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BACKGROUND: The Plant-specific AP2/ERF gene family encodes proteins involved in various biological and physiological processes. Although the genome of Coptis chinensis Franch, a plant producing benzylisoquinoline alkaloids (BIAs), has been sequenced at the chromosome level, studies on the AP2/ERF gene family in C. chinensis are lacking. Thus, a genome-wide identification of AP2/ERF gene family in C. chinensis was conducted to explore its role in BIAs biosynthesis. RESULTS: A total of 96 CcAP2/ERF genes were identified and categorized into five subfamilies, including 43 ERFs, 32 DREBs, 17 AP2s, 3 RAVs, and 1 Soloist, based on their structural domains. These CcAP2/ERF genes were unevenly distributed across nine chromosomes. Analysis of gene duplication events identified 17 CcAP2/ERF gene pairs in the genome, with 7 involved in tandem duplication events and 10 involved in segmental duplicate events, indicating that both types of duplications contributed to the expansion of the AP2/ERF gene family. The Ka/Ks ratio analysis suggested that the CcAP2/ERF gene family underwent strong purifying selection. Two phytohormones, methyl jasmonate and abscisic acid, were identified as potential key inducers of BIAs biosynthesis due to the cis-acting element prediction. Analysis of the spatial transcriptomic data revealed that 28 differentially expressed AP2/ERF genes had the highest or relatively higher expression levels in the rhizome, 17 of which positively correlated with the tissue-specific accumulation of BIAs. Further real-time PCR verification and protein-protein interaction analysis indicated that DREB1B might be one of the central regulators in a highly complex BIAs biosynthesis network. CONCLUSION: These findings provide significant insight into the function of AP2/ERF genes in C. chinensis, particularly in the regulatory network of BIAs biosynthesis in C. chinensis. This study also identifies candidate genes for metabolic engineering to increase BIAs content in C. chinensis.
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Benzilisoquinolinas , Coptis , Família Multigênica , Proteínas de Plantas , Coptis/genética , Coptis/metabolismo , Benzilisoquinolinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Regulação da Expressão Gênica de Plantas , Duplicação Gênica , Genoma de Planta , Especificidade de Órgãos/genéticaRESUMO
BACKGROUND: Arterial baroreflex dysfunction, like many other central nervous system disorders, involves disruption of the blood-brain barrier, but what causes such disruption in ABR dysfunction is unclear. Here we explored the potential role of platelets in this disruption. METHODS: ABR dysfunction was induced in rats using sinoaortic denervation, and the effects on integrity of the blood-brain barrier were explored based on leakage of Evans blue or FITC-dextran, while the effects on expression of CD40L in platelets and of key proteins in microvascular endothelial cells were explored using immunohistochemistry, western blotting and enzyme-linked immunosorbent assay. Similar experiments were carried out in rat brain microvascular endothelial cell line, which we exposed to platelets taken from rats with ABR dysfunction. RESULTS: Sinoaortic denervation permeabilized the blood-brain barrier and downregulated zonula occludens-1 and occludin in rat brain, while upregulating expression of CD40L on the surface of platelets and stimulating platelet aggregation. Similar effects of permeabilization and downregulation were observed in healthy rats that received platelets from animals with ABR dysfunction, and in rat brain microvascular endothelial cells, but only in the presence of lipopolysaccharide. These effects were associated with activation of NF-κB signaling and upregulation of matrix metalloprotease-9. These effects of platelets from animals with ABR dysfunction were partially blocked by neutralizing antibody against CD40L or the platelet inhibitor clopidogrel. CONCLUSION: During ABR dysfunction, platelets may disrupt the blood-brain barrier when CD40L on their surface activates NF-kB signaling within cerebral microvascular endothelial cells, leading to upregulation of matrix metalloprotease-9. Our findings imply that targeting CD40L may be effective against cerebral diseases involving ABR dysfunction.
