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Domoic acid (DA) is a compound generated as a secondary metabolite during harmful algal blooms, has historically received attention as the potent neurotoxicity in marine environment. However, the aerobic degradation mechanism of DA and the DA-degrader remain largely unknown. Here, we revealed the mechanism of aerobic degradation of DA by a ubiquitous marine Pseudoalteromonas sp., and more importantly, we confirmed that the degradation of DA is mediated by biogenic reactive oxygen species (ROS), rather than direct enzyme-mediated as traditionally conceived. Results indicated that DA degradation was caused by biogenic O2- and OH, where DA underwent reactions of decarboxylation, hydroxylation, and oxidation to yield the detoxification terminal product. Besides, whole genome sequencing and RT-qPCR analysis revealed that the genes conferring to encoding leucine dehydrogenase (ldh) and Na+-translocated NADH-quinone oxidoreductase (nqrA, nqrF) are responsible for biogenic ROS production. Finally, we found through comparative proteomic analysis that biogenic ROS mediated the DA degradation may be prevalent in the environment. Overall, this work not only reveals aerobic biotransformation mechanism of DA, but also identifies a novel mechanism of DA degradation, which provides new perspective into the environmental fate of DA and the artificial bioremediation of DA.

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2D transitional metal selenide heterostructures are promising electrode materials for potassium-ion batteries (PIBs) owing to the large surface area, high mechanical strength, and short diffusion pathways. However, the cycling performance remains a significant challenge, particularly concerning the electrochemical conversion reaction. Herein, 2D Se-rich ZnSe/CoSe2@C heterostructured composite is fabricated via a convenient hydrothermal approach followed by selenization process, and then applied as high-performance anodes for PIBs. For example, the capacity delivered by the heterostructured composite is mainly contributed to the synergistic effect of conversion and alloy/de-alloy processes aroused by K+, where K+ may highly insert or de-insert into Se-rich ZnSe/CoSe2@C. The obtained electrode delivers an outstanding reversible charge capacity of 214 mA h g-1 at 1 A g-1 after 4000 cycles for PIBs, and achieves 262 mAh g-1 when coupled with a PTCDA cathode in the full cell. The electrochemical conversion mechanism of the optimized electrode during cycling is investigated through in situ XRD, Raman, and ex situ HRTEM. In addition, the heterostructured composite as anodes also displays excellent electrochemical performances for sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs). This work opens up a new window for investigating novel electrode materials with excellent capacity and long durability.

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Conversion and alloying-type transitional metal sulfides have attracted significant interests as anodes for Potassium-ion batteries (PIBs) and Sodium-ion batteries (SIBs) due to their high theoretical capacities and low cost. However, the poor conductivity, structural pulverization, and high-volume expansions greatly limit the performance. Herein, Co1-xS/ZnS hollow nanocube-like heterostructure decorated on reduced graphene oxide (Co1-xS/ZnS@rGO) composite is fabricated through convenient hydrothermal and post-heat vulcanization techniques. This unique composite can provide a more stable conductive network and shorten the diffusion length of ions, which exhibits a remarkable initial charge capacity of 638.5 mA h g-1 at 0.1 A g-1 for SIBs and 606 mA h g-1 at 0.1 A g-1 for PIBs, respectively; It is worth noting that the composite presents remarkable long stable cycle performance in PIBs, which initially delivered 274 mA h g-1 and sustained the charge capacity up to 245 mA h g-1 at high current density of 1 A g-1 after 2000 cycles. A series of in situ/ex situ detections and first principle calculations further validate the high potassium ions adsorption ability of Co1-xS/ZnS anode materials with high diffusion kinetics. This work will accelerate the fundamental construction of bimetallic sulfide hollow nanocubes heterostructure electrodes for energy storage applications.

