bluuebunny/crossref_metadata_2025_split huggingface dataset:
The attachment site, invasion route and larval development ofTrochopus pini, a monogenean from the gills ofTrigla hirundo
Authors: Kearn G. C. 
Published: June 2009

Adult specimens ofTrochopus piniattach themselves by folding the disk-shaped haptor around the edge of the host's primary gill lamella. They are able to move from one place to another with the aid of disk-shaped pads on the head region.Ducts from the posterior median gland cells, which are extensive in the head region of the adult, open on the periphery of each disk and exude an adhesive secretion.The oncomiracidium ofT. piniis described and evidence is offered in support of direct invasion of the gills by these free-swimming larvae. Special attention is paid to the development of the head region of the parasite. Newly attached larvae lose their eye lenses and possibly their anterior median gland cells; their lateral head glands are well developed and most probably serve for attachment of the head region, since the posterior median gland cells are poorly developed and appear to have no ducts. Later the posterior median gland cells and their ducts increase in numbers and, in association with the pads on the head region, take over from the lateral glands the job of attaching the head region.The paths of the tendons associated with the accessory sclerites on the haptor ofT. piniindicate that this gill parasite has evolved relatively recently from the ancestors of benedeniid skin parasites.I am most grateful to Commander J. Pareira, the Director of the Aquario Vasco da Gama in Lisbon where most of this work was done, and to the Staff of the Aquario and especially to Mr A. Ferreira. I am indebted to the Calouste Gulbenkian Foundation for a generous grant which made this visit possible. I am grateful also to the Directors and Staff of the Laboratoire Arago, Banyuls, France, the Station Biologique of the University of Bordeaux at Arcachon in France, and the Laboratory of the Marine Biological Association of the United Kingdom at Plymouth, England. I would like to thank the Royal Society for a grant from the Browne Fund which enabled me to work at Banyuls in 1962 and for a Pergamon Travel Award which made it possible to visit Arcachon in 1967.
Studies of the antibody-dependent killing of schistosomula ofSchistosoma mansoniemploying haptenic target antigens. Analysis of mechanisms responsible for the rejection of parasitesin vivo
Authors: Moser Gina , von Lichtenberg F. , Sher A. 
Published: June 2009

SUMMARYSchistosomula, surface labelled with trinitrophenyl (TNP) target antigens were tested for their susceptibility to killing by humoral- or cell-mediated anti-TNP effector mechanismsin vivo. It was found that mice passively immunized with anti-TNP serum effectively rejected an intravenous (i.v.) challenge infection with TNP-labelled schistosomula. In contrast, mice which demonstrated a strong TNP-specific, delayed hypersensitivity response to the haptenated larvae as evidenced by ear swelling, were unable to eliminate the same challenge infection. Significant passive immunization against TNP-labelled schistosomula was shown to require microlitre quantities of anti-TNP serum and could be conferred with an IgG fraction purified from the serum. The role of cells in the antibody-dependent rejection of TNP-labelled schistosomula was investigated using histopathological methods. In passively immunized mice, haptenated larvae elicited neutrophil-enriched focal reactions in the lungs and showed evidence of degeneration as early as 2 h after injection. These cellular reactions were not observed in recipients which had received prior whole-body irradiation. Nevertheless, by 24 h TNP-labelled larvae were found to have been killed in the lungs of the irradiated mice despite the absence of significant cellular attack. The above observations suggest that the antibody-dependent destruction of haptenated schistosomula results from two overlapping responses, an early response mediated by radio-sensitive cells and a second, radio-resistant response manifesting its effects at later time points. Since mice genetically deficient in the fifth component of complement fail to develop the later response, it probably reflects the effect of the lytic pathway of complement on the parasite.
Identification of the fragment containing cross-reacting antigenic determinants in the variable surface glycoprotein ofTrypanosoma brucei
Authors: Barbet A. F. , Musoke A. J. , Shapiro S. Z. , Mpimbaza G. , McGuire T. C. 
Published: June 2009

