bluuebunny/crossref_metadata_2025 huggingface dataset:
The functional morphology of the genitalia of the spermato-phore-producing monogenean parasite Diplectanum aequans (Wagener) Diesing, with a note on the copulation of the parasite
Authors: Paling J. E.
Published: June 2009

The genitalia of Diplectanum aequans (Wagener) Diesing are described and a functional interpretation is postulated.

Spermatophores are produced from a pair of diffuse glands lying laterally amidst the vitellaria. The secretion from these glands is stored in an anterior reservoir, across the centre of which is a viscous disk which delineates two internal chambers.

Each spermatophore has an elongated stalk and an ovoid head and is considered to be moulded in a muscular bulb and in the penis, prior to extrusion through the penis.

The penis is composed of two concentric tubes and it has a slight hook at its distal end. The vagina has a glandular base and muscular lips. Its internal cast corresponds to the shape of the penis tip.

Copulation in D. aequans is described.

The occurrence and biological significance of spermatophore production in animals are discussed.

I would like to acknowledge the help given to me by the Director and Staff of the Marine Biological Association Laboratory and also by the Proprietors of Cook and Sons Ltd., of Salcombe, Devon. I am most grateful to Dr J. Llewellyn for much helpful advice throughout the course of this study.

The work was conducted during the tenure of a D.S.I.R. Studentship and includes the results of special studies made possible by a grant from The Browne Fund of The Royal Society.
The structure and chemical composition of the nematode cuticle. Observations on some oxyurids andAscaris
Authors: Anya A. O.
Published: June 2009

Studies of the cuticle ofAspiculuris tetrapterawith both the light and the electron microscopes have shown that there are three basic layers, namely the cortex, which consists of an outer and an inner layer, the matrix layer and the fibre layer; the latter is made up of three layers. There is, in addition, a thin osmiophilic superficial membrane on the surface of the cuticle; this membrane is seen only with the electron microscope.

It is shown that the major structural protein of the cuticle, although showing no axial periodicity, is collagen; the collagen is associated with hyaluronic-acid- and chondroitin-sulphate-containing mucopolysaccharides.

Evidence is presented for the existence of two centres of protein synthesis (collagen fibrogenesis) in the cuticle ofA. tetraptera, Syphacia obvelataandAscaris lumbricoides.These centres are located in the inner cortex and the hypodermis. The cuticle is thus very active metabolically.

I wish to acknowledge with thanks the facilities afforded me at the Molteno Institute during the course of these studies by the Director, Dr P. Tate. My thanks are also due to Dr D. L. Lee for his encouragement and helpful discussions during the investigations.
Properties of DNA from some malarial parasites
Authors: Gutteridge W. E. , Trigg P. I. , Williamson D. H.
Published: June 2009

The base compositions of DNA from some species of malarial parasite have been estimated by measurement of density in CsCl gradients and of thermal denaturation temperatures. Species from avian (Plasmodium gallinaceum) and rodent (P. bergheiandP. vinckei) hosts – often used as model systems in malarial studies – contain single DNA components with base compositions of about 20% G + C. By contrast, species from primate hosts (P. knowlesiandP. falciparum) contain major DNA components of about 40% G + C and minor ones of about 20% G + C. These differences could be reflexions of markedly different genomes within these two groups of the genusPlasmodium.

Apart from differences in base composition, the physico-chemical properties of the main components of DNA from primate and rodent malarial parasites are very similar to those of DNA from mammalian cells. DNA from avian malarial parasites appears to have some unusual properties.

One of us (P.I.T.) received financial assistance from the World Health Organization. We thank Dr F. Hawking and Dr J. Williamson for many helpful discussions, Dr W. H. G. Richards, Dr A. Voller and Dr D. C. Warhurst for the provision of some of the strains and Miss Jane Dunnett, Mrs A. C. Gutteridge and Mr T. Scott-Finnigan for technical assistance.
Studies on gut ultrastructure and digestive physiology in Rhabdias bufonis and R. sphaerocephala (Nematoda: Rhabditida)
Authors: Colam J. Barry
Published: June 2009

Histological, histochemical and ultrastructural methods have been used to study gut structure and digestive physiology in the parasitic nematodes Rhabdias bufonis (Schrank, 1788) and R. sphaerocephala (Goodey, 1924). Both species are parasitic in the lungs of their amphibian hosts and feed entirely upon blood drawn from the lung capillaries.

Three gland cells are present in the oesophagus, one in each sector. The two subventral ducts open, by way of ampullae, into the lumen of the oesophagus about a quarter of its length from the anterior end. The dorsal gland opens similarly into the base of the buccal capsule. It is suggested that the glands produce a B-esterase, in an histochemically inactive form in situ, which is responsible for haemolysis and the bulk of extracellular digestion. Only one cell type is present in the intestine and this is entirely absorptive in function.

The major part of haemoglobin digestion is extracellular, partly by a process of contact digestion involving the B-esterase and acid phosphatase which are present in association with the microvilli. Haematin results from this process and is precipitated in the gut lumen. A smaller proportion of haemoglobin is taken up by the gut cells and is broken down intracellularly by lysosomes, originating in Golgi in the basal gastrodermis. These show endopeptidase activity and later acid phosphatase in some of the bodies of the lysosomal sequence and only at the light microscope level. The iron-containing pigment haemosiderin resulting from digestion is retained in the lysosome residues and forms the pigment granules in the gastrodermis. The products of extracellular digestion absorbed by the gastrodermis are synthetized into lipid by a lipase, probably produced by GER.

