bluuebunny/crossref_metadata_2025 huggingface dataset:
Endemicity, focality and seasonality of transmission of human schistosomiasis in Amagunze Village, eastern Nigeria
Authors: Ozumba N. A. , Christensen N. Ø. , Nwosu A. B. C. , Nwaorgu O. C.
Published: June 2009

The pattern of transmission of human schistosomiasis was studied in Amagunze Village, eastern Nigeria, during 1986–1987. The prevalence of Schistosoma haematobium in 119 schoolboys aged 5–12 years was 79%. The geometric mean of intensity of infection was 49 eggs/10 ml urine and the frequency of visible haematuria was 25·2%. No S. mansoni infections were demonstrated. A marked seasonality in population density of Bulinus truncatus, B. forskalii and Biomphalaria pfeifferi was demonstrated with reduced densities during the late rainy and early dry seasons. Schistosoma sp. infected B. truncatus were found in the late dry and early rainy seasons in 2 out of 7 major human water contact sites studied. Seasonality and focality of transmission of S. haematobium and its high endemicity in the area were thus demonstrated.
Studies on host specificity inParagonimus westermani: II. Histochemical and cytochemical characterization of metacercariae and worms from rats and dogs
Authors: Fujino Takahiro , Fukuda Koichi , Hamajima Fusanori , Ishii Yoichi
Published: June 2009

Histochemical tests were done on newly excysted metacercariae and worms recovered from an abnormal host (rat) and the definitive host (dog) for some oxidoreductases, phosphatases and glycosidases. The results demonstrate that rat worms have enzymatic distribution and intensities more similar to those of metacercariae than to adult worms from dogs. Ultracytochemical examination of acid and alkaline phosphatase and Mg-ATPase activity was also carried out. Acid phosphatase activity occurred exceptionally in the excretory bladder and caeca of dog worms. No activity was observed in rat worms except for lysosomal granules in the tegument. Alkaline phosphatase activity was exhibited in the excretory bladder in both dog and rat worms. Mg-ATPase activity occurred in the tegument and parenchymal cells in dog worms and in the excretory bladder in rat worms. In metacercariae, little or no reaction for these enzymes was present except for Mg-ATPase activity on the excretory ducts. These observations, together with the histochemical results, indicate that metabolic activity in rat worms is higher than in metacercariae although it is strongly reduced compared with dog worms.
Rapid recovery of Echinococcus granulosus following ‘successful’ albendazole therapy in a gerbil model
Authors: Taylor D. H. , Richards K. S. , Morris D. L.
Published: June 2009

Peritoneal Echinococcus granulosus in gerbils was treated with albendazole. Both early and late infections were studied; response to albendazole therapy and the ability of the parasite to recover after treatment was found to depend on dose and length of therapy. Even after treatment at 50 mg/kg for 2 months late infections retained the ability to recover over 3 months.
Pulmonary superoxide dismutase activity in the mouse infected withAncylostoma caninumlarvae
Authors: Kulkarni A. B. , Bhopale M. K. , Sharma K. D.
Published: June 2009

Albino mice were infectedper oswith 1000 infective larvae ofAncylostoma caninumand pulmonary superoxide dismutase activity was studied after completion of lung migration. The total superoxide dismutase activity per mg of lung protein was elevated by 15% in infected mice. Of the two forms of superoxide dismutases studied, that containing Cu-Zn was elevated by 44%. this suggests thatA. caninumin mice may result in histopathological changes leading to transient pulmonary oxygen toxicity.
Absence of shock-like reactions to ivermectin in dogs infected with Dirofilaria immitis
Authors: Boreham P. F. L. , Atwell R. B.
Published: June 2009

Six dogs infected with Dirofilaria immitis and known to develop shock-like reactions after administration of diethylcarbamazine (DEC) were given ivermectin 50μg/kg orally. None of the dogs showed any adverse reaction and subsequently all reacted to DEC 20mg/kg orally.
Helminth parasites of Jamaican anoles (Reptilia: Iguanidae): a comparison of the helminth fauna of 6Anolisspecies
Authors: Bundy Donald A. P. , Vogel Peter , Harris Eileen A.
Published: June 2009

Prevalence and intensity of helminth parasites are described for a sample of 102 Jamaican anole lizards representing 6 species (Anolis lineatopus lineatopus, A. I. neckeri, A. grahami, A. valencienni, A.opalinus, A. sagrei, A. garmani). Fifty nine per cent of lizards were infected with 5 species of nematodes, 16% with one acanthocephalan, 7% with two digeneans, and 4% with a single cestode species. Infection intensity was generally low (intensity range 1–5) although two species of nematode occurred in very large numbers (intensity range 1–436). Helminth prevalence patterns and species composition reflected differences in anole habitats rather than ecomorphs, and were uncorrelated with the genetic relatedness of indigenous versus introduced anole species.
Inhibition phenomena mechanisms in experimental obeliscoidosis in rabbits. II. Local and systemic antibody responses
Authors: Helal I. B. , Wedrychowicz H. , Sinski E. , Bezubik B.
Published: June 2009

