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Chronic pancreatitis (CP) is marked by progressive fibrosis and the activation of pancreatic stellate cells (PSCs), accompanied by the destruction of pancreatic parenchyma, leading to the loss of acinar cells (ACs). Few research studies have explored the mechanism by which damaged ACs (DACs) contribute to PSCs activation and pancreatic fibrosis. Currently, there are no effective drugs for curing CP or limiting the progression of pancreatic fibrosis. In this research, co-culture with intact acinar cells (IACs) suppressed PSC activation, while co-culture with DACs did the opposite. Krüppel-like factor 4 (KLF4) was significantly upregulated in DACs and was established as the key molecule that switches ACs from PSCs-suppressor to PSCs-activator. We revealed the exosomes of IACs contributed to the anti-activated function of IACs-CS on PSCs. MiRNome profiling showed that let-7 family is significantly enriched in IAC-derived exosomes (>30% miRNome), which partially mediates IACs' suppressive impacts on PSCs. Furthermore, it has been observed that the enrichment of let-7 in exosomes was influenced by the expression level of KLF4. Mechanistic studies demonstrated that KLF4 in ACs upregulated Lin28A, thereby decreasing let-7 levels in AC-derived exosomes, and thus promoting PSCs activation. We utilized an adeno-associated virus specifically targeting KLF4 in ACs (shKLF4-pAAV) to suppress PSCs activation in CP, resulting in reduced pancreatic fibrosis. IAC-derived exosomes hold potential as potent weapons against PSCs activation via let-7s, while activated KLF4/Lin28A signaling in DACs diminished such functions. ShKLF4-pAAV holds promise as a novel therapeutic approach for CP.
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Células Acinares , Exossomos , Fibrose , Fator 4 Semelhante a Kruppel , MicroRNAs , Células Estreladas do Pâncreas , Pancreatite Crônica , Fator 4 Semelhante a Kruppel/metabolismo , Animais , Células Estreladas do Pâncreas/metabolismo , Células Estreladas do Pâncreas/patologia , Exossomos/metabolismo , Pancreatite Crônica/metabolismo , Pancreatite Crônica/genética , Pancreatite Crônica/patologia , MicroRNAs/genética , Células Acinares/metabolismo , Células Acinares/patologia , Dependovirus/genética , Camundongos , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Modelos Animais de Doenças , Vetores Genéticos/genética , Vetores Genéticos/administração & dosagem , Masculino , Técnicas de Cocultura , Pâncreas/metabolismo , Pâncreas/patologia , Terapia Genética/métodosRESUMO
Nanofluidic channels with tailored ion transport dynamics are usually used as channels for ion transport, to enable high-performance ion regulation behaviors. The rational construction of nanofluidics and the introduction of external fields are of vital significance to the advancement and development of these ion transport properties. Focusing on the recent advances of nanofluidics, in this review, various dimensional nanomaterials and their derived homogeneous/heterogeneous nanofluidics are first briefly introduced. Then we discuss the basic principles and properties of ion transport in nanofluidics. As the major part of this review, we focus on recent progress in ion transport in nanofluidics regulated by external physical fields (electric field, light, heat, pressure, etc.) and chemical fields (pH, concentration gradient, chemical reaction, etc.), and reveal the advantages and ion regulation mechanisms of each type. Moreover, the representative applications of these nanofluidic channels in sensing, ionic devices, energy conversion, and other areas are summarized. Finally, the major challenges that need to be addressed in this research field and the future perspective of nanofluidics development and practical applications are briefly illustrated.
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Biological ion channels exhibit switchable cation transport with ultrahigh selectivity for efficient energy conversion, such as Ca2+-activated TRPM4 channels tuned by cation-π interactions, but achieving an analogous highly selective function is challenging in artificial nanochannels. Here, we design a TRPM4-inspired cation-selective nanochannel (CN) assembled by two poly(ether sulfone)s, respectively, with sulfonate acid and indole moieties, which act as cation-selective activators to manage Na+/Cl- selectivity via ionic and cation-π interactions. The cation selectivity of CNs can be activated by Na+, and thereby the Na+ transference number significantly improves from 0.720 to 0.982 (Na+/Cl- selectivity ratio from 2.6 to 54.6) under a 50-fold salinity gradient, surpassing the K+ transference number (0.886) and Li+ transference number (0.900). The TRPM4-inspired nanochannel membrane enabled a maximum output power density of 5.7 W m-2 for salinity-gradient power harvesting. Moreover, a record energy conversion efficiency of up to 46.5% is provided, superior to most nanochannel membranes (below 30%). This work proposes a novel strategy to biomimetic nanochannels for highly selective cation transport and high-efficiency salinity-gradient energy conversion.
