bluuebunny/crossref_metadata_2025_split huggingface dataset:
The impact of schistosomiasis on human nutrition
Authors: Stephenson L. 
Published: June 2009

SUMMARYThis article reviews studies that examine the negative effects of urinary and intestinal schistosomiasis on the following nutritional parameters in humans: urinary and faecal blood and iron loss, anaemia and haemoglobin levels, proteinuria, child growth and adult protein-energy status, physical fitness, physical activity, appetite and symptomatology. The conclusions reached are (1) that community-level treatment and control of schistosomiasis in areas where the infection, protein-energy malnutrition, and anaemia are common are to be encouraged and are likely to improve child growth, appetite, physical fitness and activity levels and to decrease anaemia and symptoms of the infection, and (2) that further studies are needed to determine how much and by what means decreases in and treatment of schistosomal infection may improve nutritional status, cognitive and school performance and attendance, and work capacity and productivity in communities with different amounts of parasitism and malnutrition.
Mutational and functional analysis of theLeishmaniasurface metalloproteinase GP63: similarities to matrix metalloproteinases
Authors: McMaster W. R. , Morrison C. J. , Macdonald M. H. , Joshi P. B. 
Published: June 2009

SUMMARYThe major surface glycoprotein ofLeishmania, referred to as GP63, is a zinc metalloproteinase of 63000Mrpresent on promastigotes and amastigotes from diverse species ofLeishmania. GP63 shares several characteristics with the members of the matrix metalloproteinase family including degradation of at least one component of the extracellular matrix, location at the cell surface, requirement for Zn2+for proteinase activity and inhibition of the proteinase activity by chelating agents and α2–macroglobulin. Site-directed mutagenesis of the clonedL. major GP63genes was carried out to determine whether the proposed active site ofLeishmaniaGP63 was homologous to those of other zinc metalloproteinases. The codon encoding the catalytic glutamic acid was modified to encode an aspartic acid and when expressed in COS–7 cells the resulting mutant GP63 had no demonstrable proteinase activity compared to wild type GP63. GP63 was predicted to be synthesized as a precursor protein containing a pro region at the NH2–terminus of GP63 implicated to be involved with the regulation of proteinase activity. As with many other proteinases, including matrix metalloproteinases, these enzymes are synthesized as latent proteinases that require activation for full proteinase activity.L. majorrecombinant GP63 (rGP63) has been produced in the baculovirus expression system whererGP63 was secreted as a latent proteinase. To study the activation of baculovirusrGP63, purifiedrGP63 was incubated with the mercurial compound, HgCl2, at concentrations previously shown to result in activation of other latent matrix degrading metalloproteinases and resulted in a significant enhancement of GP63 proteinase activity. The similarity of GP63 to the family of matrix-degrading proteinases suggests that the proteinase activity of GP63 maybe involved with the pathology of lesion formation in the mammalian host and may also be involved with the promastigote life stage in the sandfly vector. To study the functional role of GP63 proteinase, mutant strains ofL. major, deficient in the expression of GP63, are currently being derived by targeted gene deletion. Using this strategy results have demonstrated the deletion of an entireL. major GP63locus, containing in total sixGP63genes. Strategies to delete the secondGP63gene locus are developed and will determine whether deletion of both loci results in viable promastigotes.L. majorstrains deficient in the expression of GP63 may then be used to address the function of GP63 glycoprotein in the life cycle ofLeishmania.
Glycosyl-phosphatidylinositol molecules of the parasite and the host
Authors: Ferguson M. A. J. , Brimacombe J. S. , Cottaz S. , Field R. A. , Güther L. S. , Homans S. W. , McConville M. J. , Mehlert A. , Milne K. G. , Ralton J. E. , Roy Y. A. , Schneider P. , Zitzmann N. 
Published: June 2009

