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[Display omitted] • Ionic liquids without allyl groups can be solidified by electron beam patterning. • Electron beam sensitivity of ionic liquids can be tuned by allyl groups number. • Electron range of ionic liquid is determined based on patterning experiments. • Ionic liquids-based microstructures can be potentially used as photonic components. • Ionic liquids are promising materials for direct writing in high vacuum conditions. The high-energy electrons can induce significant physicochemical changes in ionic liquids (ILs), of which polymerization and solidification are particularly interesting due to potential application in microstructures fabrication using electron beam (EB) patterning. However, the role of allyl and alkyl substituents of cation in these phenomena is not clear. Thus, we investigate the effect of electron dose on microscale polymerization of ammonium- and imidazolium-based ILs with different numbers of polymerizable groups. We show that the minimum electron dose for solidification decreases as the number of allyl substituents in cation is increased. Interestingly, ILs without polymerizable substituents are also solidified by EB irradiation. Consequently, we suggest that IL monomers undergo two mechanisms during EB exposure: free radical chain-growth polymerization via allyl groups and cross-linking between monomer/oligomer/polymer radicals. We also study the applicability of IL thin films for EB lithography in terms of sensitivity and contrast of resist material. Moreover, we demonstrate that suspended polymer structures, potentially attractive as photonic components, can be fabricated out of ILs using controlled-acceleration-voltage electron beam lithography (CAV-EBL). This method enables us to examine the effect of electron energy on the solidification depth in IL layer and, as a consequence, estimate the electron range for this material. [ABSTRACT FROM AUTHOR]

In the recent years, coumarin bioactive compounds have been identified to posess anticancer properties. Therefore, the aim of the present study was to investigate for the first time the efficacy of osthole, umbelliferone, esculin, and 4-hydroxycoumarin, alone and in combination with Temozolomide, in the elimination of deadly brain tumors, anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM) cells via programmed death. Our results indicated that osthole, umbelliferone, esculin, and 4-hydroxycoumarin initiated mainly apoptosis in the T98G and MOGGCCM cells. Osthole was the most effective. It also initiated autophagy in a small percentage of the cell population. The co-incubation with Temozolomide did not increase the pro-apoptotic potential of natural compounds but decreased the level of autophagy in the T98G cells. Apoptosis was associated with reduced mitochondrial membrane potential, activation of caspase 3, inhibition of Bcl-2 expression and the presence of a Bcl-2/Beclin 1. Blocking of Bcl-2 expression resulted in promotion of apoptosis, but not autophagy, in the MOGGCCM and T98G lines. It also sensitized astrocytoma cells, but not GBM, to the combined osthole and TMZ treatment, which was correlated with a reduced level of Beclin 1 and increased expression of caspase 3. Osthole and TMZ, alone and in combination, inhibited the migratory phenotype of the GBM and AA cells. In summary, our results indicated that osthole effectively eliminated glioma cells via apoptosis, what was correlated with Bcl-2/Beclin 1 complex formation. Considering the anti-migratory effect, osthole and Temozolomide display antiglioma potential but it needs further extensive studies. [ABSTRACT FROM AUTHOR]

Furanocoumarins are a class of natural compounds produced by several plants, including those consumed by humans. They have been used medicinally in eastern countries for ages. Given the growing body of evidence about their anticancer potential and observations that naturally occurring compounds potentiate the antitumor activity of chemotherapeutics, more attention is paid to elucidation of the nature of furanocoumarins and the possibility of using thereof in practice. The general mechanism by which furanocoumarins eliminate cancer cells is based on cell cycle blockage and initiation of programmed death like apoptosis or autophagy. The precise molecular mechanism of such an action depends on the chemical structure of furanocoumarins, which is based on the furan ring attached to the coumarin backbone in a linear or angular form as well as the type, location, and number of the substituents attached. The review summarizes the current evidence of the antitumor properties of linear and angular furanocoumarins with special emphasis on the molecular mechanism of elimination of cancer cells via apoptosis and autophagy. Negative aspects of the use of coumarins in anticancer therapy will be also discussed especially in the context of their phototoxicity and potential cancerogenic effect. Unlabelled Image [ABSTRACT FROM AUTHOR]

