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The inflammatory microenvironment is a central driver of tumor metastasis, intimately associated with the promotion of epithelial-mesenchymal transition (EMT) and immune suppression. Here, transferrin-modified carprofen platinum(IV) nanoparticles Tf-NPs@CPF2-Pt(IV) with promising antiproliferative and antimetastatic properties were developed, which activated by inhibiting inflammation, suppressing EMT, and activating immune responses besides causing DNA injury. The nanoparticles released the active ingredient CPF2-Pt(IV) in a sustained manner and offered enhanced pharmacokinetic properties compared to free CPF2-Pt(IV) in vivo. Additionally, they possessed satisfactory tumor targeting effects via the transferrin motif. Serious DNA damage was induced with the upregulation of γ-H2AX and P53, and the mitochondria-mediated apoptotic pathway Bcl-2/Bax/caspase3 was initiated. Inflammation was alleviated by inhibiting COX-2 and MMP9 and decreasing inflammatory cytokines TNF-α and IL-6. Subsequently, the EMT was reversed by inhibiting the Wnt/ß-catenin pathway. Furthermore, the antitumor immunity was provoked by blocking the immune checkpoint PD-L1 and increasing CD3+ and CD8+ T lymphocytes in tumors.
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Protective autophagy is a promising target for antitumor drug exploration. A hydroxychloroquine (HCQ) platinum(IV) complex with autophagy suppressing potency was developed, which displayed potent antitumor activities with a TGI rate of 44.2% against 4T1 tumors in vivo and exhibited a rather lower toxicity than cisplatin. Notably, it exhibited satisfactory antimetastatic activities toward lung pulmonary metastasis models with an inhibition rate of 49.6% and was obviously more potent than CDDP, which has an inhibition rate of 21.6%. Mechanism detection revealed that it caused serious DNA damage and upregulated the expression of γ-H2AX and p53. More importantly, the incorporation of an autophagy inhibitor HCQ endowed the platinum(IV) complex with potent autophagy impairing properties by perturbing the lysosomal function in tumor cells, which promoted apoptosis synergistically with DNA injury. Then, the impaired autophagy further led to the suppression of hypoxia and inflammation in the tumor microenvironment by downregulating ERK1/2, HIF-1α, iNOS, caspase1 and COX-2. Adaptive immune response was improved by inhibiting the immune checkpoint PD-L1 and further increasing CD4+ and CD8+ T cells in tumors. Then, tumor metastasis was effectively inhibited by restraining angiogenesis through inhibiting VEGFA, MMP-9, and CD34.
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Antineoplásicos , Autofagia , Hidroxicloroquina , Microambiente Tumoral , Hidroxicloroquina/farmacologia , Hidroxicloroquina/química , Autofagia/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Camundongos , Humanos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Platina/química , Platina/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Camundongos Endogâmicos BALB C , Ensaios de Seleção de Medicamentos Antitumorais , Apoptose/efeitos dos fármacosRESUMO
Mitophagy is an important target for antitumor drugs development. A series of ciclopirox (CPX) platinum(IV) hybrids targeting PTEN induced putative kinase 1 (PINK1)/Parkin mediated mitophagy were designed and prepared as antitumor agents. The dual CPX platinum(IV) complex with cisplatin core was screened out as a candidate, which displayed promising antitumor activities both in vitro and in vivo. Mechanistically, it caused serious DNA damage in tumor cells. Then, remarkable mitochondrial damage was induced accompanied by the mitochondrial membrane depolarization and reactive oxygen species generation, which further promoted apoptosis through the Bcl-2/Bax/Caspase3 pathway. Furthermore, mitophagy was ignited via the PINK1/Parkin/P62/LC3 axis, and exhibited positive influence on promoting the apoptosis of tumor cells. The antitumor immunity was boosted by the block of immune check point programmed cell death ligand-1 (PD-L1), which further increased the density of T cells in tumors. Subsequently, the metastasis of tumor cells was inhibited by inhibiting angiogenesis in tumors.
