the effect of SGE and MGE on borrelial growth under conditions of host-seeking ticks, and therefore unfed individuals only were used Dissected organs were homogenized with a small glass blender in phosphatebuffered saline pH 70 (PBS; Oxoid), placed in microtubes, and centrifuged at 9,000 g for 10 min Clarified extracts were sterilized by filtration through the 02 μm Nanosep MF centrifugal device (Pall Corporation) and stored at –20°C Final protein content (μg/ml) of the extracts was estimated (Bradford J 1976: Anal Biochem 72: 248–254) as 328 (SGE) and 309 (MGE) in I ricinus, and 293 (SGE) and 392 (MGE) in D reticulatus In the experiments, 100 μl of each extract (or PBS in the control) were mixed with 100 μl of a 3day culture of B garinii strain BR 14 (about 10 spirochaetes per ml) in BSK-H medium with 6% of rabbit serum (Sigma) in 96-well U-bottomed sterile microplates (Sarstedt), and covered with a sterile sealing film (Denville Scientific) The microplates were placed in a 33°C incubator for 11–12 days Concentration of motile spirochaetes (the number of motile cells/ml of medium) was determined at intervals (0, 2, 4, 7, 9 and 11 days in I ricinus, and 0, 2, 5, 7, 9 and 12 days in D reticulatus), using darkfield microscopy (1) Estimation of per cent motility was determined in 3 wells per variant, when 100 randomly selected spirochaetes were screened for motility per well (2) Concentration of all spirochaetes (motile plus nonmotile) was estimated in 10-μl volumes of appropriately diluted cultures on a microscope slide with a 20 × 20 mm coverslip (Hubalek Z, Halouzka J, Heroldova M 1998: J Med Microbiol 47: 929–932); for each variant, 3 wells with 5 counts (total, 15 repetitions) were used The data were analysed with the two sample t-test using SOLO (BMDP Statistical Software) Significant differences in the concentration of motile spirochaetes were considered at P < 001 The results are summarised in Tables 1 to 3 The proportion of motile spirochaetes decreased more slowly with the extracts of Ixodes ricinus than in corresponding control (C) since day 9 post inoculation (pi) On the other hand, the percentage of spirochaetal motility decreased more rapidly with SGE and MGE from D reticulatus than in C since day 9 pi With I ricinus, the concentration of motile spirochaetes increased significantly from days 2 to 11 (pi) with both SGE and MGE compared to C In addition, the growth of spirochaetes was enhanced to a greater degree with SGE than with MGE on days 4, 7 and 9 pi With D reticulatus, a significant increase in concentration of motile spirochaetes was only detected with SGE (compared to C) on day 5 pi, while a marked decrease in concentration of motile spirochaetes was observed on day 9 pi with MGE, and on day 12 pi with both extracts compared to C Moreover, many spirochaetes grown in the presence of D reticulatus MGE were morphologically changed (compared to C and SGE) by 9 days pi; the cells were damaged (eg, less discernible walls), shorter, and with a lower number of coils The effect of SGE and MGE on the growth of B garinii spirochaetes in vitro thus differed between the two tick species tested While extracts derived from I ricinus (a competent vector for Lyme borreliosis) stimulated growth significantly, extracts from D reticulatus (a non-competent species) did not affect the growth of borreliae markedly, or even inhibited their growth on days 9 (MGE) and 12 pi (MGE and SGE) Our results therefore indicate that the tick compartment extracts surprisingly need not be inhibitory for pathogen survival in the body of even non-competent tick species like D reticulatus in a short-term exposure In such species, the role of a barrier in FOLIA PARASITOLOGICA 50: 159–160, 2003
TL;DR: Four species, Perates monops, Parasecia manueli, Beamerella acutascuta Brennan, 1958, and Blankaartia sinnamaryi, are recorded for the first time in Cuba and on new host species.
Abstract: Two new species of chigger mites, Hyponeoculta monocoxalae sp. n. from bats and reptiles, and Perares nudosetosus sp. n. from bats, are described. The first finding of larvae of Tectumpilosum negreai Feider, 1983 in nature is reported from a bat collected at the type locality, and the description of this species is emended. Four species, Perates monops (Brennan et Jones, 1960), Parasecia manueli (Brennan et Jones, 1960), Beamerella acutascuta Brennan, 1958, and Blankaartia sinnamaryi (Floch et Fauran, 1956), are recorded for the first time in Cuba and on new host species.
