bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunodominance, competition and evolution in immunological responses to helminth parasite antigens
Authors: Austin D. J. , Anderson R. M.
Published: June 2009

The paper describes the development and analysis of a mathematical framework for the study of the within-host population dynamics of the interaction between macroparasites and the human immune system. Simple models of this interaction based on the proliferation of T cell clones specific to parasite antigen, and the impact of clonal expansion on parasite survival, capture the basic features of age-related changes in worm loads within human communities. The model is generalized to multiple epitopes on a single antigen, and reveals competitive exclusion amongst T cells, with a single clone becoming immunodominant in the absence of cross-reactive responses and genetic variation. The introduction of genetic heterogeneity and concomitant variability in the immunogenicity of specific epitopes induces additional complexity into the dynamical interaction. Most importantly, multiple epitope models with antigenic variation suggest that the immunodominant response may not necessarily be targeted at the epitope at which some strains show the greatest immunogenicity. High immunogenicity at a particular epitope can be masked by genetic variability even though many of the variants are more immunogenic at this epitope by comparison with the epitope to which the immunodominant immunological response is directed.
Experimental Schistosoma bovis infection in goats. Circulating antigen and antibody responses to egg and adult worm antigens during infection and following treatment with praziquantel
Authors: Johansen M. V. , Fillié Y. , Monrad J. , Christensen N. Ø. , Deelder A.
Published: June 2009

Circulating antigen levels and antibody responses in Schistosoma bovis-infected West African Dwarf goats were evaluated during infection and following treatment with praziquantel (60 mg/kg) 13 weeks post-infection. One day, 1 week and 4 weeks post-treatment, subgroups of goats were sacrificed and perfused for worm recovery. For comparison, parasite-free control animals were included. Blood and faecal samples were collected biweekly. Two gut-associated schistosome antigens, circulating cathodic and circulating anodic antigen (CCA and CAA) and 3 specific antibody responses (total Ig, IgG and IgM) were measured. For specific antibody detection, crude S. bovis adult worm and egg homogenates were used. The level of CCA in the infected groups was significantly elevated from the time of onset of egg excretion onwards. However, following treatment, the CCA litres dropped to control levels within 1 week post-treatment. Strong positive correlations were found between CCA levels and worm counts and faecal egg counts during peak egg excretion. The correlations of CAA and specific antibody litres to egg and worm counts were poor. The antibody responses were all significantly elevated in the infected goats during patency, but only marginally affected by the treatment. Hence, CCA proved to be superior by correlating strongly to the level of infection and by being a sensitive indicator of the effect of treatment.
Light microscope observations of granulomatous reactions against developing Porocephalus crotali (Pentastomida: Porocephalida) in mouse and rat
Authors: Ambrose N. C. , Riley J.
Published: June 2009

The development of granulomatous reactions against moulting nymphal pentastomids (Porocephalus crotali) in the tissues of rat and mouse intermediate hosts is described. Adipose tissue and lungs are favoured sites for encystment accounting for 70% of larvae. Six moults separate the primary larva from the final infective stage which first appears about 80 days post-infection (p.i.) and is fully infective by day 120. Larvae, and particularly their cast cuticles, are the foci of granulomatous reactions characterized by an intense eosinophilia. During ecdysis, large numbers of eosinophils permeate the entire lesion but, significantly, degranulation is limited to the underside of cast cuticles where the resultant debris is endocytosed by macrophage/epithelioid cells. A pronounced asymmetry in the granulomatous lesion, evident even in the earliest cysts, results from the accumulation of individual epithelioid granulomas associated with cuticle fragments close to the ventral side of the developing parasite; each is circumscribed by fibrosis. External to this region are extensive tracts of tissue composed of mature plasma cells. Particularly in rats, large numbers of partially degranulated mast cells ( = globule leucocytes) also surround cuticle granulomas, and mast cell granules can accumulate within macrophages and fibroblasts. Inflammation slowly subsides once the infective stage is attained. This 1 cm-long larva resides in a thin, fibrotic, C-shaped cyst and can remain viable for years: uniquely this instar retains its last moulted cuticle as a protective sheath. Nymphal instars II-VI feed predominantly upon eosinophils but we do not yet know whether this requirement is obligate.
Environmental influences on egg production by the monogenean Protopolystoma xenopodis
Authors: Jackson Helen C. , Tinsley R. C.
Published: June 2009

A continuous succession of egg capsules is formed in the ootype of Protopolystoma xenopodis and released into the urinary bladder of the host, Xenopus laevis. Since egg capsules are passed out with the aquatic toad's urine several times a day, the rate of parasite egg production can be recorded accurately by direct counts. Temperature has a marked influence on the rate of egg output which doubles in response to a rise from 17 to 25 °C. Under constant temperature conditions regular egg collections from isolated toads infested with single Protopolystoma revealed that rates of production remain stable for periods of several weeks. The overall mean rate of egg production was 8·9 eggs/worm/day (e.w.d.) at 20·0±0·5 °C (based on 5 consecutive egg collections from 58 individual parasites). Significant differences were observed, however, between the mean rates of output from different hosts, ranging from 2·1 e.w.d. (s.d. = 0·6) to 17·7 e.w.d. (S.D. = 3·2). Neither differences in worm age nor host-factors could explain the observed range in output. Worms transferred to new hosts resumed egg production at pre-transfer rates, suggesting inherent differences in the capacity for egg production by individual parasites. Total production increased with increasing worm burden, but output per parasite was significantly reduced in groups of 2, 3 or 4. Whilst competition for some finite resource provides one interpretation, this observation could equally reflect a statistical phenomenon associated with the reduced chance of encountering groups of individuals which are heterogeneous for egg production as worm burden increases and sample size decreases.
Coelotrophus nudus gen. et sp.nov., an endoparasitic copepod causing sterility in a sipunculan Phascolosoma scolops (Selenka and De Man) from Sado Island, Japan
Authors: Ho Ju-Shey , Katsumi Fumimasa , Honma Yoshiharu
Published: June 2009