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Anionic chemistry modulation represents a promising avenue to enhance the electrochemical performance and unlock versatile applications in cutting-edge energy storage devices. Herein, we propose a methodology that involves anionic chemistry of carbonate anions to tailor the electrochemical oxidation-reduction reactions of bismuth (Bi) electrodes, where the conversion energy barrier for Bi (0) to Bi (III) has been significantly reduced, endowing anionic full batteries with enhanced electrochemical kinetics and chemical self-charging property. The elaborately designed batteries with an air-switch demonstrate rapid self-recharging capabilities, recovering over 80 % of the electrochemical full charging capacity within a remarkably short timeframe of 1 hour and achieving a cumulative self-charging capacity of 5 Ah g-1. The aqueous self-charging battery strategy induced by carbonate anion, as proposed in this study, holds the potential for extending to various anionic systems, including seawater-based Cl- ion batteries. This work offers a universal framework for advancing next-generation multi-functional power sources.

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OBJECTIVES: Triple-negative breast cancer (TNBC) is characterized by significant heterogeneity, presenting a formidable challenge with a poor prognosis and a deficiency of efficacious treatment options. METHODS: In this comprehensive study, we investigated the multifaceted role of Microfibril-associated glycoprotein 2 (MFAP2) in TNBC using a combination of bioinformatics analysis involving Gene Expression Omnibus (GEO), OncoDB, UALCAN, Human Protein Atlas (HPA), TIMER, STRING, DAVID, and GSCA databases and in vitro experiments, such as cell culture, MFAP2 gene knockdown, RT-qPCR, western Blot, colony formation, Cell counting kit-8, and wound healing assays. RESULTS: Our findings demonstrated a significant up-regulation of MFAP2 mRNA in TNBC cell lines, emphasizing its potential as a diagnostic biomarker. Validation across multiple datasets further affirmed the elevated expression of MFAP2 in TNBC tissues, underscoring its prognostic relevance. Notably, our study revealed a correlation between MFAP2 expression and immune cell infiltration, suggesting its role in shaping the tumor microenvironment. STRING analysis unveiled interactions with proteins involved in elastic fibers and extracellular matrix constituents. Furthermore, KEGG pathway analysis highlighted enrichment in the TGF-beta signaling pathway, implicating MFAP2 in key cancer-related processes. Drug sensitivity analysis identified potential therapeutic targets, supporting MFAP2's utility in personalized treatment strategies. In vitro experiments corroborated the oncogenic impact of MFAP2, demonstrating its influence on TNBC cell proliferation and migration. CONCLUSION: These comprehensive findings position MFAP2 as a promising biomarker and therapeutic target in TNBC, offering valuable insight for future research and clinical application.

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The catalytic process of Li2S formation is considered a key pathway to enhance the kinetics of lithium-sulfur batteries. Due to the system's complexity, the catalytic behavior is uncertain, posing significant challenges for predicting activity. Herein, we report a novel cascaded dual-cavity nanoreactor (NiCo-B) by controlling reaction kinetics, providing an opportunity for achieving hierarchical catalytic behavior. Through experimental and theoretical analysis, the multilevel structure can effectively suppress polysulfides dissolution and accelerate sulfur conversion. Furthermore, we differentiate the adsorption (B-S) and catalytic effect (Co-S) in NiCo-B, avoiding catalyst deactivation caused by excessive adsorption. As a result, the as-prepared battery displays high reversible capacity, even with sulfur loading of 13.2 mg cm-2 (E/S=4 µl mg-1), the areal capacity can reach 18.7 mAh cm-2.

