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The electrochemical recycling nanoarchitectonics of graphene oxide from carbon fiber reinforced polymers (CFRPs) is a promising approach due to its economic and environmental benefits. However, the rapid degradation of the CFRP anode during the recycling process reduces its overall efficiency. Although previous studies have investigated the electrochemical oxidation of carbon fibers (CFs) and bonding of CFs to the matrix, few researchers have explicitly studied the electrochemical activity of CFs and the possible fracture caused by strong electrochemical reactions. To address this gap, this study investigates the degradation mechanism of CF anodes by analyzing changes in overall mechanical properties, hardness, elastic modulus, functional groups, and elemental composition of individual fibers. The experimental results demonstrate that the three-phase boundary region experiences the most severe degradation, primarily due to the number of oxygen-containing functional groups, which is the most important factor affecting the degree of degradation. This continuous decrease in the hardness and elastic modulus of individual fibers eventually leads to the fracture of CF anodes., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The global outbreaks of infectious diseases have significantly driven an imperative demand for rapid and accurate molecular diagnostics. Nucleic acid amplification tests (NAATs) feature high sensitivity and high specificity; however, the labor-intensive sample preparation and nucleic acid amplification steps remain challenging in order to carry out rapid and precision molecular diagnostics at home. This review discusses the advances and challenges of automatic solutions of sample preparation integrated with on-chip nucleic acid amplification for effective and accurate molecular diagnostics at home. The sample preparation methods of whole blood, urine, saliva/nasal swab, and stool on chip are examined. Then, the repurposable integrated sample preparation on a chip using various biological samples is investigated. Finally, the on-chip NAATs that can be integrated with automated sample preparation are evaluated. The user-friendly approaches with combined sample preparation and NAATs can be the game changers for next-generation rapid and precision home diagnostics., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Replication fork reversal safeguards genome integrity as a replication stress response. DNA translocases and the RAD51 recombinase catalyze reversal. However, it remains unknown why RAD51 is required and what happens to the replication machinery during reversal. We find that RAD51 uses its strand exchange activity to circumvent the replicative helicase, which remains bound to the stalled fork. RAD51 is not required for fork reversal if the helicase is unloaded. Thus, we propose that RAD51 creates a parental DNA duplex behind the helicase that is used as a substrate by the DNA translocases for branch migration to create a reversed fork structure. Our data explain how fork reversal happens while maintaining the helicase in a position poised to restart DNA synthesis and complete genome duplication.

Background: This study aimed to determine whether altered mRNA, long non-coding RNA, and circular RNA expression is related to hepatocellular carcinoma recurrence after liver transplantation., Methods: Five recurrent and 5 non-recurrent primary hepatocellular carcinoma samples were used to perform RNA sequencing. Then, differentially expressed mRNAs, differentially expressed long non-coding RNAs, and differentially expressed circular RNAs between recurrent group and non-recurrent group were identified. In addition, differentially expressed long non-coding RNA/differentially expressed circular RNA-differentially expressed mRNA co-expression network, and competing endogenous RNA (differentially expressed circular RNA/differentially expressed long non-coding RNA-miRNA-differentially expressed mRNA) regulatory network were constructed. Finally, real-time quantitative polymerase chain reaction was performed for verification., Results: Five hundred forty-one differentially expressed mRNAs, 239 differentially expressed long non-coding RNAs, and 16 differentially expressed circular RNAs in the recurrent group were obtained. Gene set enrichment analysis indicated that these differentially expressed mRNAs may affect hepatocellular carcinoma recurrence through multiple pathways, such as E2F, epithelial-mesenchymal transition, G2M, and oxidative phosphorylation. Then, 993 differentially expressed long non-coding RNA-differentially expressed mRNA co-expression pairs and 28 differentially expressed circular RNA/differentially expressed mRNA co-expression pairs were obtained. The competing endogenous RNA network contained 10 circular RNA-miRNA pairs, 12 long non-coding RNA-miRNA pairs, and 36 miRNA- mRNA pairs. Real-time quantitative polymerase chain reaction results showed the same expression trend as RNA-seq results., Conclusion: Our results reveal key mRNAs, long non-coding RNAs, and circular RNAs associated with recurrence in hepatocellular carcinoma patients after liver transplantation.

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent liver disorder. With the improvement in human living standards, the prevalence of NAFLD has been increasing in recent years. Endocrine-disrupting chemicals (EDCs) are a class of exogenous chemicals that simulate the effects of hormones in the body. There has been growing evidence regarding the potential effects of EDCs on liver health, especially in NAFLD. This paper aims to summarize the major EDCs that contribute to the growing burden of NAFLD and to raise public awareness regarding the hazards posed by EDCs with the objective of reducing the incidence of NAFLD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Chen, Wang, Cui, Liu, Liu, Zeng, Zhao, Dou and Cao.)

