Sustainable upcycling of mixed spent cathodes to a high-voltage polyanionic cathode material.

Sustainable battery recycling is essential for achieving resource conservation and alleviating environmental issues. Many open/closed-loop strategies for critical metal recycling or direct recovery aim at a single component, and the reuse of mixed cathode materials is a significant challenge. To address this barrier, here we propose an upcycling strategy for spent LiFePO4 and Mn-rich cathodes by structural design and transition metal replacement, for which uses a green deep eutectic solvent to regenerate a high-voltage polyanionic cathode material. This process ensures the complete recycling of all the elements in mixed cathodes and the deep eutectic solvent can be reused. The regenerated LiFe0.5Mn0.5PO4 has an increased mean voltage (3.68 V versus Li/Li+) and energy density (559 Wh kg-1) compared with a commercial LiFePO4 (3.38 V and 524 Wh kg-1). The proposed upcycling strategy can expand at a gram-grade scale and was also applicable for LiFe0.5Mn0.5PO4 recovery, thus achieving a closed-loop recycling between the mixed spent cathodes and the next generation cathode materials. Techno-economic analysis shows that this strategy has potentially high environmental and economic benefits, while providing a sustainable approach for the value-added utilization of waste battery materials.

Multimodal Mass Spectrometry Identifies a Conserved Protective Epitope in S. pyogenes Streptolysin O.

An important element of antibody-guided vaccine design is the use of neutralizing or opsonic monoclonal antibodies to define protective epitopes in their native three-dimensional conformation. Here, we demonstrate a multimodal mass spectrometry-based strategy for in-depth characterization of antigen-antibody complexes to enable the identification of protective epitopes using the cytolytic exotoxin Streptolysin O (SLO) from Streptococcus pyogenes as a showcase. We first discovered a monoclonal antibody with an undisclosed sequence capable of neutralizing SLO-mediated cytolysis. The amino acid sequence of both the antibody light and the heavy chain was determined using mass-spectrometry-based de novo sequencing, followed by chemical cross-linking mass spectrometry to generate distance constraints between the antibody fragment antigen-binding region and SLO. Subsequent integrative computational modeling revealed a discontinuous epitope located in domain 3 of SLO that was experimentally validated by hydrogen-deuterium exchange mass spectrometry and reverse engineering of the targeted epitope. The results show that the antibody inhibits SLO-mediated cytolysis by binding to a discontinuous epitope in domain 3, likely preventing oligomerization and subsequent secondary structure transitions critical for pore-formation. The epitope is highly conserved across >98% of the characterized S. pyogenes isolates, making it an attractive target for antibody-based therapy and vaccine design against severe streptococcal infections.

Increased tumor-infiltrating plasmacytoid dendritic cells express high levels of PD-L2 and affect CD8+ T lymphocyte infiltration in human laryngeal squamous cell carcinoma.

The infiltration and prognostic significance of tumor-infiltrating plasmacytoid dendritic cells (TI-pDC) have been elucidated in various human solid cancers. However, the infiltrating patterns and functional importance of TI-pDC in laryngeal squamous cell carcinoma (LSCC) remain unknown. In this study, flow cytometric analyses were conducted to characterize the infiltration of dendritic cells and T lymphocytes, along with their respective subgroups in tumor tissues (TT), para-carcinoma tissues (PT), and peripheral blood (PB) from LSCC patients. Immunohistochemical staining for CD4 and CD8, as well as immunofluorescence staining for CD123, were performed on serial tissue sections to investigate the co-localization of TI-pDC and tumor-infiltrating T lymphocytes (TIL) within the tumor microenvironment (TME). Our results demonstrated significantly lower percentages of all three DC subsets in PB compared to TT and PT. Notably, the pDC percentage was markedly higher in TT than in PT. Moreover, TI-pDC percentage was significantly elevated in N+ stage patients compared to those with N0 stage. The results of survival analysis consistently demonstrated that high levels of TI-pDC infiltration were indicative of a poor prognosis. Further investigation revealed a significant negative correlation between TI-pDC and CD8+ TILs; notably, pDCs expressed an inhibitory surface molecule PD-L2 rather than PD-L1 within PT. Collectively, our findings suggest that increased TI-pDC is associated with adverse outcomes in LSCC patients while exhibiting an inhibitory phenotype that may play a crucial role in suppressing CD8+ TILs within LSCC tumors. These results highlight the potential therapeutic strategy targeting PD-L2+ pDCs for immunotherapies against LSCC.