A series of experiments was carried out using adult outbred Polish race rabbits of both sexes infected, during spring or autumn. with 10 000 larvae of Obeliscoides cuniculi, either fresh or stored at 4°C. Extracts of mucosal proteins and bile were collected at postmortem 6 or 12 weeks after infection. Antibody levels were determined in antisera. bile and stomach mucosa by haemagglutination and precipitation tests. Local antibody respones were demonstrated in the stomach and bile, and reactions were obtained with the tissue fluids by haemagglutination and precipitation tests with worm antigens and ES products. Additionally, some specific immunological response was observed in the circulation during the primary infection. These results suggest a clear-cut relationship between increased levels of these antibodies and either larval inhibition or worm expulsion during O. cuniculi infections.
Drug activity against Onchocerca gutturosa males in vitro: a model for chemotherapeutic research on onchocerciasis
Authors: Townson Simon , Connelly C. , Dobinson A. , Muller R.
Published: June 2009

An in vitro system for chemotherapeutic research using adult male Onchocerca gutturosa has been developed as a model for O. volvulus. Using a culture system consisting of medium MEM+10% heat inactivated foetal calf serum (IFCS)+LLCMK2 (monkey kidney) feeder cells in an atmosphere of 5% CO2 in air, we examined the effects of a range of antiparasitic drugs on worm motility. Ivermectin, levamisole, furapyrimidone, Mel W, chloroquine, metrifonate, flubendazole, amoscanate and the Ciba-Geigy compounds CGP 6140, CGP 20′376 and CGI 17658 either immobilized or significantly reduced motility levels at a concentration of 5x10−5M or less within a 7-day period. Worms were affected at very low concentrations by ivermectin (effective conc. to reduce motility levels to 50% of controls, 3.14x10−8M), levamisole (7.95x10−8M), CGP 6140 (8.87x10−9M) and CGP 20′376 (2.78x10−8M). Difficulties were experienced in accurately repeating the immotile endpoint for levamisole due to an inconsistent partial recovery of motility. Over a 7-day period diethylcarbamazine had little effect on motility levels, while suramin caused a slight increase in activity compared to controls at some timepoints. Subsequent experiments demonstrated some differences in drug efficacy depending on the presence or absence of serum and feeder cells in the culture system probably because of drug avidly binding to serum proteins. However, serum and cells were found to be essential ingredients of the culture system to maintain worms in good condition, indicating that new drugs should be evaluated both in the presence and absence of serum and cells. Comparisons were made between the responses of O. gutturosa and Brugia pahangi to certain drugs and these species were found to significantly differ in their sensitivities to ivermectin and a novel compound (Wellcome), indicating that Onchocerca parasites should be used wherever possible for compound identification and development intended for the treatment of onchocerciasis. The in vitro system described here, using male O. gutturosa, provides a basis for further research and a practical alternative to O. volvulus.
Infectivity of Hymenolepis nana eggs from faecal pellets in the rectum of mice
Authors: Maki Jun , Yanagisawa Toshio
Published: June 2009

The infectivity of Hymenolepis nana eggs from faecal pellets in the rectum of mice was compared with that of the eggs in gravid proglottids of adult H. nana and with that of the eggs in excreted faecal pellets to find out a simple method for collecting H. nana eggs of high infectivity to mice. Eggs from faecal pellets in the rectum showed higher infectivity than those from gravid proglottids and as high infectivity as those from gravid proglottids selected by a watch-glass rotation technique. Eggs in faecal pellets in the rectum did not lose infectivity until 4 h after they were excreted and exposed to the air at room temperature (27–28°C) with relative humidity of 35–40%. However, the eggs lost infectivity significantly 17 h after excretion onwards.
Chromosome study of Isoparorchis hypselobagri Billet, 1898 (Digenea: Hemiuridae)
Authors: Chattopadhyay I. , Manna Buddhadeb
Published: June 2009

Chromosomal complements of an oocyte and a fertilized ovum from the ootype of Isoparorchis hypselobagri Billet, 1898 have been studied. Twenty diploid and 10 haploid chromosomes have been observed. In the karyotype the presence of five submetacentric, four acentric and a pair of sex chromosomes provide a significant cytotaxonomic information.
The route of infection of Paragonimus westermani (diploid type) cercariae in the freshwater crab, Geothelphusa dehaani
Authors: Shibahara Toshiyuki
Published: June 2009

The different routes of infection of Paragonimus westermani (diploid type) in the freshwater crab, Geothelphusa dehaani, were experimentally confirmed by various methods. In all the experiments, P. westermani metacercariae were recovered from the muscles, gills and liver of the infected crabs with the cercariae, although they were smaller than those of naturally infected ones. This is the first experimental evidence that G. dehaani is infected by both oral feeding and percutaneous contact with P. westermani (diploid type) cercariae.
Secretion and excretion of endogenously synthesized lipids by adultHaemonchus contortus in vitro
Authors: Kapur Jyotika , Sood M. L.
Published: June 2009

Results of the incorporation of carbon from14C-glycerol into total, polar and nonpolar lipids inHaemonchus contortus(Nematoda: Trichostrongylidae) reveal that the radioactivity lost into the medium as lipids decreased during the first 3 h of incubation. This was followed by a drastic increase during the 4th h. Again, there was a decline by 75% during the 5th h. However, there was a slight increase in the nonpolar lipids during the 5th h.
Factors influencing the egg production of Ascaris lumbricoides: relationship to weight, length and diameter of worms
Authors: Sinniah B. , Subramaniam K.
Published: June 2009

