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The total oxidizable precursor (TOP) assay has been extensively used for detecting PFAS pollutants that do not have analytical standards. It uses hydroxyl radicals (HO•) from the heat activation of persulfate under alkaline pH to convert H-containing precursors to perfluoroalkyl carboxylates (PFCAs) for target analysis. However, the current TOP assay oxidation method does not apply to emerging PFAS because (i) many structures do not contain C-H bonds for HO• attack and (ii) the transformation products are not necessarily PFCAs. In this study, we explored the use of classic acidic persulfate digestion, which generates sulfate radicals (SO4-•), to extend the capability of the TOP assay. We examined the oxidation of Nafion-related ether sulfonates that contain C-H or -COO-, characterized the oxidation products, and quantified the F atom balance. The SO4-• oxidation greatly expanded the scope of oxidizable precursors. The transformation was initiated by decarboxylation, followed by various spontaneous steps, such as HF elimination and ester hydrolysis. We further compared the oxidation of legacy fluorotelomers using SO4-• versus HO•. The results suggest novel product distribution patterns, depending on the functional group and oxidant dose. The general trends and strategies were also validated by analyzing a mixture of 100000- or 10000-fold diluted aqueous film-forming foam (containing various fluorotelomer surfactants and organics) and a spiked Nafion precursor. Therefore, (1) the combined use of SO4-• and HO• oxidation, (2) the expanded list of standard chemicals, and (3) further elucidation of SO4-• oxidation mechanisms will provide more critical information to probe emerging PFAS pollutants.

Poly-ether-ether-ketone (PEEK) and PEEK composites are outstanding candidates for biomedical applications, such as orthopedic devices, where biocompatibility and modulus match with surrounding tissue are requisite for long-term success. The mechanical properties can be optimized by incorporating fillers such as continuous and chopped carbon fibers. While much is known about the mechanical and tribological behavior of PEEK composites, there are few articles that summarize the viability of using PEEK reinforced with carbon fibers in orthopedic implants. This paper reviews biocompatibility, tribological, and mechanical studies on PEEK and their composites with carbon fibers, notably PEEK reinforced with polyacrylonitrile (PAN)-based carbon fibers and PEEK reinforced with pitch-based carbon fibers, for application in orthopedics and total joint replacements (TJRs). The main objectives of this review are two-fold. Firstly, this paper aims to assist designers in making informed decisions on the suitability of using PEEK and PEEK composites in orthopedic applications; as it is not well understood how these materials perform on the whole in orthopedics and TJRs. Secondly, this paper aims to serve as a centralized paper in which researchers can gain information on the tribological and mechanical advancements of PEEK and PEEK composites.

The Kir1.1 (ROMK) family of weak inward rectifiers controls K secretion in the renal CCT and K recycling in the renal TALH. A single point mutant of the inward rectifier, F127V-Kir1.1b was used to investigate the K transition between the selectivity filter and the outer mouth of the channel. We hypothesize that normally an aromatic Phe at the external entryway of Kir1.1b facilitates outward K secretion. We tested this by replacing F127-Kir1.1b with a small aliphatic Val . Results indicate that removal of the Phe at 127 suppresses outward currents that normally contribute to K secretion. Results with the F127V mutant could be explained by increased polyamine block and/or a decrease in the avidity of Kir1.1 for K ions near the outer mouth of the channel. The latter is supported by F127V-Kir1.1b having a lower affinity (K m  = 33 mM) for K than wild-type Kir1.1b (K m  = 7 mM) during external K elevation. Conversely, chelation of K with 18-Crown-6 ether reduced K conductance faster in F127V (half-time = 6s) than in wt-Kir1.1b (half-time = 120s), implying that F127V is less hospitable to external K. In other experiments, positive membrane potentials gated the F127V mutant channel closed at physiological levels of external Ca, possibly by electrostatically depleting K adjacent to the membrane, suggesting that the Phe residue is critical for outward K secretion at physiological Ca. We speculate that the avidity of wt-Kir1.1b for external K could result from a cation-Pi interaction between K and the aromatic F127.

Per- and polyfluoroalkyl substances (PFASs) are widely used due to their unique structure and excellent performance, while also posing threats on ecosystem, especially long-chain perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). As the control of conventional PFASs, fluoroalkylether substances (ether-PFASs) as alternatives are constantly emerging. Subsequently, the three representative ether-PFASs, chlorinated polyfluoroalkyl ether sulfonic acid (F-53B), hexafluoropropylene oxide-dimer acid (HFPO-DA), and 4,8-Dioxa-3H-perfluorononanoicacid (ADONA) are discovered and have received more attention in the environment and ecosystem. But their security is now also being challenged. This review systematically assesses their security from six dimensions including environmental occurrence in water, soil and atmosphere, as well as bioaccumulation and risk in plants, animals and humans. High substitution level is observed for F-53B, whether in environment or living things. Like PFOS or even more extreme, F-53B exhibits high biomagnification ability, transmission efficiency from maternal to infant, and various biological toxicity effects. HFPO-DA still has a relatively low substitution level for PFOA, but its use has emerged in Europe. Although it is less detected in human bodies and has a higher metabolic rate than PFOA, the strong migration ability of HFPO-DA in plants may pose dietary safety concerns for humans. Research on ADONA is limited, and currently, it is detected in Germany frequently while remaining at trace levels globally. Evidently, F-53B has shown increasing risk both in occurrence and toxicity compared to PFOS, and HFPO-DA is relatively safe based on available data. There are still knowledge gaps on security of alternatives that need to be addressed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The advent of mRNA for nucleic acid (NA) therapeutics has unlocked many diverse areas of research and clinical investigation. However, the shorter intracellular half-life of mRNA compared with other NAs may necessitate more frequent dosing regimens. Because lipid nanoparticles (LNPs) are the principal delivery system used for mRNA, this could lead to tolerability challenges associated with an accumulated lipid burden. This can be addressed by introducing enzymatically cleaved carboxylic esters into the hydrophobic domains of lipid components, notably, the ionizable lipid. However, enzymatic activity can vary significantly with age, disease state, and species, potentially limiting the application in humans. Here we report an alternative approach to ionizable lipid degradability that relies on nonenzymatic hydrolysis, leading to a controlled and highly efficient lipid clearance profile. We identify highly potent examples and demonstrate their exceptional tolerability in multiple preclinical species, including multidosing in nonhuman primates (NHP).