Quantitative analysis of the morphing wing mechanism of raptors: Bionic design of Falco Peregrinus wing skeleton.

The wing is one of the most important parts of a bird's locomotor system and is the inspiration origination for bionic wing design. During wing motions, the wing shape is closely related to the rotation angles of wing bones. Therefore, the research on the law of bone movement in the process of wing movement can be good guidance for the design of the bionic morphing wing. In this paper, the skeletal posture of the peregrine falcon wing during the extension/flexion is studied to obtain critical data on skeletal posture. Since an elbow joint and a wrist joint rotate correlatively to drive a wing to flex/extend, the wing skeleton is simplified as a four-bar mechanism in this paper. The degree of reproduction of wing skeleton postures was quantitatively analyzed using the four-bar mechanism model, and the bionic wing skeleton was designed. It is found that the wing motions have been reproduced with high precision.

The hinge-engineered IgG1-IgG3 hybrid subclass IgGh47 potently enhances Fc-mediated function of anti-streptococcal and SARS-CoV-2 antibodies.

Streptococcus pyogenes can cause invasive disease with high mortality despite adequate antibiotic treatments. To address this unmet need, we have previously generated an opsonic IgG1 monoclonal antibody, Ab25, targeting the bacterial M protein. Here, we engineer the IgG2-4 subclasses of Ab25. Despite having reduced binding, the IgG3 version promotes stronger phagocytosis of bacteria. Using atomic simulations, we show that IgG3's Fc tail has extensive movement in 3D space due to its extended hinge region, possibly facilitating interactions with immune cells. We replaced the hinge of IgG1 with four different IgG3-hinge segment subclasses, IgGhxx. Hinge-engineering does not diminish binding as with IgG3 but enhances opsonic function, where a 47 amino acid hinge is comparable to IgG3 in function. IgGh47 shows improved protection against S. pyogenes in a systemic infection mouse model, suggesting that IgGh47 has promise as a preclinical therapeutic candidate. Importantly, the enhanced opsonic function of IgGh47 is generalizable to diverse S. pyogenes strains from clinical isolates. We generated IgGh47 versions of anti-SARS-CoV-2 mAbs to broaden the biological applicability, and these also exhibit strongly enhanced opsonic function compared to the IgG1 subclass. The improved function of the IgGh47 subclass in two distant biological systems provides new insights into antibody function.

Fast Li Replenishment Channels-Assisted Recycling of Degraded Layered Cathodes with Enhanced Cycling Performance and Thermal Stability.

The direct recycling of cathode materials in lithium-ion batteries is important for environmental protection and resource conservation. The key regeneration processes are composition replenishment and atom rearrangement, both of which depend on the migration and diffusion of atoms. However, for the direct recycling of degraded LiNi0.5 Co0.2 Mn0.3 O2 (D-NCM523) cathode, the irreversible phase transitions that accumulate during the long-term cycles block the Li diffusion channels with a high diffusion energy barrier, making it difficult to fully repair the layered structure and resulting in rapid capacity decay. To address the challenge, fast Li replenishment channels are rebuilt to regulate the surface phase and effectively assist the regeneration process with a reduced energy barrier. This method reduces the amount of Li supplement by >75% and shortens the sintering time (only 2 h) to fully regenerate D-NCM523, compared to general direct recycling methods. The regenerated NCM523 (LCMB-NCM523) exhibits a satisfactory repaired specific capacity of 160 mAh g-1 and excellent cycling stability, retaining 78% of its capacity after 300 cycles. In addition, LCMB-NCM523 is recycled with improved thermal decomposition peak temperature and enables 200 cycles even at 60 °C, greatly improving safety. This work proposes a promising way for the large-scale direct regeneration of layered cathodes.