A new form of parasitic copepod, Coelotrophus nudus gen. et sp. nov., is described based on the specimens recovered from the coelomic cavity of a species of Sipuncula, Phascolosoma scolops (Selenka and Be Man), at Sado Island in the Sea of Japan. The new genus is distinguishable from its closest allies, Akessonia, Siphonobius and Staurosoma, in the complete absence of appendages in the female and the absence of a mouth in both female and male. The incidence of infection is fairly high (34·1%) in this population of P. scolops at Sado Island. Histological studies of the gonads and microscopical examinations of the coelomic fluid of P. scolops collected monthly from April through December, 1979 have revealed that the presence of C. nudus causes sterility in its host. Some infected P. scolops also showed a marked decrease in the number of corpuscles in the coelomic fluid.
Differentiation of major genotypes ofGiardia intestinalisby polymerase chain reaction analysis of a gene encoding a trophozoite surface antigen
Authors: Ey P. L. , Andrews R. H. , Mayrhofer G.
Published: June 2009

The polymerase chain reaction (PCR) has been used to amplifyin vitroa semi-conserved region of a gene encoding anMr68–72000 surface antigen ofGiardia intestinalistrophozoites. Using primers specific for conserved nucleotide sequences identified within the promoter-distal portion of two homologous genes (tsp11 andtsa417) cloned previously from theG. intestinalisisolates Ad-1 (from Australia) and WB (from Afghanistan), a single PCR-amplified DNA fragment of the expected size (0·52 kilobases) was obtained in high yield from either purified DNA or whole trophozoites of the Ad-1 isolate and from every 1 of 9 other axenicG. intestinalisisolates belonging to genetic groups I and II (defined previously on the basis of allozyme electrophoresis data—Andrewset al.1989). Discernible product was recovered from as few as 2–4 trophozoites. In contrast, 6G. intestinalisisolates that were assigned by allozymic analysis to genetic groups III/IV yielded small amounts of a 0·37-kilobase (kb) amplification product (with evidence in some samples of an additional 0·4 or 0·18 kb fragment) but no 0·52 kb product. Two animal-derived isolates ofG. duodenalis(one from an Australian native rodent,Notomys alexis, the other from a domestic cat) also yielded a single 0·37 kb PCR-amplified fragment, whereas an isolate from another cat produced a 0·34 kb fragment. No product was recovered fromG. muris, a morphologically distinct species ofGiardia. The results demonstrate that different genotypes ofG. duodenaliscan be distinguished using this assay and that it is diagnostic for isolates belonging to two major clusters (groups I/II and III/IV) ofG. intestinalis. The amplified DNA segment appears to be relatively conserved among group I and group II isolates ofG. intestinalis. A related but clearly distinct sequence seems to be conserved among group III/IV isolates ofG. intestinalisand some isolates ofG. duodenalis.
Stimulation of cell division and DNA replication inPrototheca richardsiby passage through larval amphibian guts
Authors: Beebee T. J. C. , Wong A. L.-C.
Published: June 2009

Prototheca richardsi, an unpigmented heterotrophic alga, causes growth inhibition in amphibian larvae and has proved refractory to culturein Vitro.P. richardsireplication is dependent on regular passaging through tadpole digestive systems; uptake of thymidine by free-livingProtothecacells and incorporation into DNA are very low by comparison with leucine uptake and incorporation into protein, but DNA synthesis is detectable in cells isolated from tadpole intestines. DNA replication was elicited 6–8 h after ingestion in protothecans fed to tadpoles and subsequently re-isolated from them, providing that the tadpoles were fed subsequent to the ingestion. It appears that passaging through tadpole intestines provides an essential stimulus to maintaining an active cell division cycle inP. richardsi.
Discrimination between six species of Theileria using oligonucleotide probes which detect small subunit ribosomal RNA sequences
Authors: Allsopp B. A. , Baylis H. A. , Allsoppi M. T. E. P. , Cavalier-Smith T. , Bishop R. P. , Carrington D. M. , Sohanpal B. , Spooner P.
Published: June 2009

The complete small subunit ribosomal RNA (srRNA) gene of Theileria parva was cloned and sequenced. Two primers were designed which permitted the specific amplification of part of the Theileria srRNA gene from Theileria-infected cell line samples which were predominantly (> 95%) bovine DNA. The sequence of the central (variable) region of the srRNA genes of T. annulata, T. taurotragi, T. mutans and two unidentified parasites referred to as Theileria sp. (buffalo) and Theileria sp. (Marula) were obtained. An alignment of the sequences was generated from which 6 oligonucleotide probes, corresponding to species-specific regions, were designed. These probes were demonstrated to provide unequivocal identification of each of the 6 species either by direct detection of parasite srRNA or by hybridization to amplified parasite srRNA genes. The probes were not able to distinguish buffalo-derived T. parva, the causal agent of Corridor disease, from cattle-derived T. parva, the causal agent of East Coast fever.
Electron microscope study of the blood stages of Plasmodium tropiduri, a lizard malaria parasite
Authors: Scorza J. V.
Published: June 2009

The study of the ultrastructure of the blood stages of P.tropiduri Aragao & Neiva, 1909 shows close similarities between this species and P.floridense, another lizard malaria parasite. The absence of a rounded structure in the merozoites of P.tropiduri, and their tendency not to project beyond the original area occupied
by the schizont are the ultrastructural characteristics that differentiate the two species.