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BACKGROUND: This study aimed to investigate the specific roles of the long non-coding RNA (lncRNA) proteasome 20S subunit beta 8 (PSMB8)-antisense RNA 1 (AS1)/microRNA (miR)-382-3p/branched-chain amino acid transaminase 1 (BCAT1) interaction network in gliomas. METHODS: Western blotting and quantitative reverse transcription-polymerase chain reaction were performed to assess the expression levels of lncRNA PSMB8-AS1, BCAT1, and miR-382-3p. Moreover, the cell proliferation, migration, and apoptosis were assessed using the cell counting kit-8, Transwell, and caspase-3 activity assays, respectively. The biological role of lncRNA PSMB8-AS1 in glioma was investigated in vivo using a xenograft mouse model. Additionally, the associations among lncRNA PSMB8-AS1, miR-382-3p, and BCAT1 were analyzed using dual-luciferase and RNA immunoprecipitation assays and bioinformatics analyses. RESULTS: Glioma cell lines and tissues exhibited overexpression of lncRNA PSMB8-AS1 and BCAT1 and low expression of miR-382-3p. Knockdown of PSMB8-AS1 remarkably repressed the tumor growth in vivo and the migration and proliferation of glioma cells in vitro. In contrast, knockdown of lncRNA PSMB8-AS1 increased the cell apoptosis. Mechanistically, PSMB8-AS1 directly targeted miR-382-3p. By sponging miR-382-3p, lncRNA PSMB8-AS1 stimulated the migration and proliferation of glioma cells and suppressed their apoptosis. Additionally, miR-382-3p directly targeted BCAT1. Inhibition of miR-382-3p reversed the antitumor effects of BCAT1 silencing on glioma progression. CONCLUSION: Our study revealed that lncRNA PSMB8-AS1 aggravated glioma malignancy by enhancing BCAT1 expression after competitively binding to miR-382-3p. Therefore, lncRNA PSMB8-AS1 may be a potential biomarker and therapeutic target for glioma treatment.

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Objective: The primary aim of this research is to investigate the predictive value of subdural effusion thickness in determining the progression of post-traumatic subdural effusion to chronic subdural hematoma. Studying this progression is crucial as it helps in early diagnosis and effective management of chronic subdural hematoma, which is a serious and life-threatening condition. This research is valuable and relevant for improving patient outcomes and reducing the associated risks and complications. Methods: We conducted a retrospective examination of the clinical data obtained from 124 patients who were treated for post-traumatic subdural effusion at our neurosurgery department between March 2017 and March 2021. The data collection process involved reviewing the patients' medical records, radiographic images, and follow-up visits. We used strict criteria for patient selection, including a confirmed diagnosis of post-traumatic subdural effusion, availability of follow-up data, and no prior history of chronic subdural hematoma. Patients who experienced a progression of subdural effusion to chronic subdural hematoma were assigned to the hematoma group (26 cases). In comparison, those who did not show such progression were categorized into the effusion group (98 cases). We endeavored to identify potential risk factors contributing to the progression from subdural effusion to chronic subdural hematoma. The predictive strengths of these risk factors were evaluated using receiver operating characteristic (ROC) curves. Results: There were no statistically significant disparities between the two groups in terms of gender, hypertension, COPD, and GCS scores (P > .05). However, significant differences were noted in the variables of age, tSAH, the location of subdural effusion, and subdural effusion thickness (P < .05). Multivariate logistic regression analysis disclosed age (1.213), tSAH (12.542), and subdural effusion thickness (1.786) as independent risk factors for the conversion of TSE to CSDH (P < .05). The ROC curve showed the AUC values of age, tSAH, and subdural effusion thickness for predicting CSDH to be 0.739, 0.670, and 0.820, respectively, with a combined AUC value of 0.942, thereby outperforming the individual tests. Conclusion: In patients suffering from post-traumatic subdural effusion, the thickness of the subdural effusion emerges as a strong predictor for its progression into a chronic subdural hematoma. Clinicians should be particularly cautious when the effusion thickness exceeds 10.7 mm, as the likelihood of transformation increases significantly. These findings have important implications for clinical practice and patient management, highlighting the need for prompt and effective treatment to prevent chronic complications.