Prognostic significance and immune escape implication of tumor-infiltrating neutrophil plasticity in human head and neck squamous cell carcinoma.

Tumor-infiltrating neutrophils play a crucial role in the progression of head and neck squamous cell carcinoma (HNSCC). Here, we aimed to statistically quantify the plasticity of HNSCC-infiltrating N2/N1 neutrophils and examine its impacts on survival and immune infiltration landscape. A retrospective study of 80 patients who underwent curative surgical resection for HNSCC between 2014 and 2017 was conducted in this study. HNSCC-infiltrating neutrophil phenotypes were classified using immunofluorescence staining, and the N2/N1 neutrophil plasticity was evaluated via the ratio of N2/N1 neutrophils. We then assessed the correlations between N2/N1 neutrophil plasticity, clinicopathological characteristics, and immune infiltration landscape using rigorous statistical methods. Infiltration variations of N1 and N2 neutrophils were observed between the tumor nest (TN) and tumor stroma (TS), with TN exhibiting higher N2 neutrophil infiltration and lower N1 neutrophil infiltration. High ratios of N2/N1 neutrophils were correlated with advanced TNM stage, large tumor size and invasion of adjacent tissue. High infiltration of N2 neutrophils was associated with decreased overall and relapse-free survival, which were opposite for N1 neutrophils. The independent prognostic role of N2/N1 neutrophil plasticity, particularly within the TN region, was confirmed by multivariate analyses. Moreover, the ratio of N2/N1 neutrophils within the TN region showed correlations with high CD8+ T cells infiltration and low FOXP3+ Tregs infiltration. We identify HNSCC-infiltrating N2/N1 neutrophil plasticity as a crucial prognostic indictor which potentially reflects the tumor microenvironment (TME) and immune escape landscape within HNSCC tissues. Further investigations and validations may provide novel therapeutic strategies for personalized immunomodulation in HNSCC patients.

The role of physical literacy and mindfulness on health-related quality of life among college students during the COVID-19 pandemic.

This study aimed to examine the role played by the physical literacy and mindfulness in the health-related quality of life (QoL) of college students. In early 2022, 24,236 college students from three universities in southern China were recruited in the study. R software and the lavvan package was utilized to build the structural equation model. The measurement model was composed of three latent factors (physical literacy, mindfulness, and quality of life) and 16 observed variables in total. The results of the measurement model indicated goodness fit with p > .05 in Chi-square result, and GFI = .92. In addition, the comparative fit index (.92), Tucker-Lewis index (.91), root-mean-square error of approximation (.07), and root of mean square residual (.11) were in accord with the cutoff model-fit criteria. The results confirm that physical literacy and mindfulness can play a significant and positive role in the structural equation model of quality of life. In addition, this study provides initial evidence that mindfulness and physical literacy could potentially buffer declines in student QoL during the COVID-19 pandemic. Moreover, this study is the first to develop a structural equation model of QoL with multiple indicators, making it a strong addition to existing research on QoL during a pandemic.

Isolation of tumor stem-like cells from primary laryngeal squamous cell carcinoma cells (FD-LS-6).

The development of efficient treatments for laryngeal squamous cell carcinoma (LSCC) is hindered by the lack of applicable tumor cell lines and animal models of the disease, especially those related to cancer stem-like cells (CSCs). CSCs play critical roles in tumor propagation and pathogenesis whereas no CSCs lines have been developed to date. In this study, we establish an LSCC cell line (FD-LS-6) from primary LSCC tumor tissue (not experienced single-cell cloning) and adapted a culturing condition for the expansion of potential stem cells (EPSCs) to isolate CSCs from FD-LS-6. We successfully derived novel CSCs and named them as LSCC sphere-forming cells (LSCSCs) which were subsequently characterized for their CSC properties. We showed that LSCSCs shared many properties of CSCs, including CSC marker, robust self-renewal capacity, tumorigenesis ability, potential to generate other cell types such as adipocytes and osteoblasts, and resistance to chemotherapy. Compared to parental cells, LSCSCs were significantly more potent in forming tumors in vivo in mice and more resistant to chemotherapy. LSCSCs have higher expressions of epithelial-mesenchymal transition proteins and chemotherapy resistance factors, and exhibit an activated COX2/PEG2 signaling pathway. Altogether, our work establishes the first CSCs of LSCC (FD-LS-6) and provides a tool to study tumorigenesis and metastasis of LSCC and help the development of anticancer therapies.