A LigE-type beta-etherase enzyme from lignin-degrading Agrobacterium sp. has been identified, which assists degradation of polymeric lignins. Testing against lignin dimer model compounds revealed that it does not catalyse the previously reported reaction of Sphingobium SYK-6 LigE, but instead shows activity for a β-5 phenylcoumaran lignin dimer. The reaction products did not contain glutathione, indicating a catalytic role for reduced glutathione in this enzyme. Three reaction products were identified: the major product was a cis-stilbene arising from C-C fragmentation involving loss of formaldehyde; two minor products were an alkene arising from elimination of glutathione, and an oxidised ketone, proposed to arise from reaction of an intermediate with molecular oxygen. Testing of the recombinant enzyme against a soda lignin revealed the formation of new signals by two-dimensional NMR analysis, whose chemical shifts are consistent with the formation of a stilbene unit in polymeric lignin., (© 2024 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

Perfluoroalkyl ether carboxylic acids (PFECA) have emerged as novel alternatives to legacy per- and polyfluoroalkyl substances (PFAS). Existing research has revealed hepatoxicity induced by various PFAS, including PFECA. However, these studies have primarily focused on overall changes in whole liver tissue, particularly in hepatocytes, with the impact of PFAS on diverse liver non-parenchymal cells (NPCs) still inadequately understood. In the present study, we examined the heterogeneous responses of hepatic NPCs following exposure to perfluoro-3,5,7,9,11-pentaoxadodecanoic acid (PFO5DoDA), a type of PFECA, by administering PFO5DoDA (5 μg/L)-contaminated water to male mice for one year. Single-cell RNA sequencing (scRNA-seq) of 15 008 cells from the liver identified 10 distinct NPC populations. Notably, although relative liver weight remained largely unchanged following exposure to 5 μg/L PFO5DoDA, there was an observed increase in proliferating cells, indicating that proliferating NPCs may contribute to the hepatomegaly frequently noted in PFAS-exposed livers. There was also a considerable alteration in the composition of hepatic NPCs. Specifically, the total number of B cells decreased substantially, while many other cells, such as monocytes and macrophages, increased after PFO5DoDA exposure. In addition, interactions among the hepatic NPC populations changed variously after PFO5DoDA exposure. The findings emphasize the heterogeneity in the responses of hepatic NPCs to PFO5DoDA exposure. Taken together, the changes in immune cell populations and their intercellular interactions suggest that PFO5DoDA disrupts immune homeostasis in the liver. These findings offer new insights into the cellular mechanisms of PFAS-induced liver damage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Purpose: To evaluate the effects of neodymium-doped yttrium aluminum garnet (Nd: YAG) LASER irradiation and oxygen (O 2 ) plasma on the adhesive performance of polyether ether ketone (PEEK) and resin adhesive., Methods: Nd: YAG LASERs of varying powers and O 2 plasma for different durations were used to modify PEEK. A total of 168 PEEK specimens were randomly divided into seven groups (n = 24/group): (A) Control group: untreated PEEK, (B) L 0.75 group: PEEK modified with 0.75 W Nd: YAG LASER, (C) L 1 group: PEEK modified with 1.0 W Nd: YAG LASER, (D) L 1.25 group: PEEK modified with 1.25 W Nd: YAG LASER, (E) P 15 group: PEEK modified with 15 min of O 2 plasma, (F) P 25 group: PEEK modified with 25 min of O 2 plasma, and (G) P 35 group: PEEK modified with 35 min of O 2 plasma. The surface characteristics of the materials were comprehensively analyzed using a scanning electron microscope (SEM), profilometer, energy-dispersive spectrometer (EDS), and contact angle tester. The adhesive specimens were bonded with Variolink N resin adhesive in all groups and each group was further divided into two subgroups (n = 12/group): (a) water storage for 56 h at 37 °C and (b) thermal cycling 5000 times. Shear bond strength (SBS) was tested using a universal testing machine, and the fracture modes were observed using an automated chemiluminescence analysis system to assess the effects of Nd: YAG LASER and O 2 plasma on the bond strength of PEEK to resin adhesive., Results: Both Nd: YAG LASER and O 2 plasma treatments altered the surface characteristics of PEEK and significantly increased the SBS between PEEK and Variolink N resin adhesive. The L 0.75 group (Nd: YAG LASER) and the P 35 group (O 2 plasma) achieved the highest SBS, respectively. Furthermore, the SBS of the L 0.75 group was higher than that of the P 35 group. Following thermal cycling, SBS values decreased compared to the water storage subgroups. The fracture modes of the specimens in each group were predominantly interfacial and mixed, with no cohesive fractures observed., Conclusions: Nd: YAG LASER irradiation and O 2 plasma treatments can improve the SBS between PEEK and resin adhesive, with the 0.75 W Nd: YAG LASER being the preferred treatment method., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Tetrabromobisphenol A bis (2- hydroxyethyl) ether (TBBPA-DHEE), as one of the main derivatives of Tetrabromobisphenol A, been attracted attention for its health risks. In this study, the neurotoxicity, mechanism, and susceptivity of TBBPA-DHEE exposure to sexually developing male rats were systematically studied. Neurobehavioral research showed that TBBPA-DHEE exposure could significantly affect the behavior, learning,and memory abilities of male-developing rats, and aggravate their depression. TBBPA-DHEE exposure could inhibit the secretion of neurotransmitters. Transcriptomics studies show that TBBPA-DHEE can significantly affect gene expression, and a total of 334 differentially expressed genes are enriched. GO function enrichment analysis shows that TBBPA-DHEE exposure can significantly affect the expression of genes related to synapses and cell components. KEGG function enrichment analysis shows that TBBPA-DHEE exposure can significantly affect the expression of signal pathways related to nerves, nerve development, and signal transduction. Susceptibility analysis showed that female rats were more susceptible to TBBPA-DHEE exposure than male rats. Therefore, TBBPA-DHEE exposure has neurodevelopmental toxicity to male developmental rats, and female developmental rats are more susceptible than male developmental rats. Its possible molecular mechanism is that TBBPA-DHEE may inhibit the secretion of neurotransmitters and affect signal pathways related to neurodevelopment and signal transduction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Neutral and positively charged archaeal ether lipids (AEL) have been studied for their utilization as novel delivery systems for pDNA, showing efficient immune response with a strong memory effect while lacking noticeable toxicity. Recent technological advances placed mRNA lipid nanoparticles (LNPs) at the forefront of next-generation delivery systems; however, no study has examined AELs in mRNA delivery yet. In this study, we investigated either a crude lipid extract or the purified tetraether lipid caldarchaeol from Sulfolobus acidocaldarius as potential novel excipients for mRNA LNPs. Depending on their molar share in the respective LNP, particle uptake, and mRNA expression levels could be increased by up to 10-fold in in vitro transfection experiments using both primary cell sources (HSMM) and established cell lines (Caco-2, C2C12) compared to a well-known reference formulation. This increased efficiency might be linked to a substantial effect on endosomal escape, indicating fusogenic and lyotropic features of AELs. This study shows the high value of archaeal ether lipids for mRNA delivery and provides a solid foundation for future in vivo experiments and further research., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background Context: Methods to improve osseointegration of orthopedic spinal implants remains a clinical challenge. Materials composed of poly-ether-ether-ketone (PEEK) and titanium are commonly used in orthopedic applications due to their inherent properties of biocompatibility. Titanium has a clinical reputation for durability and osseous affinity, and PEEK offers advantages of a modulus that approximates osseous structures and is radiolucent. The hypothesis for the current investigation was that a titanium plasma spray (TPS) coating may increase the rate and magnitude of circumferential and appositional trabecular osseointegration of PEEK and titanium implants versus uncoated controls., Purpose: Using an in vivo ovine model, the current investigation compared titanium plasma-sprayed PEEK and titanium dowels versus nonplasma-sprayed dowels. Using a time course study of 6 and 12 weeks postoperatively, experimental assays to quantify osseointegration included micro-computed tomography (microCT), biomechanical testing, and histomorphometry., Study Design/setting: In-vivo ovine model., Methods: Twelve skeletally mature crossbred sheep were equally randomized into postoperative periods of 6 and 12 weeks. Four types of dowel implants-PEEK, titanium plasma-sprayed PEEK (TPS PEEK), titanium, and titanium plasma-sprayed titanium (TPS titanium) were implanted into cylindrical metaphyseal defects in the distal femurs and proximal humeri (one defect per limb, n=48 sites). Sixteen nonoperative specimens (eight femurs and eight humeri) served as zero time-point controls. Half of the specimens underwent destructive biomechanical pullout testing and the remaining half quantitative microCT to quantify circumferential bone volume within 1 mm and 2 mm of the implant surface and histomorphometry to compute direct trabecular apposition., Results: There were no intra- or perioperative complications. The TPS-coated implants demonstrated significantly higher peak loads at dowel pullout at 6 and 12 weeks compared with uncoated controls (p<.05). No differences were observed across dowel treatments at the zero time-point (p>.05). MicroCT results exhibited no significant differences in circumferential osseointegration between implants within 1 mm or 2 mm of the dowel surface (p>.05). Direct appositional osseointegration of trabecular bone based on histomorphometry was higher for TPS-coated groups, regardless of base material, compared with uncoated treatments at both time intervals (p<.05)., Conclusions: The current in vivo study demonstrated the biological and mechanical advantages of plasma spray coatings. TPS improved histological incorporation and peak force required for implant extraction., Clinical Significance: Plasma spray coatings may offer clinical benefit by improving biological fixation and osseointegration within the first 6 to 12 weeks postoperatively- the critical healing period for implant-based arthrodesis procedures., Competing Interests: Declaration of Competing Interest One or more of the authors declare financial or professional relationships on ICMJE-TSJ disclosure forms., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Structural modification of natural products is an effective approach for improving antifungal activity and has, therefore, been used extensively in the development of new agrochemical products. In this work, a series of novel coumarin derivatives containing oxime ether structures were designed, synthesized, and evaluated for antifungal activity. Some of the designed compounds exhibited promising antifungal activities against tested fungi, and compounds 4a , 4c , 5a , and 6b had EC 50 values equivalent to those of commercial fungicides. Compound 6b was the most promising candidate fungicide against Rhizoctonia solani (EC 50 = 0.46 μg/mL). In vivo antifungal bioassays suggested that compounds 5a and 6b could serve as novel agricultural antifungals. Furthermore, microscopy demonstrated that compound 6b induced the sprawling growth of hyphae, distorted the outline of cell walls, and reduced mitochondrial numbers. Additionally, the effects of the substituent steric, electrostatic, hydrophobic, and hydrogen-bond fields were elucidated using an accurate and reliable three-dimensional quantitative structure-activity relationship (3D-QSAR) model. The results presented here will guide the discovery of potential novel fungicides for plant disease control in agriculture.

