bluuebunny/crossref_metadata_2025_split huggingface dataset:
Daily egg production of Ascaris lumbricoides: the distribution of eggs in the faeces and the variability of egg counts
Authors: Sinniah B. 
Published: June 2009

SUMMARYFifteen children aged from 6 to 12 years who were infected with Ascaris lumbricoides were selected for the study. The number of eggs/g (e.p.g.) of stool was determined using Beaver's direct smear technique, Stoll's dilution egg count technique and Katz's modified thick smear technique. Beaver's direct smear method consistently gave a higher e.p.g. than the other two methods. Results of this study show that Katz's modified thick smear technique was the best of the three methods used. The e.p.g. depends on several factors: the amount of stool passed daily, the concentration of eggs within a stool sample, the daily egg output, the worm load, the age of the worm and the technique used for determining the egg load. The daily average egg output/female A. lumbricoides was estimated to be 238722 (range 134462–358 750) with an average e.p.g. of 3540. The estimation of worm load based on egg count is useful in determining the intensity of infection in an individual. The male/female worm ratio was estimated to be 1: 1·4.
Factors influencing the assessment of anticoccidial activity in cell culture
Authors: Latter Victoria S. , Wilson R. G. 
Published: June 2009

SUMMARYA comparative study has been made of the factors influencing the assessment of anticoccidial potency in vitro against Eimeria tenella using established anticoccidials and arprinocid and some of its analogues. Drugs whose potency depended upon medium composition were amprolium, lasalocid and halofuginone. There was a difference in strain sensitivity with robenidine. Host cell type had an important effect on potency of monensin, decoquinate, arprinocid and its analogues. Arprinocid was active in chick liver cell systems but totally inactive in chick kidney cell systems, although its N-oxide was active in both cell types. Arprinocid-containing medium, conditioned by supporting the growth of chick embryo liver cell cultures, had an anticoccidial effect on E. tenella, growing in chick kidney cells. It is deduced that the anticoccidial activity of arprinocid in the chick is due to a metabolite.
The ultrastructure of the intestine of the redia of Parorchis acanthus Nicoll (Digenea: Philophthalmidae) from the digestive gland of Nucella lapillus L
Authors: Rees F. Gwendolen 
Published: June 2009

SUMMARYThe intestine of the redia of Parorchis acanthus is lined by a gastrodermis and surrounded by inner longitudinal and outer circular muscles. The gastrodermis consists of alternating rings of dense and lucent cells of similar dimensions, with similar nuclei and with microvilli on the lumenal surface. The dense cells contain ribosomes, dense secretion bodies, vesicles and a few lipid bodies. Ribosomes, dense bodies and lipids are absent from the lucent cells but vesicles are present which, as in the dense cells, pass along the microvilli to be discharged into the lumen. Both types of cells are secretory, absorptive and transportive. The lucent cells, in addition, store glycogen in areas of the cytoplasm devoid of organelles. Tips of processes from the parenchyma cells are engulfed in pockets in the basal plasma membrane, of both, facilitating transport of nutrients from the gastrodermis directly into the parenchyma
The migration, growth and development of Cyclocoelum oculeum (Kossack, 1911) (Trematoda: Cyclocoelidae) in Fulica americana (Gm.)
Authors: McLaughlin J. D. , Marcogliese D. 
Published: June 2009

SUMMARYThe migration, growth and development of Cyclocoelum oculeum Kossack, 1911 was studied in orally and parenterally exposed coots, Fulica americana (Gm.). Young flukes injected into the body cavity migrate to the sinuses from the body cavity via the air sacs and air passages. Young flukes were first found in the trachea on day 18 post-infection and in the sinuses on day 21. Migration was not synchronous and some flukes were found in the air sacs and trachea of parenterally exposed coots up to 45 days post-infection. Exponential growth and organogenesis began between days 9 and 12. Flukes in the sinuses were consistently larger than flukes of the same age in either the air sacs or trachea. Growth and organogenesis proceeded in the latter flukes but at a slower rate than those in the sinuses.
Allosteric control of pyrimidine transport in Hymenolepis diminuta: an unusual kinetic isotope effect
Authors: Uglem G. L. , Dupre R. K. , Harley J. P. 
Published: June 2009