SUMMARY125I-labelled, isolated variable surface glycoproteins (VSGs) ofTrypanosoma b. bruceibind both homologous and heterologous anti-VSG sera and binding to heterologous antisera may be blocked by other unlabelled VSGs (Barbet & McGuire, 1978). This paper presents results which suggest that oligosaccharide residues have importance in the antigenic structure of VSG cross-reacting determinants. The ability of VSG to bind heterologous anti-VSG sera was destroyed by periodate oxidation but not by extensive proteolysis. A VSG glycopeptide fragment was isolated from two different VSGs, which blocked by 100 % the binding of VSG to heterologous anti-VSG sera and therefore contained the cross-reacting determinants. The native glycopeptide fragment was resistant to digestion with trypsin, pronase or leucine aminopeptidase and prolidase. We also show that a VSG synthesized in the reticulocyte lysate cell-free system was not immunoprecipitated by heterologous anti-VSG sera in contrast to the same VSG labelled by metabolic incorporation of [35S]methioninein vivo.
Identification and diagnosis ofLeishmania mexicanacomplex isolates by polymerase chain reaction
Authors: Eresh S. , McCallum S. M. , Barker D. C. 
Published: June 2009

SUMMARYFollowing cloning ofLeishmania(L.)amazonensiskinetoplast DNA two recombinant clones were identified: one specific forL. (L.)amazonensisand the other specific forL. (L.)amazonensisand closely related isolates. DNA sequences from these clones were compared with those of other kinetoplastids and oligonucleotide primers were designed to be used in the polymerase chain reaction. A pair of these primers has been shown not only to be highly specific forL. mexicanacomplex isolates but can also be used to distinguish betweenL. (L.)mexicanaandL. (L.)amazonensisisolates. These primers have been tested with water-lysed cultures, crude DNA extracts from human patients, potential host reservoirs, sandfly vectors and with cell pellets after isoenzyme characterization. The results of these tests indicate that the primers can be used specifically in the presence of excess host DNA originating from the majority of South American countries.
Observations on the effects of different chemotherapy strategies on the transmission of Schistosoma mansoni in Machakos District, Kenya, measured by long-term snail sampling and cercariometry
Authors: Sturrock R. F. , Klumpp R. K. , Ouma J. H. , Butterworth A. E. , Fulford A. J. C. , Kariuki H. C. , Thiongo F. W. , Koech D. 
Published: June 2009

SUMMARYTransmission of Schistosoma mansoni was monitored by routine snail sampling for Biomphalaria pfeifferi and by supplementary cercariometric measurements in 4 neighbouring study areas in Machakos District, Kenya. After 1 year, extensive, population-based chemotherapy with a single dose of praziquantel was given in 3 areas, but only minimal treatment in the fourth. In the year preceding treatment, seasonal transmission of S. mansoni and other non-human trematodes occurred in all 4 areas, despite some ecological differences and the effects of earlier treatment campaigns in 1 of the study areas. After treatment of all infected subjects in one area in which there had been earlier chemotherapy campaigns, S. mansoni transmission remained very low. It was reduced for at least 2 years after chemotherapy targeted at either all heavily infected subjects or all infected school children, but it was unaffected in an area where treatment was restricted to those few very heavily infected cases at risk of developing, disease. Nowhere was transmission entirely eliminated by chemotherapy and that of non-human trematodes continued unabated. The snail data correspond well with the human, parasitological data. Targeting school children was as effective as more extensive campaigns, but chemotherapy alone never stopped S. mansoni transmission: reinfection was inevitable, at rates determined by ecological factors affecting snail populations.
Altered behaviour of carbohydrate-bound molecules and lipids in areas of the tegument of adultSchistosoma mansoniworms damaged by praziquantel
Authors: Lima S. F. , Vieira L. Q. , Hardert A. , Kusel J. R. 
Published: June 2009

SUMMARYBy using fluorescent probes the distribution and fluid properties of lipid and saccharide-bound molecules was assessed in the tegument of praziquantel (−) treatedSchistosoma mansoniadult male worms. Our results show that higher amounts of glycoproteins and/or glycolipids are exposed in damaged areas of the membrane compared with undamaged ones. At damaged regions these molecules present high lateral diffusion coefficient and mobile fraction values which suggests that after praziquantel(−) treatment they are being shed by the worm into the medium. The lateral diffusion coefficient of the lipid analogue 5'-octadecanoyl aminofluorescein is unchanged in damaged or undamaged areas but the mobile fraction is significantly reduced at damaged areas. The immunological significance of these altered surface properties is discussed.
Characterization of a major surface-associated excretory–secretory antigen ofTrichinella spiralislarvae with antibodies to keyhole limpet haemocyanin
Authors: Modha J. , Robertson W. M. , Kennedy M. W. , Kusel J. R. 
Published: June 2009