Fifty children aged 6 to 13 years and infected with Ascaris lumbricoides were selected for the study. The number of eggs laid daily by a female Ascaris increased with increase in its length, weight and diameter. Female worms became mature and started laying eggs when they reached a length of 118 mm. Adult female worms measuring 3·7 mm or more in diameter were found to be mature. The minimum weight of a worm producing eggs was 1·1 g. On average the number of eggs produced by the female decreased with increase in the worm load.
Effect of water temperature on the ability of Diplostomum spathaceum miracidia to establish in lymnaeid snails
Authors: Waadu G. D. B. , Chappell L. H.
Published: June 2009

The effects of water temperature on the ability of Diplostomum spathaceum miracida to infect and establish patent infections in Lymnaea peregra and L. stagnalis were investigated. Snails were infected over a range of temperatures (6–20°C) and kept thereafter at 20°C or were infected at 20°C and kept at either 14, 20, or 25°C. Infection success was determined after 8 weeks by either observing cercarial shedding or examining snail viscera for sporocysts. The establishment of miracidia declined at lower water temperatures despite maintenance for 8 weeks at 20°C while exposure of snails to miracidia at 20°C and maintenance at different temperatures had little apparent effect. Infection success under these conditions was related more to the numbers of miracidia to which the snails were exposed. However, under this latter experimental regime, the time taken for the infection to become patent clearly depended upon maintenance temperature.
First record of the larval parasitic nematode Rhabditis orbitalis from Japanese wood mice (Apodemus spp.)
Authors: Sudhaus W. , Asakawa M.
Published: June 2009

Parasitic larvae of Rhabditis orbitalis (formerly confused with Pelodera strongyloides) were found in the conjunctival sacs of the eyes of Apodemus argenteus and A. speciosus from Japanese islands.
The effects of crowding on adults of Echinostoma caproni in experimentally infected golden hamsters
Authors: Yao G. , Huffman J. E. , Fried B.
Published: June 2009

Fifty-nine of 60 (98%), 6-month-old male golden hamsters, Mesocricetus auratus, fed 15 (group A). 50 (group B), or 200 (group C) metacercarial cysts of Echinostoma caproni (Digenea: Echinostomatidae) were infected 7–34 days postexposure. The mean number of worms recovered in groups A, B and C were 9, 10, and 50, respectively. The percentage recovery was significantly different between group A (63%) and groups B (21%) and C (23%). The intestine was divided into three equal regions (I, II, III). Worms from group A were located in segments II and III of the small intestine whereas worms from groups B and C were distributed in all three segments. The body area, ovarian and testicular areas of worms from group A were greatest, followed in decreasing order by body and gonadal areas of worms from groups B and C. Echinostoma caproni eggs were found in the faeces of all the hamsters examined from groups A, B and C by days 9, 10 and 11, respectively. Physical damage occurred at the site of attachment of the echinostome. Pathological observations indicated the presence of enlarged lymphatic nodules with lymphocytes being the primary cellular infiltrate at the site of parasite attachment.
Factors influencing the metacercarial intensity in ants and the size of Dicrocoelium dendriticum metacercarial cysts
Authors: Schuster R.
Published: June 2009

During the 1990 grazing season, ants found attached to plants were collected from sheep pastures at monthly intervals and examined for Dicrocoelium metacercariae. The species Formica pratensis and F. rufibarbis showed average metacercarial intensities of 76 and 38 respectively. In addition to the ant species, the intensity of infection was found to be dependent on the length of the ant. The volume of metacercarial cysts was influenced by the intensity per ant relative to ant length but not by the ant species or the time of ant collection.
Experimental infection routes of Angiostrongylus cantonensis in mice
Authors: Wang Lian-Chen , Chao David , Chen Eng-Rin
Published: June 2009

Stomach intubation is the most common method used in the experimental infection of animals with Angiostrongylus cantonensis. In order to compare the effectiveness of other possible transmission methods, groups of BALB/c mice were given infective third-stage larvae of A. cantonensis by different routes including intraperitoneal or subcutaneous injections, and penetration of anal mucosa, vaginal mucosa, conjunctival mucosa, lacerated skin, unabraded skin, foot pad and tail skin, while stomach intubation was used as control. Recovery of fifth-stage larvae was higher in mice inoculated with third-stage larvae subcutaneously. Successful infections were established through all experimental transmission routes except tail skin penetration. This study suggests that oral infection may not be the only route for the transmission of human angiostrongyliasis, and subcutaneous infection may be a better method for experimental infection.
Onchocerca raillieti: adult location and skin distribution of the microfilaria in Sudanese donkeys
Authors: El Sammani Saad E. , Hussein Hussein S.
Published: June 2009

Onchocerca raillietiis the onlyOnchocercaspecies infecting Sudanese donkeys; it occurs only in the ligamentum nuchae, especially in the lamellar part of the ligament. The morphological features of both uterine and skin microfilariae were determined. Skin microrilariae are shorter than uterine ones and tend to accumulate in the regions ofLinea albaand withers of infected donkeys. The possible identity of the vector of this worm in the Sudan is discussed.
A simple method for the oral transfer ofMoniliformis moniliformis(Acanthocephala) between rats
Authors: Stoddart R. C. , Crompton D. W. T.
Published: June 2009

A technique is described whereby young adultMoniliformis moniliformis, aged up to 7 days, can be transferred via the oral route from one rat to another. The method is dependent on giving the recipient rats a dose of Cimetidine (0·25 ml/250 g body weight of a solution containing 950 mg/ml) 1 h before transfer. Cimetidine functions as an H2-receptor antagonist and gastric acid secretion in the rat is inhibited temporarily. The technique does not appear to interfere with the reproductive biology of the parasite.
Long-term infection withSchistosoma mansoni(Gezira strain—Sudan) in the Nile rat (Arvicanthis niloticus)
Authors: El Hussein Durria M. , Sulaiman Suad M.
Published: June 2009

