bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observations on the bionomics of the free-living stages of Trichostrongylus vitrinus
Authors: Rose J. H. , Small A. J. 
Published: June 2009

AbstractEggs of Trichostrongylus vitrinus in faecal pellets deposited on grass plots each month from April 1981 to March 1982 developed into infective larvae. From October to March development was slow and mortality of the pre-infective stages was very high. From April to September development was more rapid. The weather was generally dry and mortality of the pre-infective stages was high on plots with short herbage but was lower on most of the plots with long herbage, especially in July and August. In the laboratory, development of eggs into infective larvae was completed at temperatures ranging from 4°C to 27°C in faecal pellets which were either kept moist or dried out slowly, but not in faecal pellets which dried out rapidly. The rate of development increased as the temperature rose. Infective larvae survived for up to 16 months on the herbage of grass plots; some survived during very cold weather in the winter of 1981/82. In the laboratory, infective larvae suspended in tap water survived even longer at 4°C and 10°C but not at higher temperatures. They were rapidly killed by continuous freezing. They Survived for up to 8 weeks when subjected to desiccation, The relationship between climatic conditions and the development and survival of the free-living stages is discussed
Scanning electron microscope studies of the small intestine of rats maintained on a low protein diet and infected with Nippostrongylus brasiliensis
Authors: Martin Jean 
Published: June 2009

SummaryIn undernourished rats infected with Nippostrongylus brasiliensis partial villus atrophy was observed in large areas of the anterior and posterior regions of the intestine. In addition, the following changes in structure were observed; some areas of the intestine contained misshapen villi which lacked microvilli on the lateral surfaces; cell-like bodies devoid of microvilli appeared to be budded off from the sides and tips of some malformed villi and there appeared to be extensive leakage of blood constituents into the lumen of the intestine. Morphological changes were present up to day 24 of the infection when the experiment was terminated. The possible consequences of the extensive breakdown of villus structure are discussed.
A new method for the partial purification of leishmania amastigotes from cutaneous lesions
Authors: Infante R. B. , Hernandez A. G. , Riggione F. , Dawidowicz K. 
Published: June 2009

SummaryAmastigotes from Leishmania braziliensis and L. mexicana were isolated from cutaneous lesions in infected animals using the plant lectin Concanavalin A as a specific agglutination agent. Amastigotes were collected in preparations of up to 95% purity as determined by cell count. The parasites obtained by this method showed no apparent loss of viability as measured by growth rates and DNA replication, or pathogenicity as measured by routine passages in hamsters or mice.
Presence of Trypanosoma cruzi antigen on the surface of both infected and uninfected cells in tissue culture
Authors: Abrahamsohn I. A. , Kloetzel J. K. 
Published: June 2009

SummaryLLC-MK2 cell monolayers infected with Trypanosoma cruzi were shown by immunofluorescence to present parasite antigens on the surface of both parasitized and non-parasitized cells after completion of the first intracellular cycle and rupture of infected cells. The cell-culture supernatant fluid at this stage, as well as the supernatant fluid of parasites left overnight in culture medium were concentrated and contained antigen capable of binding to uninfected cell monolayers. The origin of this antigen, as well as its eventual role in the pathogenesis of Chagas' disease, are discussed.
Enzyme variation in Trypanosoma brucei spp. I. Evidence for the sub-speciation of Trypanosoma brucei gambiense
Authors: Tait A. , Babiker Eldirdiri A. , Le Ray D. 
Published: June 2009

