Comparative toxicology of algal cell extracts and pure cyanotoxins: insights into toxic effects and mechanisms of harmful cyanobacteria Raphidiopsis raciborskii.

Ongoing research on cyanotoxins, driven by the socioeconomic impact of harmful algal blooms, emphasizes the critical necessity of elucidating the toxicological profiles of algal cell extracts and pure toxins. This study comprehensively compares Raphidiopsis raciborskii dissolved extract (RDE) and cylindrospermopsin (CYN) based on Daphnia magna assays. Both RDE and CYN target vital organs and disrupt reproduction, development, and digestion, thereby causing acute and chronic toxicity. Disturbances in locomotion, reduced behavioral activity, and weakened swimming capability in D. magna have also been reported for both RDE and CYN, indicating the insufficiency of conventional toxicity evaluation parameters for distinguishing between the toxic effects of algal extracts and pure cyanotoxins. Additionally, chemical profiling revealed the presence of highly active tryptophan-, humic acid-, and fulvic acid-like fluorescence compounds in the RDE, along with the active constituents of CYN, within a 15-day period, demonstrating the chemical complexity and dynamics of the RDE. Transcriptomics was used to further elucidate the distinct molecular mechanisms of RDE and CYN. They act diversely in terms of cytotoxicity, involving oxidative stress and response, protein content, and energy metabolism, and demonstrate distinct modes of action in neurofunctions. In essence, this study underscores the distinct toxicity mechanisms of RDE and CYN and emphasizes the necessity for context- and objective-specific toxicity assessments, advocating nuanced approaches to evaluate the ecological and health implications of cyanotoxins, thereby contributing to the precision of environmental risk assessments.

Mechanochromic Polymer Film with High Sensitivity toward Tensile Strain by the Post-Curing Ring-Closure Induced Pre-Stretching.

Mechanochromic materials have received broad research interests recently, owing to its ability to monitor the in situ stress/strain in polymer materials in a straightforward way. However, one major setback that hinders the practical application of these materials is their low sensitivity toward tensile strain. Here a new strategy for pre-stretching of the mechanochromic agent in a polymer film on the molecular scale, which can effectively enhance the mechanochromic sensitivity of a polymer film toward tensile strain, is shown. In situ fluorescent measurement during tensile test shows an early activation of the mechanochromic agent at tensile strain as low as 50%. The pre-stretching effect is realized by first inducing ring-opening of the mechanochromic agent by molecular functionalization, and then compelling the ring-closure process in the cured film by elevated temperature. This post-curing ring-closure process will result in pre-stretched mechanochromic agent in a crosslinked network. The mechanism for mechanochromic activation of polymer films with different composition is elaborated by visco-elastic measurements, and the effect of pre-stretching is further confirmed by films with other compositions. Combined with the simplicity of the method developed, this work could offer an alternative strategy to enhance the sensitivity of different mechanochromic agents toward tensile strain.

Development and validation of a novel prognostic lncRNA signature based on the APOBEC3 family genes in gastric cancer.