Tetrabromobisphenol A-bis(2,3-dibromo-2-methylpropyl ether) (TBBPA-DBMPE) has come into use as an alternative to hexabromocyclododecane (HBCD), but it is unclear whether TBBPA-DBMPE has less hazard than HBCD. Here, we compared the bioaccumulation and male reproductive toxicity between TBBPA-DBMPE and HBCD in mice following long-term oral exposure after birth. We found that the concentrations of TBBPA-DBMPE in livers significantly increased with time, exhibiting a bioaccumulation potency not substantially different from HBCD. Lactational exposure to 1000 μg/kg/d TBBPA-DBMPE as well as 50 μg/kg/d HBCD inhibited testis development in suckling pups, and extended exposure up to adulthood resulted in significant molecular and cellular alterations in testes, with slighter effects of 50 μg/kg/d TBBPA-DBMPE. When exposure was extended to 8 month age, severe reproductive impairments including reduced sperm count, increased abnormal sperm, and subfertility occurred in all treated animals, although 50 μg/kg/d TBBPA-DBMPE exerted lower effects than 50 μg/kg/d HBCD. Altogether, all data led us to conclude that TBBPA-DBMPE exerted weaker male reproductive toxicity than HBCD at the same doses but exhibited bioaccumulation potential roughly equivalent to HBCD. Our study fills the data gap regarding the bioaccumulation and toxicity of TBBPA-DBMPE and raises concerns about its use as an alternative to HBCD.

On December 19, 1846, at the London home of Francis Boott, dentist James Robinson administered the vapor of diethyl ether to a young female patient named Miss Lonsdale. This was the earliest known attempt in England to provide painless operating conditions for a dental extraction, and it was successful. Many authors have since written much about Boott and Robinson, but scarcely anything is known about Miss Lonsdale. In contemporaneous accounts of the event, Robinson referred to his patient as a "young person" and a "young lady"; Boott, however, named her, suggesting that she was publicly recognizable. Our initial attempt to identify Miss Lonsdale was based on genealogical, United Kingdom Census, and other public records, using selection criteria based on age, name recognition, familial relationships, and London addresses. This produced 7 possible candidates from publicly recognizable families, though none was notable in her own right. Our second attempt was based primarily on contemporaneous newspaper records, among which were published 2 private letters in which Boott referred to Robinson's patient as a "girl." We found that "Miss Lonsdale" was the publicly recognizable name of 2 young stage-performing sisters, Adeline Lonsdale, a danseuse, and Annie Lonsdale, an actor-comedienne. Both subsequently emigrated to the United States where they were well-known stage performers. Accordingly, we suggest that both are highly probable candidates for that etherized patient, with the younger sister Adeline then more publicly recognizable. However, no records were found that directly associated any of the Miss Lonsdale candidates with that first dental anesthetic in England., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 International Anesthesia Research Society.)