The long-term infection withSchistosoma mansoni(Gezira strain—Sudan) was studied in the Nile rat (Arvicanthis niloticus) to investigate the ‘self cure’ phenomenon. The results indicated that while a considerable number of worms and eggs were still recovered by week 28 post-infection, elimination of some of the worms occurred by week 20.
Ascorbic acid levels in the proglottides of four species of cestode parasites of mammals and birds in relation to their sexual maturity
Authors: Tandon R. S. , Gupta Sushma
Published: June 2009

Ascorbic acid levels were found to be closely related to different stages of growth and maturity of Avitellina centripunctata, Moniezia expansa, and Stilesia globipunctata from goats and sheep and of Raillietina echinobothrida from fowl. The ascorbic acid level in avian parasites was higher than that in mammalian. The level was highest in immature proglottides and lowest in gravid proglottides.
Molecular analysis of the gene encoding an antigenic polypeptide ofTrichinella spiralisinfective larvae
Authors: Sugane Kazuo , Matsuura Tadashi
Published: June 2009

The gene encoding an antigenic polypeptide ofTrichinella spiralisinfective larvae was studied using recombinant DNA techniques. cDNA synthesized from poly(A)-rich mRNA fromT. spiralisinfective larvae was ligated into phage vector λgt11 DNA and packagedin vitro. The phages were propagated onEscherichia coliand a λgt11 expression library was constructed. A cDNA clone encoding a 46 kDa antigenic polypeptide was selected by immunoscreening of the library and identified by the epitope selection method. A clone containing nearly full-length cDNA for a 46 kDa protein was isolated. The gene encoding this 46 kDa antigenic polypeptide was characterized by DNA and RNA blot analysis using the cDNA as a probe. The gene was transcribed to mRNA with approximately 1400 nucleotides and translated to 46 kDa polypeptide. The antigenic polypeptide was excreted/secreted as a 46 kDa native antigen. The antigenic β-galactosidase fusion protein synthesized by bacteria had no cross-reactivity with other parasite-infected sera.
The presence of pinworms (Enterobiussp.) in the mesenteric lymph nodes, liver and lungs of a chimpanzee,Pan troglodytes
Authors: Zhang Guang-Wen , Ji Xiang-Rui , McManus Donald P.
Published: June 2009

This report describes a case of fatal enterobiasis caused byEnterobiussp. in the mesenteric lymph nodes, lymphatic vessels of mesentery, blood vessels of the liver and lungs of a chimpanzee from Qingdao Zoo, China. Based on pathological findings, it is likely that the pinworms obtained access to these organs via the lymphatic or haematogenous pathway. As far as we are aware, this is the first reported case ofEnterobiussp. in the mesenteric lymph nodes and blood vessels of the lungs and veins of the hepatic triad in a chimpanzee.
Tricarboxylic acid cycle enzymes of a pseudophyllid cestode Penetrocephalus ganapatii
Authors: Dhandayuthapani S. , Nellaiappan K.
Published: June 2009

Studies on the tricarboxylic acid cycle (TCA cycle) enzymes of Penetrocephalus ganapatii reveal that the TCA cycle is only partially operative, as some of the enzymes at the start of the cycle viz. citrate synthase, aconitase and isocitrate dehydrogenase are found to be low in their activities. The high activities of malate dehydrogenase and fumarase, showing affinity towards a reverse direction, indicate that the TCA cycle operates in the reverse direction resulting in the formation of fumarate. The low succinate dehydrogenase/fumarate reductase ratio suggests that ATP generation may occur at site I of the respiratory chain during the reduction of fumarate into succinate.
Single and multiple worm infections of Echinostoma caproni (Trematoda) in the golden hamster
Authors: Fried Bernard , Huffman Jane E. , Weiss Patricia M.
Published: June 2009

Six of 10 hamsters fed a single metacercarial cyst of Echinostoma caproni (single-worm infections) and 13 of 19 hamsters fed either 2 or 5 cysts (multiple-worm infections) were infected with adult echinostomes at necropsy 22 days post-infection. Considerable histopathological changes to the small intestine occurred in hamsters carrying single-worm infections. There were no differences in either mean length, width or wet weight of echinostomes in single- versus multiple-worm infections. The mean number of eggs/worm from single-worm infections (525) was significantly greater than that from multiple-worm infections (288). The average percentage of fully developed miracidia/worm from single worms (94%) was similar to that from worms in multiple infections (92–95%). Single worms of E. caproni were capable of self-fertilization and production of viable eggs. Miracidia derived from single worms were as capable of infecting laboratory-reared Biomphalaria glabrata and producing patent rediae as were those from multiple infections.
The epidemiology of the metacercariae of Diplostomum baeri and D. spathaceum in perch (Perca fluviatilis) from the warm water effluent of a nuclear power station
Authors: Höglund Johan , Thulin Jan
Published: June 2009

