Background: A comparison of fetal ultrasonographic biometric parameters of the head (head circumference -HC, biparietal diameter -BPD) in breech presented fetuses.Methods: Ultrasound biometry was performed in accordance with the method presented in the reference tables. In all breech presented fetuses, the HC, BPD and FL (femur length) were measured. High-risk and multiple pregnancies were excluded from the study.Results: A total of 111 ultrasonographic biometries were performed between the 31 st -38 th week of gestation. Fetuses in the breech position had a signifi cantly lower BPD compared to HC and FL. The diff erence between BPD and HC was 16.2 days (95%Cl 14.3-18.1; p = 0.001). Maternal age at delivery was 20 -36 years (average 28.1; median 28.0).Conclusions: According to our results, fetuses in the breech position have a signifi cantly lower BPD compared to HC or FL. HC and FL parameters correlate with gestational age. In cases of ultrasonographic biometric discrepancy between BPD and FL, the fetal position should be taken into account. Breech-presented fetuses have an elongated head shape and ultrasound biometrics should evaluate its circumference (HC). It is important to responsibly interpret the results so as not to stress the expecting mother with suspicions of fetal pathology.

POLÍVKOVÁ Z., LANGOVÁ M., ŠMERÁK P., BÁRTOVÁ B., BÁRTA I.: Antimutagenic effect of genistein. Czech J. Food Sci., 24: 119-126.A great variety of health benefits including the protection against breast and prostate cancers has been attributed to the soya consumption, because of the presence of soy beans isoflavones, genistein, and others. We investigated the antigenotoxic effect of genistein on the genotoxicity of three mutagens and carcinogens -aflatoxine B 1 (AFB 1 ), 2-amino-3-methylimidazo [4,5-f ]quinoline (IQ), and N-nitroso-N-methylurea (MNU), using the Ames bacterial mutagenicity test and the micronucleus test. In the Ames test on Salmonella typhimurium, a significant antimutagenic effect was determined against the indirect mutagen AFB 1 in two strains, TA98 and TA100. However, the effect on the IQ indirect mutagenicity was more pronounced in the test with TA98 than with TA100. The mutagenicity of the direct mutagen MNU was suppressed by genistein only at its highest concentration used (300 µg/plate). The protective effect of genistein against all three mutagens was proved in the micronucleus test as the treatment of mice with the combinations of genistein and mutagens resulted in a significant reduction of the number of micronuclei in comparison with the number of micronuclei induced by the individual mutagens alone.

Green tea is the second-most consumed beverage in the world (water is the first one) and has been used medicinally for centuries in Indiaand China. The active substances in the green tea are polyphenols (catechins) and flavonols which possess a potent antioxidant activity. Epigallocatechin gallate (EGCG) is one of the four major green tea catechins. Using the Ames test, micronucleus test, comet assay, chemiluminescence test, and blastic transformation test, we examined the antimutagenic effects of chemoprotective substance epigallocatechin gallate (EGCG) in the pure form on the mutagenicity induced by three reference mutagens: aflatoxin B₁ (AFB₁), 2-amino-3-methylimidazo [4,5-f] qui-noline (IQ), and N-nitroso-N-methylurea (MNU), and the effect of EGCG on the immunosuppression caused by these mutagens. Using the Ames test the dose dependent antimutagenic activity of EGCG was proved against indirect mutagens AFB₁ and IQ, but not against the direct mutagen MNU. In the micronucleus test, EGCG had antimutagenic effect upon all three mutagens. EGCG decreased the level of DNA breaks induced by AFB₁ in bone marrow cells and colon epithelium, and the level of DNA breaks induced by MNU in colon cells to the level found in control. The reparatory effect of EGCG on immunosupression induced by all three carcinogenic compounds was proved using chemiluminescence and blastic trasformation tests.  

Evidence exists from population-based and laboratory studies that some phytochemicals have protective effects against tumors or other diseases and reveal antimutagenic activity. We studied the protective effect of the plant phytoallexin resveratrol on the mutagenic activity of three mutagens, i.e. aflatoxin B₁ (AFB₁), 2-amino-3-methylimidazo[4,5-f]qui-noline (IQ) and N-nitroso-N-methylurea (MNU) using the Ames and the micronucleus tests. In the Ames test, we proved a significant antimutagenic activity only against the indirect mutagens AFB₁ and IQ, not against the direct mutagen MNU. A significant decrease of mutagenicity of all three mutagens was detected by the micronucleus test.  

A wide array of antioxidative and anti-inflammatory substances derived from edible plants have been reported to possess chemopreventive and chemoprotective activities. Among the most extensively investigated and well-defined dietary chemopreventives is curcumin. Using the Ames test and in vivo micronucleus test, chemiluminescence test, blastic transformation test, and comet assay, we examined the antimutagenic effects of the chemically identified chemoprotective substance curcumin (diferuloylmethane) in the pure form on mutagenicity induced by three reference mutagens: aflatoxin B₁ (AFB₁), 2-amino-3-metylimidazo[4,5-f]quinoline (IQ), and N-nitroso-N-metylurea (MNU), and the effect of curcumin on the immunosuppression caused by these mutagens. Curcumin in the pure form showed a clear antimutagenic and immunomodulatory activities on mutagenicity and immunosuppression induced by reference mutagens.