Phase Transitions in Confinements: Controlling Solid to Fluid Transitions of Xenon Atoms in an On‐Surface Network

This study reports on “phase” transitions of Xe condensates in on‐surface confinements induced by temperature changes and local probe excitation. The pores of a metal‐organic network occupied with 1 up to 9 Xe atoms are investigated in their propensity to undergo “condensed solid” to “confined fluid” transitions. Different transition temperatures are identified, which depend on the number of Xe atoms in the condensate and relate to the stability of the Xe clustering in the condensed “phase.” This work reveals the feature‐rich behavior of transitions of confined planar condensates, which provide a showcase toward future “phase‐transition” storage media patterned by self‐assembly. This work is also of fundamental interest as it paves the way to real space investigations of reversible solid to fluid transitions of magic cluster condensates in an array of extremely well‐defined quantum confinements.     

Establishment of In Vitro and In Vivo Anticolorectal Cancer Efficacy of Lithocholic Acid-Based Imidazolium Salts

Imidazolium salts (IMSs) are the subject of many studies showing their anticancer activities. In this research, a series of novel imidazolium salts substituted with lithocholic acid (LCA) and alkyl chains of various lengths (S1–S10) were evaluated against colon cancer cells. A significant reduction in the viability and metabolic activity was obtained in vitro for DLD-1 and HT-29 cell lines when treated with tested salts. The results showed that the activities of tested agents are directly related to the alkyl chain length, where S6–S8 compounds were the most cytotoxic against the DLD-1 line and S4–S10 against HT-29. The research performed on the xenograft model of mice demonstrated a lower tendency of tumor growth in the group receiving compound S6, compared with the group receiving 5-fluorouracil (5-FU). Obtained results indicate the activity of S6 in the induction of apoptosis and necrosis in induced colorectal cancer. LCA-based imidazolium salts may be candidates for chemotherapeutic agents against colorectal cancer.     

Efficiency of phospholipid remodeling via acyl-CoA:lysophospholipid acyltransferases action is modified by acyl-CoAs

This study investigated the impact of different acyl-CoAs on remodeling efficiency of PC and PE via the action of acyl-CoA:lysophospholipid acyltransferases (LPLAT). Microsomal fractions from yeast ΔALE1 mutant transformed with an empty plasmid pYES2 or plasmid carrying AtLPCAT or ALE1 encoding genes were used in the experiments. In the preliminary assays, presence of 18:1-CoA in the reaction mixture increased remodeling efficiency of [¹⁴C]PC integrated with microsomal fraction of yeast overexpressing AtLPCAT compared to assays without exogenous acyl-CoA. In further experiments, the effect of five different acyl-CoAs (16:0-CoA, 18:0-CoA, 18:1-CoA, 18:2-CoA, and 18:3-CoA) on remodeling efficiency of yeast microsomal PC and PE via the action of three LPLATs (yeast SLC1 and ALE1 and Arabidopsis LPCAT2) were tested. It has been shown that acyl-CoAs used in the experiments had different effect on the remodeling intensity of PC and PE via action of the tested acyltransferases. Moreover, each acyl-CoA used had a different effect on the tested acyltransferases. Additionally, the assays with DTNB (inhibitor of the LPLAT backward reaction) showed that remodeling of PC and PE by LPLATs can also occur through reactions other than the backward reaction carried out by these enzymes, and that acyl-CoA present in the reaction mixture affected these processes.