bluuebunny/crossref_metadata_2025_split huggingface dataset:
Schistosoma rodhaini: dynamics and cercarial production for mono- and pluri-miracidial infections of Biomphalaria glabrata
Authors: Touassem R. , Théron A. 
Published: June 2009

ABSTRACTNo significant difference in cercarial production was noted when Biomphalaria glabrata from Brazil were exposed to one or several miracidia of Schistosoma rodhaini from Burundi, even though the dynamics seemed different. The minor differences can be explained by the intramolluscal larval development of this parasite characterized by the production of a high number of daughter sporocysts over a long period.
The ecology of infective larvae of bovine gastrointestinal trichostrongylids in dry season contaminated pastures in the Nigerian derived savanna
Authors: Chiejina S. N. , Fakae B. B. 
Published: June 2009

ABSTRACTFive experimental grass paddocks were sequentially contaminated with fresh bovine faeces containing known numbers of eggs of predominantly Haemonchus and Cooperia spp. during the 1984/85 dry season (November to March). Faecal, herbage and soil samples were examined at regular intervals between November and June in order to determine the rate of development and mortality of infective larvae (L3) in faeces, the pattern of herbage infestation with L3 and the role of faeces and soil as reservoirs of L3 during the dry season and early rains. L3 first appeared in faeces approximately 4 days post contamination (PC) and peak counts were obtained 28, 14, 7 and 14 days PC in the paddocks contaminated in December, January, February and March, respectively. The counts initially declined linearly at the rate of approximately 7535 L3/week and 10 947 L3/week in P2 and P4 respectively, due primarily to mortality but later there was an accelerated fall in the counts as the surviving L3 moved out of the faecal pads onto herbage. The overall trend of faecal larval populations in each paddock was therefore distinctly curvilinear. Although large numbers of L3 were present inside dry faecal pads in most paddocks throughout the dry season, none migrated on to herbage at that time of the year. Translation of L3 to herbage was very rapid and occurred simultaneously in all the paddocks 24 hours following the first heavy rainfall in late March. Consequently peak herbage infestations in all paddocks were coincident and occurred a few days after commencement of larval migration. The closer to the end of the dry season the contaminations were carried out, the larger were the subsequent early rains rise and the peak herbage infestation and the longer this infestation survived on herbage. No L3 were recovered from soil throughout the study, which suggests that faecal pads were the sole reservoir of L3 during the dry season and hence the source of the early rains herbage infestation.
Enzyme polymorphism in Schistosoma mattheei from cattle in the Eastern Transvaal Lowveld
Authors: Kruger F. J. 
Published: June 2009

ABSTRACTEnzyme electrophoresis was conducted on 10 Schistosoma mattheei adult worm samples, comprising 270 individuals, collected from cattle in the Eastern Transvaal Lowveld. Glucose-6-phosphate dehydrogenase (G6PDH) was studied in all the samples and phosphoglucomutase (PGM) and malate dehydrogenase (MDH) in five populations each. Only one population was polymorphic for G6PDH. In this population, in addition to the allele found in all the other samples, a second allele occurred with a similar Rf value to S. haematobium. The two alleles were in Hardy-Weinberg equilibrium. MDH-1 exhibited two alleles. However, these alleles were not in equilibrium. In certain populations, heterozygotes occurred together with homozygotes of one of the alleles only. PGM was monomorphic in all the populations studied.
Pathological effects of Echinostoma caproni (Trematoda) in the domestic chick
Authors: Kim Stuart , Fried Bernard 
Published: June 2009

ABSTRACTDomestic chicks experimentally infected with Echinostoma caproni for 2 weeks showed a dilated ileum, unkempt feathers, watery diarrhoea, and weight loss. The ileum from infected and control chicks was fixed in 10% neutral buffered formalin, and prepared as 10 μm paraffin sections stained in haematoxylin and eosin, Papanicolau, periodic acid-Schiff, picro-ponceau, and alcian blue. The infected ileum showed atrophic villi, hypertrophied circular musculature with collagen-like fibres and haemorrhagic zones. The brush borders of epithelial cells and goblet cells were absent in the mucosa of the infected ileum. Worms in contact with host mucosa showed tissue plugs in the suckers. The cephalic spines of worms abraded the host mucosa.
Further studies on the effect of cyclosporin A on the course of Paragonimus infection in rats
Authors: Hashiguchi Yoshihisa , Okamura Yoshisuke 
Published: June 2009

