bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro cloning of animal-infective bloodstream forms of Trypanosoma brucei
Authors: Hirumi H. , Hirumi K. , Doyle J. J. , Cross G. A. M. 
Published: June 2009

SummaryClones of animal-infective bloodstream forms of Trypanosoma brucei (stocks S.427 and LUMP 227) were made by transferring a single organism from bloodstream-form cultures into each well of Microtest II Tissue Culture Plates containing bovine fibroblast-like feeder cells. When the number of trypanosomes increased to 102–103/well on days 4–16, they were transferred into plastic T-25 culture flasks also containing feeder cells and fresh medium. Cultures were thereafter maintained by partially replacing the trypanosome suspension with the same volume of fresh medium (diluting the density to 2–5 × 105 trypanosomes/ml) every 24 h. Sub-cultivations could be made by transferring 1–2 ml of the trypanosome suspension to a new culture flask at 4–5 day intervals. A total of 42 clones in the 3 series TC221, TC52 and TC227, carrying variable antigen types (VATs) 221, 052 and ILTat 1·4, respectively, have been established. Average population doubling times for clones of TC221, TC52 and TC227 were 8·7, 14·5 and 15·5 h respectively. Of 35 populations examined, 34 clones retained the original specificity of their VATs for at least 8–32 days from cloning. One cloned population of TC52 consisted of 99·8% VAT 052 and 0·2% VAT 221 at the time when the first VAT test was made on day 18.
Passive protection of mice against infection withTrypanosoma cruziwith plasma: the use of blood- and vector bug-derived trypomastigote challenge
Authors: McHardy N. 
Published: June 2009

SummaryA study was made of the protective effects of plasma (CMP) from mice convalescent from infection withTrypanosoma cruzi. A single dose of CMP was injected into mice infected with blood trypomastigotes of 1 of each of 5 strains ofT. cruzi. Protection was greatest with strains BG, M1 and Y, and least with strain Peru. Strain Tulahuen was of intermediate susceptibility. The protective effect of CMP was found to be similar in mice infected by metacyclic trypomastigotes harvested from vector bugs and mice infected by blood trypomastigotes. Plasma (IMP) from mice hyperimmunized with 6 doses of a killedT. cruziepimastigote vaccine with saponin as an adjuvant gave no protection against challenge with strain Y, although a group of mice hyperimmunized in parallel with those from which IMP was taken were strongly resistant to challenge.
Studies of antigens inPlasmodium yoelii
Authors: Panton Lindsey J. , Knowles G. , Walliker D. 
Published: June 2009

SummaryThe inheritance of an antigen designated Py-1 in the rodent malaria parasitePlasmodium yoeliihas been investigated. A cross was made between 2 lines differing in the electrophoretic mobility and quantity of Py-1 detected by crossed immunoelectrophoresis. In 10 clones isolated from the progeny of the cross the level of Py-1 always correlated with the virulence of the infection and it was concluded that these characters were different phenotypic effects of the same gene mutation. The electrophoretic mobility of Py-1 segregated independently of the virulence character and was therefore controlled by a different gene. These two antigenic markers also recombined with isoenzyme and drug-sensitivity characters distinguishing the parent lines.
Tenebrio molitor(Coleoptera): effect of metacestodes ofHymenolepis diminuta(Cestoda) on haemolymph amino acids
Authors: Hurd Hilary , Arme C. 
Published: June 2009

SummaryHaemolymph free amino acids (HFAAs) in adultTenebrio molitorvaried in concentration with beetle age. Between 9 and 30 days post-emergence the concentration range was 34–94 mMwith a peak occurring in 15-day-old insects. Much of this age-related variation was due to changes in the concentration of a single amino acid, proline. An analysis of concentrations of individual HFAAs in 15-day-old beetles, following infection with metacestodes ofHymenolepis diminuta, revealed that changes in female insects are more marked than those occurring in males. In the former, changes occurred in the concentration of 9 amino acids (isoleucine, leucine, arginine, serine, threonine, tyrosine, phenylalanine, proline and alanine/citrulline) whereas in the latter only 4 amino acids were affected (threonine, glycine, histidine and arginine). It is suggested thatH. diminutamay interact with the endocrine system of its beetle host.
Pathophysiology ofHymenolepis diminutainfections inTenebrio molitor:effect of parasitism on haemolymph proteins
Authors: Hurd Hilary , Arme C. 
Published: June 2009

