bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nutrition of the miteUnionicola intermedia, Koenike and its relationship to the inflammatory response induced in its molluscan hostAnodonta anatina, L.
Authors: Baker R. A. 
Published: June 2009

SummaryThe structure and staining properties of the epithelium of the midgut inUnionicola intermediaare described. Intracellular non-specific esterase, acid and alkaline phosphatase are present and confined to vacuoles. Extracellular enzymes are absent. Nymphal and adult stages ofU.intermediafeed principally on the haemocytes (= amoebocytes) and mucus of their molluscan host,Anodonta anatina. Feulgen-positive material recorded from the lumen and midgut cells of the mites is believed to be derived from the nucleated haemocytes and to undergo intracellular digestion in the midgut cells. Starved mites show steadily decreasing amounts of Feulgen-positive material in the vacuoles. Haemocytes are present in large numbers below the site of attachment of the mites, their presence represents an inflammatory response, and the mite feeds on the products of this response. Large amounts of bound iron are present in the midgut cells but the origin and role of this is unknown.
Tracking radioactive larvae ofStrongyloides rattiin the host
Authors: Wilson P. A. G 
Published: June 2009

SUMMARYInfective larvae of homogonicStrongyloides rattigrown in faecal culture with32P or75Se acquired a significant amount of radioactivity which was firmly attached to them. Heating removed most of the32P but left75Se in place. Subcutaneous injection of virgin and nursing mother rats with living and heat-killed radioactive larvae resulted in a pattern of labelling in the small intestine of injected animals and, in the case of75Se, those of suckling pups, which can only be explained if labelled worms follow the natural migratory routes. The use of this tool in migratory studies is discussed, with precautions to allow for flaws in the technique.
Prevalence of Trypanosoma cobitis Mitrophanow, 1883 in fishes from the River Lee
Authors: Letch C. A. , Ball S. J. 
Published: June 2009

SUMMARYThe prevalence of Trypanosoma cobitis was recorded in species of small fish from the River Lee at Enfield Lock during 33 months of sampling. Trypanosome infections were more numerous during the summer months with 50–70% of bottom-living ‘inactive’ fish, bullheads (Cottus gobio), stone loach (Nemacheilus barbatulus) and gudgeon (Gobio gobio) infected, compared to only 6 and 18% of the more active pelagic fishes, stickle-backs (Gasterosteus aculeatus) and minnows (Phoxinus phoxinus).
Survival characteristics of the free-living cercarial population of the ectoparasitic digenean Transversotrema patialensis (Soparker, 1924)
Authors: Anderson R. M. , Whitfield P. J. 
Published: June 2009

The survival characteristics of free-living cercarial populations of Transversotrema patialensis were described and shown to be age-dependent. The maximum life-span was found to be 44 h with a 50% survival at 26 h. Activity and infectivity of the larvae were also characterized by age-dependence, and were demonstrated to be closely correlated with one another. For individual cercariae, both activity and infectivity had dropped to extremely low levels many hours before death occurred. An attempt was made to interrelate activity and infectivity, in a theoretical manner, with the availability of energy reserves.Conceptual understanding of the biological processes involved was aided by the formulation of simple mathematical models.
Parasite population biology and host nutrition: dietary fructose and Moniliformis (Acanthocephala)
Authors: Keymer Anne , Crompton D. W. T. , Walters D. E. 
Published: June 2009

SUMMARYExperiments were carried out to investigate the possible influence of host-dietary fructose concentration on the relationship between worm burden and the fecundity of Moniliformis dubius. Worm length was found to be dependent both on the fructose concentration of the host's diet and on worm burden. The number of free ovaries/female worm was found to increase linearly with increasing dietary fructose concentration but was independent of worm burden. The length of the ovaries increased with increasing dietary fructose concentration and decreased in response to increases in worm density. The magnitude of the density-dependent reduction in the volume of ovarian tissue/female was decreased in worms from rats fed on diets containing low concentrations of fructose. The numbers of eggs present in the body cavities of the female worms was found to be positively correlated with dietary fructose concentration. At 5 weeks post-infection, mature eggs (containing fully developed acanthor larvae) were found in the body cavities of female worms from rats whose diets contained 3 and 12% fructose, but not in those from rats whose diets contained 1 and 2% fructose (w/w). The experimental results are discussed in the wider context of the influence of host nutrition on parasite population biology.
A comparative study of the life-histories of mammalian schistosomes
Authors: Loker Eric S. 
Published: June 2009