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Barorreflexo , Plaquetas , Barreira Hematoencefálica , Ligante de CD40 , Permeabilidade Capilar , Modelos Animais de Doenças , Células Endoteliais , Metaloproteinase 9 da Matriz , NF-kappa B , Ratos Sprague-Dawley , Transdução de Sinais , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiopatologia , Barreira Hematoencefálica/patologia , Plaquetas/metabolismo , Masculino , Células Endoteliais/metabolismo , Ligante de CD40/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Ocludina/metabolismo , Linhagem Celular , Agregação Plaquetária , Pressão Arterial , RatosRESUMO
BACKGROUND: Inflammatory macrophage infiltration plays a critical role in acute kidney disease induced by ischemia-reperfusion (IRI-AKI). Calycosin is a natural flavone with multiple bioactivities. This study aimed to investigate the therapeutic role of calycosin in IRI-AKI and its underlying mechanism. METHODS: The renoprotective and anti-inflammatory effects of calycosin were analyzed in C57BL/6 mice with IRI-AKI and lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. RNA-seq was used for mechanism investigation. The molecular target of calycosin was screened by in silico methods and validated by surface plasmon resonance (SPR). Macrophage chemotaxis was analyzed using Transwell and agarose gel spot assays. RESULTS: Calycosin treatment significantly reduced serum creatinine and urea nitrogen and attenuated tubular destruction in IRI-AKI mice. Additionally, calycosin markedly suppressed NF-κB signaling activation and the expression of inflammatory mediators IL-1ß and TNF-α in IRI-AKI kidneys and LPS-stimulated RAW 264.7 cells. Interestingly, RNA-seq revealed calycosin remarkably downregulated chemotaxis-related pathways in RAW 264.7 cells. Among the differentially expressed genes, Ccl2/MCP-1, a critical chemokine mediating macrophage inflammatory chemotaxis, was downregulated in both LPS-stimulated RAW 264.7 cells and IRI-AKI kidneys. Consistently, calycosin treatment attenuated macrophage infiltration in the IRI-AKI kidneys. Importantly, in silico target prediction, molecular docking, and SPR assay demonstrated that calycosin directly binds to macrophage migration inhibitory factor (MIF). Functionally, calycosin abrogated MIF-stimulated NF-κB signaling activation and Ccl2 expression and MIF-mediated chemotaxis in RAW 264.7 cells. CONCLUSIONS: In summary, calycosin attenuates IRI-AKI by inhibiting MIF-mediated macrophage inflammatory chemotaxis, suggesting it could be a promising therapeutic agent for the treatment of IRI-AKI.
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Injúria Renal Aguda , Quimiotaxia , Isoflavonas , Fatores Inibidores da Migração de Macrófagos , Macrófagos , Traumatismo por Reperfusão , Animais , Masculino , Camundongos , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Quimiotaxia/efeitos dos fármacos , Oxirredutases Intramoleculares/metabolismo , Oxirredutases Intramoleculares/genética , Isoflavonas/farmacologia , Isoflavonas/uso terapêutico , Rim/efeitos dos fármacos , Rim/patologia , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Células RAW 264.7 , Traumatismo por Reperfusão/tratamento farmacológicoRESUMO
A simple and high-yielding strategy to produce a variety of ß-keto sulfides using asymmetrical and symmetrical thiosulfonates with ketones under mild conditions is reported. It was found that the various substituted compounds, with both electron-withdrawing and electron-donating substituents, afforded a wide range of ß-keto thiosulfones (α-thioaryl-ß-keto sulfones) in moderate to high yields. The transformations were reliable at the gram-scale, thus illustrating their efficiency and practicality. A plausible mechanism for the protocol is also proposed.
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A new chemodosimeter SWJT-31 with an aggregation-induced emission (AIE) effect was designed and constructed. Upon increasing the water fraction in the solution, it exhibited typical AIE, which showed bright red fluorescence at 610 nm. SWJT-31 could sensitively and specifically recognize hydrazine by the TICT effect with an LOD of 33.8 nM, which was much lower than the standard of the USEPA. A portable test strip prepared using SWJT-31 was also developed for the visual detection of hydrazine. Eventually, it was successfully used for the detection of hydrazine in water samples and HeLa cells.