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OBJECTIVE: Current study aims to investigate whether serum exosomal microRNAs (miRNAs) could be potential biomarkers in predicting APs with POF at early phase. BACKGROUND: Novel biomarkers are sorely needed for early prediction of persistent organ failure (POF) in acute pancreatitis (AP) patients. METHODS: In the discovery stage, exosomal miRNAs were profiled in sera from APs with or without POF (5 vs. 5) using microarrays. POF-associated miRNA signatures then were assessed in training cohort (n=227) and further validated in three independent cohorts (n=516), including one nested case-control cohort. RESULTS: A total of 743 APs were recruited in this large-scale biomarker identification study with a nested case-control study. Data from the discovery cohort demonstrated that 90 exosomal miRNAs were significantly dysregulated in APs with POF compared with controls. One miRNA classifier (Cmi) comprising 3 miRNAs (miR-4265, 1208, 3127-5p) was identified in the training cohort, and was further evaluated in two validation cohorts for their predictive value for POF. AUCs for Cmi ranged from 0.88 to 0.90, which was statistically superior to AUCs of APACHE-II and BISAP, and outperformed BUN and creatinine in POF prediction across all cohorts (P<.05). Higher levels of Cmi indicated increased need for ICU admission, prolonged hospitalization, and elevated mortality rate, thus poor prognosis. In the nested case-control study, Cmi could help identify prediagnostic POF in post-ERCP pancreatitis cases within "golden hours" after ERCP with high efficacy. CONCLUSIONS: Serum exosomal Cmi may be an early predictor for POF in AP, even within "golden hours" after AP onset. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02602808).
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Biological photo-responsive ion channels play important roles in the important metabolic processes of living beings. To mimic the unique functions of biological prototypes, the transition metal dichalcogenides, owing to their excellent mechanical, electrical, and optical properties, are already used for artificial intelligent channel constructions. However, there remain challenges to building artificial bio-semiconductor nanochannels with finely tuned band gaps for accurately simulating or regulating ion transport. Here, two well-designed peptides are employed for the WS2 nanosheets functionalization with the sequences of PFPFPFPFC and DFDFDFDFC (PFC and DFC; P: proline, D: aspartate, and F: phenylalanine) through cysteine (Cys, C) linker, and an asymmetric peptide-WS2 membrane (AP-WS2M) could be obtained via self-assembly of peptide-WS2 nanosheets. The AP-WS2M could realize the photo-driven anti-gradient ion transport and vis-light enhanced osmotic energy conversion by well-designed working patterns. The photo-driven ion transport mechanism stems from a built-in photovoltaic motive force with the help of formed type II band alignment between the PFC-WS2 and DFC-WS2. As a result, the ions would be driven across the channels of the membrane for different applications. The proposed system provides an effective solution for building photo-driven biomimetic 2D bio-semiconductor ion channels, which could be extensively applied in the fields of drug delivery, desalination, and energy conversion.
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We report two-dimensional (2D) Ni/Co-based metal hydroxide-organic framework nanosheets (Ni/Co-MHOF NSs) for the construction of an efficient electrochemical nonenzymatic glucose sensor. The nanosheet architecture maximizes the exposure of coordinatively unsaturated metal sites, which enables a largely improved electrocatalytic performance toward the glucose oxidation reaction. The as-designed nonenzymatic sensor exhibits a high sensitivity of 235.71 µA·mM-1·cm-2 and a wide linear range of 1-3000 µM. The sensor presents excellent selectivity against several potential interferences and a short response time of 3.0 s. Of interest, a high-performance flexible sensor is developed by depositing the Ni/Co-MHOF NSs on screen-printed electrodes, which reveal decent bending stability. The designed glucose sensor patch can attach to the human body and realize noninvasive glucose monitoring in human sweat. This work may shed light on the application of novel MHOFs in the field of wearable electrochemical sensing.