The close relationships of homology between P.tropiduri and the Plasmodium of birds are emphasized, and new evidence on their phylogenetic relationships is offered.

P.tropiduri has a mode of ingestion and digestion similar to that of P. elongatum. When the size of the cytostome, the size of the boluses produced by the phagotrophy, and the size of the digestive vacuoles are compared, they are seen to be nearly identical in the two species.

The comparative study of the structure of the cytostomes of the merozoites and the trophozoites, and of their relationships with the membranes that limit the parasites, gives new evidence that the external membrane of the trophozoites schizonts, and gametocytes is derived from the host cell.

An exflagellatory apparatus is described from the microgametocytes of P.tropiduri, and its relationships with similar structures described from the gametocytes of avian Plasmodium and from Coccidia are discussed.
The cyclical transmission of strains ofTrypanosoma congolenseandT. vivaxresistant to normal therapeutic doses of trypanocidal drugs
Authors: Gray A. R. , Roberts C. J.
Published: June 2009

Two strains of T. congolense and two strains ofT. vivax,resistant to normal therapeutic doses of trypanocidal drugs, were transmitted byG. morsitansandG. tachinoidesthrough series of cattle in the absence of drugs to assess the transmissibility of the trypanosomes by tsetse flies and the stability of drug resistance in the organisms during cyclical development.

The characteristics of both strains ofT. vivaxand one strain ofT. congolensewere typical of the species, but the infectivity of the second strain ofT. congolensefor laboratory animals was abnormally low.

The transmissibility of the trypanosomes was assessed on the bases of the infection rates in tsetse flies used to transmit the strains and the periods required for the development of the trypanosomes in the flies and bovine hosts. The transmissibilities of both strains ofT. vivaxand the first strain ofT. congolensewere normal by comparison with data obtained by cyclically transmitting non-resistant trypanosomes of the same species, but the period required for the development of the second strain ofT. congolensein tsetse flies was abnormally long.

There was no loss of drug resistance in any of the strains examined in the experiments. A strain ofT. congolenseretained resistance to diminazene aceturate at a dose rate of 7-0 mg/kg, homidium chloride at 2-0 mg/kg, quinapyramine sulphate at 4-4 mg/kg and isometamidium chloride at 0-5 mg/kg during a series of eight transmissions by tsetse flies in a period of 376 days.
Studies on the aggregation behaviour ofNippostrongylus brasiliensis
Authors: Alphey Thomas J. W.
Published: June 2009

Two behaviour patterns which could bring about clumping inN. brasiliensis, sexual attraction and thigmokinesis, were investigated. A T-tube choice-chamber to facilitate anin vitrostudy of sexual attraction is described. A method for studying aggregation is also outlined. MaleN. brasiliensiswere shown to be attracted to female worms, positive sexual attraction. Both sexes were shown to exhibit strong thigmokinetic responses, and possible functions of such behaviour are discussed.

I am grateful to Professors J. Brough and D. Bellamy for providing the facilities during the course of this study. I should also like to thank Dr E.. A. Hammond for his supervision, help and criticism throughout the project. This work was carried out during the tenure of a Scientific Research Council Studentship.
Environmental and human influence on the ecology of Trichinella spiralis and Trichinella britovi in Western Europe
Authors: Pozio E. , La Rosa G. , Serrano F. J. , Barrat J. , Rossi L.
Published: June 2009

Surveys on Trichinella parasites in domestic and sylvatic animals collected in France, Italy, and in the Extremadura region of Spain showed that the distribution of Trichinella spiralis and Trichinella britovi is influenced by both environmental and human behaviour factors. In France, both Trichinella species are prevalent in the fox population from mountain areas and natural parks but are infrequent in wild boars (< 0·001%). In Italy, only T. britovi is present in sylvatic animals (foxes, wolves, and mustelids) living 500 m above sea level. This species is rare in wild boars ( < 0·001%) in that area. Sylvatic trichinellosis is found in only 24% and 34% of French and Italian territory, respectively, while lowland areas may generally be considered Trichinella-free, because the domestic cycle is absent. The ecology of T. spiralis and T. britovi in the Extremadura shows a different picture from that observed in France and Italy because of the presence of both domestic and sylvatic cycles. The domestic cycle not only allows the maintenance of T. spiralis in the domestic environment, but it also has a great impact on the prevalence in wild boar populations. It does not influence the prevalence in vulpine populations. These data suggest (1) that domestic trichinellosis occurs only in rural areas of Western Europe in association with traditional swine-rearing practices, but not in industrialized pig farms; (2) that sylvatic trichinellosis occurs only in natural habitats which, in Western Europe, are widespread in mountain areas; (3) that the fox is the primary reservoir in the sylvatic cycle, where the parasite is maintained in a closed circuit and (4) that among sylvatic animals T. spiralis is present at lower altitude than is T. britovi.
Purification and partial characterization of malate dehydrogenase (decarboxylating) from Tritrichomonas foetus hydrogenosomes
Authors: hrdý I. , Mertens E.
Published: June 2009