SUMMARYA multi-subunit antigen (nativeMr> 200 kDa, reducedMr97–100 kDa) has been identified in homogenates ofTrichinella spiralislarvae using affinity-purified rabbit anti-keyhole limpet haemocyanin (KLH) antibodies and its cross-reactivity with KLH was confirmed by competition blotting. The antigen was not present at the larval surface but was exposed after treatment of the larvae with the detergent cetyltrimethyl ammonium bromide (CTAB) which removed the surface coat. This correlated with a significant decrease in insertion of the surface-restricted fluorescent lipid probe AF18, indicating that the surface coat must be lipidic in nature. Unlike KLH, the larval antigen blotted onto nitrocellulose was itself periodate insensitive. Periodate treatment of whole larvae, however, resulted in shedding of the surface, to which anti-KLH antibodies then bound intensely. Anti-KLH antibodies also recognized three (49, 55, 108 kDa) of the four most dominant antigens in excretory–secretory (ES) products of cultured larvae, whose excretion–secretion was increased with CTAB. The nature, location and function of the antigen is discussed.
Detection of parasites of theLeishmania donovani—complex by a polymerase chain reaction—solution hybridization enzyme-linked immunoassay (PCR—SHELA)
Authors: Qiao Z. , Miles M. A. , Wilson S. M. 
Published: June 2009

SUMMARYA polymerase chain reaction (PCR) based on the detection of the Lmet2 repeat sequence specific to members of theLeishmania donovani–complex is described. To improve PCR specificity, a post-PCR hybridization step is often performed but this usually involves an entirely new procedure with additional manipulations, expense and time. We have simplified this post-PCR hybridization by developing a strategy which includes the probe in the PCR and enables the hybridization to be performed automatically as part of the PCR programme. The hybrids are afterwards detected by capture in microtitre wells and colorimetric visualization. This method, which we have termed PCR-solution hybridization enzyme-linked immunoassay (PCR–SHELA), is rapid, able to detect less than 5 cultured parasites and is specific for parasites of theLeishmania donovani–complex. We also describe the application of PCR–SHELA to the detection of amastigotes in various tissues of infected laboratory animals.
A molecular phylogeny of the genus Echinococcus
Authors: Bowles J. , Blair D. , McManus D. P. 
Published: June 2009

SUMMARYThree nucleotide data sets, two mitochondrial (COI and ND1) and one nuclear (ribosomal ITS1), have been investigated in order to resolve relationships among species and strains of the genus Echinococcus. The data have some unusual properties in that mitochondrial heteroplasmy was detected in one strain of E. granulosus, and more than one class of ITS1 sequence variant can occur in a single isolate. The data failed to support the hypothesis that E. granulosus, as it is currently viewed, is a single valid species. Rather, the strains of E. granulosus seem to comprise at least three evolutionarily diverse groups, the sheep strain group, bovine strain group and horse strain group. Molecular distances between them are comparable to, or greater than, molecular evolutionary distances observed between recognized species. The affinities of the cervid strain of E. granulosus are unclear because of ambiguous data, but this strain does not appear to be ancestral to others. E. multilocularis may not be distinct from E. granulosus. However, the remaining two species, E. vogeli and E. oligarthrus appear distinct and rather distant from the first two. Based on the results presented here, taxonomic revision of the genus is clearly warranted.
Iron status of schoolchildren with varying intensities ofTrichuris trichiurainfection
Authors: Ramdath D. D. , Simeon D. T. , Wong M. S. , Grantham-McGregor S. M. 
Published: June 2009