This investigation was supported in part by Research Grant AI 06295 of the United States Public Health Service. The final manuscript was prepared during the tenure of a Postdoctoral Fellowship from the British Egg Marketing Board. I wish to extend my gratitude to Dr J. B. Jennings for advice and encouragement throughout this work.
Opecoelid trematodes of marine fishes of India
Authors: Hafeezullah M.
Published: June 2009

The present study includes five new and three known species of trematodes from marine fishes of India. Records of new hosts and new localities are given. The new species are: Plagioporus longicaudus, Opegaster paramacrorchis, Pseudopecoelina elongata, Pseudopecoeloides scomberi and Hamacreadium leiognathi. The known species are: Podocotyloides parupenei (Manter, 1963) Pritchard, 1966, Hamacreadium mutabile Linton, 1910 and H. krusadaiensis Gupta, 1956. Hamacreadium leiperi Gupta, 1956 is considered a synonym of H. mutabile.

The author wishes to express his gratefulness to Dr Ather H. Siddiqi for his guidance and to Professor H. W. Manter of the University of Nebraska, U.S.A. for his valuable comments. The present study was financially supported by the Council of Scientific and Industrial Research, New Delhi.
A new species of Hoplopleura from Thailand, with notes and description of nymphal stages of Hoplopleura captiosa Johnson (Anoplura)
Authors: Kim Ke Chung
Published: June 2009

The adult stage and nymph 2 of Hoplopleura johnsonae sp.nov. and the nymphal stages of H. captiosa Johnson are described. The morphology of Hoplopleura nymphs and the infraspecific variations of H. captiosa Johnson are discussed, and a key to the seven species of Hoplopleura Enderlein known in Thailand is also presented.

I am grateful to Dr K. C. Emerson, Arlington, Virginia, and Dr Zofia Wegner, Gdansk-Wrzeszcz, Poland, for the loan of materials on which this work was based. I am also indebted to Dr Phyllis T. Johnson, University of California at Irvine, and Dr Edwin F. Cook, University of Minnesota, for their suggestions as to this species complex and reading the manuscript.
Experimental studies on the physiology of hatching of eggs ofAspiculuris tetrapteraSchulz (Oxyuridea: Nematoda)
Authors: Anya A. O.
Published: June 2009

An experimental study of hatching in the oxyurid nematodeAspiculuris tetrapteraindicates that the major factors in the initiation of hatching are the pH and temperature of the environment and that the process is aerobic. Carbon dioxide and reducing agents do not appear to be as important factors in the hatching of eggs of this nematode as they are in the hatching of eggs of ascarids. It is suggested that the physiology of hatching in ascarids is not necessarily the typical nematode pattern.

My grateful thanks are due to Dr P. Tate, Director of the Molteno Institute, and to Dr D. L. Lee for their encouragement and very helpful discussions on various aspects of this study.
The ultrastructure of the daughter sporocyst of Cercaria bucephalopsis haimaena Lacaze-Duthiers, 1854 (Digenea: Bucephalidae) from the edible cockle, Cardium edule L.
Authors: James B. L. , Bowers E. A. , Richards J. G.
Published: June 2009

The body wall of the daughter sporocyst of Cercaria bucephalopsis haimaena Lacaze-Duthiers, 1854, is shown by the electron-microscope to consist of an external syncytial tegument, lying on a basement membrane, and an internal cellular subtegument, which surrounds a body cavity containing developing cercariae.

The syncytial tegument has areas of dense cytoplasm alternating with sparse reticulate cytoplasm. The dense cytoplasm contains nuclei, a few mitochondria and secretory products which probably include a neutral mucopolysaccharide. This may be the precursor of the acid mucopolysaccharide in the sparse reticulate cytoplasm and on the surface of the daughter sporocyst.

Nutrients are probably absorbed through the outer plasma membrane of the tegument, pass through the sparse reticulate cytoplasm in the middle region of the tegument, the inner plasma membrane and basement membrane into the subtegument.

The ultrastructure of the tegument of adult and larval Digenea are compared.

We would like to thank Dr Gwendolen Rees for allowing us to examine the electron-micrographs of Parorchis acanthus. We are also grateful to Professor E. W. Knight-Jones for the provision of excellent working facilities and to the Science Research Council, for a grant to one of us (E.A.B.) which made the work possible.
Histochemical observations on the occurrence of carbohydrates, lipids and enzymes in the daughter sporocyst of Cercaria bucephalopsis haimaena Lacaze-Duthiers, 1854 (Digenea: Bucephalidae).
Authors: James B. L. , Bowers E. A.
Published: June 2009

The distribution of carbohydrates, lipids and enzymes in the daughter sporocyst and contained cercariae of Cercaria bucephalopsis haimaena Lacaze-Duthiers, 1854, is mapped and used as an indication of metabolism. It is concluded that host glucose, glycogen, fatty acids and neutral lipids are absorbed and pass through the syncytial tegument into the cellular sub-tegument. They are then either metabolized or passed into the body cavity and contained cercariae. Glucose seems to be either converted into glycogen and glycoproteins or metabolized anaerobically. The end products of anaerobic respiration are fatty acids and neutral lipids. These pass into the excretory system, which flushes them into the body cavity of the daughter sporocyst, from where they enter the body of the developing cercariae. In the cercariae they are deposited, together with host lipids, possibly as less toxic higher fatty acids or other stored lipids. The stored glycogen and lipids in the cercariae are probably utilized aerobically during the free-living existence. The transport of nutrients and excretory products across the cell membranes may be aided by alkaline phosphatase and esterase activity, as is the metabolism of carbohydrates and lipids. Acid mucopolysaccharide precursors appear to be synthesized in the dense cytoplasm of the mid-tegument of the daughter sporocyst and secreted into the host's visceral haemocoel. Acid phosphatase and esterase found in this region may be involved in the synthesis and also in the breakdown of complex incoming nutrients.

