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Background: Body composition is recognized to be associated with clinical outcomes in patients with locally advanced rectal cancer (LARC). This study aimed to determine the prognostic role of regional adipose tissue distribution in patients with resectable LARC treated with or without neoadjuvant chemoradiotherapy (nCRT). Methods: This retrospective study included 281 consecutive patients who underwent radical surgery for LARC with or without preoperative nCRT between 2013 and 2019. Patients underwent contrast-enhanced CT scans before nCRT and before surgery. Visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (aSAT), and gluteal subcutaneous adipose tissue (gSAT) were quantified on the CT images. The association of adipose tissue distribution with progression-free survival (PFS) was analyzed using Cox proportional hazards analysis. Results: A total of 102 nCRT-treated and 179 primarily resected patients were included. During a median follow-up period of 24 months, 74 (26.3%) patients experienced local recurrence or metastasis. Multivariable analysis showed that VAT was associated with PFS in all patients (hazard ratio [HR] 1.28, 95% confidence interval [CI] 1.04-1.57; P = 0.021). This association was only maintained in primarily resected patients (HR 1.31, 95% CI 1.02-1.69; P = 0.037). For patients receiving preoperative nCRT, VAT was not significantly associated with PFS, while the dynamic change in gSAT (ΔgSAT) between nCRT and surgery was associated with PFS (HR 0.43, 95%CI 0.27-0.69, P = 0.001). Conclusion: Visceral obesity is an adverse prognostic factor in patients with resectable LARC treated by primary resection, while increased gluteal subcutaneous adiposity during preoperative nCRT may indicate favorable clinical outcomes.
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The basal plane of transition metal dichalcogenides (TMDCs) is inert for the hydrogen evolution reaction (HER) due to its low-efficiency charge transfer kinetics. We propose a strategy of filling the van der Waals (vdW) layer with delocalized electrons to enable vertical penetration of electrons from the collector to the adsorption intermediate vertically. Guided by density functional theory, we achieve this concept by incorporating Cu atoms into the interlayers of tantalum disulfide (TaS2). The delocalized electrons of d-orbitals of the interlayered Cu can constitute the charge transfer pathways in the vertical direction, thus overcoming the hopping migration through vdW gaps. The vertical conductivity of TaS2 increased by 2 orders of magnitude. The TaS2 basal plane HER activity was extracted with an on-chip microcell. Modified by the delocalized electrons, the current density increased by 20 times, reaching an ultrahigh value of 800 mA cm-2 at -0.4 V without iR compensation.
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Autophagy is a process that eliminates damaged cells and malfunctioning organelles via lysosomes, which is closely linked to cancer. Primaquine (PQ) was reported to impede autophagy flow by preventing autophagosomes from fusing with lysosomes at the late stage of autophagy. It will lead to cellular metabolic collapse and programmed cell death. Excessive or extended autophagy enhances the efficacy of chemotherapeutic drugs in cancer prevention. The utilization of autophagy inhibition in conjunction with chemotherapy has become a prevalent and reliable approach for the safe and efficient treatment of cancer. In this work, an acid-sensitive nanoprodrug (O@PD) targeting CD44 receptors was produced using Schiff-base linkages or electrostatic interactions from oxidized hyaluronic acid (OHA), PQ, and doxorubicin (DOX). The CD44-targeting prodrug system in triple-negative breast cancer (TNBC) cells was designed to selectively release DOX and PQ into the acidic tumor microenvironment and cellular endosomes. DOX was employed to investigate the cellular uptake and ex-vivo drug distribution of O@PD nanoprodrugs. PQ-induced autophagy suppression combined with DOX has a synergistic fatal impact in TNBC. O@PD nanoprodrugs demonstrated robust anticancer efficacy as well as excellent biological safety, making them suitable for clinical use.
