New Hybrid Compounds Combining Fragments of Usnic Acid and Thioether Are Inhibitors of Human Enzymes TDP1, TDP2 and PARP1

Tyrosyl-DNA phosphodiesterase 1 (TDP1) catalyzes the cleavage of the phosphodiester bond between the tyrosine residue of topoisomerase 1 (TOP1) and the 3′ phosphate of DNA in the single-strand break generated by TOP1. TDP1 promotes the cleavage of the stable DNA–TOP1 complexes with the TOP1 inhibitor topotecan, which is a clinically used anticancer drug. This article reports the synthesis and study of usnic acid thioether and sulfoxide derivatives that efficiently suppress TDP1 activity, with IC₅₀ values in the 1.4–25.2 μM range. The structure of the heterocyclic substituent introduced into the dibenzofuran core affects the TDP1 inhibitory efficiency of the compounds. A five-membered heterocyclic fragment was shown to be most pharmacophoric among the others. Sulfoxide derivatives were less cytotoxic than their thioester analogs. We observed an uncompetitive type of inhibition for the four most effective inhibitors of TDP1. The anticancer effect of TOP1 inhibitors can be enhanced by the simultaneous inhibition of PARP1, TDP1, and TDP2. Some of the compounds inhibited not only TDP1 but also TDP2 and/or PARP1, but at significantly higher concentration ranges than TDP1. Leader compound 10a showed promising synergy on HeLa cells in conjunction with the TOP1 inhibitor topotecan.     

New Evidence of the Importance of Weak Interactions in the Formation of PML-Bodies

In this work, we performed a comparative study of the formation of PML bodies by full-length PML isoforms and their C-terminal domains in the presence and absence of endogenous PML. Based on the analysis of the distribution of intrinsic disorder predisposition in the amino acid sequences of PML isoforms, regions starting from the amino acid residue 395 (i.e., sequences encoded by exons 4–6) were assigned as the C-terminal domains of these proteins. We demonstrate that each of the full-sized nuclear isoforms of PML is capable of forming nuclear liquid-droplet compartments in the absence of other PML isoforms. These droplets possess dynamic characteristics of the exchange with the nucleoplasm close to those observed in the wild-type cells. Only the C-terminal domains of the PML-II and PML-V isoforms are able to be included in the composition of the endogenous PML bodies, while being partially distributed in the nucleoplasm. The bodies formed by the C-terminal domain of the PML-II isoform are dynamic liquid droplet compartments, regardless of the presence or absence of endogenous PML. The C-terminal domain of PML-V forms dynamic liquid droplet compartments in the knockout cells (PML^−/−), but when the C-terminus of the PML-V isoform is inserted into the existing endogenous PML bodies, the molecules of this protein cease to exchange with the nucleoplasm. It was demonstrated that the K490R substitution, which disrupts the PML sumoylation, promotes diffuse distribution of the C-terminal domains of PML-II and PML-V isoforms in endogenous PML knockout HeLa cells, but not in the wild-type cells. These data indicate the ability of the C-terminal domains of the PML-II and PML-V isoforms to form dynamic liquid droplet-like compartments, regardless of the ordered N-terminal RBCC motifs of the PML. This indicates a significant role of the non-specific interactions between the mostly disordered C-terminal domains of PML isoforms for the initiation of liquid–liquid phase separation (LLPS) leading to the formation of PML bodies.     

蓝线前景黯淡:为什么公交运量显著增加而公交社区的蓝图没有实现

本文对于连接洛杉矶中心区与长滩中心区之间一条长约35公里的轨道交通路线(即蓝线,Blue Line)进行了分析研究.这条线路经过洛杉矶县一些最贫穷并且被人遗忘的社区.尽管当初线路建设的倡导者和地方政府进行了大量宣传并做出许诺,但这条线路并未能改善周边社区的经济环境.本文以蓝线作为范例,旨在了解内城区地铁站点周围现实存在的和已认识到的阻碍发展的因素.根据对政客、规划者、社区领导者和交通运输专家的一系列访谈所收集的信息,以及广泛细致的现场调查得来的分析数据,作者总结出影响内城地铁站点周边地区发展所缺少的先决条件.     