We are grateful to Professor E. W. Knight-Jones for laboratory facilities and to the Science Research Council for a grant to one of us (E. A. B.) which made the work possible.
Studies on the haemocytic reaction ofGammarusspp., and its relationship toPolymorphus minutus(Acanthocephala)
Authors: Crompton D. W. T.
Published: June 2009

The haemocytes ofGammarus, which are part of the environment ofP. minutes, have been found to react by encapsulation, against a variety of foreign bodies, wounded tissues and interspecific transplants. Cuticular wounds appear to present the most urgent stimulus to the haemocytes. The haemocytic reaction is not suppressed by X-irradiation. Differences in haemolymph salt concentration betweenG. pulexandG. duebenido not appear to be responsible for the failure of transplants of tissue fromG. pulextoG. duebeni.It is concluded that the haemocytic reaction ofGammarusis very similar in response and nature to that of insects.

HealthyP. minutusdoes not stimulate the haemocytic reactions of its hosts, but wounded or damaged parasites are encapsulated. The capsule of connective tissue, which surrounds the parasite during its development in the haemocoele of the intermediate host, appears to be essential for the parasite's survival.

I am most grateful to Dr P. Tate for helpful discussions, and Dr George Salt, F.R.S., for his advice and criticism of the manuscript. I also wish to thank Drs H. Laser and B. E. B. Moseley for irradiating the amphipods for me.
The fine structure of the trunk and praesoma wall ofAcanthocephalus ranae(Schrank, 1788), Lühe, 1911
Authors: Hammond R. A.
Published: June 2009

The wall of the trunk, that of the praesoma, and the lemnisci ofAcanthocephalus ranaehave been studied by electron microscopy. Striations visible in sections of the body wall under the light microscope do not correspond with the ‘striped layer’ revealed by the electron microscope.

A new region, the ‘canal layer’, has been described. This contains canals running into the body wall from cuticular pores.

Structurally the wall of the trunk and that of the praesoma are similar. The lemnisci resemble the ‘inner layer’ of the praesoma wall. However, it is suggested that the wall of the trunk differs physiologically from that of the praesoma, and from the lemnisci. The possible roles of the wall of the praesoma and the lemnisci in fat excretion or uptake have been discussed.

The body wall ofA. ranaehas been compared with that of the other acantho-cephalans studied with the electron microscope.

Grateful acknowledgement is made to D.S.I.R. (now S.R.C.) for a research grant to the Department of Zoology for the purchase of a Huxley ultramicrotome, a vacuum coating unit, and an AEI EM 6 electron microscope.

I am grateful to Dr D. A. Erasmus for reading and criticizing the manuscript, and to Mr T. Davies for valuable technical assistance.
On a monostome parasite of Indian domestic fowl with remarks on the genus Notocotylus Diesing, 1839
Authors: Nath Dharmendra , Pande B. P.
Published: June 2009

Notocotylus is reported in Indian domestic fowl and the specimen assigned to the species N. attenuatus. The literature on this monostome genus is briefly reviewed and need for an examination of type specimens of some of its species is stressed.

Thanks are due to the Principal of the college for facilities provided and to the head of the Zoology Department, Lucknow University, for loan of some literature.
Studies on two new coccidia from the Venezuelan lizardCnemidophorus lemniscatus lemniscatus: Hoarella garnhamigen.nov., sp.nov. andEimeria flaviviridis americanasubsp.nov.
Authors: de Peraza Lucila Arcay
Published: June 2009

This work contains the description of two new Coccidia parasitic in the South American lizardCnemidophorus lemniscatus lemniscatus. One is identified asEimeria flaviviridis americanasubsp.nov., which is described and discussed in relation to the other species recorded from sauria. The other isHoarella garnhamigen.nov., sp.nov., whose position in the family Eimeriidae necessitated a revision of the classification of the Coccidia Eimeriidae.

I wish to acknowledge the help and encouragement I received from Professor P. C. C. Garnham, in whose department this work was carried out. My thanks are also due to Dr Cecil Hoare for his private communications and assistance in the interpretation of histological specimens. The author is grateful for co-operation of the School's Photograph Staff and to members of the staff of the Department of Parasitology, especially to Mr P. E. Nesbitt for his valuable sections. Finally, the author is indebted to the Consejo de Desarrollo Cientifico y Humanístico de la Universidad Central, Caracas, for their assistance in the form of a scholarship during the tenure of which this work was produced.
The larva of Psychoda (Philosepedon) humeralis Meigen (Diptera, Psychodidae)
Authors: Smith Kenneth G. V. , Grensted L. W.
Published: June 2009

Satchell (1947) described and keyed the larvae of 14 of the 19 British species of Psychoda, but this study did not include P. humeralis Mg., presumably because the author accorded generic rank to Philosepedon and Threticus which would put them outside his study of Psychoda sensu stricto. The larva of P. humeralis has been briefly described by Spärck (1920), but his figures are rather crude. A detailed treatment of the larval head is given by Anthon (1943). The present account is offered to facilitate identification of this species in the larval stage when used in conjunction with Satchell's comprehensive paper.
Electron-microscope studies of Fasciola hepatica III. Further observations on the tegument and associated structures
Authors: Threadgold L. T.
Published: June 2009

Additional ultrastructural features of the tegument of Fasciola hepatica, after glutaraldehyde fixation and high resolution, have been observed.

