bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eosinophilia in Kenyan baboons (Papio anubis) induced byTrichinella spiralisandSchistosoma mansoni
Authors: Sturrock R. F. , Butterworth A. E. , Karamsadkar S. D. , Kimani R. , Imbuga M. , Houba V. 
Published: June 2009

High primary doses ofTrichinella spiralisadministered orally to Kenyan baboons (Papio anubis) induced a marked but unpredictable eosinophilia which started 2–3 weeks after infection and persisted as erratic waves for at least 6 months. Low primary oral doses induced no eosinophilia but a later, high challenge gave an accelerated eosino-philic response, although the peak was lower than in high primary infection. Intravenous injection of infectiveT. spiralislarvae resulted in a predictable, rapid eosinophilic response which persisted for several weeks. Intravenous injection of a particulate material, Sepharose, gave no oesinophilic response.PercutaneousSchistosoma mansoniinfection of baboons resulted in a two-stage eosinophilic response: an initial rise occurred about ⅔ of the way through the pre-patent period and was followed by a second rise at the onset of patency. After peaking, the eosinophilia waned erratically over the next 3 or 4 weeks.A strong antibody response, measured by countercurrent imnruno-electrophoresis, was given in oral infections withT. spiralis, but intravenous injections elicited little or no antibody formation. Parasitological evidence indicated no cross-resistance toS. mansoniin baboons injected withT. spiralis9 days previously. Thus, the intravenous injection of infectiveT. spiralislarvae appears to be a suitable method of inducing experimentally a non-specific eosinophilia to investigate possible immune mechanisms toS. mansoniin the baboon.
Partial purification of antigens collected duringin vitrocultivation of the larval stages ofTaenia pisiformis
Authors: Rickard M. D. , Katiyar J. C. 
Published: June 2009

SummaryLarvae ofTaenia pisiformiswere culturedin vitroin medium containing 2·5, 5 or 20% (v/v) of normal rabbit serum (NRS). Greatest development occurred in 20% NRS, and the potency of antigens collected in medium from each culture tested by intradermal (i/d) skin tests in infected rabbits paralleled thein vitrogrowth rate of larvae. ‘Culture’ antigens from 5% NRS stimulated good immunity in rabbits to a challenge infection withT. pisiformiseggs, although they were poorly reactive in skin tests.T. pisiformislarvae were also cultured in 10% (v/v) of nitrates of serum reduced to one-half of its volume by passage through 300 000 MW cut oif (XM300F) or 100000 MW cut off (XM100F) ultrafiltration membranes. Larvae cultured using XM300F had growth rates comparable with those cultured in 20% NRS, and the antigens released into the culture medium had equal potency in i/d tests and in stimulating protective immunity in rabbits. Larvae did not develop in XM100F orproduce skin-reactive or protective antigens.Crude ‘culture’ antigen from cultures in 20% NRS was separated into 4 fractions by nitration on Sephadex G200. All of these fractions gave i/d skin reactions in infected rabbits. Fraction 3 (F3) was the most active, but was shown by acrylamide gel electrophoresis and immunoelectrophoresis to be highly contaminated with rabbit serum proteins. F3 was separated into fractions on DEAE-Sephadex A50, and the third fraction from this was as active as the original culture medium in i/d skin tests, but had only 5% of the original protein concentration. Electrophoresis demonstrated few serum contaminants, and 2 indistinct protein bands that were not present in a similar fraction of NRS.Neither Sephadex G200 F3 nor DEAE-Sephadex F3 stimulated protective immunity in rabbits, suggesting that antigens stimulating immunity against the establishment ofT. pisiformisin rabbits and those provoking cell-mediated immune reactions may be different.
Milk-borne infection of rats with Strongyloides ratti and Nippostrongylus brasiliensis
Authors: Wilson Peter A. G. , Gentle Maureen , Scott Douglas S. 
Published: June 2009