SummaryThe effects of metacestodes ofHymenolepis diminutaon haemolymph proteins ofTenebrio molitorare restricted to female hosts. In beetles aged 15 days post-emergence, and harbouring 12-day-old metacestodes, haemolymph concentration is 46·7% higher than in non-infected animals and similar effects are found in longer standing infections. Electrophoresis of haemolymph revealed the presence of 13 bands. Densitometric analysis showed that only band 2/3 was significantly elevated in infected hosts although band 7/8 also showed an increase. These bands were also present in egg homogenates and are thought to be vitellogenins. It is therefore proposed that the excess protein found in infected beetles is a female-specific protein resulting from an interaction between the parasite and the host endocrine system.
Trichuris muris: structure and formation of the egg-shell
Authors: Preston C. M. , Jenkins T. 
Published: June 2009

SummaryThe development of the egg-shell of the trichuroid nematode, Trichuris muris, was observed by light and electron microscopy. Initial stages of shell formation occurred immediately following sperm entry into the oocyte in the spermatheca of the female worm. The external vitelline layer separated from the oolemma, reticulate oocyte granules were discharged into the resultant perivitelline space and stored glycogen contributed to the formation of the chitinous shell. A lipid layer developed between the inner surface of the chitinous layer and the oolemma. The fully formed egg-shell thus comprised an external vitelline layer, a middle chitinous layer and an inner lipid layer. The outer vitelline layer resembled a unit membrane with strands of particulate material attached to its outer surface. The middle chitinous layer was composed of chitin microfibrils encased in a protein coat; the sheets of microfibrils were arranged as parallel lamellae forming a helicoidal architecture. The inner lipid layer contained a variable number of loosely arranged strands of electron-opaque and less-opaque material.
Parasite density and the fecundity of Angiostrongylus cantonensis in rats
Authors: Kino Hideto 
Published: June 2009

SummaryThe larval output of Angiostrongylus cantonensis at different initial densities in rats was examined throughout the reproductive life-span of the worms using a modified dilution technique. With an initial density of 2 worms the mean duration of larval output was 414·2 days. The output was at a level above 50000 larvae/female/day from 15 to 45 weeks after infection. The mean total output was 18·9×106 larvae/female. The larval output/female decreased with an increase in the worm burden and also with the passage of time after infection. The longevity of host rats also decreased with increasing worm density and many of the heavily infected rats died early during infection. These results suggest that worm density has an effect on the fecundity of this parasite, and that the effects may be due to fibrous changes in host lung tissue but not changes in the physiology of the worms. It is also suggested that density-dependent effects on fecundity play a role in the population dynamics of both the parasite and host as regulatory mechanisms in the field.
Taenia ovis recombinant vaccine – ‘quo vadit’
Authors: Rickard M. D. , Harrison G. B. L. , Heath D. D. , Lightowlers M. W. 
Published: June 2009

SummarySeveral years have elapsed since the publication by Johnson et al. (1989) of the cloning of a recombinant antigen from the cestode parasite Taenia ovis which stimulated high levels of protective immunity in sheep. A great deal of subsequent research and development was necessary to bring the fledgling vaccine to the point of being a registered commercial product. The results of these subsequent studies are dealt with briefly in this paper, including the results of field trials. The T. ovis vaccine was registered by the New Zealand Animal Remedies Board in February 1994. Where then is the commercial product ? This paper gives a background to market problems which have emerged through the politics (and realities) of the NZ T. ovis control campaign. It serves as notice that the best science dedicated to producing vaccines or products for parasitic, or other, diseases often faces significant hurdles in the real world of commerce and politics.
The development of oral vaccines against parasitic diseases utilizing live attenuatedSalmonella
Authors: Chatfield S. N. , Roberts M. , Dougan G. , Hormaeche C. , Khan C. M. A. 
Published: June 2009