Thermal effects on the dynamics of infection with metacercariae of Diplostomum baeri and D. spathaceum were monitored between May and September, in a year-class of perch Perca fluviatilis, in an artificial lake receiving warm water discharges from a nuclear power station and in an unheated reference site, for a two year period. In the heated area the prevalence of infection of the retinal form, D. baeri, was always 100%, whereas in the unheated site there was an increase from 93% in May to 100% in June 1986. The relative density of D. baeri was found to increase gradually during the first summer in both areas, although the accumulation rate of metacercariae was significantly increased in the heated area. In August of the first year the relative density of D. baeri peaked in the heated area, whereas it continued to increase in the unheated control. However, in September of the following year, the relative densities were at the same level in both thermal regimes. A concomitant decline in the degree of overdispersion of metacercariae within the host population was observed in the heated area as the population density of metacercariae decreased, whereas the index of dispersion remained at the same level throughout the study in the unheated area. However, it was not possible to sample perch in the unheated area between October 1986 and May 1987 and changes in the parasite population could have occurred during this period. The prevalence and relative density of D. spathaceum, the lens form, was on the contrary low, especially in the unheated site where it was recorded only occasionally. The infection of D. baeri exhibited a convex pattern in both thermal regimes, although the peak infection was noticed earlier in the heated area. Regulation of the parasite infrapopulation may have been achieved by the combined effects of a decreased transmission rate of cercariae with increasing age of the host, the mortality of metacercariae as a natural termination of the life span and to selective predation of heavily infected hosts. However, regardless of an increased accumulation rate of metacercariae in the heated area, the relative densities of D. baeri became equal in both thermal regimes at the end of the study. The mortality rate of metacercariae in the heated area was therefore presumably increased as compared with the unheated reference site.
Establishment, development and fecundity of Taenia crassiceps in the intestine of prednisolone-treated Mongolian gerbils and inbred mice
Authors: Sato Hiroshi , Kamiya Masao
Published: June 2009

Worm establishment, development and fecundity of Taenia crassiceps in the intestine of prednisolone (PTBA)-treated, 15- and 4-week-old Mongolian gerbils and 9-week-old inbred mice of 4 strains (AKR/J, BALB/cAn, B10D2/oSn and C57BL/KsJ) were investigated following oral administration of metacestodes. Gerbils were divided into 5 groups of 4 animals each according to the host age and commencement day of PTBA-treatment (day −13, −7 or 0 relative to infection). Worm recovery from the intestine on day 35 postinfection was not affected by host age, but fewer worms were recovered the earlier the commencement of PTBA-treatment. Worm size, determined by wet weight, total length and proglottis number, correlated inversely with worm burden, suggesting they were affected by the crowding effect. Proglottides were released normally in the faeces but were markedly depressed in all groups except for that of young gerbils. Furthermore, egg production and its development in gravid proglottides were markedly depressed in all groups. In PTBA-treated mice of 4 strains, sexually mature but not gravid worms were recovered from all mice of the AKR/J strain on days 20–32 postinfection, but none or few worms from the intestine of the others. PTBA-treatment did not inhibit all protective host defence mechanism(s) in the unnatural or alternative rodent definitive host of T. crassiceps.
Observations on the morphology ofToxocara pteropodiseggs
Authors: Prociv Paul
Published: June 2009

Fertile eggs ofToxocara pteropodis, passed in the faeces of juvenile flying-foxes, were ovoid to spheroid in shape with a diameter range of 80–110 µm. The shell was often seen to comprise 4 layers: a fine inner lipid layer, a thicker clear chitinous layer, an equally thick outer vitelline layer and a pitted outermost, proteinaceous uterine layer of variable thickness. Infertile eggs were less uniform in shape and generally did not have well-defined shell layers, the formation of which is triggered by sperm penetration of the oocyte. The eggs of this species are bulkier than those of related ascaridoids, apparently because of a thicker external coat which, while not providing mechanical strength, is thought to protect against desiccation. Scanning electron microscopical findings suggest that the outer layer is not applied directly by uterine cells, but forms by the gradual deposition of secretions in the uterine lumen, regardless of whether the oocyte has been fertilized.
Seasonal variation in the prevalence and intensity of canine Gnathostoma spinigerum infection in northeastern Thailand
Authors: Maleewong W. , Pariyanonda S. , Sitthithaworn P. , Daenseegaew W. , Pipitgool V. , Tesana S. , Wongkham C. , Intapan P. , Morakote N.
Published: June 2009

Gnathostoma spinigerum was found in gastric nodules in 4·1% of 2940 dogs surveyed in northeastern Thailand. The prevalence and worm burden of G. spinigerum exhibited a seasonal fluctuation. The parasites were more abundant in the rainy season and the early winter (August–December) than in the summer (April–March). Most parasites were sexually mature between August and December while immature worms were observed during March and April. The distribution of gnathostomes within the sampled dogs was highly dispersed and few animals were found to harbour more than five worms.
Seroprevalence of Toxocara canis antibodies in humans in northern Jordan
Authors: Abo-Shehada M. N. , Sharif L. , El-Sukhon S. N. , Abuharfeil N. , Atmeh R. F.
Published: June 2009

Sera of 699 individuals, aged between 5–24 years, from the Irbid area. Jordan, were tested for Toxocara canis antibodies using an ELISA-IgG test. Crude prevalence was 10·9% (76 of 699) but age-adjusted prevalence was 14·3%. The highest prevalence was observed in females aged 5–9 years. 23·3% (7 of 30). and males of 15–19 years of age. 19·5% (16 of 82). The lowest prevalence was observed in females aged 20–25 years. 5·2% (8 of 155). Significant differences (P<0·05) between the prevalences of the toxocaral antibodies in males and females were observed in the age groups 5–9, 15–19 and 20–24 years. The trend of prevalence in relation to age was different according to sex.
Comparative cytotoxicity of secondary hydatid cysts, protoscoleces, and in vitro developed microcysts of Echinococcus granulosus
Authors: Janssen D. , Osuna A. , Lazuen J. , De Rycke P. H.
Published: June 2009

