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1.
Plant Physiol ; 195(3): 2195-2212, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38589996

RESUMO

Efficient uptake, translocation, and distribution of Cu to rice (Oryza sativa) spikelets is crucial for flowering and yield production. However, the regulatory factors involved in this process remain unidentified. In this study, we isolated a WRKY transcription factor gene induced by Cu deficiency, OsWRKY37, and characterized its regulatory role in Cu uptake and transport in rice. OsWRKY37 was highly expressed in rice roots, nodes, leaf vascular bundles, and anthers. Overexpression of OsWRKY37 promoted the uptake and root-to-shoot translocation of Cu in rice under -Cu condition but not under +Cu condition. While mutation of OsWRKY37 significantly decreased Cu concentrations in the stamen, the root-to-shoot translocation and distribution ratio in brown rice affected pollen development, delayed flowering time, decreased fertility, and reduced grain yield under -Cu condition. yeast one-hybrid, transient co-expression and EMSAs, together with in situ RT-PCR and RT-qPCR analysis, showed that OsWRKY37 could directly bind to the upstream promoter region of OsCOPT6 (copper transporter) and OsYSL16 (yellow stripe-like protein) and positively activate their expression levels. Analyses of oscopt6 mutants further validated its important role in Cu uptake in rice. Our study demonstrated that OsWRKY37 acts as a positive regulator involved in the uptake, root-to-shoot translocation, and distribution of Cu through activating the expression of OsCOPT6 and OsYSL16, which is important for pollen development, flowering, fertility, and grain yield in rice under Cu deficient conditions. Our results provide a genetic strategy for improving rice yield under Cu deficient condition.


Assuntos
Cobre , Flores , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Fatores de Transcrição , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Oryza/metabolismo , Cobre/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Flores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Fertilidade/genética
2.
Angew Chem Int Ed Engl ; 63(33): e202407417, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38818653

RESUMO

Realizing durative dense, dendrite-free, and no by-product deposition configuration on Zn anodes is crucial to solving the short circuit and premature failure of batteries, which is simultaneously determined by the Zn interface chemistry, electro-reduction kinetics, mass transfer process, and their interaction. Herein, this work unmasks a domino effect of the ß-alanine cations (Ala+) within the hydrogel matrix, which effectively triggers the subsequent electrostatic shielding and beneficial knock-on effects via the specifical adsorption earliest event on the Zn anode surface. The electrostatic shielding effect regulates the crystallographic energetic preference of Zn deposits and retards fast electro-reduction kinetics, thereby steering stacked stockier block morphology and realizing crystallographic optimization. Meanwhile, the mass transfer rate of Zn2+ ions was accelerated via the SO4 2- anion immobilized caused by Ala+ in bulk electrolyte, finally bringing the balance between electroreduction kinetics and mass transfer process, which enables dendrite-free Zn deposition behavior. Concomitantly, the interfacial adsorbed Ala+ cations facilitate the electrochemical reduction of interfacial SO4 2- anions to form the inorganic-organic hybrid solid electrolyte interphase layer. The above domino effects immensely improve the utilization efficiency of Zn anodes and long-term stability, as demonstrated by the 12 times longer life of Zn||Zn cells (3650 h) and ultrahigh Coulombic efficiency (99.4 %).