SummaryThree groups of stocks of Trypanosoma brucei ssp, defined by the criteria of host, human serum resistance and place of isolation as T. b. gambiense, T. b. brucei (Nigeria) and T. b. brucei/rhodesiense (non-gambiense, Uganda) were screened for electrophoretic variation at 20 enzyme loci. One enzyme (Peptidase C) was found to differentiate all T. b. gambiense stocks from the other T. brucei stocks and, taken together with specific variants of 5 other enzymes, could be used to unambiguously define T. b. gambiense stocks. Using a population genetics approach, the frequencies of the different variants in the three groups of stocks were estimated and from them the average similarity and difference between groups were measured using the statistics of genetic identity (I) and genetic distance (D). These results show firstly, that T. b. gambiense is more different from the other two groups than they are from each other and, secondly, that the values of I and D obtained are consistent with T. b. gambiense constituting a sub- or sibling species of T. brucei. Three domestic animal isolates from Zaire and Cameroun were also screened for enzyme variation and two of these identified as T. b. gambiense, thereby establishing the existence of an animal reservoir host. In parallel, these stocks were tested for human serum resistance resulting in the same identification. Studies of the antigen repertoires and antigen gene structure were carried out by other workers on all the T. b. gambiense stocks reported here and the same conclusions reached as to the identification and ability to discriminate this subspecies from other groups of T. brucei stocks. The results presented here are discussed in relation to other published data on enzyme variation in T. brucei.
Description of a Herpetomonas parasitic in the alimentary tract of the common green-bottle fly, Lucilia sp
Authors: Strickland C. 
Published: June 2009

1. The parasite described inhabits the alimentary tract of two species of Lucilia. In addition it has a resting stage—the ‘cyst’—which is passed in the voided excrement of the insect.2. When the cyst is ingested by a fly it grows in length and becomes flagellated in the ‘crop’; in the midgut it greatly elongates and multiplies rapidly by division; in the hindgut it first shortens, then becomes spherical, and finally oval and cyst-like, meanwhile losing its flagellum.3. The cysts measure 3 μ, the fully flagellate forms 20 μ, in length.4. The cysts possess a cytostome and cytopharynx, the functions of which are probably nutritive.5. The flagellum consists of two parts (i) a cytoplasmic part, which probably subserves the power of movement and which I therefore propose to call the kinetoplasm, and (ii) a thread of chromatin secreted by the rhizoplast.6. The function of the chromatin in the flagellum is probably to sustain a filamentous form.7. The nucleus divides by a definite process something akin to mitosis.8. The chromidia serve as reserve material for the supply of chromatin in the cell. They are secreted probably by cell-plastids.9. I propose the name of this parasite be Herpetomonas luciliae, and that the genus Herpetomonas should be defined so as to include the forms described as Leptomonas.
Further Observations on the Life-history of Limnaea truncatula
Authors: Walton C. L. , Jones W. Norman 
Published: June 2009

1. Egg masses of Limnaea truncatula collected in March 1925 were isolated and hatched in the Laboratory. The average number of ova per mass (for 20) proved to be 9·75.2. The hatching period lasted 12 to 26 days, with an average of 20–21 days (for the Spring generation).3. On hatching, young snails were isolated, reared, and again oviposited during the first week of July. Ova from these snails again hatched during the first week of August.4. It is thus shown that L. truncatula is self fertile; that oviposition can commence at a shell altitude of 4 to 4·5 mm.5. Further data on growth-rates were obtained, showing that two (and probably three) generations occur between March and October.
The Control of Tick Infestation and a Related Disease of Lambs in North Wales
Authors: Walton C. L. 
Published: June 2009

(1) An account is given of a serious infestation in sheep and lambs by Ixodes ricinus in the uplands of Denbighshire, North Wales.(2) This infestation was accompanied by serious disturbance of health resulting in the general deterioration of the flock and the death of lambs.(3) Experimental dippings were commenced in 1924, using a special “short-interval” arsenical dip supplied by the Cooper Technical Bureau, London. Serial dippings were made each spring at five-day intervals. When possible an early autumn series was conducted.(4) The objects were (a) to control the infestation, (b) to control the diseased condition, and (c) to attempt to eradicate ticks from the land.(5) The control of both the ticks and the disease were easily effected. A few sporadic cases of disease did occur during the course of the experiment.(6) Eradication has not yet been accomplished, but the average number of ticks was reduced from 121 per animal in May 1924 to 0-96 per animal in July 1926.(7) It is therefore suggested that short-interval dipping for serious tick infestation in sheep is practicable on British hill farms, and that resultant mortality from disease can thereby be reduced.
Some observations on the Biology and Structure of Ornithodorus savignyi, Andouin
Authors: Cunliffe Norman 
Published: June 2009