ABSTRACTParagonimus ohirai-infected rats were treated with cyclosporin A (CyA) at different times during the course of infection. CyA (5×80 mg/kg) affected the worm recovery, growth and maturation rates of P. ohirai with respect to control values. This tendency was most remarkable in animals treated 15 days and more after infection with CyA (groups B, +15 to +19 days; C, +25 to +29; D, +35 to +39 and E, +45 to +49). In group A (0 to +4), however, the drug did not affect markedly the growth and maturation of worms, although it significantly lowered worm recovery rates. CyA administration also affected normal migration of P. ohirai in the highly susceptible host (rat), when the drug was administered during the peritoneal and/or liver phase of infection. Thus, in this P. ohirai/rat model, CyA significantly reduced worm recovery rates, and affected the growth, maturation and migration of the worms depending on the time of administration.
A comparison of a modified quick-Kato technique and the Stoll dilution method for field examination for Opisthorchis viverrini eggs
Authors: Viyanant V. , Brockelman W. Y. , Lee P. , Ardsungnoen S. , Upatham E. S. 
Published: June 2009

ABSTRACTA modified quick-Kato technique and the Stoll dilution method for the diagnosis of Opisthorchis viverrini infection were compared from the standpoints of both replicability and sensitivity. One Stoll dilution preparation and two modified quick-Kato smears were prepared from single stool specimens collected from 221 persons in a village in north-eastern Thailand. Stool examinations were made in duplicate for each technique by two examiners, and the averages of the raw egg counts were used to estimate the intensity of infection. Statistical analyses revealed that the modified quick-Kato technique was slightly more sensitive, and thus would detect more positives, but was lacking in replicability and hence less suitable for measurement of individual intensity of infection. We therefore recommend the Stoll dilution technique for field surveys and measurement of individual intensity of 0. viverrini infection.
Histochemical studies on eggshell formation in Paramphistomum cervi (Digenea: Paramphistomatidae)
Authors: Gupta B. C. , Parshad V. R. , Guraya S. S. 
Published: June 2009

ABSTRACTThe formation of the egg mass in the ootype, containing the oocyte, vitelline cells, numerous spermatozoa and Mehlis’ gland secretion marks the beginning of eggshell formation. Mehlis’ gland cells pour their lipoprotein secretion into the ootype; this secretion forms a thin template around the egg mass and upon this template the shell globules are deposited. Eggshell formation begins in the proximal uterus and is completed in the middle uterus. The eggshells are devoid of phenols and phenolase indicating that hardening is not by quinone tanning. The eggshells contain keratin and are stabilized by disulphide linkages.
The effect of light and darkness on the production of cercariae of Schistosoma haematobium from Bulinus globosus
Authors: Raymond K. M. , Probert A. J. 
Published: June 2009

ABSTRACTThe cercariae of Schistosoma haematobium showed a diurnal periodicity of emergence from Bulinus globosus in a twelve hour light/dark cycle. Peak emission occurred at 11.00 hrs with a smaller peak at 20.00 hrs, following the start of the period of darkness. In continuous illumination this second peak was not seen, indicating that only the morning peak is circadian in origin. The evening peak occurs in response to dark treatment and can be produced by periods of darkness ranging from eight seconds to one hour. The longer the period of dark treatment the longer the rise in output is maintained on return to light conditions. Subjection of snails to periods of dark treatment during the normal light period caused a reduction in the evening peak with the largest effect seen following the longest period of darkness. An increased output of cercariae was seen following fifteen minutes exposure to a range of light intensities, the largest increase occurring at 10 000 and 7000 lux and complete darkness. The rapidity of this reaction to variations in light intensity suggests that the cercariae of S. haematobium are showing emergence in response to shadows.
Hymenolepis citelli, H. diminutaandH. microstoma: immunoglobulin-containing cells in the lamina propria of the mouse gut during primary and secondary infections
Authors: Alghali Sidi T. O. 
Published: June 2009