• Arabinogalactan proteins have characteristic features at different stages of ripening. • There is a correlation between the AGPs content and the ripening stage. • Antibodies against AGPs are a useful tool for analyzing the fruit ripening process. • AGPs are pronounced markers of the progress of the ripening process. Arabinogalactan proteins (AGPs) are constituents of the plant cell walls, which are increasingly being considered as essential molecules in the formation of the extracellular matrix. Given their molecular structure and the advantage of the carbohydrate moiety, the glycosylation level and its modification is assumed as a cause of the functional diversity of AGPs. The aim of current work was to evaluate the molecular features of AGP as a potential molecule involved in the ripening process. For this purpose, tomato fruits were analyzed at specific five stages of ripening using microscopic and molecular tools. The experiment showed that the high content and the occurrence of the AGP molecule with molecular weight around 120 kDa are related to cell wall conditions and the intensity of ongoing glycosylation. At the breaker and/or turning stage, the processes of modification of the sugar moiety and depolymerization begin to prevail. At the red ripe/pink stage, the synthesis process is replaced by the degradation process, which is associated with the disappearance of AGPs with high molecular weights and the appearance of only single sugar residues with very low molecular weights. The occurrence of AGPs with low molecular weight (∼30 kDa) may be used as a marker of the finalization of the ripening process in tomato fruits. All anatomical and morphological alterations in the cell wall confirm the presence of dependencies and connections between components of the cell wall network. We may presume that selected antibodies (JIM13, LM2, LM14) indicate very specific features of the fruit tissue at different stages of ripening; thus, AGP is a molecular and cytological marker of particular stages of the fruit ripening process. [ABSTRACT FROM AUTHOR]

The asymmetric cyclopropanation of a vinylphosphonate using optically active sulfonium and selenonium ylides derived from (−)-menthol and (+)-limonene was developed. The ylides were generated in situ by the reaction of the corresponding sulfonium or selenonium salt in the presence of potassium carbonate or DBU as a base. The transfer of the CHPh and CHCO 2 Et groups into the cyclopropane ring showed moderate diastereoselectivity and excellent enantioselectivity (up to 99:1) for the trans - and cis -products. The absolute configuration of phenyl cyclopropyl was assigned based on comparison to their tolyl analogues. [ABSTRACT FROM AUTHOR]

Earthworm coelomic fluid (CF) is known as a rich source of various bioactive compounds with promising anticancer features. However, it has been demonstrated that CF affects functionality of both, cancer and normal cells. This non-selective activity causes a major problem for medical application of CF. In this study, we present the anticancer activity of the active protein-carbohydrate fraction (AF) isolated from thermally treated CF of earthworm Dendrobaena veneta. The in vitro effect of the AF was examined in human colon model including normal human colon epithelium (CCD 841 CoTr) and human colon adenocarcinoma (HT-29 and LS180) cell lines. We investigated the impact of AF on cell viability neutral red and lactate dehydrogenase assays, morphology May-Grünwald-Giemsa staining assay proliferation MTT tetrazolium salt and BrdU incorporation assays as well as cell cycle progression propidium iodide/RNase staining and the activity of human 20S proteasome the hydrolysis of AMC from a Suc-LLVY-AMC peptide substrate. Additionally, the influence of AF on apoptosis was examined in HT-29 cells by Annexin V/PI, Hoechst 33342 staining and active caspase-3 assays. Our investigation demonstrated that AF at the tested concentration range does not affect the viability and morphology of CCD 841 CoTr cells. Simultaneously, AF inhibits human 20S proteasome activity as well as significantly decreases mitochondrial metabolism, disturbs cell cycle and induces apoptosis via activation of procaspase-3 in HT-29 cancer cells. Obtained results demonstrate the antiproliferative and proapoptotic activity of AF that can be useful in developing therapeutic strategies to treat human colon cancer. [ABSTRACT FROM AUTHOR]