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BACKGROUND: Occult pancreaticobiliary reflux (OPBR) has a significant correlation with diseases of the gallbladder and biliary system. This study examined the incidence of OPBR by age in patients with benign gallbladder diseases. METHODS: We assessed 475 patients with benign gallbladder diseases who underwent surgery at Shanghai East Hospital from December 2020 to December 2021. Bile samples collected during surgery were tested for amylase. Patients with bile amylase >110 U/L (n = 64) were classified as the OPBR group; the rest (n = 411) as controls. RESULTS: Of the participants, 375 had gallbladder stone (GS), 170 had gallbladder polyp (GP), and 49 had gallbladder adenomyomatosis (GA). The OPBR group was generally older, with OPBR incidence increasing with age, peaking post-45. Rates by age were: 4.9% (<35), 5.2% (35-44), 20.7% (45-54), 22.5% (55-64) and 17.6% (≥65), mainly in GS patients. ROC analysis for predicting OPBR by age yielded an area under the curve of 0.656, optimal cut-off at 45 years. Logistic regression indicated age > 45, GP, male gender, and BMI ≥ 24 kg*m-2 as independent OPBR predictors in GS patients. Based on these variables, a predictive nomogram was constructed, and its effectiveness was validated using the ROC curve, calibration curve and decision curve analysis (DCA). Further stratification revealed that among GS patients ≤ 45, concurrent GA was an OPBR risk; for > 45, it was GP and male gender. CONCLUSIONS: The incidence of OPBR in GS patients is notably influenced by age, with those over 45, especially males without GP, being at heightened risk.
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Refluxo Biliar , Doenças da Vesícula Biliar , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Incidência , Idoso , China/epidemiologia , Doenças da Vesícula Biliar/epidemiologia , Doenças da Vesícula Biliar/complicações , Doenças da Vesícula Biliar/cirurgia , Fatores Etários , Refluxo Biliar/complicações , Refluxo Biliar/epidemiologia , Modelos Logísticos , Curva ROC , Cálculos Biliares/complicações , Cálculos Biliares/epidemiologia , Cálculos Biliares/cirurgia , Fatores de Risco , Bile , Neoplasias da Vesícula Biliar/epidemiologia , Pólipos/epidemiologia , Pólipos/complicações , Amilases/análiseRESUMO
In pancreatic ductal adenocarcinomas (PDAC), profound hypoxia plays key roles in regulating cancer cell behavior, including proliferation, migration, and resistance to therapies. The initial part of this research highlights the important role played by long noncoding RNA (lncRNA) MKLN1-AS, which is controlled by hypoxia-inducible factor-1 alpha (HIF-1α), in the progression of PDAC. Human samples of PDAC showed a notable increase in MKLN1-AS expression, which was linked to a worse outcome. Forced expression of MKLN1-AS greatly reduced the inhibitory impact on the growth and spread of PDAC cells caused by HIF-1α depletion. Experiments on mechanisms showed that HIF-1α influences the expression of MKLN1-AS by directly attaching to a hypoxia response element in the promoter region of MKLN1-AS.MKLN1-AS acts as a competitive endogenous RNA (ceRNA) by binding to miR-185-5p, resulting in the regulation of TEAD1 expression and promoting cell proliferation, migration, and tumor growth. TEAD1 subsequently enhances the development of PDAC. Our study results suggest that MKLN1-AS could serve as a promising target for treatment and a valuable indicator for predicting outcomes in PDAC. PDAC is associated with low oxygen levels, and the long non-coding RNA MKLN1-AS interacts with TEAD1 in this context.