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Corantes Fluorescentes , Hidrazinas , Imidazóis , Hidrazinas/química , Humanos , Células HeLa , Imidazóis/química , Imidazóis/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Imagem Óptica , Estrutura MolecularRESUMO
Two-dimensional (2D) carbon nitride materials have emerged as a versatile platform for the design of high-performance nanoelectronics, but strong anisotropy in 2D carbon nitrides has rarely been reported. In this work, a 2D carbon nitride with strong anisotropy composed of tetra-, penta-, and hexa-rings (named as TPH-C5N3) is proposed. This TPH-C5N3 exhibits both dynamical and mechanical stability. Furthermore, it also showcases remarkable thermal stability, reaching up to 2300 K, as evidenced by AIMD simulations conducted in an NVT environment utilizing the Nosé-Hoover thermostat. Significantly, TPH-C5N3 demonstrates high anisotropic ratios in its mechanical properties, positioning it as the frontrunner in the current carbon nitride systems. In addition, a Dirac cone with an anisotropic ratio of 55.8% and Fermi velocity of 7.26 × 105 m s-1 is revealed in TPH-C5N3. The nontrivial topological properties of TPH-C5N3 are demonstrated by a non-zero Z2 invariant and topologically protected edge states. Our study offers theoretical insights into an anisotropic 2D carbon nitride material, laying the groundwork for its design and synthesis.
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Two-dimensional material-supported single metal atom catalysts have been extensively studied and proved effective in electrocatalytic reactions in recent years. In this work, we systematically investigate the OER catalytic properties of single metal atoms supported by the NiN2 monolayer. Several typical transition metals with high single atom catalytic activity, such as Fe, Co, Ru, Rh, Pd, Ir, and Pt, were selected as catalytic active sites. The energy calculations show that transition metal atoms (Fe, Co, Ru, Rh, Pd, Ir, and Pt) are easily embedded in the NiN2 monolayer with Ni vacancies due to the negative binding energy. The calculated OER overpotentials of Fe, Co, Ru, Rh, Pd, Ir and Pt embedded NiN2 monolayers are 0.92 V, 0.47 V, 1.13 V, 0.66 V, 1.25 V, 0.28 V, and 0.94 V, respectively. Compared to the 0.57 V OER overpotential of typical OER noble metal catalysts IrO2, Co@NiN2 and Ir@NiN2 exhibit high OER catalytic activity due to lower overpotential, especially for Ir@NiN2. The high catalytic activity of the Ir embedded NiN2 monolayer can be explained well by the d-band center model. It is found that the adsorption strength of the embedded TM atoms with intermediates follows a linear relationship with their d-band centers. Besides, the overpotential of the Ir embedded NiN2 monolayer can be further reduced to 0.24 V under -2% biaxial strain. Such findings are expected to be employed in more two-dimensional material-supported single metal atom catalyzed reactions.
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The assembly of uniform nanocrystal building blocks into well ordered superstructures is a fundamental strategy for the generation of meso- and macroscale metamaterials with emergent nanoscopic functionalities1-10. The packing of spherical nanocrystals, which frequently adopt dense, face-centred-cubic or hexagonal-close-packed arrangements at thermodynamic equilibrium, has been much more widely studied than that of non-spherical, polyhedral nanocrystals, despite the fact that the latter have intriguing anisotropic properties resulting from the shapes of the building blocks11-13. Here we report the packing of truncated tetrahedral quantum dot nanocrystals into three distinct superstructures-one-dimensional chiral tetrahelices, two-dimensional quasicrystal-approximant superlattices and three-dimensional cluster-based body-centred-cubic single supercrystals-by controlling the assembly conditions. Using techniques in real and reciprocal spaces, we successfully characterized the superstructures from their nanocrystal translational orderings down to the atomic-orientation alignments of individual quantum dots. Our packing models showed that formation of the nanocrystal superstructures is dominated by the selective facet-to-facet contact induced by the anisotropic patchiness of the tetrahedra. This study provides information about the packing of non-spherical nanocrystals into complex superstructures, and may enhance the potential of self-assembled nanocrystal metamaterials in practical applications.
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OBJECTIVE: This study aimed to investigate the risk factors relating to the need for mechanical ventilation (MV)in isolated cervical spinal cord injury (cSCI) patients and to construct a nomogram prediction model. DESIGN: Retrospective analysis study. PARTICIPANTS: A total of 5784 patients (N=5784) who had a cSCI were admitted to the National Spinal Cord Injury Model System database (NSCID) between 2006 and 2021. SETTING: NSCID observation data was initially collected during rehabilitation hospitalization. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): A univariate and multivariate logistic regression analysis was used to identify the independent factors affecting the use of MV in cSCI patients, these independent influencing factors were used to develop a nomogram prediction model. The area under the receivers operating characteristic curve (AUROC), calibration curve and decision curve analysis (DCA) were employed to evaluate the efficiency and the clinical application value of the model respectively. RESULTS: In a series of 5784 included patients, 926 cases (16.0%) were admitted to spinal cord model system inpatient rehabilitation with the need of MV. Logistic regression analysis demonstrated that associated injury, American Spinal Cord Injury Association (ASIA) impairment scale (AIS), the sum of unilateral optimal motor scores for each muscle segment of upper extremities (sUEM) and neurological level of injury (NLI) were independent predictors of the use of MV (p<0.05). The prediction nomogram of MV usage in cSCI patients was established based on the above independent predictors. The AUROC of the training set, internal verification set and external verification set were 0.871 (0.857-0.886), 0.867 (0.843-0.891) and 0.850 (0.824-0.875) respectively. The calibration curve and DCA results showed that the model had a good calibration and clinical practicability. CONCLUSION: The nomograph prediction model based on sUEM, NLI, associated injury and AIS can accurately and effectively predict the risk of MV in cSCI patients, to help clinicians screen high-risk patients and formulate targeted intervention measures.
