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As a mainstream technology for recycling spent lithium-ion batteries, direct regeneration is rapidly developed due to its high efficiency and green characteristics. However, efficient reuse of spent LiNixCoyMn1- x - yO2 cathode is still a significant challenge, as the rock salt/spinel phase on the surface hinders the Li replenishment and phase transformation to the layered structure. In this work, the fundamental understanding of the repair mechanism is confirmed that the oxidizing atmosphere is the crucial factor that can greatly improve the rate and degree of phase restoration. Particularly, a ternary-component molten salt system (LiOH-Li2CO3-LiNO3) is proposed for direct regeneration of LiNi0.5Co0.2Mn0.3O2 (NCM523), which can in situ generate the strong oxidizing intermediate of superoxide radicals. Additionally, it shows a liquid-like reaction environment at a lower temperature to acceclerate the transport rate of superoxide-ions. Therefore, the synergistic effect of LiOH-Li2CO3-LiNO3 system can strengthen the full restoration of rock salt/spinel phases and achieve the complete Li-supplement. As anticipated, the regenerated NCM523 delivers a high cycling stability with a retention of 91.7% after 100 cycles, which is even competitive with the commercial NCM523. This strategy provides a facile approach for the complete recovery of layer structure cathode, demonstrating a unique perspective for the direct regeneration of spent lithium-ion batteries.
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As a non-traditional sample matrix, feather samples can be used to effectively monitor antibiotic addition and organismal residue levels in poultry feeding. Therefore, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed to simultaneously determine the residue levels of 26 quinolones in poultry feathers. The feather samples were extracted by sonication with a 1% formic acid and acetonitrile mixture in a water bath at 50 °C for 30 min, purified by the adsorption of multiple matrix impurities, dried with nitrogen, redissolved, and analyzed by UPLC-MS/MS. The linearity, limit of detection (LOD), limit of quantification (LOQ), recovery and precision were calculated. The 26 antibiotics demonstrated good linearity in the linear range. The recoveries and coefficients of variation were 78.9-110% and <13.7% at standard spiked levels of 10, 100 and 200 µg/kg, respectively. The LOD and LOQ were 0.12-1.31 and 0.96-2.60 µg/kg, respectively. The method also successfully identified quinolone residues in 50 poultry feather samples. The results showed that quinolones can accumulate and stabilize for a certain period of time after transferring from the body to the feathers of poultry.
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Quinolonas , Animais , Cromatografia Líquida , Quinolonas/análise , Aves Domésticas , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Plumas/química , Antibacterianos/análise , Extração em Fase SólidaRESUMO
2D layered Sn-based materials have attracted enormous attention due to their remarkable performance in sodium-ion batteries. Nevertheless, this promising candidate involves a complex Na+ -storage process with multistep conversion-alloying reactions, which induces the uneven dispersion of heterogeneous intermediate accompanied by severe agglomeration of metallic Sn0 , inescapably resulting in poor reaction reversibility with sluggish rate capability and inferior cyclic lifespan. Herein, a delicately layered heterostructure SnSSe/C consisting of defect-rich SnSSe and graphene is designed and successfully achieved via a facile hydrothermal process. The equal anionic substitution of Se in SnSSe crystal can trigger numerous defects, which can not only facilitate Na+ diffusion but also accelerate the nucleation process by inducing quantum-dot-level uniform distribution of heterogeneous intermediates, Na2 Se/Na2 S and Sn0 . Concurrently, in situ formed uniform Na2 Se/Na2 S grain boundaries confined by this unique layered heterostructure may effectively suppress the agglomeration of metallic Sn0 nanograins and boost the reversibility of conversion-alloying reaction. As a result, the SnSSe/C displays significant improvement in Na-storage performance, in terms of remarkable rate capability and ultralong cycling lifespan. This work, focusing on controlling intermediate distribution, provides an effective strategy to boost reaction reversibility, which can be wildly employed in conversion-based electrodes for energy storage regions.