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Antineoplásicos , Ciclopirox , Mitofagia , Ciclopirox/farmacologia , Humanos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Camundongos , Mitofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Platina/química , Platina/farmacologia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/imunologia , Neoplasias/metabolismo , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismoRESUMO
Epithelial-mesenchymal transition (EMT) is a critical process for cancer progression, which is crucial in inhibiting the immunity in tumors and further boosting tumor metastasis. The suppression of EMT represents a promising strategy for inhibiting metastatic tumors. Herein, a series of new canadine platinum(IV) conjugates with potent antiproliferative and antimetastatic activities were developed, which activated by suppressing EMT and provoking immune response in tumors besides causing DNA injury. The complexes could covalently conjugate to DNA and induce mitochondria-mediated apoptosis via Bcl-2/Bax/caspase3 signaling. The EMT process was remarkably inhibited by suppressing the Wnt/ß-catenin pathway, reversing the inflammatory tumor microenvironment, and inhibiting the HIF-1α pathway, which further resulted in the inhibited angiogenesis in tumors. Moreover, the antitumor immunity was elevated by blocking immune checkpoints PD-L1 and CD47 accompanied by the improvement of CD3+ and CD8+ T lymphocytes and the macrophage polarization from M2- toward M1-type simultaneously in tumors.
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Antineoplásicos , Proliferação de Células , Transição Epitelial-Mesenquimal , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Animais , Camundongos , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/química , Microambiente Tumoral/efeitos dos fármacos , Metástase Neoplásica , Feminino , Camundongos Endogâmicos BALB C , Ensaios de Seleção de Medicamentos AntitumoraisRESUMO
Fungal infections maintain a close relation with the body's immune function. In this study, three series of benzazole compounds were designed as dual-target (PD-L1/CYP51) inhibitors using the skeleton splicing approach; their molecular structures were synthesized and evaluated accordingly. Among them, the compounds 9a-2, 12a-2, and 12b-1 exhibited potent antifungal activity and dual-target inhibition ability. Especially, the compound 12a-2 simultaneously exerted excellent bifunctional effects of fungal inhibition and immune activation. Moreover, a layered double hydroxide (LDH) carrier was also successfully constructed based on an infection microenvironment to improve the bioavailability and the targeting of compound 12a-2. This significantly accelerated the recovery process of deep and shallow fungal infections. In conclusion, this study expanded the development horizon of antifungal drugs and provided a novel drug delivery route for treating fungal infections.
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Antifúngicos , Desenho de Fármacos , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Humanos , Relação Estrutura-Atividade , Animais , Camundongos , Portadores de Fármacos/química , Estrutura Molecular , Candida albicans/efeitos dos fármacos , Inibidores de 14-alfa Desmetilase/farmacologia , Inibidores de 14-alfa Desmetilase/síntese química , Inibidores de 14-alfa Desmetilase/química , Simulação de Acoplamento MolecularRESUMO
Faced with increasingly serious fungal infections and drug resistance issues, three different series of novel dual-target (programmed death ligand 1/14 α-demethylase) compounds were constructed through the fragment combination pathway in the study. Their chemical structures were synthesized, characterized, and evaluated. Among them, preferred compounds 10c-1, 17b-1, and 18b-2 could efficiently exert their antifungal and antidrug-resistant fungal ability through blocking ergosterol biosynthesis, inducing the upregulation of reactive oxygen species level, and triggering apoptosis. Especially, compound 18b-2 exhibited the synergistic function of fungal inhibition and immune activation. Moreover, the covalent organic framework carrier was also generated based on the acidic microenvironment of fungal infection to improve the bioavailability and targeting of preferred compounds; this finally accelerated the body's recovery rate.