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Autofagia , Doxorrubicina , Ácido Hialurônico , Pró-Fármacos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Autofagia/efeitos dos fármacos , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Animais , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/química , Nanopartículas/química , Camundongos , Feminino , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Receptores de Hialuronatos/metabolismo , Sinergismo FarmacológicoRESUMO
Background: Melioidosis pneumonia, caused by the bacterium Burkholderia pseudomallei, is a serious infectious disease prevalent in tropical regions. Chest computed tomography (CT) has emerged as a valuable tool for assessing the severity and progression of lung involvement in melioidosis pneumonia. However, there persists a need for the quantitative assessment of CT characteristics and staging methodologies to precisely anticipate disease progression. This study aimed to quantitatively extract CT features and evaluate a CT score-based staging system in predicting the progression of melioidosis pneumonia. Methods: This study included 97 patients with culture-confirmed melioidosis pneumonia who presented between January 2002 and December 2021. Lung segmentation and annotation of lesions (consolidation, nodules, and cavity) were used for feature extraction. The features, including the involved area, amount, and intensity, were extracted. The CT scores of the lesion features were defined by the feature importance weight and qualitative stage of melioidosis pneumonia. Gaussian process regression (GPR) was used to predict patients with severe or critical melioidosis pneumonia according to CT scores. Results: The melioidosis pneumonia stages included acute stage (0-7 days), subacute stage (8-28 days), and chronic stage (>28 days). In the acute stage, the CT scores of all patients ranged from 2.5 to 6.5. In the subacute stage, the CT scores for the severe and mild patients were 3.0-7.0 and 2.0-5.0, respectively. In the chronic stage, the CT score of the mild patients fluctuated approximately between 2.5 and 3.5 in a linear distribution. Consolidation was the most common type of lung lesion in those with melioidosis pneumonia. Between stages I and II, the percentage of severe scans with nodules dropped from 72.22% to 47.62% (P<0.05), and the percentage of severe scans with cavities significantly increased from 16.67% to 57.14% (P<0.05). The GPR optimization function yielded area under the receiver operating characteristic curves of 0.71 for stage I, 0.92 for stage II, and 0.87 for all stages. Conclusions: In patients with melioidosis pneumonia, it is reasonable to divide the period (the whole progression of melioidosis pneumonia) into three stages to determine the prognosis.
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Silicon (Si) has gained substantial interest as a potential component of lithium-ion battery (LIB) anodes due to its high theoretical specific capacity. However, conventional methods for producing Si for anodes involve expensive metal reductants and stringent reducing environments. This paper describes the development of a calcium hydride (CaH2)-aluminum chloride (AlCl3) reduction system that was used for the in-situ low-temperature synthesis of a core-shell structured silicon-carbon (Si-C) material from rice husks (RHs), and the material was denoted RHs-Si@C. Moreover, as an LIB anode, RHs-Si@C exhibited exceptional cycling performance, exemplified by 90.63 % capacity retention at 5 A g-1 over 2000 cycles. Furthermore, the CaH2-AlCl3 reduction system was employed to produce Si nanoparticles (Si NPs) from RHs (R-SiO2, where SiO2 is silica) and from commercial silica (C-SiO2). The R-SiO2-derived Si NPs exhibited a higher residual silicon oxides (SiOx) content than the C-SiO2-derived Si NPs. This was advantageous, as there was sufficient SiOx in the R-SiO2-derived Si NPs to mitigate the volumetric expansion typically associated with Si NPs, resulting in enhanced cycling performance. Impressively, Si NPs were fabricated on a kilogram scale from C-SiO2 in a yield of 82 %, underscoring the scalability of the low-temperature reduction technique.