1. The biology, as studied under laboratory conditions, of O. savignyi is very similar to that of O. moubata.2. Females may oviposit over 400 eggs, of which at least 60 per cent, may be fertile; parthenogenesis does not occur.3. An increase in temperature of 8° C. (from 22° C.) decreases the longevity of the female from 775 to 358 days, i.e. by 45 per cent.; an increase of 7° C. (from 30° C.) reduces the period required for the production of third stage nymphs by 26 per cent. At 30° C., the mean minimum periods required for metamorphosis are 60 days for males and 73 days for females (cf. O. moubata, 36 days for males and 45 days for females). Reproduction was inhibited at 37° C.4. Moisture is an unfavourable factor, decreasing the vitality of the individual at each stage of growth.5. Changes in external anatomy undergone during development are similar to those already described for O. moubata.
The Life History ofNematodirus filicollisRud., a Nematode Parasite of the Sheep's Intestine
Authors: Boulenger Charles L. 
Published: June 2009

1. The eggs ofNematodirus filicolliswhen laid contain an embryo with seven or eight cells, they pass out of the infested host with the faeces.2. Even under favourable conditions development takes place slowly and the embryos are not ready to hatch until 24–28 days have elapsed. In their early stages the embryos are not able to withstand desiccation and are killed if frozen or subjected to high temperatures.3. Whilst still within the egg-shell the embryo undergoes two ecdyses and when ready to hatch is enclosed in a tightly fitting sheath formed by the incompletely cast skin of the second moult; the larvae on liberation from the egg-shell are therefore in a more advanced condition than those of most other Strongylids (e.g.HaemonchusorAnchylostoma) and are in a stage comparable with that reached by the latter at the end of their period of free existence.4. The sheathed larvae are often retained for a long time within the egg-shells and both in this position and after hatching can resist complete desiccation for considerable periods (twenty months or even longer); when dried they are able to withstand freezing as well as temperatures much above those likely to be met with in the open.5. The free larvae will live for a considerable time in water, they possess well-developed migratory instincts and climb vertical surfaces, such as grass stems and blades, and the glass walls of the vessels in which they are kept.6. The sheaths are cast off by the larvae when these are subjected to temperatures approximating to the blood-temperature of the host; completion of the second moult occasionally also takes place at laboratory temperatures under certain abnormal conditions.7. No infection experiments were made on sheep, but other evidence shows that these animals must become infected by swallowing the sheathed larvae, either when free or whilst still enclosed in the eggshells.8. A number of young stages of the parasite were met with in the intestines of sheep, the smallest of these being only little more advanced in structure than the larvae just after ecdysis.
Progenesis of Phyllodistomum lesteri sp.nov. (Trematoda: Gorgoderidae) in freshwater shrimps
Authors: Wu Kuang 
Published: June 2009

1. A progenetic metacercaria of Phyllodistomum lesteri sp.nov. is found encysted in the fresh-water shrimps, Palaemon asperulus von Marten and P. nipponensis de Haan.2. A systematic description is made of this new species including general characteristics of the family, subfamily and genus and a list of the existing 29 phyllodistomes.3. In general, the new form resembles Pleurogenes medians with regard to its progenetic development.4. Feeding experiments suggest that two species of fish, Odontobutis obscura and Pelteobagrus fulvidraco, and a species of toad, Bufo bufo asiaticus, are not the final hosts of Phyllodistomum lesteri sp.nov.
“Red-Cell Adhesion” in Trypanosomiasis of Man and Animals
Authors: Duke H. Lyndhurst , Wallace J. M. 
Published: June 2009

