Division of General Biology, Institute of Biology and Environmental Protection, Teachers' Training College, ul. —o3nierska 14, 10-561 Olsztyn, Poland

Summary

The activity of trehalase was determined in musc- les isolated from the body wall of the fertilized female A. suum, divided into four sections.In the muscles from the anterior part a relatively high- er activity of trehalase was observed than in the posterior part - 25.58 ± 9.06 and 7.46 ± 7.21 u/mg of proteins, res- pectively. The highest activity of the enzyme was charac- teristic for the muscles of the ventral side of anterior part (30.78 ± 5.88 u/mg). The activity of the enzyme in the muscles of the tail (74.91 ± 3.04 u/mg) and head (52.91 ± 5.11 u/mg) was significantly higher than in the other seg- ments of the parasite body where it ranged from 24.69 ± 8.12 u/mg to 12.31± 2.78 u/mg of proteins.

The amino acid (AA) spectra of females of two nema- tode species are reported: Anguillicola crassus - (A n g u- i l l i c o l i d a e), from the host Anguilla anguilla and Philometra ovata - (P h i l o m e t r i d a e), from the host Abramis brama. Seventeen AA, of these 11 essential AA (EAA) and 6 non-essential AA (NEAA) were determined. Differences in quantitative values of AA in the nematode species compared (A. crassus : Ph. ovata) are statistically signifi- cant in 9 EAA and 4 NEAA. In the EAA set of A. cras- sus the highest values are in methionine, valine and tyro- sine, in that of Ph. ovata in arginine, leucine and valine. In the Neaa set of both species, the highest values were indicated by glutamic acid and aspartic acid. Differences between both nematode species were found in proline, alanine, glycine and serine (in respective hierarchic quantitative order). In the species A. crassus the AA spectrum was examined in 3 groups. The first sample (ACE) consisted of females in beginning maturation pha- se, the second sample (ACL) consisted of fully mature fe- males with embryonated eggs and fully developed shea- thed larvae. The third sample (ACT) consisted of both growing phases in nematodes (ACE + ACL). The compa- rison of the analysis results between ACE and ACL revealed statistically significant differences in the quan- titative values in 13 AA.

Parasitological Institute SAS, Hlinkova 3, 040 01 Kosice, Slovak Republic; *Department of Biology, University of Ferrara, Via L. Borsari, 46-44100, Italy

Summary

In vivo efficacy of subcurative doses of praziquantel (PZQ) and liposome - incorporated PZQ against tetra- thyridia Mesocestoides corti (syn. M. vogae) in the liver and the peritoneal cavity was evaluated within two weeks after the last dose. In the onset of the experiments, effects of both drug formulations on the surface morphology and motility of larvae were also studied using scanning elect- ron microscopy (SEM) and motility apparatus. Entrap- ment of the same concentration of PZQ in liposomes modified effects of drug itsef and differences were found mainly in the intensity and time-occurence of changes. Present data indicate the prolonged circulation time of unmetabolized PZQ when given to mice in liposomes, at least for several days after intraperitoneal administration. Moreover, stronger impact of liposomized PZQ on the motility and structural changes of tegument implies the synergistic action of lipoid carrier for potentiation of the anthelmintic capacity of PZQ itself.

Parasitological Institute SAS, Hlinkova 3, 040 01 Kosice, Slovak Republic

The paper presents the epidemiological findings in children infected for the first time at the age of 1—5 years. The children were repeatedly hospitalized with re- current clinical toxocarosis, confirmed by the presence of high (1:1600) to very high (1:3200) titers of anti-Toxo- cara IgG antibodies. Within 72 months since the first infection 14 relapses occurred in the patients studied. The blood count of most of them showed the presence of eosinophilia and spora- dically of leucocytosis for as long as 36 months since the first infection. The reduced level of haemoglobin persis- ted for 48 months and high titers of anti-Toxocara IgG antibodies for as long as 72 months post the first infec- tion. Of total immunoglobulins, IgG were elevated in 50 % of children as early as on their infection and this eleva- tion endured. IgA were increased in 28.6 % only with the first infection, IgM in 85.7 % with the infection and the first relapse and in all cases with the 2nd and 3rd recur- rence. The highest elevation was observed in total IgE immunoglobulins. Children coming from dog- or cat- keeping or puppy-breeding families are at the greatest risk of recurrent larval toxocarosis.

Some epidemiological and clinical observations on hu- man trichinellosis in Henan province, China were car- ried out from January 1992 to December 1996. The re- sults showed that 467 patients came from 12 adminis- trative areas and cities of the province itself, and acquired the infection mainly by eating undercooked dumplings, tasting the raw pork filling for dumplings, ingesting scal- ded pork or mutton. There was a high incidence season of trichinellosis in winter. Most of the patients were wor- kers, cadres and merchants aged 20—49 years, and the incidence was higher in males than in females. The main clinical manifestations of trichinellosis were fever of long duration, general myalgia, muscle tiredness and eosino- philia.  The results of this study emphasize the increasing important role played by the consumption of herbivorous animal meat as a source of human infection and the ne- cessity for health education and for the inspection of meat for Trichinella larvae in China.

Section of Parasitology, Department of Zoology and Fishery, Czech University of Agriculture, Prague, Czech Republic

The experiment was conducted in thoroughbred studs near Prague. Faecal nematode egg count and larval cultures from herd of horses were realized. All animals from herds were coproscopically examined monthly. The infections observed were S t r o n g y l i d a e (60.5 %), Strongylinae (8.15 %), Triodontophorus spp. (5.17 %), Strongylus vulgaris (2.49 %), S. equinus (0.05 %), S. edentatus (1.88 %), Parascaris equorum (2.91 %), Stron- gyloides westeri (1.88 %), Habronema spp. (0.73 %). The prevalence and egg (larval) count maxima of the ne- matodes were observed. The first seasonal peak occurren- ce of strongylid infection appeared at the start of spring (February, March) and the second in the autumn (Sep- tember). The strongyle eggs were found in all groups. No dif- ferences were noted between strongylid egg counts in horses with and without an access to the pastures. The highest prevalence was observed in saddle horses for children. Strongylus spp. occurred more frequently in horses without an access to the pastures. The egg counts indicated that Parascaris equorum contributed appreciab- ly to eggs in the faeces of horses to two years of age, the highest prevalence of Strongyloides westeri occurred in faeces of yearlings and stud horses. Infection of Habro- nema spp. showed gradual accumulation of these nema- todes only in horses with an access to the pastures.

Communities of free-living and plant parasitic nema- todes were studied in some forest nurseries of different regions of the Slovak Republic. 89 nematode species, members of all trophic groups, were found altogether. A total of 18 species of plant parasitic nematodes were iden- tified in all the localities. Predominating species were Helicotylenchus digonicus, Malenchus exiguus, Paraty- lenchus goodeyi, Rotylenchus fallorobustus, Rotylenchus robustus and Bitylenchus dubius. The structure of trophic groups, and also percentage occurrence of parasitic ne- matodes varied with individual region. Omniphages pre- dominated in most of the regions studied.