Introduction: Gastric Cancer (GC) refers to a prevalent malignant cancer accompanied by a weak prognosis. The APOBEC3 family genes and lncRNAs are linked with cancer progression. Nevertheless, there is still a scarcity of data concerning the prognostic value of APOBEC3-related lncRNAs in GC. Methods: We extracted the data from GC samples, including transcriptome as well as clinical data, obtained from the TCGA database. Then, we screened for lncRNAs that were correlated with the APOBEC3 family genes and constructed an APOBEC3-related lncRNA prognostic signature (LPS) by utilizing univariate Cox and lasso regression analysis. Furthermore, we validated our constructed signature and evaluated it thoroughly, including analysis of its function, immunity, mutations, and clinical applications via multiple methods, including Metascape, GSEA, and analyses including TIC and TME, immune checkpoints, CNV and SNPs, Kaplan-Meier survival curves, nomogram, decision tree and drug prediction analysis. Finally, we overexpressed LINC01094 to evaluate the impacts on the proliferation as well as migration with regards to KATO-2 cells. Results: We selected eight lncRNAs for our APOBEC3-related LPS, which is demonstrated as a valuable tool in predicting the individual GC patients' prognosis. Subsequently, we segregated the samples into subgroups of high-as well as low-risk relying on the risk score with regards to APOBEC3-related LPS. By performing functional analysis, we have shown that immune-as well as tumor-related pathways were enriched in high- and low-risk GC patients. Furthermore, immune analysis revealed a robust correlation between the APOBEC3-related LPS and immunity. We found that immune checkpoints were significantly associated with the APOBEC3-related LPS and were greatly exhibited in GC tumor and high-risk samples. Mutational analysis suggested that the mutational rate was greater in low-risk samples. Furthermore, we predicted small molecular drugs displayed greater sensitivity in patients categorized as high-risk. Moreover, the immune response was also better in high-risk patients. Of these drugs, dasatinib was significant in both methods and might be considered a potential novel drug for treating high-risk GC patients. Finally, we found that LINC01094 has the potential to enhance the migration, proliferation as well as inhibit apoptosis of KATO-2 in GC cells. And Dasatinib has an inhibitory effect on the migration as well as proliferation in GC cells. Conclusion: We created a novel APOBEC3-related LPS in predicting the prognosis with regards to individual GC patients. Importantly, this APOBEC3-related LPS was closely associated with immunity and might guide clinical treatment.

Rational Design of an In-Situ Polymer-Inorganic Hybrid Solid Electrolyte Interphase for Realising Stable Zn Metal Anode under Harsh Conditions.

The in-depth understanding of the composition-property-performance relationship of solid electrolyte interphase (SEI) is the basis of developing a reliable SEI to stablize the Zn anode-electrolyte interface, but it remains unclear in rechargeable aqueous zinc ion batteries. Herein, a well-designed electrolyte based on 2 M Zn(CF3SO3)2-0.2 M acrylamide-0.2 M ZnSO4 is proposed. A robust polymer (polyacrylamide)-inorganic (Zn4SO4(OH)6.xH2O) hybrid SEI is in situ constructed on Zn anodes through controllable polymerization of acrylamide and coprecipitation of SO4 2- with Zn2+ and OH-. For the first time, the underlying SEI composition-property-performance relationship is systematically investigated and correlated. The results showed that the polymer-inorganic hybrid SEI, which integrates the high modulus of the inorganic component with the high toughness of the polymer ingredient, can realize high reversibility and long-term interfacial stability, even under ultrahigh areal current density and capacity (30 mA cm-2~30 mAh cm-2). The resultant Zn||NH4V4O10 cell also exhibits excellent cycling stability. This work will provide a guidance for the rational design of SEI layers in rechargeable aqueous zinc ion batteries.

Combined methods elucidate the multi-organ toxicity of cylindrospermopsin (CYN) on Daphnia magna.

Global water bodies are now at risk from inevitable cyanobacterial blooms and their production of multiple cyanotoxins, in particular cylindrospermopsin (CYN). However, research on the CYN toxicity and its molecular mechanisms is still limited, whilst the responses of aquatic species against CYN are uncovered. By integrating behavioral observations, chemical detections and transcriptome analysis, this study demonstrated that CYN exerted multi-organ toxicity to model species, Daphnia magna. The present study confirmed that CYN could cause protein inhibition by undermining total protein contents, and altered the gene expression related to proteolysis. Meantime, CYN induced oxidative stress by increasing reactive oxygen species (ROS) level, decreasing the glutathione (GSH) concentration, and interfered with protoheme formation process molecularly. Neurotoxicity led by CYN was solidly determined by abnormal swimming patterns, reduced acetylcholinesterase (AChE), and downward expression of muscarinic acetylcholine receptor (CHRM). Importantly, for the first time, this research determined CYN directly interfered with energy metabolism in cladocerans. CYN distinctively reduced filtration and ingestion rate by targeting on heart and thoracic limbs, which declined the energy intake, and could be further displayed by the reduction of motional strength and the trypsin concentration. These phenotypic alterations were supported by transcriptomic profile, including the down-regulation of oxidative phosphorylation and ATP synthesis. Moreover, CYN was speculated to trigger the self-defense responses of D. magna, known as "abandon-ship" by moderating lipid metabolism and distribution. This study, overall, comprehensively demonstrated the CYN toxicity and the responses of D. magna against it, which is of great significance to the advancements of CYN toxicity knowledge.