SUMMARYA thymine–uracil transport system is present in the plasma membrane brush-border of the tapeworm, Hymenolepis diminuta. The relation between initial uptake and substrate concentration of either thymine or uracil was sigmoidal when 2-14C-labelled substrates were used. In contrast, absorption kinetics of methy 1-14C- and 3H-labelled substrates were hyperbolic. Since there was no metabolism of the labelled substrates during the incubation period, these differences indicate that the sigmoidal kinetics of pyrimidine transport in this organism is an isotope effect associated with the presence of the 14C label at the 2 position in the pyrimidine ring.
Re-discovery of Haemoproteus kopki (De Mello, 1916) in two geckoes from the Afghan border of Pakistan
Authors: Telford Sam R. 
Published: June 2009

SummaryHaemoproteus kopki (De Mello, 1916) is reported from the geckoes Teratoscincus scincus and T. microlepis collected in three localities on the Afghan border of Pakistan. A detailed description of H. kopki is provided in correlation with the courses of an initial, acute infection and a relapsed, chronic infection. Haemoproteus kopki is characterized by large round or oval gametocytes which show sexual dimorphism in distribution of pigment: macrogametocytes show pigment dispersed in dark granules throughout the cytoplasm, while pigment in microgametocytes is aggregated into large, round golden masses within vacuoles in one, or rarely two foci. Other sexual differences exist in gametocyte dimensions. Gametocytes produced in the relapse infection grew much more slowly than did those of the initial infection, and never attained a comparable size despite being observed for twice the length of time. Despite a maximum parasitaemia of 53·8% in the initial infection, increased erythropoiesis did not occur. No asexual stages were found in tissues examined. The presence of mixed infections of H. kopki, Leishmania sp. and microfilariae in a harsh sand dune habitat with presumably limited dipteran fauna suggests their having a common vector in intimate association with the burrows inhabited by the geckoes.
Suppression of the immune response to Trichuris muris in lactating mice
Authors: Selby Gwendoline R. , Wakelin D. 
Published: June 2009

Mice infected with Trichuris muris during lactation were unable to expel the infection at the normal time, but expulsion occurred when lactation was terminated. Suppression of expulsion was uniform in mice suckling more than five young but variable with smaller litters. Mice exposed to a primary infection while lactating were shown to have serum antibodies capable of passively transferring immunity to recipient mice and showed near normal immunity to a secondary infection given after lactation had ceased.Acquired immunity to T. muris was also suppressed by lactation, but the worms which became established in lactating resistant mice were fewer and smaller than those in non-lactating, non-resistant controls.It is suggested that the suppressive effect of lactation in this hostparasite relationship is exerted on the second, lymphoid cell-mediated phase of worm expulsion.
Evasion of the insect immune response by Moniliformis dubius(Acanthocephala): further observations on the origin of the envelope
Authors: Lackie Ann M. , Lackie J.M. 
Published: June 2009

SUMMARYThe envelope around larvae of Moniliformis dubius appears to protect the parasite against immune recognition and encapsulation by the insect host's haemocytes. The origin of this envelope has been the subject of controversy although most evidence suggests it is parasite-derived. If host-derived, the envelope would be expected to share surface properties with host tissue. Thus, experiments were undertaken, transplanting parasites and host tissue to other insects and using haemocytic encapsulation as an assay for immune recognition, in order to compare the response to host tissue and to the parasite's envelope. Parasites without their envelopes, and pieces of tissue (ventral nerve cord) from the experimental host (the locust Schistocerca gregaria) were recognized as foreign and encapsulated in the cockroach, Periplaneta americana. The majority of parasites with their envelopes were unencapsulated or only partially encapsulated on transfer to their normal host, P. americana, indicating that the envelope does not have surface similarity to locust tissue. Cockroach-derived parasites with or without envelopes were not encapsulated in S. gregaria, suggesting that the larva itself can evade or inhibit the locust's recognition mechanism. However, since larvae which develop in S. gregaria are enclosed in an envelope, the formation of the envelope would seem to be an inherent feature of the parasite's development.
A monoclonal antibody toBabesia divergenswhich inhibits merozoite invasion
Authors: Winger Caroline M. , Canning Elizabeth U. , Culverhouse J. D. 
Published: June 2009

