A modified two-step method for cryopreservation of mouse embryos for purposes of embryo banking.

So far, more than 17,000 embryos have been frozen in the repository of the cryobank in the Institute of Molecular Genetics. The freezing of embryos from more than 20 inbred, congenic and mutant strains has been completed. For purposes of embryo banking, a modified two-step method was used. The first step includes slow freezing, after seeding, to -25 degrees C, rate 0.3 degrees C/min, and is followed by a second step involving direct transfer of the embryos into liquid nitrogen. A relatively high percentage of survival is found (85-95%) after thawing, depending on the strain used. If thawed embryos are cultivated briefly and transferred into recipients, 20-35% living offspring are obtained. Mice born after embryo transfer are subjected to genetic control in order to check the correct procedure of embryo banking.

Two new coccidians from passeriform birds.

A description is given of two new coccidians, Caryospora jiroveci sp.n. from Erithacus rubecula and Eimeria depuytoraci sp.n. from Sylvia curruca. This is the second finding of a Caryospora species from passeriform birds and the first finding of an Eimeria species from sylviids.

Sarcocystosis in cattle and sheep at Prague abattoir.

A total of 288 animal oesophagi, including 154 from cattle and 134 from sheep of various age, were examined for the presence of sarcosporidians at Prague abattoir. The material from cattle was positive in 129 cases (84%) and all the three species of sarcosporidians hitherto described from cattle were identified: Sarcocystis cruzi, S. hirsuta and S. hominis. Among the sheep, 110 animals (82%) were infected. The macroscopic species S. tenella was found in 23 cases. The remaining positive findings were cystozoites and microscopic cysts of Sarcocystis including S. ovicanis (in 19 cases).

Muscle Sarcocystosis in pheasants and first records of the genus Sarcocystis in Phasianus colchicus Linné, 1758 in Czechoslovakia.

During examination of 41 pheasants from the vicinity of Jindrichuv Hradec (South Bohemia) muscle sarcocystosis was found in 15 birds (i.e., in 36.5%). There were two types of sarcosporidia. Type I was recorded in 3 pheasants and possessed small cystozoites measuring 6 x 2 micrometers. There occurred also stages measuring 3-4 x 2 micrometers corresponding in their morphology to merozoites of the pre-cystic phase of reproduction. Type II was found in 12 birds and possessed large, lancet-shaped cystozoites measuring 16 x 2-3 micrometers. Type II conforms to the description of Sarcocystis sp. by Wenzel et al. (1982), whereas type I seems to represent a new species of sarcosporidia.

Contribution to the serological diagnosis of sarcocystosis.

The importance of the IFA-test (Indirect Fluorescent Antibody Test) in the diagnosis of sarcocystosis in the intermediate host has been confirmed in the present paper. We assessed the time of the first appearance of serum antibodies in the intermediate host in mice inoculated experimentally with the species Sarcocystis dispersa. By means of the IFA-test, the first antibodies were found on day 20 p.i. Cross-reactions among antisera of S. dispersa and a heterologous antigen of S. cernae disclosed that the reaction was not species-specific, but genus-specific. In addition, we confirmed serologically that the antigenic structure of the genus Frenkelia was identical to that of the genus Sarcocystis, because the results of cross reactions obtained with the IFA-test were identical.

Indirect haemagglutination reaction with Sarcocystis dispersa antigen.

A description is given of the preparation of antigen from Sarcocystis dispersa cystozoites and the procedure of the indirect haemagglutination test (IHA). The antibodies against this antigen were detected in experimentally infected mice from day 20 p.i. (1: 640). In the following weeks the antibody titres reached the value of 1: 40,960. The sera of pigs, sheep and horses spontaneously infected with other Sarcocystis species reacted with this antigen in low titres only. The bovine sera gave negative reactions even in cases when Sarcocystis cysts were present in the muscles of the examined animals. A possible application of IHA for the research and diagnostic purposes is discussed.

Contribution to the problem of cyst-producing coccidians.

The problem of life cycles of cyst-producing coccidians, mainly those of the genus Sarcocystis, from carnivorous birds has been discussed. Oocysts of the "sarcocystic" type have been recovered from 9 species of birds of prey and owls from Czechoslovakia. The course of experimental infection in a group of birds consisting of the species Tyto alba, Asio otus, Strix aluco, Buteo buteo has been described. We inoculated these birds with cystic stages of the genus Sarcocystis obtained from white laboratory mice (Mus musculus) infected previously with oocysts from Tyto alba. The nomenclature of heteroxenous coccidians of the genus Sarcocystis has been discussed and suggestions have been made for the use of simple, one-word specific names. A description is given of a new species of the genus Sarcocystis--Sarcocystis dispersa sp. n. Its asexual development and cyst production in Mus musculus (intermediate host), and cyst production in Tyto alba and Asio otus (definitive hosts) have been studied.