The development of biobased fire-safe thermosets with recyclability heralds the switch for a transition towards a circular economy. In this framework, we introduced a novel high-performance bio-epoxy vitrimer (named GVD), which was fabricated by forming a crosslinking network between bio-epoxy glycerol triglycidyl ether (Gte), varying amounts of reactive flame-retardant agent 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) (0-7 wt%) and a vanillin-based hardener (VA) with imine bonds. For instance, the epoxy vitrimer GVD5, featuring a DOPO content of 5 wt%, achieved a V-0 rating in the vertical burning test (UL-94) and obtained a limiting oxygen index (LOI) value of 31 %, surpassing the performance of pristine epoxy. Furthermore, the peak heat release rate and total heat release of GVD5 were reduced by 38.2 % and 26.3 %, respectively, compared to pristine epoxy. The GVD vitrimers further demonstrated exceptional reprocessability and recyclability, attributed to the presence of dynamic imine bonds within the topological crosslinking network. Remarkably, the epoxy vitrimers maintained the mechanical properties of the parent epoxy. Therefore, this work provides a facile strategy for fabricating high-performance and multi-functional bio-epoxy thermosets., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. RIFM staff are employees of the Research Institute for Fragrance Materials, Inc. (RIFM). The Expert Panel receives a small honorarium for time spent reviewing the subject work.

Background: In ruminants, fibrous feedstuffs must be included in the ration to ensure normal rumen physiology and to prevent the occurrence of rumen-related metabolic diseases. In addition to being a source of fibrous feedstuffs, they contain energy depending on the level of digestion and protein, minerals, fatty acids, minerals, and secondary compounds., Objectives: This study aimed to determine the nutrient matter, fatty acid, mineral and in vitro rumen fermentation values of the pennyroyal (Mentha pulegium L.) plant., Methods: The pennyroyal plant samples were collected at different phenological stages (vegetative, full flowering, and seed bulking) from the natural meadow. The samples were analysed for core nutrients, condensed tannins, minerals, fatty acids, and in vitro ruminal fermentation parameters., Results: The calcium (Ca) and iron (Fe) contents and in vitro ruminal fermentation parameters (total gas production and methane production, organic matter digestion (OMd), and the ammonia-nitrogen) decreased with increasing phenological stage (p < 0.05). The percentages of linoleic, α-linolenic, ω-3, ω-6 and polyunsaturated fatty (PUFA) acids of the pennyroyal plant linearly increased with the phenological stages (p < 0.05). However, butyric acid (BA) concentration in the in vitro ruminal fermentation fluid in the full flowering stage was lower than that of other stages (p < 0.05)., Conclusions: Pennyroyal plant is a functional plant in terms of high values of ether extract (EE), α-linolenic acid, linoleic acid, ∑ω-3 fatty acids, Ca, Fe and Zn contents. For this plant to be used as animal feed, the stage when it has the highest values for Ca, Mg, S and Zn minerals and in vitro OMd were vegetative and full flowering. The stage with good potential as animal feed for ∑ω-3 and ∑ω-6 fatty acids and core nutrients (CP and EE) is the seed bulking stage., (© 2024 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Understanding anaerobic biodegradation of ether oxygenates beyond MTBE in groundwater is important, given that it is replaced by ETBE as a gasoline additive in several regions. The lack of studies demonstrating anaerobic biodegradation of ETBE, and its product TBA, reflects the relative resistance of ethers and alcohols with a tertiary carbon atom to enzymatic attack under anoxic conditions. Anaerobic ETBE- or TBA-degrading microorganisms have not been characterized. Only one field study suggested anaerobic ETBE biodegradation. Anaerobic (co)metabolism of ETBE or TBA was reported in anoxic microcosms, indicating their biodegradation potential in anoxic groundwater systems. Non-isotopic methods, such as the detection of contaminant loss, metabolites, or ETBE- and TBA-degrading bacteria are not sufficiently sensitive to track anaerobic biodegradation in situ. Compound- and position-specific stable isotope analysis provides a means to study MTBE biodegradation, but isotopic fractionation of ETBE has only been studied with a few aerobic bacteria (εC -0.7 to -1.7‰, εH -11 to -73‰) and at one anoxic field site (δ 2 H-ETBE +14‰). Similarly, stable carbon isotope enrichment (δ 13 C-TBA +6.5‰) indicated TBA biodegradation at an anoxic field site. CSIA and PSIA are promising methods to detect anaerobic ETBE and TBA biodegradation but need to be investigated further to assess their full potential at field scale., (© 2024. The Author(s).)

Adsorptive separation membranes are widely utilized for the removal of toxic dyeing pollutants from dyeing wastewater. However, developing novel adsorption membranes with large adsorption capacities and enhanced adsorption performance for dyes in actual wastewater poses a significant challenge. This study focuses on the fabrication of crown ether-containing copolymer porous membrane (CRPM) and investigation of the adsorption performance of dyes from aqueous solutions. The morphology structure and pore size distribution revealed that the membrane was endowed with rich micropores and hierarchical porous structures. Three typical cationic dyes (MB, RhB, CV) and an anionic dye (MO) were selected to evaluate the adsorption behavior. The results of adsorption isotherms and kinetics demonstrated that the adsorption data could be well-fitted using the Freundlich and pseudo-first-order kinetic models, the thermodynamic parameters revealed that the adsorption process of dyes on CRPM is a spontaneous endothermic reaction. The membrane exhibited excellent adsorption performance for cationic dyes, with RhB displaying a higher maximum adsorption capacity than previously reported porous membranes. Notably, dynamic adsorption-desorption filtration demonstrated a rapid removal efficiency, with RhB, MB, and CV achieving removal rates of 99.09%, 98.63%, and 99.14% respectively, after five cycles. The filtration volume of the CRPM membrane was 2.4-fold greater than that of a traditional PVDF membrane when applied to actual dyeing wastewater. DFT theoretical calculations were employed to elucidate the adsorption mechanism. These calculations confirmed the significant roles of electrostatic interactions, H-bonds and π-π interactions in facilitating the high-efficiency adsorption of cationic dyes. These findings highlight the potential of the crown ether-containing copolymer as a promising material for adsorption separation membranes in the treatment of dyeing wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. RIFM staff are employees of the Research Institute for Fragrance Materials, Inc. (RIFM). The Expert Panel receives a small honorarium for time spent reviewing the subject work.