3.
Oncologist ; 28(10): e859-e866, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37218076

RESUMO

BACKGROUND: Antibody-drug conjugates (ADCs) have been the preferred regimens for human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) after trastuzumab. Unfortunately, there is little data showing which ADCs should be chosen for those patients whose treatment with tyrosine kinase inhibitors (TKIs) failed. This study aims to analyze the efficacy and safety between novel anti-HER2 ADCs and trastuzumab emtansine (T-DM1) for those with TKIs failure. MATERIALS AND METHODS: HER2-positive MBC using ADCs from January 2013 to June 2022 were included, and all of them were treated with TKIs. The primary study endpoint was progression-free survival (PFS), and the secondary study endpoints were objective response rate (ORR), clinical benefit rate (CBR), and safety. RESULTS: A total of 144 patients with 73 patients in the novel anti-HER2 ADCs group and 71 patients in the T-DM1 group. In these novel ADCs, 30 patients received trastuzumab deruxtecan (T-Dxd), 43 patients receive other novel ADCs. The median PFS in the novel ADCs group and T-DM1 group were 7.0 months versus 4.0 months, respectively, and ORR was 54.8% versus 22.5%, CBR was 65.8% versus 47.9%, respectively. In subgroups analysis, the PFS were both significantly improved in patients receiving T-Dxd and other novel ADCs compared with T-DM1. The most common grades 3-4 adverse events in the novel anti-HER-2 ADCs group were neutropenia (20.5%) and thrombocytopenia (28.1%) in the T-DM1 group. CONCLUSIONS: In patients with HER2-positive MBC previously treated with TKIs, both T-Dxd and other novel anti-HER2 ADCs yielded statistically significant better PFS than T-DM1 did, with tolerable toxicities.


Assuntos
Antineoplásicos , Neoplasias da Mama , Imunoconjugados , Feminino , Humanos , Ado-Trastuzumab Emtansina/uso terapêutico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Imunoconjugados/uso terapêutico , Receptor ErbB-2/metabolismo , Trastuzumab/efeitos adversos , Trastuzumab/uso terapêutico , /uso terapêutico
4.
Mediators Inflamm ; 2023: 3706421, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37789884

RESUMO

Introduction: Osteoarthritis (OA) is the most common degenerative joint disorder. Prior studies revealed that activation of NLRP3 inflammasome could promote the activation and secretion of interleukin-1ß (IL-1ß), which has an adverse effect on the progression of OA. Betulinic acid (BA) is a compound extract of birch, whether it can protect against OA and the mechanisms involved are still unknown. Materials and Methods: In vivo experiments, using gait analysis, ELISA, micro-CT, and scanning electron microscopy (SEM), histological staining, immunohistological (IHC) and immunofluorescence (IF) staining, and atomic force microscopy (AFM) to assess OA progression after intraperitoneal injection of 5 and 15 mg/kg BA in an OA mouse model. In vitro experiments, caspase-1, IL-1ß, and the N-terminal fragment of gasdermin D (GSDMD-NT) were measured in bone marrow-derived macrophages (BMDMs) by using ELISA, western blot, and immunofluorescence staining. Results: We demonstrated that OA progression can be postponed with intraperitoneal injection of 5 and 15 mg/kg BA in an OA mouse model. Specifically, BA postponed DMM-induced cartilage deterioration, alleviated subchondral bone sclerosis, and relieved synovial inflammation. In vitro studies, the activated NLRP3 inflammasome produces mature IL-1ß by facilitating the cleavage of pro-IL-1ß, and BA could inhibit the activation of NLRP3 inflammasome in BMDMs. Conclusions: Taken together, our analyses revealed that BA attenuates OA via limiting NLRP3 inflammasome activation to decrease the IL-1ß maturation and secretion.


Assuntos
Inflamassomos , Osteoartrite , Animais , Camundongos , Ácido Betulínico , Modelos Animais de Doenças , Interleucina-1beta , Proteína 3 que Contém Domínio de Pirina da Família NLR , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia
5.
BMC Musculoskelet Disord ; 24(1): 605, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491231