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Fluorene-9-bisphenol (BHPF), which has been used as a substitute for bisphenol A (BPA) in consumer goods and industrial products, can be detected in environmental media and human urine. BHPF has been reported to have endocrine-disrupting effects, whereas deleterious effects on steroidogenesis in H295R cells and underlying mechanisms are still unclear. Here, we investigated effects of BHPF on steroidogenesis using human adrenocortical carcinoma cells (H295R). Cytotoxicity was initially assessed and half-maximal inhibitory concentration (IC50) was determined based on proliferation of cells. Responses of four steroid hormones, aldosterone, cortisol, testosterone and 17ß-estradiol (E2), and ten critical genes, StAR, HMGR, CYP11A1, CYP11B1, CYP11B1, HSD3B2, CYP21, CYP17, 17ß-HSD, and CYP19, involved in steroidogenesis after exposure to non-cytotoxic concentrations of BHPF were determined in the presence or absence of 100 µM dbcAMP. Adenylate cyclase (AC) activity, intracellular concentrations of cAMP, PKA activity and amounts of steroidogenic factor-1 (SF-1) gene and expressions of proteins were determined to elucidate underlying mechanisms of effects on steroidogenesis. BHPF was cytotoxic to H295R cells in a dose- and time-dependent manner. Effects on production of hormones results demonstrated that exposure to greater concentrations of BHPF inhibited productions of aldosterone, cortisol, testosterone and E2 by down-regulation of steroidogenic genes. Inhibition of AC activity, intercellular cAMP content and PKA activity after exposure to BHPF implied that the AC/cAMP/PKA signaling pathway was involved in BHPF-induced suppression of steroidogenesis in H295R cells. Additionally, BHPF inhibited steroidogenesis and expressions of steroidogenic genes via decreasing expression of SF-1 protein, both in basal and dbcAMP-induced treatment. These results contributed to understanding molecular mechanisms of BHPF-induced effects on steroidogenesis and advancing the comprehensive risk assessment of BPs.
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Aldosterona , Hidrocortisona , Aldosterona/metabolismo , Compostos Benzidrílicos , Bucladesina , Linhagem Celular Tumoral , Fluorenos , Humanos , Hidrocortisona/metabolismo , Fenóis , Transdução de Sinais , Esteroide 11-beta-Hidroxilase/metabolismo , Testosterona/metabolismoRESUMO
In this study, a method, based on an ultraperformance liquid chromatography coupled with high-field quadrupole orbitrap high-resolution mass spectrometry (UHPLC-QE-HF-HRMS) platform, was established for the trace determination of three major avenanthramides (AVNs). The MS conditions for determining the AVNs were optimized, and the cracking methods of avenanthramides were analyzed. The linear range of the results and the correlation coefficient were 1−2000 µg/L and >0.996, respectively. Further, the established method was employed for the determination of the AVN contents of oats at different germination times, and the results indicated that the AVN contents of Zaohua and Bayou oats increased 19.26 and 6.09 times, respectively, after germination. The total AVN content of both oat varieties reached a maximum on the fifth day of germination (153.51 ± 4.08 and 126.30 ± 3.33 µg/g for the Zaohua and Bayou oats, respectively). Furthermore, this study investigated the antiallergic and antioxidant activities of the germinated oats via hyaluronidase inhibition and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging assays. The antiallergic and DPPH-scavenging abilities of the ungerminated forms of both oat varieties were weaker. However, on the fifth day of germination, the inhibition rate of anthranilamide hyaluronidase reached 72.7% and 67.3% for the Zaohua and Bayou oat varieties, respectively. The antiallergic abilities of the oats increased significantly on the fifth day of germination in terms of their antiallergic capacities and DPPH clearance (82.67% and 77.64% for the Zaohua and Bayou oats, respectively), and the two indicators exhibited similar trends. These findings demonstrated that AVNs exhibit good antisensitivity and antioxidation properties, and the antisensitivity effect correlated positively with the AVN content.