SUMMARYThe glycosyl-phosphatidylinositol (GPI) protein-membrane anchors are ubiquitous among the eukaryotes. However, while mammalian cells typically express in the order of 100 thousand copies of GPI-anchor per cell, the parasitic protozoa, particularly the kinetoplastids, express up to 10–20 million copies of GPI-anchor and/or GPI-related glycolipids per cell. Thus GPI-family members dominate the cell surface molecular architecture of these organisms. In several cases, GPI-anchored proteins, such as the variant surface glycoprotein (VSG) of the African trypanosomes, or GPI-related glycolipids, such as the lipophosphoglycan (LPG) of the Leishmania, are known to be essential for parasite survival and infectivity. The highly elevated levels and specialised nature of GPI metabolism in the kinetoplastid parasites suggest that the GPI biosynthetic pathways might be good targets for the development of chemotherapeutic agents. This article introduces the range of GPI structures found in protozoan parasites, and their mammalian hosts, and discusses some aspects of GPI biosynthesis.
Inhibition by anti-malarial drugs of haemoglobin denaturation and iron release in acidified red blood cell lysates – a possible mechanism of their anti-malarial effect?
Authors: Gabay T. , Krugliak M. , Shalmiev G. , Ginsburg H. 
Published: June 2009

SUMMARYIntraerythrocytic malaria parasites ingest the cytosol of their host cell and digest it inside their acid food vacuoles. Acidified (pH 4–5·5, 37 °C) human red blood cell lysates were used to simulate this process, measuring the denaturation of haemoglobin (Hb) and the release of iron, in the absence or presence of exogenous protease. Spontaneous Hb denaturation and appearance of non-heme iron were observed upon lysate acidification, their rates decreasing with increasing pH, and increasing in the presence of protease. Both processes were inhibited by the quinoline-containing anti-malarial drugs (QCDs) chloroquine, quinine, mefloquine and amodiaquine at concentrations well below those expected in the acidic food vacuole of the parasite. Spectrophotometric analysis indicated that chloroquine complexes with heme in acid-denatured haemoglobin. Other weak bases as well as verapamil and diltiazem, known to reverse the resistance of malarial parasites to chloroquine, were without efifect indicating that the action of QCDs is specific. Based on our previous results and the present report, we suggest that iron release in acidified lysates is mediated through the formation of ferryl (Fe(IV)) radicals. QCDs possibly complex with this radical, as they do with heme, and prevent its contact with an adjacent heme molecule which is required for ring opening and iron release. These results may suggest that one of the anti-malarial effects of QCDs is to deprive the parasite of an adequate iron supply. Addition of iron to cultures ofPlasmodium falciparumwas expected to circumvent the deprivation of iron and reduce the anti-malarial eflfect of QCDs. However, adding iron as penetrating fructose or nitrilotriacetate complexes did not alter the parasite's susceptibility to chloroquine. Ascorbate markedly increased the release of iron in acidified lysates, and this effect was not reduced by chloroquine. Ascorbate was found to decrease parasite susceptibility to chloroquine, suggesting that iron deprivation may be an important factor in the anti-malarial action of QCDs.
Sarcocysts (Sarcocystis sp.: Sporozoa) in the European badger, Meles meles
Authors: Odening K. , Stolte M. , Walter G. , Bockhardt I. , Jakob W. 
Published: June 2009

SUMMARYSarcocysts from the tongue muscle of a European badger (Meles meles) are reported for the first time and described by light and transmission electron microscopy. Judging from the ultrastructure of the cyst wall, the parasite is similar to the species Sarcocystis gracilis Rátz, 1909 sensu Erber, Boch & Barth (1978) from roe deer and possibly identical with it. This is noteworthy regarding the intermediate host specificity.
Temporal changes in Trichuris trichiura infection intensity and serum isotype responses in children
Authors: Needham C. S. , Lillywhite J. E. , Didier J. M. , Bianco A. E. , Bundy D. A. P. 
Published: June 2009

SUMMARYThe present study describes Trichuris trichiura infections in a cohort of children over a period of approximately 5 years, and examines the relationships between changes in infection intensity and changes in parasite-specific isotype responses (measured by ELISA). The decrease in mean infection intensity with time was mirrored by time-dependent changes in IgG subclass responses, with IgA and IgE levels remaining relatively constant in the cohort. At the individual level, changes in infection intensity between the initial and final time-points correlated positively and significantly with changes in all isotype levels with the exception of IgA.
Endogenous superoxide dismutase activity in two Babesia species
Authors: Becuwe P. , Slomianny C. , Valentin A. , Schrevel J. , Camus D. , Dive D. 
Published: June 2009

Parasitology, 105, 177–182page 180:The picture used for Fig. 2 represents isoelectrofocusing of B. divergens lysates.The picture used for Fig. 3 represents isoelectrofocusing of B. hylomysci lysates.
Addendum
Authors: Petkevicius S. , Bjørn H. , Roepstorff A. , Nansen P. , Knudsen K. E. Bach , Barnes E. H. , Jensen K. 
Published: June 2009