Two distinct types of tegumental cells are shown to be present, the type 1 cell having been previously described. Details of the fine structure of the nucleus, mitochondria, endoplasmic reticulum and Golgi complex of the type 2 cell are given. The type 2 cell is characterized by biconcave secretory bodies derived from the Golgi complex and the latter is intimately related to the granular endoplasmic reticulum, from which it is derived by blebbing. The type 2 cells are connected by protoplasmic tubes to the same surface syncytium as type 1 cells.

These new findings of the structure of the tegument of Fasciola are compared with previous reports on the ultrastructure of the tegument in other flukes.

I should like to express my sincere thanks to the following: the Wellcome Trust and S.R.C. for grants to purchase an Akashi TRS 50 and an A.E.I. E.M. 6B electron microscope respectively; the Royal Society for a personal grant to purchase a Reichert Ultramicrotome and a vacuum coating unit.

My thanks are also due to Mr W. Ferguson for photographic skill and to Mr A. Lyness for technical assistance and microscope maintenance, and my Research Associate, Mrs S. S. E. Dermott, for expert electron-microscopy.
Observations on the nutrition of digenetic trematodes
Authors: Halton D. W.
Published: June 2009

Both histological and histochemical studies have been made of the food, mode of feeding, gut cell structure and digestive sequences in a selected number of digenetic trematodes.

The species investigated range from gut-dwelling trematodes feeding on the superficial epithelial tissues and associated mucoid secretions of the host to those forms living within the respiratory and circulatory system and feeding exclusively on blood.

The mode of feeding is suctorial, brought about by the muscular pharynx and normal attachment process of the oral sucker. In one case there is evidence that this purely mechanical process is supplemented with enzymic secretions produced by the trematode which have a histolytic effect upon host tissues.

On the basis of gut cell structure the species investigated are divided into those with cells and associated microvilli that vary in size and appearance so that the gastrodermal border is irregular in outline, and those with a gastrodermis comprising regular cuboidal or columnar cells bearing microvilli organized into a striated border. There is evidence to suggest that this difference in gut cell structure reflects differences in digestion. In all cases, gland cells are absent from the gastrodermis which is capable of both secretory and absorptive functions.

Digestion is predominantly an extracellular process, but the exact sequence varies according to the nature of the food ingested and different degrees of adaptation are shown by the trematodes to the blood-feeding habit. The tissue-feeding species show less modification.

I wish to thank Dr J. B. Jennings for helpful discussion and advice throughout the course of this work. The study was undertaken during the tenure of a Studentship from the Department of Scientific and Industrial Research.
Observations on Transversotrema patialensis (Soparkar, 1924) (Trematoda) from Waltair, Andhra Pradesh (India)
Authors: Rao K. Hanumantha , Ganapati P. N.
Published: June 2009

Cercaria patialensis Soparkar, 1924, emerging from the snail Melanoides tuberculatus (Müller) has been encountered at Waltair. The cercariae begin to emerge from the snail at dusk and continue to do so during the period of darkness.

Stages resembling the adult but without the development of eggs have been encountered in nature on the fresh water fishes Panchax panchax (Ham. & Buch.) and Esomus danricus (Bleeker). These stages have also been raised experimentally by exposing P. panchax, E. danricus and fingerlings of Catla catla Ham. & Buch. to the cercariae.

The cercaria is referable to the genus Transversotrema Witenberg, 1944.

It is suggested that there may not be a metacercarial stage in the life-cycle of Transversotrema spp.
On the biology and morphology of Echinococcus granulosus (Batsch, 1786) of buffalo–dog origin
Authors: Gill Hardev Singh , Rao B. Venkateswara
Published: June 2009

The present material of buffalo–dog origin could not be transmitted to the laboratory animals, such as white rats, white mice, rabbits, golden hamsters, guinea-pigs and chicks.

Secondary development took place only in mice.

The strobilar phase was infective to a cat but did not show sexual differentiation even at 30 days, and worms were further observed to be at a degenerative stage.

The buffalo was highly suited to the perpetuation of the parasite, forming larger cysts and massive production of scoleces; nearly 90% of the cysts were fertile.

The strobila had mostly two segments and not more than three.

The number and distribution of testes were more posterior to the genital pore and were also observed posterior to the vitellaria, occasionally.

The position of the genital pore in the gravid as well as mature segments was both anterior and posterior but with an average of 52.8%.

Uterine sacculations were observed to range from 28 to 54.

Echinococcus material of buffalo–dog origin does not appear to fall into a definite ‘subspecies’ pattern. It is suggested that it be merely recognized as a further ‘mutant’, the existence of which can be accounted for on theoretical grounds.

