bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunocytochemical demonstration of a neuropeptide in Ascaris suum (Nematoda) using an antiserum to FMR Famide
Authors: Davenport T. R. B. , Lee D. L. , Isaac R. E. 
Published: June 2009

SUMMARYA FMRFamide-like peptide has been detected in the nematode Ascaris suum, using the peroxidase-anti-peroxidase (PAP) immunocytochemical technique. Positive reactions were obtained in both the central nervous system and the peripheral nervous system of the worm, the strongest reactions being in the anterior nerve ring, the cephalic papillary ganglia, the lateral ganglia and the dorso-rectal ganglion. Immunoreactivity was observed along the length of the main nerve cords of the worm and, to a lesser extent, in the pharyngeal nerve cords. The possible role of this neuropeptide in the physiology of the nematode is discussed.
Immune evasion bySchistosoma mansoni: loss of susceptibility to antibody or complement-dependent eosinophil attack by schistosomula cultured in medium free of macromolecules
Authors: Dessein A. , Samuelson J. C. , Butterworth A. E. , Hogan Maureen , Sherry Barbara A. , Vadas M. A. , David J. R. 
Published: June 2009

SUMMARYSchistosomula ofSchistosoma mansoni, recovered either after penetration of cercariae through isolated rat skin or by mechanical transformation of cercariae, become fully resistant after 24–48 h of culture to damage by human blood eosinophils in the presence of human anti-schistosomular sera. Cultured schistosomula are also shown to lose their susceptibility to attack by human eosinophils in the presence of human complement. This resistance is related to the simultaneous reduction of the ability of human anti-schistosomular antibodies and human complement component C3 to bind to the surface of the cultured larvae. The development of insusceptibility to antibody, complement and eosinophil-mediated attack does not require the acquisition by the schistosomula of a protective coat of host or other macromolecules, since it is achieved in chemically defined culture medium free of serum and macromolecules. This supports the hypothesis that schistosomula undergo intrinsic changes which render them insusceptible to immune attack.
The effects of vector control on the antibody response to antigens ofOnchocerca volvulus
Authors: Bradley J. E. , Gillespie A. J. , Trenholme K. R. , Karam M. 
Published: June 2009

SUMMARYThe effects of exposure to infective larvae on the antibody response to a cocktail of specific recombinant antigens ofOnchocerca volvulusand to a worm extract were evaluated by comparing the responses of individuals from a vector controlled area with those from an area of continuing transmission by ELISA. Individuals from the vector controlled areas were found to have reduced responses to both antigen preparations. Amicrofilerdermic (mf–) individuals from the area of vector control exhibited significantly lower total and subclass IgG responses to the worm extract. In contrast, the responses to the cocktail of specific recombinants were significantly reduced in individuals from the area of vector control who were still microfilerdermia positive (mf+). The distribution of IgG subclass specific responses was similar to both antigen preparations, both dominated by the IgG4 and IgG1 subclasses. IgG1 responses to the worm extract remained elevated in the vector controlled individuals but IgG4 was significantly reduced in the mf – individuals. Both subclasses reflected the total IgG response to the cocktail of recombinants and were significantly reduced in individuals from the vector controlled area, when compared to individuals from the hyperendemic area. IgG1 responses to the cocktail of recombinants are significantly lower than IgG4 in all individuals and virtually absent in individuals from the vector-controlled area. Measuring total IgG and IgG4 is more sensitive than IgG1 in detecting infection, 100 or 97% respectively, but they remain elevated in the individuals from the vector controlled areas even after 8–10 years interruption of transmission. These results have important implications for the serological monitoring of control programmes in individuals who have previously been infected.
Cloning, over-expression and evaluation of a recombinant fusion protein ofWuchereria bancroftitowards its application as a diagnostic agent for bancroftian filariasis
Authors: Theodore J. G. , Kaliraj P. , Jayachandran S. , Jayaraman K. 
Published: June 2009

