bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of mononuclear-cell recruitment to the lungs in the development and expression of immunity toSchistosoma mansoni
Authors: Ratcliffe E. C. , Wilson R. A. 
Published: June 2009

SUMMARYThe role of pulmonary cellular responses in the induction and expression of immunity toSchistosoma mansonihas been evaluated. From experiments in which mice were challenged at intervals after vaccination, we conclude that the resistance mechanism operating in the lungs develops between days 11 and 20. Injection of51Cr-labelled splenocytes revealed that mononuclear cell recruitment to the lungs, stimulated by the arrival of attenuated schistosomula, intensified progressively between days 10 and 16 post-vaccination. The increased cellularity was reflected in a 19·5% augmentation in the wet-weight index (WW). The period of enhanced cell recruitment therefore coincided with the build-up of resistance. By day 22 post-vaccination infiltration had declined, whilst WW remained elevated. This indicates the persistence of recruited cells, which include schistosome-reactive T lymphocytes, in the lungs. We were unable to demonstrate augmented recruitment of51Cr-labelled cells after challenge of vaccinated mice, but WW rose slightly, peaking on day 12. Although clearly of a lower order than the primary response, the secondary response was more rapid, implying the existence of immunological memory. These results accord with the concept that schistosome-reactive T lymphocytes recruited after vaccination ‘arm’ the lungs against the arrival of challenge parasites.
A comparison of the sites of acid phosphatase activity in an adult filaria, Setaria sp. and in some gastro -intestinal nematodes
Authors: Maki Jun , Yanagisawa Toshio 
Published: June 2009

SUMMARYThe histochemical localization of acid phosphatase in an adult filaria, Setaria sp. obtained from the peritoneal cavity of a cow was closely examined and compared with that of adult nematodes parasitic in the host alimentary canal; special attention was paid to the intestine and body wall of the parasites. Setaria sp. was found to show high acid phosphatase activity in the interchordal hypodermis of the body wall and uterine microfilariae, and similar activity is suspected to occur in the cuticle. The intestine of this nematode exhibited very low, if any, activity. In contrast, nematodes parasitic on the alimentary canal, such as Toxocara cati, T. canis, Physaloptera sp. and Ancylostoma caninum, showed no activity in the body wall and very high activity in the luminal surface of their intestine. The possible function of the abundant acid phosphatase in the body wall of this filaria is discussed.
Prospects for the biological control of plant-parasitic nematodes
Authors: Tribe H. T. 
Published: June 2009

SUMMARYBiological control is understood here in the classical sense, which is precisely defined by De Bach (1964) as ‘the action of parasites, predators or pathogens in maintaining another organism's population density at a lower average than would occur in their absence’. This account consists of a survey of the principal causes of disease in nematodes, with a summary of the efforts made to use certain pathogens in practise and a discussion of nematode pathology with reference to destruction of plant pathogenic nematodes.
Characterization of buffalo-derived theilerial parasites with monoclonal antibodies and DNA probes
Authors: Conrad P. A. , Ole-Moiyoi O. K. , Baldwin C. L. , Dolan T. T. , O'Callaghan C. J. , Njamunggehr R. E. G. , Grootenhuis J. G. , Stagg D. A. , Leitch B. L. , Young A. S. 
Published: June 2009

SUMMARYThe characteristics of intra-lymphocyticTheileriaisolated from African buffalo and from cattle that were infected with buffalo-derived parasites were evaluated using anti-schizont monoclonal antibodies (mAbs) and DNA probes. Antigenic differences were revealed by the reactivities of 27 mAbs with the buffalo-derived parasites isolated from different animals. Antigenic diversity was also seen withTheileria-infected lymphoblastoid cell isolates taken from the lymph nodes and blood of the same animals. Two DNA probes, selected from a genomic library ofT. parvapiroplasm DNA cloned inλgt11, showed specific hybridization to parasite DNA in Southern blots of restriction enzyme-digested, lymphoblastoid cells infected with buffalo-derived theilerial parasites. Genotypic differences between the buffalo-derived parasites were revealed by the restriction fragment length polymorphisms seen with hybridization of those probes to DNA from cloned and unclonedTheileria-infected cell lines. The evaluation of theilerial parasites derived from buffalo and from cattle which underwent typicalT. p. lawrenceireactions, after being infected with buffalo-derived theilerial parasites, did not show any specific phenotypic or genotypic characteristics of these parasites that would distinguish them fromT. p. parvaandT. p. bovisparasites. The validity of these subspecies distinctions is discussed.
The prevalence and pathology of Schistosoma nasale Rao, 1933 in cattle in Sri Lanka
Authors: De Bont J. , Van Aken D. , Vercruysse J. , Fransen J. , Southgate V. R. , Rollinson D. 
Published: June 2009