Spontaneous and experimental infection of domestic rabbits by Sarcocystis cuniculi Brumpt, 1913.

In 43 animals, representing 36% of a sample of 117 domestic rabbits, antibodies to Sarcocystis were detected using indirect immunofluorescent antibody test (IFAT). Experimental transmission of the parasite from rabbit to cat and back to rabbit proved that the organism involved was Sarcocystis cuniculi Brumpt, 1913. The antibody response in experimental transmission was revealed by IFAT: the level of antibodies was generally low and the antibodies disappeared in less than 100 days p.i., while the parasites still remained viable in host's muscle tissue. The diagnosis of rabbit sarcosporidiosis in the definitive and intermediate hosts is discussed.

[Hypergastrinemia associated with Helicobacter pylori infection and sideropenic anemia in a 15-year-old girl]. / Hypergastrinémie spojená s infekcí Helicobacter pylori a sideropenickou anémií u patnáctileté dívky.

H. pylori is a major cause of primary chronic gastritis and peptic ulcer disease in children. The authors give an account of H. pylori infection (cagA+, vacA+) in a 15-year-old girl where the initial clinical features included fatigue, collapses, and anorexia, elevated serum gastrin level (> 1000 mIU/l) raised the suspicion of gastrinoma. H. pylori gastric infection was also associated with iron-deficiency anemia. After treatment for H. pylori infection (omeprazole, clarithromycin, amoxycillin), clinical symptoms improved consistently, the serum gastrin level was repeteadly quite normal and hematologic and iron profiles were within the normal range. There is compelling evidence that H. pylori must be taken into account as a cause of hypergastrinemia other than gastrinoma in childhood.

[Improved results in children with acute lymphoblastic leukemia treated with the ALL-BFM 90 protocol in the Czech Republic]. / Zlepsení výsledku lécby detí s akutní lymfoblastickou leukémií podle protokolu ALL-BFM 90 v Ceské republice.

BACKGROUND: Prognosis of children with acute lymphoblastic leukaemia (ALL)--the most common cancer in childhood, has improved remarkably over the last 40 years. The authors report the treatment outcome in children with ALL cured according to ALL-BFM 90 Study protocol in the Czech Republic during the first half of nineties. METHODS AND RESULTS: Children aged 0-18 years were included into the study in 10 centers between 1990 to 1996. Patients were classified into standard-risk (SR), medium-risk (MR) and high-risk (HR) group according to initial leukaemic burden, early treatment response, and genotype of leukaemia. Duration of the chemotherapy was two years. Treatment results were evaluated in 352 children. With a median follow-up of 7.3 years, event-free-survival (EFS) was 71.3% and overall survival 76.4%. EFS was 80.3%, 74% and 28.2% in SR, MR and HR group, respectively. Relapse was diagnosed in 17.8% of the patients. CONCLUSIONS: The treatment outcome of children with ALL improved significantly (p = 0.0045) compared to the previous study ALL-BFM 83 (EFS 62%). These results are comparable to those achieved by leading leukaemia study groups in the world.

[Consolidation of therapy of acute myeloid leukemia with the AML-BFM 93 protocol in children in the Czech Republic]. / Sjednocení lécby detí s akutní myeloidní leukémií v Ceské republice podle protokolu AML-BFM 93.

BACKGROUND: Acute myeloid leukemia (AML) in children is rare. Although more resistant to chemotherapy than acute lymphoblastic leukemia, its responsiveness and survival rates have considerably improved during the last 15 years by virtue of intensification of chemotherapy and due to the better supportive care. Relapses still remain the main cause of treatment failure. Management of children with AML was unified in the Czech Republic in 1993 according to AML-BFM 93 Study protocol. METHODS AND RESULTS: Treatment results were evaluated in 61 patients, of whom 45 (73.8%) achieved complete remission. Five-year event-free-survival (EFS) was found in 42.3%, and overall survival was 45.3%. Prognosis of the standard-risk patients was significantly better than in the high-risk group (EFS 62.5% vs. 29.7%, p = 0.03). The most important prognostic factor was the early treatment response. Compared to chemotherapy, allogeneic stem-cell transplantation did not significantly improve the outcome of high-risk patients. CONCLUSIONS: Treatment results of children with AML in the Czech Republic are comparable to those achieved by leading leukemia study groups in the world. The aim of the next study is to increase the complete-remission rate by reducing early deaths.