The authors are thankful to the Director, Indian Veterinary Research Institute, and to Dr H. D. Srivastava, Head of Division of Parasitology, I.V.R.I., for providing the necessary laboratory facilities.
Some stylet cercariae and a microphallid type in British freshwater molluscs
Authors: Pike Alan W.
Published: June 2009

Cercaria helvetica XXXIII Dubois and the cercaria of Sphaerostoma bramae (Müll.) are redescribed and their metacercariae, which occur in various invertebrates, are described. Additional observations are made on C. parvus Khan and C. tarda Khan and their metacercariae, occurring mainly in arthropods, are described. C. wentloogensis sp.nov. has four pairs of penetration glands, a slender, thickened stylet 0·03 mm long and the flame-cell formula

2[(2 + 2 + 2) + (2 + 2 + 2)].

C. rumniensis sp.nov. has four pairs of penetration glands lying dorsally to the acetabulum, a slender thickened stylet 0·03 mm long and at least 20 flame cells arranged in pairs. C. octoglandulata sp.nov. is a virgulate species with four pairs of penetration glands, a partially thickened stylet 0·029–0·032 mm long and the flame-cell formula 2[(3 + 3 + 3) + (3 + 3 + 3)]. Each of these new species develops in sporocysts in the digestive gland of the prosobranch mollusc Bithynia tentaculata. A cercaria occurring in the digestive gland of B. tentaculata and assigned to the Microphallidae on the structure of its metacercaria is considered to encyst in the digestive gland without emerging. It bears no stylet or penetration glands and the cysts occur in the snail in exceedingly large numbers.

All of these cercariae were found in freshwater molluscs collected at the Wentloog level near Cardiff, South Wales.
Neurobiology of arthropod parasites
Authors: Harrow I. D. , Gration K. A. F. , Evans N. A.
Published: June 2009

Many medically important diseases of man are caused by blood-sucking arthropods which serve as vectors for a wide range of viral, bacterial, protozoal and nematode infections (Table 1). Furthermore, serious economic losses are caused by the numerous arthropod parasites which infect domesticated animals (for examples, see Table 2). Among these the ixodid hard ticks are particularly important and it has been estimated that the global cost of hard tick infections is $7000 million per annum (F.A.O., 1984). Not surprisingly, there have been strenuous efforts to control infections caused by arthropods.
Neuropeptides in the nematodeAscaris suum
Authors: Stretton A. O. W. , Cowden C. , Sithigorngul P. , Davis R. E.
Published: June 2009

Most of the successful anti-nematode drugs currently available affect the nematode locomotory system. Their success is due to their interactions with molecules associated with the main neuro-transmitters of the motor nervous system, acetylcholine and GABA. These drugs tend to have a relatively broad spectrum of action, affecting a wide variety of nematodes, presumably because nematode motor nervous systems are conservative in their use of these transmitters.
The immature stages of Ixodes tatei Arthur (Ixodidae)
Authors: Arthur Don. R.
Published: June 2009

The original description of Ixodes tatei was given by Arthur (1959) and based on three females taken from a rock partridge of unknown species and from a fox (Vulpes sp. ?) in Jarmo, Chemchemal Valley, Kirkuk (type locality) and the Zagros Mountains, Erbil, both in north-eastern Iraq. The material, on which the following account is based, consisted of two females, one gorged nymph, one slightly fed nymph and two fully gorged larvae. They were collected from the head of Alectoris graeca, which was shot about 20 km south of Jerusalem on 17 December 1966 and sent to me by Professor O. Theodor of the Hebrew University. One female, one nymph and one larva have been deposited in the Hebrew University, Hadassah Medical School, and one female, one nymph and one larva are retained in my collection. The holotype female is deposited in the Chicago Natural History Museum, Cat. no. 84472.
Evidence for the existence of ganglioside molecules onPneumocystis cariniifrom human lungs
Authors: Sorice M. , Lenti L. , Misasi R. , Contini C. , Cignarella L. , Griggi T. , Vullo V. , Masala C.
Published: June 2009

This study was undertaken to assess whether glycolipid antigens (particularly gangliosides) are associated withPneumocystis cariniiobtained from human lungs. Gangliosides were extracted, purified in high performance thin-layer chromatography and stained with resorcinol. Two resorcinol-positive bands, co-migrating with GM1and GD1awere demonstrated, suggesting the existence of ganglioside molecules onP. carinii. No resorcinol-positive bands were revealed in the pulmonary control tissue. In addition, an antiserum obtained from rabbits immunized withP. cariniiantigen reacted with gangliosides GM1, and GD1a, as revealed by a dot immunobinding assay. This reactivity was inhibited by first incubating the antiserum with ganglioside micelles. Furthermore, anti-glycosphingolipid antibodies (aGM1) reacted with the bands of 200 and 55 kDa ofP. cariniiantigen. These results suggest that ganglioside antigens expressed onP. cariniican trigger specific immune responses.
Schistosoma mansoni: praziquantel-induced tegumental lesion exposes actin of surface spines and allows binding of actin depolymerizing factor, gelsolin
Authors: Linder E. , Thors C.
Published: June 2009