SUMMARYA low molecular weight (15 kDa) surface antigen of the cattle filarial nematode,Setaria digitata, was earlier shown to be specifically recognized by the antibodies from human bancroftian filarial (Mf positive) patients' sera (Theodore & Kaliraj, 1990). The filarial specific antibodies bound to a 15 kDa peptide in preparative Western blots were eluted and employed in screening of candidate antigens expressed in the genomic library ofWuchereria bancroftiat the IgG4subclass antibody level. A recombinant clone (λ WbG7) reacting strongly with filarial sera but poorly with sera from patients infected with non-filarial helminths was selected for further studies. The 2 kb DNA insert of the clone λ WbG7 was recloned into a pMAL vector and the recombinant clone pGT7 thus obtained was over-expressed and affinity purified. The purified 105 kDa fusion protein of the clone pGT7 was specific and was not recognized by the non-filarial sera at the IgG4level. All microfilaraemic individuals were positive by IgG4assay. However, similar attempts to diagnose by filarial-specific IgE assays failed to recognize microfilaraemic individuals. Moreover, by filarial-specific IgG4assays, the endemic normals were distinctly divided into two groups, showing higher and lower recognition for this antigen indicating current and past/no infection. Among the filarial-IgG4(assay)-positive ‘endemic normals’, 14% showed ‘microfilariae’ during repeated peripheral night blood examination, confirming the validity of the recombinant antigen, pGT7 based assay.
Tumour necrosis factor-α and macrophages inPlasmodium berghei-induced cerebral malaria
Authors: Curfs J. H. A. J. , Hermsen C. C. , Kremsner P. , Neifer S. , Meuwissen J. H. E. Th. , Rooyen N. Van , Eling W. M. C. 
Published: June 2009

SUMMARYThe effect of tumour necrosis factor-α on malaria-infected mice was studied. C57B1/6J mice infected withPlasmodium bergheiK173 exhibited an increased sensitivity to exogenous TNF. Injection of 15 μg TNF was lethal to some of the animals when given 5–7 days after infection, while when given later on in the infection (i.e. days 8–10) amounts as low as 2·5 μg TNF appeared to be lethal in all mice. The pathology in infected mice treated with TNF resembled that found in the brains of infected mice dying with cerebral malaria. Infected mice treated with TNF, however, also developed severe pathological changes in other organs. On the contrary, treatment with sublethal amounts of TNF (1·0 μg or less) given on days 8 and 9 after infection, protected mice against the development of cerebral malaria. In addition, infected mice exhibited an enhanced sensitivity for treatment with lipopolysaccharide (LPS). Sublethal amounts of LPS, however, did not prevent mortality as in TNF-treated mice (LPS-treated mice died at about the same time as infected mice that developed cerebral malaria), but no cerebral haemorrhages were found in the majority of LPS treated, infected animals. Treatment with dexamethasone during infection protected mice against the development of cerebral malaria, but did not suppress their increased sensitivity to exogenous TNF. Treatment of mice with liposome-encapsulated dichloromethylene diphosphonate (lip-Cl2MDP), used to eliminate macrophages (an important source of TNF), prevented the development of cerebral malaria, but only when given before day 5 of infection. Mice protected by treatment with lip Cl2MDP, however, remained sensitive for LPS on the eighth day of infection.
Effects of methotrexate on the parasitic development of the nematode Dictyocaulus viviparus (Metastrongylidae), and on the immune response of infected guinea-pigs
Authors: Wilson R. J. M. 
Published: June 2009

Methotrexate inhibited the growth of D. viviparus by acting either on the moult from the third- to the fourth-stage larva or on the growth of fourth-stage larva itself. Despite these effects of the drug, the early developmental stages of the worms primed the immune mechanism of the host; the inductive phase of antibody production was completed in less than 5 days. An effective immune response, however, was blocked by the continued presence of methotrexate which resulted in delayed elimination of a superinfection and the absence of anaphylactic antibody in the serum. Immune elimination appeared to require a quantitative threshold of worm antigen and host antibody.This work was made possible by the generous supply of infective helminth material from Messrs Allen and Hanbury Ltd, Ware, Herts. I should also like to thank Dr J. H. Humphrey and Dr S. R. Smithers of N.I.M.R. for their helpful discussions.
Developmental stages in the Digenea
Authors: Byrd Elon E. , Maples William P. 
Published: June 2009