TL;DR: A new myxosporean species parasitizing the gall bladder of Galaxias maculatus (Jenyns), in Patagonia, was described and its coelozoic plasmodia were floating free in the bile.
Abstract: Myxidium biliare sp. n., a new myxosporean species parasitizing the gall bladder of Galaxias maculatus (Jenyns), in Patagonia, is described. Its coelozoic plasmodia were floating free in the bile. Spores are fusiform 13.7 ± 0.9 µm long and 6.9 ± 0.6 µm wide, with rounded ends in frontal view and slightly pointed ends in sutural view; shell with ridges and sinuous sutural line. Both maximum prevalence and maximum percentage of immature plasmodia occurred in summer. In winter the prevalence and the percentage of immature plasmodia fell to their lowest values. Prevalence was independent of host sex but increased with host length. Prevalence in 15 Patagonian Andean lakes (situated from 39°25'S to 41°30'S) ranged between 4.2% and 70%. Four species of Myxobolus Butschli, 1882 have been recorded from Galaxias maculatus (Jenyns) throughout its distribution range. In New Zealand, Hine (1976) described Myxobolus iucundus Hine, 1976 parasitizing muscles. In Tierra del Fuego, Szidat (1953) described M. magellanicus Szidat, 1953 in gills and M. galaxii Szidat, 1953 in muscles and organs of the abdominal cavity. In Falkland Islands Kalavati et al. (2000) described M. bartoni Kalavati, Brickle et MacKenzie, 2000 in the trunk musculature. Viozzi (1996) recorded the presence of spores of an unnamed species of Myxidium Butschli, 1882 in the gall bladder of G. maculatus in a Patagonian Andean lake. The aim of this study is to describe this new species of Myxidium, to provide information about its distribution range in north-western Patagonia and to describe the variation in its prevalence in relation to season and host sex and length from a Patagonian oligotrophic lake.
TL;DR: The results of necropsy of 1807 voles belonging to 3 species, Arvicola terrestris, Microtus arvalis (Pallas), Clethrionomys glareolus (Schreber) and 22 Apodemus sylvaticus (Linnaeus) trapped in a mountainous region of Central France between 1980 and 1990 and in 1995 are reported.
Abstract: In western Europe, the natural life cycle of Echinococcus multilocularis (Leuckart, 1863) involves mostly foxes, dogs and cats as definitive hosts and voles (Arvicolidae) as intermediate hosts. Studies on this topic are often restricted to data on prevalence of this tapeworm. However, until now, an association of E. multilocularis with larvae of another cestode species has only been reported from Rattus norvegicus in Japan (Okamoto M., Fujita O., Arikawa J., Kurosawa T., Oku Y., Kamiya M. 1992: Int. J. Parasitol. 22: 681–684). This paper reports our results of necropsy of 1807 voles belonging to 3 species, Arvicola terrestris (Linnaeus), Microtus arvalis (Pallas), Clethrionomys glareolus (Schreber) and 22 Apodemus sylvaticus (Linnaeus) (Table 1) trapped in a mountainous region of Central France between 1980 and 1990 and in 1995. They were captured alive, killed under anaesthesia and dissected. The livers were examined macroscopically for the presence of metacestodes of E. multilocularis and other cestode larval stages. Livers without macroscopical metacestodes were sectioned by hand (the thickness of sections: 1.5 mm) and observed under the dissecting microscope. All liver metacestodes were fixed in a 5% neutral formaldehyde solution. Echinococcus multilocularis metacestodes were studied by traditional histological methods. Other metacestodes were cleared or examined histologically for the presence of the hooks. The species determination of the Taeniidae was performed according to Abuladze (Abuladze K.I. 1964: Taeniata of Animals and Man and Diseases Caused by Them. Essentials of Cestodology IV. Nauka, Moscow, 530 pp.), Verster (Verster A. 1969: Onderstepoort J. Vet. Res. 36: 3–58) and Loos-Frank (Loos-Frank B. 2000: Syst. Parasitol. 45: 155–183). The species of rodents and the number of rodents infected by E. multilocularis are shown in Table 1. Larval stages of other cestodes found in voles and A. sylvaticus are summa-
TL;DR: The toxicity of cadmium and zinc at concentrations ranging from 0.1 to 100 microg/l was investigated against the activity of Diplostomum spathaceum (Rudolphi, 1819), indicating that cercariae were vulnerable during the period of maximum cercarial infectivity (0-5 h).