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Antifúngicos , Antifúngicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Humanos , Animais , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Inibidores de 14-alfa Desmetilase/farmacologia , Inibidores de 14-alfa Desmetilase/química , Inibidores de 14-alfa Desmetilase/síntese química , Micoses/tratamento farmacológico , Camundongos , Candida albicans/efeitos dos fármacos , Ergosterol/metabolismo , Estrutura MolecularRESUMO
To develop aryloxyphenoxypropionate herbicides with a novel structure and improved activity, a total of 39 aryloxyphenoxypropionate/amide derivatives containing quinazolinone moiety were synthesized and further bioevaluated. The bioassay results in the greenhouse showed that most of the target compounds had good herbicidal activity under postemergence conditions, of which, QPP-I-6 displayed excellent herbicidal activity against Echinochloa crusgalli, Digitaria sanguinalis, Spartina alterniflora, Eleusine indica, and Pennisetum alopecuroides with inhibition rates >90% at a dosage of 187.5 g ha-1. More importantly, QPP-I-6 displayed higher crop safety to Gossypium hirsutum, Glycine max, and Arachis hypogaea than the commercial herbicide quizalofop-p-ethyl. Studying the molecular mode of action by phenotypic observation, membrane permeability evaluation, transcriptomic analysis, and in vivo ACCase activity evaluation reveals that QPP-I-6 is a novel ACCase inhibitor. The present work demonstrates that QPP-I-6 can serve as a lead compound for further developing novel ACCase-inhibiting herbicides.
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Three-dimensional high-resolution anorectal manometry (3DHRAM) is a new technique that can explore anorectal disorders and provide interesting topographic data for the diagnosis of pelvic floor disorders such as paradoxical puborectalis syndrome (PPS). Our object was to evaluate whether 3DHRAM can reliably diagnose PPS already diagnosed with X-ray defaecography, which is considered to be the gold standard. All patients being tested in our department for dyschezia by 3D-HRAM and X-ray defecography were eligible for the study. The 3DHRAM results were compared with X-ray defecography. The sensitivity, specificity, and positive and negative predictive values were calculated for various 3DHRAM criteria to propose a diagnostic strategy for PPS. Twenty-three patients presented with PPS on X-ray defaecography. On 3DHRAM, according to our diagnostic strategy, the kappa value was 0.706, with a positive predictive value of 71.88% [95% CI, 53.02-85.60], a specificity of 80.43% [95% CI, 65.62-90.13], a sensibility of 95.83% [95% CI, 76.98-99.78], and area under curve value was 0.922. In this study, 3DHRAM was used to diagnose PPS with the same degree of reliability as X-ray defaecography, and we confirmed its use in the diagnosis of pelvic floor disorders. Further studies will be necessary to define classifications for these new anatomic data from 3DHRAM.
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Canal Anal , Distúrbios do Assoalho Pélvico , Feminino , Humanos , Projetos Piloto , Canal Anal/diagnóstico por imagem , Raios X , Distúrbios do Assoalho Pélvico/diagnóstico por imagem , Reprodutibilidade dos Testes , Manometria/métodos , Constipação Intestinal/diagnóstico por imagem , Defecografia/métodosRESUMO
This study established a method for rapid quantification of terpene lactone, bilobalide, ginkgolide C, ginkgolide A and ginkgolide B in the chromatographic process of Ginkgo Folium based on near infrared spectroscopy(NIRS). The effects of competitive adaptive reweighting sampling(CARS), random frog(RF), and synergy interval partial least squares(siPLS) on the performance of partial least squares regression(PLSR) model were compared to the reference values measured by HPLC. Among them, the correlation coefficients of prediction(Rp) of validation sets of terpene lactone, bilobalide, and ginkgolide C were all higher than 0.98, and the relative standard errors of prediction(RSEPs) were 5.87%, 6.90% and 6.63%, respectively. Aiming at ginkgolide A and ginkgolide B with relatively low content, the genetic algorithm joint extreme learning machine(GA-ELM) was used to establish the optimized quantitative analysis model. Compared with CARS-PLSR model, the CARS-GA-ELM models of ginkgolide A and ginkgolide B exhibited a reduction in RSEP from 15.65% to 8.52% and from 21.28% to 10.84%, respectively, which met the needs of quantitative ana-lysis. It has been proved that NIRS can be used for the rapid detection of various lactone components in the chromatographic process of Ginkgo Folium.
