bluuebunny/crossref_metadata_2025 huggingface dataset:
Acanthocheilonema viteae (Dipetalonema viteae)in mice: differences in the relative binding of microfilarial surface-specific antibody may explain the contrasting response phenotypes of BALB/c and C57BL/10
Authors: Gatrill A. J. , Kee J. , Behnke J. M. , Wakelin D.
Published: June 2009

Experiments were carried out to obtain additional data concerning the role of IgM antibodies, specific for the cuticular surface of the microfilariae (mf) ofA. viteae, in clearing microfilaraemia from high-and low-responder mice infected by transplanted adult worms. Although BALB/c mice, which sustain a chronic microfilaraemia, produced IgM mf surface-specific antibodies, the binding to target mf was weak when compared to that of antibodies from the serum of the resistant C57BL/10 mice. Furthermore, antibodies from BALB/c mice were not as efficient as those from C57BL/10 mice in promoting the adherence of immune or control leukocytes to mfin vitro. Evidence is provided to show that mf shed surface bound antibody. Although the results do not establish conclusively the mechanism underlying the contrasting response phenotypes of C57BL/10 and BALB/c mice, they provide support for the involvement of antibody in controlling microfilaraemia and suggest that quantitative and qualitative differences in the amount and affinity of IgM antibody specific for the mf surface, together with the natural tendency of the mf to shed surface bound antibody at 37°C. may combine to allow the former strain to clear microfilaraemia efficiently whilst the latter sustains a chronic infection.
Studies on the cryopreservation of eggs of Angiostrongylus cantonensis
Authors: Uga Shoji , Araki Kazuyoshi , Matsumura Takeo , Iwamura Noboru
Published: June 2009

The possibility of cryopreserving the eggs of Angiostrongylus cantonensis collected from the uterus of female worms was investigated. Eggs were cultured in NCTC 109 medium containing 50% rat serum, and various growth stages, from one-cell eggs to embryonated eggs, were used in this study.

As a cryoprotective agent, dimethylsulphoxide (Me2SO) was added to the medium at a final concentration of 1 M. Eggs suspended in 0·2 ml of the medium at 37°C were cooled to 0°C at a rate of l°C min−1, then an equal volume of 2M-Me2SO solution was added. After equilibration for 15min, the freezing procedures were started. In the freezing procedures, the effectiveness of (i) a seeding process, (ii) different cooling and warming rates and (iii) the relationship between the growth stages of the eggs and their tolerance to freezing at −20°C were investigated.

It was found the highest level of survival could be obtained with 32-cell eggs cooled at a rate of 0·3° C min−1 or more slowly with seeding at −4°C and warming at a rate of 5°C min−1. Survival was influenced more by cooling rate than by warming rate.

Using these optimum conditions, the survival of eggs was then investigated following cooling to various temperatures. While more than 50% of eggs were found to survive cooling to −30–C, extremely low survival was noted from lower temperatures.
Cryopreservation of Dirofilaria immitis microfilariae and third-stage larvae
Authors: Lok J. B. , Mika-Grieve M. , Grieve R. B.
Published: June 2009

Microfilariae of Dirofilaria immitis retained their infectivity for susceptible mosquitoes after cooling to −196°C in the presence of 5% dimethylsulphoxide (Me2SO) using a two-step cooling sequence. Motility and in vitro development of cryopreserved microfilariae also compared favourably with unfrozen controls. Third-stage larvae frozen by the same cooling sequence in the presence of either 5% Me2SO or 16% hydroxyethyl starch were motile upon thawing. Thawed larvae completed the third- to fourth-stage moult in vitro at a frequency approximately 5 to 10% of that seen in unfrozen controls.
Eosinophilia inAscaris suum-reinfected mice
Authors: Sugane Kazuo
Published: June 2009

The secondary response of eosinophilia has been studied in mice infected withA. suum. In mice infected orally with 1000A. suumeggs, larvae disappeared from the body within two weeks after infection. The number of peripheral blood eosinophils decreased to the pre-infection level within eight weeks. A typical secondary response of IgG antibody production to egg antigen was found after reinfection with 1000 eggs. The number of peripheral blood eosinophils increased more rapidly after reinfection than after the primary infection. However, the peak number of eosinophils after reinfection was similar to that after primary infection, and the long-lasting characteristics of eosinophilia after reinfection did not differ from those after primary infection. These results suggest that the secondary response of eosinophilia is characterized by a rapid increase in the number of eosinophils inA. suum-reinfected mice.
Observations on the infectivity and fecundity of Schistosoma curassoni from Senegal in albino mice
Authors: Vercruysse J. , Southgate V. R. , Rollinson D. , Hilderson H. M.
Published: June 2009

An average of 11% of adult Schistosoma curassoni were recovered from 200 albino mice which had been infected subcutaneously with 150–250 cercariae. Worms were primarily found in the portal veins. The average number of intrauterine eggs per female during the first 100 days p.i. was 13 and the average number of eggs produced per female worm was 103 per day for the first 60 days post oviposition. The majority of eggs were recovered from the liver (98·3%). The oograms were determined until day 95 p.i. For screening of antischistosomal drugs it is recommended not to use infections older than 60 d.p.i.
Scanning electron microscope studies of miracidia suggest introgressive hybridization between Schistosoma haematobium and S. haematobium x S. mattheei in the Eastern Transvaal
Authors: Kruger F. J. , Hamilton-Attwell V. L.
Published: June 2009