SUMMARYA monoclonal antibody-producing hybridoma cell line has been raised against merozoites ofBabesia divergens. This antibody is strongly reactive against merozoites in an enzyme-linked immunosorbent assay (ELISA) and is also positive in an indirect fluorescent antibody test (IFAT) on preparations of live merozoites. The antibody recognizes an antigen, of molecular weight (Mr) 50–60 K by Western blot analysis on SDS–polyacrylamide gel electrophoresis (SDS–PAGE) gels. Merozoite neutralization assays show that the antibody significantly inhibits merozoite invasion of bovine erythrocytes.
Control of insects by bacteria
Authors: Burges H. D. 
Published: June 2009

SUMMARYAll bacteria in microbial insecticides are species ofBacillusand form spores since they have to survive in the environment and on the shelf. They can be formulated as wettable powders, suspensions and dusts for application with conventional pest control machinery. All are safe to man and virtually all non-target organisms. Development costs are relatively low, but host specificity greatly restricts markets, the largest beingca. 2000 tons per annum in the West forB. thuringiensis. All act only after ingestion, a disadvantage because there is no contact action and usually only larvae are attacked. Three main groups have special features that determine their commercial success.TheB. popilliaegroup is produced onlyin vivowhich limits production by three small firms. The Japanese beetle has been controlled in grassland in the warm parts of the USA by single applications of spores in heaps, spaced 2 m each way. The bacterium spreads slowly to untreated areas, is very persistent and kills only by infection.TheB. thuringiensisgroup kills larvae of Lepidoptera, mosquitoes and blackflies, mainly by gut poisoning with a protein crystal toxin. It rapidly paralyses mouthparts and gut, stopping crop damage. It is readily produced by deep liquid fermentation, but does not persist and needs repeated application during the pest season. Products containing no beta exotoxin can be applied at unlimited dosage to food crops up to harvest. Only one application is needed for stored grain. After 20 years' use of strains against Lepidoptera, a different strain is now used commercially against mosquitoes and blackflies (only 5 years after its discovery), although improvements in formulation for aquatic application are needed. A recent new product based on the beta exotoxin is used in Finland only against flies in pig houses because it has some vertebrate toxicity.TheB. sphaericusgroup is similar toB. thuringiensis, except that its proteinaceous toxin is different, is situated in the spore wall in strain 1593, and attacks only mosquitoes. Now at the pilot production stage, its commercial future depends on whether it is more potent thanB. thuringiensisagainst certain species and whether it can recycle to give effective extended mosquito control in some environments.Intensive selection from natural isolates has improved potency 100 to 600 fold. This selective effort must be maintained and improved by genetic manipulation, which can be used to develop greater potential, particularly since DNA coding for the crystal toxin is carried on plasmids. This also gives speculative hope that the toxin may be incorporated into natural aquatic bacteria for mosquito control and into plants for protection against lepidopterous larvae. A great advantage is that these bacteria do not harm beneficial fauna to cause pest resurgence. At present, the main use lies in integrated pest control systems, although bacteria are not likely to supplant chemical insecticides on a large scale in the near future.
Excystation of Notocotylus attenuatus (Rudolphi, 1809) Kossack, 1911 (Trematoda: Notocotylidae) and their localization in the caecum of the domestic fowl
Authors: Radlett A. J. 
Published: June 2009

SUMMARYStudies on the biology of Notocotylus attenuatus in the domestic fowl were undertaken with the aim of determining where in the alimentary system the metacercariae excyst and how soon the juvenile worms become established in the caecum of the host. The metacercariae were found to excyst in the lower intestine and juvenile worms were recovered from the caecum after 4 h. Thereafter, as the worms increased in size they changed their position relative to the viii and also moved down the caecum, coming to lie in the blind ending region as the worms approached maturity.
Observations on the development and survival of the free-living stages ofHyostrongylus rubidusboth in their natural environments out-of-doors and under controlled conditions in the laboratory
Authors: Rose J. H. , Small A. J. 
Published: June 2009