SummaryGenetically defined, live attenuatedSalmonellavaccines are proving useful both as oral vaccines against salmonellosis and for the development of multivalent vaccines based on the expression of heterologous antigens in such strains. Several candidate attenuatedS. typhistrains are at present being evaluated as new single dose oral typhoid vaccines in human volunteers. The emergence of such a vaccine will facilitate the development of multivalent vaccines for humans. Many antigens from different infectious organisms have been expressed in attenuatedSalmonella. A focus of this work has been on developing vaccines against parasitic diseases. This review will summarize the efforts that have been made in this area.
The structure and life history ofCrithidia pulicis, n. sp., parasitic in the alimentary tract of the human flea,pulex irritans
Authors: Porter Annie 
Published: June 2009

1.Crithidia pulicis, n. sp., is a parasite of the alimentary tract of the human flea,Pulex irritans.2. The fleas used in this investigation were bred to the third generation in special “flea cages” on the human body. “Wild” fleas were examined and yielded the same parasite. Both larvae and adult fleas were examined.3.C. pulicisexhibits pre-flagellate, flagellate and post-flagellate stages in its life history and these phases gradually develop, the one from the other.4. The flagellate form is very active, movement being accomplished by means of the myonemes of the membrane and body.5. Pre-flagellates (figs. 1−8) are oval bodies, from 2·3 μ to 7 μ long by 1·5 μ to 4·5 μ broad. The nucleus contains much chromatin and a small karyosome may be present. The blepharoplast is large. The flagellum develops from a chromatophile area. The rate of acquisition of flagellum and membrane varies in individual parasites. Division rosettes are frequent. The pre-flagellates have a somewhat frail appearance.6. The flagellates ofC. pulicis(figs. 9−17) are 26 μ to 65 μ long. Their cytoplasm is richly but finely granular, the nucleus well marked, the blepharoplast large, showing slight variations in shape. Chromidia may be present. The undulating membrane is large, well marked and possesses myonemes which can be detected in the living organism. The free flagellum is relatively short.7. Post-flagellates (figs. 23−36) are from 3 μ to 6 μ. by 2·0 μ to 4·6 μ. They occur in the rectum and dejecta of the fleas. They are produced by concentration of the protoplasm round the nucleus and blepharoplast with absorption of the membrane and flagellum and finally the production of a thin varnish-like coat.8. Longitudinal division (figs. 15−22) is the method of multiplication. It occurs in the pre-flagellate and flagellate stages. It may be symmetrical or asymmetric. Division is initiated by that of the blepharoplast, followed by that of the flagellum, membrane and nucleus and finally the body cytoplasm. Two types of asymmetric division have been observed.9. The method of infection is contaminative, the post-flagellates in the faeces being the source of infection. There is no evidence of hereditary infection.10.Crithidia pulicisis a member of the genusCrithidia, and is a true parasite of the insect,Pulex irritans.
A Revision of the Coccidia Parasitic in Man
Authors: Dobell Clifford 
Published: June 2009