Schistosoma haematobium miracidia were collected from a locality with a high prevalence of human infection with the animal parasite, S. mattheei, which hybridizes with S. haematobium, and from 2 localities with negligible infection rates. The terebratoria of the miracidia from these localities were compared with each other, with laboratory maintained S. haematobium and with four populations of S. mattheei by means of scanning electron microscopy. It was found that the terebratorial membrane of certain of the S. haematobium miracidia from the locality with a high S. mattheei prevalence in humans, resembled the more intricate membrane of S. mattheei. This suggests introgressive hybridization between S. haematobium and S. haematobium x S. mattheei.
Abnormal patterns of embryogenesis inDirofilaria immitistreated with ivermectin
Authors: Lok J. B. , Harpaz T. , Knight D. H.
Published: June 2009

The percentage composition and spatial distribution of embryogenic stages in the uteri of femaleDirofilaria immitiswere examined at various times after treatment with a microfilaricidal dose of ivermectin and compared to nontreated parasites. Worms sampled 42 days post-treatment (PT) exhibited an increased proportion of stretched microfilariae in the distal portion of the uterus. A decreased proportion of developed embryos was noted in the mid body region of worms sampled 42 days PT, and these forms were completely absent from the proximal area of the uterus. Relative numbers and spatial distribution of other stages remained virtually identical to controls. Radical changes in the composition and spatial distribution of embryogenic forms were noted in the uteri of a single worm sampled 80 days PT. Unlike nontreated parasites and worms sampled 42 days PT, stretched crofilariae constituted the predominant form in the distal uterus of this worm, and these stages were found in decreasing numbers throughout the proximal segments. Also, the intermediate embryogenic stages were either rare or absent.
The tegument in Hemiuridae (Digenea: Hemiuroidea): structure and function in the adult
Authors: Matthews B. F. , Matthews R. A.
Published: June 2009

The teleost stomach, as a site of strong acid proteolytic digestion at pH 1–4, is a hostile environment rarely chosen as a habitat by parasites. Several Hemiuroidea have nevertheless invaded this niche, notably the Hemiuridae, a family in which the body is characterized by a retractile “tail”, or ecsoma. The structure and function of the latter has been studied in three hemiurid species, namely Hemiurus communis, Lecithochirium rufoviride and L. fusiforme, using ultrastructural, histochemical and autoradiographic techniques. Results indicate a clear demarcation between the function of the tegument covering the ecsoma and that of the rest of the body, or soma. No mitochondria have been observed in the ecsomal tegument, and intense acid phosphatase activity was detected in association with its outer plasma membrane. Uptake of 3H-tyrosine occurred within the excretory vesicle, which may serve for transport of nutrients forwards into the soma. In contrast, the thickened, dense somal tegument, with few mitochondria largely confined to ridges or plications in H. communis, showed neither phosphatase activity nor uptake of tyrosine. Glucose uptake was not detected in any part of the body. That the somal tegument serves not for absorption but for protection against both physico-chemical conditions and mechanical damage by prey entering the host's stomach is discussed.
Echinococcus granulosus: development of resistance to albendazole in an animal model
Authors: Morris D. L. , Taylor D. H.
Published: June 2009

Gerbils with well developed peritoneal cysts of Echinococcus granulosus were randomized to albendazole 50 mg/kg/day or untreated control. Treated animals had less disease at post mortem after 3 months of treatment. Cysts were then taken from both albendazole-treated and control animals and cultured in vitro either with or without albendazole sulphoxide (Alb Sx) 500 μg/L for 14 days. Viability of cysts was then established by implantation of whole cysts into gerbils. Whilst naive cysts were affected by Alb Sx (only 2 cysts developed/gerbil) cysts from animals treated with albendazole were not sensitive to further therapy (6.4 cysts/gerbil).
On the morphology and life-history of Hemiurus luehei Odhner, 1905 (Digenea: Hemiuridae)
Authors: Køie Marianne
Published: June 2009

Previously undescribed cystophorous cercariae which develop in sporocyst germinal sacs in the tectibranch opisthobranch Philine denticulata (Adams) are shown to be cercariae of Hemiurus luehei Odhner, 1905 (Hemiuridae), a common stomach parasite of clupeid and salmonid fishes off the Atlantic coast of Europe, in the Baltic and the Mediterranean Sea. The free-swimming cercariae are seized by calanoid copepods. Temora longicornis (Müller) and Acartia tonsa Dana acted as suitable experimental intermediate hosts. Pressure by the copepod mouth appendages causes delivery tube eversion and the injection of the cercarcial body into the haemocoel. Sagitta sp. was found naturally infected with a metacercaria of H. luehei. The cystophorous cercaria and metacercaria are described using light and scanning electron microscopy. Adults from herring were examined under the stereoscan electron microscope.
The pig as an intermediate host for Taiwan Taenia infection
Authors: Fan P. C. , Chung W. C. , Lin C. Y. , Wu C. C.
Published: June 2009