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Cancer cells rely on aerobic glycolysis and DNA repair signals to drive tumor growth and develop drug resistance. Yet, fine-tuning aerobic glycolysis with the assist of nanotechnology, for example, dampening lactate dehydrogenase (LDH) for cancer cell metabolic reprograming remains to be investigated. Here we focus on anaplastic thyroid cancer (ATC) as an extremely malignant cancer with the high expression of LDH, and develop a pH-responsive and nucleus-targeting platinum nanocluster (Pt@TAT/sPEG) to simultaneously targets LDH and exacerbates DNA damage. Pt@TAT/sPEG effectively disrupts LDH activity, reducing lactate production and ATP levels, and meanwhile induces ROS production, DNA damage, and apoptosis in ATC tumor cells. We found Pt@TAT/sPEG also blocks nucleotide excision repair pathway and achieves effective tumor cell killing. In an orthotopic ATC xenograft model, Pt@TAT/sPEG demonstrates superior tumor growth suppression compared to Pt@sPEG and cisplatin. This nanostrategy offers a feasible approach to simultaneously inhibit glycolysis and DNA repair for metabolic reprogramming and enhanced tumor chemotherapy.
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Antineoplásicos , Reparo do DNA , Glicólise , Camundongos Nus , Platina , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Glicólise/efeitos dos fármacos , Animais , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/patologia , Carcinoma Anaplásico da Tireoide/metabolismo , Reparo do DNA/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Platina/química , Platina/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Núcleo Celular/metabolismo , Núcleo Celular/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Camundongos Endogâmicos BALB C , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
OBJECTIVE: To study the distribution characteristics of CYP2C19 polymorphisms in patients suffering from stroke in Han Chinese patients. METHOD: PCR and DNA microarray chip technology were used to detect the CYP2C19 genotype of 549 patients with stroke, and the genotype, allele frequency and metabolic type of patients with different sexes, ages and types of infarctions and the independent risk factors for clopidogrel resistance were analyzed. RESULTS: Six genotypes were detected in these 549 patients. A total of 233 (42.44%) patients had the heterozygous allele *1/*2, which was the most prevalent, followed by the homozygous wild-type allele *1/*1 (191, 34.79%). A total of 30 (5.46%) patients possessed the heterozygous allele *1/*3, and 65 (11.84%) patients had the homozygous mutant allele *2/*2. Twenty-nine (5.28%) patients had the compound heterozygous mutant allele *2/*3, and only 1 patient had the homozygous mutant allele *3/*3. The distribution of genotypes, alleles, and metabolic types did not change significantly (P > 0.05) by sex, age, or type of stroke. In addition, no independent risk factors for clopidogrel resistance were found in this analysis. CONCLUSION: The distribution of CYP2C19 genotypes, allele frequencies, and metabolic types in patients with stroke in Han Chinese patients were not correlated with sex, age, or infarction type. The possibilities of hyperglycemia, hypercholesterolemia, hypertriglyceridemia, hypo-HDL-cholesterolemia, hyper-LDL-cholesterolemia and high blood pressure were not statistically associated with CYP2C19 genotypes. CYP2C19 gene polymorphism detection is recommended for patients who are available, and during treatment, the CYP2C19 genotype can be used to guide personalized precise medication use in patients with stroke.
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Citocromo P-450 CYP2C19 , Frequência do Gene , Acidente Vascular Cerebral , Humanos , Citocromo P-450 CYP2C19/genética , Masculino , Feminino , Acidente Vascular Cerebral/genética , Pessoa de Meia-Idade , Idoso , Clopidogrel/uso terapêutico , Genótipo , Adulto , Alelos , Resistência a Medicamentos/genética , Fatores de Risco , Polimorfismo GenéticoRESUMO
Two novel six-membered perimidocarbene (PIC)-based tetradentate Pt(II) complexes were designed and successfully synthesized. Systematical experimental and theoretical studies suggest that the PIC moiety greatly affects the frontier orbitals, as well as the photophysical and excited-state properties of the Pt(II) complexes. PtYK2 has a broad emission spectrum peaking at 576 nm with a shoulder band at 620 nm, along with a full width at half-maximum (FWHM) value of 100.0 nm at 77 K in 2-MeTHF; however, the emission spectrum is slightly red-shifted with a dominant peak at 610 nm and a FWHM value of 125.0 nm at room temperature in a poly(methyl methacrylate) (PMMA) film. Time-dependent-density functional theory and natural transition orbital analyses reveal that PtYK2 has a 3LC (3πPIC* â πPIC)-dominated character with an unexpectedly negligible contribution of 3MLCT transition (0.68%) in the T1 state, which results in a broad emission spectrum and a relatively low quantum efficiency of 7.4% in the PMMA film.