ABSTRACTThe indirect immunofluorescent technique was used to determine the occurrence of IgA, IgM and IgG1immunoglobulin-containing cells in local intestinal mucosal immune responses toHymenolepis citelli, H. diminutaandH. microstomainfections in mice. In the intestinal lamina propria ofH. citelliandH. diminutainfected mice there was no increase in the mean numbers of immunoglobulin-containing cells when compared with uninfected control mice, but there was inH. microstomainfected mice. The numbers of IgG1– positive cells in both infected and uninfected mice were very small relative to IgA and IgM immunocytes. The distribution of immunocytes in the lamina propria of infected and uninfected mice was essentially similar and the localization of isotypes in duodenal sections showed no immunoglobulins in the villous epithelial cells. There was also no marked difference between primary and secondary infections indicating that immunoglobulin-containing cells play no major role in functional immunity against hymenolepid infections in the mouse. The presence of IgA and IgM was also demonstrated on the tegument of the tapeworms, although the distribution was patchy and more abundant onH. microstomathan onH. diminutaorH. citelli. The time of appearance of both isotypes was latest onH. citelli.
Periodicity of Dirofilaria immitis microfilariae in a dog from Muheza district, Tanzania
Authors: Matola Y. G. 
Published: June 2009

ABSTRACTDirofilaria immitis (the dog heartworm) microfilarial periodicity was determined hourly for five days in an infected dog from Kambai village in Muheza district Tanzania. Maximal microfilarial counts were found at 1100 h and minimal at 2200 h. This finding represents the first record of D. immitis microfilarial periodicity in Tanzania.
Glucose 6-phosphate dehydrogenase: isoenzymatic pattern in Oesophagostomum venulosum, Trichuris ovis and T. suis
Authors: Rodriguez B. , Cutillas C. , German P. , Guevara D. 
Published: June 2009

ABSTRACTIn the present communication we have studied the isoenzymatic pattern activity of the glucose 6-phosphate dehydrogenase (G6PD) in Oesophagostomum venulosum, Trichuris ovis and T. suis, parasites of Capra hircus (goat), Ovis aries (sheep) and Sus scrofa domestica (pig) respectively, by polyacrylamide gel electrophoresis. Different phenotypes have been observed in the G6PD isoenzymatic pattern activity in males and females of Oesophagostomum venulosum. Furthermore, G6PD activity has been assayed in Trichuris ovis collected from Ovis aries and Capra hircus. No differences have been observed in the isoenzymatic patterns attending to the different hosts. All the individuals exhibited one single band or two bands; this suggests a monomeric condition for G6PD in T. ovis. In T. suis the enzyme G6PD appeared as a single electrophoretic band in about 85·7% of the individuals.
Determination of the minimum time of praziquantel therapy required for the in vitro treatment of protoscoleces of Echinococcus granulosus
Authors: Morris D. L. , Taylor D. H. , Daniels D. , Riley E. M. , Richards K. S. 
Published: June 2009

ABSTRACTOvine and equine protoscoleces of Echinococcus granulosus were cultured for 26 days with our without praziquantel and viability assessed, by eosin exclusion, for cultures in various drug concentrations (50, 250 and 500 μg/l) and periods of exposure (1, 3 or 7 days (d)) before removing/‘rescuing’ to drug-free medium. Drug efficacy was proportional to drug concentration and to length of exposure. At higher drug concentrations shorter exposures were required to produce the effect of continuous drug treatment, 1d therapy at 500 μg/l killing 96% ovine protoscoleces by day 14 whereas 7d therapy at 50 μg/l was required to produce a similar effect. Equine protoscoleces appeared marginally less susceptible than those of ovine origin. The relevance of the results in the need for peri-operative prophylaxis against spilled protoscoleces in man is discussed.
Immunization of chicks at various ages with irradiated infective eggs of Ascaridia galli
Authors: Malviya H. C. , Varma T. K. , Dwivedi P. 
Published: June 2009

ABSTRACTThe possibility of safe immunization of chicks at an appropriate age with a double-dose irradiated Ascaridia galli vaccine given orally at two weeks interval was explored. Chicks immunized at 7 or 10 days of age were not affected adversely since they did not develop any clinical signs and there was no worm establishment after challenge infection. Immunization also elicited detectable circulating antibody titres, with IHA and the conglutinating complement absorption test having a tendency to be enhanced after the booster dose.
The occurrence ofRhabditis (Rhabditella) axeiin the faeces of a chicken in Egypt
Authors: El-Azazy O. M. E. , El-Gawady H. M. , Nada M. S. 
Published: June 2009

ABSTRACTRhabditis axei, the free living nematode, was detected in the faeces of a chicken maintained in a clean cage in the parasitology laboratory, Zagazig University, Egypt. The source of these worms and the method of their transmission to the laboratory was discussed. The experimental inoculation of 3 chickens withR. axeidemonstrated that their survival after passing through the intestine was not possible. Free living nematodes could be confused easily withStrongyloidessp. during routine faecal examination.
A technique for skin application of exact doses ofNippostrongylus brasiliensisto rats
Authors: Tindall N. R. , Wilson P. A. G. 
Published: June 2009