Eggs (1000–100 000/animal) of Taiwan Taenia were inoculated per os into 14 Small-Ear-Miniature (SEM), 19 Landrace-Small-Ear-Miniature (L-SEM), and 5 Duroc-Yorkshire-Landrace (DYL) pigs. These animals were sacrificed 7–107 days after infection. Thirty-four pigs were found to be infected with Taiwan Taenia cysticerci and the infection rates of SEM, L-SEM, and DYL were 86%, 89% and 100% respectively. The cysticerci recovery rates of SEM, L-SEM and DYL pigs were 27·2%, 1·7% and 0·27% respectively. Cysticerci were recovered only from the livers and none were found in muscles, viscera or other parts of the carcasses. More cysticerci were located in the liver parenchyma (71%) than on the liver surface (29%). Taiwan Taenia cysticerci were smaller than those of classical T. saginata or T. solium. Moreover, Taiwan Taenia cysticerci had 2 rows of rudimentary hooklets on the scolex. The results of this study indicate that young pigs are good intermediate hosts for Taiwan Taenia and that the SEM pig is a satisfactory host for experimental studies with this tapeworm. These results were similar to other studies with different geographic strains of the T. saginata-like tapeworm in the Far East. These strains appear to be the same and possibly a new species.
Comparative susceptibility to anthelmintics ofBrugia pahangiin jirds infected by different methods
Authors: Surin Johari , Denham D. A.
Published: June 2009

It is possible to infect jirds withBrugia pahangiby three methods. Infective larvae (L3) can be injected either intraperitoneally (ip), when adults develop in the peritoneal cavity, or sub-cutaneously (sc), when they develop in the lymphatics or the heart and blood vessels associated with the lungs. Alternatively adult worms which have been grown in the peritoneal cavities of jirds can be implanted into the peritoneal cavities of other jirds. This latter system has been widely used for screening for new filaricides. We have compared the activity of 9 macrofilaricidal compounds against these 3 types of infection. Mebendazole and albendazole were more active against implanted adults than against L3 induced adults in the peritoneal cavity. Oxibendazole, flubendazole, CGP24588A and oxfendazole were equally active against both types of worm. CGP20376, Mel Ga and Mel Ni were more active against adult worms derived from inoculated L3 than implanted worms. When comparing intra-lymphatic and ip adults (both derived from L3 infections and in the same jirds) albendazole and CGP20376 were active at the same levels against both types of infection. Mebendazole, flubendazole, oxfendazole, CGP24588A, Mel Ga and Mel Ni were more active against ip adults than intra-lymphatic adults. No drug was more active against intra-lymphatic adults than against adults.
Scanning electron microscopy of the cuticular armature of the nematode Gnathostoma spinigerum Owen, 1836 from cats in Laos
Authors: Scholz Tomáš , Ditrich Oleg
Published: June 2009

The body surface of an immature female Gnathostoma spinigerum found for the first time in the definitive host (Felis catus f. domestica) in Laos was studied using a scanning electron microscope. All types of cuticular spines, which are one of the most important features for species identification of gnathostomid nematodes, together with their spatial arrangement, are described and figured.
Evaluation of chemotherapy in experimental toxocarosis by determination of specific immune complexes
Authors: Cuellar C. , Fenoy S. , Aguila C. , Guillen J. L.
Published: June 2009

Parasitism by the larval phase ofToxocara canisis a chronic process in which the larvae survive in the tissues, resulting in the constant stimulation of the immune system. As a result, the detection of specific antibodies may not reflect the active state of the parasite. We have studied the dynamics of the production of specific immune complexes by ELISA with the monoclonal antibody TC-1 in rabbits inoculated with single and multiple doses ofT. caniseggs. We also compared this with the production of specific antibodies and their possible modification after treatment with mebendazole. The specific antibodies against excretory-secretory antigen were detected with peaks at 10 and 12 weeks depending on the dose and remained positive during the entire experiment (62 weeks). Treatment caused an increase in the level of detectable antibodies dropping to similar levels to the controls. Specific immune complexes were detected only in multiple doses, and were then positive during the entire experiment. From the beginning of treatment the values of immune complexes fell quickly, remaining at undetectable levels during the rest of the experiment. For this reason the detection of specific immune complexes is a valid technique for monitoring the efficiency of treatment.
Analysis of polyunsaturated fatty acid composition ofStrongyloides rattiin relation to development
Authors: Minematsu Takeya , Yamazaki Seietsu , Uji Yoshinori , Okabe Hiroaki , Korenaga Masataka , Tada Isao
Published: June 2009

The effect of linolenic acid (C18:3ω3) on the development ofStrongyloides rattifirst-stage larvae (L1) in culture was studied. The fatty acid composition ofS. rattifree-living generations was analyzed by gas chromatography. L1had abundant linoleic acid (C18:2ω6) but its proportion decreased with development. On the contrary, eicosapentaenoic acid (C20:5ω3) and C20:4ω3 were prominent in the filariform larva (L3). Because C20:5ω3 is generally synthesized from C18:3ω3 via C20:4ω3, the high ratio of C20:5ω3/C18:3ω3 of L3in all the free-living generations suggested that polyunsaturated fatty acid metabolism, particularly the ω-3 series, and eicosanoids produced had important roles in the development ofS. rattiL1.
Immunoblot analysis of serum IgG, IgA and IgE responses against larval excretory-secretory antigens of Anisakis simplex in patients with gastric anisakiasis
Authors: Akao Nobuaki , Ohyama Taka-Aki , Kondo Kaoru
Published: June 2009