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Antialérgicos , Avena , Antialérgicos/análise , Antioxidantes/química , Avena/química , Grão Comestível/química , Germinação , Hialuronoglucosaminidase , ortoaminobenzoatos/químicaRESUMO
BACKGROUND: H. pylori is closely related to the occurrence and development of various digestive gastritis, peptic ulcer and mucosa-associated lymphoid tissue (MALT) lymphoma. H. pylori is also a class I carcinogen of gastric cancer. VacA is the only exocrine toxin of H. pylori, which plays a very important role in the pathogenesis of H. pylori. The production of VacA in natural circumstances is complex with heavy workload and low yield. Therefore, it is very important to obtain recombinant VacA protein which is stable and biologically active. This study therefore aims to explore the expression, purification and stable storage of VacA toxin of H. pylori in E.coli, and to provide experimental basis for further exploration of the role of VacA in H. pylori -induced inflammation of cancer. RESULTS: A 2502-bp fragment and VacA gene were identified. An 89.7-kDa VacA34-854 recombinant protein was expressed and purified from the recombinant engineering bacteria and was preserved stably in 50 mM acetic acid buffer (pH 2.9). The amount of the recombinant protein was larger in the inclusion bodies than in the supernatant. In addition, after a 24-h culture with VacA recombinant protein, GES-1 cells demonstrated evidence of apoptosis including early nuclear immobilization and clustering under inverted microscope and TEM. It was found that VacA recombinant protein induced apoptosis by TUNEL assay. CONCLUSIONS: A VacA recombinant protein that is stably and highly expressed and possesses pro-apoptotic activity is successfully constructed. The protein is stably preserved in 50 mM acetic acid buffer (pH 2.9).
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Apoptose , Proteínas de Bactérias/genética , Helicobacter pylori/genética , Vacúolos/metabolismo , Proteínas de Bactérias/metabolismo , Linhagem Celular , Células Epiteliais/microbiologia , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
OBJECTIVE: To determine the accuracy of endoscopic ultrasonography (EUS) in the diagnosis of upper gastrointestinal submucosal lesions (SMLs). METHODS: This was a retrospective study involving patients diagnosed with SMLs using EUS and confirmed by histopathology from November 2014 to December 2020 at The Third Xiangya Hospital of Central South University. RESULTS: A total of 231 patients with SMLs were examined by EUS. Histologically, 107 lesions were stromal tumors, and 75 lesions were leiomyomas. Stromal tumors were mainly located in the stomach (89.7%), and leiomyomas were predominantly seen in the esophagus (69.3%). The diagnostic accuracy of EUS for stromal tumors and leiomyomas was 80.4% and 68.0%, respectively. The diagnostic accuracy was highest for lesions located in the muscularis mucosa. The mean diameter of stromal tumors measured using EUS was significantly larger than that of leiomyomas (21.89 mm vs. 12.35 mm, p < 0.001). Stromal tumors and leiomyomas originated mainly from the muscularis propria (94.4%) and the muscularis mucosa (56.0%), respectively. Compared with the very low-risk and low-risk groups of stromal tumors according to the National Institute of Health guidelines, the intermediate-risk and high-risk groups were more likely to have a lesion > 3 cm (p < 0.001) and a surface ulcer (p < 0.01) identified by EUS. CONCLUSIONS: EUS has good diagnostic value for the diagnosis of upper gastrointestinal SMLs based on the lesion size and the muscle layer of origin. The diagnostic accuracy of EUS lesions is related to the origin, and the diagnostic accuracy is greatest in the mucosal muscularis layer. Stromal tumors > 3 cm and a surface ulcer on EUS are likely to be intermediate or high risk for invasion.