The authors report on a mild, label-free, and fast method for the separation of human umbilical vein endothelial cells (HUVEC), which are relevant cells, whose use is not limited to studies of endothelial dysfunction, from cocultures with macrophages to afford HUVEC in ≈100% purity. Poly(di(ethylene glycol)methyl ether methacrylate) (PDEGMA) brushes with a dry thickness of (5 ± 1) nm afford the highly effective one-step separation by selective HUVEC detachment, which is based on the brushes' thermoresponsive behavior. Below the thermal transition at 32 °C the brushes swells and desorbs attached proteins, resulting in markedly decreased cell adhesion. Specifically, HUVEC and macrophages, which are differentiated from THP-1 monocytes, are seeded and attached to PDEGMA brushes at 37°C. After decreasing the temperature to 22°C, HUVEC shows a decrease in their cell area, while the macrophages are not markedly affected by the temperature change. After mild flushing with a cell culture medium, the HUVEC can be released from the surface and reseeded again with ≈100% purity on a new surface. With this selective cell separation and removal method, it is possible to separate and thereby purify HUVEC from macrophages without the use of any releasing reagent or expensive labels, such as antibodies., (© 2023 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH.)

S-palmitoylation is a dynamic lipid-based protein post-translational modification facilitated by a family of protein acyltransferases (PATs) commonly known as DHHC-PATs or DHHCs. It is the only lipid modification that is reversible, and this very fact uniquely qualifies it for therapeutic interventions through the development of DHHC inhibitors. Herein, we report that 4″-alkyl ether lipophilic derivatives of EGCG can effectively inhibit protein S-palmitoylation in vitro. With the help of metabolic labeling followed by copper(I)-catalyzed azide-alkyne cycloaddition Click reaction, we demonstrate that 4″-C 14 EGCG and 4″-C 16 EGCG markedly inhibited S-palmitoylation in various mammalian cells including HEK 293T, HeLa, and MCF-7 using both in gel fluorescence as well as confocal microscopy. Further, these EGCG derivatives were able to attenuate the S-palmitoylation to the basal level in DHHC3-overexpressed cells, suggesting that they are plausibly targeting DHHCs. Confocal microscopy data qualitatively reflected spatial and temporal distribution of S-palmitoylated proteins in different sub-cellular compartments and the inhibitory effects of 4″-C 14 EGCG and 4″-C 16 EGCG were clearly observed in the native cellular environment. Our findings were further substantiated by in silico analysis which revealed promising binding affinity and interactions of 4″-C 14 EGCG and 4″-C 16 EGCG with key amino acid residues present in the hydrophobic cleft of the DHHC20 enzyme. We also demonstrated the successful inhibition of S-palmitoylation of GAPDH by 4″-C 16 EGCG. Taken together, our in vitro and in silico data strongly suggest that 4″-C 14 EGCG and 4″-C 16 EGCG can act as potent inhibitors for S-palmitoylation and can be employed as a complementary tool to investigate S-palmitoylation., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Purpose: The aim of this study was to evaluate the surface wear and retention force of telescopic attachments made of zirconia primary crowns and poly-ether- ketone -ketone (PEKK) secondary crowns for 2-implant retained mandibular complete overdentures., Materials and Methods: Ten healthy completely edentulous patients aged 55-60 years were selected for this study. Each patient received two implants in the mandibular canine regions. Maxillary conventional complete dentures were constructed against implant-retained mandibular overdentures for all patients. Zirconia- PEKK telescopic attachments were fabricated to retain the overdentures where primary copings were constructed of zirconia and secondary ones were constructed of PEKK. Retention force and surface wear were evaluated at the time of overdenture insertion (T0), and after 6 months of overdenture use (T6)., Results: The results revealed less wear of zirconia copings compared to PEKK ones at T0 and T6. However, both materials showed insignificant wear after 6 months of overdenture use. A significant increase in retention force was observed after 6 months of overdenture use., Conclusion: Within limitations of this study, PEKK may be considered a promising alternative material for telescopic secondary crowns construction combined to zirconia primary ones, regarding the wear resistance and the satisfactory retention forces., (Copyright© 2024 Dennis Barber Ltd.)

This study aimed to evaluate the bioactivity of poly(ether ether ketone) (PEEK) after surface modification by persistent photoconductive strontium titanate (SrTiO 3 ) magnetron sputtering and ultraviolet (UV) C irradiation. According to the different modifications, the PEEK specimens were randomly divided into five groups ( n = 38/group): PEEK, Sr100-PEEK, Sr200-PEEK, UV/PEEK, and UV/Sr200-PEEK. Then, the specimens of Sr100-PEEK and Sr200-PEEK groups were, respectively, coated with 100 and 200 nm thickness photocatalyst SrTiO 3 on the PEEK surface by magnetron sputtering. Subsequently, UV-C light photofunctionalized the specimens of PEEK and Sr200-PEEK groups to form UV/PEEK and UV/Sr200-PEEK groups. The specimens were characterized by a step meter, scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDX), and a water contact angle meter. The release test of the Sr ion was performed by inductively coupled plasma mass spectrometry (ICP-MS). In vitro study, osteogenic activity (MC3T3-E1 osteoblast-like cells) and epithelial and connective tissue attachment (gingival epithelial cells GE1 and fibroblasts NIH3T3) were analyzed in five groups. Surface morphology of the specimens was changed after coating, and the Sr content on the Sr-PEEK surface was increased with increasing coating thickness. In addition, the contact angle was increased significantly after magnetron sputtering. After UV-C photofunctionalization, the content of surface elements changed and the contact angle was decreased. The release of Sr ion was sustained, and the final cumulative release amount did not exceed the safety limit. In vitro experiments showed that SrTiO 3 improved the cell activity of MC3T3-E1 and UV-C irradiation further enhanced the osteogenic performance of PEEK. Besides, UV-C irradiation also significantly promoted the cell viability, development, and expression of adhesion proteins of GE1 and NIH3T3 on PEEK. The present investigation demonstrated that nano SrTiO 3 coating with UV-C photofunctionalization synergistically enhanced the osteogenic properties and soft tissue sealing function of PEEK in vitro.