Infection with the metacestode of Echinococcus granulosus is characterized by a concomitant immunity. Survival of established and developing hydatid cysts in the intermediate host implies a mechanism to modulate its immunological reactions. In order to investigate this mechanism, secondary hydatid cysts were isolated from intraperitoneally infected laboratory white mice (strain NMRI) 12 months p.i. A number of hydatid cysts were freed from the surrounding host adventitial tissue. Monolayer cultures of non-stimulated peritoneal macrophages of NMRI mice were prepared and incubated in the presence of the hydatid cysts. By means of a trypan blue exclusion test and by measuring the incorporation of tritium labelled uridine, it was found that the presence of hydatid cysts reduced the viability of the macrophages in vitro. Toxic substances are probably secreted since the medium of cultured hydatid cysts also displayed cytotoxic activity. Hydatid cysts with adventitia, as well as culture medium of those cysts, were less toxic. When toxins, partially purified from hydatid cyst fluid, were previously incubated on a collagen coated surface, a reduced level of toxicity was found, suggesting that collagen of the host adventitia may play a role in controlling the liberation of toxins by the hydatid cyst. Virtually no toxicity was exerted by protoscoleces or by the medium of cultured protoscoleces, in contrast to in vitro vesiculated protoscoleces (so called microcysts). The results reveal a novel feature of hydatid cysts that may play a role in the survival of the parasite in the immunized host.
Prevalence of Toxocara eggs and number of faecal deposits from dogs and cats in sandpits of public parks in Japan
Authors: Uga Shoji
Published: June 2009

Contamination of 13 sandpits in public parks in Hyogo Prefecture, Japan, by Toxocara eggs and animal faeces was studied. All 13 sandpits were contaminated with faeces. The mean number of faeces found in 1 m2 of the sandpits was 35, from which the number of faeces in each sandpit was estimated to be 261 to 2205. Toxocara eggs were detected in 12 of the 13 sandpits, each examined 4–15 times; the overall prevalence was 92%. The eggs were not always distributed in the same pattern, but in general, eggs were numerous on the sandpit surface but also present at depths of about 35 cm. Of the eggs recovered, 63% were fully embryonated. Of the 13 sandpits examined, two were heavily contaminated by eggs, and all but one of the others were mildly contaminated. The difference between heavy and light contamination was not related to differences in the environment or in the number of faeces; the cause is unknown.
Distribution of some elements in hydatid cysts of Echinococcus granulosus from buffalo (Bubalus bubalis)
Authors: Chowdhury N. , Singh Rajvir
Published: June 2009

Distribution of some elements during development of endogenous daughter (hydatid) cysts of Echinococcus granulosus of buffalo origin was determined by atomic absorption spectrophotometry. These analyses showed that the distribution of copper and cobalt was highest in the smallest cysts. These elements gradually decreased in the cysts as they enlarged. The distribution of zinc, iron and manganese was very high in the smallest cysts in comparison to copper and cobalt, but these three elements decreased greatly in larger cysts. Iron and manganese were the only two elements found in very high concentrations in “thin-walled” cysts. Like all other elements both calcium and magnesium decreased as the cysts increased in size. In the thin-walled cysts magnesium increased by four times initially and this was followed by a two-fold “influx” of calcium in the “white-spots” in the above cysts. The significance of these findings is discussed in relation to earlier works.
Use of body fluid of adult femaleAscaris suumas an antigen in the enzyme-linked immunosorbent assay (ELISA) for diagnosis of swine ascariosis
Authors: Yoshihara S. , Oya T. , Furuya T. , Goto N.
Published: June 2009

The Enzyme-linked immunosorbent assay (ELISA) was used to detectAscaris suumantibodies in swine sera with adult body fluid (ABF) as an antigen. The assay was standardized with respect to the antigen concentration and serum and conjugate dilutions. Cross reaction was found between the antigen and the sera from the swine infected withMetastrongylus apri. The ELISA was more sensitive than the complement fixation test. Five protein peaks were obtained from ABF by gel filtration on Sephacryle S-300. Fraction I was the most specific. A 105 kDa protein in the fraction reacted with swine lgG in the serum of infected animals in Western blot analysis.
A seroepidemiological study of human Toxocara infection in the Slovak Republic
Authors: Havasiová K. , Dubinský P. , Stefancíková A.
Published: June 2009

Sera of 908 blood donors, average age 35 years, living in towns and villages of the Slovak Republic were tested for Toxocara canis antibodies using an ELISA-IgG test. The seroprevalence in the healthy population was estimated at 13·65%. Antibodies were predominantly demonstrated in the sera from persons living in rural communities (17·09%) compared to the sera investigated from urban communities (11·82%). Women had a significantly higher seropositivity than men. The serological response in 2703 sera from patients suspected of toxocarosis was compared with their clinical manifestation, sex and age. Toxocara antibodies were found in 27·41% of suspected patients. Although the seroprevalence in adults was significantly higher among women than men, in children, boys had a higher seroprevalence than girls. The main clinical manifestations were leucocytosis and eosinophilia (46%), ocular disorders (36%), lung, liver and neurological disorders (26%). The most severe forms of this disease were observed in 2 to 5-year-old children with geophagy.
Mitochondrial DNA differentiation of Japanese diploid and triploid Paragonimus westermani
Authors: Agatsuma T. , Yang L. , Kim D. , Yonekawa H.
Published: June 2009