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We designed and synthesized a new Schiff base probe, which incorporated the salicylaldehyde-analogue α-cyanostilbene and benzophenone hydrazone by the imine linkage. Its chemical structure was verified by FT-IR, MALDI-TOF-MS, HR-MS and 1H/13C NMR technologies. It could exhibit a red fluorescence based on the synergistical effects of aggregation-induce emission (AIE), excited-state intramolecular proton transfer (ESIPT) and twisted intramolecular charge-transfer (TICT) in the aggregation or solid states. Interestingly, the TLC-based test strip loaded with the target compound showed the reversible fluorescence response to amine/acid vapor and on-site visual fluorescence quenching response to Fe3+. In THF/water mixtures (fw = 90%, 10 µM, pH = 7.4), the detection limit (DL) and the binding constant (Ka) of the developed probe towards Fe3+ were evaluated as 5.50 × 10- 8 M and 1.69 × 105, respectively. The developed probe was successfully applied for the detection of Fe3+ with practical, reliable, and satisfying results.
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Chromosome instability (CIN) is a common contributor driving the formation and progression of anaplastic thyroid cancer (ATC), but its mechanism remains unclear. The BUB1 mitotic checkpoint serine/threonine kinase (BUB1) is responsible for the alignment of mitotic chromosomes, which has not been thoroughly studied in ATC. Our research demonstrated that BUB1 was remarkably upregulated and closely related to worse progression-free survival. Knockdown of BUB1 attenuated cell viability, invasion, migration and induced cell cycle arrests, whereas overexpression of BUB1 promoted the cell cycle progression of papillary thyroid cancer cells. BUB1 knockdown remarkably repressed tumour growth and tumour formation of nude mice with ATC xenografts and suppressed tumour metastasis in a zebrafish xenograft model. Inhibition of BUB1 by its inhibitor BAY-1816032 also exhibited considerable anti-tumour activity. Further studies showed that enforced expression of BUB1 evoked CIN in ATC cells. BUB1 induced CIN through phosphorylation of KIF14 at serine1292 (Ser1292 ). Overexpression of the KIF14ΔSer1292 mutant was unable to facilitate the aggressiveness of ATC cells when compared with that of the wild type. Collectively, these findings demonstrate that the BUB1/KIF14 complex drives the aggressiveness of ATC by inducing CIN.
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Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Animais , Camundongos , Humanos , Carcinoma Anaplásico da Tireoide/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Camundongos Nus , Peixe-Zebra/metabolismo , Instabilidade Cromossômica , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Linhagem Celular Tumoral , Proteínas Oncogênicas/genética , Cinesinas/genéticaRESUMO
Recent investigations have suggested that abnormally elevated levels of HOCl may be tightly related to the severity of neuroinflammation. Although some successes have been achieved, fluorescent probes with far-red fluorescence emission and capable of detecting HOCl with high specificity in pure aqueous solution are still urgently needed. Herein, a responsive far-red fluorescent probe, DCI-H, has been constructed to monitor HOCl activity in vivo and in vitro. DCI-H could rapidly respond to HOCl within 120 s and had a low detection limit for HOCl of 1.5 nM. Importantly, physiologically common interfering species, except for HOCl, did not cause a change in the fluorescence intensity of DCI-HOCl at 655 nm. The results of confocal imaging demonstrated the ability of DCI-H to visualize endogenous HOCl produced by MPO-catalyzed H2O2/Cl- and LPS stimulation. With the assistance of DCI-H, upregulation of HOCl levels was observed in the mice model of LPS-induced neuroinflammation. Thus, we believed that DCI-H provided a valuable tool for HOCl detection and diagnosis of inflammation-related diseases.