SUMMARYAvailable data in the literature pertaining to the life-history characteristics of all known species of mammalian schistosomes have been gathered, and correlations between such variables as length of pre-patent period, adult worm size, rate of progeny production and progeny size have been explored. Accommodation of the schistosome life-cycle to the constraints imposed by certain host characteristics such as life-expectancy and size is discussed. Of the 23 known species of mammalian schistosomes, 20 species apparently rely to a major extent on relatively large-bodied and long-lived mammals such as primates, ungulates and proboscideans for their transmission. Only 1 species,Schistosomatium douthitti, is exclusively dependent on rodents for its transmission.S. douthittiattains maturity within its definitive host faster than any other mammalian schistosome, and is the only species known to be capable of producing viable eggs by facultative parthenogenesis. For all species of mammalian schistosomes, adult worm size, as estimated by female length, is positively correlated with the number of uterine eggs contained within the female (r= 0·682). For the 7 species for which data exist, rate of egg production/worm pair/day is positively correlated with uterine egg counts (r= 0·873) and inversely correlated with egg length (r= −0·787) and miracidium length (r= −0·953). Length of the pre-patent period is positively correlated with egg length (r= 0·503). With respect to the molluscan host, the number of cercariae produced by snails is positively correlated with the shell size of the snail (r= 0·657). For the 5 species for which data exist, the rate of egg production is inversely correlated with shell size of the intermediate host (r= −0·955) and the common logarithm of the number of cercariae produced (r= −0·893). Comparisons between species suggest that exceptionally low rates of cercariae production in the intermediate host may be compensated for by rapid rates of egg production in the definitive host, implying a degree of integration in the schistosome life-cycle not previously appreciated. Most species of mammalian schistosomes have long-lived definitive hosts, and snail hosts capable of producing many cercariae; compensatory relationships are therefore less obvious in such species. Additional quantitative data on all aspects of schistosome life-histories, particularly rate and duration of egg production, are needed to confirm or refute the relationships discussed above.
Circadian variation in the distribution ofHymenolepis diminuta(Cestoda) and 5-hydroxytryptamine levels in the gastro-intestinal tract of the laboratory rat
Authors: Cho C. H , Mettrick D. F. 
Published: June 2009

SummaryThe circadian migration ofHymenolepis diminutain the small intestine of the rat may be correlated with a circadian variation in 5-hydroxytryptamine levels present in worm tissue, in the intestinal lumen, in the intestinal mucosa, with the amount of food present in the small intestine and in arterial blood. The 5-HT and food levels in uninfected animals were also determined. The 16.00 h stage in the circadian cycle marks both the commencement of host feeding, followed by rising 5-HT levels in both worm and host tissues, and initiation of an anteriad migration of worm biomass. It was found that 5-HT levels in the intestine of parasitized animals were significantly higher than in the intestine of uninfected controls. This is the first report of circadian variation in mucosal and luminal 5-HT levels. The similarity in the circadian patterns of worm migration and worm luminal, mucosal and blood 5-HT levels were striking. Fasting eliminated the circadian rise in intestinal 5-HT levels and the worms did not migrate. Luminal 5-HT levels were significantly lower in fasted animals than in the comparable rats fedad libitum. When the intestine was ligatured at the pyloric sphincter, worm anteriad migration still occurred after feeding, indicating that the presence of exogenous food in the intestine is not a factor in the initial migration of the worms.
A life-cycle stage-specific antigen ofTheileria parvarecognized by anti-macroschizont monoclonal antibodies
Authors: Shapiro S. Z. , Fujisaki K. , Morzaria S. P. , Webster P. , Fujinaga T. , Spooner P. R. , Irvin A. D. 
Published: June 2009