Restriction endonuclease analysis of mitochondrial DNA was carried out in order to differentiate diploid and triploid types of Paragonimus westermani originating from Japan. It was found that out of 16 restriction enzymes. PstI, HaeIII and RsaI revealed consistently different cleavage patterns between the two types.
Efficiency of the salt flotation technique in the recovery ofAscaris lumbricoideseggs from the soil
Authors: Ajala M.O. , Asaolu S.O.
Published: June 2009

The efficacy of the salt flotation technique using saturated solutions of sodium nitrate (specific gravity 1.30) and zinc sulphate (specific gravity 1.16) for separatingAscaris lumbricoideseggs from clay, loamy and sandy soils has been investigated. Ten samples of each of the egg concentrations of 100, 500, 2500, 5000 and 10,000 eggs/25 g of soil were used for each soil type. Using T-test and ANOVA, the number of eggs recovered from sand was significantly higher than from loam and the number from loam significantly higher than from clay. With sodium nitrate, the maximum egg recovery rate was 25.04% from sandy soil at a concentration of 500 eggs/25 g soil while with zinc sulphate it was 13.88% also from sandy soil and concentration of 500 eggs/25 g soil. While the number of eggs recovered increased with soil egg concentration, the percentage of eggs recovered is inversely proportional to egg concentration. The number of eggs recovered with sodium nitrate was significantly higher than with zinc sulphate solution in the three soil types.
Development of the free-living stages ofHyostrongylus rubidusandOesophagostomumspp. at different temperatures and humidities
Authors: Fossing E.C. , Knudsen T.S.B. , Bjørn H. , Nansen P.
Published: June 2009

Faeces containing a mixture ofHyostrongylus rubidusandOesophagostomumspp. eggs were mixed with vermiculite and water and set up at combinations of different relative humidities (65.5%, 79.5%, 90.0% and 100%) and temperatures (5°C, 10°C, 15°C, 20°C, and 25°C) in order to study the rate of egg hatching and larval development. The study established that the development from egg to infective larva showed similar patterns for the two parasites. Optimum development and survival was in the temperature range from 15°C to 20°C and ata humidities from 79.5 to 95.5%.
Oxidation and reduction of cytochrome c by mitochondrial enzymes ofSetaria cervi
Authors: Goyal N. , Srivastava V.M.L.
Published: June 2009

A mitochondria-rich fraction isolated from the cuticle-hypodermis-muscie system ofSetaria cervi, a bovine filarial parasite, possessed substrate-coupled cytochrome c reductases and cytochrome c oxidase in appreciable activities. All these activities were located predominantly in the membranes. NADH-coupled cytochrome c reductase was more prominent than NADPH- and succinate-coupled reductases. All the three reductases exhibited marked sensitivity to rotenone and antimycin A. Salicylhydroxamic acid strongly inhibited succinate requiring reductase and cytochrome c oxidase, but the other two reductases only mildly. Sodium azide activated the reductases but substantially inhibited the oxidase activity. Potassium cyanide activated the succinate requiring reductase but did not cause any noticeable change in the activities of pyridine nucleotide linked reductases. Anthelmintics also influenced these activities but no definite correlation could be drawn regarding their mode of action.
Higher levels of passive compared with active immunity in rats immunized with larval antigens ofSchistosoma mansoni
Authors: Lawson B.W.L. , Bickle Q.D. , Taylor M.G.
Published: June 2009

We have previously shown that it is the lung stage schistosomulum which is both the inducer and the target of immunity in rats vaccinated with irradiated cercariae but that rats can also be partially protected by immunization with detergent extracts of mechanically-transformed schistosomula. In the present study we therefore compared the immunogenicity of these and intermediate schistosomular stages. In the first experiment low levels of protection (13–24%) were induced by extracts of mechanically-transformed schistosomula cultured for 3 hours or 2 days but not by extracts of lung schistosomula. In a repeat experiment insignificant levels of protection were induced by extracts of 3 h schistosomula and lung schistosomula were again non-protective. Nevertheless, high levels of anti-schistosomula antibodies were demonstrated and sera from actively immunized rats conferred significant passive protection in five out of six trials. The levels of protection conferred by passive immunization (26–51%) were in each case higher than the levels of protection demonstrated in the respective serum donor groups, showing that some form of immunological blockade suppression is operating to prevent expression of protective immunity in the actively immunized rats.
Faecal egg output, contamination of pastures and serum pepsinogen concentrations in heifers with natural gastrointestinal nematode infections in north-west Spain
Authors: Mezo-Menéndez M. , Díez-Baños P. , Morrondo-Pelayo P. , Díez-Baños N.
Published: June 2009