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Sluggish sulfur redox kinetics and Li-dendrite growth are the main bottlenecks for lithium-sulfur (Li-S) batteries. Separator modification serves as a dual-purpose approach to address both of these challenges. In this study, the Co/MoN composite is rationally designed and applied as the modifier to modulate the electrochemical kinetics on both sides of the sulfur cathode and lithium anode. Benefiting from its adsorption-catalysis function, the decorated separators (Co/MoN@PP) not only effectively inhibit polysulfides (LiPSs) shuttle and accelerate their electrochemical conversion but also boost Li+ flux, realizing uniform Li plating/stripping. The accelerated LiPSs conversion kinetics and excellent sulfur redox reversibility triggered by Co/MoN modified separators are evidenced by performance, in-situ Raman detection and theoretical calculations. The batteries with Co/MoN@PP achieve a high initial discharge capacity of 1570 mAh g-1 at 0.2 C with a low decay rate of 0.39%, uniform Li+ transportation at 1 mA cm-2 over 800 h. Moreover, the areal capacity of 4.62 mAh cm-2 is achieved under high mass loadings of 4.92 mg cm-2. This study provides a feasible strategy for the rational utilization of the synergistic effect of composite with multifunctional microdomains to solve the problems of Li anode and S cathode toward long-cycling Li-S batteries.

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MnO2 has the advantages of low cost and abundant resources, so it is considered to be an important electrode material in zinc ion batteries. However, its practical application is still challenged by easy collapse and capacity loss. In this paper, a stable single crystal ß-MnO2 nanorod cathode material was prepared. When used as ZIBs cathode material, single crystal ß-MnO2 has high ionic diffusion kinetics and calculability. In this paper, we prepared single-crystal MnO2 through hydrothermal nanotechnology. By leveraging the benefits of the single-crystal structure, we optimized the structural stability, ion conductivity, surface reactions, and phase control of the cathode material, resulting in improved battery performance and cycle life. In the fabricated single-crystal MnO2 aqueous zinc-ion battery, the elimination of internal crystal faces in MnO2 leads to ordered lattice arrangement, enabling a more direct and unobstructed diffusion path for H+ ions within the lattice. This significantly enhances the ion conductivity of the cathode material, promoting the rate and efficiency of the battery's charge and discharge processes. Therefore, single-crystal MnO2 exhibits excellent cycling performance for zinc-ion storage in ZIBs, achieving a high specific capacity of 224.7 mA h g-1 after 250 cycles under a current density of 0.3 A g-1 , while maintaining a Coulombic efficiency of 99.58 %.

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Benefiting from the admirable energy density (1086 Wh kg-1 ), overwhelming security, and low environmental impact, rechargeable zinc-air batteries (ZABs) are deemed to be attractive candidates for lithium-ion batteries. The exploration of novel oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) bifunctional catalysts is the key to promoting the development of zinc-air batteries. Transitional metal phosphides (TMPs) especially Fe-based TMPs are deemed to be a rational type of catalyst, however, their catalytic performance still needs to be further improved. Considering Fe (heme) and Cu (copper terminal oxidases) are nature's options for ORR catalysis in many forms of life from bacteria to humans. Herein, a general "in situ etch-adsorption-phosphatization" strategy is designed for the fabrication of hollow FeP/Fe2 P/Cu3 P-N, P codoped carbon (FeP/Cu3 P-NPC) catalyst as the cathode of liquid and flexible ZABs. The liquid ZABs manifest a high peak power density of 158.5 mW cm-2 and outstanding long-term cycling performance (≈1100 cycles at 2 mA cm-2 ). Similarly, the flexible ZABs deliver superior cycling stability of 81 h at 2 mA cm-2 without bending and 26 h with different bending angles.