The more important points that have emerged in the course of our investigations may now be assembled.(1) An adhesion phenomenon has been described in which, in certain circumstances, red blood corpuscles adhere to trypanosomes.(2) We believe this red-cell adhesion to be a manifestation of the adhesion phenomenon already described by other workers both with trypanosomes and spirochaetes.(3) The substance responsible for this phenomenon of adhesion is designated in this paper adhesin.(4) The red-cell adhesion test has been studied in relation to several strains of polymorphic trypanosomes, all of which were either recently isolated from naturally infected man or animals, or had been recently passed cyclically through tsetse.(5) It is shown that the adhesion phenomenon is irregular and uncertain in its appearance. A single or even a number of negative observations do not exclude trypanosomiasis. A positive reaction, on the other hand, indicates recent or actual infection with a trypanosome of the same group, but not necessarily specifically identical with that employed as antigen in the test. Thus T. gambiense adhesin bloods not uncommonly react with T. rhodesiense trypanosomes and also on occasion with the Damba strain: the converse is apparently of less common occurrence.(6) Adhesins appear in an animal's blood in the course of its infection with trypanosomes, whether the animal be treated with trypanocidal drugs or not. When sterilising doses of such drugs are employed the adhesins gradually disappear in the course of a few months; but in untreated infections of T. gambiense they have been shown to persist in an active form for more than two years.(7) With our material it was found impossible to distinguish between “passage” and “relapse” strains by means of the adhesion test. On the contrary it was found, at all events with T. gambiense, that the best way to call forth the reaction in the blood of animals long infected is to employ trypanosomes from a very early infection.(8) Guinea-pigs have been found to be unsatisfactory animals in which to demonstrate adhesins; they are, however, useful as a source of sensitive trypanosomes. When only guinea-pig elements are present in a test a positive reaction is indicated by platelet not by red-cell adhesion.(9) The presence of adhesins in the blood has no apparent relation to immunity against the homologous trypanosome.(10) The test has been applied to over 200 human cases of trypanosomiasis in the Uganda Protectorate, and with six of these repeated observations were made. Some of these human cases reacted both to T. gambiense and T. rhodesiense, but none to T. rhodesiense alone.(11) A partial analysis has been made of the mechanism of red-cell adhesion, which has been shown to be in some way associated with the presence of the red corpuscles of primates. This fact probably explains why other workers appear not to have noticed red-cell adhesion in the extreme form we have described in this paper.
Studies on the anthelmintic activity of hexylresorcinol and tetrachlorethylene
Authors: Rogers W. P. 
Published: June 2009

1. A method for examining conditions governing anthelmintic activity in the small intestine is described. Nippostrongylus muris in the rat was the test organism and hexylresorcinol and C2C14 were the drugs examined.2. The efficiency of hexylresorcinol was reduced by 50% in 1% sodium tauroglycocholate which reached a concentration of 1·3% in the rat small intestine. The adsorption of this drug on mucin reduced its concentration in intestinal fluids and prevented penetration to parasites under mucus. These inhibiting factors account for the inactivity of hexylresorcinol in the rat.3. Tetrachlorethylene, which stimulated N. muris to leave mucus and enter fluids in the intestinal lumen, was not inhibited by bile salt and was found to act rapidly in the rat.4. Sodium laurate activated hexylresorcinol more efficiently than sodium oleate at pH. 6·5. Both soaps showed intrinsic anthelmintic properties.5. The results obtained in examining the rate of movement of fluids down the intestine and the effects of detergents, bile salts, mucin and ascorbic acid on drug activity are discussed.
The effects of acids on a soil nematode
Authors: Stephenson William 
Published: June 2009

1. The effects of the following acids were studied: hydrochloric, nitric, sulphuric, formic, acetic, propionic, butyric, isovaleric, glycollic, lactic, oxalic, malonic, succinic, malic, tartaric, and citric.2. The general effects of immersion in acid media include an increased stickiness of the cuticle in certain solutions, and the development of lateral bulges in the cuticle at the anterior region of the body, not necessarily in the same solutions. Movement gradually decreases, and death eventually occurs, often followed by swelling.3. The survival times in various solutions were noted. Preliminary experiments showed that the logarithm of the survival time was approximately proportional to the logarithm of the normality of the acid. Later results showed great variability, and it was necessary to restrict the work to a single normality of each acid.4. The toxicities of 0·206 N solutions of the sixteen acids were measured. These results showed that the mineral acids had markedly greater effects than the organic acids, and the importance of the former was further illustrated by using mixtures of HCl containing varying amounts of organic acids. The differences between the mineral acids may be explained by the lyotropic effects of the anions.5. Equal normalities of organic acids were made up in a solution of HCl sufficiently strong to render the organic acids almost entirely undissociated. The relative toxicities of the mixtures were essentially the same as those of the dissociated acids.6. The differences between the acids are thus partly due to the pH differences, and partly due to the dissimilar effects of the undissociated acids. The latter are believed to be due to a variety of causes, including molecular size, polarity of the molecule, and other factors as yet undecided.
Turning sickness of cattle and Trypanosoma theileri
Authors: Carmichael J. 
Published: June 2009