SUMMARYFour monoclonal antibodies, raised against macroschizonts ofTheileria parva, were studied to characterize their antigen binding specificity. The indirect fluorescent antibody test showed that the antigen(s) recognized were present in the macroschizont stage of the parasite life-cycle but not in piroplasm, kinete or sporozoite stages. Immunoblot analysis of macroschizont stage antigens suggested that all four antibodies recognized the same antigen. This was a molecule which varied in molecular mass between different parasite stocks, ranging from 68000 to 95000 Da. The antigen was localized by immunoelectron microscopy to the surface of the intracellular macroschizonts.
The relationship between pathology and resistance to reinfection withSchistosoma mansoniin mice: a causal mechanism of resistance in chronic infections
Authors: McHugh S. M. , Coulson Patricia S. , Wilson R. A. 
Published: June 2009

SUMMARYThe development of resistance in mice to reinfection withSchistosoma mansoniwas recorded during an early chronic infection, and compared with hepatic portal pathological and vascular changes. The latter were assessed using a microsphere injection technique. The degree of acquired resistance was directly dependent on the patent worm burden and the time post-infection. Strong correlations were noted between the development of resistance and the appearance of parasite eggs in the lungs and spleens of infected hosts. Weaker associations were present between resistance and other aspects of the disease pathology, such as portal hypertension and organ weights. The appearance of injected microspheres in the lungs and spleens correlated well with the appearance of eggs in those organs and with the development of resistance. The levels of resistance had risen and microspheres were detected in the lungs, before the development of major extra-hepatic, porta-systemic collateral vessels. It is concluded that intra-hepatic vascular alterations may be a causal factor in the development of resistance, preventing the sequestration of migrating schistosomula in the liver. It is estimated that as much as 70–75% of the recorded resistance can be attributed to this immunologically non-specific mechanism.
Non-specific induction of increased resistance in mice toTrypanosoma congolenseandTrypanosoma bruceiby immunostimulants
Authors: Murray Max , Morrison W. I. 
Published: June 2009

SUMMARYAdministration of the immunostimulantsCorynebacterium parvum, Bacillus Calmette-Guérin(BCG) orBordetella pertussisprior to, or at the same time as, challenge withTrypanosoma congolensesignificantly increased survival times in mice, both of trypano-susceptible (A/J) and trypano-resistant (C57Bl) strains. The increased survival time was associated with significant alterations in parasitaemia, which included lengthening of the pre-patent period, a delay in the time taken to reach the first peak of parasitaemia and a reduction in the level of parasitaemia. Similar results were obtained when these strains of mice were challenged withTrypanosoma bruceifollowing pre-treatment withC. parvum. Thus, by the use of immunostimulants it was possible to reduce the susceptibility of mice to trypanosomiasis and the hope is that this can also be achieved with domestic livestock.
The blocking of human antibody-dependent, eosinophil-mediated killing ofSchistosoma mansonischistosomula by monoclonal antibodies which cross-react with a polysaccharide-containing egg antigen
Authors: Dunne D. W. , Bickle Q. D. , Worth A. E. Butter , Richardson B. A. 
Published: June 2009

SUMMARYThree IgM monoclonal antibodies, M22G11P, M7B7 and M22B3G, which reacted with the surfaceof Schistosoma mansonischistosomula in an indirect fluorescent antibody assay, were found to recognize a polysaccharide-containing egg antigen previously designated K3. The monoclonal antibodies and a monospecific rabbit anti-K3serum also recognized a crossreacting antigen in a crude cercarial antigen preparation. In an eosinophil-mediated schistosomulum killing assay, all three monoclonal antibodies significantly inhibited the level of killing produced by human infection serum. An IgG3 monoclonal antibody, M22C1C, which also recognized the egg antigen K3, did not inhibit eosinophil-mediated killing. However, when lower concentrations of human serum were used in the assay, this monoclonal antibody significantly enhanced the level of killing, despite having no capacity to induce eosinophil-mediated damage in the absence of human infection serum. On the basis of these and other results we suggest the possibility that antibodies toS. mansoniegg antigens which cross-react with the surface of the early post-penetration schistosomulum may influence the effective expression of antibody-dependent, eosinophil-mediated effector mechanisms in human infections.
Reevaluation of the potential ofFasciola hepaticaantigens for immunization againstSchistosoma mansoniinfection
Authors: Ford M. J. , Taylor M. G. , Bickle Q. D. 
Published: June 2009