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Developing a conductive catalyst with high catalytic activity is considered to be an effective strategy for improving cathode kinetics of lithium-sulfur batteries, especially at large current density and with lean electrolytes. Lattice-strain engineering has been a strategy to tune the local structure of catalysts and to help understand the structure-activity relationship between strain and catalyst performance. Here, Co0.9 Zn0.1 Te2 @NC is constructed after zinc atoms are uniformly doped into the CoTe2 lattice. The experimental/theoretical results indicate that a change of the coordination environment for the cobalt atom by the lattice strain modulates the d-band center with more electrons occupied in antibonding orbitals, thus balancing the adsorption of polysulfides and the intrinsic catalytic effect, thereby activating the intrinsic activity of the catalyst. Benefiting from the merits, with only 4 wt% dosages of catalyst in the cathode, an initial discharge capacity of 1030 mAh g-1 can be achieved at 1 C and stable cycling performances are achieved for 1500/2500 cycles at 1 C/2 C. Upon sulfur loading of 7.7 mg cm-2 , the areal capacity can reach 12.8 mAh cm-2 . This work provides a guiding methodology for the design of catalytic materials and refinement of adsorption-catalysis strategies for the rational design of cathode in lithium-sulfur batteries.

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BACKGROUND: Intraventricular hemorrhage is a neurosurgical emergency, and a dangerous condition associated with high morbidity and mortality. Previously, hematoma evacuation is generally executed by external intracranial drainage (EVD) or surgical evacuation. Nowadays, endoscopic evacuation is emerging as a good alternative because it brings relatively less invasion and injury. However, successful endoscopic evacuation requires skilled manipulation of endoscopic devices and the evidence supporting its efficacy differs in different reports. AIM: To improve the technique usage and provide more evidence of endoscopic evacuation efficacy, we summarize our surgical experience and compared the outcomes of the endoscopic evacuation with EVD using real-world data. METHODS: We retrospectively studied 96 consecutive patients with intraventricular hemorrhage who underwent either endoscopic surgery (n = 43) or non-endoscopic surgery (n = 53) for hemorrhage evacuation between November 2013 and September 2019 in our center. Patients' conditions prior to and after the operation were evaluated and analyzed to assess the efficacy of the operation. The consciousness status improvement and perioperative in-hospital parameters in the two types of operation groups were assessed and compared. RESULTS: Patients in the endoscopic and non-endoscopic groups presented with a similar state of consciousness, with a comparable Glasgow Coma Scale (GCS) index. The average operation time of the endoscopic group was longer than that of the non-endoscopic group (median 2.42 h vs 1.08 h, P < 0.001). Although the endoscopic group was older and had a baseline Graeb score that indicated more severe hemorrhage than the non-endoscopic group (Graeb median: Endoscopic group = 9 vs non-endoscopic group = 8, P = 0.023), the clearance rate of hematoma was as high as 60.5%. Both the endoscopic and non-endoscopic groups showed an improved GCS index after surgery. However, this improvement was more marked in patients in the endoscopic group (median improvement of GCS index: Endoscope group = 4 vs non-endoscopic group = 1, P < 0.001). Additionally, the endoscopic group had a lower Graeb score than the non-endoscopic group after the operation. The intensive care unit stay of the endoscopic group was significantly shorter than that of the non-endoscopic group (median: endoscopic group = 6 d vs non-endoscope group = 7 d, P = 0.017). CONCLUSION: Endoscopic evacuation of intraventricular hemorrhage was generally an effective and efficient way for hemorrhage evacuation, and contributed remarkably to the improvement of consciousness in patients with intraventricular hemorrhage.

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Circular RNA takes a crucial part in carcinogenesis. Circ_0058063 has been found to act as an oncogene in esophageal cancer and bladder cancer, but its role in thyroid cancer (TC) is still under investigation. Therefore, we carried out a study to understand its role in TC and its association with miR-330-3p. The circ_0058063 and miR-330-3p in TC tissues and cells were quantified by quantitative reverse transcription PCR, and cell counting kit-8 and scratch adhesion test were conducted for evaluation of cell proliferation and migration. In addition, a dual luciferase reporter assay and RNA immunoprecipitation assay were conducted for interaction analysis between circ_0058063 and miR-330-3p. Circ_0058063 was upregulated in TC tissues and cells, but miR-330-3p expression showed an opposite trend. Both silencing circ_0058063 and upregulating miR-330-3p can suppress the proliferation and migration of TC cells, upregulate Bax, and downregulate Bcl-2. In addition, circ_0058063 is able to target miR-330-3p that is also able to target syndecan 4 (SDC4). circ_0058063 can act as a carcinogen in cases with TC via the miR-330-3p/SDC4 axis.