RESUMO

BACKGROUND & OBJECTIVE: Little research was available to explore which surgical fixation was better between fixation of both clavicle and scapula and clavicle alone in management of floating shoulder injury. METHODS: Total 69 patients with floating shoulder injury receiving surgery from February 2005 to July 2020 participated in the study. 49 patients underwent fixation of the clavicle alone (Group C) while 20 patients underwent fixation of both clavicle and scapula (Group C + S). They were further divided into subgroups according to age: Group C1, Group C + S1 (age ≤ 55 years old) and Group C2, Group C + S2 (age>55 years old). The radiological parameter (glenopolar angle (GPA)) and clinical outcomes (Herscovici score, Constant-Murley shoulder outcome score (CSS score), and Visual Analogue Scale score (VAS score)) were collected and compared between these groups. The correlation between age and radiological parameter and clinical outcomes was calculated by the Spearman correlation analysis. RESULTS: All people were followed up for at least 1 year. The degree of change in GPA before and after surgery in Group C + S is significantly better than that in Group C. The Herscovici and CSS score in Group C + S2 were significantly higher than those in Group C2 at 1 month, 3 months and 1 year after surgery. However, no significant difference in Herscovici and CSS score was found at final follow-up (1 year after surgery) between Group C + S1 and Group C1. The VAS score in Group C + S2 at final follow-up was significantly lower than that in Group C2. No significant difference in VAS score at final follow-up was found between Group C + S1 and Group C1. In addition, the VAS score was negatively correlated with Herscovici and CSS score. No correlation was found between VAS score and GPA. CONCLUSIONS: Both types of surgical fixation are effective in management of floating shoulder injury. For young people with floating shoulder injury, both types of surgical fixation are equally effective. However, for older people with floating shoulder injury, fixation of both clavicle and scapula is better in prognosis than fixation of clavicle alone.


Assuntos
Fraturas Ósseas , Lesões do Ombro , Humanos , Idoso , Adolescente , Pessoa de Meia-Idade , Clavícula/diagnóstico por imagem , Clavícula/cirurgia , Clavícula/lesões , Estudos Retrospectivos , Fraturas Ósseas/cirurgia , Resultado do Tratamento , Escápula/diagnóstico por imagem , Escápula/cirurgia , Lesões do Ombro/cirurgia , Fixação Interna de Fraturas
6.
Small ; 18(16): e2200055, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35274442

RESUMO

Constructing ionic conductive hydrogels with diversified properties is crucial for portable zinc-ion hybrid supercapacitors (ZHSCs). Herein, a freeze-tolerant hydrogel electrolyte (AF PVA-CMC/Zn(CF3 SO3 )2 ) is developed by forming a semi-interpenetrating anti-freezing polyvinyl alcohol-carboxymethyl cellulose (AF PVA-CMC) network filled with the ethylene glycol (EG)-containing Zn(CF3 SO3 )2 aqueous solution. The semi-interpenetrating AF PVA-CMC/Zn(CF3 SO3 )2 possesses enhanced mechanical properties, realizes the uniform zinc deposition, and impedes the dendrite growth. Notably, the interaction between PVA and EG suppresses the ice crystal formation and prevents freezing at -20 °C. Due to these advantages, the designed hydrogel owns high ionic conductivity of 1.73/0.75 S m-1 at 20/-20 °C with excellent tensile/compression strength at 20 °C. Impressively, the flexible AF quasi-solid-state ZHSC employing the hydrogel electrolyte achieves a superior energy density at 20/-20 °C (87.9/60.7 Wh kg-1 ). It maintains nearly 84.8% of the initial capacity after 10 000 cycles and a low self-discharge rate (1.77 mV h-1 ) at 20 °C, together with great tolerance to corrosion. Moreover, this device demonstrates a stable electrochemical performance at -20 °C under deformation. The obtained results provide valuable insights for constructing durable hydrogel electrolytes in cold environments.

7.
Inorg Chem ; 61(9): 3866-3874, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35179879

RESUMO

Bimetallic metal-organic frameworks (MOFs) with an ultrathin configuration are compelling materials for developing high-performance energy storage devices on account of their unique structural merits. Herein, a hydrangea-like NiCo-MOF is well prepared using controllable solvothermal and cation-exchange processes, synchronously achieving bimetallic nodes and hierarchical ultrathin architecture. The structural superiority enables NiCo-MOF of expanded electrons' transfer pathways and multitudinous electrolytes' diffusion channels, resulting in a significant enhancement in pseudocapacitive performance. Coupling with the bimetallic nature and constructional advantages, NiCo-MOF shows superior gravimetric capacity (832.6 C g-1 at 1 A g-1) and electrochemical kinetics to those of monometallic Ni-MOF and Co-MOF. Importantly, the quasi-solid-state hybrid supercapacitor (HSC) based on the NiCo-MOF cathode and active carbon (AC) anode delivers a desirable energy density (45.3 Wh kg-1 at 847.8 W kg-1), a favorable power density (7160.0 W kg-1 at 23.3 Wh kg-1), a remarkable cyclability (82.4% capacity retention over 7000 cycles), and a capability of driving miniature electronics, exhibiting its potential in practical applications. This work presents an efficient design strategy to develop kinetics-favorable MOF materials for energy storage.