From a study of the organisms themselves, so far as this has been possible, and from an analysis of all accessible records relating to them, I conclude that there are four distinct species of coccidia which may parasitize man. These are: (1) Isospora hominis Rivolta, 1878 (emend.), discovered by Kjellberg in 1860. and recently investigated by Wenyon; (2) Eimeria wenyoni n.sp., a form discovered in 1915 by Wenyon; (3) Eimeria oxyspora n.sp., another new form, here described for the first time; (4) an undetermined species of Eimeria (?) which was discovered by Gubler in 1858. This last inhabits the human liver, whilst the three others probably live in the small intestine. Probably some seventy cases of infection with the Isospora have now been seen, mostly in persons who have been in the Near East; but the other parasites appear to be extremely rare, and little is known concerning their probable geographical distribution.All these parasites are probably peculiar to man. There is no evidence that any of them is or can be parasitic in any other host. The prevailing belief that the coccidia of man are identical with those of rabbits, cats, or dogs, is therefore unfounded. Furthermore, there is as yet no good evidence to show that man may harbour any species of coccidia other than the four just enumerated. All these forms, however, require fuller investigation. They are here briefly and incompletely described from the data at present available.There is at present no proof that the coccidia of man—with the probable exception of the species occurring in the liver—can produce a clinically recognizable pathological condition of “coccidiosis”: and as yet no method of treatment which will eradicate an infection with any species has been discovered.
On the Cultivation ofEntamoeba histolyticaand some other Entozoic Amoebae
Authors: Dobell Clifford , Laidlaw P. P. 
Published: June 2009

The method devised by Boeck and Drbohlav for the cultivation ofE. histolyticahas been successfully used for cultivating this species and various other entozoic amoebae of man and monkeys.Various modifications of the original technique have been tried, and several improvements are here described. Among these are methods of cultivation (involving the addition of solid rice-starch to the medium) whereby (1) more luxuriant and prolonged growth of the amoebae, and (2) all stages—including encystation and excystation—in the life-cycle ofE. histolyticaand other species can be obtainedin vitro.Methods by which cultures of entozoic amoebae can be initiated from encysted forms have been discovered and are also described, and some indications are given for the isolation of pure strains from mixed cultures.The influence of the accompanying bacterial flora upon the various amoebae cultivated has been studied, and is briefly discussed in the light of certain experimental findings.Loss of infectivity to kittens has been observed inE. histolyticaas an apparent result of cultivation in media containing solid starch.
Notes on the Genus Leucochloridium Carus (Trematoda)
Authors: McIntosh Allen 
Published: June 2009

Adult trematodes belonging to the genus LeucocMoridium Carus are here reported for the first time from North America. These flukes are intestinal parasites of birds and proved to be previously undescribed species.In the present paper a key separating the species of the genus is given, and the following are described and figured as new species:Leucochloridium certhiae n. sp. from Certhia familiaris americana;Leucochloridium mniotiltae n. sp. from Mniotilta varia;Leucochloridium icteri n. sp. from Icterus galbula;Leucochloridium vireonis n. sp. from Vireo griseus griseus;Leucochloridium sorae n. sp. from Porzana Carolina.
Observations on the Influence of Salt and other Agents in modifying the Larval Development of the Hookworms: Ankylostoma duodenale and Necator americanus
Authors: Nicoll William 
Published: June 2009

1. There can be no doubt that Ankylostomiasis has obtained a very firm hold in the coastal districts of North Queensland, and every effort should be made to arrest its spread, and if possible eradicate it.2. Experience in other parts of the world, notably the United States and Germany, has demonstrated the great difficulty of coping with the disease, even with the most energetic of preventive measures.3. The disease gives rise to much sickness and inefficiency especially amongst children, and although competent medical treatment is usually efficacious the most satisfactory and permanent results are to be expected in the direction of prevention.4. The chief preventive measures are individual cleanliness and thorough and rapid destruction of night soil and deposits of faecal material.5. In the presence of a properly organised sanitary system, intelligently utilised, there should be little or no risk of infection. It is the promiscuous distribution of excreta that is the chief source of the spread of infection.6. If the indiscriminate deposit of faecal material be not prevented, the matter resolves itself into a problem of considerable difficulty.7. The more commonly used disinfectants, if thoroughly employed, would render the faecal material comparatively innocuous, but their use is not less laborious than the proper removal of the faecal material and its disposal in properly constructed receptacles.8. Common table salt has a decidedly injurious effect upon the hook-worm eggs but it requires to be brought into very intimate contact with the infected material. The process of merely sprinkling the surface is almost futile unless the salt be used in enormous quantities.9. When mixed with faecal matter, sand promotes the development of hook-worm larvae, but when used as a covering of a certain depth it arrests development.10. Exposure to direct sunlight of sufficient intensity kills hook worm eggs and larvae very rapidly.
On the Life-history of Melittobia acasta, Walker; a Chalcid Parasite of Bees and Wasps
Authors: Browne Frank Balfour 
Published: June 2009