The effect of two types of diet on populations of Ascaris suum and Oesophagostomum dentatum in experimentally infected pigs Parasitology (1995), 111, 395–402Part of the reference list that was omitted from p. 402 appears below.
Further additions to the British records of acephaline gregarines of earthworms
Authors: Segun A. O. 
Published: June 2009

Five species of acephaline gregarine parasites – Apolocystis pilosa Meier from Lumbricus castaneus, L. festivus, L. rubellus and L. terrestris, Monocystis arcuata Boldt from L. castaneus, Nematocystis gracilis Berlin (= N. anguillula var. gracilis) from L. castaneus and L. rubellus, Zygocystis cometa Stein from Allolobophora caliginosa and Z. eiseniae Loubatieres from Eisenia foetida – identified during the present work are new to the British record.The characteristics of two other monocystids, N. lumbricoides Hesse and N. lumbricoides var. pilosa Meier are identical apart from the presence of short ectoplasmic hairs on the latter trophozoite's body. Since the presence of ectoplasmic hairs which are projections on the trophozoite's body is often utilized in gregarine speciation, the hairy and the hairless monocystids should be described separately.Berlin (1924) identified N. anguillula var. gracilis from the seminal vesicles of Lumbricus terrestris, L. rubellus and L. castaneus. This trophozoite should have been described as a separate species, N. gracilis Berlin and not as a variety of a totally different species originally described by Hesse (1909) from a host, Pheretima rodericensis, a megascolecid oligochaete, not found in Europe.The writer wishes to express his sincere appreciation to Dr Anne Terry for her advice and useful suggestions, and to Mr D. Etherington, the head of department, for his encouragements throughout this research period.
Detection and species identification ofCryptosporidiumoocysts using a system based on PCR and endonuclease restriction
Authors: Awad-El-Kariem F. M. , Warhurst D. C. , McDonald V. 
Published: June 2009

SUMMARYThe polymerase chain reaction (PCR) was used to produce a 556 bp nucleotide stretch, employing primers based on the published sequence of the 18S rRNA genes inCryptosporidium parvumandC. muris. This sequence was found to contain 3MaeI endonuclease restriction sites, 1 of which was present only inC. parvum. Mae I restriction of PCR products from 2C.parvumisolates (one of human origin and the other of bovine origin), 1C. murisisolate, and 1C. baileyiisolate, showed a specific and reproducible profile forC. parvumthat was different from the one obtained for bothC. murisandC. baileyi. From these data, newMaeI restriction maps were proposed for the three species. The system was then used to screen 6C. parvumisolates (from human and bovine hosts), and theC. parvum-specific profile was obtained for all isolates examined. It should be possible to adapt this protocol to detect small numbers ofC. parvumoocysts in environmental samples (e.g. in water supplies).
The effect of Trichinella spiralis and Trichinella pseudospiralis on the mechanical properties of mammalian diaphragm muscle
Authors: Winter M. D. , Ball M. L. , Altringham J. D. , Lee D. L. 
Published: June 2009

SUMMARYThe isometric mechanical properties of diaphragm muscle were studied in mice infected with either Trichinella spiralis or Trichinella pseudospiralis. Measurements of muscle stress were taken at 15, 20, 30 and 40 days post-infection. Infected diaphragm muscle showed a significant (P < 0·001) reduction in muscle stress during both twitch and tetanic contractions when compared with muscle from control animals. T. spiralis caused a significant reduction in resistance to muscle fatigue. The consequences of these changes in muscle function to host pathology are discussed, and related to previous work on the effects of Trichinella on host biochemistry and the immune response.
Hydrogen peroxide is the most toxic oxygen species forOnchocerca cervicalismicrofilariae
Authors: Callahan H. L. , Chouch R. K. , James E. R. 
Published: June 2009