8.
J Pathol ; 255(1): 72-83, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34124783

RESUMO

Chordomas are primary bone tumors that arise in the cranial base, mobile spine, and sacrococcygeal region, affecting patients of all ages. Currently, there are no approved agents for chordoma patients. Here, we evaluated the anti-tumor efficacy of small molecule inhibitors that target oncogenic pathways in chordoma, as single agents and in combination, to identify novel therapeutic approaches with the greatest translational potential. A panel of small molecule compounds was screened in vivo against patient-derived xenograft (PDX) models of chordoma, and potentially synergistic combinations were further evaluated using chordoma cell lines and xenograft models. Among the tested agents, inhibitors of EGFR (BIBX 1382, erlotinib, and afatinib), c-MET (crizotinib), and mTOR (AZD8055) significantly inhibited tumor growth in vivo but did not induce tumor regression. Co-inhibition of EGFR and c-MET using erlotinib and crizotinib synergistically reduced cell viability in chordoma cell lines but did not result in enhanced in vivo activity. Co-inhibition of EGFR and mTOR pathways using afatinib and AZD8055 synergistically reduced cell viability in chordoma cell lines. Importantly, this dual inhibition completely suppressed tumor growth in vivo, showing improved tumor control. Together, these data demonstrate that individual inhibitors of EGFR, c-MET, and mTOR pathways suppress chordoma growth both in vitro and in vivo. mTOR inhibition increased the efficacy of EGFR inhibition on chordoma growth in several preclinical models. The insights gained from our study potentially provide a novel combination therapeutic strategy for patients with chordoma. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Afatinib/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cordoma/patologia , Morfolinas/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Inorg Chem ; 60(16): 12197-12205, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34324812

RESUMO

Fast-charged energy-storage technologies have become important nowadays as they are required by many applications, including automobiles. This inspires the exploitation of hybrid supercapacitors (HSCs) with the advantages of fast charge offered by the capacitor characters and high energy density from the property of battery technology. The challenges lay in the construction of advanced materials with high pseudocapacitive activity. Herein, a metal-organic framework derivative is utilized to address the problems. Specifically, polyhedral CoNi layered double hydroxide (CoNi-LDHx) cages assembled in the form of nanosheet arrays are prepared from ZIF-67 using a facile ion-exchange approach. Based on the control over the mass ratio of ZIF-67 to Ni salt, the optimal CoNi-LDH2 is attained. It exhibits ultrahigh capacities ranging from 1031.4 to 667.3 C g-1 under 1-25 A g-1, thanks to rich Faradaic active spots and the accelerated kinetics provided by the synergy between nanosheet arrays and the hollow structure. The CoNi-LDH2-based HSC with the gel electrolyte shares remarkable energy output of 49 Wh kg-1 and approving cyclability with almost no capacity decay after 12 000 cycles. This is an advancement vs many related studies and can arouse tremendous interests of researchers in solving the main problems of energy storage.

10.
Appl Opt ; 60(13): 3964-3970, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33983335

RESUMO

By analyzing Newton's rings, often encountered in interferometry, the parameters of spherical surfaces such as the rings' center and the curvature radius can be estimated. First, the classical convolutional neural networks, visual geometry group (VGG) network and U-Net, are applied to parameter estimation of Newton's rings. After these models are trained, the rings' center and curvature radius can be obtained simultaneously. Compared with previous analysis methods of Newton's rings, it is shown that the proposed method has higher precision, better immunity to noise, and lower time consumption. For a Newton's rings pattern of ${{640}} \times {{480}}$ pixels comprising ${-}{{5}}\;{\rm{dB}}$ Gaussian noise or 60% salt-and-pepper noise, the parameters can be estimated by the VGG model in 0.01 s, the error of the rings' center is less than one pixel, and the error of curvature radius is lower than 0.5%.