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OBJECTIVE: Although some studies have examined the association between eating behaviour and elevated blood pressure (EBP) in adolescents, current data on the association between sugar-sweetened beverages (SSB) and EBP in adolescents in Yunnan Province, China, are lacking. SETTING: Cluster sampling was used to survey freshmen at a college in Kunming, Yunnan Province, from November to December. Data on SSB consumption were collected using an FFQ measuring height, weight and blood pressure. A logistic regression model was used to analyse the association between SSB consumption and EBP, encompassing prehypertension and hypertension with sex-specific analyses. PARTICIPANTS: The analysis included 4781 college students. RESULTS: Elevated systolic blood pressure (SBP) and diastolic blood pressure (DBP) were detected in 35·10 % (1678/4781) and 39·34 % (1881/4781) of patients, respectively. After adjusting for confounding variables, tea beverage consumption was associated with elevated SBP (OR = 1·24, 95 % CI: 1·03, 1·49, P = 0·024), and carbonated beverage (OR = 1·23, 95 % CI: 1·04, 1·45, P = 0·019) and milk beverage (OR = 0·81, 95 % CI: 0·69, 0·95, P = 0·010) consumption was associated with elevated DBP in college students. Moreover, fruit beverage (OR = 1·32, 95 % CI: 1·00, 1·75, P = 0·048) and milk beverage consumption (OR = 0·69, 95 % CI: 0·52, 0·93, P = 0·014) was associated with elevated DBP in males. CONCLUSION: Our findings indicated that fruit and milk beverage consumption was associated with elevated DBP in males, and no association was observed with EBP in females.
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Hipertensão , Bebidas Adoçadas com Açúcar , Masculino , Feminino , Adolescente , Humanos , Bebidas Adoçadas com Açúcar/efeitos adversos , Pressão Sanguínea , Sacarose Alimentar/efeitos adversos , China/epidemiologia , Bebidas , Bebidas Gaseificadas , Hipertensão/epidemiologia , Hipertensão/etiologia , EstudantesRESUMO
Critically ill COVID-19 patients may exhibit various clinical symptoms of renal dysfunction including severe Acute Kidney Injury (AKI). Currently, there is a lack of bibliometric analyses on COVID-19-related AKI. The aim of this study is to provide an overview of the current research status and hot topics regarding COVID-19 AKI. The literature was retrieved from the Web of Science Core Collection (WoSCC) database. Subsequently, we utilized Microsoft Excel, VOSviewer, Citespace, and Pajek software to revealed the current research status, emerging topics, and developmental trends pertaining to COVID-19 AKI. This study encompassed a total of 1507 studies on COVID-19 AKI. The United States, China, and Italy emerged as the leading three countries in terms of publication numbers, contributing 498 (33.05%), 229 (15.20%), and 140 (9.29%) studies, respectively. The three most active and influential institutions include Huazhong University of Science and Technology, Wuhan University and Harvard Medical School. Ronco C from Italy, holds the record for the highest number of publications, with a total of 15 papers authored. Cheng YC's work from China has garnered the highest number of citations, totaling 470 citations. The co-occurrence analysis of author keywords reveals that 'mortality', 'intensive care units', 'chronic kidney disease', 'nephrology', 'renal transplantation', 'acute respiratory distress syndrome', and 'risk factors' emerge as the primary areas of focus within the realm of COVID-19 AKI. In summary, this study analyzes the research trends in the field of COVID-19 AKI, providing a reference for further exploration and research on COVID-19 AKI mechanisms and treatment.