To increase our understanding of the immune response to Anisakis infection, antigen specific IgG, IgA and IgE responses were identified using an immunoblot technique after polyacrylamide gel electrophoresis of excretory-secretory products from the larval stage of Anisakis simplex. Nine sera were drawn from proven cases of gastric anisakiasis within 3 days after symptoms had developed. The molecular weight of the major antigenic bands were distributed between 50 kDa and 120 kDa of the antigens. In nine cases of gastric anisakiasis, three of them were positive for IgG response, five for IgE, and six for IgA, respectively. None of control sera recognized the antigenic bands in IgA and IgE responses. In contrast, two controls had IgG antibodies against 1–2 proteins in the 65–95 kDa region. The antigenicity of the excretory–secretory products was lost following treatment by 0·2% trypsin, but not by 0·2 M periodic acid. Based on the results of reactivity to lectins, antigenic bands of the ES products possessed mucin type glycoconjugate residues in their protein portion. This indicates that the humoral responses of IgA and IgE antibodies to the larval ES antigens are a more reliable index of infection than that of the IgG response.
Prevalence of Cooperia punctata, C. pectinata and C. oncophora infections in dairy calves in Brazil
Authors: Guimaraes M. P. , Costa H. M. A. , Lima W. S.
Published: June 2009

Cooperia is the most prevalent helminth parasitizing calves in Brazil. Three species of this genus occur most often: C. punctata, C. pectinata and C. oncophora. Six calves from dairy farms in the south of the State of Minas Gerais aged six to 15 months were killed and necropsied each month over a period of two years. The Cooperia species were identified, counted, and the numbers related to the calves' age. The worm burdens due to the three species of Cooperia were statistically different. C. punctata was the most prevalent species and had a positive correlation with the age of the calves; C. pectinata appeared with lower intensity but was always present, and C. oncophora was not found in calves older than 11 months. These results show the existence of different degrees of resistance to Cooperia species among calves as the three species did not behave similarly. It seems to be an acquired resistance. C. punctata appears to be less immunogenic than C. pectinata and C. oncophora. As C. punctata and C. pectinata are more pathogenic than C. oncophora, it seems that this pathogenicity can be related to immunogenic aspects associated with the species.
Do all human urinary infections with Schistosoma mattheei Represent hybridization between S. haematobium and S. mattheei?
Authors: Kruger F. J. , Evans A. C.
Published: June 2009

Enzyme electrophoresis indicated that all Schistosoma mattheei eggs passed in the urine of humans derive from S. mattheei females in copula with S. haematobium males. It appears that S. mattheei males do not reach sexual maturity in man; however, S. haematobium×S. mattheei males possibly do.
Frequency and possible consequences of hybridization between Schistosoma haematobium and S. mattheei in the Eastern Transvaal Lowveld
Authors: Kruger F. J.
Published: June 2009

A survey was conducted at a locality in the Eastern Transvaal Lowveld where the prevalence of human infection with the bovine parasite, Schistosoma mattheei, is relatively high. It was found that, when compared to the number of S. haematobium eggs released into the environment, the number of S. mattheei eggs, with enclosed hybrid miracidia, is small. The consequences of backcrossing between the hybrids and S. haematobium was considered; a mathematical model indicated that a high percentage of the S. haematobium population should contain a small proportion of S. mattheei genes. The results indicate that it is highly unlikely that the two species will evolve into a single species, neither does it seem that the virulence of the parental species will be influenced.
An experimental in vitro model for evaluating drugs against protoscoleces of Echinococcus granulosus
Authors: Lorenzini Rodolfo , Ruggieri Anna
Published: June 2009

Pharmacological studies carried out on protoscoleces in vitro to standardize conditions that would permit a preliminary estimate of the efficacy of drugs with potential activity against Echinococcus granulosus are reported. Media such as PBS and Hanks solution, maintenance temperature, different pH values and concentrations of various solvents have been tested to check the effects on protoscolex survival in tubes in vitro. Mebendazole has been used as the pharmacological standard reference. Changes in the viability of protoscoleces have been used to demonstrate pharmacological activity. Best conditions were obtained employing Hanks solution and propylene glycol at low concentrations. Mebendazole was not completely effective at the concentrations achievable in human therapy. Linear, reproducible results demonstrated that Hanks solution provides an ideal medium for pharmacological studies. Among tested solvents, propylene glycol and dimethyl sulphoxide showed no lethal activity at low concentrations. At concentrations similar to those normally obtained in human sera, mebendazole, as in vivo, demonstrated only partial lethality for protoscoleces. The present study represents a new experimental approach to chemotherapy of hydatid disease.
Trichinella spiralis: specificity of ES antigens from pre-encysted larvae
Authors: Ko R. C. , Wong T. P.
Published: June 2009

Excretory/secretory (ES) antigens were obtained by culturing pre-encystedTrichinella spiralislarvae which were recovered from muscles of experimentally infected mice 14–15 days postinfection. Analyses of these antigens (PEL ES) with immunoblotting, SDS-PAGE and Triple Antibody ELISA showed that they yielded a low sensitivity and specificity when tested antisera against the common nematodes of Chinese pigs. As compared to ES antigens from encysted larvae. PEL ES also contained more low molecular mass proteins.
Biological control ofOstertagia ostertagiby feeding selected nematode-trapping fungi to calves
Authors: Grønvold J. , Wolstrup J. , Larsen M. , Henriksen S. A. , Nansen P.
Published: June 2009