SUMMARYFaeces containing eggs ofHyostrongylus rubiduswere deposited on grass plots each month throughout 1980. Eggs in faeces deposited on plots from May to October developed into infective larvae but in May development was completed only in artificially moistened faeces, the weather was warm and dry and natural faeces dried out rapidly resulting in the death of eggs and pre-infective larvae. For the remainder of this period the weather was sufficiently warm and wet for development to be completed. More eggs developed into infective larvae on plots with well-grown herbage than on plots with short herbage. In April a few eggs survived and developed into lst-stage larvae but no further development took place. In the laboratory development was completed at temperatures ranging from 10 to 27 °C but no development took place at 4 °C. Out-of-doors infective larvae survived on herbage for up to 10 months while in the laboratory, infective larvae suspended in tap water survived even longer at 10 and 22 °C, but the larvae were rapidly killed by continuous freezing and by desiccation when the relative humidity was less than 95%. The relationship between climatic conditions and the development and survival of the free-living stages is discussed and a comparison made with the free-living stages ofOesophagostomum dentatum.
Rohdella siamensis gen. et sp.nov. (Aspidogastridae: Rohdellinae subfam.nov.) from fresh water fishes in Thailand, with a reorganization of the classification of the subclass Aspidogastrea
Authors: Gibson D. I. , Chinabut S. 
Published: June 2009

SUMMARYRohdella siamensis, a new genus and species of aspidogastrean, is described from freshwater fishes in Thailand. A new subfamily, the Rohdellinae, is erected to accommodate this worm on the grounds that it differs from all known aspidogastreans in that the male and female ducts unite to form an hermaphroditic duct, with the result that the intromittent organ is a sinus-organ and not a cirrus. A new classification of the subclass Aspidogastrea is presented. Two orders are recognized: the Aspidogastrida, containing a single family, the Aspidogastridae, which in turn contains 3 subfamilies, the Aspidogastrinae, the Cotylaspidinae and the Rohdellinae subfam.nov.; and the Stychocotylida ord.nov., containing 3 families, the Stichocotylidae, the Multicalycidae fam.nov. and the Rugogastridae. The systematic position of the Stichocotylida, and especially the Rugogastridae, is commented upon.
A stereological analysis of the tegumental mitochondria in Corrigia vitta (Trematoda: Dicrocoeliidae)
Authors: Robinson R. D. , Halton D. W. 
Published: June 2009

SUMMARYThe tegumental mitochondria from the anterior, mid-ventral and mid-dorsal regions of the body surface of Corrigia vitta have been analysed using stereological and statistical methods. Mitochondria from the ventral tegument were more numerous and contained a greater density of cristae than either the anterior or dorsal tegumental mitochondria. A close association between the size and numbers of mitochondria in the anterior regions of tegument appears to be important in maintaining a relatively constant mitochondrial volume fraction. Results are discussed with respect to worm surface function in the intact host-parasite system.
Eimeria tenella: in vitro development in irradiated bovine kidney cells
Authors: Crane M. St J. , Schmatz D. M. , Stevens S. , Habbersett Mary C. , Murray P. K. 
Published: June 2009

SUMMARYThe initial infection and first-generation development of Eimeria tenella was quantified using a cloned MDBK (Madin-Darby Bovine Kidney) cell line, irradiated with gamma radiation prior to infection, as the host cell. Irradiated cell cultures were found to be more susceptible to infection and had a greater capacity to support parasite development than non-irradiated cultures. It was suggested that the larger proportion of cells in the G2 phase of the cell cycle, the larger individual cell size and the inhibition of cell division in the irradiated cultures were all factors contributing to the increased susceptibility to infection and capacity to support parasite growth and development. The application of this technique (host cell irradiation) to the cultivation of other intracellular, protozoan parasites is discussed.
The ultrastructural development of the oocyst wall of Eimeria maxima
Authors: Pittilo R. M. , Ball S. J. 
Published: June 2009