The disease known as Turning Sickness was first recorded by Mettam (1934) in this journal and later more fully described by Mettam & Carmichael (1936).The condition has been defined as a protozoan encephalitis of cattle and one of the most striking features of the disease is the demonstration of schizonts indistinguishable from those of East Coast fever in the cerebral lesions of affected animals.
Chloride regulation and the function of the coxal glands in ticks
Authors: Lees A. D. 
Published: June 2009

Chloride regulation. Following the ingestion of a blood meal the tick excretes about half the ingested water in the coxal fluid. The mean haemolymph chloride concentration before feeding is 1.00% and after feeding 0.96% NaCl; and that of the coxal fluid, 0.80% NaCl. These results confirm the values given by Boné (1943).Morphology of the coxal glands. These comprise the coxal glands proper, which elaborate the bulk of the coxal fluid, and the smaller accessory glands of unknown function. Each flask-shaped coxal gland consists of two distinct regions, an outer ‘filtration chamber’ and an inner system of tubules. The latter lead to the external opening. The filtration chamber, which communicates with the tubules at only one point, is highly folded into an elaborate series of pockets and fingers which closely invest the tubules; numerous small muscle fibres inserted in these pockets pass outwards from the gland to attachments on the body wall. The histology of the two regions is entirely different: the filtration membrane is only 1–2μ in thickness and its cellular origin is much obscured: the tubule walls are 5–30 μ in thickness, are composed of cells with a dense, deeply staining cytoplasm, and are richly supplied with tracheae. In Ornithodorus delanoei acinus the walls of the sac-like coxal glands are lined both by ‘filtration membrane’ and by large irregular groups of ‘secretory’ cells; there are no true tubules.Function of the coxal glands. The production of coxal fluid is under muscular control. It is believed that the contraction of the coxal gland muscles enlarges the filtration chamber and sets up a sufficient pressure difference across the membrane to initiate filtration into the gland. In the subsequent passage of the fluid down the tubules threshold substances such as chloride are reabsorbed. That the coxal fluid is primarily an ultrafiltrate of the haemolymph is suggested by (a) the rapid passage of dyes and even haemoglobin into the coxal fluid after injection into the haemolymph and (b) the very high rate of liberation of fluid. Serum albumen sometimes passes into the coxal fluid after injection but casein (and the normal haemolymph proteins) are fully retained.
Human Intestinal Protozoal and Helminthic Infections observed in Malta
Authors: Bentham Thomas 
Published: June 2009

The following observations are the result of two years' examination of the stools of patients invalided to and stationed in Malta. The patients may be roughly divided for convenience into four groups:(1) Troops sent straight from the Salonika Hospitals to Malta. This section comprised the bulk of the total number of troops examined, and included a few men from Egypt.(2) Garrison Troops—some not patients—including both British and Maltese. With these are included a few British and Maltese Civilians,. connected in some way or another with the Army.(3) Troops on their way out from England or France. These were mostly Indians and Chinese, who were put off transport at Malta owing to disability.(4) Prisoners of War interned in Malta.
Studies on the Influence of the Environment on the Sheep Blow-fly, Lucilia sericata Meig
Authors: Evans A. C. 
Published: June 2009

Prepupae and pupae are shown to lose weight more rapidly at low than at high humidities. This more rapid loss of weight is due to loss of water alone and not to loss of dry matter.The limits of temperature and humidity which each of the two stages can survive have been mapped out. If the metamorphic period as a whole is considered, it is likely that the limits of temperature and humidity for survival and development will be narrower than for each stage considered alone.