SUMMARYPrevious workers have reported that significant resistance toSchistosoma mansonicercarial challenge can be induced in mice by immunization with variousFasciola hepaticaantigen preparations. We have attempted to reproduce these observations and have also carried out similar experiments in rats. In our hands, however, CBA mice did not develop either antibodies against the schistosomular surface, or significant resistance to challenge after immunization with heterologous antigens. Similar results were obtained in Fischer rats, but rats did develop significant resistance after immunization with homologous (schistosomular) antigens, even without adjuvant, and the homologous ‘protective’ antigens could be separated by antibody-affinity chromatography using serum from rats vaccinated with irradiated cercariae. Thus, we found no evidence for the existence of shared ‘protective’ antigens betweenS. mansoniandF. hepatica, and suggest that this is further evidence that where heterologous resistance can be demonstrated between these two parasites, it is probably due to immunologically non-specific mechanisms.
Solubilization and immunoprecipitation of125I-labelled antigens fromPlasmodium knowlesischizont-infected erythrocytes using non-ionic, anionic and zwitterionic detergents
Authors: Howard R. J. , Barnwell J. W. 
Published: June 2009

SUMMARYPlasmodium knowlesimalaria-infected erythrocytes were radio-iodinated and several non-ionic, anionic and zwitterionic detergents were compared in their capacity to extract the labelled membrane proteins. The use of these detergents for antigen identification was tested by immunoprecipitation, after addition of Triton X-100 to some detergent extracts, using hyperimmune monkey antiserum and protein A-Sepharose.125I-labelled antigens were specifically immunoprecipitated with all detergents tested, including the anionic detergents sodium dodecyl sulphate (SDS), deoxycholate and cholate; the zwitterions Zwittergent-312 and -314, CHAPS and Empigen BB, as well as several non-ionic detergents. The SDS-polyacrylamide gel electrophoresis patterns of125I-labelled antigens varied after extraction with different detergents, there being no consistent pattern for detergents of a particular class. A total of 14125I-labelled antigens were identified, 11 of them using Triton X-100. Some minor antigens identified with Triton X-100 were immunoprecipitated in greater amount after extraction in other detergents. Most importantly, two antigens Mr200000 and 180000 were detected only after extraction with deoxycholate or SDS.
The development of the tegument and cercomer of the polycephalic larvae (cercoscolices) ofParicterotaenia paradoxa(Rudolphi, 1802) (Cestoda: Dilepididae) at the ultrastructural level
Authors: MacKinnon Barbara M. , Burt M. D. B. 
Published: June 2009

SUMMARYThe development of the tegument and cercomer ofParicterotaenia paradoxapolycephalic larvae was examined using electron microscopy. Larvae are formed by budding from the inner surface of the tegument of the degenerating hexacanth embryo. A new secondary tegument formed around the larvae is probably produced from the original hexacanth sub-tegumental cells. Microvilli covering the surface of young larvae are converted directly into microtriches, as the larvae develop, by addition of electron-dense material to the proximal part of the microvillus. Remnants of the original microvillus are visible at the distal surface of each new microthrix, but they eventually degenerate. The cercomer homologue is represented by scattered follicular cells, bearing microvilli, lying just within the containing cyst wall. The continuity of tegumentary tissue from one developmental stage to the next is discussed.
Nippostrongylus brasiliensis: the effect of mitochondnal inhibitors on life-cycle stages
Authors: Fry M. , Jenkins D. C. 
Published: June 2009