Praziquantel is widely used for treatment of schistosomiasis. Elimination of intravascular worms involves a combination of drug-induced changes at the worm surface and a host immune response against exposed parasite components. Loss of spines is a typical feature of schistosomes obtained from praziquantel-treated infected animals. The mechanism for this is unknown. We have considered the possibility that praziquantel treatment involves exposure of surface spines consisting of ‘paracrystalline’ actin and a subsequent host response against actin through mechanisms established in the host independently from schistosomal infection. Drug-induced exposure of actin was demonstrated by fluorescence microscopy using anti-actin antibodies and phallacidin, an actin-binding mushroom toxin. Actin spines remained intact at the schistosome surface afterin vitroexposure, but spine morphology was lost afterin vivoexposure to praziquantel. Disintegration of spinesin vivowas associated with binding of host antibodies.In vitrospine destruction could be seen in the presence of normal human serum. The effect was linked to calcium-dependent binding of actin depolymerizing factor, gelsolin.
Observations on the free-living stages of the stomach worm Haemonchus contortus
Authors: Rose J. H.
Published: June 2009

Outdoor observations were made on the rate of development of the free-living stages of H. contortus at different times of the year, and on the migratory activities and longevity of the larvae in faeces, on herbage and in soil.

The effects of temperature and humidity on the survival and development of eggs and larvae, both in faeces and when separated from the faeces, were studied in the laboratory.

The results of these observations are discussed in relation to the heavy mortality of the free-living stages of H. contortus and to the transmission of infection in the field.
Morphological and histochemical observations onPolymorphus minutus(Goeze, 1782), with special reference to the body wall
Authors: Crompton D. W. T.
Published: June 2009

1. Certain aspects of the general morphology ofPolymorphus minutusare described together with a detailed description of the body wall.

2. An additional layer of the body wall, the epicuticle, has been demonstrated. It appears to consist of acid mucopolysaccharide and may have a function of protecting the parasite from the enzymes of its host.

3. A histochemical investigation has been made of the layers of the body wall and it is concluded that lipoprotein is one of the main structural components.

4. The distribution of the activity of the two enzymes, non-specific esterase and alkaline phosphatase, has been studied throughout the animal and the activity of a third enzyme, leucine aminopeptidase, has been detected in the body wall.

5. It is suggested that all the layers of the body wall, with the exception of the cuticle and epicuticle, are of metabolic importance. The striped layer may be connected with absorption and the felt and radial layers may be involved in the further metabolism of absorbed compounds.

6. The results obtained are used to formulate a possible structure of the surface of the parasite which would facilitate the absorption of nutrient substances through the body wall.

I am grateful to Dr P. Tate for advice and encouragement during this work, Dr R. J. Tatchell for helpful discussions, and Dr D. L. Lee for criticising the manuscript and Mr T. M. Warwick, Department of Zoology, University of Edinburgh for providing material.
Axenic cultivation and characterization ofLeishmania mexicanaamastigote-like forms
Authors: Bates P. A. , Robertson C. D. , Tetley L. , Coombs G. H.
Published: June 2009

A new method is described which has made possible the long-term axenic cultivation ofLeishmania mexicanaamastigotelike forms in Schneider'sDrosophilamedium supplemented with 2% (v/v) foetal calf serum. Unlike previous methods, it utilizes direct culture of parasites obtained from the lesions of infected animals rather than adaptation of promastigotesin vitro. Ultrastructural (possession of megasomes), biochemical (cysteine proteinase activity and gelatin SDS-PAGE banding pattern) and infectivity (in vivo) data are presented which show the close similarity of the cultured forms to lesion amastigotes. The axenically cultured forms grew optimally at a temperature of 32–33 °C, providing further evidence for their amastigote nature. It was found that adjustment of the pH of the growth medium to 5·4 was required in order to retain the amastigote morphology of the cultured parasites. This supports the notion that leishmanial amastigotes are acidophiles.
The dynamics of trickle infections withAncylostoma ceylanicumin inbred hamsters
Authors: Brailsford T. J. , Behnke J. M.
Published: June 2009

Trickle infections with a hamster-adapted strain of the hookwormAncylostoma ceylanicumwere studied by administering doses of 5–30 larvae twice weekly to inbred DSN hamsters. The worm burdens were regulated at very low levels, and this was found to be independent of the size of the infective dose. It is likely that there is some turnover of adult worms during trickle infection, as larvae of all stages were recovered from most time-points. This regulation is immunologically mediated and both the worm burdens and fecundity were increased in hamsters that were immunosuppressed by cortisone treatment. A trickle infection regime also induced a 67% protective immunity to a single subsequent challenge. The resistance that occurred during trickle infections was, however, incomplete, and some worms were found to survive in hamsters that had been repeatedly infected for over 10 weeks. Thus, although hamsters are capable of regulating the infection, some worms are capable of surviving the host immune effectors.
The use of suckling mice to isolate and growGiardiafrom mammalian faecal specimens for genetic analysis
Authors: Mayrhofer G. , Andrews R. H. , Ey P. L. , Albert M. J. , Grimmond T. R. , Merry D. J.
Published: June 2009

A simple technique is described for preparation ofGiardiacysts from faecal samples, the growth of trophozoites in suckling mice and the isolation of trophozoites for genetic analysis by allozyme electrophoresis. In total, 125 new isolates ofGiardiahave been collected from human and animal sources over a wide geographical area of South Australia and the Northern Territory of Australia. A number of long-established axenized isolates ofG. intestinalisbelonging to Groups I and II also adapted to grow in suckling mice. These findings indicate that suckling mice are permissive hosts for a variety of genetically dissimilar but morphologically similar organisms of theG. duodenalistype and that thisin vivotechnique may be less selective than isolation byin vitroculture. The use of suckling mice has revealed that infections can be composed of mixed genotypes and that isolation and purification techniques can be selective. Allozymic interpretation is essential to reveal the genetic complexity of such mixtures
The secreted and somatic proteinases of the bovine lungwormDictyocaulus viviparusand their inhibition by antibody from infected and vaccinated animals
Authors: Britton C. , Knox D. P. , Canto G. J. , Urquhart G.M. , Kennedy M. W.
Published: June 2009