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Leiomioma , Trato Gastrointestinal Superior , Diagnóstico Diferencial , Endossonografia , Humanos , Leiomioma/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Mixed-organic-cation FAxMA1-xPbI3 films were prepared using a one-step solution deposition method in ambient air. The formamidinium (FA+) fraction 'x' was varied from 0.1 to 1 by changing the amounts of formamidinium iodide (FAI) and methylammonium iodide (MAI) in the precursor solution. Perovskite solar cells (PSCs) with a structure of FTO glass/compact TiO2/mesoporous TiO2/FAxMA1-xPbI3/carbon electrode were designed and fabricated. The effects of the FA+ fraction 'x' on the structure, morphology and optical properties of the FAxMA1-xPbI3 films as well as the photovoltaic performance of PSCs were studied. The results showed that the photovoltaic inactive δ-phase FAPbI3 can be formed in the presence of high contents of FA+ (x = 0.8 and 1.0). The band gap of FAxMA1-xPbI3 decreased from 1.58 eV to 1.49 eV when the FA+ fraction x increased from 0.1 to 1. The PSCs based on FA0.4MA0.6PbI3 exhibited an optimal photovoltaic performance, yielding Voc of 0.8 V, Jsc of 22.84 mA cm-2, FF of 0.48 and PCE of 8.77%.
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OBJECTIVE: To explore whether transumbilical endoscopic surgery (TUES) can effectively and safely elucidate the causes of ascites of unknown origin.â© Methods: A total of 23 consecutive patients with ascites of unknown origin who undertook TUES procedures in the Department of Gastroenterology of The Third Xiangya Hospital of Central South University between January 2014 and January 2016 were retrospectively investigated. Clinical manifestations, laboratory examinations and findings from radiological examinations and endoscopic investigations were noted before the procedure. Conditions of the abdominal cavity under endoscope, final diagnosis and outcome of patients were carefully recorded.â© Results: TUES procedure was successfully performed in all 23 patients with an operation time of (58.2±13.9) min. Twenty-two patients were undertaken biopsy on the nodules or masses that found in the abdominal cavity. Definite diagnoses were established in the overwhelming majority of patients (22/23). The most common causes of ascites for the 23 cases was tuberculosis (8 cases), followed by peritoneal carcinomatosis (6 cases), and pseudomyxoma peritonei (5 cases). Operation-related complications, such as postoperative bleeding, perforation, peritonitis, intraabdominal chronic abscesses, were not observed, except one case showed a transient moderate fever in 24 hours after operation. No mortality related to TUES occurred. We concluded that TUES was a feasible, economic and minimally invasive approach to access the peritoneal cavity.â© Conclusion: TUES combinated with biopsy can effectively elucidate the causes of ascites of unknown origin.
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Ascite , Humanos , Laparoscopia , Duração da Cirurgia , Pseudomixoma Peritoneal , Estudos RetrospectivosRESUMO
CONTEXT: Atractylenolide I (AT-I), an active compound isolated from Atractylodes macrocephala Koidz (Compositae), shows several pharmacological activities. OBJECTIVE: Our present study is designed to investigate the protective effect of AT-I on systemic inflammation in the mouse model of sepsis created by cecal ligation and puncture (CLP), and explore the possible mechanism. MATERIALS AND METHODS: Sepsis mouse model was established by CLP, and the tested dosages of AT-I were 10, 20, and 40 mg/kg (ip). Pro-inflammatory cytokines in serum (TNF-α, IL-1ß and IL-6) were determined by the ELISA method; serum lipopolysaccharide (LPS) level was measured by the Limulus Amebocyte Lysate (LAL) test; white blood cells (WBC) were counted by Blood cell analyzer; contents of alanine transaminase (ALT), aspartate transarninase (AST), creatinine (Cre), and blood urea nitrogen (BUN) in serum were determined by automatic biochemistry analyzer. For survival rate tests, CLP mice were observed within 7 days, and body temperature was measured at 0, 4, 8, 12, 24, 48 and 72 h after surgery. RESULTS: Our results indicated that AT-I significantly increased the survival rate of mice with sepsis (p < 0.05), whereas the WBCs and levels of LPS, pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6), ALT, AST, Cre, and BUN decreased significantly after treatment with AT-I (p < 0.05). CONCLUSION: In conclusion, the AT-I ameliorates sepsis syndrome by reduction of pro-inflammatory cytokines and LPS, and provides an improvement in liver and kidney functions.