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Zearalenone (ZEA), one of the usual mycotoxins, has been recognized in many areas and crops, posing a significant threat to the living organisms even to human beings. However, the mechanisms of locomotive defects remain unknown. Herein, zebrafish larvae was employed to investigate ZEA effects on developmental indexes, muscle and neural toxicity, apoptosis, transcriptome and motor behaviors of zebrafish larvae. Zebrafish larvae exposed to ZEA (0, 0.5, 1, 2 and 4 µM) showed no change in survival rate, but the malformation rate of zebrafish larvae increased dramatically manifesting with severe body bending and accomplished with adverse effects on hatching rate and body length. Moreover, the larvae manifested with defective muscle and abnormal neural development, resulting in decreased swimming ability, which probably due to the abnormal overactivation of apoptosis. And this was confirmed by enriched caspase 8-mediated apoptosis signaling pathway in the following transcriptome analysis. Meanwhile, there was a recovery in swimming behaviors in the larvae co-exposed in ZEA and caspase 8 inhibitor. These findings provide an important evidence for risk assessment and potential treatment target of ZEA exposure.
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Discinesias , Zearalenona , Animais , Humanos , Apoptose , Caspase 8/genética , Caspase 8/metabolismo , Larva , Músculos/metabolismo , Zearalenona/toxicidade , Zearalenona/metabolismo , Peixe-Zebra , Micotoxinas/química , Micotoxinas/metabolismoRESUMO
Pedestrian navigation methods based on inertial sensors are commonly used to solve navigation and positioning problems when satellite signals are unavailable. To address the issue of heading angle errors accumulating over time in pedestrian navigation systems that rely solely on the Zero Velocity Update (ZUPT) algorithm, it is feasible to use the pedestrian's motion constraints to constrain the errors. Firstly, a human step length model is built using human kinematic data collected by the motion capture system. Secondly, we propose the bipedal constraint algorithm based on the established human step length model. Real field experiments demonstrate that, by introducing the bipedal constraint algorithm, the mean biped radial errors of the experiments are reduced by 68.16% and 50.61%, respectively. The experimental results show that the proposed algorithm effectively reduces the radial error of the navigation results and improves the accuracy of the navigation.
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Pé , Pedestres , Humanos , Algoritmos , Movimento (Física) , Fenômenos BiomecânicosRESUMO
BACKGROUND: The glioblastoma has served as a valuable experimental model system for investigating the growth and invasive properties of glioblastoma. Aquaporin-1 (AQP1) in facilitating cell migration and potentially contributing to tumor progression. In this study, we analyzed the role of AQP1 overexpression in glioblastoma and elucidated the main mechanisms involved. METHODS: AQP1 overexpression recombinant vector was introduced into C6 rat glioma cells to construct an AQP1 overexpression C6 cell line, and its effect on cell viability and migration ability was detected by MTT and Transwell. RNA was extracted by Trizol method for gene sequencing and transcriptomics analysis, and the differentially expressed genes (DEGs) were enriched for up- and downregulated genes by Principal component analysis (PCA), and the molecular mechanism of AQP1 overexpression was analyzed in comparison with the control group using the NCBI GEO database. Statistical analysis was performed using Mann-Whitney paired two tailed t test. RESULTS: The cell viability of AQP1-transfected cell lines increased by 23% and the mean distance traveled increased by 67% compared with the control group. Quantitative analysis of gene expression showed that there were 12,121 genes with an average transcripts per million (TPM) value greater than 1. DEGs accounted for 13% of the genes expressed, with the highest correlation with upregulated genes being FOXO4 and MAZ, and the highest with downregulated genes being E2F TFs. CONCLUSIONS: AQP1 may be implicated in glioma formation by interacting with the transcriptional regulation networks involving the FOXO4, MAZ, and E2F1/2. These findings shed light on the potential significance of AQP1 in glioma pathogenesis and warrant further investigations to unravel the underlying molecular mechanisms.