Malate dehydrogenase (decarboxylating) from Tritrichomonas foetus hydrogenosomes was purified close to homogeneity by a combination of differential centrifugation, zwitterionic detergent solubilization, Red-Sepharose chromatography and anion-exchange chromatography. The enzyme with apparent subunit size of 59 kDa and native molecular mass of 308 kDa utilized NAD+ preferentially to NADP+ as a cofactor and required Mn2+ or Mg2+ for its activity. Affinity curves for malate and coenzymes were hyperbolic. Km for malate was 100 μM and 458 μM in the presence of NAD+ and NADP+, respectively. Km for NAD+ and for NADP+ in the presence of malate was 18 μM and 207 μM, respectively. The enzyme is proposed to be a tetramer with a possible physiological role in the maintenance of an appropriate NAD+/NADH ratio in hydrogenosomes.
Random amplified polymorphic DNA technique for the identification of Trichinella species
Authors: Bandi C. , La Rosa G. , Comincini S. , Damiani G. , Pozio E.
Published: June 2009

The random amplified polymorphic DNA (RAPD) technique was successfully used to produce genetic fingerprints distinguishing between Trichinella spiralis and Trichinella britovi. The same patterns were obtained from purified and crude DNA preparations of pooled and single muscle larvae. RAPD fingerprinting was applied to muscle larvae preserved under different conditions and recovered from different hosts. Larvae recovered from fresh and frozen meat and stored at – 20 °C for a long time or under 70% ethyl alcohol at room temperature for 30 d gave good and reproducible results. Single larvae recovered from a naturally infected wild boar and from a human biopsy gave fingerprints congruent to those obtained from T. britovi reference strains. The results prove that RAPD analysis is a quick method to distinguish between the autochthonous Trichinella species of Central-Southern Europe in less than 1 d after the detection of the infection. If necessary, the biological material can be frozen or stored under 70% ethyl alcohol at room temperature and sent to laboratories able to perform the RAPD analysis. The RAPD technique requires no prior knowledge of the molecular biology of the organism to be investigated and therefore appears to be a promising tool in parasitology for the identification of sibling species.
Paramphistomum sukumum sp.nov. and other stomach-flukes from cattle in the Sukumaland area of the Lake Region, Tanganyika
Authors: Dinnik J. A.
Published: June 2009

The morphology of Paramphistomum sukumum sp.nov. from Bos indicus in the Lake Region of Tanganyika, East Africa, is described and illustrated.

A list is given showing the incidence of nine species of the family Paramphistomatidae and three species of the family Gastrothylacidae found in cattle in the Sukumaland area of the Lake Region of Tanganyika.
Some Nematoda (Strongylina and Oxyurina) from kangaroos (Macropus spp.) from Eastern Australia
Authors: Mawson Patricia M.
Published: June 2009

The collection of large numbers of nematodes from Macropus rufus from Toganmain and Wilcannia in New South Wales and Cunnamulla in Queensland and from M. canguru from Cunnamulla has made possible the revision of five species and the description of three new species. The work is divided into two sections:

(1) Strongylina. Filarinema flagrifer Mönnig, Zoniolaimus setifer Cobb, Z. cobbi Kung, Rugopharynx australis (Mönnig) and Papillostrongylus labiatus Johnston & Mawson are re-described: Pharyngostrongylus alpha Johnston & Mawson and P. beta Johnston & Mawson are recognized as synonyms of R. australis; Filarinema moennigi sp.nov. is described from Macropus rufus.

(2) Oxyurina. Macropoxyuris longigularis gen.nov., sp.nov., and M. brevigularis gen.nov., sp.nov., are described from M. canguru. Re-examination of paratype material of oxyurids previously recorded from marsupials has made possible the presentation of more detailed descriptions, and the following nomenclatural changes become necessary: Oxyuris (s.l.) acuticaudata Johnston & Mawson is a synonym of Austroxyuris finlaysoni Johnston & Mawson: Syphacia trichosuri Johnston & Mawson is considered as Oxyuris (s.l.) trichosuri; two new genera are proposed, Potoroxyuris, for Oxyuris (s.l.) potoroo Johnston & Mawson, and Paraustroxyuris for Passalurus parvus Johnston & Mawson. Figures are given of Passalurus ambiguus (Duj.).

The material studied was made available by the generosity of Dr R. Mykytowycz of the C.S.I.R.O. Division of Wildlife Research, Canberra, to whom I am most grateful.

I am also indebted to Dr R. J. Ortlepp, Division of Veterinary Services, Onderstepoort, South Africa, for the gift of a sample of Rugopharynx australis, to Dr M. J. Mackerras, then of the Queensland Institute of Medical Research, for material from Macropus canguru from centres in south eastern Queensland, and to Dr G. B. Sharman of the C.S.I.R.O. Division of Wildlife Research for information on the correct names of the host species.
Nematode parasite populations in cattle in Fiji: a humid tropical environment
Authors: Donald A. D.
Published: June 2009

Observations are reported on the fluctuations in populations of gastro-intestinal nematode parasites in 68 calves on two dairy farms in Fiji based on fortnightly faecal worm egg counts over a 3-year period. On one of the farms the calves began to graze soon after birth; on the other farm they were reared indoors until they were weaned at 6 months of age.