SUMMARYDuring 1987 a total of 1393 cattle was examined for Schistosoma nasale infection at the Kandy slaughterhouse, Sri Lanka. The overall prevalence was 12·6% (monthly range 3–17%). Based on the appearance of macroscopic lesions, 6 types (0–5) were recognized; type 5 being the most severe, with cauliflower-like growths obstructing the nasal cavity. Older bovines with 8 permanent incisors were more heavily infected (29·%) than younger ones with no permanent incisors (6·0%). The severity of the lesions increased also with the age of the animals. Observations on the localization of the lesions showed that the first sessile nodular areas appear on the medial septum, on the dorsal edge of the ventral nasal concha and on the lateral wall of the middle meatus of the nasal cavity. Later, they gradually spread over the whole mucosal surface of the anterior part of the cavity but were rarely found further than 10 cm posterior to the nasal opening. The histopathology showed that granuloma formation due to the presence of eggs was the most common feature of the respiratory mucosa.
Ancylostoma ceylanicum in the hamster: observations on the host—parasite relationship during primary infection
Authors: Garside P. , Behnke J. M. 
Published: June 2009

SUMMARYThe course of primary infection with a hamster-adapted strain of Ancylostoma ceylanicum was studied in inbred DSN and randomly bred WO/GD and WO/CR hamsters. Infective larvae were administered orally and began to develop in the small intestine without embarking on a tissue migration. Only the occasional larva was detected in other organ sites. It was concluded that the developing larvae moulted on days 3–4 and again to the pre-adult stage about 9–11 days post-infection. Worm burdens in infected hamsters were stable for at least 11 weeks after infection. There was no sudden expulsive phase and some adult worms survived for over 200 days. Overall the sex ratio of worms in groups of hamsters killed concurrently was about 50% although occasionally the ratio was biased in favour of one sex in individual animals. The blood packed cell volume (PCV) was significantly depressed 2 weeks following infection and continued to decline until a point of stability was achieved 4–5 weeks post-infection. The PCV subsequently remained depressed throughout the period of observation. Infected hamsters lost weight if kept in groups, but not when housed in separate cages. Groups of animals which lost weight did not recover to normal values within 11 weeks of infection. It is suggested that this model of hookworm infection has scope for exploring aspects of the host-parasite relationship which the canine models cannot fulfill adequately.
Intra-erythrocytic death of the parasite in mice recovering from infection withBabesia microt
Authors: Clark I. A. , Richmond J. E. , Wills E. J. , Allison A. C. 
Published: June 2009

As mice recover from infection withBabesia microti, abnormal forms of the parasite are present in some red cells. These forms are non-infective, indistinguishable by light microscopy from those present after treatment with amicarbalide, a babesicidal drug, and persist in splenectomized mice.Electron microscopy confirmed that these abnormal forms are degenerating intra-erythrocytic parasites. In the absence of evidence for death ofB. microtielsewhere in the body, it appears that infections of mice with this parasite are normally terminated by their death within circulating red cells. This has important implications for the mechanism of immunity to both this parasite and thosePlasmodiumspp. with which it cross-protects in this host.
Frequency distribution of Brugia malayi microfilariae in human populations
Authors: Srividya A. , Krishnamoorthy K. , Sabesan S. , Panicker K. N. , Grenfell B. T. , Bundy D. A. P. 
Published: June 2009