Three nematode-trapping fungi, oneArthrobotrys oligosporaand twoDuddingtonia flagransisolates, were fed toOstertagia ostertagi-infected calves to test their ability to destroy larvae of this parasite in faeces and consequently to reduce the transmission of infective larvae to herbage. The fungi had previously been selected for their capability to pass the alimentary tract of cattle without losing growth and nematode-trapping potentials. Dung was collected from three calves each fed one of the three fungi and placed as 1-kg cow pats on a parasite-free grass plot together with control cow pats from a calf that was not given fungi. The cow pats contained comparable concentrations of parasite eggs. The twoD. flagransisolates were highly effective in that they reduced herbage larval infectivity by 74–85%. In contrast,A. oligosporadid not show any effect in the present experiment. Field experiments will demonstrate ifD. flagransrepresents a potential organism for biological control of bovine gastrointestinal nematodes under practical agricultural management conditions.
The antibody response toDracunculus medinensisin an endemic human population of northern Ghana
Authors: Bloch P. , Simonsen P. E. , Vennervald B. J.
Published: June 2009

The serum antibody response (total, and isotypes IgG1, IgG4, IgM, IgA and IgE) to Guinea worm infection was examined in humans from a highly endemic area of northern Ghana by ELISA and SDSPAGE/Western blot techniques using an adultD. medinensisantigen. Sera were obtained early and late in the peak transmission period, from persons with patent and postpatent infections, as well as from persons from the same endemic area who claimed never to have had Guinea worm infection. To observe for potential cross-reactions in the tests, sera were also obtained from areas with no transmission of Guinea worm from patients with hookworm.O. volvulusandW. bancroftiinfections, and from non-infected controls. Sera from persons living in the Guinea worm endemic area reacted extensively with Guinea worm antigen in both tests, and large numbers of bands were produced in the Western blots (up to 35 identified for some sera). For most antibody isotypes, the ELISA absorbance values obtained with sera from the same individuals varied between the two transmission seasons, with the highest titres present towards the end of the peak transmission period. The mean antibody titres for persons in the patent and postpatent infection categories were not significantly different when sera were obtained at the same season of the year. Persons from the endemic area, who claimed never to experience patent infections, also had antibodies to Guinea worm, although at significantly lower mean levels than for the patent and postpatent categories. The highest specificity in the ELISA and the most homogenous Western blots were obtained when detecting for antibodies of the IgG4isotype.
Comparative study of two methods for the diagnosis of Enterobius vermicularis in the appendix
Authors: Dalimi Abdulhossein , Khoshzaban Faryba
Published: June 2009

A total of 1590 human appendices were collected and examined histologically for evidence of pinworm infection. The incidence of infection in appendices was 2·39%. In examining 100 appendices by both the histological and the parasitological methods, 3 and 7 samples respectively were seen to be infected by pinworm.
Onchocerciasis in British cattle: a study of the transmission ofOnchocercasp. in North Wales
Authors: McCall P.J. , Trees A. J.
Published: June 2009

The transmission of bovineOnchocercaspp. in Britain was investigated by studying the Ceratopogonidae and Simuliidae which attacked bait cattle between April and October at two sites in North Wales, where eitherOnchocerca lienalisandO. gutturosa(Cynwyd), orO. lienalisalone (Pentrefoelas) occurred. Based on the relative abundance of each species, their seasonal variation in abundance and preferential feeding sites on cattle, the presence ofOnchocercasp. infective larvae and the development of patent infections in bait cattle, vectors were identified asSimulium ornatums.1. at Pentrefoelas andS. reptansat Cynwyd (0·5% and 1·5% of parous flies infective, respectively). There was no significant difference between the lengths of the infective larvae from vectors at either site (Pentrefoelas: mean = 543·5 μm, SD = 29·45; Cynwyd: mean = 550·86 μm, SD = 35·26; p > 0·1), which were consistent with descriptions ofO. lienalis. The identity of a vector forO. gutturosawas not determined and the role of certain candidates is discussed. In this respect, the absence ofCulicoides nubeculosuswas notable. Transmission ofOnchocercasp. was limited to a short period of about 8 weeks, by a combination of vector abundance and parasite uptake from dermal skin layers, and a mean daily temperature requirement of 15°C or more for complete parasite development in the vector. The effect of this temperature restriction in relation to the geographical distribution of the two species is discussed.
Antagonistic effect of predacious Arthrobotrys fungi on infective Haemonchus placei larvae
Authors: Araújo J. V. , Santos M. A. , Ferraz S. , Maia A. S.
Published: June 2009

Laboratory experiments were performed to investigate the ability of isolates from the predacious fungus species Arthrobotrys conoides (one isolate) and A. robusta (four isolates) to trap and kill infective Haemonchus placei larvae. Three groups for each isolate were formed: group 1, fungi and infective larvae; group 2, fungi; group 3, infective larvae. There were statistically significant differences (P<0.05) between the antagonistic effects of three isolates of A. robusta, but there was no such difference between the isolate of A. conoides and isolates of A. robusta. This result indicates that there can be a variation in the predatory capacity of different isolates within a single fungus species. After 20 days of assay, there was greater recuperation of infective H. placei larvae in group 3 compared to group 1.
Vaccination with hatched but non-activated, non-viable oncospheres of Taenia taeniaeformis in rats
Authors: Ito A. , Hashimoto A.
Published: June 2009