The important species were Cooperia spp., Bunostomum phlebotomum, Haemonchus placei, H. similis and Oesophagostomum radiatum. Only small numbers of Trichostrongylus spp., Mecistocirrus digitatus and Neoascaris vitulorum were present.

Potentially pathogenic worm burdens were only found in young cattle, mostly between 2 and 15 months of age. Faecal egg counts for each parasite species rose independently to a peak and then declined to low levels. For most species there was a close relationship between the time at which the peak faecal egg count occurred and the age of calves on the same farm, irrespective of the season in which the calves began to graze. This is considered to be due to the high rainfall and constant high temperatures throughout the year resulting in at least minimal favourable conditions for the development and survival of the pre-parasitic stages of all species in all months of the year. It is concluded that the succession of species which occurred must be strongly influenced by intrinsic factors in the life-history of each parasite.

Tere were differences in the levels of peak egg counts between groups of calves which began to graze in different seasons but almost all parasite species examined were affected equally. The lowest levels were recorded in calves which were first exposed continuously to infection at the beginning of the dry season and the highest levels in those exposed at the beginning of the wet season.

Protection of calves from parasite infection, by indoor rearing until weaning at 6 months of age, did not confer any striking advantage as the acquisition of potentially pathogenic worm burdens was merely delayed.

The results are discussed in the light of recent theoretical concepts regarding the immunological control of helminth parasite infection.

I am indebted to Mr A. E. Harness of Wainivesi for permitting observations to be made on his dairy farm, to Deo Raj Singh and Ram Kumar for technical assistance, and to Dr D. F. Stewart and Dr J. K. Dineen of the McMaster Laboratory for their criticism of the manuscript. My thanks are due to Miss Suzanne Dodd and Mr I. T. Roper of the McMaster Laboratory for the preparation of the figures. The permission of the Director of Agriculture, Fiji, to publish this paper is gratefully acknowledged.
A comparative study of the movement of some microphagous, plant-parasitic and animal-parasitic nematodes
Authors: Wallace H. R. , Doncaster C. C.
Published: June 2009

Ciné film and direct observation showed that microphagous, plant and animal nematodes have the same basic wave pattern when moving. Their speed is linearly related to the product of their length and wave frequency during unrestricted movement in deep water. The speed, wave pattern and frequency of the plant nematode Ditylenchus dipsaci and the animal nematode Trichostrongylus colubriformis changed in a similar way in response to changes in water film thickness on the surface of agar of different concentrations. T. colubriformis like D. dipsaci were most mobile in a sand-water medium at a suction corresponding to the stage when most of the water has drained from the pores. The optimum temperature for activity of T. colubriformis and D. dipsaci was about 20° C. and both survived desiccation at 50% relative humidity and 24° C. for 32 days. T. colubriformis was attracted to and aggregated around grass roots (Phleum pratense). The results suggest that the free-living stages of microphagous, plant parasitic and animal parasitic nematodes move similarly and that nematodes can be divided arbitrarily into three groups: (1) those active enough to swim in deep water; (2) those able to swim in thick water films, escape from the soil and ascend plants above ground level; and (3) those too inactive to swim, the crawlers, which are largely confined to the soil. The habitat of free-living stages of nematodes, irrespective of their host or feeding habits, is probably related to their propulsive power.

We thank Dr D. Poynter for supplying the animal parasites used.
An outbreak of helminthiasis in pheasant chicks due to Plagiorchis (M.) megalorchis Rees 1952; with some critical remarks on P. (M.) laricola Skrjabin 1924
Authors: Rayski C.
Published: June 2009

Large numbers of Plagiorchis (M.) megalorchis Rees, 1952, were found in the small intestine of dying pheasant chicks in Peeblesshire, Scotland. This is the first record of this trematode in pheasants. In one chick one specimen of Brachylaemus fuscatus (Rud, 1819) was found, which is a new host record in this country. Unusual virulence of these trematodes in pheasants and turkeys is noted, showing lack of adaptation to these hosts. In addition to chironomids and midge, culicine larvae were infected with cercariae from naturally infected Lymnaea pereger. It is proposed to consider P. laricola Skrjabin as described and illustrated by Chertkova (1953) to be Plagiorchis bikhovskayae n.nom.

The author wishes to express his thanks to R. H. Duff, M.R.C.V.S., of the Ministry of Agriculture, Veterinary Laboratory, Lasswade, for placing the first pheasant chicks at his disposal, and to A. Howe, the gamekeeper at Holylee, for his information and willing help.
Enzymatic amplification of mini-exon-derived RNA gene spacers of Leishmania donovani: primers and probes for DNA diagnosis
Authors: Hassan Q. , Ghosh A. , Ghosh S. S. , Gupta M. , Basu D. , Mallik K. K. , Adhya S.
Published: June 2009