Inorganic nanomaterials such as graphene, black phosphorus, and transition metal dichalcogenides have attracted great interest in developing optoelectronic devices due to their efficient conversion between light and electric signals. However, the zero band gap nature, the unstable chemical properties, and the low electron mobility constrained their wide applications. Bismuth oxyselenide (Bi 2 O 2 Se) is gradually showing great research significance in the optoelectronic field. Here, we develop a bismuth oxyselenide/p-silicon (Bi 2 O 2 Se/p-Si) heterojunction and design a self-powered and broadband Bi 2 O 2 Se/p-Si heterojunction photodetector with an ultrafast response (2.6 μs) and low dark current (10 -10 A without gate voltage regulation). It possesses a remarkable detectivity of 4.43 × 10 12 cm Hz 1/2 W -1 and a self-powered photoresponse characteristic at 365-1550 nm (ultraviolet-near-infrared). Meanwhile, the Bi 2 O 2 Se/p-Si heterojunction photodetector also shows high stability and repeatability. It is expected that the proposed Bi 2 O 2 Se/p-Si heterojunction photodetector will expand the applications of Bi 2 O 2 Se in practical integrated circuits in the field of material science, energy development, optical imaging, biomedicine, and other applications.

Genotoxins cause nascent strand degradation (NSD) and fork reversal during DNA replication. NSD and fork reversal are crucial for genome stability and are exploited by chemotherapeutic approaches. However, it is unclear how NSD and fork reversal are triggered. Additionally, the fate of the replicative helicase during these processes is unknown. We developed a biochemical approach to study synchronous, localized NSD and fork reversal using Xenopus egg extracts and validated this approach with experiments in human cells. We show that replication fork uncoupling stimulates NSD of both nascent strands and progressive conversion of uncoupled forks to reversed forks. Notably, the replicative helicase remains bound during NSD and fork reversal. Unexpectedly, NSD occurs before and after fork reversal, indicating that multiple degradation steps take place. Overall, our data show that uncoupling causes NSD and fork reversal and elucidate key events that precede fork reversal., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Metal ions play vital roles in the electron transfer between biological molecules in humans, animals, and plants. However, the electron transfer between metal ions and nucleic acids and its impact on DNA-ion binding during DNA replication has been ignored. Here, we present a long-range quantum biological electron transfer (QBET) between DNA bases and metal ions and its selective function of DNA-ion binding in DNA replication. We discover biophysical DNA-ion binding and create biological filters that allow selective DNA replication by dual modulators of the valence and concentration of metal ions. QBET-based DNA replication filters provide powerful tools for ultrasensitive polymerase chain reaction (PCR) to selectively amplify target sequences with a discrete concentration window of metal ions; for example, Au 3+ exhibits a concentration window that is approximately 3 orders of magnitude lower than that of Na + . DNA-ion filters provide new perspectives into metal ion-mediated QBET in DNA replication and hold great potential in life sciences and medical applications.

Background: The aim of our study was to use the differentially expressed mRNAs (DEmRNAs) and differentially expressed miRNAs (DEmiRNAs) to illustrate the underlying mechanism of hypoxia in liver cancer., Methods: In this study, a cell model of hypoxia was established, and autophagy activity was measured with western blotting and transmission electron microscopy. The effect of hypoxia conditions on the invasion of liver cancer cell was evaluated. RNA sequencing was used to identify DEmRNAs and DEmiRNAs to explore the mechanism of hypoxia in liver cancer cells., Results: We found that autophagy activation was triggered by hypoxia stress and hypoxia might promote liver cancer cell invasion. In addition, a total of 407 shared DEmRNAs and 57 shared DEmiRNAs were identified in both HCCLM3 hypoxia group and SMMC-7721 hypoxia group compared with control group. Furthermore, 278 DEmRNAs and 24 DEmiRNAs were identified as cancer hypoxia-specific DEmRNAs and DEmiRNAs. Finally, we obtained 19 DEmiRNAs with high degree based on the DEmiRNA-DEmRNA interaction network. Among them, hsa-miR-483-5p, hsa-miR-4739, hsa-miR-214-3p and hsa-miR-296-5p may be potential gene signatures related to liver cancer hypoxia., Conclusions: Our study may help to understand the potential molecular mechanism of hypoxia in liver cancer., (© 2022. The Author(s).)