SummaryThe numbers of mature worms which developed in young rats after their mothers were injected with 4000 L3 late in lactation were 1% (Nippostrongylus brasiliensis) and 24% (Strongyloides ratti) of the dose administered. The low value for N. brasiliensis validates the conclusion that milk is a real and important vehicle for infection in S. ratti since possible errors from skin invasion of the young would have been common to both species.The level of mature S. ratti infection in lactating mothers in this experiment was negligible, 97–99% of the adult worms appearing in the offspring.These results may indicate that the milk route is possible with N. brasiliensis even though it is quantitatively insignificant.
Attrition and temporal distribution of Schistosoma mansoni and S. haematobium schistosomula in laboratory mice
Authors: Georgi J. R. , Wade S. E. , Dean D. A. 
Published: June 2009

SUMMARYThe total number and distribution of schistosomula of Schistosoma mansoni and S. haematobium in all tissues and organs of mice from infection to 14–27 days was determined by compressed tissue autoradiography. Attrition of schistosomula, manifested as a decrease in the number of autoradiographic foci, was observed in organs other than the liver. Attrition commenced about 2 days after cercariae entered the skin, and conformed to a single exponential function with a rate constant (± standard error) of 7·0±0·5%/day for S. mansoni and 3·2±0·7%/day for S. haematobium. The temporal distribution of schistosomula of S. mansoni and S. haematobium differed quantitatively. In the case of S. mansoni, concomittant with a decrease in skin counts, the lung curve rose rapidly to a peak centred on day 6 and thereafter decreased more or less parallel to the total body curve. Significant accumulation in the liver was not observed until day 7, whereupon liver counts rose steadily to a plateau that extended from about day 14 to the end of the experiment and approximated the number of adult worms recovered from the hepatic portal vessels on day 42. A maximum of 26% and mean of 12% of all foci in the body were counted on autoradiograms of tissues other than the skin, lung and liver. The pelt averaged 14% of the body weight yet schistosomula were detected only in the area initially exposed to cercariae. The eviscerated carcass averaged 54% of the body weight yet contained only 0·8% −3·4 % of the schistosomula during the period of accumulation in the liver. Between day 6 and day 14, the ratio of schistosomula in the pulmonary circulation to schistosomula in the systemic circulation did not remain constant, as would be the case if schistosomula circulated passively and randomly, but instead displayed a statistically significant decrease from 0·92 and 0·85. For these reasons, it was considered unlikely that schistosomula had circulated randomly and repeatedly through the pulmonary and systemic circulations and entered the hepatic portal system by chance, as hypothesized by Miller & Wilson (1980). Instead it was considered more probable that schistosomula migrating from lungs to liver had followed a directed path through intervening vessels (Kruger, Heitman, van Wyk & McCully, 1969) or tissues (Wilks, 1967). Schistosoma haematobium distribution patterns differed from those of S. mansoni in slower movement of schistosomula from skin, their peak accumulation in lungs at about day 8 followed by a low rate of decrease, and a very low liver plateau which approximated the number of adult worms recovered from the hepatic portal vessels on day 42.
Studies on the behaviour, and development in fish, ofSubtriquetra subtriquetra: a uniquely free-living pentastomid larva from a crocodilian
Authors: Winch Judith M. , Riley J. 
Published: June 2009

SUMMARYThe primary larva of the porocephalid pentastomidSubtriquetra subtriquetra, which infects the nasopharynx ofCaiman sclerops, is uniquely free-living. Eggs hatch within the nasal passages and the emergent larvae can remain infective to the fish intermediate host for 4–5 days. During this period larvae exhibit very stereotyped behaviour, alternating between a characteristic stationary ‘fishing’ posture and very brief periods of movement. Larval activity increases significantly at 3 days, probably effecting dispersal to a more favourable site for host invasion. Host location is passive and invading larvae penetrate to the swim-bladder where subsequent larval development, which involves 7 moults, occurs. All 8 larval stages are freely mobile in the swim-bladder and possess hooks. Sensilla, disposed in characteristic patterns, are present throughout development, increasing in number to the infective stage; the majority of sensilla are located on sensory papillae.
The seasonal occurrance of Trilocularia acanthiaevulgaris (Cestoda: Tetraphyllidea) from spiny dogfish in the Irish Sea
Authors: McCullough J. S. , Fairweather I. , Montgomery W. I. 
Published: June 2009