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Anti-Inflamatórios/farmacologia , Ceco/cirurgia , Inflamação/prevenção & controle , Lactonas/farmacologia , Sepse/prevenção & controle , Sesquiterpenos/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Nitrogênio da Ureia Sanguínea , Ceco/microbiologia , Creatinina/sangue , Citocinas/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inflamação/sangue , Inflamação/imunologia , Inflamação/microbiologia , Mediadores da Inflamação/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Ligadura , Lipopolissacarídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Punções , Sepse/sangue , Sepse/imunologia , Sepse/microbiologia , Fatores de TempoRESUMO
BACKGROUND: Astaxanthin, a xanthophyll carotenoid, holds exceptional promise as an antioxidant, anti-inflammatory, and anticancer agent. No evidence has been published whether it has protective effects on sepsis. The study aimed to investigate the potential effects of astaxanthin on sepsis and multiple organ dysfunctions. MATERIALS AND METHODS: Sepsis was induced by cecal ligation and puncture (CLP) in Sprague-Dawley rats. Animals subjected to CLP and sham-operated control rats were given vehicle or astaxanthin 100 mg/kg/d by oral gavage for 7 d before the operation. The rats were killed at the indicated time points, and the specimen was collected. Cytokines and multiorgan injury-associated enzymatic and oxidative stress indicators were investigated. Multiorgan tissues were assessed histologically, the peritoneal bacterial load and the 72-h survival was observed too. RESULTS: Sepsis resulted in a significant increase in serum tumor necrosis factor-α, interleukin-1ß, and interleukin-6 levels showing systemic inflammatory response; it also caused a remarkable decrease in the superoxide dismutase activity and a significant increase in the malondialdehyde content showing oxidative damage; sepsis caused a great increase in organ injury-associated indicators, including blood urea nitrogen, creatinine, lactate dehydrogenase, creatine kinase isoenzyme-MB isotype, alanine aminotransferase, and aspartate aminotransferase, which was confirmed by histologic examination. And there was a dramatical increase of colony-forming units in the peritoneal cavity in septic rats. Astaxanthin reversed these inflammatory and oxidant response, alleviated the organ injury, reduced the peritoneal bacterial load, and improved the survival of septic rats induced by CLP. CONCLUSIONS: Astaxanthin exerts impressively protective effects on CLP-induced multiple organ injury. It might be used as a potential treatment for clinical sepsis.
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Insuficiência de Múltiplos Órgãos/prevenção & controle , Sepse/tratamento farmacológico , Animais , Creatina Quinase Forma MB/sangue , Citocinas/sangue , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Sepse/imunologia , Xantofilas/uso terapêuticoRESUMO
In the present study, we aimed to explore the effects of periostin, a cell adhesion protein, on chemoresistance in colon cancer cells. Reverse-transcription polymerase chain reaction and Western blot analyses were employed to detect periostin expression in SW480 and HT-29 colon cancer cells treated with oxaliplatin or fluorouracil (5-FU). Small interfering RNA was used to downregulate endogenous periostin. Annexin-V/propidium iodide staining was performed to analyze the effects of periostin on drug-induced apoptosis. The results showed that treatment with oxaliplatin or 5-FU elevated both the mRNA and protein levels of periostin in SW480 and HT-29 cells. Silencing of periostin significantly (P < 0.01) augmented drug-induced apoptosis in colon cancer cells, coupled with enhanced cleavage of caspase-3 and poly(ADP-ribose) polymerase. Mechanistic studies revealed that periostin silencing significantly (P < 0.01) suppressed the expression of survivin, an antiapoptotic protein in colon cancer cells. Enforced expression of survivin repressed drug-induced apoptosis in periostin-depleted SW480 and HT-29 cells. Additionally, periostin overexpression increased the expression of survivin and the phosphorylation of Akt, which was reversed by pretreatment with the phosphatidylinositol 3-kinase (PI3K)-specific inhibitor LY294002. Taken together, our data demonstrate that periostin induces chemoresistance in colon cancer cells through activation of the PI3K/Akt/survivin pathway.
