bluuebunny/crossref_metadata_2025_split huggingface dataset:
Further observations on the relationship and distribution of Schistosoma margrebowiei and S. leiperi in central southern Africa
Authors: Pitchford R. J. , Wolstenholme B. 
Published: June 2009

ABSTRACTA further survey in East Caprivi, Chobe National Park, Okavango swamps and Kavango was undertaken in June 1976. No evidence of lechwe schistosomes was found in droppings of African buffalo (Syncerus caffer) nor baboons (Papio ursinus) living in lechwe habitats. It was thought that they were not capable of spreading or maintaining these parasites outside the confines of the known distribution of Kobus sp. The role of goats was equivocal but probably they too are poor hosts.Kavango, an endemic area of S. haematobium and S. mansoni, was thought to be free of all animal schistosomes, thus confirming the hypotheses that (1) cattle and goats are poor hosts of the lechwe schistosomes and (2)S. mattheei was blocked from entering the territory by the presence of lechwe schistosomes in the surrounding areas. Evidence of schistosomes was not found in cattle and goats at Maun for the same reasons. The prevalence of S. mansoni at Maun has increased alarmingly over the past 20 years with a simultaneous disappearance of lechwe from the area. S. margrebowiei and S. leiperi eggs were found in lechwe and tsessebe droppings some 80 km north of Maun.A high proportion of children with negative excreta from “non-endemic” areas in East Caprivi had positive CFT and/or skin tests, suggestive of exposure to lechwe schistosomes resulting in a possible immunity to S. mansoni and S. haematobium.
Immunohistological localisation of two hydatid antigens (antigen 5 and antigen B) in the cyst wall, brood capsules and protoscoleces of Echinococcus granulosus (ovine and equine) and E. multilocularis using immunoperoxidase methods
Authors: Rickard M. D. , Davies Caroline , Bout D. T. , Smyth J. D. 
Published: June 2009

ABSTRACTCyst wall, brood capsules and evaginated protoscoleces of E. granulosus (ovine and equine) and E. multilocularis were fixed in 10% formol-saline embedded in paraffin and cut at 8 μm. Specific rabbit antisera to antigen 5 and antigen B of hydatid cyst fluid were used with immunoperoxidase methods to localise the antigens in the histological sections.Antigen 5 was found in all parasites and was associated with cells of the subtegumental area of the protoscolex, the brood capsule wall and the germinal membrane. The labelled antigen appeared as distinct granules in all areas. It is suggested that antigen 5 may be synthesised in all of these sites and that a source of the antigen in cyst fluid may be the germinal and brood capsule membranes. The laminated membranes of E. granulosus (ovine and equine) were, except for the superficial layers, free from antigen 5.Antigen B was present in all parasites. It was distributed diffusely throughout the laminated membrane, germinal membrane and brood capsule wall. There were areas of densely labelled antigen B on the surface of the distal cytoplasm of the protoscolex tegument and the surface of calcareous corpuscles. The distribution of antigen B in relation to PAS positive meterial and possible complement activating substances is discussed.The laminated membrane of E. granulosus was apparently more permeable to antigen B than to antigen 5. It is suggested that differences in the diffusion of these antigens through the laminated membranes of hydatid cysts in the same or different host species may account for variable serological responses during infection.
Comparative histochemical studies of glycosidase activity in some helminths
Authors: Fujino T. , Ishii Y. 
Published: June 2009

AbstractComparative histochemical studies of glycosidase activity were carried out inClonorchis sinensis, Eurytrema pancreaticum, Fasciola hepatica, Dipylidium caninum, Hymenolepis nana, Ascaris suum, Toxocara canis, Ancylostoma caninum, Trichuris vulpis and Dirofilaria immitis. The enzymes examined were: N-Acetyl-α-Glucosaminidase (Ec 3.2.1.30), α-Glucuronidase (Ec 3.2.1.31) and α-Galactosidase (Ec 3.2.1.23). There were variations in enzyme distribution and intensity among the species and also between trematodes and nematodes; no marked positive reaction for these enzymes occurred in cestodes. In some trematodes, the caeca, especially in the brush border, and the tegument, subtegumental cells and testes, were reactive to the enzymes. In nematodes, although there was variation in reactions among species, N-acetyl-α-glucosaminidase and α-galactosidase were localized in the hypodermis and lateral cords excluding the excretory canal, and coelomocytes, intestinal epithelium and the walls of the reproductive systems.
A survey of intestinal helminths of well-cared-for dogs in Jamaica, and their potential public health significance
Authors: Robinson R. D. , Thompson D. L. , Lindo J. F. 
Published: June 2009