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Injúria Renal Aguda , Bibliometria , COVID-19 , Pandemias , SARS-CoV-2 , Humanos , COVID-19/complicações , COVID-19/epidemiologia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/complicações , Itália/epidemiologia , Betacoronavirus , China/epidemiologia , Saúde GlobalRESUMO
The Astragalus mongholicus Bunge and Panax notoginseng formula (A&P) has been clinically shown to effectively slow down the progression of chronic kidney disease (CKD) and has demonstrated significant anti-fibrosis effects in experimental CKD model. However, the specific active ingredients and underlying mechanism are still unclear. The active ingredients of A&P were analyzed by Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-HR-MS). A mouse model of CKD was constructed by 5/6 nephrectomy. Renal function was assessed by creatinine and urea nitrogen. Real-time PCR and Western Blot were performed to detect the mRNA and protein changes in kidney and cells. An in vitro fibrotic cell model was constructed by TGF-ß induction in TCMK-1 cells. The results showed that thirteen active ingredients of A&P were identified by UPLC-HR-MS, nine of which were identified by analysis with standards, among which the relative percentage of NOB was high. We found that NOB treatment significantly improved renal function, pathological damage and reduced the expression level of fibrotic factors in CKD mice. The results also demonstrated that Lgals1 was overexpressed in the interstitial kidney of CKD mice, and NOB treatment significantly reduced its expression level, while inhibiting PI3K and AKT phosphorylation. Interestingly, overexpression of Lgals1 significantly increased fibrosis in TCMK1 cells and upregulated the activity of PI3K and AKT, which were strongly inhibited by NOB treatment. NOB is one of the main active components of A&P. The molecular mechanism by which NOB ameliorates renal fibrosis in CKD may be through the inhibition of Lgals1/PI3K/AKT signaling pathway.
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Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Fibrose , Flavonas , Rim , Panax notoginseng , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Insuficiência Renal Crônica , Transdução de Sinais , Animais , Camundongos , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Masculino , Panax notoginseng/química , Flavonas/farmacologia , Flavonas/uso terapêutico , Rim/patologia , Rim/efeitos dos fármacos , Astrágalo/química , Camundongos Endogâmicos C57BL , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta PressãoRESUMO
INTRODUCTION: Citri Sarcodactylis Fructus (CSF), a common fruit and traditional Chinese medicine (TCM), has been hindered in its further development and research owing to the lack of comprehensive and specific quality evaluation standards. OBJECTIVE: This study aimed to establish clear TCM quality standards related to the therapeutic mechanisms of CSF and to provide a basis for subsequent research and development. METHODS: Ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap high-resolution mass spectrometry (UPLC-Q-orbitrap HRMS) technology was used to comprehensively identify CSF components and explore their absorbance levels in rat serum. Network pharmacology research methods were employed to investigate the potential mechanisms of action of the identified components in the treatment of major clinical diseases. Subsequently, a combination of HPLC chromatographic fingerprinting for qualitative analysis and multi-index content determination was used to evaluate the detectability of the identified quality markers (Q-markers). RESULTS: Twenty-six prototype components were tentatively characterized in rat serum. Network pharmacology analysis showed six effective components, namely 7-hydroxycoumarin, isoscopoletin, diosmin, hesperidin, 5,7-dimethoxycoumarin, and bergapten, which played important roles in the treatment of chronic gastritis, functional dyspepsia, peptic ulcer, and depression and were preliminarily identified as Q-markers. The results of content determination in 15 batches of CSF indicated significant differences in the content of medicinal materials from different origins. However, compared with the preliminarily determined Q-markers, all six components could be measured and were determined as Q-markers of CSF. CONCLUSION: The chemical Q-markers obtained in this study could be used for effective quality control of CSF.