Novel terminally perfluorobutyl group-containing ether-linked phosphatidylcholines with different alkyl chain lengths (di-O-F4-Cn-PCs, n = 14,16 and 18) were developed as possible materials for stable liposomes aiming at applications of structural and functional analyses of membrane proteins. Differential scanning calorimetric investigations of the thermotropic transition of hydrated di-O-F4-Cn-PC bilayers demonstrated that the transition temperature of every di-O-F4-Cn-PC decreases by ~20 °C compared to their corresponding non-fluorinated PCs, di-O-Cn-PCs. With the elongation of the hydrophobic chain, on the other hand, the transition enthalpy (ΔH) and entropy (ΔS) increased in a linear manner. Comparison of ΔH and ΔS values against the net hydrocarbon chain length between di-O-F4-Cn-PCs and di-O-Cn-PCs strongly suggests that in the thermotropic transition of the di-O-F4-Cn-PC membrane, the perfluorobutyl segments undergo very limited structural changes; therefore, the hydrocarbon segments are mainly responsible for the phase transition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The efficient conversion of cellulose to high value-added products is important for the utilization of cellulose biomass. Achieving efficient cellulose hydrolysis and timely products separation is the essential target. Herein, a modified sulfonated graphene oxide/polydopamine deposited polyethersulfone (mGO(SO 3 H)-PDA/PES) membrane reactor, combining in the same unit a conversion effect and a separation effect, was prepared by suction filtration and subsequent polymerization and adhesion. The structure of PES membrane and deposition of PDA was regulated to sure that small molecules can pass through the membrane, while cellulose could not. As a result, the mGO(SO 3 H)-PDA/PES membrane realized the efficient cellulose hydrolysis and timely products separation under cross-flow circulation mode at 0.1 MPa, avoiding the further degradation of reducing sugar products. The yields of total reducing sugar (TRS) and glucose in separated hydrolysate reached 93.2 % and 85.5 %, respectively. This strategy provides potential guidance for efficient conversion of cellulose., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

In bone tissue engineering (BTE), defects in large bones remain the greatest issue which can be addressed using bone scaffolds. In this work, blends of heat cured polymethylmethacrylate (HC PMMA) and various weight percentages of poly-ether-ketone-ketone (PEKK) (0, 2, 4, 8, and 10%) were made using a porogen leaching process. The blends were then subjected to tensile, compression and bending tests to select the optimum blend. Based on the results obtained, HC PMMA blended with 2 wt% PEKK was selected to produce the bio-porous blends. Here, the porosity was imparted using tartaric acid (C 4 H 6 O 6 ) and sodium hydrogen carbonate (NaHCO 3 ) as porogen leaching components. Porous blends resulted were then reinforced with a nano titanium dioxide powder (nTiO 2 ) at different weight percentages of (0, 1, 3, and 5). The results showed that porous composites made of (HC PMMA: 2 wt% PEKK) blend reinforced with 5 wt % nTiO 2 exhibit the highest strength values under various loadings. The FTIR identified the functional groups of the bone scaffold components. The mean pore size and pore depth were measured using atomic force microscopy (AFM) analysis and the values are 92.6 nm and 42.78 nm, respectively. The good distribution of the PEKK and nTiO 2 within the HC PMMA and the uniform porous structure with multi-scale pores between 535 nm and 1.187 mm were confirmed by the AFM data and SEM images, respectively. This research expected that the porous composite (HC PMMA: 2% PEKK: 5% nTiO 2 ) is a good candidate for bone scaffold applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a worldwide scourge with more than 10 million people affected yearly. Among the proteins essential for the survival of Mtb, InhA has been and is still clinically validated as a therapeutic target. A new family of direct diaryl ether inhibitors, not requiring prior activation by the catalase peroxidase enzyme KatG, has been designed with the ambition of fully occupying the InhA substrate-binding site. Thus, eleven compounds, featuring three pharmacophores within the same molecule, were synthesized. One of them, 5-(((4-(2-hydroxyphenoxy)benzyl)(octyl)amino)methyl)-2-phenoxyphenol (compound 21), showed good inhibitory activity against InhA with IC 50 of 0.70 µM. The crystal structure of compound 21 in complex with InhA/NAD + showed how the molecule fills the substrate-binding site as well as the minor portal of InhA. This study represents a further step towards the design of new inhibitors of InhA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The current work focuses on the comprehensive characterization of a 3D printable biomaterial, polyether ketone ketone (PEKK). The PEKK granules are first characterized and then utilized for extrusion of the PEKK filaments. The extruded PEKK filaments are characterized for crystallinity, quality, and printability, wherein they exhibit amorphous nature, good quality, and appropriate printability. Utilizing the filaments, the samples are printed with the appropriate printing parameters, which are further characterized for layer adhesion, voids, and crystallinity, wherein they showed seamless layer adhesion, improper beads consolidation, and the amorphous nature. The as printed samples are further annealed at different temperatures (200 and 250 °C). The scanning electron microscopy (SEM) of the annealed samples (A-200 and A-250) revealed better void consolidation, while the X-ray diffraction (XRD) revealed better crystallinity compared to the un-annealed sample. The printed samples are also investigated for dynamic mechanical analysis (DMA), shape memory, and tensile properties. The storage moduli of the annealed samples are observed to be better than the un-annealed sample. The annealed samples exhibited better shape memory properties: shape fixity and shape recovery ratio of A-200 and A-250 samples, 90.28 and 90.75%, and 99.16 and 94.73%, respectively, compared to the un-annealed samples. The highest shape fixity ratio and the shape recovery ratio are noted for A-250 (90.75%) and A-200 (∼ 100%). The A-200 and A-250 samples showed enhanced tensile modulus and strength, 4.16 and 49.67%, and 36.61 and 35.06%, respectively compared to the un-annealed sample. The highest modulus is noted for A-250, while the strength is comparable (36.61 and 35.06%) for A-200 and A-250., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The brominated flame retardant tetrabromobisphenol A-bis(2,3-dibromo-2-methylpropyl ether) (TBBPA-DBMPE) is a recommended substitute for hexabromocyclododecane (HBCD), a banned persistent organic pollutant, yet its potential toxicities remains largely unexplored. Here, we investigated the effects of a long-term exposure to TBBPA-DBMPE at nominal doses of 50 and 1000 μg/kg/d on lipid homeostasis in CD-1 mice, in comparison with 50 μg/kg/d HBCD as a positive control. Male pups received chemical treatments through maternal administration via drinking water from postnatal day 0-21, followed by direct administration through drinking water after weaning. On the 23rd week after treatment, the oral lipid tolerance test revealed that low-dose TBBPA-DBMPE as well as HBCD affected lipid tolerance, although the fasting serum triglyceride (TG) levels were not altered. When chemical treatment was extended to the 32nd week, TBBPA-DBMPE-treated animals displayed adipocyte hypertrophy in both white adipose tissue (eWAT) and brown adipose tissue (BAT) and hepatic steatosis, which was largely consistent with the effects of HBCD. These findings indicate that like HBCD, TBBPA-DBMPE led to increased lipid load in mice. Interestingly, we also observed intestinal histological changes, coupled with increased expression of lipid absorption-related genes in both HBCD and TBBPA-DBMPE treatments, suggesting increased lipid absorption. This was supported by in vitro findings that both HBCD and TBBPA-DBMPE promoted lipid accumulation in IEC-6 cells under the stress of oleic acid for 6 h, implying that altered lipid absorption by the intestine may partly contributed to increased lipid load in mice. Overall, the effects of 50 μg/kg/d TBBPA-DBMPE in terms of some parameters were comparable with 50 μg/kg/d HBCD, suggesting that TBBPA-DBMPE may not be an ideal substitute of HBCD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The known oxygenated polyhalogenated diphenyl ether, 2-(2',4'-dibromophenoxy)-3,5-dibromophenol ( 1 ), with previously reported activity in multiple cytotoxicity assays was isolated from the sponge Lamellodysidea sp. and proved to be an amenable scaffold for semisynthetic library generation. The phenol group of 1 was targeted to generate 12 ether analogues in low-to-excellent yields, and the new library was fully characterized by NMR, UV, and MS analyses. The chemical structures for 2 , 8 , and 9 were additionally determined via single-crystal X-ray diffraction analysis. All natural and semisynthetic compounds were evaluated for their ability to inhibit the growth of DU145, LNCaP, MCF-7, and MDA-MB-231 cancer cell lines. Compound 3 was shown to have near-equivalent activity compared to scaffold 1 in two in vitro assays, and the activity of the compounds with an additional benzyl ring appeared to be reliant on the presence and position of additional halogens.