SUMMARYThis study examines the effects of host age and sex on the frequency distribution of Brugia malayi infections in the human host. Microfilarial (mf) counts for a large data base on the epidemiology of brugian filariasis in Shertallai, Kerala, South India are analysed. Frequency distributions of microfilarial counts partitioned by age are successfully described by zero-truncated negative binomial distributions, fitted by maximum likelihood. This analysis provides estimates of the proportion of mf-positive individuals who are identified as negative due to sampling errors, allowing the construction of corrected mf age–prevalence curves, which indicate that the observed prevalence may under-estimate the true figures by between 18 and 47%. There is no evidence from these results for a decrease in the degree of over-dispersion of parasite frequency distributions with host age, such as might be produced by the acquired immunity to infection. This departure from the pattern in bancroftian filariasis (where there is evidence of such decreases in over-dispersion; Das et al. 1990) is discussed in terms of the long history of filariasis control (and consequently low infection prevalence) in Shertallai.
Potential interactions between Acanthocephalus anguillae and Pomphorhynchus laevis in their natural hosts chub, Leuciscus cephalus and the European eel, Anguilla anguilla
Authors: Bates R. M. , Kennedy C. R. 
Published: June 2009

SUMMARYChub and eels were experimentally infected via intermediate hosts harbouring cystacanths, with Pomphorhynchus laevis alone, or Acanthocephalus anguillae alone, or simultaneously with mixtures of both species in varying proportions, and sampled at 7, 56 or 112 days post-infection. Examination of chub revealed that both species showed low establishment and growth rates, differing markedly from British field data, where chub is apparently one of the most important hosts, and preventing further meaningful experiments. Both species showed higher establishment rates in eels, but A. anguillae both grew faster and matured to a greater extent than P. laevis, reflecting field data. No evidence of any interactions, competitive or otherwise, was found in the mixed infections in eels at low or high infection levels. The results were interpretated with regard to British field data and current theories of the role of interspecific competition in structuring fish helminth communities.
Characterization of the relationships in the pinewood nematode species complex (PWNSC) (Bursaphelenchus spp.) using a heterologous unc-22 DNA probe from Caenorhabditis elegans
Authors: Abad P. , Tares S. , Brugier N. , De Guiran G. 
Published: June 2009

SUMMARYPine wilt is the most serious disease of native pines in Japan and potentially the most important nematode disease of conifers in the world. The pinewood nematode Bursaphelenchus xylophilus was found to be the causal agent. Difficulties arose with respect to the precise identity of some isolates of B. xylophilus and of similar species B. mucronatus and B. fraudulentus. Restriction enzyme analyses of repetitive DNA revealed bands specific for the species B. xylophilus, B. mucronatus and B. fraudulentus. Hybridization patterns obtained with unc-22 gene of C. elegans, clearly identified B. xylophilus, B. mucronatus and B. fraudulentus as well as the different geographic isolates of these species. Furthermore, it is possible to define the phylogenetic relationships between the different populations constituting the ‘pine wood nematode’ complex.
Experimental studies on the life-cycle ofRaillietiella gigliolii(Pentastomida: Cephalobaenida) in the South American worm-lizardAmphisbaena alba: a unique interaction involving two insects
Authors: Winch Judith M. , Riley J. 
Published: June 2009

SUMMARYRaillietiella giglioliiis a cephalobaenid pentastomid which inhabits the lungs of the South American worm-lizardAmphisbaena alba. The host is a facultative inquiline of nests of the leaf-cutting antAtta cephaloteswhere it feeds occasionally (and possibly by accident) on ants but more often on beetles and their larvae which are themselves inquilines of ant nests. Ants store exhausted leaf-substrate in special underground chambers which serve as refuse dumps and it is here that larvae of the three-horned rhinoceros beetleCoetosis bilobafeed: these larvae are also known to be prey items ofA. alba. From observations of captive colonies ofAtta, we have demonstrated that pentastomid-egg contaminated faeces ofA. alba, introduced into the colony, are rapidly cut up and thrown onto the refuse dump, where, under natural circumstances they will be eaten byCoelosis. These larvae have an unusual and highly specialized gut physiology and parasite eggs will develop to an infective stage within the haemocoel in 70–96 days. Cockroaches are refractory to infection. Ants are the vital link in transmission since they literally deliver eggs to theCoelosislarvae. The strong trophic links which exist between the various components of the life-cycle offset a low fecundity of 100 eggs/female parasite/day but nonetheless maintain a high prevalence (86%) of infection.
Profilicollis botulus (Acanthocephala) abundance in the eider duck (Somateria mollissima) on the Ythan estuary, Aberdeenshire
Authors: Thompson A. B. 
Published: June 2009