In 1988, 1989 and 1990 second year grazing heifers, naturally infected with gastrointestinal nematodes, were separated into two groups, one of which was treated orally with albendazole. In 1988 and 1989 treatment was administered immediately after parturition (February), and in 1990 during the last term of pregnancy (December). Both treated and control animals were grazed on separate plots in a rotational system. Maximum faecal egg counts were observed amund parturition, except in 1990, when treatment was given at the end of gestation. The main genera identified wereCooperia, Trichostrongylus, OstertagiaandOesophagostomum. The number ofOstertagialarvae in the treated groups increased from 1989 to 1990, while the others decreased. Pasture contamination with third stage larvae (L3) was lower on the piots grazed by treated heifers. Maximum numbers of L3 were found in autumn, at the end of winter, and at the beginning of spring. Mean serum pepsinogen concentrations were significantly higher in the untreated groups. This concurs with the pattern for L3 on pasture. The trial shows that if a single treatment against gastrointestinal nematodes is carried out, and the animals remain on contaminated pastures, the parasitic load tends to level out after 4–5 months under favourable climatic conditions. However, the percentages of nematode genera occurring in the new populations may differ from those in the original infection.
Morphological comparison of in ovo derived and naturally occurring flukes using Microphallus similis, M. pygmaeus and Maritrema arenaria
Authors: Strain L.C. , Irwin S.W.B.
Published: June 2009

This investigation deals with the evaluation of the in ovo technique for the cultivation of trematodes. The technique has previously been used for the maturation of digenetic flukes and the establishment of life cycles in the laboratory but it was not known if the adult flukes produced were morphologically comparable to those found in their natural hosts. Three species of microphallids, Microphallus similis, M. pygmaeus and Maritrema arenaria were used. Metacercariae of each species were inoculated into fertile hen's eggs which were incubated at 41°C for 120 hours. The adult flukes recovered were stained and mounted and morphonietric measurements obtained were compared to definitive descriptions of the three microphallid species. The results showed that the in ovo technique provided adult flukes which were indistinguishable from those occurring in natural hosts.
Effect of mercury on the immune response and mean intensity ofAscaris suuminfection in guinea pigs
Authors: Borošková Z. , Šoltys J. , Benková M.
Published: June 2009

The subchronic effect of mercury on selected immunological parameters was studied in guinea pigs with experimentalAscaris suuminfection. HgCl2given for 28 days reduced significantly T- and B-cell populations in the lymphoid organs and the phagocytic ability of peritoneal macrophages. The subsequent infection of HgCl2-intoxicated animals elevated the studied immunological parameters, but in comparison with infected non-intoxicated guinea pigs they remained significantly suppressed. The mercury compound in infection stressed animals caused a slight alteration of the complement CH50and AH50activity. The specific circulating antibody level in infected and HgCl2treated animals rose a little by day 12 p.i. and then again decreased significantly, compared with untreated guinea pigs. The mean intensity of infection with migratingAscarislarvae in HgC12-treated animals increased by 15%, compared with controls.
Metazoan parasite community structure in brown trout from two lakes in western Ireland
Authors: Molloy S. , Holland C. , Poole R.
Published: June 2009

A total of 549 brown trout were caught from two lakes, Lough Feeagh and Bunaveela Lake, in the Burrishoole system, Co. Mayo, Ireland. Seven species of metazoan parasite were detected but only four species occurred in ≥10% of the sample. The parasite community of the trout was dominated by a single species, Pomphorhynchus laevis, with a prevalence of 58%. Only one allogenic helminth species was recorded from the trout, Diphyllobothriurn ditremum, with the community mainly comprising autogenic species. Few differences were found between the two lakes, although the larger lake, Lough Feeagh, did contain some trout which harboured more parasite species and had, on average, fish with higher numbers of individual parasites. Measures of species richness and diversity were very low, indicating an impoverished helminth community with little potential for interspecific interactions. Host age was found to significantly influence these indices of infracommunity structure.
The genetic relationships betweenEchinostoma caproni, E. paraensei, andE. trivolvisas determined by electrophoresis
Authors: Sloss B. , Meece J. , Romano M. , Nollen P.
Published: June 2009

Adults ofEchinostoma caproni, F. paraensei, andE. trivolviswere processed for starchgel electrophoresis. Ten enzyme systems representing 12 structural loci were examined using three different buffer systems.E. paraenseiandE. caproniwere found to be genetically inbred as indicated by the lack of heterozygosity in individual worms. All three taxa showed fixed differences indicating they are distinct species. Fixed differences were found betweenE. paraenseiandE. caproniin six enzyme systems, betweenE. paraenseiandE. trivolvisin five enzyme systems, and betweenE. trivolvisandE. caproniin five enzyme systems. Phenic relationships among the three species showedE. caproniwas genetically more similar toE. trivolvisthan toE. paraensei.
Prevalence of microfilaraemia in episodic weakness and clinically normal dogs belonging to hunting breeds
Authors: Papazahariadou M.G. , Koutinas A.F. , Rallis T.S. , Haralabidis S.T.
Published: June 2009

Blood samples from 50 dogs with episodic weakness and 50 clinically normal dogs, all belonging to hunting breeds, were examined for microfilariae using the modified Knott's method. The prevalence of microfilaraemia in dogs belonging to the episodic weakness group was 10% forDirofilaria immitis, 30% forDirolfilaria repensand 8% forAcanthocheilonema reconditum. In the clinically normal group, the figures were 14% forDirofilaria repensand 4% forAcanthocheilonema reconditum. The overall percentage of dogs with microfilaraemia in the episodic weakness group was 44 and that of the clinically normal group 16, with a statistically significant difference (P<0.01). The prevalence of microfilaraemia due to the nonpathogenic filarial species (Dirofilaria repens, Acanthocheilonema reconditum) was 34% and 16% for the episodic weakness group and the clinically normal dogs, respectively, with no significant difference.