SUMMARYTrilocularia acanthiaevulgaris occurs in the stomach and spiral valve of the spiny dogfish. Statistical analyses show that the stomach and spiral valve worms of male fish and the stomach worms of female fish exhibit seasonal trends in prevalence and mean worm burden, with peaks occurring in May, June and July of each year. Spiral valve worms of female fish do not show this trend. Calculation of the product-moment correlation coefficient shows that the peak in the number of stomach worms occurs approximately 1 month before that of spiral valve worms in male fish. Strobilization of the adult spiral valve worms and development of the resulting free proglottides is also seasonal, and takes place in June/July in both sexes. Seasonal trends in prevalence, mean worm burden and maturation of T. acanthiaevulgaris may be related to water temperature, and the cyclical changes in levels of reproductive hormones and thyroid activity associated with migration and mating of spiny dogfish. It is suggested that the availability of infected intermediate hosts and diet of the dogfish may also be important in explaining the seasonality of infection.
Epidemiology of Heligmosomoides polygyrus in mice: experiments on natural transmission
Authors: Slater A. F. G. , Keymer A. E. 
Published: June 2009

SUMMARYAn experimental system is described for the study of the community dynamics of helminth–host populations, using Heligmosomoides polygyrus in the laboratory mouse. The results of a preliminary experiment using closed populations of 50 mice revealed that coexistence of host and parasite occurs for at least 4 months in the absence of immigration, with the generation of epidemiological patterns similar to those observed in the real world. In well-nourished mice the prevalence and intensity of infection initially increased with time and then declined, probably as a result of acquired immunity. The prevalence and intensity of infection increased less rapidly among hosts fed on a low protein diet, but continued to rise over the entire duration of the experiment. This continued rise is interpreted as evidence of a negative effect of protein malnutrition on host immunocompetence. The frequency distributions of parasite numbers/host were over-dispersed in each mouse population. No density dependence in parasite fecundity was detected. Aspiculuris tetraptera was also found to be present in the mouse populations. This parasite was not transmitted between mice fed on a high protein diet, but rose to a prevalence of 80 % in protein malnourished animals. No association between the intensity of A. tetraptera and H. polygyrus could be detected in individual hosts. The results are discussed in terms of the future potential of the system for the investigation of the role of acquired immunity (and its genetic control) in the generation of epidemiological patterns.
In vitroproliferative response to living schistosomula by T lymphocytes from mice infected withSchistosoma mansoni
Authors: James S. L. 
Published: June 2009

SUMMARYThe development of T cell reactivity toward schistosomula during murineSchistosoma mansoniinfection has been studied using an adaptation of thein vitrolymphocyte proliferation assay in which the response is elicited by exposure to living schistosomula. The reactivity measured in this system was shown to be a T lymphocyte function and to require the presence of adherent cells. This assay may therefore provide a new method for analysis of basic interactions between host cells and schistosomula. Lymph node cell responses were observed in two phases, the first of which appeared during the second week after infection, reflecting the immunogenicity of schistosome larval forms. A later, more pronounced response appeared during the chronic stage of infection, where sensitization appeared to be stimulated primarily by ongoing exposure to adult worms, rather than eggs. Lung-stage and skin-stage larvae elicited a similar degree of thymidine uptake by cells from chronically infected mice. Intact skin-stage larvae and particulate fractions provoked greater proliferation than soluble larval constituents, indicating that the lymphocyte response is directed in large part toward determinants which remain associated with the schistosomula during culture. However, the presence of major histocompatibility complex products on the membrane of lung-stage schistosomula did not influence the presentation of larval antigens to sensitized lymphocytes. The implications of these findings in immunity to schistosomiasis are discussed.
Epidemiology of East Coast fever: some effects of temperature on the development of Theileria parva in the tick vector, Rhipicephalus appendiculatus
Authors: Young A. S. , Leitch B. L. 
Published: June 2009