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Carcinoma Ductal Pancreático , Movimento Celular , Proliferação de Células , Proteínas de Ligação a DNA , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia , MicroRNAs , Neoplasias Pancreáticas , RNA Longo não Codificante , Fatores de Transcrição de Domínio TEA , Animais , Humanos , Camundongos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição de Domínio TEA/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
INTRODUCTION: Pancreaticobiliary reflux (PBR) can induce gallstone formation; however, its pathogenic mechanism remains unclear. In this study, we explored the mechanism of PBR by the non-targeted metabolomic analysis of bile in patients with PBR. OBJECTIVE: The aim of this study was to investigate the pathogenic mechanism in PBR by the non-targeted metabolomic analysis of bile collected during surgery. METHODS: Sixty patients who underwent gallstone surgery at our center from December 2020 to May 2021 were enrolled in the study. According to the level of bile amylase, 30 patients with increased bile amylase ( > 110 U/L) were classified into the PBR group, and the remaining 30 patients were classified into the control group (≤ 110 U/L). The metabolomic analysis of bile was performed. RESULTS: The orthogonal projections to latent structure-discriminant analysis of liquid chromatography mass spectrometry showed significant differences in bile components between the PBR and control groups, and 40 metabolites were screened by variable importance for the projection value (VIP > 1). The levels of phosphatidylcholine (PC) and PC (20:3(8Z,11Z,14Z)/14:0) decreased significantly, whereas the levels of lysoPC (16:1(9z)/0:0), lysoPC (15:0), lysoPC (16:0), palmitic acid, arachidonic acid, leucine, methionine, L-tyrosine, and phenylalanine increased. CONCLUSIONS: Significant differences in bile metabolites were observed between the PBR and control groups. Changes in amino acids and lipid metabolites may be related to stone formation and mucosal inflammation.
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Bile , Cálculos Biliares , Humanos , Cálculos Biliares/cirurgia , Cálculos Biliares/metabolismo , Metabolômica/métodos , Espectrometria de Massa com Cromatografia Líquida , AmilasesRESUMO
Motivated by the clinical success of combining tyrosine kinase inhibitors with microtubule-targeted drugs in antitumor treatment, this paper presents a novel combi-targeting design for dual-target inhibitors, featuring arylformylurea-coupled quinazoline backbones. A series of target compounds (10a-10r) were designed, synthesized, and characterized. Biological assessments demonstrated that 10c notably potentiated ten tumor cell lines in vitro, with IC50 values ranging from 1.04 µM to 7.66 µM. Importantly, 10c (IC50 = 10.66 nM) exhibited superior inhibitory activity against EGFR kinases compared to the reference drug Gefitinib (25.42 nM) and reduced phosphorylated levels of EGFR, AKT, and ERK. Moreover, 10c significantly impeded tubulin polymerization, disrupted the intracellular microtubule network in A549 cells, induced apoptosis, led to S-phase cell cycle arrest, and hindered cell migration. In anticancer evaluation tests using A549 cancer-bearing nude mice models, 10c showed a therapeutic effect similar to Gefitinib, but required only half the dosage (15 mg/kg). These findings indicate that compound 10c is a promising dual-target candidate for anticancer therapy.
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Antineoplásicos , Moduladores de Tubulina , Animais , Camundongos , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB , Gefitinibe/farmacologia , Camundongos Nus , Microtúbulos/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Relação Estrutura-Atividade , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , /farmacologiaRESUMO
Platinum-based drugs are widely used in chemotherapy for various types of cancer and are considered crucial. Tetravalent platinum (Pt(IV)) compounds have gained significant attention and have been extensively researched among these drugs. Traditionally, Pt(IV) compounds are reduced to divalent platinum (Pt(II)) after entering cells, causing DNA lesions and exhibiting their anti-tumor effect. However, the available evidence indicates that some Pt(IV) derivatives may differ from the traditional mechanism and exert their anti-tumor effect through their overall structure. This review primarily focuses on the existing literature regarding targeted Pt(II) and Pt(IV) compounds, with a specific emphasis on their in vivo mode of action and the properties of reduction release in multifunctional Pt(IV) compounds. This review provides a comprehensive summary of the design and synthesis strategies employed for Pt(II) derivatives that selectively target various enzymes (glucose receptor, folate, telomerase, etc.) or substances (mitochondria, oleic acid, etc.). Furthermore, it thoroughly examines and summarizes the rational design, anti-tumor mechanism of action, and reductive release capacity of novel multifunctional Pt(IV) compounds, such as those targeting p53-MDM2, COX-2, lipid metabolism, dual drugs, and drug delivery systems. Finally, this review aims to provide theoretical support for the rational design and development of new targeted Pt(IV) compounds.