SUMMARYThe abundance of Profilicollis botulus was monitored in eider ducks for 3 years. No significant difference in P. botulus abundance was found between eiders taken alive and those collected dead from the shore line, or between adult males and adult females. Adult male eiders had a seasonal pattern of infection. Incubating female eiders lost their infection in almost all cases, suggesting that a seasonal pattern of infection must also occur in these birds. Eiders in their first winter had P. botulus abundances which were approximately 10 times that of adult eiders, but by the following summer the abundance had declined to that found in adults. Data are compared with previous studies undertaken on the Ythan estuary. Captive eiders were used to determine the developmental rate of female P. botulus and the percentage of administered cystacanths which established in the intestine. There was no evidence to suggest that male and female P. botulus have different life–spans.
Differential cellular responses atHyalomma anatolicum anatolicumfeeding sites on susceptible and tick–resistant rabbits
Authors: Gill H. S. , Walker A. R. 
Published: June 2009

SUMMARYThe sequential, quantitative histological analysis of adultHyalomma anatolicum anatolicumfeeding sites on rabbits showed that the cellular reactions at tick feeding sites change in character and magnitude with time after attachment, and differ considerably from primary infestation to tertiary infestation. Neutrophils (62–68%) followed by mononuclear cells (22–24%) were the major component of the cellular infiltrate throughout primary infestation. Eosinophils accounted for 10% of the cellular infiltrate at 24 h after attachment. Their proportions declined thereafter, forming 9% of the infiltrate at 72 h and 5% at 144 h. Basophil infiltration in most of the feeding lesions was noticed by 24 h, but always in low numbers. Despite a slight increase in absolute numbers the proportion of basophils fell from 3% at 24 h to 2– at 144 h. In contrast to primary infestation the cellular reactions on tertiary infestations were characterized by a significant increase in the numbers of basophils and eosinophils and marked degranulation of mast cells and basophils as early as 24 h after attachment. As the feeding advanced there was an increase in the mean proportions of basophils from 4% to 9% and mononuclear cells from 22% to 38%, and a decrease in the proportion of eosinophils from 21% to 9%. However, neutrophils (42–53%) remained the major component of the cellular infiltrate. There was no significant difference in the nature and sequence of cellular events in the feeding sites of male and female ticks, although the lesions produced by feeding males were 5–10 fold smaller than those of females. Mast cells, basophils and eosinophils appeared to be the major host cells involved in the resistance response, manifested by protracted feeding, reduced engorgement weight and poor egg laying. The mechanisms by which these cells might interact to mediate resistance are suggested and discussed.
The population dynamics of Lepeophtheirus pectoralis (Müller): dispersion pattern
Authors: Boxshall G. A. 
Published: June 2009

The numerical relationships between a population of Lepeophtheirus pectoralis and its host population (plaice) have been described. There was no significant difference between infection levels in male and female plaice. In most of the monthly samples (75%) there was no significant relationship between host length and either the incidence or intensity of infection. The samples in which significant positive correlations occurred were usually taken within the period November to April. It is probable that the immigration of smaller fish, with lower levels of infection, from shallower water produces this effect.The parasite population was found to have an overdispersed distribution (variance > mean) within its habitat, the host population. The frequency distributions of numbers of parasites per fish were calculated and the negative binomial distribution was fitted to these. The fit was good in 22 of the 24 samples and the value of k, the exponent, was found to be directly related to the mean density of the parasite population. Iwao's (1970) method of dispersion analysis indicated that the observed negative binomial was generated by a model of randomly distributed clumps or colonies of individuals. A possible mechanism of producing this pattern was proposed based on evidence from studies of mortality in the parasite population (which indicated that all-or-none type mortality operates on the clumps at certain periods during the year), the infection process (which demonstrated that a single wave of infection produces an overdispersed spatial distribution) and the examination of parasites from individual fish (which displayed a clumping of parasites at certain stages rather than an even spread over the range of possible stages). The mechanism proposed is that the adaptations for host location of the infective copepodid stage tend to produce aggregations of these larvae in favourable areas of a heterogeneous habitat. Fish moving randomly into these areas will tend to be infected by more than one larva (a clump of larvae) at any one time when available for infection. The fish can be regarded as equivalent to random samples of the free larval population and the aggregated distribution of the parasite population on its hosts is therefore directly related to the aggregated distribution of the free-swimming infective larvae.
Population dynamics ofHymenolepis nanain mice: fecundity and the ‘crowding effect’
Authors: Ghazal A. M. , Avery R. A. 
Published: June 2009