Edaravone, an antioxidant protective agent, has anti-cerebral ischemic reperfusion injury (CIRI) effects, but its anti-CIRI mechanism is unclear. The aim of this study is to investigate the anti-CIRI mechanism of edaravone based on the nuclear factor-E2-related factor 2 (Nrf2)/ferroportin (FPN) pathway that regulates ferroptosis-mediated cerebral ischemia-reperfusion injury. We evaluated the brain injury by constructing a middle cerebral artery occlusion and reperfusion (MCAO/R) model in rats. The results showed that cerebral infarct volume and neurological impairment scores were increased in cerebral ischemia-reperfusion rats, with impaired sensorimotor ability; furthermore, brain tissue glutathione (GSH) content was decreased, Fe 2+ , malondialdehyde (MDA) and lipide peroxide (LPO) content were increased, and the expression level of glutathione peroxidase 4 (GPX4), a key protein of ferroptosis, was also decreased. Meanwhile, the Nrf2 expression level was increased and the FPN expression level was decreased after cerebral ischemia-reperfusion, while the levels of interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, and myeloperoxidase (MPO) were increased. However, edaravone exhibited a protective effect on cerebral infarct and neurological and sensorimotor function in relevant tests. In addition, we also found that edaravone decreased the contents of Fe 2+ , MDA, and LPO in the brain tissue of MCAO/R rats and increased GSH content to inhibit ferroptosis. Furthermore, Western blot showed that after treatment with edaravone, the expression of Nrf2, GPX4, and FPN was up-regulated, the nuclear location of Nrf2 was increased, and the levels of inflammation-related indicators IL-6, IL-1β, TNF-α, and MPO were lower than in the MCAO/R group. Our results demonstrated that edaravone inhibits ferroptosis to attenuate CIRI, probably through the activation of the Nrf2/FPN pathway.

DNA replication always encounters numerous endogenous and exogenous stresses during the cell cycle. Measuring the cell responses to stress has primarily relied on cell survival and incorporation of radioactive dNTPs, which is limited in resolution. A higher resolution is required to monitor how replication and repair respond to these stresses. This protocol describes a procedure to monitor the length of new synthesized DNA in a single molecular resolution called DNA fiber assay. The fiber assay relies on labeling of nascent DNA with the nucleoside analog 5-Chloro-2'-deoxyuridine (CldU) and 5-Iodo-2'-deoxyuridine (IdU). We can visualize the labeled nascent DNA in single molecular resolution by immunostaining. By measuring labeled DNA length, the assay permits interrogation of replication speed at given conditions, end processing at the reversed fork, and fork restart after repair., Competing Interests: Competing interestsNo competing interests declared., (Copyright © 2021 The Authors; exclusive licensee Bio-protocol LLC.)

Objective To purify recombinant protein of human von Hippel-Lindau (VHL) and identify its function. Methods VHL gene sequence was amplified from human mammary cDNA using PCR and inserted into the prokaryotic expression vector pGEX-KG. Glutathione S-transferase-VHL (GST-VHL) recombinant plasmid we obtained was converted into BL21(DE3) sensitive bacteria to induce a small amount of GST-VHL protein. The expressed product was detected by SDS-PAGE and Western blot analysis. The recombinant protein was purified by GST beads and its function was verified by GST pull-down assay. Results The obtained recombinant plasmid could be successfully digested by double enzymes. Gene sequencing showed that the VHL sequence was correct and there was no mutation. The recombinant protein with approximately relative molecular mass (M r ) 56 000 was purified by converting recombinant plasmid to BL21(DE3) sensitive bacteria and inducing it in small quantities. GST pull-down assay verified that GST-VHL recombinant protein had the function of binding hypoxia inducible factor-1 α (HIF-1 α) in vitro. Conclusion GST-VHL recombinant protein is purified and can combine with HIF-1α protein in vitro.

In this work, a new method to tune the resonant frequency of microfabricated resonator using molecular layer-by-layer (LbL) self-assembly approach is demonstrated. By simply controlling the polymer concentration and the number of layers deposited, precisely tuning the frequency of microfabricated resonators is realized. Due to its selective deposition through specific molecular recognitions, such technique avoids the high-cost and complex steps of conventional semiconductor fabrications and is able to tune individual diced device. Briefly, film bulk acoustic resonator (FBAR) is used to demonstrate the tuning process and two types of LbL deposition methods are compared. The film thickness and morphology have been characterized by UV-vis reflection spectra, ellipsometer and AFM. As a result, the maximum resonant frequency shift of FBAR reaches more than 20 MHz, meaning 1.4% tunability at least. The minimum frequency shift is nearly 10 kHZ per bilayer, indicating 7 ppm tuning resolution. Pressure cooker test (PCT) is performed to evaluate the reliability of LbL coated FBAR. Furthermore, applications for wireless broadband communication and chemical sensors of LbL coated FBAR have been demonstrated.