Nucleophilic deprotection of p-methoxybenzyl (PMB) [p-methoxyphenylmethyl (MPM)] ethers was developed using a heterogeneous oxovanadium catalyst V-MPS4 and a thiol nucleophile. The deprotection method had a wide reaction scope, including PMB ethers of primary, secondary, and tertiary alcohols bearing various functional groups. In addition, the PMB ether of an oxidation-labile natural product was successfully removed by V-MPS4 catalysis, while a common oxidative method of PMB deprotection afforded a complex mixture. The V-MPS4 catalyst was reusable up to six times without a significant loss in the product yield. The advantages of using the heterogeneous catalyst were further demonstrated by conducting the deprotection reaction in a continuous flow process, which resulted in a 2.7-fold higher catalyst turnover number and 60-fold higher turnover frequency compared to those of the corresponding batch reaction.

Functionalized aryl polyhydroxylated compounds could be of great synthetic value for natural product synthesis. However, the synthesis of such compounds usually requires multi-step synthesis or the usage of sensitive reagents. We present here a practically simple route for the synthesis of such functionalized arylpolyols from glycal derived α,β-unsaturated 2,3-dideoxy aldehyde as well as α,β-saturated 2,3-dideoxy aldehyde (Perlin aldehydes) via Mukaiyama cross aldol condensation in the presence of silyl enol ether and TiCl 4. It was observed that the nature of the electronic substitution of the silyl enol ether does not play any role in the yield of the desired products. Further functionalization of the products has also been shown., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