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Ginkgo biloba , Espectroscopia de Luz Próxima ao Infravermelho , Cromatografia Líquida de Alta Pressão , Lactonas/análise , Análise dos Mínimos Quadrados , Espectroscopia de Luz Próxima ao Infravermelho/métodosRESUMO
BACKGROUND: Exercise tolerance and lung function can be improved by pulmonary rehabilitation. As a result, it may lower thoracic surgery intensive care unit (ICU) patients' postoperative problems and death. Enhanced recovery after surgery has advanced significantly in the perioperative care of thoracic surgery ICU patients in recent years, and it now plays an essential role in improving ICU patients' postoperative prognosis. Appropriate tailored rehabilitation nursing intervention is required to promote the postoperative recovery of respiratory function in thoracic surgery ICU patients. This study aims to look at the influence of tailored rehabilitation nurse intervention on postoperative respiratory function recovery in thoracic surgery ICU patients. METHODS: To find relevant papers, a comprehensive search of electronic databases will be conducted, including three English databases (PubMed, EMBASE, and the Cochrane Library) and two Chinese databases (Chinese National Knowledge Infrastructure and WanFang). Only research that has been published in either English or Chinese will be considered. The retrieval period will run from November 2021 to November 2021. We will look at randomized controlled trials (RCTs) studies that looked at the effect of a customized rehabilitation nursing intervention on the recovery of respiratory function in thoracic surgery ICU patients after surgery. Two writers will review the literature, retrieve study data, and assess the included studies' quality. Any disagreements will be settled via consensus. RevMan 5.3 will be used to do the meta-analysis. RESULTS: This research will offer high-quality data on the influence of customized rehabilitation nurse intervention on postoperative respiratory function recovery in thoracic surgery ICU patients. CONCLUSION: This study will look at whether a targeted rehabilitation nurse intervention might help thoracic surgery ICU patients recover their respiratory function more quickly after surgery. ETHICS AND DISSEMINATION: There will be no need for ethical approval. REGISTRATION NUMBER: December 12, 2021.osf.io/9rdu2/ (https://osf.io/9rdu2/).
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Assistência ao Convalescente , Cuidados de Enfermagem/métodos , Assistência Centrada no Paciente , Cuidados Pós-Operatórios/métodos , Reabilitação , Procedimentos Cirúrgicos Operatórios/reabilitação , Cirurgia Torácica , Humanos , Unidades de Terapia Intensiva , Metanálise como Assunto , Projetos de Pesquisa , Revisões Sistemáticas como Assunto , Resultado do TratamentoRESUMO
BACKGROUND: Cervical spondylotic radiculopathy (CSR) is one of the most common types of cervical spondylosis, and its treatments are mainly for relieving radicular pain and improving dysfunction. The existing randomized controlled trials (RCTs) suggest that fire needle may be a potential therapy in the treatment of CSR, but there is no evidence-based medical evidence to date. Therefore, this study will systematically evaluate the efficacy and safety of fire needle in the treatment of CSR. METHODS: We will search for 7 electronic databases (PubMed, EMBASE, Cochrane library, China National Knowledge Infrastructure, Chinese Scientific Journals Database, Sinomed, and Wanfang Database) and 2 trial registration platforms (ClinicalTrials.gov and Chinese Clinic Trials.gov) to collect eligible studies. The RCTs related to fire needle for CSR and published up to June 30, 2021 will be included, regardless of language. We will consider the visual analogue scale as the primary outcome and the secondary outcome will include cervical range of motion, assessment of muscle strength, neck disability index, the MOS item short from health survey, activities of daily living, total efficiency, and adverse reactions. We will use the standard proposed in Cochrane Handbook 5.1.0 to assess the quality and bias risk of every RCT, and all analyses will be conducted through RevMan software V5.3 (Copenhagen: Nordic Cochrane Center, Cochrane, Collaborative Organization, 2014). RESULTS: This systematic review and meta-analysis will provide a convincing synthesis of existing evidences on the efficacy and safety of fire needle for CSR, and the results will be submitted to a peer-reviewed journal for publication. CONCLUSION: The results of this study will provide high-quality evidence of fire needle in the treatment of CSR for clinical decision-making. INPLASY REGISTRATION NUMBER: INPLASY202170041.