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Moléculas de Adesão Celular/farmacologia , Neoplasias do Colo/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Moléculas de Adesão Celular/antagonistas & inibidores , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Fluoruracila/farmacologia , Humanos , Compostos Organoplatínicos/farmacologia , OxaliplatinaRESUMO
OBJECTIVE: To evaluate the effect of the bone marrow mesenchymal stem cells (BMSCs) transplant through peripheral vein, portal vein and hepatic artery into liver under the condition of constant magnetic field and to analyze the therapeutic effect on liver function recovery. METHODS: BMSCs were isolated, purified and induced to differentiate into liver-like cells, which were double labeled by Feridex-GFP. The double-labeled BMSCs were transplanted into liver through different ways including peripheral vein, portal vein and hepatic artery with or without constant magnetic field in vitro. The rats were sacrificed at the 1st, 2nd, 3rd and 4th week after the transplant. ALB, ALT, AST were tested. The liver tissue biopsy was collected. GFP-positive cells in liver were observed by fluorescence microscopy. RESULTS: Double-labeled BMSCs could be transplanted into liver through all ways. GFP expression was found in liver in all groups at the 4th week and the liver functions were improved. Based on the long term efficacy, the liver functions recovered more rapidly in the portal vein + constant magnetic field group and the hepatic artery + constant magnetic field group. CONCLUSION: BMSCs transplantation can reduce acute liver damage. The first choice for BMSCs transplantation was via portal vein or hepatic artery under the condition of constant magnetic field. The second choice was via peripheral vein alone or under the condition of constant magnetic field.
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Dextranos , Hepatopatias/terapia , Campos Magnéticos , Nanopartículas de Magnetita , Transplante de Células-Tronco Mesenquimais , Animais , Proteínas de Fluorescência Verde , RatosRESUMO
BACKGROUND: An increasing number of ß2-adrenergic agonists are illicitly used for growth promoting and lean meat increasing in animal husbandry in recent years, but the development of analytical methods has lagged behind these emerging drugs. RESULTS: Here, we designed and developed an ultrasound probe enhanced enzymatic hydrolysis reactor for quick separation and simultaneously quantification of 22 ß2-adrenergic agonists in animal urine and livestock wastewater. Owing to the enhancement of the conventional enzymatic digestion through the ultrasound acoustic probe power, only 2 min was required for the comprehensively separation of ß2-adrenergic agonists from the sample matrices, making it a much more desirable alternative tool for high-throughput investigation. The swine, bovine and sheep urines (n = 287), and livestock wastewater (n = 15) samples, collected from both the north and south China, were examined to demonstrate the feasibility and capability of the proposed approach. Six kinds of ß2-adrenergic agonists (clenbuterol, salbutamol, ractopamine, terbutaline, clorprenaline and cimaterol) were found in animal urines, with concentrations ranged between 0.056 µg/L (terbutaline) and 5.79 µg/L (clenbuterol). Up to nine ß2-adrenergic agonists were detected in wastewater samples, of which four were found in swine farms and nine in cattle/sheep farms, with concentration levels from 0.069 µg/L (tulobuterol) to 2470 µg/L (clenbuterol). SIGNIFICANCE: Interestingly, since ß2-adrenergic agonists are usually considered to be abused mainly in the pig farms, our data indicate that both the detection frequencies and concentrations of these agonists in the ruminant farms were higher than the pig farms. Furthermore, the findings of this work indicated that there is a widespread occurrence of ß2-adrenergic agonists in livestock farms, especially for clenbuterol and salbutamol, which may pose both food safety and potential ecological risks. We recommend that stricter controls should be adopted to prevent the illegally usage of these ß2-adrenergic agonists in agricultural animals, especially ruminants, and they should also be removed before discharging to the environment.