A Multifunctional Amino Acid Enables Direct Recycling of Spent LiFePO4 Cathode Material.

Lithium iron phosphate (LiFePO4 , LFP) batteries are extensively used in electric vehicles and energy storage due to their good cycling stability and safety. However, the finite service life of lithium-ion batteries leads to significant amounts of retired LFP batteries, urgently required to be recycled by environmentally friendly and effective methods. Here, a direct regeneration strategy using natural and low-cost L-threonine as a multifunctional reductant is proposed. The hydroxyl groups and amino groups in L-threonine act as electron donors and nitrogen sources, respectively. The reductive environment created by L-threonine not only aids in converting the degraded FePO4 phase back to a single LFP phase but also facilitates the elimination of detrimental Li-Fe anti-site defects; thus, reconstructing fast Li+ diffusion channels. Meanwhile, N atoms derived from amino groups are able to dope into carbon layers, generating more active sites and enhancing the conductive properties of LFP particles. The regenerated LFP shows great electrochemical performance with a discharge capacity of 147.9 mAh g-1 at 1 C and a capacity retention of 86% after 500 cycles at 5 C. Further, this approach is also feasible for LFP black mass sourced from practical industrial dismantling lines, providing considerable prospects for the large-scale recycling of LFP batteries.

What is esports? A systematic scoping review and concept analysis of esports.

This study conducted a systematic scoping review to collect definitions and explanations of esports and its related concepts in the existing literature. A thematic coding approach was used to screen possible disagreements and issues between the different characteristics of esports as presented in the existing definitions. Based on a critical discussion, the results of the coding were combined with the objective facts of the current esports industry and theories from similar fields to reconstruct the construction of an esports definition. In addition, the relationship between esports and its related concepts was discussed based on the proposed esports definition structure. The proposed esports criteria can help avoid misunderstandings and confusion in future studies regarding the research subjects related to esports and propose standardized usage of relevant terms in the field of esports research.

Perioperative predictors of outcome of hepatectomy for HBV-related hepatocellular carcinoma.

Hepatitis B virus (HBV) is identified as a major risk factor for hepatocellular carcinoma (HCC), resulting in so-called hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC). Hepatectomy for HCC is acknowledged as an efficient treatment strategy, especially for early HCC. Furthermore, patients with advanced HCC can still obtain survival benefits through surgical treatment combined with neoadjuvant therapy, adjuvant therapy, transcatheter arterial chemoembolization, and radiofrequency ablation. Therefore, preoperative and postoperative predictors of HBV-related HCC have crucial indicative functions for the follow-up treatment of patients with feasible hepatectomy. This review covers a variety of research results on preoperative and postoperative predictors of hepatectomy for HBV-related HCC over the past decade and in previous landmark studies. The relevant contents of Hepatitis C virus-related HCC, non-HBV non-HCV HCC, and the artificial intelligence application in this field are briefly addressed in the extended content. Through the integration of this review, a large number of preoperative and postoperative factors can predict the prognosis of HBV-related HCC, while most of the predictors have no standardized thresholds. According to the characteristics, detection methods, and application of predictors, the predictors can be divided into the following categories: 1. serological and hematological predictors, 2. genetic, pathological predictors, 3. imaging predictors, 4. other predictors, 5. analysis models and indexes. Similar results appear in HCV-related HCC, non-HBV non-HCV HCC. Predictions based on AI and big biological data are actively being applied. A reasonable prediction model should be established based on the economic, health, and other levels in specific countries and regions.

Relationship among positive self-esteem, physical literacy, and physical activity in college students: a study of a mediation model.