SUMMARYThe effects of mitochondrial inhibitors on the in vitro development of Nippostrongylus brasiliensis have been studied in free-living and parasitic life-cycle stages. Mitochondrial inhibitors were chosen as being representative of established electron transport inhibitors and oxidative phosphorylation inhibitors and uncouplers of the classical mammalian respiratory chain. All mitochondrial inhibitors tested were highly effective in killing or retarding development of free-living stages of N. brasiliensis. Free-living stages were particularly susceptible to such inhibitors upon hatching of embryonated eggs to 1st-stage larvae. Concentrations of inhibitors effective against free-living stages were consistent with their level of inhibition against isolated mitochondria from embryonated eggs and 3rd-stage infective larvae. Results suggest an absolute requirement in the development of free-living stages for the mammalian-like respiratory chain and associated oxidative phosphorylation. Electron transport inhibitors were effective in retarding at least the initial development of 4th-stage larvae to adults, but only antimycin A and azide produced a lasting effect leading to worm death. Oxidative phosphorylation inhibitors and uncouplers were ineffective against developing parasitic stages of N. brasiliensis. Experiments on whole-worm respiration indicated that most electron transport inhibitors were able to penetrate the adult worm, but oxidative phosphorylation inhibitors were without effect on whole-worm respiration. Results suggest that the mammalian-like electron transport chain is a necessary requirement to adult N. brasiliensis, but oxidative phosphorylation in the adult worm may not be required for development and survival in vitro although it could be necessary to support the parasite in vivo.
Hammondia heydorniinfection in sheep, goats, moose, dogs and coyotes
Authors: Dubey J. P. , Williams C. S. F. 
Published: June 2009

SUMMARYThe transmission ofHammondia heydorniamong sheep, goats, cattle, dogs and coyotes is described. Oocysts ofH. heydorni, obtained from dog faeces by feeding naturally infected goat meat, were fed to an experimental goat. After 312 days tissues from this animal were fed to 2 dogs. One dog, which received goat muscle, shed oocysts, whereas the other dog which received brain, spleen, kidneys, lungs and liver did not. Oocysts from the dog fed goat muscle were fed to an experimental sheep. After 73 days sheep tissues were fed to a dog and a coyote, both of which shed oocysts 5–8 days later. A second isolate ofH. heydorniwas obtained by feeding naturally infected beef to a coyote. These oocysts were fed to a single goat and sheep and after 71 days, muscle from these 2 animals was fed to 2 dogs and 2 coyotes, all of which shed oocysts 5–8 days later. None of the animals inoculated withH. heydornibecame ill and noHammondia-like organisms were found in tissue sections from the herbivores. Another dog shedH. heydorni-like occysts between 7 and 10 days after ingesting naturally infected muscles from a moose. These results indicate thatH. heydorniinfects goats, sheep, moose and coyotes in addition to cattle and dogs.
The isolation and characterization of human and bovine strains of Babesia divergens from Drumnadrochit, Scotland
Authors: Lewis D. , Purnell R. E. , Shaw S. R. , Revington J. P. 
Published: June 2009

SUMMARYStrains of Babesia divergens of human and bovine origin were isolated from the same locality in Scotland. A morphometric comparison was then made between Babesia divergens parasites in blood smears made from groups of 3 splenectomized calves reacting to the inoculation of these strains. The various forms taken by the parasites of each strain were seen to be divisible into 7 categories and representatives of each category were found for each strain. More amoeboid forms were found in blood smears from calves infected with the strain of bovine origin but otherwise the frequencies of occurrence of different forms coincided. The dimensions of 3 forms of the parasites of each strain were compared and theparasites of human origin were found to be significantly larger. The reactions of the groups of calves to inoculation of the 2 strains of B. divergens were seen to be very similar, although inoculation of the bovine strain had a slightly greater effect on the animals' haematology as indicated by an increase in erythrocyte mean corpuscular volume.