Proteinase activities were examined in extracts and excretory–secretory (ES) products of the infective and adult stages of the cattle lungworm,Dictyocaulus viviparus. Multiple enzyme activities were identified from each source, as defined by pH optima, substrate specificities, inhibitor effects and substrate gel electrophoresis. Serine-, cysteine- and metalloproteinases were identified, secreted materials being more active against protein substrates per unit protein than were extracts, and the particular proteinases produced varied with the developmental stage of the parasite. The antigenicity of these parasite proteinases was demonstrated by the inhibition of enzymic activity with Protein G-purified serum IgG antibody from both infected and vaccinated hosts and in the retardation of enzyme migration on electrophoresis of enzyme–antibody complexes. For the adult products, this confirmed that the enzymes concerned were of parasite origin, and not host-derived. These results argue for investigation ofD. viviparusproteinases as targets for the antibody response in the limitation of parasite-mediated tissue damage and as the active principle behind the anti-D. viviparusvaccine.
Effects of testosterone onHeterakis spumosainfections in mice
Authors: Harder A. , Wunderlich F. , Marinovski P.
Published: June 2009

This study describes the effects of testosterone (Te) on the intestinal nematodeHeterakis spumosain mice. The course ofHeterakisinfections is apparently under Te-control. At high circulating Te-levels as occurring in intact males, Te-treated females, and Te-treated castrated males, the period of release ofHeterakiseggs in mouse faeces is greatly extended and the number of eggs released per unit time is markedly elevated in comparison to low Te-levels, as found in untreated females and castrated male mice. Also, the onset of the patent period occurs earlier in Te-treated mice. Testosterone also accelerates development and growth of both female and male worms ofHeterakisin mice. Thus, young adult male worms can be observed in the upper colon of Te-treated castrated male mice on day 21 post-infection (p. i.), whereas, at that time, only L4larvae are present in Te-untreated male castrates. Testosterone also favours the survival of nematodes in hosts. In untreated male castrates, the number of worms present on day 7 p.i. (L2larvae) is approximately two thirds higher than that found on day 21 p.i. However, such a reduction in the number of worms does not occur in Te-treated castrated mice during the same period of time. The early phases of the life-cycle ofHeterakis, i.e. hatching in the small intestine and final settling of L2larvae in the upper colon are independent of Te. Also, Te does not affect motility and even slightly reduces the fecundity of adult female wormsin vitro. Our data suggest that Te and/or Te-metabolites and/or Te-induced host factor(s) accelerate the development and growth ofH. spumosaand favour the survival ofHeterakisin the colon of mice.
Azygia stunkardi sp.nov. (Trematoda: Azygiidae)
Authors: Rai S. L.
Published: June 2009

The genus Azygia was erected by Looss (1899) for Fasciola tereticollis Rud. (1802) ( = Fasciola lucii Mueller, 1776) from the stomach of Esox lucius in Europe. Other species of the genus were described a few years later, namely, Azygia loossi by Marshall & Gilbert (1905) from Micropterus salmoides, Lucius lucius and Amia calva; A. volgensis by von Linstow (1907) from Lucioperca sandra; A. sebago by Ward (1910) from Salmo sebago and A. bulbosa, and A. acuminata by Goldberger (1911) from Amia calva.
Some observations on the mass mortality of the freshwater fishRutilus rutilus(L.)
Authors: Williams H. Harford
Published: June 2009

From 24 May to 4 July 1961 about 12,000 roach,Rutilus rutilus(L.), died in a lake at Brynmill Park, Swansea, South Wales. Even this high figure may be an underestimate of the actual mortality rate as it is based entirely on extractions of dead fish from the surface waters by members of the Brynmill and District Angling Club, who used landing nets from the shore only, although at fairly regular intervals. The daily counts of dead roach are represented on a histogram (Text-fig. 1). It is also of interest that in the early summer of 1961 large numbers of roach succumbed in other regions of the British Isles; about 30,000 died in the River Trent, Derbyshire, and 3000 in the lake in St James's Park, London. Newspaper reports in both localities attributed the cause to a deficiency of oxygen. For the outbreak in South Wales, however, similar reports suggested that ‘white spot disease’ caused by the ciliated protozoanIchthyophthiriuswas responsible for the mortality.
Cytotoxic activity of 13-hydroxyoctadecadienoic acid againstToxoplasma gondii
Authors: Henderson W. R. , Chi E. Y.
Published: June 2009