11.
World J Surg ; 44(10): 3207-3211, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32766957

RESUMO

BACKGROUND: The COVID-19 pandemic has resulted in a significant decrease in the number of elective cancer operations performed. Cancer patients are felt to be a high-risk group for COVID-19, and therefore, concerns have been raised regarding the safety of operating during this time; however, the potential risk of cancer progression if untreated must also be considered. The aim of this study was therefore to identify the incidence of COVID-19 post-operatively in patients undergoing elective cancer surgery of all types. METHODS: Data were collected on all patients who had an elective therapeutic cancer operation in a single large district general hospital, where standard COVID-19 precautions were in place, between 01/02/2020 and 27/4/2020, Follow-up was for a minimum of 2 weeks post-discharge. The primary outcome was the incidence of COVID-19 during the follow-up period. RESULTS: A total of 621 elective cancer surgeries, from a range of specialities, were performed during the study period, with 55% (n = 341) being done as day cases. None of the patients were positive for COVID-19 post-operatively using reverse transcriptase polymerase chain reaction testing. CONCLUSIONS: The risk of COVID-19 following elective cancer surgery in this group of high-risk patients appears to be minimal in this study. With further precautions being introduced to reduce the risk of transmission of COVID-19, an increase in the rate of elective cancer surgery should be a current priority for all hospitals where possible.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Procedimentos Cirúrgicos Eletivos , Neoplasias/cirurgia , Segurança do Paciente , Pneumonia Viral/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/etiologia , Infecções por Coronavirus/prevenção & controle , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico , Pneumonia Viral/etiologia , Pneumonia Viral/prevenção & controle , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Reino Unido
12.
World J Surg Oncol ; 18(1): 315, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261630

RESUMO

BACKGROUND: Increasing evidence suggested that microRNA and kinesin superfamily proteins play an essential role in ovarian cancer. The association between KIF4A and ovarian cancer (OC) was investigated in this study. METHODS: We performed bioinformatics analysis in the GEO database to screen out the differentially expressed miRNAs (DEmiRNAs) associated with ovarian cancer prognosis. Upstream targeting prediction for KIF4A was acquired by using the mirDIP database. The potential regulatory factor miR-29c-3p for KIF4A was obtained from the intersection of the above all miRNAs. The prognosis of KIF4A and target-miRNA in OC was obtained in the subsequent analysis. qRT-PCR and Western blot detected KIF4A expression level in IOSE80 (human normal ovarian epithelial cell line). In the meantime, the gene expression level was detected in A2780, HO-8910PM, COC1, and SKOV3 cell lines (human ovarian carcinoma cell line). MTT and colony formation assays were used to detect cell proliferation of SKOV3 cell line. The following assays detected cell migration through the use of transwell and wound heal assays. Targeted binding relationship between KIF4A and miRNA was detected by using the dual-luciferase reporter assay. RESULTS: Both high expression of KIF4A and lower expression of miR-29c-3p could be used as biomarkers indicating poor prognosis in OC patients. Cellular function tests confirmed that when KIF4A was silenced, it inhibited the proliferation and migration of OC cells. In addition, 3'-UTR of KIF4A had a direct binding site with miR-29c-3p, which indicated that the expression of KIF4A could be regulated by miR-29c-3p. In subsequent assays, the proliferation and migration of OC cells were inhibited by the overexpression of miR-29c-3p. At the same time, rescue experiments also confirmed that the promotion of KIF4A could be reversed by miR-29c-3p. CONCLUSION: In a word, our data revealed a new mechanism for the role of KIF4A in the occurrence and development of OC.