Young white mice were infected with different doses of eggs or cysticercoids ofHymenolepis nanaand the subsequent faecal egg output was measured over a 3-day period. This was then correlated with worm numbers, determined after killing the hosts. The longest worm in each infection was measured and it was shown that crowding decreased the linear dimensions, number of eggs per proglottis and rate of proglottis production of these worms, but that their shape was not affected.The relation between total egg output and worm numbers was complex. In both egg-derived and cysticercoid-derived infections the egg production rose to a peak, fell and then levelled off to a constant rate with increasing worm numbers. Cysticercoid-derived worms were larger than egg-derived worms, but produced approximately the same number of eggs per unit of biomass. The differences in the egg output curves for the two types of infection were interpreted as being due to their size difference; this in turn may be a consequence of the host immunological response.
Studies on intrategumental pH and its regulation in adult male Schistosoma mansoni
Authors: Pax R. A. , Bennett J. L. 
Published: June 2009

SummaryThe intrategumental pH in adult male Schistosoma mansoni as measured with pH-sensitive microelectrodes is between 7.0 and 7.2, a value about one pH unit more alkaline than expected for equilibrium. This value is maintained for at least 4 h after isolation in media buffered with Hepes or CO2/ with or without serum present. CCCP (1 μM) and FCCP (10 μM) cause rapid acidification. DNP (1 mM) and Na-orthovanadate (1 mM) acidify but also cause significant depolarization of the tegument. NH (20 mM) depolarizes and acidifies the tegument with no evidence of transient alkalinization. High K+ (25 mM) accelerates the acidification. Removal of the NH+4 causes a large transient further acidification with recovery requiring as long as 40 min. High K+ (25 mM) delays the early stage of the recovery. Presence of CO2/HCO in the incubation medium does not accelerate the recovery rate nor does SITS (100 μM) inhibit the recovery. Intrategumental Na+ is elevated after an acid load and amiloride (3 mM) as well as low Na+ medium interfere with recovery from the acid load indicating that a Na+–H+ exchanger may be present in the tegumental membrane.
MetacyclicTrypanosoma vivaxpossess a surface coat
Authors: Gardiner P. R , Webster P , Jenni L , Moloo S. K 
Published: June 2009

SUMMARYCoated metacyclics ofTrypanosoma vivaxexist in the hypopharynges of infected tsetse flies and are extruded in low numbers when the flies are induced to probe onto warm slides or into medium. After extensive searching ofT. vivax-infected proboscides, and resort to a process for the examination of single, extruded, metacyclic trypanosomes, electron micro scopic evidence is presented that, contrary to an earlier report, metacyclicT. vivaxacquire a surface coat before contact with the mammalian host. SinceT. vivaxexhibits antigenic variation, the role of the surface coat in this species is likely to be functionally equivalent to the surface coat of the other tsetse-transmitted trypanosome species,T. bruceiandT. congolense.
Speciation and specificity of acanthocephalans. Genetic and morphological studies of Acanthocephaloides geneticus sp. nov. parasitizing Arnoglossus laterna (Bothidae) from the Mediterranean littoral (Sète-France)
Authors: Buron I. De , Renaud F. , Euzet L. 
Published: June 2009

SUMMARYAcanthocephaloides geneticus sp.nov. is described from Arnoglossus laterna (Bothidae) from the Mediterranean littoral (Sète-France). The new species most closely resembles Acanthocephaloides propinquus (Dujardin, 1845) Meyer, 1932, whose type host is Gobius niger (Gobiidae). A genetic comparison of the parasites collected from these two Teleostean fishes has confirmed the value of morphological differences which seemed too slight to raise the populations to species status.