ABSTRACTThis study investigates the level of helminthic infestation in better-cared-for dogs in a middle-class community in suburban Kingston. A canine zoographic study was conducted, and fresh faecal deposits were collected and analysed for helminth life-cycle stages. The survey indicated that 73% (n=93) of households in the study area owned one dog or more (mean=1·4). Resident's attitudes towards canine management suggested that the dog population was, in general, restricted to the residential estate, and most owners claimed to have dewormed their dogs at least as young animals. Of 141 faecal specimens, 58% contained eggs or larvae of one or more of eight helminths: Uncinaria stenocephala (26%), Ancylostoma sp. (23%), Trichuris vulpis (9%), Toxocara canis (8%), Spirocerca lupi (6%), Strongyloides sp. (6%), Apophallus sp. (4%) and taeniids (1%). There was a high level of multiple infection in the host animals, with approximately one fifth of the infected samples containing three or more helminth types. Infection intensity was apparently low, but some dogs harboured heavy worm loads.
The effect of fatty acids on the developmental direction of Strongyloides ratti first-stage larvae
Authors: Minematsu Takeya , Mimori Tatsuyuki , Tanaka Mitsuhiro , Tada Isao 
Published: June 2009

ABSTRACTThe effect of fatty acids was studied on the developmental direction of Strongyloides ratti first-stage larvae (L1). The proportion of third-stage infective larvae increased markedly when L1 were cultured in faeces with added fatty acids such as palmitic (C16), stearic (C18), oleic (C18:1) and linoleic (C18:2) acids. Unsaturated fatty acids were more effective than saturated ones. Moreover, the proportion of infective larvae increased with quantity of linoleic acid but the triacylglycerols of any fatty acid had no effect. These results suggest that these free fatty acids cause physiological changes that determine the developmental course of L1 of S. ratti in nature.
The course of infection in rats given small primary doses of Strongyloides ratti and S. venezuelensis
Authors: Carter K. Christine , Wilson P. A. G. 
Published: June 2009

ABSTRACTDevelopment of exact doses (<100) of Strongyloides venezuelensis third-stage larvae in adult Wistar rats was insignificant (mean proportion of 0·076 of the dose at day 8, n = 16) compared with a homogonic strain of S. ratti (0·538, n = 6; 0·726, n = 6) and heterogonic S. ratti (0·681, n = 6). Newly-weaned Wistars allowed development of a mean proportion of S. venezuelensis of 0·298 (n = 4) compared with 0·013 (n = 4) of the same sample of larvae in adult hosts. Experiments with 75Se-labelled larvae established that S. venezuelensis effectively failed to migrate from skin to intestine in adult animals, while mean proportions of 0·141 (n = 5) and 0·138 (n = 4) of the label was found in the intestines of newly-weaned rats 72 h after skin application. Labelled larvae of homogonic S. ratti migrated equally well in both age groups of host (0·350 and 0·358 in 12- and 3-week-olds respectively). Adult S. venezuelensis transferred surgically to the intestines of previously uninfected full-grown Wistars survived over a 21-day period to the same extent as either strain of S. ratti. Resistance of Wistar rats to S. venezuelensis therefore appears to affect the migratory stage preferentially. S. venezuelensis developed better in mature PVG inbred rats (mean = 0·301, n = 20). Studies of S. ratti showed that infections of both strains initiated by exact (<100) doses in Wistar rats had decayed to insignificance between days 26 and 32. The rate of loss of adults of the heterogonic strain was significantly greater than that for the homogonic. The egg content of worms declined as infection progressed and rats were idiosyncratic in their influence on parasite reproduction from the earliest time of sampling (8 d). It was established that ‘autoinfection’ was an unlikely feature of the biology of homogonic S. ratti following the surgical transfer of 450 first-stage larvae to the intestines of 8 adult Wistar rats. No evidence of infection appeared in the guts of these animals 8 days post-transfer. The significance of these results in terms of the biology of Strongyloides spp. naturally occurring in the rat is discussed.
Lipid metabolism inTrichuris globulosa(Nematoda)
Authors: Sarwal Rashmi , Sanyal S. N. , Khera S. 
Published: June 2009