Assuntos
Cinesinas , MicroRNAs , Neoplasias Ovarianas , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Cinesinas/genética , MicroRNAs/genética , Neoplasias Ovarianas/genética , Prognóstico
13.
ACS Appl Mater Interfaces ; 16(19): 25181-25193, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38698676

RESUMO

Supermolecular hydrogel ionic skin (i-skin) linked with smartphones has attracted widespread attention in physiological activity detection due to its good stability in complex scenarios. However, the low ionic conductivity, inferior mechanical properties, poor contact adhesion, and insufficient freeze resistance of most used hydrogels limit their practical application in flexible electronics. Herein, a novel multifunctional poly(vinyl alcohol)-based conductive organohydrogel (PCEL5.0%) with a supermolecular structure was constructed by innovatively employing sodium carboxymethyl cellulose (CMC-Na) as reinforcement material, ethylene glycol as antifreeze, and lithium chloride as a water retaining agent. Thanks to the synergistic effect of these components, the PCEL5.0% organohydrogel shows excellent performance in terms of ionic conductivity (1.61 S m-1), mechanical properties (tensile strength of 70.38 kPa and elongation at break of 537.84%), interfacial adhesion (1.06 kPa to pig skin), frost resistance (-50.4 °C), water retention (67.1% at 22% relative humidity), and remoldability. The resultant PCEL5.0%-based i-skin delivers satisfactory sensitivity (GF = 1.38) with fast response (348 ms) and high precision under different deformations and low temperature (-25 °C). Significantly, the wireless sensor system based on the PCEL5.0% organohydrogel i-skin can transmit signals from physiological activities and sign language to a smartphone by Bluetooth technology and dynamically displays the status of these movements. The organohydrogel i-skin shows great potential in diverse fields of physiological activity detection, human-computer interaction, and rehabilitation medicine.


Assuntos
Hidrogéis , Hidrogéis/química , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Animais , Tecnologia sem Fio , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Humanos , Álcool de Polivinil/química , Suínos , Smartphone , Pele/química , Carboximetilcelulose Sódica/química
14.
Carbohydr Polym ; 342: 122425, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39048208

RESUMO

The development of irreversible on/off switching materials is a potential strategy for unidirectional capture and encapsulation of pollutants, preventing the pollutant leakage problem resulting from the reversible dissolution of flocculants. Herein, a thermo-irreversible on/off switch starch (TISS) is prepared through modifying starch by etherification grafting glycidyl phenyl ether and 2,4-bis(dimethylamino)-6-chloro-[1,3,5]-triazine. It breaks the dissolution/precipitation dynamic equilibrium across heating-cooling cycles by thermal-induced irreversible coil-to-globule self-assembly of polymer chains, resulting in a 50-fold decrease in polymer solubility. Particularly, TISS shows a superior double-locking effect on pollutants and flocculants through its unique irreversible conformation memory capability, leading to a high-quality reuse water. 99.9 % of reactive brilliant red dye and 97.9 % of TISS remain fixed within sludge flocs even after prolonged immersion in cold water at 24 °C for 60 days. Furthermore, direct recycling and reuse of dye-bath energy can be realized through the isothermal flocculation and dyeing method, showing a 75 % decrease in energy consumption after three cycles compared to traditional dyeing techniques. This work presents a novel approach to constructing an irreversible pollutant delivery system using thermo-irreversible on/off switch starch, addressing the problems of high energy dissipation and water quality fluctuations during wastewater treatment.