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Antineoplásicos , Neoplasias , Pró-Fármacos , Humanos , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Platina/química , Neoplasias/tratamento farmacológico , Linhagem Celular TumoralRESUMO
Numerous reported bioinspired osmotic energy conversion systems employing cation-/anion-selective membranes and solutions with different salinity are actually far from the biological counterpart. The iso-osmotic power generator with the specific ionic permselective channels (e.g., K+ or Na+ channels) which just allow specific ions to get across and iso-osmotic solutions still remain challenges. Inspired by nature, we report a bioinspired K+ -channel by employing a K+ selective ligand, 1,1,1-tris{[(2'-benzylaminoformyl)phenoxy]methyl}ethane (BMP) and graphene oxide membrane. Specifically, the K+ and Na+ selectivity of the prepared system could reach up to ≈17.8, and the molecular dynamics simulation revealed that the excellent permselectivity of K+ mainly stemmed from the formed suitable channel size. Thus, we assembled the K+ -selective iso-osmotic power generator (KSIPG) with the power density up to ≈15.1â mW/m2 between equal concentration solutions, which is higher than traditional charge-selective osmotic power generator (CSOPG). The proposed strategy has well shown the realizable approach to construct single-ion selective channels-based highly efficient iso-osmotic energy conversion systems and would surely inspire new applications in other fields, including self-powered systems and medical materials, etc.
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Goal: Deep learning techniques have made significant progress in medical image analysis. However, obtaining ground truth labels for unlabeled medical images is challenging as they often outnumber labeled images. Thus, training a high-performance model with limited labeled data has become a crucial challenge. Methods: This study introduces an underlying knowledge-based semi-supervised framework called UKSSL, consisting of two components: MedCLR extracts feature representations from the unlabeled dataset; UKMLP utilizes the representation and fine-tunes it with the limited labeled dataset to classify the medical images. Results: UKSSL evaluates on the LC25000 and BCCD datasets, using only 50% labeled data. It gets precision, recall, F1-score, and accuracy of 98.9% on LC25000 and 94.3%, 94.5%, 94.3%, and 94.1% on BCCD, respectively. These results outperform other supervised-learning methods using 100% labeled data. Conclusions: The UKSSL can efficiently extract underlying knowledge from the unlabeled dataset and perform better using limited labeled medical images.
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This present work investigated the influence of black rice anthocyanins as antioxidants on the oxidation stability of oil. Malonic acid, succinic acid and succinic anhydride were grafted on black rice anthocyanins through acylation method to improve their antioxidant activity in oil. The results from fourier transform infrared spectroscopy (FTIR) showed new absorption peaks near 1744 cm -1 and 1514 cm -1 , which implied that malonic acid, succinic acid and succinic anhydride grafted on the -OH of glucoside and rutinoside through esterification reaction and resulted that the polarity of these were reduced. Total content of anthocyanin (TAC) decreased to 166. 3 mg/g, 163.7 mg/g and 150.2 mg/g, respectively after modification with succinic acid, malonic acid and succinic anhydride. Compared with native anthocyanins, the acylation of black rice anthocyanins partially reduced its antioxidant activity. In addition, DPPH clearance of molecular modified anthocyanins decreased to 62.6% (San-An). As revealed in the oil stability through the determination of primary oxidation products (PV) and secondary oxidation products (p-AV), Sa-An, Ma-An and San-An showed stronger antioxidant activity in Schaal oven accelerated oxidation test during 12 days than native black rice anthocyanin in both corn oil and flaxseed oil. Molecular modified black rice anthocyanins are expected to be used as colorants, antioxidants, etc. in oil-rich food.