Background: In light of the substantial decline in physical activity during college years, this study aims to examine the relationship between positive self-esteem, physical literacy, and physical activity in order to investigate the mechanisms for improving physical activity in college students and to provide a foundation for future interventions. Methods: A cross-sectional study design was employed in this study. A total of 5,184 Participants, aged between 17 and 21 years (M = 18.97, SD = 1.10), completed the Positive Version of Rosenberg Self-esteem Scales, Perceived Physical Literacy Instruments, and the International Physical Activity Questionnaires. A mediation model was utilized to explore the associations among the three concepts. Results: The three regression models were as follows: Physical literacy = 18.03 + 0.98 *Self-esteem, Physical activity = 43.23 + 0.16 *Self-esteem, and Physical activity = 28.18 + 0.11 *Physical literacy. Positive self-esteem, physical literacy, and physical activity were significantly linked with each other. Physical literacy mediated 26.93% of the effect, indicating a partial mediator in the relationship between positive self-esteem and physical activity. Conclusion: The mediating effect of physical literacy on the relationship between positive self-esteem and physical activity was identified. Our findings support the development of positive self-esteem and physical literacy in college physical education curricula as part of an overall program to address students' physical inactivity at school and in the future. This study provides a new intervention perspective for improving physical inactivity in college students.

Confounded association between proton pump inhibitor use and risk of biliary tract cancer: Result from three cohorts.

Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.

Recent advances of three-dimensional bioprinting technology in hepato-pancreato-biliary cancer models.

Hepato-pancreato-biliary (HPB) cancer is a serious category of cancer including tumors originating in the liver, pancreas, gallbladder and biliary ducts. It is limited by two-dimensional (2D) cell culture models for studying its complicated tumor microenvironment including diverse contents and dynamic nature. Recently developed three-dimensional (3D) bioprinting is a state-of-the-art technology for fabrication of biological constructs through layer-by-layer deposition of bioinks in a spatially defined manner, which is computer-aided and designed to generate viable 3D constructs. 3D bioprinting has the potential to more closely recapitulate the tumor microenvironment, dynamic and complex cell-cell and cell-matrix interactions compared to the current methods, which benefits from its precise definition of positioning of various cell types and perfusing network in a high-throughput manner. In this review, we introduce and compare multiple types of 3D bioprinting methodologies for HPB cancer and other digestive tumors. We discuss the progress and application of 3D bioprinting in HPB and gastrointestinal cancers, focusing on tumor model manufacturing. We also highlight the current challenges regarding clinical translation of 3D bioprinting and bioinks in the field of digestive tumor research. Finally, we suggest valuable perspectives for this advanced technology, including combination of 3D bioprinting with microfluidics and application of 3D bioprinting in the field of tumor immunology.

Nitrogen addition increases topsoil carbon stock in an alpine meadow of the Qinghai-Tibet Plateau.

Soil carbon (C) sequestration plays a critical role in mitigating climate change. Nitrogen (N) deposition greatly affects soil C dynamics by altering C input and output. However, how soil C stocks respond to various forms of N input is not well clear. This study aimed to explore the impact of N addition on soil C stock and to elucidate the underlying mechanisms in an alpine meadow on the eastern Qinghai-Tibet Plateau. The field experiment involved three N application rates and three N forms, using a non-N treatment as a control. After six years of N addition, the total C (TC) stocks in the topsoil (0-15 cm) were markedly increased by an average of 12.1 %, with a mean annual rate of 20.1 ‰, and no difference was found between the N forms. Irrespective of rate or form, N addition significantly increased the topsoil microbial biomass C (MBC) content, which was positively correlated with mineral-associated and particulate organic C content and was identified as the most important factor that affecting the topsoil TC. Meanwhile, N addition significantly increased the aboveground biomass in the years with moderate precipitation and relatively high temperature, which leads to higher C input into soils. Owing to decreased pH and/or activities of ß-1,4-glucosidase (ßG) and cellobiohydrolase (CBH) in the topsoil, organic matter decomposition was most likely inhibited by N addition, and this inhibiting effect varied under different N forms. Additionally, TC content in the topsoil and subsoil (15-30 cm) exhibited parabolic and positive linear relationship with the topsoil dissolved organic C (DOC) content, respectively, indicating that DOC leaching might be an important influencing factor for soil C accumulation. These findings improve our understanding of how N enrichment affects C cycles in alpine grassland ecosystems and suggest that soil C sequestration in alpine meadows probably increases with N deposition.