ABSTRACTAdult males and females ofTrichuris globulosa, an intestinal nematode parasite of goats, were studied for their lipid composition, capability of incorporation of (Na)-1-14C-acetate into different lipid classes and the activity of certain key enzymes of lipid metabolism. The parasite possesses a large variety of lipids including certain complex lipids. These are phosphatidylcholine (PC), diphosphatidylglycerol (cardiolipin), lysophosphatidylcholine (LPC), lysophosphatidylethanolamine (LPE), phosphatidylserine (PS), phosphatidylinositol (PI), plasmalogens (choline+ethanolamine), mono-, di- and triacylglycerols, free and esterified cholesterol, non-esterified fatty acids (NEFA), gangliosides, cerebrosides (glycosyl ceramide) and sulphuric acid esters of cerebrosides (sulphatides). The females contain more lipids than males, particularly the acylglycerols and phospholipids, possibly to meet the energy requirement and structural entities for the daily production of large numbers of eggs. Incorporation studies of labelled substrate, sodium-1-14C acetate demonstrate that the adult female has extremely active mechanisms for biosynthesizing these lipids. Most of the labels are found in PC, PE, SM, acylglycerols, NEFA, gangliosides, cerebrosides and sulphatides. Cholesterol, although a minor component of the parasitic lipids, incorporates large amount of label and also undergoes fast turnover. Kinetic analysis of the incorporation by measuring the rate constant (k) and half life (t½) reveals that gangliosides are the fastest biosynthesizing and turning over lipids, although they constitute only 0·1% of the total lipids. The presence of important enzymes of lipid biosynthesis, glucose-6-phosphate dehydrogenase, malate dehydrogenase and hydroxymethyl glutaryl-CoA reductase and an enzyme of lipid ester hydrolysis, triacylglycerol lipase, is also established inT. globulosa. Michaelis-Menten kinetic characteristics of the parasitic enzymes (Km, Vmax, v and the first order rate constant, k) are comparable with those of rat liver homogenates.
Muellerius capillaris in north-east Zaire: prevalence in sheep and goats and determination of intermediate hosts
Authors: Cabaret J. , Chartier C. 
Published: June 2009

ABSTRACTMuellerius capillaris was the only species of nematode recovered from the lungs of young and adult sheep and goats of north-east Zaire. The prevalences were of 19% (sheep) and 32% (goats). The slug Atoxon pallens contained larvae in natural conditions and represents a potential intermediate host. The land snails Achatinidae (Achatina stuhlmanni and Limicolaria spp.) could not be experimentally infected with M. capillaris larvae.
Effects of galactose, mannitol, glucose and α-methyl-D-glucoside on the incorporation of32P-inorganic phosphate into phospholipids inHymenolepis diminuta(Cestoda)
Authors: Ip Y. K. , Khan M. M. 
Published: June 2009

ABSTRACTIn the presence of glucose and galactose, the incorporation of radioactive inorganic phosphate (32Pi) into phosphatidylcholine ofHymenolepis diminutawas significantly lowered as compared to the control, whereas other phospholipids remained unaffected. α-methyl-D-glucoside, however, significantly lowered the amount of32Pi incorporated into phosphatidylcholine, phosphatidylinositol, phosphatidylethanolamine and phosphatidic acid. Mannitol did not have any effect on the incorporation of32Pi into the phospholipids ofH. diminuta. The effect of glucose and α-methylglucoside on phospholipid metabolism was both time and concentration dependent. The inorganic, organic, total and phosphatidylcholine-bound phosphate ofH. diminutain the presence of various substrates were not significantly different from the control values under all incubation conditions. The results indicate that the observations made in the presence of external glucose, galactose and α-methylglucoside were due to their physical interaction with the transport mechanism in the tegumental membrane ofH. diminutaand also their being subsequently metabolized in the cases of the former two hexoses.
Larval Anisakis simplex (Rudolphi, 1809, det. Krabbe, 1878) and larval Hysterothylacium sp. (Nematoda: Ascaridoidea) in euphausiids (Crustacea: Malacostraca) in the North-East Atlantic and northern North Sea
Authors: Smith John W. 
Published: June 2009