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Antocianinas , Antioxidantes , Oryza , Oxirredução , Antocianinas/química , Antocianinas/farmacologia , Antioxidantes/farmacologia , Oryza/química , Acilação , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Outer membrane vesicles (OMVs) are nanoscale lipid bilayer structures released by gram-negative bacteria. They share membrane composition and properties with their originating cells, making them adept at traversing cellular barriers. These OMVs have demonstrated exceptional membrane stability, immunogenicity, safety, penetration, and tumor-targeting properties, which have been leveraged in developing vaccines and drug delivery systems. Recent research efforts have focused on engineering OMVs to increase production yield, reduce cytotoxicity, and improve the safety and efficacy of treatment. Notably, gastrointestinal (GI) tumors have proven resistant to several traditional oncological treatment strategies, including chemotherapy, radiotherapy, and targeted therapy. Although immune checkpoint inhibitors have demonstrated efficacy in some patients, their usage as monotherapy remains limited by tumor heterogeneity and individual variability. The immunogenic and modifiable nature of OMVs makes them an ideal design platform for the individualized treatment of GI tumors. OMV-based therapy enables combination therapy and optimization of anti-tumor effects. This review comprehensively summarizes recent advances in OMV engineering for GI tumor therapy and discusses the challenges in the clinical translation of emerging OMV-based anti-tumor therapies.
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Vesículas Extracelulares , Neoplasias Gastrointestinais , Vacinas , Humanos , Membrana Externa Bacteriana , Bactérias , Neoplasias Gastrointestinais/terapia , Proteínas da Membrana Bacteriana ExternaRESUMO
Background: Vascular cognitive impairment (VCI) is the second leading cause of dementia. Cognitive impairment is a common consequence of VCI. However, there is no effective treatment for VCI and the underlying mechanism of its pathogenesis remains unclear. This study to investigate whether artesunate (ART) can improve the learning and memory function in rats with VCI by down-regulating he level of autophagy in cerebral cortex neurons. Methods: The models for VCI were the rat bilateral common carotid artery occlusion (BACCO), which were randomized into three groups including the sham operation group (Sham), model + vehicle group (Model) and model + ART group (ART). Then the animal behaviors were recorded, as well as staining the results of cortical neurons. Western blot was performed to determine the protein expressions of LC3Bâ ¡/â , p-AMPK, p-mTOR, and Beclin-1. Results: Behavioral outcomes and the protein expressions in Model group were supposedly affected by the induction of autophagy in cerebral cortex neurons. Compared to the Model group, ART improved memory impairment in VCI rats. And the expression of LC3Bâ ¡/â , p-AMPK/AMPK, Beclin-1 is significant decreased in the ART group, while significant increases of p-mTOR/mTOR were showed. These results suggest that ART improved learning and memory impairment in VCI rats by down-regulating the level of autophagy in cerebral cortex neurons. Conclusion: The results suggest that autophagy occurs in cerebral cortex neurons in rats with VCI. It is speculated that ART can improve learning and memory impairment in VCI rats by down-regulating the level of autophagy in cerebral cortex neurons.
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The intrinsic issue associated with the application of microbes for practical pollution remediation involves maintaining the expected activity of engaged strains or consortiums as effectively as that noted under laboratory conditions. Faced with various stress factors, degraders with dormancy ability are more likely to survive and exhibit degradation activity. In this study, a hydrocarbonoclastic and halotolerant strain, Gordonia polyisoprenivorans ZM27, was isolated via stimulation with resuscitation-promoting factor (Rpf). Long-term exposure to dual stresses of 10% NaCl and starvation induced ZM27 to enter a viable but nonculturable (VBNC)-like state, and ZM27 cells could be resuscitated upon Rpf stimulation. Notable changes in both morphological and physiological characteristics between VBNC-like ZM27 cells and resuscitated cells confirmed the response to Rpf and their robust resistance against harsh environments. Whole-genome sequencing and analysis indicated ZM27 could be a generalist degrader with dormancy ability. Subsequently, VBNC-like ZM27 was applied in a soil microcosm experiment to investigate the practical application potential under harsh conditions. VBNC-like ZM27 combined with Rpf stimulation exhibited the most effective biodegradation performance, and the initial n-hexadecane content (1000 mg kg-1) decreased by 63.29% after 14-day incubation. Based on 16S rRNA amplicon sequencing and analysis, Gordonia exhibited a positive response to Rpf stimulation. The relative abundance of genus Gordonia was negatively correlated with that of Alcanivorax, a genus of obligate hydrocarbon degrader with the greatest abundance during soil incubation. Based on the degradation profile and community analysis, generalist Gordonia may be more efficient in hydrocarbon degradation than specialist Alcanivorax under harsh conditions. The characteristics of ZM27, including its sustainable culturability under long-term stress, response to Rpf and robust performance in soil microcosms, are valuable for the remediation of petroleum pollution under stressful conditions. Our work validated the importance of dormancy and highlighted the underestimated role of low-activity degraders in petroleum remediation.