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Medicamentos de Ervas Chinesas , Farmacologia em Rede , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Farmacologia em Rede/métodos , Ratos , Ratos Sprague-Dawley , Frutas/química , Masculino , Controle de Qualidade , Citrus/química , Biomarcadores/sangue , Medicina Tradicional Chinesa , Diosmina/farmacologia , Diosmina/sangue , Cumarínicos/sangue , Cumarínicos/farmacologia , Espectrometria de Massas/métodos , FlavonoidesRESUMO
Small nucleic acid drugs mainly include small interfering RNA(siRNA), antisense oligonucleotide(ASO), microRNA(miRNA), messenger RNA(mRNA), nucleic acid aptamer(aptamer), and so on. Its translation or regulation can be inhibited by binding to the RNA of the target molecule. Due to its strong specificity, persistence, and curability, small nucleic acid drugs have received considerable attention in recent years. Recent studies have shown that some miRNAs from animal and plant sources can stably exist in the blood, tissue, and organs of animals and human beings and exert pharmacological action by regulating the expression of various target proteins. This paper summarized the discovery of small nucleic acids derived from traditional Chinese medicine(TCM) and natural drugs and their cross-border regulatory mechanisms and discussed the technical challenges and regulatory issues brought by this new drug, which can provide new ideas and methods for explaining the complex mechanism of TCM, developing new drugs of small nucleic acids from TCM and natural medicine, and conducting regulatory scientific research.
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Descoberta de Drogas , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , MicroRNAs/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/química , Ácidos Nucleicos/químicaRESUMO
Discrete oligomers can be used to precisely evaluate the structure-property relationship and enable unique chiroptical activities, however, the role of stereochemical sequences in chirality transfer is still unclear. Herein, we report the successful synthesis of a series of sequence-defined chiral azobenzene (Azo) oligomers via iterative stepwise chain growth strategy, and the discovery of controllable activation and deactivation of chirality transfer. Sequence-defined stereoisomers with one single chiral (L or D) stereocenter at the α-position, ω-position and middle- (m-) position have completely different self-assembly dynamics and chirality transfer mechanisms. ω-positional stereocenter can effectively command all Azo building blocks to adopt a tilted π-π stacking along the helical superbundles, exhibiting the activation of chirality transfer. However, discrete oligomers with the stereocenter at other positions can only self-assemble into non-helical nanowires, accompanied by the deactivation of chirality transfer. Kinetic experiments as well as chemical simulations indicate that the cooperative supramolecular interaction, including the π-π interaction between repeated Azo units, the intermolecular hydrogen bonding and steric hindrance, are intrinsic driving forces for these differentiations. This study has shed light on the unique self-assembled kinetics in stereosequential oligomers and the mechanism of chirality induction at hierarchical levels.
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Metallic zinc has emerged as a promising anode material for high-energy battery systems due to its high theoretical capacity (820 mA h g-1), low redox potential for two-electron reactions, cost-effectiveness and inherent safety. However, current zinc metal batteries face challenges in low coulombic efficiency and limited longevity due to uncontrollable dendrite growth, the corrosive hydrogen evolution reaction (HER) and decomposition of the aqueous ZnSO4 electrolyte. Here, we report an interfacial-engineering approach to mitigate dendrite growth and reduce corrosive reactions through the design of ultrathin selective membranes coated on the zinc anodes. The submicron-thick membranes derived from polymers of intrinsic microporosity (PIMs), featuring pores with tunable interconnectivity, facilitate regulated transport of Zn2+-ions, thereby promoting a uniform plating/stripping process. Benefiting from the protection by PIM membranes, zinc symmetric cells deliver a stable cycling performance over 1500 h at 1 mA/cm² with a capacity of 0.5 mAh while full cells with NaMnO2 cathode operate stably at 1 A g-1 over 300 cycles without capacity decay. Our work represents a new strategy of preparing multi-functional membranes that can advance the development of safe and stable zinc metal batteries.
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Quality control practices in the modern laboratory are the result of significant advances over the many years of the profession. Major advance in conventional internal quality control has undergone a philosophical shift from a focus solely on the statistical assessment of the probability of error identification to more recent thinking on the capability of the measurement procedure (e.g. sigma metrics), and most recently, the risk of harm to the patient (the probability of patient results being affected by an error or the number of patient results with unacceptable analytical quality). Nonetheless, conventional internal quality control strategies still face significant limitations, such as the lack of (proven) commutability of the material with patient samples, the frequency of episodic testing, and the impact of operational and financial costs, that cannot be overcome by statistical advances. In contrast, patient-based quality control has seen significant developments including algorithms that improve the detection of specific errors, parameter optimization approaches, systematic validation protocols, and advanced algorithms that require very low numbers of patient results while retaining sensitive error detection. Patient-based quality control will continue to improve with the development of new algorithms that reduce biological noise and improve analytical error detection. Patient-based quality control provides continuous and commutable information about the measurement procedure that cannot be easily replicated by conventional internal quality control. Most importantly, the use of patient-based quality control helps laboratories to improve their appreciation of the clinical impact of the laboratory results produced, bringing them closer to the patients.Laboratories are encouraged to implement patient-based quality control processes to overcome the limitations of conventional internal quality control practices. Regulatory changes to recognize the capability of patient-based quality approaches, as well as laboratory informatics advances, are required for this tool to be adopted more widely.