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Background: The thyroid cancer subtype that occurs more frequently is papillary thyroid carcinoma (PTC). Despite a good surgical outcome, treatment with traditional antitumor therapy does not offer ideal results for patients with radioiodine resistance, recurrence, and metastasis. The evidence for the connection between iron metabolism imbalance and cancer development and oncogenesis is growing. Nevertheless, the iron metabolism impact on PTC prognosis is still indefinite. Methods: Herein, we acquired the medical data and gene expression of individuals with PTC from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) database. Typically, three predictive iron metabolism-related genes (IMRGs) were examined and employed to build a risk score (RS) model via the least absolute shrinkage and selection operator (LASSO) regression, univariate Cox, and differential gene expression analyses. Then we analyzed somatic mutation and immune cell infiltration among RS groups. We also validated the prognostic value of two IMRGs (SFXN3 and TFR2) by verifying their biological function through in vitro experiments. Results: Based on RS, all patients with PTC were stratified into low- and high-risk groups, where Kaplan-Meier analysis indicated that disease-free survival (DFS) in the high-risk group was much lower than in the low-risk group (P < 0.0001). According to ROC analysis, the RS model successfully predicted the 1-, 3-, and 5-year DFS of individuals with PTC. Additionally, in the TCGA cohort, a nomogram model with RS was developed and exhibited a strong capability to anticipate PTC patients' DFS. In the high-risk group, the enriched pathological processes and signaling mechanisms were detected utilizing the gene set enrichment analysis (GSEA). Moreover, the high-risk group had a significantly higher level of BRAF mutation frequency, tumor mutation burden, and immune cell infiltration than the low-risk group. In vitro experiments found that silencing SFXN3 or TFR2 significantly reduced cell viability. Conclusion: Collectively, our predictive model depended on IMRGs in PTC, which could be potentially utilized to predict the PTC patients' prognosis, schedule follow-up plans, and provide potential targets against PTC.
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Radioisótopos do Iodo , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/genética , Prognóstico , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/genética , FerroRESUMO
A novel alkoxycarbonyl-radical-triggered cascade cyclization of 1,7-enynes, with alkyloxalyl chlorides as the ester units, for the synthesis of benzo[j]phenanthridines is described. The reaction conditions exhibit excellent compatibility with a broad range of alkoxycarbonyl radical sources and realize the installation of an ester group in the polycyclic compound. This radical cascade cyclization reaction features excellent functional group tolerance, mild reaction conditions, and good to excellent yields.
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Amantadine exposure can alter biological processes in sea cucumbers, which are an economically important seafood in China. In this study, amantadine toxicity in Apostichopus japonicus was analyzed by oxidative stress and histopathological methods. Quantitative tandem mass tag labeling was used to examine changes in protein contents and metabolic pathways in A. japonicus intestinal tissues after exposure to 100 µg/L amantadine for 96 h. Catalase activity significantly increased from days 1 to 3 of exposure, but it decreased on day 4. Superoxide dismutase and glutathione activities were inhibited throughout the exposure period. Malondialdehyde contents increased on days 1 and 4 but decreased on days 2 and 3. Proteomics analysis revealed 111 differentially expressed proteins in the intestines of A. japonicus after amantadine exposure compared with the control group. An analysis of the involved metabolic pathways showed that the glycolytic and glycogenic pathways may have increased energy production and conversion in A. japonicus after amantadine exposure. The NF-κB, TNF, and IL-17 pathways were likely induced by amantadine exposure, thereby activating NF-κB and triggering intestinal inflammation and apoptosis. Amino acid metabolism analysis showed that the leucine and isoleucine degradation pathways and the phenylalanine metabolic pathway inhibited protein synthesis and growth in A. japonicus. This study investigated the regulatory response mechanisms in A. japonicus intestinal tissues after exposure to amantadine, providing a theoretical basis for further research on amantadine toxicity.