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Currently, dairy mastitis caused by Staphylococcus xylosus poses a serious challenge for dairy farming. In this study, we explored the role and mechanism of rhein against S. xylosus with the hope of providing new research ideas to solve mastitis in dairy cows and ensure the source safety of dairy products. Through in vitro antimicrobial studies, we found that the minimum inhibitory concentration (MIC) of rhein was 64 µg/mL, and it significantly interfered with the formation of S. xylosus biofilm at sub-MIC. In experiments on mastitis in mice, rhein alleviated inflammation in mammary tissue, reduced the levels of TNF-α and IL-6, and decreased the number of S. xylosus. To explore the anti-S. xylosus mechanism of rhein, we identified the relevant proteins involved in carbon metabolism (Glycolysis/gluconeogenesis, TCA cycle, Fatty acid degradation) through proteomics. Additionally, proteins associated with the respiratory chain, oxidative stress (proteins of antioxidant and DNA repair), and nitrate respiration were also found to be upregulated. Thus, rhein may act as an antibacterial agent by interfering with the respiratory metabolism of S. xylosus and inducing the production of ROS, high levels of which alter the permeability of bacterial cell membranes and cause damage to them. We measured the concentrations of extracellular ß-galactosidase and nucleic acids. Additionally, SEM observation of S. xylosus morphology showed elevated membrane permeability and damage to the cell membrane. Finally, RT-PCR experiments showed that mRNAs of key proteins of the TCA cycle (odhA, mqo) and nitrate respiration (nreB, nreC, narG) were significantly up-regulated, consistent with proteomic results. In conclusion, rhein has good anti-S. xylosus effects in vitro and in vivo, by interfering with bacterial energy metabolism, inducing ROS production, and causing cell membrane and DNA damage, which may be one of the important mechanisms of its antimicrobial activity.
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With the rapid development of the lithium ion battery industry, emerging lithium (Li) enrichment in nature has attracted ever-growing attention due to the biotoxicity of high Li levels. To date, fast lithium ion (Li+) detection remains urgent but is limited by the selectivity, sensitivity, and stability of conventional technologies based on passive response processes. In nature, archaeal plasma membrane ion exchangers (NCLX_Mj) exhibit Li+-gated multi/monovalent ion transport behavior, activated by different stimuli. Inspired by NCLX_Mj, we design a pH-controlled biomimetic Li+-responsive solid-state nanochannel system for on-demand Li+ detection using 2-(2-hydroxyphenyl)benzoxazole (HPBO) units as Li+ recognition groups. Pristine HPBO is not reactive to Li+, whereas negatively charged HPBO enables specific Li+ coordination under alkaline conditions to decrease the ion exchange capacity of nanochannels. On-demand Li+ detection is achieved by monitoring the decline in currents, thereby ensuring precise and stable Li+ recognition (>0.1 mM) in the toxic range of Li+ concentration (>1.5 mM) for human beings. This work provides a new approach to constructing Li+ detection nanodevices and has potential for applications of Li-related industries and medical services.
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Nanofluidic membranes offer exceptional promise for osmotic energy conversion, but the challenge of balancing ionic selectivity and permeability persists. Here, we present a bionic nanofluidic system based on two-dimensional (2D) copper tetra-(4-carboxyphenyl) porphyrin framework (Cu-TCPP). The inherent nanoporous structure and horizontal interlayer channels endow the Cu-TCPP membrane with ultrahigh ion permeability and allow for a power density of 16.64 W m-2, surpassing state of-the-art nanochannel membranes. Moreover, leveraging the photo-thermal property of Cu-TCPP, light-controlled ion active transport is realized even under natural sunlight. By combining solar energy with salinity gradient, the driving force for ion transport is reinforced, leading to further improvements in energy conversion performance. Notably, light could even eliminate the need for salinity gradient, achieving a power density of 0.82 W m-2 in a symmetric solution system. Our work introduces a new perspective on developing advanced membranes for solar/ionic energy conversion and extends the concept of salinity energy to a notion of ionic energy.