SUMMARYThe toxicity of the active oxygen species hydrogen peroxide, superoxide radical, hydroxyl radical and singlet oxygen to microfilariae (mf) has been studiedin vitro, using active oxygen-generating systems and scavengers/inhibitors. Mf viability was monitored by uptake of the radiolabel, [3H]2-deoxy-D-glouse. Hydrogen peroxide and singlet oxygen, but not superoxide radical or hydroxyl radical, are toxic for mf. Hydrogen peroxide was toxic for mf within 2 h at concentrations as low as 5 ¼, an amount eosinophils have been shown to releasein vitro(Weisset al.1986). Catalase and thiourea, but not inactivated catalase, superoxide dismutase (SOD), singlet oxygen scavengers, or hydroxyl radical scavengers, protected mf. Mf have relatively high levels of endogenous SOD but no measurable glutathione peroxidase and low levels of catalase when compared with other parasites (Callahan, Crouch & James, 1988). The low levels of hydrogen peroxide-scavenging enzymes correlate well with mf sensitivity to hydrogen peroxide and the protective effect of exogenous catalase.
A quantitative study of the susceptibility of cockroach species to Moniliformis moniliformis (Acanthocephala)
Authors: Moore J. , Crompton D. W. T. 
Published: June 2009

SummaryWe exposed 19 species of cockroaches to Moniliformis moniliformis by administering shelled acanthors orally and by injecting hatched acanthors directly into the body cavity. The exposure method had little influence on susceptibility: with one exception, species that were susceptible to oral exposure were also susceptible to injected acanthors and, in no case, did acanthors develop in injected animals when they did not develop in orally exposed conspecifics. We found no support for the hypothesis that the intestine may be a barrier to M. maniliformis establishment in cockroaches. There is, however, clear interspecific variation in susceptibility to M. moniliformis infection.
A positive correlation between population size and egg-content in Metastrongylus apri (Gmelin, 1790)
Authors: Dixon J. B. 
Published: June 2009

SUMMARYObservations on the egg-content of 78 counted populations of Metastrongylus apri showed that there was a positive correlation between population size and mean egg-content per female. In bilateral infections within one host, a significant tendency was shown for the larger of the two populations to outstrip the smaller in mean egg-content per female. There was no correlation between sex-ratio and mean egg-content. It is suggested that the effect of the host's defences against individual parasites is mitigated when large numbers of parasites are present.A positive correlation was found between the sex-ratios of populations in left and right lungs, and there was a significant predilection of M. apri for the right lung.I am indebted to Dr S. Peto, Microbiological Research Establishment, Porton, Wilts, for statistical advice, and to T. Wall and Sons Ltd., Atlas Road, London, N.W. 10, for access to abattoir material.
Weight changes in chickens placed on different levels of nutrition and varying degrees of repeated dosage with Ascaridia galli eggs
Authors: Ikeme M. M. 
Published: June 2009

SUMMARYThe effect of continuing ingestion of eggs of A. galli on growth rates of chickens placed on different nutritional levels was studied under repeated doses of 10, 100 and 1000 infective eggs/day. With increasing amounts of protein in feed, there occurred significant weight differences between infected groups, the highest protein levels showing the longest duration in weight depression due to infection. On the other hand, assuming adequate nutrition of host, highest effects on growth rates were seen in chickens receiving daily doses of 1000 eggs daily and the lowest in chickens receiving 10 eggs daily.The effect of repeated dose on growth rate is similar to the effect of single infections reported by previous workers except that the duration of the growth depression was much longer in the former due to pathogenic effects of inhibited larvae.The author is indebted to the Department of Technical Cooperation, under whose Fellowship this study was carried out; to the Department of Zoology, Edinburgh University, where the work was done; to the Ministry of Agriculture, Fisheries and Food; Poultry Research Laboratories, Lasswade, for the free supply of chickens used here; and finally to Dr J. A. Campbell of Edinburgh University for his keen interest and advice throughout this work.
The chemical composition and some properties of the egg layers in Hymenolepis diminuta eggs
Authors: Lethbridge R. C. 
Published: June 2009