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Metal sulfides are promising anodes for potassium-ion batteries (PIBs) due to their high theoretical capacity and abundant active sites; however, their intrinsic low conductivity and poor cycling stability hampered their practical applications. Given this, the rational design of hybrid structures with high stability and fast charge transfer is a critical approach. Herein, CoS2/ZnS@rGO hybrid nanocomposites were demonstrated with stable cubic phases. The synergistic effect of the obtained bimetallic sulfide nanoparticles and highly conductive 2D rGO nanosheets facilitated excellent long-term cyclability for potassium ion storage. Such hybrid nanocomposites delivered remarkable ultrastable cycling performances in PIBs of 159, 106, and 80 mA h g-1 at 1, 1.5, and 2 A g-1 after 1800, 2100, and 3000 cycles, respectively. Moreover, the full-cell configuration with a perylene tetracarboxylic dianhydride organic cathode (CoS2/ZnS@rGO∥PTCDA) exhibited a better electrochemical performance. Besides, when the CoS2/ZnS@rGO nanocomposites were applied as an anode for sodium-ion batteries, the electrode demonstrated a reversible charge capacity of 259 mA h g-1 after 600 cycles at 2 A g-1. In situ X-ray diffraction and ex situ high-resolution transmission electron microscopy characterizations further confirmed the conversion reactions of CoS2/ZnS during insertion/desertion processes. Our synthesis strategy is also a general route to other bimetallic sulfide hybrid nanocomposites. This strategy opens up a new roadmap for exploring hybrid nanocomposites with feasible phase engineering for achieving excellent electrochemical performances in energy storage applications.

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Suitable anode materials with high capacity and long cycling stability, especially capability at high current densities, are urgently needed to advance the development of potassium ion batteries (PIBs) and sodium ion batteries (SIBs). Herein, a porous Ni-doped FeSe2 /Fe3 Se4 heterojunction encapsulated in Se-doped carbon (NF11 S/C) is designed through selenization of MOFs precursor. The porous composite possesses enriched active sites and facilitates transport for both ion and electron. Ni-doping is adopted to enrich the lattice defects and active sites. The Se-C bond and carbon framework endow integrity of the composite and hamper aggregation of selenide nano-particles during potassiation/de-potassiation. The NF11 S/C exhibits exceptional rate performance and ultra-long cycling stability (177.3 mA h g-1 after 3050 cycles at 2 A g-1 for PIBs and 208.8 mA h g-1 after 2000 cycles at 8 A g-1 for SIBs). The potassiation/de-potassiation mechanism is investigated via ex-situ X-ray powder diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectrocopy and Raman analysis. PTCDA//NF11 S/C full cell stably cycles for 1200 cycles at 200 mA g-1 with a capacity of 103.7 mA h g-1 , indicating the high application potential of the electrode for highly stable rechargeable batteries.

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Exosomes are a heterogeneous group of nano-sized natural membrane vesicles released from various cells and exist in body fluids. Different from the previous understanding of the function of exosomes as "garbage bins", exosomes act as carriers with many kinds of bioactive molecules (e.g., proteins, lipids, and nucleic acids) to play an important role in cell-cell communication. Growing evidence in recent years has suggested that exosomes also play some roles in the pathogenesis, diagnosis, and treatment modalities of some brain diseases, including ischemic stroke, Alzheimer's disease, Parkinson's disease, multiple sclerosis, and brain cancers. Exosomes as therapeutic drug carriers for brain drug delivery have received extensive attention as well as exosomes can overcome the blood-brain barrier (BBB). However, the low targeting ability and size-dependent cellular uptake of native exosomes could profoundly affect the delivery performance of exosomes. Recent studies have indicated that engineered exosomes can increase the drug uptake efficiency and the subsequent drug efficacy. In the present paper, we will briefly introduce the engineering methods and applications of engineered exosomes in the treatment of brain diseases, and then focus on discussing the advantages and challenges of exosome- based drug delivery platforms to further enrich and boost the development of exosomes as a promising drug delivery strategy for brain diseases.