Evaluation of polyethylene terephthalate as a packaging material for premium quality whole pasteurized milk in Greece

Chemical, microbiological, and sensorial changes in premium quality whole pasteurized milk stored at 4 °C under fluorescent light for one day followed by storage in the dark for an additional 12 days was studied. Milk containers tested included 1 l bottles made of (a) clear PET + UV blocker, 350–400μm in thickness bearing a transparent label, (b) clear PET + UV blocker, 350–400 μm in thickness bearing a white colored label, (c) clear PET 350–400 μm in thickness. Milk packaged in 1 l coated paperboard cartons and stored under the same experimental conditions served as the “commercial control” sample. Data were obtained for lipid oxidation, lipolysis, proteolysis, vitamin A, E, and riboflavin content, microbial growth including mesophilic and psychrotrophic counts and sensorial attributes (odor and taste) of whole pasteurized milk. Results showed satisfactory protection of milk packaged in all containers with regard to microbiological and chemical parameters assessed over the 13 day period. Based on sensory analysis, the shelf life of premium quality whole pasteurized milk tested in the present study was 10–11 days for samples packaged in clear PET+UV bottles and 9–10 days for clear PET bottles and paperboard cartons. Vitamin A losses recorded after 10 days of storage were respectively 15.9, 20.6, and 14.3% for samples packaged in clear PET+UV protected bottles, clear PET, and control samples. Respective losses for Vitamin E were 26.4, 36.6, and 35.0% and for riboflavin 32.9, 38.3, and 32.5%. Clear PET + UV provided equal or better protection to milk as compared to the paperboard carton. Clear PET was the least effective in retaining light-sensitive vitamins. Based on spectral transmission curves of packaging materials tested, it is suggested that the use of a UV blocking agent in combination with a dark color pigmentation (blue, green etc.) in fresh milk packaging will provide a better protection to light-sensitive vitamins in cases where the expected shelf life of milk exceeds 5–6 days.     

Biofiltration of wastewater treatment plant effluent: effective removal of pharmaceuticals and personal care products and reduction of toxicity

This study investigates biofiltration for the removal of dissolved organic carbon (DOC), pharmaceuticals and personal care products (PPCPs), and for the reduction of non-specific toxicity expressed as baseline toxicity equivalent concentration (baseline-TEQ). Two filtering media, sand and granular activated carbon, were tested. The influence of pre-ozonation and empty-bed contact time (EBCT, from 30 to 120 min) was determined. The experiments were performed at a pilot-scale with real WWTP effluent. A previous study showed that biological activity had developed on the filtering media and dissolved organic removal had reached a steady state before sampling commenced. The results show that biological activated carbon (BAC) has a good potential for the removal of DOC (35-60%), PPCPs (>90%) and baseline-TEQ (28-68%) even without pre-ozonation. On the contrary, the sand shows limited improvement of effluent quality. Varying the EBCT does not influence the performance of the BAC filters; however, dissolved oxygen concentration could be a limiting factor. The performances of the BAC filters were stable for over two years suggesting that the main mechanism of organic matter and PPCPs removal is biodegradation. It is concluded that BAC filtration without pre-ozonation could be implemented as a low cost advanced treatment option to improve WWTP effluent chemical quality.     

A new route to steroid ring C aromatization from readily available precursors

3β-Acetoxy-8α,9α-epoxy-5α-cholest-14-ene (1); 3β-acetoxy-14α,15α-epoxy-5α-cholest-8-ene (2); 3β-acetoxy-5α-cholest-8(14)-ene-9α,15α-diol (3); and 3β-acetoxy-5α-cholesta-8(14),9(11)-dien-15α-ol (4) have been aromatized to a 9∶1 mixture of 3β-hydroxy-12-methyl-18-nor-5α,17β(H)-cholesta-8,11,13-triene (5a) and 3β-hydroxy-12-methyl-18-nor-5α,17α(H)-cholesta-8,11,13-triene (5b) in ethanol solution by using hydrochloric acid. The aromatization by action ofp-toluenesulfonic acid gave mainly the epimer with the natural C-17 configuration as the acetate 5c at the appropriatep-toluenesulfonic acid concentration. 3β-Acetoxy-5α-cholesta-7,9(11),14-triene (7a) and 3β-hydroxy-5α-cholesta-8,11,14-triene (8a), 2 intermediary compounds in the aromatization, were isolated and characterized.     