The multicopy mini-exon-derived RNA (med RNA) locus of Leishmania donovani was enzymatically amplified by the polymerase chain reaction (PCR). The major 180 bp PCR product contained conserved med RNA gene sequences flanking the variable intergenic spacer from the med RNA gene tandem repeat. The oligonucleotide primers cross-reacted with other Leishmania species. In serial dilution experiments, positivity in the PCR assay was observed down to the genomic DNA equivalent of less than a single Leishmania cell. When the major PCR products from Indian L. donovani isolates were cloned and used as probes in dot hybridization analyses, they discriminated between L. donovani and L. amazonensis, L. major and L. infantum under high stringency conditions. DNA from spleen biopsies and blood samples of confirmed kala azar patients was positive, as were two skin biopsies from patients with post-kala azar dermal leishmaniasis (PKDL). These observations demonstrate that PCR amplification of med RNA intergenic spacers is sufficiently sensitive for clinical diagnosis of kala azar and PKDL, and furthermore, that cloned intergenic spacer probes may be useful for identification and classification of L. donovani.
Cloning of the rDNA repeat unit from a British entomopathogenic nematode (Steinernematidae) and its potential for species identification
Authors: Reid A. P. , Hominick W. M.
Published: June 2009

The entire ribosomal DNA repeat unit of a steinernematid species (Nashes isolate) was cloned as three separate EcoR I fragments in the plasmid pUC18. An equimolar cocktail of these three clones was used to identify Steinernema species on Southern blots as each species displays its own unique restriction fragment length polymorphisms. The clones also identified two new species isolated in a soil survey of coastal regions of Britain. One of the clones (pSn4.0) can detect length heterogeneities in the rDNA repeat unit of various isolates of some of the species, particularly the most common in the United Kingdom, S. feltiae. These differences in the rDNA repeat unit length remained constant over several years for one isolate of S. feltiae, but were different for each of the geographical isolates studied to date.
Trypanosoma brucei: characterization of protein kinases that are capable of autophosphorylation in vitro
Authors: Hide G. , Graham T. , Buchanan N. , Tait A. , Keith K.
Published: June 2009

Autophosphorylation by protein kinases has been implicated as an important control mechanism in signal transduction and growth regulatory pathways in mammalian cells. We have set out to investigate whether any such autophosphorylating protein kinase activities can be found in Trypanosoma brucei. In order to do this, we have developed a system for characterizing such protein kinase activities using an in vitro assay. This assay was carried out by fractionation of trypanosome lysates using isoelectric focusing gel electrophoresis followed by incubation of the gel in γ32P-labelled nucleotide triphosphate and subsequent autoradiography. We have identified two classes of autophosphorylating protein kinase activities. In the first class all were dependent on ATP as the phosphate donor substrate and were all found to have a molecular size of 60 kDa. Differences in the activity of these protein kinases were observed between the bloodstream and procyclic life-cyle stages. Furthermore, the addition of mammalian epidermal growth factor to bloodstream stage lysates stimulated an additional activity. The second class of autophosphorylating protein kinases utilized GTP as the phosphate donor and were all found to be 90 kDa in size. Stage-specific differences were also observed in the activity of these protein kinases.
Cyclosporin A: drug treatment in vivo affects the kinetics of [14C]glucose transport in Hymenolepis microstoma in vitro
Authors: Wastling J. M. , Chappell L. H.
Published: June 2009

The transport of [14C]glucose by Hymenolepis microstoma in vitro following in vivo treatment with cyclosporin A (CsA) was determined over a range of concentrations. For untreated (control) worms glucose uptake showed saturation kinetics with a small diffusion component. Estimates of the maximum velocity of glucose uptake (Vmax) and the affinity of substrate for the glucose transporter (Kt) revealed that untreated 8-day-old worms had a Vmax twice that of 15-day-old worms and that younger worms had a lower Kt. An inverse relationship was demonstrated between log10 worm weight and the rate of uptake of [14C]glucose, reflecting the relatively greater number of glucose transporters due to the larger surface area: volume ratio of smaller worms. Treatment of H. microstoma with CsA in vivo significantly increased the diffusion component of glucose uptake in vitro. Parasites from drug-treated mice had a significantly lower Vmax for glucose uptake than size-matched controls. The affinity of glucose for its transporter in CsA-treated worms (Kt) was not significantly different from size-matched controls. Both juvenile and adult worms underwent transient depletion in total glycogen content after CsA treatment in vivo. The data confirm that CsA treatment in vivo disrupts the functional integrity of the worm tegument, one facet of which is impaired acquisition of glucose.
The development and morphology of Polycercus lumbrici (Cestoda: Cyclophyllidea)
Authors: Scott J. S.
Published: June 2009

Polycercus lumbrici, previously described only by Metchnikov (1868) in Russia, has been found in Scotland in the earthworm Allolobophora terrestris.

Experimental infestation of earthworms with Polycercus lumbrici as a result of feeding them with the eggs of Paricterotaenia paradoxa shows that the proliferating cysts are the larvae of the latter as suggested by Joyeux and Baer (1939).

There is evidence that Polycercus may induce parasitic castration of the earthworm in which it occurs.

Metchnikov's description of the development of the larva is confirmed for the most part but is modified to include a retroversion of the larva in its early stages of development. The development of the scolex is shown to follow a pattern similar to that of Cysticercus fasciolaris in that the hooks are borne on a ‘prebulb’ which later invests a ‘bulb’, the former giving rise to the muscles of the walls of the double sac of the rostellum, the latter to the hook-elevator muscles.