The naturally oviposited egg ofDasymetra confertais fully embryonated and it hatches only after it is ingested by the snail host,Physaspp.Hatching appears to be in response to some stimulus supplied by the living snail. The stimulus causes the larva to exercise a characteristic series of body movements and to liberate a granular sustance (hatching enzyme) from the larger pair of its cephalic glands. This enzyme reacts with the vitelline fluid to create pressure within the egg capsule, and with the cementum of the operculum, so that it may be lifted away. The larva's escape from the shell, therefore, is due to a combination of pressure and body movements.The hatched larva has a membranous body wall, supporting six epidermal plates, an apical papilla, two penetration glands and a central matrix (the presumptive brood mass).It lives for about an hour within the snail and during this time there is a reorganization of the central matrix which terminates in the formation of an 8-nucleated syncytial brood mass.The miracidial ‘case’, consisting of the body wall and the epidermal plates, ultimately ruptures to liberate the brood mass. Once the brood mass is free it penetrates through the gut wall in an incredibly short time.
A freeze-fracture study of the cuticle of adult Nippostrongylus brasiliensis (Nematoda)
Authors: Lee D. L. , Wright K. A. , Shivers R. R. 
Published: June 2009

SUMMARYThe surface of the cuticle of adult Nippostrongylus brasiliensis has been studied by means of the freeze-fracture technique and by transmission electron microscopy. Some of the surface coat appears to have been shed from the surface of the cuticle of adults fixed in situ in the intestine of its host and from the surface of individuals removed from the intestine and freeze-fractured. Freeze-fracturing the cuticle of individuals removed from the host has shown that this surface coat varies in thickness from 30 to 90 nm. The epicuticle is about 20 nm thick and cleaves readily to expose E- and P-faces. The P-face of the epicuticle possesses a small number of particles, similar to intra-membranous particles, whilst the E-face possesses a few, widely scattered depressions. Despite the presence of these particles the epicuticle is not considered to be a true membrane. Freeze-fracturing the remainder of the cuticle has confirmed its structure as described by conventional transmission electron microscopy. Clusters of particles on the P-face of the outer epidermal (hypodermal) membrane and corresponding depressions on the E-face of the membrane are thought to be associated with points of attachment of the cuticle to the epidermis (hypodermis). No differences in appearance of the cuticle and its surface layers were observed in individuals taken from 7-, 10-, 13- and 15-day infections.
Single juveniles of the potato cyst nematodes Globodera rostochiensis and G. pallida differentiated by randomly amplified polymorphic DNA
Authors: Roosien J. , Van Zandvoort P. M. , Folkertsma R. T. , Rouppe Van Der Voort J. N. A. M. , Goverse A. , Gommers F. J. , Bakker J. 
Published: June 2009

SUMMARYRandom amplified polymorphic DNA (RAPD) offers a potential basis for the development of a diagnostic assay to differentiate the potato cyst nematode species Globodera rostochiensis and G. pallida. Nine decamer primers have been tested for their ability to amplify species-specific DNA sequences. Primer OPG-05 produced 2 discrete DNA fragments, which were consistently present in 5 G. rostochiensis populations and absent in 5 G. pallida populations. These fragments were detectable in single females as well as in single 2nd-stage juveniles. Their amplification is extremely efficient, and reproducible over a wide range of template concentrations. One-fifth of a single juvenile is sufficient to generate reproducible RAPD markers. The amplification from single juveniles requires no DNA isolation. The use of a crude homogenate does not impair the polymerase chain reaction.
Studies on the amphid specific glycoprotein gp32 in different life-cycle stages of Meloidogyne species
Authors: Stewart G. R. , Perry R. N. , Wright D. J. 
Published: June 2009

SUMMARYIndirect immunofluorescent studies have been used to localize a glycoprotein (gp32) in the amphids of 2nd-stage juveniles (J2) of Meloidogyne incognita parasitic in the roots of tomato plants, male Meloidogyne javanica and some young adult female M. incognita. Immuno-electron microscopic studies showed an apparent absence of gp32 in the amphids of mature adult female M. incognita. Chemoattraction experiments demonstrated that the binding of gp32 antibodies to the amphidial secretions of infective J2 M. incognita partly impaired the ability of the nematodes to locate tomato roots.
Survival of Pseudodiplorchis americanus (Monogenea) under controlled environmental conditions
Authors: Tocque K. , Tinsley R. C. 
Published: June 2009