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Águas Residuárias , Animais , Águas Residuárias/química , Águas Residuárias/análise , Hidrólise , Suínos , Bovinos , Gado , Agonistas de Receptores Adrenérgicos beta 2/urina , Ovinos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/urina , Poluentes Químicos da Água/metabolismoRESUMO
The instability in the structural integrity caused by interfacial issues is commonly regarded as the primary drawback of Ni-rich layered cathode materials (LiNixCoyMn1-x-yO2, where x ≥ 0.8), which must be addressed before their commercial application. Herein, a novel multiple-function surface modification strategy is proposed based on the single crystal structure to in-situ achieve the construction of a coating layer and surface doping with Ce element to enhance the structural stability of the LiNi0.88Co0.09Mn0.03O2 (NCM). Notably, the introduction of Ce-O bonding adjusts the local oxygen coordination to achieve a more stabilized structure of the oxygen framework, which inhibits the evolution of lattice oxygen and enhances conductivity. Additionally, by benefiting from the in-situ synthesized coating layer of LixCeO2, the occurrence of side reactions on the surface is effectively alleviated, resulting in a reduction in electrode polarization. Combined with comprehensive electrochemical tests, it is confirmed that the improved electrochemical performance originates from the reduction of the detrimental H2-H3 phase transition and enhanced conductivity. As expected, the modified material with 1 wt% content of Ce (NCM@Ce) exhibits a high initial discharge capacity of 196.3 mAh g-1 with a capacity retention of 79.7 % after 200 cycles, and its energy density reaches 574.3 Wh kg-1 after 200 cycles.
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Organophosphate triesters (tri-OPEs) threaten human health through dietary exposure, but little is known about their feed-to-food transfer and in vivo behavior in farm animals. Herein 135 laying hens were fed with contaminated feed (control group, low-level group and high-level group) to elucidate the bioaccumulation, distribution, and metabolism of the six most commonly reported tri-OPEs. The storage (breast muscle), metabolism and mobilization (liver and blood) and non-invasive (feather) tissues were collected. The exposure-increase (D1â¼14) and depuration-decrease (D15â¼42) trends indicated that feed exposure caused tri-OPE accumulation in animal tissues. Tissue-specific and moiety-specific behavior was observed for tri-OPEs. The highest transfer factor (TF) and transfer rate (TR) were observed in liver (TF: 14.8%â¼82.3%; TR: 4.40%â¼24.5%), followed by feather, breast muscle, and blood. Tris(2-chloroisopropyl) phosphate (TCIPP) had the longest half-life in feather (72.2 days), while triphenyl phosphate (TPhP) showed the shortest half-life in liver (0.41 days). Tri-OPEs' major metabolites (organophosphate diesters, di-OPEs) were simultaneously studied, which exhibited dose-dependent and time-dependent variations following administration. In breast muscle, the inclusion of di-OPEs resulted in TF increases of 735%, 1108%, 798%, and 286% than considering TCIPP, tributyl phosphate, tris(2-butoxyethyl) phosphate and tris(2-ethylhexyl) phosphate alone. Feather was more of a proxy of birds' long-term exposure to tri-OPEs, while short-term exposure was better reflected by di-OPEs. Both experimental and in silico modeling methods validated aryl-functional group facilitated the initial accumulation and metabolism of TPhP in the avian liver compared to other moiety-substituted tri-OPEs.