Force-reversible chemical reaction at ambient temperature for designing toughened dynamic covalent polymer networks.

Force-reversible C-N bonds, resulting from the click chemistry reaction between triazolinedione (TAD) and indole derivatives, offer exciting opportunities for molecular-level engineering to design materials that respond to mechanical loads. Here, we displayed that TAD-indole adducts, acting as crosslink points in dry-state covalently crosslinked polymers, enable materials to display reversible stress-responsiveness in real time already at ambient temperature. Whereas the exergonic TAD-indole reaction results in the formation of bench-stable adducts, they were shown to dissociate at ambient temperature when embedded in a polymer network and subjected to a stretching force to recover the original products. Moreover, the nascent TAD moiety can spontaneously and immediately be recombined after dissociation with an indole reaction partners at ambient temperature, thus allowing for the adjustment of the polymer segment conformation and the maintenance of the network integrity by force-reversible behaviors. Overall, our strategy represents a general method to create toughened covalently crosslinked polymer materials with simultaneous enhancement of mechanical strength and ductility, which is quite challenging to achieve by conventional chemical methods.

A Toughening and Anti-Counterfeiting Benzotriazole-Based High-Performance Polymer Film Driven by Appropriate Intermolecular Coordination Force.

It is of great significance to circumvent the inherent trade-off between strength and extensibility for epoxy resins. Herein dynamic Cu-benzotriazole cross-links are incorporated, as the appropriate intermolecular coordination interaction, into high performance epoxy networks, and the resulting epoxy resins exhibits outstanding thermal stability and mechanical properties, their strength and extensibility are simultaneously improved. Additionally, local manipulation of coordination crosslinking confers the film with anti-counterfeiting function.

Unprecedented toughening high-performance polyhexahydrotriazines constructed by incorporating point-face cation-π interactions in covalently crosslinked networks and the visual detection of tensile strength.

We described a new concept for the design of high-performance supramolecular thermosets by incorporating point-face cation-π interactions in covalently crosslinked networks. Our findings showed an unprecedented increase in tensile strength and extensibility at once, a previously unknown behavior for stiff high performance polymers.

Cation-π induced lithium-doped conjugated microporous polymer with remarkable hydrogen storage performance.

A cation-π induced lithium-doped conjugated microporous polymer, Li+-PTAT, was constructed. It was proved that the point to face cation-π interactions between Li+ and indole can endow the resulting Li+-PTAT with high Li+ content and without agglomeration, which further leads to its encouraging hydrogen storage capacity.

Renewable 4-HIF/NaOH aerogel for efficient methylene blue removal via cation-π interaction induced electrostatic interaction.

A novel porous organic material 4-hydroxyindole-formaldehyde/NaOH (4-HIF/NaOH) aerogel was prepared via a facile polymerization, soaking in NaOH aqueous solution and ambient drying method. 4-HIF/NaOH aerogel porous polymer networks with high surface area have been applied as efficient adsorbents to remove methylene blue from wastewater via synergistic effects of cation-π interaction induced electrostatic interaction, electrostatic interaction and π-π interaction. The adsorption capacity calculated by adsorption isotherms at 303 K was 1016.9 mg g-1 which is higher than those observed for methylene blue on other aerogels and most other materials. Furthermore, the methylene blue loaded 4-HIF aerogel can easily be regenerated with 0.1 M HCl solution and ethanol wash, retaining over 75% of the adsorption capacity after recycling five times.

A recyclable hydroxyl functionalized polyindole hydrogel for sodium hydroxide extraction via the synergistic effect of cation-π interactions and hydrogen bonding.

We have successfully constructed a new type of recyclable indole-based hydrogel, which exhibited highly effective extraction behavior for hydroxide via the synergistic effect of cation-π interactions and hydrogen bonds. More interestingly, the absorption performance could be visually detected by taking advantage of the color altering effect of the host-guest interactions.