Melittobia is a chalcid, ectoparasitic upon a number of species of Hymenoptera and upon the pupae of certain flies. The insect was bred in the laboratory and the life-history is described in detail.A number of experiments were made with regard to possible hosts and as to feeding and reproduction and certain points are of some interest.For instance, the male apparently does not feed but the female uses her ovipositor with which she punctures the eggs, larvae or pupae of various insects, afterwards sucking the blood which oozes from the puncture. Such eggs, larvae or pupae, in spite of repeated punctures, may continue to develop.Before beginning oviposition upon the surface of a suitable host, the female punctures the host one or more times with her ovipositor and apparently injects an anaesthetizing fluid, since insect larvae and pupae, upon which eggs have been laid, very rarely develop farther and yet remain fresh for a considerable time extending to many months.With regard to reproduction, inbreeding appears to be normal, mating usually taking place between two individuals of the same brood and later between the female and one of her own offspring. Virgin females, unable to find a male, lay a few eggs, which always produce males, the first of which to emerge mates with the female.The female is very prolific and may lay as many as twelve hundred eggs in two or three batches, mating taking place before each batch is laid. The last eggs of a batch are almost invariably male eggs, indicating that the female has exhausted her supply of spermatozoa.A virgin female, whose eggs are removed so that she cannot rear a mate, may lay as many as ninety eggs during her life-time, her length of life being more than doubled, and such a female will survive through the winter, even withstanding frost, whereas fertilized females apparently all die in October or November at the latest.All the eggs of a virgin female are apparently capable of developing and all such eggs produce males.
Studies on the growth ofPediculus(Anoplura)
Authors: Buxton P. A. 
Published: June 2009

1. The paper discusses the points of difference between the three larval instars inPediculusand the changes in proportion which take place during growth, not only during larval life but also at the final moult.2. It is easy to separate larvae of the first instar from others, more difficult to distinguish those in the second and third instars. The principal points of difference are as follows:First instar. Setae on dorsum of abdomen, few, long and in longitudinal lines: one median pair on most segments. Paratergal plates (carrying spiracle) absent. Mean measurements as in Table I, the best point of distinction between instars being in length of third tibia, which is 0·197 mm. in first instar. Ratio of head to thorax and abdomen about 1:2·8Second instar. Setae of dorsum of abdomen in one transverse row, containing 2–3 pairs of setae. Paratergal plates present (as also in third instar). Mean length of third tibia, 0·270 mm. Ratio of head to thorax and abdomen about 1: 3·5.Third instar. Setae on dorsum of abdomen, not in one row, but somewhat irregular: a pair of minute supplementary setae, on seventh and eighth segments, close to midline. Mean length of third tibia, 0·363 mm. Ratio of head to thorax and abdomen about 1:4·3.3. During larval life the dimensions of all parts increased as geometrical progressions (Dyar's law), but the rate of increase is different in different parts of the body, so that the proportions, for instance, of head to thorax and abdomen alter with growth; in other words, growth is allometric or heterogonic. But when the insect attains maturity the measurements of several of the parts depart significantly from the geometrical progression which has prevailed during larval life. In most parts of the body the increase at maturity is greater in females than males (no point of distinction having been observed in larvae in the preceding instars); but in the length of the third tibia the increase in the female is much less than in the male. Among other insects in which metamorphosis is slight there are several in which the rate of growth of parts alters at the last moult and becomes different in the two sexes; in some indeed the difference develops much earlier than the last moult. Probably, therefore, it would be true to say that regular allometric growth is generally disturbed by the development of secondary sexual characters.It is a pleasure to acknowledge help received from Dr J. S. Huxley.