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Cellular functions of membrane proteins are strongly coupled to their structures and aggregation states in the cellular membrane. Molecular agents that can induce the fragmentation of lipid membranes are highly sought after as they are potentially useful for extracting membrane proteins in their native lipid environment. Toward this goal, we investigated the fragmentation of synthetic liposome using hydrophobe-containing polypeptoids (HCPs), a class of facially amphiphilic pseudo-peptidic polymers. A series of HCPs with varying chain lengths and hydrophobicities have been designed and synthesized. The effects of polymer molecular characteristics on liposome fragmentation are systemically investigated by a combination of light scattering (SLS/DLS) and transmission electron microscopy (cryo-TEM and negative stained TEM) methods. We demonstrate that HCPs with a sufficient chain length (DPn ≈ 100) and intermediate hydrophobicity (PNDG mol % = 27%) can most effectively induce the fragmentation of liposomes into colloidally stable nanoscale HCP-lipid complexes owing to the high density of local hydrophobic contact between the HCP polymers and lipid membranes. The HCPs can also effectively induce the fragmentation of bacterial lipid-derived liposomes and erythrocyte ghost cells (i.e., empty erythrocytes) to form nanostructures, highlighting the potential of HCPs as novel macromolecular surfactants toward the application of membrane protein extraction.
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Lipossomos , Polímeros , Lipossomos/química , Membrana Celular/metabolismo , Polímeros/química , Proteínas de Membrana , Lipídeos/química , Interações Hidrofóbicas e HidrofílicasRESUMO
Low intrinsic conductivity and structural instability of MoS2 as an anode of sodium-ion batteries limit the liberation of its theoretical capacity. Herein, density functional theory simulations for the first time optimize MoS2 interlayer distance between 0.80 and 1.01 nm for sodium storage. 1-Butyl-3-methyl-imidazolium acetate ([BMIm]Ac) induces cellulose oligomers to intercalate MoS2 interlayers for achieving controllable distance by changing the mass ratio of cellulose to [BMIm]Ac. Based on these findings, porous carbon loading the interlayer-expanded MoS2 allowing Na+ to insert with fast kinetics is synthesized. A carbon layer derived from [BMIm]Ac and cellulose coating the composite prevents the MoS2 from contacting electrolytes, leading to less sulfur loss for a more reversible specific capacity. Meanwhile, MoS2 and carbon have a strong interfacial connection through MoN binding, contributing to enhanced structural stability. As expected, while cycling 250 times at 0.1 A g-1 , the MoS2 -porous carbon composite displays an optimal reversible capacity at 517.79 mAh g-1 as a sodium-ion batteries anode. The cyclic test of 1.0 A g-1 also shows considerable stability (310.74 mAh g-1 after 1000 cycles with 86.26% retentive capacity). This study will open up new possibilities of modifying MoS2 that serves as an applicable material as sodium-ion battery anode.
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Inorganic arsenic (iAs) is a widespread contaminant in marine environments, which is present in two different oxidation states (arsenate (AsV) and arsenite (AsIII)) that have complex toxic effects on marine organisms. The scallop Chlamys farreri (C. farreri) accumulates high levels of As and is a suitable bioindicator of As. In this report, we integrated transcriptomics and metabolomics to investigate genetic and metabolite changes and functional physiological disturbances in C. farreri exposured to inorganic arsenic. Physiological indicators antioxidant factors and cell apoptosis analysis macroscopically corroborated the toxic effects of inorganic arsenic revealed by omics results. Toxic effects of inorganic arsenic on C. farreri were signaling-mediated, causing interference with a variety of cell growth and small molecule metabolism. The results provide evidence that inorganic arsenic disrupts the physiological functions of bivalves, highlighting the correlations between different metabolic pathways and providing new insights into the toxic effects of environmental pollutants on marine organisms.