Egg rejection behaviour, as an antiparasite defence against brood parasitism was compared in two great reed warbler Acrocephalus arundinaceus populations. In central Hungary the host population lives in sympatry with the common cuckoo Cuculus canorus, and it is heavily parasitised (ca 66%). In central Greece the great reed warbler occurs in allopatry with the cuckoo, so it is not parasitised at all. Experimental parasitism with poorly mimetic (often called 'non-mimetic') artificial cuckoo eggs revealed a 100% rejection rate towards the foreign eggs in the Greek population, but the Hungarian hosts accepted 29.4% and rejected 70.6% of the model cuckoo eggs. No other rejection type than ejection was observed. The significantly higher level of rejection in Greece than in Hungary suggests that the Greek great reed warbler population is an abandoned host population of the cuckoo, which kept its egg recognition ability. A computer-based image analysis of host's clutches revealed that interclutch variation in egg colour was greater than intraclutch variation in the Hungarian population, but not in the Greek population. Spottedness of eggs were similar in both populations. Generally, a tendency for a higher interclutch variation was found in Hungary. Intraclutch variation was more similar in the two populations, but for the colour variables it showed a lower value in Hungary than in Greece. The heavy cuckoo parasitism in Hungary is suggested to be the main cause for the increased interclutch variation in relation to intraclutch variation in egg appearance among great reed warbler clutches. The high interclutch variation reduces the chance that the parasite egg's appearance matches that of the hosts', which facilitates hosts' egg discrimination.

Specific gene and miRNA expression patterns are potential early biomarkers of harmful environmental carcinogen exposures. The aim of our research was to develop an assay panel by using several miRNAs for the rapid screening of potential carcinogens. The expression changes of miR-124-1, miR-212, miR-132, miR-134, and miR-155 were examined in the spleen, liver, and kidneys of CBA/Ca mice, following the 20 mg/bwkg intraperitoneal 7,12-dimethylbenz(a)anthracene (DMBA) treatment. After 24 h RNA was isolated, the miRNA expressions were analyzed by a real-time polymerase chain reaction and compared to a non-treated control. DMBA induced significant changes in the expression of miR-134, miR-132, and miR-124-1 in all examined organs in female mice. Thus, miR-134, miR-132, and miR-124-1 were found to be suitable biomarkers for the rapid screening of potential chemical carcinogens and presumably to monitor the protective effects of chemopreventive agents.

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Polyphenols are capable of decreasing cancer risk. We examined the chemopreventive effects of a green tea (Camellia sinensis) extract, polyphenol extract (a mixture of blackberry (Rubus fruticosus), blackcurrants (Ribes nigrum), and added resveratrol phytoalexin), Chinese bayberry (Myrica rubra) extract, and a coffee (Coffea arabica) extract on 7,12-dimethylbenz[a]anthracene (DMBA) carcinogen-increased miR-134, miR-132, miR-124-1, miR-9-3, and mTOR gene expressions in the liver, spleen, and kidneys of CBA/Ca mice. The elevation was quenched significantly in the organs, except for miR-132 in the liver of the Chinese bayberry extract-consuming group, and miR-132 in the kidneys of the polyphenol-fed group. In the coffee extract-consuming group, only miR-9-3 and mTOR decreased significantly in the liver; also, miR-134 decreased significantly in the spleen, and, additionally, miR-124-1 decreased significantly in the kidney. Our results are supported by literature data, particularly the DMBA generated ROS-induced inflammatory and proliferative signal transducers, such as TNF, IL1, IL6, and NF-κB; as well as oncogenes, namely RAS and MYC. The examined chemopreventive agents, besides the obvious antioxidant and anti-inflammatory effects, mainly blocked the mentioned DMBA-activated factors and the mitogen-activated protein kinase (MAPK) as well, and, at the same time, induced PTEN as well as SIRT tumor suppressor genes.

To determine the cotton bollworm migrating population rate in Hungary, we examined the weights and the front wing morphological feautures of trapped moths. We used sex pheromone traps to monitor field populations during the maize vegetation cycle period in 2008. We examined moths trapped at various times, and measured their body mass (m) and morphological features, namely the front wing quotient (fWQ = quotient of length of front wing/width of front wing), modified wing loading (WL = weight of moth/surface of front wing), and the relative thorax size (RTS = width of thorax/width of head). The data were analysed by Student t-test, anterior wing abrasion and darkness were analysed by a Adobe Photoshop 7.0 software. The Hungarian appearance of three cottom bollworm generations in 2008 was also observed. Based on the examined morphological features we found regularity in body mass, front wing quotient and modified wing loading changes during the flight period. The specimens trapped in the first and third part of the flight period had lower body mass, larger wing surface, longer wings and more favourable modified wing loading than the specimens trapped in the middle of the flight period. The abrasion and colour of the anterior wings of cotton bollworms were concordant to morphometric investigations. The abrasion in darker spots E1 and E3 clearly showed a more intensive usage of the wings in case of specimens trapped at the beginning and at the end of the flight period.

DNA methylation is an epigenetic mechanism that is crucial for mammalian development and genomic stability. Aberrant DNA methylation changes have been detected not only in malignant tumor tissues; the decrease of global DNA methylation levels is also characteristic for aging. The consumption of extra virgin olive oil (EVOO) as part of a balanced diet shows preventive effects against age-related diseases and cancer. On the other hand, consuming trans fatty acids (TFA) increases the risk of cardiovascular diseases as well as cancer. The aim of the study was to investigate the LINE-1 retrotransposon (L1-RTP) DNA methylation pattern in liver, kidney, and spleen of mice as a marker of genetic instability. For that, mice were fed with EVOO or TFA and were pretreated with environmental carcinogen 7,12-dimethylbenz[a]anthracene (DMBA)—a harmful substance known to cause L1-RTP DNA hypomethylation. Our results show that DMBA and its combination with TFA caused significant L1-RTP DNA hypomethylation compared to the control group via inhibition of DNA methyltransferase (DNMT) enzymes. EVOO had the opposite effect by significantly decreasing DMBA and DMBA + TFA-induced hypomethylation, thereby counteracting their effects.

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