In order to reduce the impact of greenhouse gases on the environment, the development of various new CO 2 capture materials has become a hot spot. In this work, a novel composite amine solid adsorbent was prepared by simultaneously using tetraethylenepentamine (TEPA) and 2-[2-(dimethylamino) ethoxy] ethanol (DMAEE) for amine functionalization on the polyester microsphere carrier. The introduction of methyl methacrylate (MMA) with high glass transition temperature into the polyester carrier makes the carrier microspheres have high hardness. At the same time, the carrier also contains active epoxy groups and hydrophobic glycidyl methacrylate (GMA, which can undergo ring-opening reaction with composite amines to achieve high-load and low-energy chemical grafting of amines on the carrier. The composite aminated polyester microspheres were used as an efficient adsorbent for CO 2 in simulated flue gas. The results show that the synergistic effect of TEPA-DMAEE composite amine system in the adsorbent is beneficial to the improvement of CO 2 capture capacity. When the total amine content in the impregnating solution is 45 wt% and the composite amine ratio is TEPA: DMAEE = 6: 4, the CO 2 adsorption capacity can reach the optimal value of 2.45 mmol/ g at 70 °C. In addition, the composite amine microsphere adsorbent has cyclic regeneration performance. Importantly, through kinetic fitting, the Avrami kinetic model fits the CO 2 adsorption better than the quasi-first-order and quasi-second-order kinetic models, which proves that physical adsorption and chemical adsorption coexist in the adsorption process. This simple, long-term stable and excellent selective separation performance makes amine-functionalized adsorbents have potential application prospects in CO 2 capture., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study aimed to examine how the addition of etheric compounds (EC) affects the characteristics of myofibrillar proteins (MP) and to understand underlying interaction mechanisms. Fourier transform infrared spectroscopy confirmed that the EC-MP complex was formed through hydrogen bonding. The addition of EC resulted in an increase in the α-helix content and a decrease in the β-sheet content of MP, which would promote the protein unfolding. The unfolding of MP led to aggregation and formation of larger and non-uniform particles. As a result, the exposure of negative charge on the MP surface was enhanced, and zeta potential was decreased from -5.33 mV to -7.45 mV. Moreover, the EC-induced modification of MP conformation resulted in a less rigid three-dimensional network structure of MP gel and enhanced the discharge of aldehyde compounds (C > 6). Moreover, the rheological characteristics of MP were enhanced by the suppression of protein-protein interactions due to the MP unfolding. Molecular dynamics simulations revealed that anethole reduced the binding capacity of myosin to decanal by raising its binding energy from -22.22 kcal/mol to -19.38 kcal/mol. In the meantime, anethole competed for the amino acid residue (PHE165) where myosin connects to decanal. This caused the hydrogen bonds and hydrophobic contacts between the two molecules to dissolve, altering myosin's conformation and releasing decanal. The results might be useful in predicting and controlling the ability of proteins to release and hold onto flavors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Background: A fluorochemical facility near Fayetteville, North Carolina, emitted per- and polyfluoroalkyl ether acids (PFEAs), a subgroup of per- and polyfluoroalkyl substances (PFAS), to air., Objective: Analyze PFAS in private wells near the facility and in blood from well users to assess relationships between PFEA levels in water and serum., Methods: In 2019, we recruited private well users into the GenX Exposure Study and collected well water and blood samples. We targeted 26 PFAS (11 PFEAs) in water and 27 PFAS (9 PFEAs) in serum using liquid chromatography-mass spectrometry. We used regression modeling to explore relationships between water and serum PFAS. For the only PFEA detected frequently in water and serum, Nafion byproduct 2, we used generalized estimating equation (GEE) models to assess well water exposure metrics and then adjusted for covariates that may influence Nafion byproduct 2 serum concentrations., Results: We enrolled 153 participants ages 6 and older (median = 56 years) using 84 private wells. Most wells (74%) had ≥6 detectable PFEAs; median ∑PFEAs was 842 ng/L (interquartile range = 197-1760 ng/L). Low molecular weight PFEAs (PMPA, HFPO-DA [GenX], PEPA, PFO2HxA) were frequently detected in well water, had the highest median concentrations, but were not detectable in serum. Nafion byproduct 2 was detected in 73% of wells (median = 14 ng/L) and 56% of serum samples (median = 0.2 ng/mL). Cumulative dose (well concentration × duration at address) was positively associated with Nafion byproduct 2 serum levels and explained the most variability (10%). In the adjusted model, cumulative dose was associated with higher Nafion byproduct 2 serum levels while time outside the home was associated with lower levels., Impact: PFAS are a large class of synthetic, fluorinated chemicals. Fluorochemical facilities are important sources of environmental PFAS contamination globally. The fluorochemical industry is producing derivatives of perfluoroalkyl acids, including per- and polyfluoroalkyl ether acids (PFEAs). PFEAs have been detected in various environmental samples but information on PFEA-exposed populations is limited. While serum biomonitoring is often used for PFAS exposure assessment, serum biomarkers were not good measures of long-term exposure to low molecular weight PFEAs in a private well community. Environmental measurements and other approaches besides serum monitoring will be needed to better characterize PFEA exposure., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Discoidal lipid nanoparticles (LNPs) called Nanodiscs (NDs) are derived from human high-density lipoprotein (HDL). Such biomimetics are ideally suited for the stabilization and delivery of pharmaceuticals, including chemicals, bio-active proteins and vaccines. The stability and circulation lifetimes of reconstituted HDL nanoparticles, including NDs, are variable. Lipids found in thermophilic archaea and bacteria are prime candidates for the stabilization of LNPs. We report the thermal stability of NDs prepared with lipids that differ in saturation, have either ether- or ester linkages between the fatty acid and glycerol backbone or contain isoprenoid fatty acid tails (phytanyl lipids). NDs with two saturated fatty acids show a much greater long-term thermostability than NDs with an unsaturated fatty acid. Ether fatty acid linkages, commonly found in thermophiles, did not improve stability of NDs compared to ester fatty acid linkages when using saturated lipids. NDs containing phytanyl and saturated alkyl fatty acids show similar stability at 37 °C. NDs assembled with phytanyl lipids contain three copies of the membrane scaffolding protein as opposed to the canonical dimer found in conventional NDs. The findings present a strong basis for the production of thermostable NDs through the selection of appropriate lipids and are likely broadly applicable to LNP development., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Marcellus Ubbink reports financial support was provided by The Dutch Research Council (NWO). Marcellus Ubbink reports a relationship with Batavia Biosciences BV that includes: funding grants. Marcellus Ubbink reports a relationship with ZoBio BV that includes: funding grants. The authors disclose a potential competing interest due to an ongoing patent filing related to the topics discussed in this study. The project was funded by the Dutch Research Council with financial contributions by Batavia Biosciences B.V. and ZoBio B.V., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The asymmetric synthesis of polyunsaturated triene C18:3 n-3 and C18:3 n-6 methoxylated ether lipids (MEL) of the 1- O -alkyl- sn -glycerol type is described as possible structural candidates for a triene C18:3 MEL of an unknown identity found in a mixture of shark and dogfish liver oil. Their C18:3 hydrocarbon chains constitute an all- cis methylene skipped n-3 or n-6 triene framework, along with a methoxyl group at the 2'-position and R -configuration of the resulting stereogenic center. The methoxylated polyenes are attached by an ether linkage to the pro-S hydroxymethyl group of the glycerol backbone. The syntheses were based on the polyacetylene approach that involves a semi-hydrogenation of the resulting triynes. Both syntheses were started from our previously described enantio- and diastereomerically pure isopropylidene-protected glyceryl glycidyl ether, a double-C3 building block that was designed as a head group synthon for the synthesis of various types of MELs.

Preparing a super-tough polylactic acid (PLA) material while maintaining its biodegradability is a significant challenge. This study synthesized a biodegradable unsaturated poly(butylene succinate-co-fumarate)-poly(ethylene glycol) multiblock copolymer (PBSFG) and dynamically vulcanized it with PLA to obtain super-tough blends. The PBSFG self-vulcanized and formed a crosslinked "hard-soft" core-shell rubber phase in the blending process, where the PBSF segment acted as the core and PEG as the shell. As a result, the elongation at break and notched Izod impact strength of PLA increased significantly from 3 % to 66 % and from 3.2 to 58.0 kJ/m 2 , respectively. Furthermore, adding a small amount of dicumyl peroxide (DCP) promoted dynamic vulcanization and improved the compatibility between PLA and PBSFG. With the addition of 0.03 % DCP, the elongation at break and notched Izod impact strength of PLA/PBSFG were further increased to 218 % and 88.9 kJ/m 2 , respectively. Meanwhile, the crystallization rate of PLA was enhanced by the addition of PBSFG and DCP. The PLA/PBSFG blends also degraded in a proteinase K Tris-HCl buffered buffer solution. Finally, fully biodegradable and super-tough PLA blends were achieved., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Rong YANG reports financial support was provided by National Natural Science Foundation of China. Rong Yang, Chaoyi Cai, and JinChun Li has patent issued to 202310913417.6., (Copyright © 2023 Elsevier B.V. All rights reserved.)