SUMMARYThe relationship between varying intensities ofTrichuris trichiurainfection and iron status was examined in Jamaican schoolchildren, aged 7 to 11 years. A total of 409 children was identified withT. trichiura(epg > 1200). A control group comprised 207 uninfected children who were matched by school and class to every pair of infected subjects. Blood samples were obtained from 421 children: 264 infected and 157 controls. Compared to the rest of the children, those with heavy infections (epg > 10 000) had significantly lower (P< 0·05) Hb (11·5 ± 1·3vs. 12·1 ± 1·1 g/dl), MCV (78·6 ± 6·3vs. 81·2 ± 5·5 fl), MCH (26·2 ± 2·9vs. 27·5 ± 2·5 pg) and MCHC (33·2 ± 1·5vs. 33·9 ± 1·4 g/dl). Similarly, the prevalence of anaemia (Hb < 11·0 g/dl) amongst heavily infected children (33%) was significantly higher (P< 0·05) than the rest of the sample (11%). These differences remained significant after controlling for confounding variables including socio-economic status, age, gender, area of residence and the presence ofAscarisinfections. Differences in red cell count, ferritin, and free erythrocyte protoporphyrin were not statistically significant and showed no association with the infectious load. These results suggest that in the Jamaican children studied, iron deficiency anaemia is associated withTrichurisinfections over 10 000 epg, but not with less intense infections.
Clinical and pathological effects of Echinostoma revolutum (Digenea: Echinostomatidae) in the golden hamster, Mesocricetus auratus
Authors: Huffman Jane E. , Michos C. , Fried B. 
Published: June 2009

SUMMARYLaboratory hamsters (Mesocricetus auratus) were infected with Echinostoma revolutum (Trematoda). Hamsters developed marked and sometimes fatal echinostomiasis. Clinical signs included progressive unthriftiness, watery diarrhoea and weight loss. Packed cell volume, haemoglobin and red blood cell counts increased in those animals with severe diarrhoea. No increase in eosinophils was noted in peripheral blood smears. Examination of tissues of infected animals showed wide individual variations related to the intensity of infection. The histopathological responses of hamsters to the parasite showed erosion of intestinal villi with lymphocytic infiltration being the primary response. Periportal lymphocytic infiltration and focal hepatic necrosis were observed in livers from some infected animals. The findings of this study are discussed in terms of variations in pathogenicity of E. revolutum and as a model for the study of echinostomiasis.
The population dynamics of metacercariae of Apatemon gracilis (Trematoda: Digenea) in three species of lake-dwelling leeches
Authors: Spelling S. M. , Young J. O. 
Published: June 2009

SUMMARYMonthly samples of the leeches Erpobdella octoculata, Glossiphonia complanata and Helobdella stagnalis were taken over a two-year period from an eutrophic, English lake to detect metacercariae of the trematode, Apatemon gracilis. In each cohort of each of the three leeches, prevalence was low in young individuals, rose to a peak in autumn/winter, and then declined until the cohort had almost died out; in E. octoculata and H. stagnalis a final brief increase occurred. Mean intensity and relative density values followed a similar seasonal pattern of change to that of prevalence in these last two species, but in G. complanata values fluctuated irregularly with no distinct pattern. The frequency distribution of the parasite in G. complanata was highly over-dispersed, but less so in the other two species. Infected E. octoculata reached sexual maturity. The parasite reduced egg production in G. complanata and H. stagnalis, but only by maximum values of 2·5 and 9% respectively. This reduction in fecundity is low compared to the subsequent high mortality, at 95% or more, of newly recruited young from as yet unidentified causes. Parasite-related host mortality was difficult to assess in young leeches, but there was some evidence for its occurrence in older leeches of E. octoculata and H. stagnalis. However, this is unlikely to play a prominent role in the control and regulation of lacustrine leech populations.
Physiological and behaviour changes in common lizards parasitized by haemogregarines
Authors: Oppliger A. , Célérier M. L. , Clobert J. 
Published: June 2009

SUMMARYThe effect of haemoparasites on the physiology and behaviour traits of their hosts was examined using Haemogregarina sp., a parasite of the common lizard, Lacerta vivipara, from the south of France. Infection with haemogregarines was associated with a reduced haemoglobin concentration and an increased number of immature red blood cells. Parasitized individuals also showed a reduced oxygen consumption at rest and a lower locomotor speed. We also found that the multiplication rate of the parasite depended on the temperature at which the lizard was maintained. Between 21 and 28 °C the multiplication rate of the parasite was significantly lower than between 29 and 35 °C. This suggests that the parasites may suffer reproductive costs when hosts reduce their body temperature.
Use of species-specific satellite DNAs as diagnostic probes in the identification of Steinernematidae and Heterorhabditidae entomopathogenic nematodes
Authors: Grenier E. , Bonifassi E. , Abad P. , Laumond C. 
Published: June 2009