ABSTRACTOver 26000 specimens representing five euphausiid species collected, mostly in 1969, in the North-East Atlantic and northern North Sea were examined for parasites. Hysterothylacium sp. larvae were rare, occurring in only two euphausiid samples from inshore localities; the 9 larvae found (3.8 to 12.3 mm long) are described and illustrated. Infection with larval Anisakis simplex was virtually restricted to Thysanoessa spp. and appeared to be discontinuous. Infection was absent to the west of Scotland, and rare to the north of Scotland and at the Faroes. Larval A. simplex was not uncommon in offshore regions of the northern North Sea at depths between 100 and 200 m; the prevalence rate there for individual euphausiid species in individual samples was mostly 0 to 40% but an exceptionally high rate of 78.0% was recorded. Larvae in euphausiids do not become encapsulated but appear to remain active. Experimental observations on the sedimentation rate of A. simplex eggs and hatched larvae in sea water at 10°C are discussed in relation to embryonation and hatching at different temperatures, and depth of the sea. New host records are claimed for larval A. simplex in Nyctiplutnes couchii, and for larval Hysterothylacium sp. in Thysanoessa inermis. No individual euphausiid harboured more than one parasite, either larval nematode or ellobiopsid (see also SMITH, 1981). Morphological and morphometric observations on larval A. simplex from euphausiids are reported elsewhere (SMITH, 1983).
Factors influencing the establishment of Mesocestoides corti in mice following oral inoculation of tetrathyridia
Authors: White T. R. , Thompson R. C. A. , Penhale W. J. 
Published: June 2009

ABSTRACTFactors which influence the establishment of tetrathyridia of Mesocestoides corti in mice following inoculation per os were examined. Only a proportion of the tetrathyridia penetrate the gut wall and gain access to the peritoneal cavity and liver, and most of these penetrate through the wall of the small intestine. It appears that tetrathyridia must attach to the intestinal mucosa and commence penetration immediately or they pass into the large intestine and are voided. Establishment was not influenced by strain, sex or age of host. However, the temperature at which tetrathyridia were maintained before inoculation did influence their ability to penetrate the intestinal wall. Additionally it appears that tetrathyridia have to undergo a morphological change before or during, this penetration phase.
Biology of Monanema globulosa, a rodent filaria with skin-dwelling microfilariae
Authors: Bianco A. E. , Muller R. , Nelson G. S. 
Published: June 2009

ABSTRACTMonanema globulosa (Nematoda: Filarioidea) was recovered from four species of rodents in Kenya, with a prevalence of up to 94% in the striped mouse, Lemniscomys striatus. The adult worms are site-specific to the pulmonary arteries and release sheathed microfilariae that travel via the blood to the skin. Densities of microfilariea in the ears (mf/mg) were five to eight times greater than in any other region of the body and were directly proportional to the number of adult worms present. Highest concentrations of microfilariae in the skin were reached after 100 to 200 days and low numbers persisted in most animals for approximately 500 days.Third-stage larvae from ticks (Haemaphysalis leachii) injected subcutaneously into jirds migrated widely through the body during early development. Moults occurred twice, after 5 to 10 days and 25 days, and the mean prepatent period was 75 (range 69 to 88) days. A mild eosinophilia developed which peaked after 29 days. Adults in the lungs provoked widespread and intense perivascular cuffing and more localized hypertrophy and fibrosis of the intima in arterioles. Dead adults caused granulomata which obliterated smaller vessels. Microfilariae in the skin elicited no local tissue reaction, but some which invaded the eyes caused a monocyte infiltration of the cornea. It is concluded that the parasite is well adapted to its natural hosts and that it has potential as a rodent model for human onchocerciasis because of the localization of microfilariae in the skin.
Brugia pahangiin nude mice: protective immunity to infective larvae is Thy 1·2+cell dependent and cyclosporin A resistant
Authors: Vickery Ann C. , Nayar Jai K. 
Published: June 2009

ABSTRACTMechanisms of protective immunity to larvae ofBrugia pahangiwere studied in congenitally athymic nude C3H/HeN mice and their syngeneic heterozygous littermates. An average 11% if subcutaneous larval inocula was recovered from control nudes 28 days after inoculation. No worms were recovered from nude recipients of viable splenic Thy 1·2+T lymphocytes from heterozygotes which had killed a priming does ofB. pahangilarvae. Primed T lymphocytes, depleted of either Lyt 1·1+of Lyt 2·1+cells or incubated with anti-Thy 1.2 monoclonal antibody and complement, failed to protect nude mic against a larval challenge. Nor were primed B lymphocytes depleted by Thy 1·2+T cell contaminants protective. Treatment with cyclosporin A (CsA) did not increase the numbers of worms recovered from heterozygotes nor did CsA treatment of heterozygous cell donor abolish the ability of primed Thy 1·2+T lymphocytes to transfer protection to nude mice. IgG but not IgM antibody titres toB. pahangiantigens were depressed in all CsA-treated mice. CsA treatment of nude mice had no direct effect upon development ofB. pahagilarvae. These results show that ptotective immunity to larvae ofB. pahangiin mice depends upon small numbers of Thy 1·2+T cells which are CsA-resistant.
Comparative study of assays detecting circulating immune complexes and specific antibodies in patients infected with Toxocara canis
Authors: Aguila C. , Cuéllar C. , Fenoy S. , Guillén J. L. 
Published: June 2009