The usefulness of hatched but non-activated oncospheres as a candidate vaccine was evaluated using a Taenia taeniaeformis/rat system, since preparation of these oncospheres in vitro is known to be very simple. The findings were: (1) rats vaccinated with non-viable oncospheres became completely resistant to challenge infection; (2) intra-venous injection was the most effective to induce complete resistance; (3) a single oncosphere was sufficient to induce complete resistance in infected rats, whereas approximately 50 and 500 non-viable oncospheres were required to evoke strong and complete resistance, respectively, in vaccinated rats. The usefulness of non-viable oncospheres without adjuvant is discussed.
Water sources and other determinants of dracunculiasis in the Northern Region of Ghana
Authors: Tayeh A. , Cairncross S. , Maude G. H.
Published: June 2009

This paper describes a study carried out in a rural area of Ghana on the drinking water sources and other determinants of dracunculiasis (guinea worm disease). The results confirm the association between water source choice and the prevalence of the disease. A logistic regression model was used to show the combined effect of several behavioural, biological, and environmental risk factors. The important behavioural factors were related to the head of household, fetching of water, travelling, and farming. Age was found to be an important biological risk factor for dracunculiasis, but the greatest relative risk applied to those who had suffered from guinea worm disease in the previous year. Although males were significantly more infected than females when analysing the raw data, sex did not prove to be a significant risk factor in this model. Village of residence was an important environmental risk factor for dracunculiasis. Factors related to socio-economic status were not associated with the risk of infection. The paper concludes by presenting the policy implications of the study findings.
The effect of levamisole on acetylcholinesterase secretion by male and female Heligmosomoides polygyrus during ageing
Authors: Mallet S. , Kerboeuf D.
Published: June 2009

The inhibition of acetylcholinesterase secretion by male and female Heligmosomoides polygyrus was tested on worms taken from experimentally infected mice and maintained for 3 days in vitro in levamisole. The dose inhibiting 50% of enzyme secretion (ID 50) of male worms was twice the ID 50 for female worms. A similar difference was observed in vivo between the dose of levamisole removing 50% (LD 50) of male and female worms from the mouse. Acetylcholinesterase secretion by worms and ID 50 were tested in vitro at 3-weekly intervals from 3 to 21 weeks post infection (WPI). Acetylcholinesterase secretion was always significantly higher for male than for female worms. A decrease of ID 50, correlated with the age of the worms was observed: from 1·5 to 0·5 μg/ml for males and from 0·7 to 0·1 μg/ml for females. These results were confirmed in vivo by a higher efficacy of the anthelminthic at 21 than at 4 WPI.
The miracidium ofTransversotrema patialense(Soparkar, 1924)
Authors: Madhavi R. , Jhansilakshmibai K.
Published: June 2009

The miracidium ofTransversotrema patialense(Digenea: Transversotrematidae) has 21 epidermal cells arranged in four tiers with an epidermal formula of 6, 9, 4, 2. The penetration gland is large, conspicuous, contains a posterior globular part with 6 prominent nuclei and opens out through 6 pores arranged in two lateral groups at the tip of the apical papilla. The miracidium lacks lateral papillae, possesses a well developed subepithelium, a pair of flame cells and a germ ball.
Occurrence of Angiostrongylus vasorum in the lungs of the Brazilian fox Dusicyon vetulus
Authors: Lima W.S. , Guimaraes M.P. , Lemos I.S.
Published: June 2009

Angiostrongylus vasorum infection was detected for the first time in eight foxes (Dusicyon vetulus) captured in the south of the State of Minas Gerais, Brazil. Two crossbred dogs were successfully infected orally with larvae from the foxes' faeces.
Encapsulated egg deposition pattern of Schistosoma japonicum in the peritoneal cavity of mice
Authors: Fan P.C. , Lin L.L.
Published: June 2009

Thirty-four albino mice were each exposed to 20 cercariae of Schistosoma japonicum by the intraperitoneal or percutaneous route and killed after 60–127 days. The peritoneal cavity of each mouse was flushed and worms in the portal vein system were perfused with citrated saline. After sedimentation, washings were examined microscopically. Mature worms were only found in the portal vein system. The worm recovery rate was much higher by percutaneous infection (61.2%) than by intraperitoneal (37.1%). The encapsulated egg granulomas were observed either in the peritoneal cavity or on the intestinal wall; the mean number of encapsulated egg granulomas was also higher in the former (1.6) than in the latter (0.6). The average number of eggs per granuloma was very similar by both routes (10.7 and 11.4). The mean size of encapsulated egg granulomas (529 μm) was increased correspondingly with the number of eggs (range 181–985 μm). The percentage of viable eggs within the granulomas in the peritoneal cavity (77%) was much higher than those on the intestinal wall (18%). Encapsulated egg granulomas were usually ovoid although some had an irregular shape.
Interspecific stimulation of parthenogenesis in Schistosoma intercalatum and S. mansoni
Authors: Tchuenté L.A. Tchuem , Imbert-Establet D. , Southgate V.R. , Jourdane J.
Published: June 2009

Experimental studies of mating behaviour of Schistosoma intercalatum and Schistosoma mansoni in mixed infections in mice showed that in simultaneous infections, without the possibility of choice of mate, heterologous pairing occurs readily. The paired females reach sexual maturity, are inseminated and lay parthenogenetic eggs. Miracidia originating from the S. mansoni male × S. intercalatum female are non infective to either Biomphalaria glabrata or Bulinus forskalii, whereas those from the reverse cross show a very low infectivity to only B. glabrata. The resulting haploid male cercariae also show a very low infectivity to mice (1.1%) and consequently only a very small number of adult worms develop. It appears from this study, on chromosomal and electrophoretic evidence, that generative (haploid) parthenogenesis occurs in S. mansoni females paired with S. intercalatum males.
Isolation of microfilariae and eggs of Setaria digitata
Authors: Das D. , Das M.K.
Published: June 2009