ABSTRACTConventional methods for percutaneous infection of rats using third-stage juveniles ofNippostrongylus brasiliensiswhich have been artificially stimulated to exsheath lead to highly variable, and relatively poor, establishment in the intestine. A new system has been developed in which larvae applied to the skin still remain partially sheathed, as they would be in nature. Cultures of the freeliving stages of the parasite contain an annulus of clear, colourless polythene film to which some of the third-stage juveniles attach. Rats are infected with an individually counted, exact dose applied to the skin on polythene. Using this technique (‘EDT20Nb’), consistently high values for the mean proportion of the dose that becomes establishedhave been obtained, along with a variance well below the normally accepted level (from a total of 73 rats in 12 separate assays). In particular, the added component of variance between assays in this study was insignificant, so that the probability of quantitative agreement in replicate experiments based on the method is high. It is recommended for an experimental design in which small numbers of parasites can be used.
The anthelmintic activity of a novel organic arsenical, R7/45, upon Brugia pahangi in Meriones unguiculatus
Authors: Denham D. A. , Midwinter I. T. C. , Friedheim E. A. H. 
Published: June 2009

ABSTRACTThe new organic arsenical R7/45 is a rapidly acting and very potent anthelmintic against adult Brugia pahangi in jirds. Against adult worms implanted into the peritoneal cavity 5 subcutaneous (SC) injections at 2·5 mg/kg of R7/45 killed 100% of adult worms. A single dose SC of 20 mg/kg was 100% effective and 10 mg/kg 76% effective against adult worms. When jirds were autopsied at different times after treatment at 20 mg/kg SC 89% of worms were dead within three days. R7/45 was not active when given by stomach intubation. Pretreatment of jirds with R7/45 had no effect on adult worms subsequently implanted into jirds. R7/45 was highly active against third and fourth stage larvae of B. pahangi in jirds.
Chromosome C-banding techniques in Dictyocaulus filaria (Rudolphi, 1809) Railliet and Henry, 1907
Authors: Cutillas C. , Ariza C. , Guevara D. C. , Campano L. 
Published: June 2009

ABSTRACTC-banding has been performed on Dictyocaulus filaria using both original and modified techniques. The karyotype is reported based on C band observations. The existence of large heterochromatic blocks appears to be the cause of the low chiasmata frequency.
Possible direct effect of diethylcarbamazine on the infective larvae of Brugia pahangi
Authors: Fujimaki Yasunori , Shimada Masaaki , Mitsui Yoshinori , Kimura Eisaku , Aoki Yoshiki 
Published: June 2009

ABSTRACTThe direct action of diethylcarbamazine (DEC) on the infective larvae of Brugia pahangi was studied. The larvae were cultured in RPMI 1640 supplemented with foetal bovine serum and antibiotics for 22 days. Most of the larvae remained alive for 8 days, but survival rate of larvae decreased rapidly from day 10 onwards. The larvae did not grow in the culture system. The addition of DEC did not affect the morbidity of the larvae and no difference was observed in the morphological characteristics between the larvae cultured in the presence or absence of DEC.The infective larvae were cultured in vitro for 5 days in the presence or absence of DEC, and inoculated into jirds. The animals were necropsied at intervals, and developing larvae and adult worms were recovered. When the larvae were cultured without DEC and then inoculated subcutaneously into jirds, 29.8% of the inoculum was recovered 3–15 days, and 25% 19–22 weeks, post-inoculation. However, when the larvae were exposed to DEC in vitro and inoculated into jirds, the rate of recovery was reduced to 25% 3–15 days post-inoculation and 2% after 19–22 weeks. When the control larvae cultured in vitro were inoculated intraperitoneally into jirds, 41·3% of inoculum was recovered 3–15 days, and 42·8% 19–22 weeks, post-inoculation. Again the corresponding value for larvae exposed to DEC in vitro was reduced to 19.8% 3–15 days, and 8% 19–22 weeks, post-inoculation. It was observed that the larvae exposed to DEC in vitro were retarded in their development in jirds. These results indicate that DEC has a direct action against the infective larvae of B. pahangi.
Proteocephalus neglectus as a possible indicator of changes in the ecological balance of aquatic environments
Authors: Hanzelová V. 
Published: June 2009