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Galinhas , Retardadores de Chama , Animais , Feminino , Humanos , Bioacumulação , Galinhas/metabolismo , Ésteres/metabolismo , Biotransformação , Organofosfatos/metabolismo , Fosfatos , Retardadores de Chama/análise , China , Monitoramento AmbientalRESUMO
Single-crystal Ni-rich cathodes offer promising prospects in mitigating intergranular microcracks and side reaction issues commonly encountered in conventional polycrystalline cathodes. However, the utilization of micrometer-sized single-crystal particles has raised concerns about sluggish Li+ diffusion kinetics and unfavorable structural degradation, particularly in high Ni content cathodes. Herein, we present an innovative in situ doping strategy to regulate the dominant growth of characteristic planes in the single-crystal precursor, leading to enhanced mechanical properties and effectively tackling the challenges posed by ultrahigh-nickel layered cathodes. Compared with the traditional dry-doping method, our in situ doping approach possesses a more homogeneous and consistent modifying effect from the inside out, ensuring the uniform distribution of doping ions with large radius (Nb, Zr, W, etc). This mitigates the generally unsatisfactory substitution effect, thereby minimizing undesirable coating layers induced by different solubilities during the calcination process. Additionally, the uniformly dispersed ions from this in situ doping are beneficial for alleviating the two-phase coexistence of H2/H3 and optimizing the Li+ concentration gradient during cycling, thus inhibiting the formation of intragranular cracks and interfacial deterioration. Consequently, the in situ doped cathodes demonstrate exceptional cycle retention and rate performance under various harsh testing conditions. Our optimized in situ doping strategy not only expands the application prospects of elemental doping but also offers a promising research direction for developing high-energy-density single-crystal cathodes with extended lifetime.
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OBJECTIVE: To investigate how ceramide mediates the effects of high-glucose-induced inhibition of the Akt/endothelial nitric oxide synthase (eNOS) signalling pathway in human vascular endothelial cells (HUVECs). MATERIALS AND METHODS: NO levels were determined by ELISA. Endogenous ceramide levels were determined using a liquid chromatography-mass spectrometry assay. Akt and eNOS protein expressions were determined by Western blotting. RESULTS: High-glucose levels induce ceramide accumulation in a dose- and time-dependent manner (p<0.05). We also show that exposure of HUVECs to high-glucose conditions inhibits the insulin-mediated activation of Akt/eNOS signalling and the subsequent NO generation in a dose-dependent manner (p<0.05). Preventing de novo ceramide synthesis attenuated the antagonistic effects of high-glucose levels on the Akt/eNOS signalling pathway (p<0.05); conversely, inducing ceramide build-up augmented the inhibitory effects of high-glucose levels on the Akt/eNOS signalling pathway (p<0.05). CONCLUSION: Ceramide is both necessary and sufficient for mediating the inhibition of the Akt/eNOS signalling pathway by high-glucose levels in endothelial cells.
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Ceramidas/farmacologia , Células Endoteliais/efeitos dos fármacos , Glucose/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Proteína Oncogênica v-akt/metabolismo , Células Cultivadas , Ceramidas/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Insulina/farmacologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Proteína Oncogênica v-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Fatores de TempoRESUMO
We report the improved kinetic mechanism of a nickel-rich LiNi0.84Mn0.10Co0.03Al0.03O2 cathode. The important role of Co/Al in inhibiting cation disorder to increase the lithium ion diffusion rate is revealed. Impressively, it retains an excellent capacity retention of 76.8% after 200 cycles under the high-rate condition (5C).
Assuntos
Alumínio , Cobalto , Cinética , Eletrodos , DifusãoRESUMO
A method based on a multi-mechanism impurity adsorption and ultra-performance liquid chromatography-tandem mass spectrometry was established to detect fipronil and four of its metabolites in chicken feathers. This method was successfully applied to the depletion study of fipronil in feathers of laying hens. Fipronil and two metabolites were found in feathers during treatment. Fipronil concentrations in feathers increased during medication and then regularly decreased during withdrawal, and they were still detected on the 14th day after withdrawal. High residue concentrations were also present in feathers on day 23 of the experimental period. Pollution sources of fipronil can be inferred on the basis of the residue ratio of fipronil metabolites from different pollution modes. Result shows that feathers were an effective matrix for residue monitoring and risk analysis of fipronil in animals and the environment.