SUMMARYThe moulting behaviour of nymphal Rhipicephalus appendiculatus from the laboratory colony and 3 field strains from Kenya was greatly influenced by constant temperatures between 18 and 37 °C but was not significantly different for the 4 tick strains. Six batches of R. appendiculatus (Muguga laboratory) nymphs which had engorged on cattle parasitaemic with 4 stocks of Theileria parva (Kiambu 4, Kiambu 5, Muguga and Mbita 4) isolated in Kenya were incubated at constant temperatures between 18 and 37 °C during their pre-moult and post-moult periods. The Theileria infections in the salivary glands of the resultant adult ticks were assessed by staining with Feulgen's stain. Two stocks (Muguga and Kiambu 5) developed their highest infections in ticks incubated at 28 °C while the other two (Kiambu 4 and Mbita 4) developed their highest infections at 23 °C. Constant temperatures of 18, 33 and 37 ° C were detrimental to the development of salivary gland infections. Temperature influenced the rate of development and numbers of the earlier Theileria stages in the ticks. Engorged nymphal ticks incubated for 4 days at 37 °C during their pre-moult period developed lower infections than ticks exposed at 4 °C for 4 days.
The energy metabolism of adultHaemonchus contortus, in vitro
Authors: Ward P. F. V. , Huskisson N. S. 
Published: June 2009

SummaryA comparison was made of the major excretory products when adultHaemonchus contortusworms were incubated with D-[U-14C]glucose under aerobic and anaerobic conditions. Catabolites measured were propan-1-ol, acetate,n-propionate and CO2and the only major difference was that nearly twice as much CO2both in terms of quantity and radioactivity was excreted under aerobic than anaerobic conditions. The worms were also much more physically active under aerobic conditions. When worms were incubated under aerobic conditions with increasing amounts of fluoroacetate their CO2production was progressively reduced to the anaerobic level. Their movement and their ability to clump together was also progressively reduced. After aerobic incubation with fluoroacetate and D-[U-14C]g1ucose the quantity and radioactivity of citrate within worms increased greatly. When worms were similarly incubated anaerobically no increase in citrate occurred, no radioactivity was associated with the citrate and the worms appeared physically unaffected. When worms were incubated aerobically with fluoro[1-14C]acetate they produced radioactive fluorocitrate.
The identification of soluble adult antigen on the tegumental surface of juvenile Fasciola hepatica
Authors: Bennett C. E. 
Published: June 2009

SummaryAn antiserum was raised in rabbits against a soluble extract of fresh homogenized adult Fasciola hepatica of rat origin and was then absorbed with rat and mouse tissue antigens. This antiserum reacted specifically with the surface coat of adult flukes, of both rat and mouse origin, by indirect immunofluorescence to show the detail of surface spines. When tested against juvenile stages recovered from mice the reaction was positive with all but the earliest hepatic parenchyma stages. No reaction was present on the tegumental surface of newly excysted juveniles or stages 1 or 2 days post-infection (p.i.) whether recovered from the peritoneal cavity or the hepatic parenchyma.
Development of infectivity in Hyalomma detritum (Schulze, 1919) ticks infected with Theileria annulata (Dchunkowsky and Luhs, 1904)
Authors: Samish M. , Pipano E. 
Published: June 2009

SummaryThe time-course for the development of infectivity was studied in Hyalomma detritum ticks fed as pre-imagoes on calves infected with Theileria annulata. Unfed adults derived from infected nymphs were non- infectious when inoculated into susceptible calves, whereas ticks of both sexes that had fed for 2–3 days or longer on calves or rabbits were always infectious. Some adults fed for only 1–2 days were infectious, whereas others were not. As few as 2 ticks were capable of infecting susceptible calves.
Observations on the morphology and electrophoretic variation of enzymes of the rodent malaria parasites of Cameroon, Plasmodium yoelii, P. chabaudi and P. vinckei
Authors: Lainson F. A. 
Published: June 2009

SUMMARYSix samples of rodent blood infected with malaria parasites were isolated from Cameroon. Of these, 2 contained mixed infections of Plasmodium vinckei and P. yoelii, 3 contained P. vinckei alone and 1 P. chabaudi alone. Each isolate was cloned and the resulting lines examined for morphology of blood and mosquito forms, and for electrophoretic variation in enzymes. The P. chabaudi and P. yoelii lines were morphologically and enzymically identical to isolates of the Central African Republic. Similarly, 1 P. vinckei line was identical to an isolate of the Central African Republic. The remaining 4 P. vinckei lines showed considerable variation, some enzymes being like those in isolates of surrounding regions, while others were unique to Cameroon.
Gorgoderina vitelliloba: an ultrastructural study on the development of the tegument from the metacercaria to the adult fluke
Authors: Hoole D. , Mitchell J. B. 
Published: June 2009