SUMMARYPopulations of Pseudodiplorchis americanus infecting the desert toad, Scaphiopus couchii, have previously been shown to be remarkably stable from year to year, despite wide variation in conditions promoting invasion. The present study aimed to document the survival of both first-year and pre-existing adults under controlled laboratory temperatures. First-year worm survival in experimentally infected toads was shown to be very high for the first 5 months after migration to the definitive site, and there was no difference in survival at 25 °C or 15–20 °C. There was also no density-dependent survival during the same period: 20% of worms were recovered from the host urinary bladder, irrespective of initial intensities. After the first 5 months, there was a progressive loss of worms in toads maintained at 25 °C but not at 15–20 °C. Pre-existing adult populations were shown to be virtually identical to those under natural conditions for the first 4 months after toad capture. Following this, at 25 °C, populations declined and no pre-existing adults were recovered after 11–14 months. There was no such loss of pre-existing adults at 15–20 °C for up to 14 months. A diurnal temperature cycle of 20–34 °C (simulating temperatures during the desert summer) did not lead to a significant loss of worms. These observations suggest that during one annual cycle in the desert, when temperatures remain above 20 °C for less than 6 months, most adult worms established in the host urinary bladder will survive to the next transmission opportunity. However, the similar longevity of first-year and pre-existing adults in laboratory maintained toads shows that loss of worms cannot be due solely to parasite ageing. Temperature-dependent survival of P. americanus is suggestive of a host immune response. Low temperatures, which inhibit parasite growth and development, are essential for the survival of P. americanus.
The control of trichostrongyle larvae (Nematoda) by fumigation in relation to their bionomics
Authors: Sturrock R. F. 
Published: June 2009

In a small-scale trial in which boxes of grass infested with Trichostrongylus colubriformis were treated with methyl bromide, a dose of 100 mg. hr./l. prevented guinea-pigs picking up the infection when they grazed the grass at a later date. A practical method is described for fumigating small areas of pasture. In a field trial, sheep were used to test plots of pasture fumigated with doses which did not kill the grass but the results were inconclusive. These experiments are discussed and also the possible value and applications of this technique.I am indebted to Professor B. G. Peters and to the other members of the Imperial College Field Station, particularly Dr A. B. Page and Dr O. F. Lubatti, for their help and criticism during the work. Thanks are also due to Dr William Davies, the Director of the Grassland Research Institute, Hurley, for permission to carry out the field experiment there, and also to Dr C. R. W. Spedding and Mr T. Brown for their co-operative assistance and advice throughout this work.
The migration ofCercaria XBaylis (Strigeida) within the molluscan intermediate hostLymnaea stagnalis
Authors: Probert Allan J. , Erasmus David A. 
Published: June 2009

The route of migration ofCercaria Xwithin the host snail,Lymnaea stagnalis, has been demonstrated by means of serial sections and a method of numerical assessment of the distribution of cercariae in the various tissues and organs of the body.The main pathway along which migrating cercariae travel is the blood system, which differs from the route in the fish second intermediate host. The cercariae enter the main visceral haemocoel by rupture of the wall of the digestive gland and from there enter the main venous vessels deploying through the rectal sinus, sub-renal sinus, lung and heart. The cercariae travel from the heart via the mantle arteries to localize in the mantle sinuses prior to emergence.The inner surface of the mantle, and in particular its leading edge, is the main site of emergence, and escape of cercariae is, in the final stages at least, an active process. It is suggested that passage of parasites in the blood stream is partly active.Migration and subsequent emergence is probably facilitated by the activity of the oral cap of spines, the general activity of the cercaria and the activity of the oral and ventral suckers.A tissue response to the presence of cercariae in the blood vessels and tissues of the mantle is evident, the cells responsible for this being, possibly, actively phagocytizing amoebocytes of the mollusc's blood. The swellings in the epidermis of the mantle in heavy infections may be the result of an accumulation of these cells.Grateful acknowledgement is expressed to Professor J. Brough for the facilities and encouragement provided during the course of this study. This work was carried out during the tenure by A. J. Probert of a D.S.I.R. Research studentship.
Studies on Demodex folliculorum Simon (1842). I. Life history
Authors: Spickett S. G. 
Published: June 2009