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Domoic acid (DA) is a major marine neurotoxin, occurs frequently in most of the world's coastlines and seriously threatens ecosystem and public health. However, information on its biotransformation process in coastal anaerobic environments remains unclear. In this study, the underlying mechanism of anaerobic biotransformation of DA by marine consortium GLY was investigated using the combination of liquid chromatography-high-resolution Orbitrap mass spectrometry and comparative metatranscriptomics analysis. The results demonstrated that DA could be cometabolically biotransformed under anaerobic conditions with pseudo-first-order reaction. Anaerobic biotransformation pathway of DA was clarified, including decarboxylation, dehydrogenation, carboxylation activation with CoA and multiple ß-oxidation steps occurring at aliphatic side chain, which facilitated DA detoxification. Furthermore, anaerobic cometabolic biotransformation mechanism of glycine-DA by consortium GLY was established for the first time, a number of genes related to the metabolic pathways of glycine fermentation, fatty acid synthesis and ß-oxidation were responded in the consortium GLY transcriptome and involved in the anaerobic biotransformation of DA. This study could deepen understanding of interaction mechanism between toxin DA and marine microorganisms, which provides a new insight into the DA fate and its effects on benthic microbial community in marine environments.

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Naphthenic acids (NAs) are a persistent toxic organic pollutant that occur in different environment worldwide and cause serious threat to the ecosystem and public health. However, knowledge on the behavior and fate of NAs in marine environments still remains unknown. In this study, the degradation mechanism of NAs (cyclohexylacetic acid, CHAA) was investigated using an common indigenous marine Pseudoalteromonas sp. The results showed that CHAA could be degraded completely under aerobic condition, but could not be utilized directly under anaerobic condition. Interestingly, transcriptome and key enzyme activity results showed the CHAA degradation pathway induced under aerobic condition could still work in anaerobic condition. The degradation was activated by acetyl-CoA transferase and sequentially formed the corresponding cyclohexene, alcohol, and ketone with the assistance of related enzymes, and finally cleaved by hydroxymethylglutarate-CoA lyase. Besides, there was a positive correlation between chemotaxis and aerobic degradation genes (r = 0.976, P < 0.05), the chemotaxis would enhance bacterium movement and NAs biodegradation. It is proposed that bacterium could translocate to NAs and accomplish biodegradation from aerobic to anaerobic environments, which was a new anaerobic degradation pathway of NAs. This study provides new insights into the fate of NAs and other organic contaminants in marine environment.

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Polyacrylate containing wastewater (PCW) is the typical sewage discharged by the textile industry. It has extremely poor biodegradability, and chemical methods were used conventionally as the only way for treating PCW. This study is demonstrating a novel biological method. In batch experiment monod kinetics was applied to the experimental data, which indicated that anaerobic treatment used for PCW is feasible. The pilot-scale experiment combined a Spiral Symmetry Stream Anaerobic Bioreactor (SSSAB) and an air-lift external circulation vortex enhancement nitrogen removal fluidized bed bioreactor (AFB). The COD and NH4+-N removal reached up to 95.2% and 96.6%, respectively, which were higher than the value obtained by other chemical methods. High-throughput sequencing analysis indicated that the relative abundance of Proteobacteria, Firmicutes and Bacteroidetes increased, which contribute to the degradation of PCW. Therefore, PCW can be degraded efficiently by using a SSSAB-AFB technique and thus provides an alternative to the chemical methods.

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