Biological Activity of Extracts from Differently Produced Blueberry Fruits in Inhibiting Proliferation and Inducing Apoptosis of HT-29 Cells.

For several decades, people have been searching for natural substances of plant origin that, when introduced into the diet, could strengthen immunity, have anticancer properties, and support conventional therapy. The development of agriculture with the implementation of various plant cultivation systems, apart from the economic aspect, results in the search for such cultivation conditions that would contribute to obtaining the most beneficial product for health. Therefore, the aim of our research is as follows: (a) to compare the antiproliferative activity and the ability to induce apoptosis of HT-29 cells by extracts from blueberry fruits deriving from different types of cultivation systems (conventional, organic, and biodynamic); (b) to examine whether the interaction of extracts with anticancer drugs used in the treatment of colorectal cancer is influenced by the type of cultivation, and (c) to investigate whether extracts obtained from fruits from subsequent years of cultivation retain the same biological activity. The results of our study are promising but inconclusive. A statistically significant difference occurred in only one of the two years of the study. The greatest inhibition of proliferation is observed for biodynamic cultivation compared to organic cultivation, while the highest levels of apoptosis and necrosis of HT-29 cells are induced by blueberry fruit extracts obtained from organic cultivation. The complementary effect of the extracts on the inhibition of HT-29 cell proliferation by anticancer drugs (5-FU and Erbitux) is not demonstrated. The induction of apoptosis by 5-FU is not enhanced by blueberry extracts, in contrast to necrosis. The level of apoptosis and necrosis induced by Erbitux is potentiated, but no dependence on crop type is shown. Blueberry fruit extracts from two consecutive years of cultivation did not maintain the same activity. A plausible reason for the variability in the composition and biological activity of fruit extracts obtained from two years of cultivation is the varying environmental conditions.

Simple yet effective: Historical proximity variables improve the species distribution models for invasive giant hogweed (Heracleum mantegazzianum s.l.) in Poland.

Species distribution models are scarcely applicable to invasive species because of their breaking of the models' assumptions. So far, few mechanistic, semi-mechanistic or statistical solutions like dispersal constraints or propagule limitation have been applied. We evaluated a novel quasi-semi-mechanistic approach for regional scale models, using historical proximity variables (HPV) representing a state of the population in a given moment in the past. Our aim was to test the effects of addition of HPV sets of different minimal recentness, information capacity and the total number of variables on the quality of the species distribution model for Heracleum mantegazzianum on 116000 km2 in Poland. As environmental predictors, we used fragments of 103 1×1 km, world- wide, free-access rasters from WorldGrids.org. Single and ensemble models were computed using BIOMOD2 package 3.1.47 working in R environment 3.1.0. The addition of HPV improved the quality of single and ensemble models from poor to good and excellent. The quality was the highest for the variants with HPVs based on the distance from the most recent past occurrences. It was mostly affected by the algorithm type, but all HPV traits (minimal recentness, information capacity, model type or the number of the time periods) were significantly important determinants. The addition of HPVs improved the quality of current projections, raising the occurrence probability in regions where the species had occurred before. We conclude that HPV addition enables semi-realistic estimation of the rate of spread and can be applied to the short-term forecasting of invasive or declining species, which also break equal-dispersal probability assumptions.

The use of chemical markers for the identification of farm escapees in feral mink populations.

Variations in the contaminant burden in feral and ranch mink, resulting from differences in their diet, may permit the identification of farm escapees. However, this is only possible in the case of contaminants that accumulate to significantly different levels in the two groups of animals. The main objective of this study was to identify chemical markers whose concentrations differ between feral and ranch mink, by analyzing the accumulation of 13 chemical elements in liver and kidney samples. Total mercury levels were up to 15-fold higher in kidney, and up to 7-fold higher in liver of feral mink compared with ranch mink. The majority of feral mink samples analyzed for mercury, contained concentrations that ranged from 1 to 5 µg/g in kidney (68 %) and from 1 to 5 µg/g in liver (70 %). In comparison, the organs of ranch mink had significantly lower levels of mercury: 95 % of kidney samples had concentrations below 1 µg/g and 82 % of liver samples had concentrations below 1 µg/g. Small geographical variations in Hg levels were observed in mink from the four studied feral populations. Significant differences in Cu concentrations between ranch and feral mink were also detected, with low variation within the two groups. Less pronounced differences were recorded for other chemical elements. These data suggest that Hg and Cu may be used as chemical markers for the identification of first generation mink farm escapees.

Abrasions of the outer silicone insulation of endocardial leads in their intracardiac part: a new mechanism of lead-dependent endocarditis.

AIMS: The aim of the study was to identify and characterize the morphology of abrasions and to establish the frequency of the phenomena and their association with infective endocarditis (IE). METHODS AND RESULTS: A total of 212 endocardial leads removed from 141 consecutive patients-due to IE (32), pocket infection (37), and non-infective indications (72)-were analysed with a stereomicroscope and a scanning electron microscope. The presence of abrasions in the intracardiac part (IP) of the atrial (P < 0.01) and ventricular (P < 0.00002) leads, regardless of its advancement, was strongly associated with IE. There were associations between abrasions in the IP of the ventricular (P < 0.00002) and atrial (P < 0.005) leads and two or more implanted endocardial leads. In atrial leads, there was an association between the presence of any abrasion and passive fixation (P < 0.05), dwell time (P < 0.05), and number of procedures until removal (P < 0.006). The abrasions were classified into three levels of degradation under two subtypes according to the morphology observed with a stereomicroscope. The third level of degradation was the most frequently observed in the IP of the leads. CONCLUSIONS: The abrasion of the outer insulation in the IP of silicone leads was significant regardless of the level of degradation and is associated with IE. The abrasions observed in the IP of the leads were similar to those observed in the intravenous and pocket parts, with predomination of the third level of degradation. There was an association between the presence of any abrasion in the IP of the leads and the number of leads, and in the case of atrial leads between abrasions and fixation type, dwell time, and number of procedures until explantation.

Control of sister chromatid recombination by histone H2AX.

Histone H2AX has a role in suppressing genomic instability and cancer. However, the mechanisms by which it performs these functions are poorly understood. After DNA breakage, H2AX is phosphorylated on serine 139 in chromatin near the break. We show here that H2AX serine 139 enforces efficient homologous recombinational repair of a chromosomal double-strand break (DSB) by using the sister chromatid as a template. BRCA1, Rad51, and CHK2 contribute to recombinational repair, in part independently of H2AX. H2AX(-/-) cells show increased use of single-strand annealing, an error-prone deletional mechanism of DSB repair. Therefore, the chromatin response around a chromosomal DSB, in which H2AX serine 139 phosphorylation plays a central role, "shapes" the repair process in favor of potentially error-free interchromatid homologous recombination at the expense of error-prone repair. H2AX phosphorylation may help set up a favorable disposition between sister chromatids.