15.
Neuro Oncol ; 26(4): 684-700, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38070488

RESUMO

BACKGROUND: Dysregulation of cholesterol metabolism is a significant characteristic of glioma, yet the underlying mechanisms are largely unknown. N6-methyladenosine (m6A) modification has been implicated in promoting tumor development and progression. The aim of this study was to determine the key m6A regulatory proteins involved in the progression of glioma, which is potentially associated with the reprogramming of cholesterol homeostasis. METHODS: Bioinformatics analysis was performed to determine the association of m6A modification with glioma malignancy from The Cancer Genome Atlas and Genotype-Tissue Expression datasets. Glioma stem cell (GSC) self-renewal was determined by tumor sphere formation and bioluminescence image assay. RNA sequencing and lipidomic analysis were performed for cholesterol homeostasis analysis. RNA immunoprecipitation and luciferase reporter assay were performed to determine hnRNPA2B1-dependent regulation of sterol regulatory element-binding protein 2 (SREBP2) and low-density lipoprotein receptor (LDLR) mRNA. The methylation status of hnRNPA2B1 promoter was determined by bioinformatic analysis and methylation-specific PCR assay. RESULTS: Among the m6A-regulatory proteins, hnRNPA2B1 was demonstrated the most important independent prognostic risk factor for glioma. hnRNPA2B1 ablation exhibited a significant tumor-suppressive effect on glioma cell proliferation, GSC self-renewal and tumorigenesis. hnRNPA2B1 triggers de novo cholesterol synthesis by inducing HMGCR through the stabilization of SREBP2 mRNA. m6A modification of SREBP2 or LDLR mRNA is required for hnRNPA2B1-mediated mRNA stability. The hypomethylation of cg21815882 site on hnRNPA2B1 promoter confers elevated expression of hnRNPA2B1 in glioma tissues. The combination of targeting hnRNPA2B1 and cholesterol metabolism exhibited remarkable antitumor effects, suggesting valuable clinical implications for glioma treatment. CONCLUSIONS: hnRNPA2B1 facilitates cholesterol uptake and de novo synthesis, thereby contributing to glioma stemness and malignancy.


Assuntos
Colesterol , Glioma , Humanos , Colesterol/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Glioma/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homeostase
16.
J Colloid Interface Sci ; 658: 506-517, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38128194

RESUMO

The lack of cathode materials with satisfactory Zn2+ storage capability substantially hinders the realization of high-performance aqueous zinc-ion hybrid capacitors (ZHCs). Herein, we propose a facile KMnO4 template-assisted KOH activation strategy to prepare a novel oxygen-enriched hierarchically porous carbon (HPC-1-4). This strategy efficiently converts coal tar pitch (CTP) into a well-tuned carbon material with a large specific surface area of 3019 m2 g-1 and a high oxygen content of 9.20 at%, which is conducive to providing rich active sites, rapid charge transport, and appreciable pseudocapacitance for Zn-ion storage. Thus, the as-fabricated HPC-1-4-based aqueous ZHC exhibits prominent performance, including a high gravimetric capacity (206.7 mAh g-1 at 0.25 A g-1), a remarkable energy density (153.4 Wh kg-1 at 184.2 W kg-1), and an impressive power output (15240 W kg-1 at 63.5 Wh kg-1). In-depth ex-situ characterizations indicate that the excellent electrochemical properties of ZHCs are due to the synergistic effect of the Zn2+ adsorption mechanism and reversible chemisorption. In addition, the assembled quasi-solid-state device demonstrates excellent electrochemical stability of up to 100% capacity retention over 50000 cycles, accompanied with a desirable energy density of 115.6 Wh kg-1. The facile preparation method of converting CTP into carbonaceous functional materials has advanced the development of efficient and eco-friendly energy storage technologies.

17.
Nanotechnology ; 24(27): 275602, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23743520

RESUMO

We have demonstrated an environmentally friendly in situ assembly method for the preparation of novel three-dimensional TiO2/graphene oxide (TiO2/GO) nanostructures with favorable flower-shaped architectures. Very little information on such a morphology of TiO2/GO nanostructures is available in the literature. The as-synthesized sample was characterized by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption measurements and Raman spectroscopy. Also the TiO2/GO composites exhibited enhanced photocatalytic properties.