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Terapia por Acupuntura , Radiculopatia , Espondilose/complicações , Terapia por Acupuntura/efeitos adversos , Terapia por Acupuntura/instrumentação , Terapia por Acupuntura/métodos , Humanos , Metanálise como Assunto , Radiculopatia/etiologia , Radiculopatia/terapia , Projetos de Pesquisa , Revisões Sistemáticas como Assunto , Resultado do TratamentoRESUMO
In the past few years, continuous manufacturing(CM) has been put forward by the FDA. Pharmaceutical enterprises are encouraged to promote the implementation of CM, which has become a hot research direction of pharmaceutical technology. In February 2019, the FDA issued a draft guideline for the implementation of CM, which greatly promoted the development of CM and provided reference for continuous manufacturing of traditional Chinese medicine(TCM). The production process of TCM is a complex system. With the innovation of production equipment and the promotion of automation and informatization of TCM production, the exis-ting policies, regulations and traditional production control capacity are difficult to meet the market demand for high-quality TCM pro-ducts. In this paper, we reviewed the new technologies and methods of quality control in accordance with the characteristics of TCM production by referring to modern manufacturing technology, information technology and quality control technology. Based on the "QbD" theory and "PAT" technology, process knowledge system(PKS), an advanced control strategy, was proposed to provide a reference for the implementation of CM in TCM production.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Comércio , Controle de Qualidade , Tecnologia FarmacêuticaRESUMO
RESULTS: Results showed the overall structure of gut microbiome has no significant difference between experimental and control groups. In the genus level, the abundance of Pseudobutyrivibrio and Ruminiclostridium is higher in the experiment group than in the control, whereas that of Fusicatenibacter is less. The 16S KEGG function prediction suggested that Parkinson disease, retinol metabolism, and arachidonic acid metabolism could explain the biological function of different gut microbiome. Furthermore, cytokines in the serum showed a correlation with the abundance of Pseudobutyrivibrio in CFC. CONCLUSION: AMT could change the composition of gut microbiome which is associated with cytokines in CFC patients.
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Singlet oxygen (1O2), as an important active reagent, has found wide applications in photodynamic therapy (PDT), synthetic chemistry, and materials science. Organic conjugated aromatics serving as hosts to capture and release singlet oxygen have been systematically investigated over the last decades. Herein, we present a [6 + 6] organoplatinum(II) metallacycle by using â¼180° dipyridylanthracene donor and â¼120° Pt(II) acceptor as the building blocks, which enables the capture and release of singlet oxygen with relatively high photooxygenation and thermolysis rate constants. The photooxygenation of the metallacycle to the corresponding endoperoxide was performed by sensitized irradiation, and the resulting endoperoxide is stable at room temperature and can be stored under ambient condition over months. Upon simple heating of the neat endoperoxide under inert atmosphere at 120 °C for 4 h, the resulting endoperoxide can be reconverted to the corresponding parent form and singlet oxygen. The photooxygenation and thermolysis products were characterized by NMR spectroscopy and electrospray ionization time-of-flight mass spectrometric analysis. Density functional theory calculations were conducted in order to reveal the frontier molecular orbital interactions and reactivity. This work provides a new material platform for singlet oxygen related promising applications.
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Compostos Organometálicos/química , Compostos de Platina/química , Oxigênio Singlete/química , Hidrocarbonetos Policíclicos Aromáticos/química , Análise Espectral/métodosRESUMO
In this work, we present the formation of two open-ended hexagonal-prism tubular macrocycles by the [6 + 12] self-assembly of the symmetric â¼120° organic ligand donor with â¼90° Pt(II) acceptor in a 1:2 ratio. The assembled structures were characterized by multinuclear NMR (1H NMR, 31P{1H} NMR, and 1H-1H COSY NMR), electrospray ionization mass spectrometry (ESI-TOF-MS), traveling wave ion mobility-mass spectrometry (TWIM-MS), and transmission electron microscopy. Molecular modeling was further conducted to get insight into their structured characteristics. We also examined their photophysical properties.