Abstract: The toxicity of cadmium and zinc at concentrations ranging from 0.1 to 100 µg/l was investigated against the activity of Diplostomum spathaceum (Rudolphi, 1819) cercariae. Over a 24 h exposure period a significant reduction in cercarial activity occurred in solutions of cadmium, zinc, and a mixture of cadmium and zinc at all concentrations. Reduced cercarial activity also occurred in all toxicant solutions compared with controls after only 6 h exposure indicating that cercariae were vulnerable during the period of maximum cercarial infectivity (0-5 h). The mechanisms of metal toxicity and their importance to parasite transmission are discussed.
TL;DR: New data on the geographical distribution of some nematode parasites of Salmo trutta fario L., Barbatula barbatula (L.), and Anguilla anguilla (L.) are presented.
Abstract: In the years 1999-2002, first studies were carried out on the metazoan parasites of Atlantic salmon (Salmo salar L.) recently reintroduced into the Elbe River drainage system, after more than 50 years after the complete extinction of the Elbe salmon population. A total of six helminth species were recorded from salmon smolts from three streams of the Elbe River basin (Kamenice River, Jestedský and Libocanský Brooks) in North Bohemia, Czech Republic, where S. salar fingerlings have been released since 1998: Gyrodactylus truttae Glaser, 1974, Crepidostomum metoecus Braun, 1900, Diplostomum spathaceum (Rudolphi, 1819) metacercariae, Raphidascaris acus (Bloch, 1799) adults and encapsulated larvae, Cystidicoloides ephemeridarum (Linstow, 1872), and Neoechinorhynchus rutili (Muller, 1780). Except for D. spathaceum, all these freshwater parasites have been received from the helminth fauna of the co-habiting brown trout (Salmo trutta fario L.). Due to local ecological conditions, the parasite faunae of both salmon and brown trout exhibited distinct qualitative and quantitative differences in the three localities. The finding of G. truttae on S. salar represents a new host record. Three helminth parasites of marine origin, the cestodes Eubothrium crassum (Bloch, 1779) and Scolex pleuronectis Muller, 1788 plerocercoids, and the nematode Anisakis simplex (Rudolphi, 1809) larvae were found in the single examined adult S. salar from the Kamenice River. New data on the geographical distribution of some nematode parasites of Salmo trutta fario L., Barbatula barbatula (L.) and Anguilla anguilla (L.) are presented.
TL;DR: During health surveys of 7- to 9-week-old goldfish fingerlings in a fish farm near Budapest, Hungary, myxosporean plasmodia were observed on the fins, the first European occurrence and pathological aspects of this parasite of Far-Eastern origin are given.
Abstract: During health surveys of 7- to 9-week-old goldfish (Carassius auratus L.) fingerlings in a fish farm near Budapest, Hungary, myxosporean plasmodia were observed on the fins. Plasmodia were most frequently found at the intersegmental joints of the finrays. Spores of Myxobolus diversus Nie et Li, 1973 known from China, were detectable in the mature plasmodia located within the lumen, and less often on the surface, of the cartilaginous finrays. The external wall of the plasmodia was constituted by a capsule formed from a collagenous material identical with the cartilaginous substance of the finrays. Matured plasmodia were filled by spores of 12-14 × 8-9.5 µm in size. The relatively small plasmodia caused only small deformities on the fins. Their importance is, however, not negligible, as in an ornamental fish such as the goldfish even a minor damage of the fins causes a loss of value. Besides a report on the first European occurrence and pathological aspects, a redescription of this parasite of Far-Eastern origin is given. The goldfish (Carassius auratus L.) is a popular ornamental fish species of Far-Eastern origin, which is kept in aquaria and small ornamental ponds all over the
TL;DR: Three species of Magnibursatus Naidenova, 1969 are described from marine teleosts: M. skrjabini (Vlasenko, 1931), the type species of the genus, from the gobiid Zosterisessor ophiocephalus on the Bulgarian Black Sea coast; M. bartolii sp.