ABSTRACTIn an environment seriously impaired by human interference (draining the reservoir), ecological relationships in a community of copepods and their impact on the transmission of the tapeworm Proteocephalus neglectus La Rue. 1911 were studied. The impairment of the environment resulted in changes in the species composition of the copepod community and in the increased diversity of the copepod species, as well as in a multiple inversion of the dominant and subdominant relationships of the two most numerous copepod species (Cyclops vicinus and Eudiaptomus zachariasi). The structure of the developmental stages of the copepod community, the seasonal dynamics of the number of copepods and the abundance of P. neglectus procercoids have changed. The predominant species in the copepod community and the most susceptible intermediate host of P. neglectus (C. vicinus) was not infected. The infection of copepods decreased by 95% and that of the definitive hosts (Oncorhynchus mykiss) by 97·5% compared with the index values recorded in the previous year.
The identity of Anisakis type II larvae with Anisakis physeteris confirmed by restriction fragment length polymorphism analysis of genomic DNA
Authors: Matsuura T. , Sun S. , Sugane K. 
Published: June 2009

ABSTRACTThe identity of Anisakis type II larvae with adult A. physeteris was confirmed by comparison of restriction fragment length polymorphisms (RFLPs) of 25S ribosomal DNA (rDNA). Patterns of RFLPs in larvae were almost identical with those in adult worms. Directly labelled 25S rDNA might serve as an appropriate probe with highly specific activity for examining RFLPs of larvae and adult worms.
Failure to demonstrate suppressor T cell activity in the lamina propria ofHymenolepis diminuta-infected rats
Authors: Palmas C. , Wakelin D. , Bortoletti G. , Ecca A. R. , Gabriele F. 
Published: June 2009

AbstractThe aim of this study was to examine whether there was an increase of suppressor T cells, relative to helper T cells, in the intestinal lamina propria ofHymenolepis diminuta-infected rats, a condition which might allow the parasite to survive for the life-span of the host. Lamina propria cells were isolated by enzymatic procedure. All lymphocytes were passed over nylon wool columns in order to remove B cells; then the T cells were purified by a panning technique using monoclonal anti-T cell antibodies. Changes in the mitogen-stimulated synthesis of 1gM, IgG and IgA by normal peripheral blood indicator lymphocytes, as measured by sandwich ELISA, was used as an index of help and/or suppression. No significant suppressor T cell activity was observed in the cultures, either from control or infected intestine.
Epidemiology of Toxocara vitulorum in cattle around Bursa, Turkey
Authors: Akyol Cetin Volkan 
Published: June 2009

AbstractThe prevalence of Toxocara vitulorum in cattle around Bursa, Turkey, was surveyed by faecal examination of eggs. The average infection rate among 11 towns was 5·1% in calves younger than 6-months-old, and 2·2% in all ages of animals. T. vitulorum was found to be prevalent in two different areas of Bursa. Third stage larvae were found in one milk sample and therefore galactogenic transmission was suggested. Experimental incubation of eggs showed that the optimum temperature for development was 20 to 30°C and eggs could survive under low temperature, indicating that grazing in the contaminated pasture may accelerate the transmission of eggs to cows. Mode of farming, therefore, affects the infection rate of T. vitulorum and may explain the difference in the rate between the two areas.
Development of the alimentary tract during morphogenesis of the metacercariae of Levinseniella brachysoma
Authors: Galaktionov K. V. , Malkova I.I. 
Published: June 2009

AbstractFor the first time the development of the alimentary tract of Levinseniella brachysoma metacercaria (Trematoda: Microphallidae) obtained experimentally from Gammarus oceanicus has been described. The foregut primordium in 16-day-old metacercariae is represented by a syncytial cylindrical cord, resulting from the fusion of embryonic cells. Non-fused parts of the plasma membranes of adjacent cells are revealed as gap cavities within the cord. Later (30th day post infection) the lumen of the foregut is formed as a result of both partial vacuolization of the cytoplasm and by a broadening of the gap cavities, resulting from a thinning of the cytoplasmic spaces between them. Besides the usual organelles, the foregut of the mature metacercaria (42nd day p.i.) contains dense secretory granules in the apical cytoplasm region and numerous microtubules in basal areas. The cellular gastrodermis is formed later than the foregut syncytium (on day 30 p.i.); its large cells contain well-developed Golgi complexes, RER and mitochondria. A noteable inclusion of the gastrodermal cells of mature metacercariae are spherical granules of moderate electron density measuring up to 3 μm in diameter. On the basis of an analysis of the ultrastructural data the possible functioning of the metacercarial alimentary tract is discussed.