Recent data indicate that platelets may play an important role in the host defence againstToxoplasma gondiiinfections.T. gondii-stimulated human platelets release thromboxane A2(TXA2) and 12-hydroxyeicosatetraenoic acid (12-HETE) from arachidonic acid and 13-hydroxyoctadecadienoic acid (13-HODE) from linoleic acid (Yonget al.1991; Hendersonet al.1992). We have previously demonstrated that the eicosanoid TXA2has potent cytotoxic activity againstT. gondiitrophozoites (Yonget al.1991). In this study, we examined whether 12-HETE, 13-HODE, and linoleic acid also have toxoplasmacidal activity. 13-HODE at concentrations ≥ 10−8M rapidly induced cytotoxic changes inT. gondii. Ultrastructural changes induced by 13-HODE inT. gondiiincluded an initial leakage of cytoplasmic contents into a space between the inner and outer parasite bilayer membrane units which was followed by intracellular vacuolation and loss of cytoplasmic contents. In contrast, linoleic acid and 12-HETE lacked toxoplasmacidal activity at 10−10–10−6M concentrations. These data indicate that 13-HODE, a product of linoleic acid metabolism, has potent cytotoxic activity againstT. gondii; this toxoplasmacidal activity may be important in the inflammatory response to this pathogen.
Immune control of murine coccidiosis: CD4+and CD8+T lymphocytes contribute differentially in resistance to primary and secondary infections
Authors: Rose M. E. , Hesketh P. , Wakelin D.
Published: June 2009

The effect of treatment with monoclonal antibodies (Mabs) which deplete CD4+or CD8+T lymphocytes, on infections withEimeriaspp. was examined in NIH mice. Treatment with anti-CD4 Mab increased susceptibility to primary infections withE. vermiformisorE. pragensisand reduced the subsequent resistance of the mice to homologous challenge. Similar treatment of immune mice did not affect their resistance to re-infection but this was reduced in mice depleted of CD8+T lymphocytes. In mice immunized withE. vermiformisthe effect of CD8+-depletion was very slight, apparent only as the presence of small numbers of oocysts in the faeces of some mice; in mice immunized withE. pragensisthere was a small, though significant, increase in oocyst production, compared with controls and anti-CD4-treated groups. These results confirm the importance of mechanisms involving the function of CD4+T lymphocytes in the control of primary infections withEimeriaspp. and indicate that CD8+cells play some part in the expression of resistance to reinfection. They also show that a major part of this resistance was not affected by either of the treatments given.
Proteinases ofTrichomonas vaginalis: antibody response in patients with urogenital trichomoniasis
Authors: Bózner P. , Gombošová A. , valent M. , Demeš P. , Alderete J. F.
Published: June 2009

Immunoprecipitation combined with electrophoresis in gelatin-polyacrylamide gels was successfully used for detection of antibodies against numerous proteinases ofTrichomonas vaginalisin infected patients. The method proved to be highly specific as anti-proteinase antibodies were absent in women with negative cultivation ofT. vaginalisand no history of trichomoniasis. Sera of 71% and vaginal washes of 86% patients with trichomoniasis were positive for these antibodies. In vaginal washes, but not in sera, antibodies were partly complexed with proteinases, possibly of trichomonad origin. It was also shown that serum antibodies as well as local anti-proteinase antibodies persisted for weeks after patients had been cured.
Antibodies against somatic antigens and excreted/secreted products ofBrugia pahangiin rats with patent and non-patent infections
Authors: Fletcher C. , Wu C. C.
Published: June 2009

The humoral responses of Sprague–Dawley rats infected withBrugia pahangiwere examined for up to 6 months after infection by ELISA, immunoblotting, and IFAT. In 2 experiments, 50% and 62·5% of rats developed patent, microfilaraemic infections. Mean adult worm burdens at autopsy were approximately 2% of the inoculum, and only patent rats yielded living adult worms. IgG antibody levels against crude somatic extracts (CSE) of all parasite stages and against adult excreted/secreted (ES) products were significantly higher in patent than non-patent rats. Both patent and non-patent rats produced anti-microfilarial surface antibody, as revealed by immunofluorescence. Immunostaining of Western blots by early infection sera showed no consistent difference in recognition of infective larval (L3) antigenic components by IgG or IgM antibody between eventually-patent and eventually-non-patent rats. By 26 weeks, however, patent rats recognized more components. The data suggest that antibodies against L3, adult, and microfilarial somatic antigens, ES antigens and microfilarial surface antigens do not correlate with the subsequent development of microfilaraemia in any individual rat.
The effects of tumour necrosis factor on host—parasite relations in murineMesocestoides corti(Cestoda) infection
Authors: Jenkins P. , Spiers S. , Dixon J. B. , Carter S. D. , May S.
Published: June 2009

The regulatory role of tumour necrosis factor (TNF) was investigated in murine infection with tetrathyridia ofMesocestoides corti. Recombinant TNFα reduced macrophage larvicidal activityin vitro. M. cortiprimed mice for TNF release in response to bacterial lipopolysaccharide (LPS)in vivo. TNF activity was amplified 100-fold at 14 days post-infection (p.i.), with a further rise at day 28 p.i. Maximal inflammatory reaction was observed histologically in the liver at the height of TNF activity. Hepatic necrosis was located within inflammatory foci, but not within the vicinity of the parasite itself, suggesting that TNF may contribute to the pathogenesis of infection. Peritoneal cells from infected mice, when stimulated with tetrathyridiain vitro, showed a 4-fold increase in TNFα activity at day 14 p.i. However, when peritoneal cells were stimulated with LPSin vitro, a marked increase in TNFα secretion was observed at 2 months post-infection followed by a slow decline. It is suggested that impaired macrophage effector function, previously attributed to endogenous endotoxin, which gains access to peritoneal macrophages through an inability of the liver to detoxify endotoxin, may be mediated through TNFα.