ABSTRACTA sandwich ELISA method using previously described E/S antigen-specific monoclonal antibodies has been developed to detect circulating immune complexes in patients infected with Toxocara canis. This technique could be used for the study of the dynamics of the parasite-host relationship, as we believe the detection of immune complexes and/or soluble antigen to be an improvement over detection of antibodies only. In this parasitosis, antibodies may be present in residual levels for prolonged periods after active infection.
Superoxide dismutase activity in nematodes
Authors: Sanchez-Moreno M. , Leon P. , Garcia-Ruiz M. A. , Monteoliva M. 
Published: June 2009

ABSTRACTThe activities of the enzymes superoxide dismutase (E.C.:1.15.1.1) and catalase (E.C: 1.11.1.6) were studied in purified extracts of four nematodes:Ascaris suum, Toxascaris leonina, Toxocara canisandT. catiadult males and females. No catalase activity was found in any of the extracts. The results reveal that the SOD activities of the four parasites presented species differences and also sexual differences within each species. Polyacrylamide gel electrophoresis pattern analysis confirmed that the mobilities, widths and band intensities varied according to the species and sex of the parasite from which the enzyme was obtained.
Chemoprophylactic studies with ivermectin against subperiodic Brugia malayi infection in the leaf monkey, Presbytis cristata
Authors: Mak J. W. , Lam P. L. W. , Noor Rain A. , Suresh K. 
Published: June 2009

ABSTRACTFour Presbytis cristata were treated with oral ivermectin at the same time as the subcutaneous inoculation of 100 infective larvae monthly for three months. Two animals given 0·2 mg/kg monthly and two others given 0·3 mg/kg monthly as well as three control animals became patent for microfilaraemia. However, only 1% of the infective dose was recovered as adult worms from animals in the higher drug dosage group compared to 8·2% and 6·2% in the lower dosage and control groups respectively.
A comparative study of the protein content of some helminths and the suitability of assay methods
Authors: Abidi S. M. A. , Nizami W. A. 
Published: June 2009

ABSTRACTThe protein content of fresh homogenates and their corresponding TCA precipitated fractions of 10 different species of helminths was estimated by the methods of Lowryet al.and Spector using the Folin phenol reagent and Coomassie brilliant blue G-250 respectively. The former method gives exaggerated values as compared to the latter method. The parasite phenols, phenolic proteins and catecholamines could be responsible for interference in the Lowry's procedure. The TCA non-precipitable moieties also give colour only with the Folin phenol assay. The pronounced intra-specific differences in the total protein content of helminths reflect their metabolic variations and adaptations. Habitat does not appear to influence the protein content of parasites, however, the effect of host variation was evident in the pouched amphistomeG. crumenifer. It is concluded that the dye binding method gives more consistent results and it can be conveniently applied to crude tissue homogenates of helminths.
Studies on the chemical nature of the cyst wall ofMicrophallus madrasensis
Authors: Ramasamy P. , Panicker S. Lekha 
Published: June 2009

ABSTRACTThe cyst wall ofMicrophallus madrasensisresisted 6 N and 11·3 N hydrochloric acids (HCL) 36 N concentrated sulphuric acid (H2S04) and 0·35 M sodium hypochlorite. It was partially dissolved in 0·6 M sodium azide and completely dissolved in 16 N nitric acid (HNO3). An HCl hydrolysate of the cyst wall contained 10 amino acids viz. alanine, leucine, aspartic acid, glutamic acid, lysine, histidine. phenylalanine. tyrosine. cystine and proline. Polyacrylamide gel electrophoresis revealed the presence of a fast moving fraction which stained with periodic acid-Schiffs (PAS) reagent and toluidine blue was noticed in tris-glycine buffer soluble and methanol water soluble substances present in the cyst wall. Triton X-100 soluble substances present in the cyst wall revealed the presence of two slow-moving fractions stained only with PAS, and also a fast-moving fraction stained only with toluidine blue. Sodium dodecyl sulphate (SDS) soluble substances in the cyst wall revealed the presence of two fast-moving fractions which stained with PAS and toluidine blue. The slow-moving fractions are protein-bound carbohydrates. The fast-moving fractions obtained after fractionation with SDS are acid mucopolysaccharides or nucleoproteins whereas the single fraction (Triton X-100 soluble substances) which stained with toluidine blue appears to be a carbohydrate-free protein. The cyst wall ofM. madrasensisalso consisted of phospholipids and neutral lipids.