A simple procedure of gel-filtration was used to purify microfilariae of the cattle parasite, Setaria digitata from its eggs. The eggs of S. digitata were also isolated from the female worms by picking out the uterine canal. Gel-filtration gave a recovery of 70% for microfilariae.
The prevalence of Taenia solium metacestodes in pigs in northern Tanzania
Authors: Boa M.E. , Bøgh H.O. , Kassuku A.A. , Nansen P.
Published: June 2009

Eighty three carcasses of pigs were examined at three abattoirs in Moshi, Arusha and Mbulu in northern Tanzania. Taenia solium metacestodes were found in all the three abattoirs with an overall prevalence of 13.3%. During routine meat inspection in Kiboroloni, Moshi 6.2–6.9% of the pigs were found to harbour T. solium metacestodes. The mean number of hooks on the protoscolices was 27 and the length of the small hooks varied from 105 mm to 130 μm while that of the larger hooks varied from 168 mm to 174 mm confirming that the cysts were metacestodes of T. solium. Although cystlike lesions were recovered from livers of both pigs and cattle, no booklets of sizes in the range of 5–37mm were found indicating that no Taiwan Taenia metacestodes were recovered during carcass examination.
Schistosoma haematobiumin the baboon (Papio anubis): assessment of protection levels against either a single mass challenge or repeated trickle challenges after vaccination with irradiated schistosomula
Authors: Reid G.D.F. , Sturrock R.F. , Harrison R.A. , Tarara R.P.
Published: June 2009

Baboons vaccinated intramuscularly with three times 9000 20 krad irradiatedSchistosoma haematobiumschistosomula at monthly intervals were exposed percutaneously to either a single mass challenge of 3000 (VMC) or ten, weekly trickle challenges of 300 (VTC) normalS. haematobiumcercariae. Unvaccinated mass (MCC) or trickle (TCC) challenge controls were exposed simultaneously. Faecal and urine egg production was delayed in the vaccinated groups which also had reduced adult, particularly female, worm recoveries. Total faecal, urine and tissue eggs were lower in the vaccinated groups, as also were the size of granulomata and the gross pathology and severity of inflammatory responses in the bladder and ureters, except for an increased proportion of tissue eggs in the livers of vaccinated animals. Differences in pathology between groups were less marked in the other organs. Most indices were reduced in the trickle versus the mass challenge control groups. Some of these trends were statistically significant, mostly in the trickle vaccination group (VTC), but others were not. Compared with the appropriate unvaccinated controls, the percentage reduction for the trickle challenge (VTC) group (73%) was three times greater than that of the mass challenge (VMC) group (23%). Overall, the protective effect of vaccination was more clearly demonstrated in the trickle than in the mass challenge groups. This conclusion is based on a single experiment. Nevertheless, because trickle infections probably approximate more closely to what humans receive naturally, it is recommended that they should be used for future testing of all potential vaccines in baboons.
The effects of freezing on the viability of Toxocara canis and T. catiembryonated eggs
Authors: O'Lorcain P.
Published: June 2009

Suspensions of embryonated (L2) Toxocara canis and T. cati eggs were maintained under freezing conditions in order to study the impact on their long term viability The eggs had been removed from the uteri of adult Toxocara spp. worms and the suspended in a 0.4% formalin solution before being frozen in 20 ml plastic tubes in the freezer compartment of a domestic refrigerator. Assessment of embryonated egg viability over a period of 34 days was conducted by microscopic examination under a high light intensity Embryonated T. cati eggs were found to exhibit a greater resistance to freezing than those of T. canis. A difference in the size, design of the egg shell or the metabolism of the larval form may have accounted for the observed differences in the percentage viabilities over time between the two species of Toxocara.
Effects of free and liposomized praziquantel on worm burden and antibody response in mice infected withMesocestoides cortitetrathyridia
Authors: Hrčkova G. , Velebny S.
Published: June 2009

The parasite burden in the liver and peritoneal cavity and antibody levels directed to whole worm extract, have been monitored in serum from ICR-strain mice, infected orally with 55 tetrathyridia ofMesocestoides corti(Cestoda, Cyclophyllidea). The subcurative doses (3x or 6x) of praziquantel (PZQ) (10 mg.kg−1body weight) were administered to mice from day 14 post infection (p.i.) in two drug formulations: as PZQ suspended in Dorfman vehicle, or as PZQ incorporated in liposomes (lip.PZQ). The appearance of antibodies was time-dependent and correlated with the rate of reduction in numbers of tetrathyridia. PZQ in three and six doses caused the highest fall of parasite numbers in the liver on day 1 post therapy (p.t.). In the peritoneal cavity, a similar reduction in worm burden occurred but only after six doses of the drug. The worm count in the peritoneal cavity from groups of mice injected with lip.PZQ decreased most markedly on day 7 p.t., in the group treated with six doses of the drug. In the liver, the highest larvicidal effect, compared with the controls, was observed 6 days later (i.e. day 13 p.t.), following three doses of lip.PZQ. In all treated groups, two peak values of antitetrathyridial antibody levels were detected between days 1 and 13 p.t. (i.e. days 17 to 29 p.i.), after which there was a gradual but continuous increase in antibody titre. After treatment with six doses of both drug formulations (PZQ and lip.PZQ), the occurrence of the first maximum and minimum of antibody serum levels was delayed 6 days, compared to those groups treated with three doses of the drugs. Empty liposomes had some immunomodulatory effect on the antibody response, with significant decrease in antibody titres after three doses over the experimental period, but not after six doses.
Distribution of cobalt in parasitic helminths
Authors: Chowdhury N. , Singh R.
Published: June 2009