Abstract: Three species of Magnibursatus Naidenova, 1969 are described from marine teleosts: M. skrjabini (Vlasenko, 1931), the type species of the genus, from the gobiid Zosterisessor ophiocephalus on the Bulgarian Black Sea coast; M. bartolii sp. n. from the sparid Boops boops off the Atlantic coast of Spain; and M. minutus sp. n. from the gobiid Neogobius eurycephalus on the Bulgarian Black Sea coast. M. bartolii differs from all other Magnibursatus species in its larger sinus-sac (length >250 µm, width >150 µm) and the more posterior location of testes. This species is also unusual in that it occurs in the branchial chamber and on the gills of its host. M. minutus is distinguished by the distinctly smaller dimensions of the body (length <1000 µm, width <200 µm), organs and eggs. These species are also distinguished from both M. caudofilamentosa (Reimer, 1971) and Tyrrhenia blennii Paggi et Orecchia, 1975. A key to the species of Magnibursatus is presented. During a survey of parasites of bogue, Boops boops (L.), off the Atlantic coasts of Spain, we came across a species possessing characteristics of two halipegine derogenid genera, Magnibursatus Naidenova, 1969 and Tyrrhenia Paggi et Orecchia, 1975. In attempting to identify the specimens we have examined comparative material (27 specimens) from Black Sea gobiid fishes provisionally identified as Magnibursatus skrjabini (Vlasenko, 1931) Naidenova, 1969 by Dr. G. Dimitrov (Bulgarian Academy of Sciences). We have found that the Atlantic form and part of the Black Sea material both show some distinctive features, which led us to describe them as new species. This paper includes a redescription of M. skrjabini and descriptions of two new species of Magnibursatus, one collected from B. boops off the Northern Atlantic coasts of Spain and the other from Black Sea gobiids. MATERIALS AND METHODS The trematodes from B. boops were dissected out from freshly frozen fish, fixed in alcohol-formol-acetic acid (AFA), transferred to 70% ethanol, stained with iron acetocarmine (Georgiev et al. 1986) and mounted in Canada balsam. Specimens from Black Sea fishes were dissected out from freshly caught fish, killed in a hot normal saline solution, transferred to 70% ethanol, stained and mounted as above. The type and voucher material is deposited at The Natural History Museum, London (BM(NH)) and in the collections of both the Central Laboratory of General Ecology, Bulgarian Academy
TL;DR: Remarkable site specificity (apical part of secondary lamellae) was observed in the course of development of microscopic lesions and Myxobolus longisporus is characterised also on the molecular level using sequences of SSU rRNA gene.
Abstract: The original description of Myxobolus longisporus Nie et Li, 1992, the species infecting gills of Cyprinus carpio haematopterus L., is supplemented with new data on the spore morphology and pathogenicity. Spores are elongate pyriform with pointed anterior end, 15.7 (15.5-16.5) mum long, 6.7 (6-8) mum wide and 5.5 mum thick. Sutural ridge is straight and narrow. Mucus envelope is lacking. Two equal-sized elongate pyriform polar capsules are 8.5 mum long and 2.5 mum wide with convergent long axes. Polar filament coiled perpendicularly to the long axis of the capsule makes 9 (8-10) turns. Posterior end of polar capsules exceeds mid-spore by 15-20%. Cyst-like plasmodia are localised in the gill secondary lamellae. The infection is described in adult big host specimens. Gross lesions manifested as dark red colouration of gill tissues were restricted to the ventral part of the first gill arches. Remarkable site specificity (apical part of secondary lamellae) was observed in the course of development of microscopic lesions. M. longisporus is characterised also on the molecular level using sequences of SSU rRNA gene. Phylogenetic analysis based on these sequences has allowed clearer phylogenetic relationships to be established with other species of the genus Myxobolus sequenced to date.