SUMMARY1. It has been shown that the protein eggshell of Hymenolepis diminuta eggs was not significantly stabilized by sulphur or electrovalent linkages but was resistant to attack by proteolytic enzymes. Amino acid analysis demonstrated a marked preponderance of aromatic and heterocyclic acids and it has been suggested that these groups act as cross-linking agents in the shell protein.2. The role of the lipid-containing subshell ‘membrane’ in protecting the enclosed embryo against fluctuations in pH and osmolarity in the external environment and infiltration of enzymes and toxic compounds has been demonstrated.3. The cytoplasmic layer was shown to consist of a glucosamine-containing mucoprotein present in a dehydrated or semi-dehydrated state in the intact egg.In mechanically damaged eggs the cytoplasmic layer was rapidly dispersed by some proteolytic enzymes.4. The embryophore enclosing the hexacanth embryo was composed of a sulphurrich protein that was weakened by some proteolytic enzymes and completely destroyed by others.I should like to thank Professor T. R. E. Southwood, in whose department this work was carried out, and Dr June Mahon for her advice and encouragement.I am particularly grateful to Dr R. A. Wilson, Department of Biology, University of York, for the quantitative amino acid determinations on eggshell hydrolysates and for criticizing this manuscript. This research was conducted during the tenure of a Science Research Council Studentship and formed part of a thesis submitted for the Ph.D. degree, University of London.
Antigenic variation in Babesia rodhaini demonstrated by immunization with irradiated parasites
Authors: Phillips R. S. 
Published: June 2009

SUMMARY1 Populations of Babesia rodhaini were isolated which were ‘putative’ variants of a reference population.2. They were shown to have some antigenic dissimilarity to the reference population by comparing the response of rats immunized with irradiated parasites of the reference population, to challenge with either the reference population or with the variant populations. To the homologous challenge the immunized rats were strongly resistant. After a heterologous challenge, however, for the first 3 or 4 days the immunized rats showed no resistance but thereafter rapidly controlled the infection.3. Five ‘variation’ populations were tested and all were shown to have some antigenic dissimilarity to the reference population. Two variant populations were compared and were not found to be identical with each other. There appeared, however, to be less dissimilarity between them and any one variant and the reference population.Mrs J. Page and her successor Miss D. Leader, gave technical assistance. I thank my colleagues for helpful criticism of the manuscript.
Carbohydrate/lectin interactions between the nematophagous fungus,Arthrobotrys oligospora, and the infective juveniles ofTrichostrongylus colubriformis(Nematoda)
Authors: Wharton D. A. , Murray D. S. 
Published: June 2009

SUMMARYRemoval of the sheath of the ensheathed infective juvenile ofTrichostrongylus colubriformisprevents capture by the nematophagous fungusArthrobotrys oligospora. Exposure of the trap hyphae to a variety of saccharides, which may block a recognition system based on lectin/carbohydrate binding, failed to prevent capture but some saccharides did inhibit penetration and invasion by the fungus. Capture and penetration thus appear to be two distinct processes with capture being less specific than penetration. Carbohydrate residues were absent from the outer surface of the cuticle and the sheath but were present on the inner surface of the sheath. The limited accessibility of these lectin-binding sites may explain the slow process of infection of the infective juvenile by the fungus. The sheath does not protect the infective juvenile against attack by this nematophagous fungus.
Beta-oxidation in the free-living stages of the entomophilic nematodeRomanomermis culicivorax
Authors: Gordon R. , Walsh D. J. , Burford I. R. 
Published: June 2009

SUMMARYAll of the enzymes involved in the β-oxidation pathway were identified from juvenile and adult postparasites of the mermithid nematodeRomanomermis culicivorax. The postparasites readily took up exogenous [14C-U]palmitate and oxidized it to CO2, indicating that the β-oxidation pathway is functional. The extent to which this pathway is utilized during the natural cycle of the nematode is discussed.
Host protective humoral immune responses to Schistosoma mansoni infections in the rat. Kinetics of hyperimmune serum-dependent sensitivity and elimination of schistosomes in a passive transfer system
Authors: Mangold Beverley L. , Knopf P. M. 
Published: June 2009

SUMMARYA passive transfer system, dependent upon hyperimmune rat serum, was used to study in vivo protective humoral immunity to Schistosoma mansoni infection in Fischer rats. Infected recipients of hyperimmune serum exhibited a significant reduction (51%) in the number of recovered adult schistosomes relative to infected recipients of normal rat serum. Furthermore, schistosomula were equally sensitive to the effects of hyperimmune serum injected up to and including 7 days post-infection, a phenomenon which was termed ‘extended sensitivity’. Schistosomula were beginning to lose sensitivity to the effects of hyperimmune serum by the 8th day post-infection and were completely refractile by the 9th day. In addition, it was demonstrated that parasite elimination occurred after the lung stage. Some protection was also observed when hyperimmune rat serum was transferred to mice as late as 5 days post-infection.