The use of IVF/ICSI and risk of postpartum hemorrhage: A retrospective cohort study of 153,765 women in China.

Objective: Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity and mortality. Identifying women who are at high risk of PPH is crucial for implementing early preventive and interventive strategies. This study aimed to examine whether there is an association between the use of in vitro fertilization (IVF) /intracytoplasmic sperm injection (ICSI) and increased risk of PPH. Method: This retrospective cohort study was conducted using medical record data from women who delivered at a tertiary hospital in Shanghai, China, between January 1, 2013 and April 30, 2019. Logistic regression analysis was used to estimate the associations between the use of IVF/ICSI and the risk of PPH. Results: A total of 153,765 pregnant women were included, of which 6,484 conceived through IVF/ICSI and147,281 conceived naturally. The incidence of PPH was 1.9% in this cohort. The incidence of PPH in women who conceived through IVF/ICSI was significantly higher than those in women who conceived naturally (3.4% vs. 1.7%, p < 0.01). The use of IVF/ICSI was associated with an increase in the amount of postpartum blood loss. Compared to women who conceived naturally, the average amount of postpartum blood loss increased by 42.1 mL (ß = 42.1, 95% CI, 38.2-46.0) for women who conceived through IVF/ICSI. In addition, women who conceived through IVF/ICSI were at higher risk of maternal PPH. The adjusted odds ratio (OR) of PPH in women who conceived through ART was 2.7 (OR = 2.7, 95% CI, 2.3-3.1). Conclusion: Our findings demonstrated that women who conceived through IVF/ICSI were at higher risk of PPH and suggested to obstetricians and midwives to identify and implement early preventative strategies for PPH among pregnant women who conceived through IVF/ICSI.

Separator with Nitrogen-Phosphorus Flame-Retardant for LiNix Coy Mn1- x - y O2 Cathode-Based Lithium-Ion Batteries.

With the pursuit of high-energy-density for lithium-ion batteries (LIBs), the hidden safety problems of batteries have gradually emerged. LiNix Coy Mn1- x - y O2 (NCM) is considered as an ideal cathode material to meet the urgent needs of high-energy-density batteries. However, the oxygen precipitation reaction of NCM cathode at high temperature brings serious safety concerns. In order to promote high-safety lithium-ion batteries, herein, a new type of flame-retardant separator is prepared using flame-retardant (melamine pyrophosphate, MPP) and thermal stable Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP). MPP takes the advantage of nitrogen-phosphorus synergistic effect upon the increased internal temperature of LIBs, including the dilution effect of noncombustible gas and the rapidly suppression of undesirable thermal runaway. The developed flame-retardant separators show negligible shrinkage over 200 °C and it takes only 0.54 s to extinguish the flame in the ignition test, which are much superior to commercial polyolefin separators. Moreover, pouch cells are assembled to demonstrate the application potential of PVDF-HFP/MPP separators and further verify the safety performance. It is anticipated that the separator with nitrogen-phosphorus flame-retardant can be extensively applied to various high-energy-density devices owing to simplicity and cost-effectiveness.

Prenylated dihydroflavones from the root barks of Morus alba.

Three new prenylated dihydroflavones, moralbaflavones A-C (1-3), together with four known ones (4a/4b, 5, and 6) were isolated from the root barks of Morus alba L. Their structures including the absolute configurations were determined by the analysis of HRMS, NMR, and ECD data. The neuroprotective properties of these prenylated dihydroflavones were screened at the concentration of 10 µM in the sodium nitroprusside-induced rat pheochromocytoma PC-12 cells, and the results showed moralbaflavone C (3) possessed significant neuroprotective activity, being more potent than the positive control edaravone.