SUMMARYThe tegument of the metacercaria of Gorgoderina vitelliloba contains S1, S2, S3 and S4 secretory bodies. Between the parenchymal cells 2 types of tegumental cyton occur. Type 1 contains S1 and S3 secretory bodies, whilst S2 and S4 bodies are limited to Type 2. Type 1 cytons and S1 secretory bodies disappear at excystment. Post-metacercariae contain a third type of tegumental cyton in which a new secretory body, S5, occurs. This cyton type disintegrates 1–5 days after infection. The maintenance and development of the outer anucleate layer after this period is the responsibility of Type 2 cytons. Type 2 cytons and S2 and S4 secretory bodies have also been found within the cercarial body. When juvenile flukes migrate from the kidney to the bladder of their frog definitive host 21 days after infection, the outer anucleate layer increases in electron density. Within the bladder, however, the tegument of the adult fluke appears normal. The distribution of mitochondria within the outer anucleate layer changes during the fluke's migration. The mitochondria, which have a random distribution in the metacercaria, are located adjacent to the outer and basal plasmalemmas in the early kidney stages. In late kidney stages and bladder stages mitochondria occur only against the former membrane. The mitochondria increase in size in the adult fluke.
Ultrastructural observations on thein vitrointeraction of rat neutrophils with schistosomula ofSchistosoma mansoniin the presence of antibody and/or complement
Authors: Incani R. N. , McLaren Diane J. 
Published: June 2009

SUMMARYRat peritoneal neutrophils adhere to schistosomula ofSchistosoma mansoni in vitroin the presence of antibody, complement, or both. Ultrastructural studies have demonstrated that cell adherence is not intimate, and that electron-dense secretions are not liberated onto the parasite surface in the manner described for eosinophils. Cytochemical techniques confirm that peroxidase is confined within intracellularly located neutrophil secretion granules. The metabolic burst is shown to operate during Fc-mediated interactions, but since morphological damage depends upon the presence of complement in the system, toxic oxygen products would seem not to be involved in the initiation of surface perturbation. Complement-dependent, neutrophil-mediated schistosomular damage is characterized by vesiculation of the tegumental outer membrane, an increase in density of the tegumental cytoplasm and the eventual development of focal lesions. The cells migrate laterally to push aside damaged surface tissues and then adhere intimately to the exposed musculature. Damage appears earlier when both antibody and complement are present in the system, and this correlates with higher killing efficiency. The frequently observed association of contaminant eosinophils with areas of parasite damage indicates that eosinophils and neutrophils may cooperate to effect schistosomular killing. In the presence of antibody alone, attached neutrophils exhibit intense phagocytic activity towards the antigen-antibody complex formed at the parasite surface. This phenomenon may account for the eventual detachment of cells and lack of significant parasite damage recorded in this system
Further investigation of the pathogenicity, immunogenicity and stability of precocious Eimeria acervulina
Authors: McDonald V. , Ballingall S. 
Published: June 2009

SUMMARYAttenuated lines of Eimeria acervulina were isolated between 62 and 72 h post-infection from the Houghton (H) strain. The inoculation of small numbers of oocysts of precocious (HP) lines gave substantial protection to Light Sussex chicks kept on litter against challenge with the virulent H strain. The precocious trait of the 72 h HP line was shown to be stable because the kinetics of oocyst production remained unaltered after 9 consecutive passages through birds in which only late developing oocysts were used for passage. The precocious 62 h HP line was subjected to further selection for 5 consecutive passages. The resultant (62 A HP) line was shown to be more attenuated than the 72 h HP line but remained capable of immunizing chicks against challenge with the H strain.
The use of plasma etching to reveal the internal structure of Nippostrongylus brasiliensis (Nematoda)
Authors: Lee D. L. , Nicholls C. D. 
Published: June 2009

SUMMARYPlasma etching has been used to strip away the cortical layers of the cuticle of adult Nippostrongylus brasiliensis to reveal the struts, with their supporting fibres, which are found in the fluid-filled middle layer of the cuticle, and the basal fibre layers. The etched specimens were studied by means of scanning electron microscopy. The results support earlier work, obtained by transmission electron microscopy, on the cuticle of this nematode. Plasma etching has been shown to have potential in studying the structure of nematodes.