SUMMARYThree satellite DNAs previously isolated from the entomopathogenic nematodesSteinernema carpocapsae, Heterorhabditis bacteriophoraandHeterorhabditis indicusgive hybridization signals only with theS. carpocapsae, H. bacteriophoraandH. indicuspopulations tested, indicating that these satellite sequences are species-specific. Because of their reiteration and their variabilities, we have shown that these sequences are able to discriminate at the interspecific level between theSteinernemaandHeterorhabditisspecies, but also at the intraspecific level betweenS. carpocapsaestrains. Furthermore, in simple squashed nematode experiments, we are able to unambiguously identifyS. carpocapsae,H. bacteriophoraandH. indicuspopulations. This last procedure is effective even on a single infective juvenile, with the main advantage that it avoids time-consuming DNA extractions.
Schistosoma mansoni: evidence that eosinophils and/or macrophages contribute to skin-phase challenge attrition in vaccinated CBA/Ca mice
Authors: Ward Rosalind E. M. , McLaren Diane J. 
Published: June 2009

SUMMARYNaive CBA mice and mice vaccinated 4 weeks previously with gamma-irradiated cercariae were challenged percutaneoualy with normal cercariae and the skin site of challenge removed at various times to provide samples for histological examination. Neutrophil abscesses surrounding schistosomula as well as cast cercarial tails were identified at the skin surface in both naive/challenged and vaccinated/challenged mice. The dermis in both groups of animals became infiltrated with mononuclear cells and granulocytes. Neutrophils were the predominant granulocyte in naive/challenged skin but eosinophils replaced neutrophils by 48 h post-challenge in skin from vaccinated mice. Schistosomula with adherent mononuclear cells and granulocytes were identified preferentially in the dermis of vaccinated mice; such larvae frequently exhibited subtegumental vacuolation. A further major characteristic of vaccinated/challenged skin was the formation, from 18 h, of extensive subdermal inflammatory foci, consisting of up to 50% mononuclear cells and 50% eosinophils. These foci invariably surrounded one or more larval parasites which were seen by both optical and scanning electron microscopy to have a morphology typical of lung stage rather than skin stage schistosomula. Dead, infiltrated parasites were also recognized within the subdermal foci. Our data support the view that vaccine immunity in this mouse model is mediated primarily in the skin and indicate that challenge attrition involves immobilization and killing of larval parasites by effector cells within subdermal inflammatory foci.
Antibody isotype responses to antigens ofAscaris lumbricoidesin a case-control study of persistently heavily infected Bangladeshi children
Authors: Palmer D. R. , Hall A. , Haque R. , Anwar K. S. 
Published: June 2009

SUMMARYAntibody responses toAscaris lumbricoidesworm antigens were examined by ELISA in a case-control study of 2 groups of Bangladeshi children, one of which had been shown over a period of 12 months to be consistently lightly infected (controls) and the other consistently heavily infected (cases). The children showed a wide range in intensity of infection; children identified as cases were on average 4 times more heavily infected than the controls. There were no significant differences in weight, height, mid-upper arm circumference and skinfold thickness between the case or control subjects at the time blood samples for analyses by ELISA were collected. Children with repeatedly heavy infections withA. lumbricoideshad higher concentrations of antibody isotypes to the antigens ofA. lumbricoidesthan children who are repeatedly lightly infected. IgG1, IgG4 and IgE to worm antigens occurred in significantly higher concentrations in heavily infected subjects. This suggests that these antibody responses simply reflect the intensity of infection and may not play a significant role in protecting against heavy infections.
Migration and development of the blood fluke Sanguinicola inermis Plehn, 1905 (Trematoda: Sanguinicolidae) in carp, Cyprinus carpio L
Authors: Kirk R. S. , Lewis J. W. 
Published: June 2009

SUMMARYThe migration and development of Sanguinicola inermis in carp fingerlings were investigated by quantitative analysis of serial sections of fish and examination of flukes from hosts up to 90 days p.i. Cercariae penetrated through the epidermis and migrated through connective tissue and muscle to establish in the blood system and commence egg production within 28 days p.i. Most flukes established in the ventral blood system and released eggs which accumulated in gill epithelial tissue. A minority of flukes inhabited dorsal blood vessels and shed eggs which lodged in connective tissue and visceral sites. Maximum life-span of the parasite is between 56 and 70 days p.i. and egg production peaked at day 42 p.i.