The rostellar hooks of P. paradoxa are elevated by the action of a double layer of muscles which radiate from a conical invagination of the bulb. These muscles, in association with the muscles of the wall of the rostellum, elevate the hooks by modifying the shape of the rostellum rather than by direct action on the hooks.

The nervous system and the excretory system in the scolex of P. paradoxa are briefly described and the nature of the ‘glandular’ structure of the rostellum is discussed.

I wish to record my gratitude to Professor H. G. Callan for affording me the facilities for my work and to the many persons, too numerous to mention by name, who helped me to obtain my material. I am particularly indebted to Mr D. R. R. Burt for guidance and constructive criticism at all stages of my work and to Mr I. M. Sandeman for much helpful advice.

The work was carried out during the tenure of Research Grants from Madras College, St Andrews, and from the D.S.I.R., to whom I would express my appreciation for their aid.
Studies on the excretory system of amphistome parasites of ruminants
Authors: Tandon R. S.
Published: June 2009

The excretory systems of Gastrothylax crumenifer, Fischoederius elongatus and F. cobboldi have been described. In all three species it shows the characteristic, more or less H-shaped, pattern of the amphistome excretory system.

The difference between the systems in the three species lies in the nature of the branches of the anterior portions of the longitudinal excretory ducts, in the transverse excretory ducts and the branches received by them and in the number of flame cells at the ends of the capillaries.

The main longitudinal excretory ducts run internal to the intestinal caeca in G. crumenifer and F. cobboldi, while in F. elongatus they run almost external to the caeca and maintain this position even in the posterior half of the body, where the caeca are not present.
Studies on the Functional morphology of the Scolex and of the Genitalia in Echinobothrium brachysoma Pintner and E. affine Diesing from Raja clavata L.
Authors: Rees Gwendolen
Published: June 2009

1. Echinobothrium brachysoma Pintner and E. affine Diesing have been found in the spiral valve of Raja clavata L. off the coast of Britain.

2. The spiral valve is lined by tubular crypts into which the scolices of the worms are thrust, the strobila, with one gravid proglottid, being free in the lumen.

3. The functional morphology of the scolex of E. brachysoma has been described. That of E. affine appears to be similar.

4. The scolex adheres, mainly, by the apical hooks which can be raised by inner and outer elevator muscles attached to their roots and closely associated with the rostellum.

5. The rostellum can be protruded by the contraction of a dorsal and a ventral protractor muscle. Movements of the rostellum elongate the scolex in a dorsoventral direction, forcing the apical hooks against the crypt wall and supporting them.

6. The peduncle hooks are not often embedded in the epithelium. Both series of hooks damage the epithelial lining of the crypt.

7. The remaining musculature, excretory and nervous systems are described.

8. The genitalia are essentially the same in both species. The number of testes varies from one proglottid to another in the same worm. In E. brachysoma the mid-ventral genital atrium is near the posterior end which affects the course of the vagina. The eggs in both species include two yolk cells which are similar to those of the Digenea and Pseudophyllidea.
Two new species of cryptobiotic (anabiotic) freshwater nematodes, Actinolaimus hintoni sp.nov. and Dorylaimus keilini sp.nov. (Dorylaimidae)
Authors: Lee D. L.
Published: June 2009

Dr H. E. Hinton, who is working upon the larva of a chironomid, Polypedilum vanderplanki Hinton (1951), found in dried mud from shallow rock pools at Anara, alt. 2500 ft., about 20 miles south-east of Kaduna in Northern Nigeria, noticed that there were nematodes in this dried mud which revived when placed in water and very kindly sent me the material to examine from Hinton
Comparison of penetration and maturation of Schistosoma mansoni in four strains of mice
Authors: Stirewalt M. A. , Shepperson J. R. , Lincicome D. R.
Published: June 2009

Penetration and maturation of Schistosoma mansoni were compared in four strains of mice under controlled conditions, with the C3H as the reference strain. Differences were observed in (1) average numbers of cercariae penetrating, (2) percentage of individual mice penetrated by at least 90% of the available cercariae, (3) worm burdens, (4) maturation of penetrants, and (5) consistency of mice with reference to these characteristics. Criteria 2, 4 and 5 have not been evaluated in this way before.

Best average penetration (47%), greatest consistency, and highest percentage of samples with at least 90% of the cercariae penetrating were in mice of the C3H strain (85%). Of the other strains the Swiss albino strain most resembled strain C3H. Beige and hairless mice were comparatively resistant to penetration since only 60 and 30% respectively of these hosts had at least 90% of the cercariae penetrating. Hairless mice gave the best average worm recovery (23%) and parasite maturation (53%) and beige the poorest (15 and 34%). Mice of the Swiss and beige strains were highly variable in terms of parasite maturation.

The establishment of reproducible differences in infections of hosts at the sub-specific level provides basic information for investigation of factors which influence penetration and maturation and which are thus involved in host specificity and innate resistance in closely related animals.

The authors are grateful to Dr Margaret Deringer, National Cancer Institute, National Institutes of Health, for the hairless mice and to Mildred Walters, Naval Medical Research Institute, for assistance in the production of cercariae.
On species of the genusCapillariaZeder, 1800 (Nematoda) from British domestic fowl
Authors: Wakelin D.
Published: June 2009

Four species of the genusCapillaria—C. anatis, C. bursata, C. caudinflataandC. obsignata—are described from the domestic fowl.C. bursataconstitutes a new species record for Britain. Taxonomic problems concerning these species in particular, and ofCapillariaspecies in general, are discussed in the light of experience gained from the present study.