1. Histological data are given about the location and frequency of the different stages of the life history of D. folliculorum in the pilo-sebaceous apparatus of man. These data are examined statistically and the relative durations of each stage and their movements in the follicle are deduced from them.2. A method of in vitro culture is described and data are given about the longevity of the various stages of the life history.3. Experiments on the behaviour of the different motile stages of the mite are described. It is concluded that the deutonymph is the distributive stage, and that distribution occurs over the skin surface.4. The life history is reconstructed by a synthesis of the evidence presented. The life-cycle lasts approximately 14½ days, the life span of each stage of it being: ovum 60 hr., larva 36 hr., protonymph 72 hr., deutonymph 60 hr., adult 120 hr. Interval between copulation and oviposition 12 hr.This work was largely carried out in the Department of Pathology of the Institute of Dermatology, London, and I wish to thank the Director of Pathology, Dr J. O. Oliver, for making available to me the facilities of his department, and for his advice and interest during the progress of the work. The photographs were prepared by Mr R. H. Lunnan of the Photographic Department of the Institute of Dermatology. I am indebted to the Dean of the Institute of Dermatology for permission to publish the photographs.I am grateful to Mr T. E. Hughes of the Department of Zoology, Birkbeck College, University of London, for his advice at all times, and to Miss Hilda Davies of the Department of Statistics, University of Sheffield, for help with statistical methods and to Mr W. Moseley, who prepared the text figures.Finally, I wish to express my thanks to Professor I. Chester Jones and Dr E. T. B. Francis of the Department of Zoology, University of Sheffield, for reading the manuscript and for their help in its preparation.
The fine structure of the body wall of Polymorphus minutus (Goeze, 1782) (Acanthocephala)
Authors: Crompton D. W. T. , Lee D. L. 
Published: June 2009

The body wall of Polymorphus minutus has been studied with the electron microscope and the structure of the various layers has been described.The layers are the same in number as those seen with the light microscope, and pores have been found which penetrate the cuticle. Thus, the structure of the surface layers is such as would facilitate the absorption of nutrients.It has been found that the cuticle and striped layer extend over the trunk spines, a feature which increases the area of the absorptive surface of the parasite.The structure of the striped layer of the praesoma supports the theory that the praesoma body wall and lemnisci are involved in the absorption of fat.Mitochondria have been detected in the felt and radial layers of the body wall and in the circular and longitudinal muscles.The body wall of this acanthocephalan worm is entirely different from the body wall of trematodes, cestodes and parasitic nematodes.We are grateful to Dr P. Tate for helpful discussions, Dr R. J. Skaer for criticism of the manuscript and to Professor J. D. Boyd for permission to use the electron microscope in the Department of Anatomy. Thanks are also due to Mr A. J. Page for technical assistance.
Experiments with Trichostrongylus colubriformis (Giles, 1892) in the guinea-pig I. The effect of the host response on the distribution of the parasites in the gut
Authors: Connan R. M. 
Published: June 2009

The distribution of Trichostrongylus colubriformis in the intestine of the non-immune guinea-pig is described. At day 10 of the primary infection the majority of larvae were found in the anterior half of the small intestine with progressively smaller numbers in all parts of the gut posterior to this. However, soon after day 10 a migration of the worm population took place so that by day 15, before there had been a reduction in the total present, the majority of worms were found in the posterior small intestine. Thereafter the posterior movement continued, but while the numbers in the large intestine increased the movement then coincided with the beginning of the expulsion of the worms.By the irradiation of guinea-pigs prior to infection the posterior migration was prevented, indicating that the latter was the result of a host response.The independent migration of two generations of parasites was noted and two possible explanations are put forward.This work was carried out during the tenure of a Research Training Scholarship awarded by the Animal Health Trust.The author would like to thank Professor W. I. B. Beveridge in whose Department this work was carried out, and also Mr King of the Department of Radio-therapeutics, University of Cambridge, who irradiated the guinea-pigs used in Expt. 3.