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Bellow are some of our most recent scientific releases, enjoy the read.

Bisphenol A Effects in Aqueous Environment on Lemna minor

The link between different plastic waste pollutants and their impact on the natural aquatic environment and food chain remains a constant and growing issue. Bisphenol A (BPA), a known endocrine disruptor produced in large quantities primarily in the industry of polycarbonate plastics, can accumulate in vegetal and animal tissue, thus magnifying through trophic levels.

Maturation of Hydroxyapatite from Biogenic Calcium Source - A Comparative Study 

This research aims to synthesize hydroxyapatite powders from a biogenic calcium source (hen eggshell) and study the effect of two maturation methods (a classical method and a combined short time maturation at 135°C in microwave assisted hydrothermal conditions) on its final properties. The synthesized specimens consist of nanometric polycrystalline particles of carbonated apatite, with enhanced osteogenic effect due to the presence of trace elements, and high crystallinity (up to 72.44%). It was concluded that the maturation conditions impacted the morpho structural and compositional characteristics of the obtained powders, as well as their cytotoxic behavior in contact with mouse osteoblasts MC3T3-E1 culture.

Microbial contamination and survival rate on different types of banknotes

In the COVID-19 pandemic context, numerous concerns have been raised regarding the hygienic status of certain objects we interact with on a daily basis, and especially cash money and their potential to harbor and transmit pathogenic bacteria. Therefore, in the present study, we analyzed different currency bills represented by British pounds (5£, 10£ and 20£), Romanian lei (1 leu, 5 lei and 10 lei), U.S. dollars (1$, 5$ and 10$) and Euros (5€, 10€ and 20€) in order to evaluate the bacterial survival rate and bacterial adherence. We used five reference microorganisms by American Type Culture Collection (ATCC, Manassas, VA, USA): Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 8739, Enterococcus sp. ATCC 19952, Salmonella enterica subsp. enterica serovar Typhi ATCC 6539, Listeria monocytogenes ATCC 7644..

Expansion of the Invasive Plant Species Reynoutria japonica Houtt in the Upper Bistrița Mountain River Basin with a
Calculus on the Productive Potential of a Mountain Meadow

Many invasive plant species use interactions with their anthropic environment as a propagation factor and benefit from climate changes, which have become accentuated in the last decade. The way such species interact with climate changes, as well as their high specific ecological plasticity, gives them a consistent advantage over native plant species. This work aims to demonstrate through a simple calculation the quantification of the productive potential of a wet meadow on which populations of an invasive plant species grew. The loss of productive potential induced by Reynoutria japonica Houtt on a mountain meadow in Ciocănești village, Romania, was the main objective, and a method for the general calculation of such losses can be in the case of the productive potential of the meadows was shown. The degree of anthropization of the studied area was also evaluated, correlating the degree of anthropization with the invasive species’ potential for spreading and affecting the mountain area

Epithelial Sodium Channel Inhibition by Amiloride Addressed with THz Spectroscopy and Molecular Modeling

THz spectroscopy is important for the study of ion channels because it directly addresses the low frequency collective motions relevant for their function. Here we used THz spectroscopy to investigate the inhibition of the epithelial sodium channel (ENaC) by its specific blocker, amiloride. Experiments were performed on A6 cells’ suspensions, which are cells overexpressing ENaC derived from Xenopus laevis kidney. THz spectra were investigated with or without amiloride. When ENaC was inhibited by amiloride, a substantial increase in THz absorption was noticed. Molecular modeling methods were used to explain the observed spectroscopic differences. THz spectra were simulated using the structural models of ENaC and ENaC—amiloride complexes built here. The agreement between the experiment and the simulations allowed us to validate the structural models and to describe the amiloride dynamics inside the channel pore. The amiloride binding site validated using THz spectroscopy agrees with previous mutagenesis studies. Altogether, our results show that THz spectroscopy can be successfully used to discriminate between native and inhibited ENaC channels and to characterize the dynamics of channels in the presence of their specific antagonist.

Mid-term Exposure to Polyvinyl Chloride Microplastic via Ingestion Induces Oxidative Stress in Oreochromis niloticus Liver

Microplastics are considered emergent pollutants as an alarmingly number of reports are indicating the environmental contamination with such agents. Water fauna, especially ichtyofauna, is subjected to an increasing microplastic pollution which leads to detrimental effects on the food chain and general health of the ecosystem. In this study, we exposed juvenile specimens of Oreochromis niloticus to high concentrations of polyvinyl chloride (PVC), the worlds third most widely produced plastic polymer. The specimens and water parameters were closely monitored for 40 days before being sacrificed, tissue samples were collected for histological and biochemical analysis. Low catalase activity was observed in the 1000 ppm exposed group as well as high MDA levels, indicating oxidative stress. Glutathione peroxidase was also significantly less in the 500 and 1000 ppm groups in contrast to the control group. These findings suggest that although considered biologically inert, PVC significantly affects the enzymatic activity in fish organisms.