bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abnormal patterns of embryogenesis inDirofilaria immitistreated with ivermectin
Authors: Lok J. B. , Harpaz T. , Knight D. H. 
Published: June 2009

ABSTRACTThe 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

AbstractThe 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

ABSTRACTGerbils 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

ABSTRACTPreviously 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

ABSTRACTEggs (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

ABSTRACTIt 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

ABSTRACTThe 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

ABSTRACTParasitism 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

ABSTRACTThe 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

ABSTRACTTo 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

ABSTRACTCooperia 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

ABSTRACTEnzyme 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

ABSTRACTA 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

ABSTRACTPharmacological 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

ABSTRACTExcretory/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

AbstractThree 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

AbstractThe 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

AbstractA 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

AbstractThe 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

AbstractLaboratory 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

AbstractThe 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.