DBPs formation and toxicity monitoring in different origin water treated by ozone and alum/PAC coagulation

In this study, aluminium sulphate (alum) and polyaluminum chloride (PAC) coagulation were used for coagulation of different origin water (Buyukcekmece, BC and Omerli, OM in Istanbul, Turkey and Carmine, CR in Salerno, Italy) treatment. The effect of pre-ozonation alone and combined with coagulation on NOM removal which was characterized by TOC, UV254 was investigated. DBPs formation and acute toxicity on Daphnia magna of chlorinated raw and treated samples were defined in parallel. Moreover, bromide spiking was evaluated for DBPs speciation. Optimum alum dose for TOC removal was found to be 40 mg/L for OM while 80 mg/L of alum exhibited the lowest total trihalomethane formation potential (TTHMFP). Pre-ozonation enhanced the removal of TOC and reduction of TTHMFP when it was used in combination with both coagulants. In contrast, total haloacetic acid formation potential (THAAFP) increased after each coagulation, ozonation and their combination. 300 µg/L bromide spiking (around the same level with BC) in raw sample collected from CR increased the formation of brominated disinfection byproducts. Raw and treated samples displayed acute toxicity on Daphnia magna in different pattern and practically “no dose-response behavior” was observed.     

The In Vitro Cytotoxicity of Eremothecium oil and Its Components—Aromatic and Acyclic Monoterpene Alcohols

The microscopic fungi Eremothecium ashbyi and E. gossypii are known for their ability to synthetize essential oil, which has a composition similar to that of rose oil. The development of Eremothecium oil technology enables the production of rose-scented products, which are demanded by pharmaceutical, food, and perfumery industries. This study focuses on assessing the in vitro cytotoxicity of Eremothecium oil, in comparison with that of rose oil, using a combination of methods and two cell types (3T3 mouse fibroblast cell line and bone-marrow-derived mesenchymal stromal cells (BM-MSCs)). The Eremothecium oil samples possessed cytotoxic effects that varied among strains and batches. The revealed cytotoxicity level may be used to tailor the qualitative and quantitative composition of Eremothecium oil to achieve a particular quality in its end products. These results require further analysis using other cell types and assays based on measuring other cell functions.     

Mitochondrial rRNA Methylation by Mettl15 Contributes to the Exercise and Learning Capability in Mice

Mitochondrial translation is a unique relic of the symbiotic origin of the organelle. Alterations of its components cause a number of severe human diseases. Hereby we report a study of mice devoid of Mettl15 mitochondrial 12S rRNA methyltransferase, responsible for the formation of m⁴C839 residue (human numbering). Homozygous Mettl15^−/− mice appeared to be viable in contrast to other mitochondrial rRNA methyltransferase knockouts reported earlier. The phenotype of Mettl15^−/− mice is much milder than that of other mutants of mitochondrial translation apparatus. In agreement with the results obtained earlier for cell cultures with an inactivated Mettl15 gene, we observed accumulation of the RbfA factor, normally associated with the precursor of the 28S subunit, in the 55S mitochondrial ribosome fraction of knockout mice. A lack of Mettl15 leads to a lower blood glucose level after physical exercise relative to that of the wild-type mice. Mettl15^−/− mice demonstrated suboptimal muscle performance and lower levels of Cox3 protein synthesized by mitoribosomes in the oxidative soleus muscles. Additionally, we detected decreased learning capabilities in the Mettl15^−/− knockout mice in the tests with both positive and negative reinforcement. Such properties make Mettl15^−/− knockout mice a suitable model for mild mitochondriopathies.