SUMMARYOocyst wall formation in Eimeria maxima was studied during the macrogamete stage in intestinal cells of the chick and in unsporulated oocysts isolated from faeces. The outer of the 2 membranes bounding the mature macrogamete separated from the surface but remained as a veil surrounding the developing oocyst throughout the whole intracellular process. Wall-forming bodies Type I were initially applied to the limiting membrane of the zygote cytoplasm; a layer of material similar to their contents was then formed around the zygote. As this occurred a new double membrane was formed surrounding the oocyst cytoplasm. The outer wall layer was initially homogenous in appearance but later developed into 2 zones, an outer amorphous region and an inner osmiophilic region. The inner layer of the oocyst wall was formed from the contents of the wallforming bodies Type II which dispersed between the outer wall and the limiting membranes of the oocyst cytoplasm. There was evidence of an additional membrane formed external to the outer wall. The outer membranes were not present around the wall of oocysts passed in the faeces of chicks, but the same wall zonation was evident, although the inner osmiophilic zone of the outer wall layer was markedly thinner in comparison with the same zone seen in the tissues.
The development of Theileria = Cytauxzoon taurotragi (Martin and Brocklesby, 1960) from eland in its tick vector Rhipicephalus appendiculatus
Authors: Young A. S. , Grootenhuis J. G. , Leitch B. L. , Schein E. 
Published: June 2009

SUMMARYThe sexual cycle of Theileria taurotragi was identified in the gut lumen of replete Rhipicephalus appendiculatus nymphs maintained at 28°C which had fed on eland with rising parasitaemias. Macro- and microgametes developed from ring-form piroplasms within 24 h after repletion. The microgamonts were elongate with 2 or more lateral projections. The nuclei of the microgamonts divided into 4 and the microgamonts differentiated into 4 thread-like microgametes each with a central nucleus. Round macrogametes developed at the same time and stages indicative of the fusion of the macro- and microgametes were observed after 48 h. The resultant zygotes were detected in the gut wall cells by day 4, many being rounded and vacuolated with a peripheral nucleus. By day 7 the zygote cytoplasm became dense and they lay in clusters still within the cells. Binucleate zygotes were observed at this stage. The zygotes increased in size and by day 12 began to transform into kinetes by invagination. By the time the nymphs moulted into adults (about day 14), the kinete straightened to a broad anterior end and a tapering posterior with a mean length of 22·1 μm. Kinetes were detected in the haemolymph by day 16. By day 20 the kinetes had penetrated the salivary gland acinar cells where they underwent schizogony until the infected acinar cells were filled with multinucleated sporoblasts. The nuclei of the infected acinar cells became greatly enlarged soon after penetration of the kinete. Division of the sporoblast nuclei was stimulated by feeding of the adult ticks. From the 2nd day of attachment of the ticks to rabbits the sporoblasts underwent a process of schizogony to produce cytomeres. Each nucleus of the cytomere divided to produce several small nuclei which differentiated into uninucleated sporozoites.
Interaction of epimastigote and trypomastigote forms ofTrypanosoma cruziwith chicken macrophagesin vitro
Authors: de Meirelles M. N. L. , de Araujo Jorge T. C. , de Souza W. 
Published: June 2009

SUMMARYChicken macrophages, obtained by cultivation of blood monocytes, were infected with epimastigote and bloodstream trypomastigotes of the Y and the CL strains ofTrypanosoma cruzi. The percentage of infected cells and the mean number of parasites per cell were determined after 2, 6, 12 and 24 h of parasite–cell contact. After 6 h of contact about 80% and 40% of the macrophages were infected by trypomastigotes of the Y and CL strains respectively. After longer periods of contact almost all macrophages were infected by Y trypomastigotes while only about 60% were infected by those of the CL strain. After 2 h of contact almost all macrophages were infected by CL epimastigotes while only about 50% were infected by Y epimastigotes. After 6 h of contact almost all macrophages were infected by epimastigotes of both strains. These results are discussed taking into consideration differences between parasites of the two strains and between the two developmental stages of theT. cruzilife-cycle.