TL;DR: Type material of the proteocephalidean cestodes Manaosia bracodemoca Woodland, 1935 and Paramonticellia itaipuensis as well as recently collectedMaterial of the latter species are redescribed andParamontICEllia is considered a junior synonym of ManaosIA.
Abstract: Type material of the proteocephalidean cestodes Manaosia bracodemoca Woodland, 1935 and Paramonticellia itaipuensis Pavanelli et Rego, 1991 (both monotypic genera) as well as recently collected material of the latter species are redescribed. A close similarity between both species was observed: the shape of scoleces is identical, both possess a globular scolex with hidden suckers, a well-developed circular, horseshoe-shaped musculature surrounding suckers; the measurements of both taxa are also similar (scolex, suckers, young proglottides). Both cestodes possess a medullary ovary crossing the dorsal muscle layer and ending in the dorsal cortex, the testes are in the dorsal cortex and the cortical vitellarium is laterally situated. Both species parasitize the same fish host. Therefore Paramonticellia is considered a junior synonym of Manaosia and Paramonticellia itaipuensis becomes a junior synonym of Manaosia bracodemoca. An emended diagnosis of Manaosia, which is a monotypic genus, is provided.
TL;DR: The metabolism of the triamine spermidine is reviewed with particular focus on the biosynthesis of hypusine and homosperMidine in parasitic protozoa, i.e., Plasmodium, Trypanosoma and Leishmania, in particular in pyrrolizidine alkaloid-producing plants.
Abstract: Targeting polyamines of parasitic protozoa in chemotherapy has attracted attention because polyamines might reveal novel drug targets for antiparasite therapies (Muller et al. 2001). The biological function of the triamine spermidine in parasitic protozoa has not been studied in great detail although the results obtained mainly imply three different functions, i.e., cell proliferation, cell differentiation, and biosynthesis of macromolecules. Sequence information from the malaria genome project databases and inhibitor studies provide evidence that the current status of spermidine research has to be extended since enzymes of spermidine metabolism are present in the parasite (Kaiser et al. 2001). Isolation and characterisation of these enzymes, i.e., deoxyhypusine synthase (EC 1.1.1.249) (DHS) and homospermidine synthase (EC 2.5.1.44) (HSS) might lead to valuable new targets in drug therapy. Currently research on spermidine metabolism is based on the deposition of the deoxyhypusine synthase nucleic acid sequence in GenBank while the activity of homospermidine synthase was deduced from inhibitor studies. Spermidine biosynthesis is catalyzed by spermidine synthase (EC 2.5.1.16) which transfers an aminopropyl moiety from decarboxylated S-adenosylmethionine to putrescine. Spermidine is also an important precursor in the biosynthesis of the unusual amino acid hypusine (Wolff et al. 1995) and the uncommon triamine homospermidine in eukaryotes, in particular in pyrrolizidine alkaloid-producing plants (Ober and Hartmann 2000). Hypusine is formed by a two-step enzymatic mechanism starting with the transfer of an aminobutyl moiety from spermidine to the epsilon-amino group of one of the lysine residues in the precursor protein of eukaryotic initiation factor eIF5A by DHS (Lee and Park 2000). The second step of hypusinylation is completed by deoxyhypusine hydroxylase (EC 1.14.9929) (Abbruzzese et al. 1985). Homospermidine formation in eukaryotes parallels deoxyhypusine formation in the way that in an NAD(+)-dependent reaction an aminobutyl moiety is transferred from spermidine. In the case of homospermidine synthase, however the acceptor is putrescine. Thus the triamine homospermidine consists of two symmetric aminobutyl moieties while there is one aminobutyl and one aminopropyl moiety present in spermidine. Here, we review the metabolism of the triamine spermidine with particular focus on the biosynthesis of hypusine and homospermidine in parasitic protozoa, i.e., Plasmodium, Trypanosoma and Leishmania, compared to that in prokaryotes i.e., Escherichia coli, a phytopathogenic virus and pyrrolizidine alkaloid-producing plants (Asteraceae) and fungi.