Assuntos
Grafite/química , Nanopartículas/química , Óxidos/química , Titânio/química , Catálise , Química Verde , Nanopartículas/ultraestrutura
18.
Small Methods ; 7(2): e2201398, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36564360

RESUMO

Rechargeable aqueous zinc-ion hybrid capacitors (ZHCs) have aroused unprecedented attention because of their high safety, cost effectiveness, and environmental compatibility. However, the intractable issues of dendrite growth and side reactions at the electrode-electrolyte interface deteriorate durability and reversibility of Zn anodes, deeply encumbering the large-scale application of ZHCs. Concerning these obstacles, a negatively charged carboxylated chitosan-intensified hydrogel electrolyte (CGPPHE) with cross-linked networks is reported to stabilize Zn anodes. Beyond possessing good mechanical characteristics, the CGPPHE with polar groups can reduce the desolvation energy barrier of hydrated Zn2+ , constrain the 2D Zn2+ diffusion, and uniformize electric field and Zn2+ flux distributions, assuring dendrite-free Zn deposition with high plating-stripping efficiency. Concurrently, the hydrophilic CGPPHE alleviates harmful hydrogen evolution and corrosion by abating water activity. Accordingly, Zn|CGPPHE|Zn and Zn|CGPPHE|Cu cells exhibit an extended life exceeding 350 h (1600 mAh cm-2 cumulative capacity under 20 mA cm-2 ) and a high average coulombic efficiency of 98.2%, respectively. The resultant flexible ZHCs with CGPPHE and template-regulated carbon cathode present perfect properties in capacity retention (97.7% over 10 000 cycles), energy density (91.8 Wh kg-1 ), and good mechanical adaptability. This study provides insight into developing novel hydrogel electrolytes toward highly rechargeable and stable ZHCs.

19.
Adv Sci (Weinh) ; 10(8): e2205794, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36670056

RESUMO

Aqueous zinc-manganese (Zn-Mn) batteries have promising potential in large-scale energy storage applications since they are highly safe, environment-friendly, and low-cost. However, the practicality of Mn-based materials is plagued by their structural collapse and uncertain energy storage mechanism upon cycling. Herein, this work designs an amorphous manganese borate (a-MnBOx ) material via disordered coordination to alleviate the above issues and improve the electrochemical performance of Zn-Mn batteries. The unique physicochemical characteristic of a-MnBOx enables the inner a-MnBOx to serve as a robust framework in the initial energy storage process. Additionally, the amorphous manganese dioxide, amorphous Znx MnO(OH)2 , and Zn4 SO4 (OH)6 ·4H2 O active components form on the surface of a-MnBOx during the charge/discharge process. The detailed in situ/ex situ characterization demonstrates that the heterostructure of the inner a-MnBOx and surface multicomponent phases endows two energy storage modes (Zn2+ /H+ intercalation/deintercalation process and reversible conversion mechanism between the Znx MnO(OH)2 and Zn4 SO4 (OH)6 ·4H2 O) phases). Therefore, the obtained Zn//a-MnBOx battery exhibits a high specific capacity of 360.4 mAh g-1 , a high energy density of 484.2 Wh kg-1 , and impressive cycling stability (97.0% capacity retention after 10 000 cycles). This finding on a-MnBOx with a dual-energy storage mechanism provides new opportunities for developing high-performance aqueous Zn-Mn batteries.

20.
Nat Commun ; 14(1): 7414, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37973849

RESUMO

Supported metal catalysts often suffer from rapid degradation under harsh conditions due to material failure and weak metal-support interaction. Here we propose using reductive hydrogenated borophene to in-situ synthesize Pt/B/C catalysts with small sizes (~2.5 nm), high-density dispersion (up to 80 wt%Pt), and promising stability, originating from forming Pt-B bond which are theoretically ~5× stronger than Pt-C. Based on the Pt/B/C module, a series (~18 kinds) of carbon supported binary, ternary, quaternary, and quinary Pt intermetallic compound nanocatalysts with sub-4 nm size are synthesized. Thanks to the stable intermetallics and strong metal-support interaction, annealing at 1000 °C does not cause those nanoparticles sintering. They also show much improved activity and stability in electrocatalytic oxygen reduction reaction. Therefore, by introducing the boron chemistry, the hydrogenated borophene derived multielement catalysts enable the synergy of small size, high loading, stable anchoring, and flexible compositions, thus demonstrating high versatility toward efficient and durable catalysis.

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