The distribution of cobalt in parasitic helminths belonging to the trematodes, cestodes or nematodes was determined by the use of an atomic absorption spectrophotometer. The results of these analyses have demonstrated that growing trematodes (smaller forms) with active oogenesis and spermatogenesis contained more cobalt than older forms (large or very old adults) with empty uteri and large lobulated testes. In cestodes, the neck region of cysticerci and immature proglottids of adults showed more cobalt than the cyst portion of cysticerci and hydatid or mature and gravid proglottids of worms. Similarly, the youngest endogenous daughter cysts of Echinococcus granulosus showed more cobalt in their walls than those of larger forms. The element was found more concentrated in nematode eggs than in adult females, irrespective of species of host.
Ultrastructure and histochemistry of the tegument of juvenile paramphistomes during migration in Indian ruminants
Authors: Mattison R.G. , Hanna R.E.B. , Nizami W.A.
Published: June 2009

The tegument of juvenileParamphistomum epiclitumandFischoederius elongatus(Paramphistomidae: Digenea) resembles those of other digeneans. Seven types of papillae were observed, mostly on the oral and acetabular surfaces, and increase in number during migration. Also evident are two types of secretory body (T1 and T2) which are synthesized separately in tegumental cytons underlying the syncytium. Exocytosis of T2 bodies occurs at the apical membrane and appears to contribute to a fibrous glycocalyx. The tegumental syncytium lining the pharynx and acetabulum is thinner and has a higher capacity for vacuolation than the general tegument. These may represent important sites for osmoregulation. The absence of mitochondria from the tegument in migrating juveniles suggests limited involvement in energy demanding processes. Pigmentation of the subtegument is first evident in mature cercariae and is progressively eliminated during migration.
Prevalence of Toxocara canis ova in public playgrounds in the Dublin area of Ireland
Authors: O'Lorcain P.
Published: June 2009

A total of nine playground sites in Dublin city and county were surveyed from which 228 samples were removed. Of these samples, 15% were positive for Toxocara canis ova and a mean egg density of 1.4 ova/100 g was calculated. Two types of playground sites were identified and that the level of toxocaral contamination was found to be greater in ‘neighbourhood playgrounds’ than in ‘adventure playgrounds’. There was no significant difference in the number of positive samples taken from sites both inside and outside these playgrounds. No evidence of Toxocara cati ova was found. Only one sample was positive for Toxascaris leonina ova. Over 50% of the T. canis ova identified were infective. The findings in this study suggest that the sample's moisture content contributes to the long term survival of infective Toxocara ova in the environment. A recovery rate of 69.8% was achieved with a modified version of the flotation method.
A hidden break in the 28.0S rRNA from Diphyllobothrium dendriticum
Authors: Karlstedt K. A. , Paatero G. I. L. , Mäkelä J.-H. , Wikgren B.-J.
Published: June 2009

Nondenatured and denatured total RNA from the tapeworm Diphyllobothrium dendriticum (Cestoda) was analysed by agarose gel electrophoresis. It was found that the large subunit ribosomal RNA (lrRNA) is 28.0S and the small subunit ribosomal RNA (srRNA) is 19.5S. Following denaturation the 28.0S rRNA was disrupted into a 19.5S subfragment and a 20.7S subfragment due to the presence of a centrally located hidden break. By hybridization of Northern blot membranes with oligonucleotide probes specific for the 5′- and 3′-ends of the lrRNA respectively, we have shown that the 19.5S sub-fragment is from the 5′-end (the α-subfragment) and the 20.7S subfragment from the 3′-end (the β-subfragment) of the 28.0S rRNA of D. dendriticum.
Influence of desiccation of faeces on survival and infectivity of first-stage larvae of Muellerius capillaris and Neostrongylus linearis
Authors: Morrondo-Pelayo P. , Diez-Baños P. , Cabaret J.
Published: June 2009

First-stage larvae of pure strains of M. capillaris and N. linearis (Nematoda: Protostrongylidae) from goats were used to assess the influence of rapid desiccation on survival. M. capillaris survived desiccation of faeces better than N. linearis. The latter species was particularly susceptible to duration of storage after desiccation (0 to 10 days). Surviving larvae of desiccated batches of M. capillaris were less able to infect the land-snail Candidula intersecta. Resistance of first-stage larvae to desiccation is a key factor in infectivity and may partly account for the geographical distribution of the two species of protostrongylids.
Treatment of Nippostrongylus brasiliensis in normal and SPF rats using tetramisole loaded into zeolite
Authors: Shaker S. K. , Dyer A. , Storey D. M.
Published: June 2009

Administration to rats of tetramisole loaded into zeolite was more successful in killing adults of Nippostrongylus brasiliensis than the administration of tetramisole alone. The most successful treatment occurred in SPF (Specific Pathogen Free) rats dosed with tetramisole loaded into zeolite and no worms were present in this group at autopsy eight days post-infection. It is concluded that the slow release of drug from the zeolite matrix improved its efficacy, especially in removing worms from low-grade infections.