This work was carried out during the tenure of a British Egg Marketing Board research studentship and is part of a thesis accepted by the University of London for the Ph.D. degree. My thanks are due to the director of the Houghton Poultry Research Station for granting facilities for work and to the staff for their help and encouragement. Mr R. A. Avery kindly supplied me with material collected from the Wildfowl Trust, Slimbridge.
A revision of the genusKhaliliaNeveu-Lemaire, 1924 (Nematoda: Strongyloidea)
Authors: Ogden Colin G.
Published: June 2009

It is established that the generaAmiraLane, 1914, andAmiroidesStrand, 1929, are synonyms of the genusKhaliliaNeveu-Lemaire, 1924.

The two valid species,K. sameeraandK. pileata, are redescribed.

K. sameerais designated as the type-species of the genus.

K. butaandK. rhinocerotisare considered to be synonyms ofK. sameera, whilstK. straeliniis considered to be aspecies dubia.

I wish to express my thanks to Dr W. G. Inglis, British Museum (Natural History), for his advice and criticism, and to Mr S. Prudhoe, British Museum (Natural History), for reading this paper in manuscript.

I would also like to thank Dr P. L. G. Benoit, Musée Royal de I'Afrique Centrale, Tervuren, Belgium, for the loan of material used in this study, and to Dr R. P. Lee, University College Dublin, Ireland, for the donation of specimens ofK. sameera.
Investigations on osmotic regulation in the parasitic nematode,Aspiculuris tetrapteraSchulz
Authors: Anya A. O.
Published: June 2009

In the mouse pinworm,Aspiculuris tetraptera, the basic features of the process of osmotic regulation is similar to the process in other nematodes such asParascaris equorum, Rhabditis terrestrisandHammerschmidtiella diesingi.The ability to osmoregulate is, however, utilized more effectively in a hypertonic than in a hypotonic solution.

The body fluid is isotonic with 35 % sea water. The relative accuracy of this value is confirmed by direct measurements of the depression of freezing point of the body fluid. This is approximately 0.68–0.69 °C, which is approximately 0.12 % NaCl, which is higher than the value forAscaris(= 0.655 °C).

My thanks are due to Dr D. L. Lee for helpful discussions on some aspects of this study.
The biology ofLeptocotyle minor, a skin parasite of the dogfish,Scyliorhinus canicula
Authors: Kearn G. C.
Published: June 2009

Leptocotyle minoris a monogenean parasite specialized for living on the denticlecovered skin of the dogfishScyliorhinus canicula. Each adult parasite attaches itself to the outer surface of a single denticle. Small postlarvae are found on the inner surfaces of the denticles. The denticles have hard enamel on both inner and outer exposed surfaces. Haptoral hooks, such as are present in other monogenean oncomiracidia, would be unable to penetrate this hard surface and are absent in postlarval and adult parasites which attach themselves by cement. The oncomiracidium possesses six haptoral spicules which may be homologues of the marginal hooks of other monogeneans, but these spicules disappear early in postoncomiracidial development.

Adult parasites feed on the host's epidermis which lies between the denticles. The position of small postlarvae on the inner surfaces of the denticles enables them to reach the epidermis for feeding purposes. Growth then permits young parasites to migrate away from the epidermis on to the outer surfaces of the denticles.

Adult parasites move from one denticle to another in a leech-like manner, and copulation occurs between parasites which meet as a result of these movements.

I am grateful to the Director and Staff of the Plymouth Laboratory for their hospitality and particularly to Mr J. E. Green for his interest and co-operation.
The structure and function of the adhesive organ in strigeid trematodes
Authors: Öhman Christina
Published: June 2009

A short account of the biology and life-cycle of Diplostomum spathaceum is given.

The morphology of the forebody is described in some detail. The lappets are well developed and function as organs of attachment as well as being reservoirs for the secretion from the forebody gland cells. The adhesive organ is variable in form and the muscles facilitating the movements are described in detail. Pressure changes in the excretory system are thought to assist in evaginating the adhesive organ.

The histochemical tests gave the following results. The phosphatases present in the adhesive organ and the forebody gland cells are of the acid variety, the alkaline phosphatase is only present in the cuticle, traces of it occur in the lappets and forebody gland cells. No leucine aminopeptidase activity was observed. The esterase present is either a pseudocholinesterase or a non-specific B-esterase. The presence of RNA is confined to areas of enzyme formation.

The in vitro studies confirmed the absence of alkaline phosphatase and the presence of acid phosphatase and esterase in the forebody. They also showed a secretion of acid phosphatase and esterase to the exterior of the parasite.

Diplostomum spathaceum has very little effect on the host mucosa, but some lysis of the host tissues in contact with the forebody and especially the lappets, is observed. The response of the host to the parasite is likewise very small.

The source of nutrients for D. spathaceum is believed to be the contents of the host alimentary tract, host mucus secretions and to a small extent disintegrated host tissues.

I am very grateful to Dr D. A. Erasmus for advice and encouragement during this study and to Professor J. Brough for his interest and for provision of excellent working facilities. The work was conducted during the tenure of a Rotary Foundation Scholarship for International Understanding and a grant from Nylands Nation (Helsingfors, Finland).