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Duplication of MECP2 (Methyl-CpG-binding protein 2) causes severe mental illness called MECP2 duplication syndrome (MDS), yet the underlying mechanism remains elusive. Here we show, in Tg(MECP2) transgenic mouse brain or cultured neural progenitor cells (NPCs), that elevated MeCP2 expression promotes NPC differentiation into neurons. Ectopic expression of MeCP2 inhibits ADAM10 and thus the NOTCH pathway during NPC differentiation. In human cells, this downregulation on ADAM10 was mediated by miRNA-197, which is upregulated by MeCP2. Surprisingly, miR-197 binds to the ADAM10 3'-UTR via its 3' side, not the canonical seed sequence on the 5' side. In mouse cells, a noncoding RNA Gm28836 is used to replace the function of miR-197 between MeCP2 and ADAM10. Similar to MeCP2, overexpressing miR-197 also promotes NPCs differentiation into neurons. Interestingly, three rare missense mutations (H371R, E394K, and G428S) in MECP2, which we identified in a Han Chinese autism spectrum disorders (ASD) cohort showed loss-of-function effects in NPC differentiation assay. These mutations cannot upregulate miR-197. Overexpressing miR-197 together with these MeCP2 mutations could rescue the downregulation on ADAM10. Not only the inhibitor of miR-197 could reverse the effect of overexpressed MeCP2 on NPCs differentiation, but also overexpression of miR-197 could reverse the NPCs differentiation defects caused by MECP2 mutations. Our results revealed that a regulatory axis involving MeCP2, miR-197, ADAM10, and NOTCH signaling is critical for NPC differentiation, which is affected by both MeCP2 duplication and mutation.
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Proteína ADAM10/biossíntese , Secretases da Proteína Precursora do Amiloide/biossíntese , Diferenciação Celular , Regulação Enzimológica da Expressão Gênica , Proteínas de Membrana/biossíntese , Proteína 2 de Ligação a Metil-CpG/metabolismo , MicroRNAs/metabolismo , Células-Tronco Neurais/metabolismo , Proteína ADAM10/genética , Secretases da Proteína Precursora do Amiloide/genética , Animais , Povo Asiático , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Linhagem Celular , China , Humanos , Proteínas de Membrana/genética , Proteína 2 de Ligação a Metil-CpG/genética , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Mutação de Sentido Incorreto , Células-Tronco Neurais/patologiaRESUMO
A channel of nanometre size is an important platform for nanofluidic investigations. In this work, we show that a single solid nanopore can be generated by hydrogen fluoride etching of the outside wall of commercially available fused silica capillary. The geometry, size and the singleness were characterized by various means, including scanning electron microscope, electrolyte conductance measurement and a fluorescent microscope. The generation principle is also discussed. The nanopore thus generated features in low aspect ratio and exhibits typical nanofluidic effects such as ion concentration polarization, rectification and molecular translocation.
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A star-shaped cyclometalated triruthenium complex 2(PF6)n (n = 3 and 4) with a triarylamine core was synthesized, which functions as a molecular switch with five well-separated redox states in both solution and film states. The single-crystal X-ray structure of 2(PF6)3 is presented. This complex displays four consecutive one-electron redox waves at +0.082, +0.31, +0.74, and +1.07 V vs Ag/AgCl. In each redox state, it shows significantly different NIR absorptions with λmax of 1590 nm for 24+, 1400 nm for 25+, 1060 nm for 26+, and 740 nm for 27+, respectively. Complex 24+ shows a single-line EPR signal at g = 2.060, while other redox states are all EPR inactive. The spin density distributions and NIR absorptions in different redox states were rationalized by DFT and TDDFT calculations. A vinyl-substituted triruthenium analogous 3(PF6)4 was prepared, which was successfully polymerized on ITO glass electrode surfaces by reductive electropolymerization. The obtained poly-3n+/ITO film was characterized by FTIR, AFM, and SEM analysis. It shows four well-defined redox couples and reversible multistate NIR electrochromism. In particular, a contrast ratio (ΔT%) up to 63% was achieved at the optic telecommunication wavelength (1550 nm).
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A series of cyclometalated diruthenium complexes with a redox-active amine bridge were synthesized. Depending on the terminal ligands of the ruthenium components and the substituent on the amine unit, the one-electron-oxidized state can be either in the form of a weakly or strongly coupled mixed-valence diruthenium complex, a fully charge-delocalized three-center system, or a bridge-biased electrophore. This transition among different electronic forms was supported by electrochemistry, near-infrared absorption, electron paramagnetic resonance, and density functional theory analysis.
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Through Ru(II)-catalyzed C-H bond activation, a methodology for the synthesis of 2- or 2,7-functionalized pyrene derivatives has been developed using the substrate 1-(pyrid-2-yl)pyrene or 1,6-di(pyrid-2-yl)pyrene.