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Imaging-guided photothermal therapy (PTT) in a single nanoscale platform has aroused extensive research interest in precision medicine, yet only a few methods have gained wide acceptance. Thus, it remained an urgent need to facilely develop biocompatible and green probes with excellent theranostic capacity for superior biomedical applications. In this study, a smart chemical oxidative polymerization strategy was successfully developed for the synthesis of Au@PPy core-shell nanoparticles with polyvinyl alcohol (PVA) as the hydrophile. In the reaction, the reactant tetrachloroauric acid (HAuCl4) was reduced by pyrrole to fabricate a gold (Au) core, and pyrrole was oxidized to deposit around the Au core to form a polypyrrole (PPy) shell. The as-synthesized Au@PPy nanoparticles showed a regular core-shell morphology and good colloidal stability. Relying on the high X-ray attenuation of Au and strong near-infrared (NIR) absorbance of PPy and Au, Au@PPy nanoparticles exhibited excellent performance in blood pool/tumor imaging and PTT treatment by a series of in vivo experiments, in which tumor could be precisely positioned and thoroughly eradicated. Hence, the facile chemical oxidative polymerization strategy for constructing monodisperse Au@PPy core-shell nanoparticles with potential for cancer diagnosis and imaging-guided photothermal therapy shed light on an innovative design concept for the facile fabrication of biomedical materials.
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Nanopartículas , Neoplasias , Humanos , Polímeros , Terapia Fototérmica , Polimerização , Pirróis , Nanopartículas/uso terapêutico , Fototerapia/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Estresse Oxidativo , Ouro/uso terapêutico , Nanomedicina Teranóstica/métodosRESUMO
Arterial baroreflex (ABR) dysfunction has previously been associated with neuroinflammation, the most common pathological feature of neurological disorders. However, the mechanisms mediating ABR dysfunction-induced neuroinflammation are not fully understood. In the present study, we investigated the role of platelet CD40 ligand (CD40L) in neuroinflammation in an in vivo model of ABR dysfunction, and microglia and astrocyte activation in vitro. ABR dysfunction was induced in SpragueâDawley rats by sinoaortic denervation (SAD). We used ELSA and immunofluorescence to assess the effect of platelet CD40L on glial cell polarization and the secretion of inflammatory factors. By flow cytometry, we found that rats subjected to SAD showed a high level of platelet microaggregation and upregulation of CD40L on the platelet surface. The promotion of platelet invasion and accumulation was also observed in the brain tissues of rats subjected to SAD. In the animal model and cultured N9 microglia/C6 astrocytoma cells, platelet CD40L overexpression promoted neuroinflammation and activated M1 microglia, A1 astrocytes, and the nuclear factor kappa B (NFκB) signaling pathway. These effects were partially blocked by inhibiting platelet activity with clopidogrel or inhibiting CD40L-mediated signaling. Our results suggest that during ABR dysfunction, CD40L signaling in platelets converts microglia to the M1 phenotype and astrocytes to the A1 phenotype, activating NFκB and resulting in neuroinflammation. Thus, our study provides a novel understanding of the pathogenesis of ABR dysfunction-induced neuroinflammation and indicates that targeting platelet CD40L is beneficial for treating central nervous system (CNS) disorders associated with ABR dysfunction.
Assuntos
Astrócitos , Barorreflexo , Plaquetas , Ligante de CD40 , Microglia , NF-kappa B , Doenças Neuroinflamatórias , Transdução de Sinais , Animais , Masculino , Ratos , Astrócitos/metabolismo , Astrócitos/patologia , Plaquetas/metabolismo , Plaquetas/patologia , Ligante de CD40/metabolismo , Microglia/metabolismo , Microglia/patologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/patologia , NF-kappa B/metabolismo , Ativação Plaquetária , Ratos Sprague-DawleyRESUMO
A novel ratiometric probe (SWJT-10) based on isophorone derivatives has been designed and synthesized for the detection of formaldehyde (FA). This probe displayed an obvious ratiometric fluorescence response to FA with a blue shift from the NIR (680 nm) to the yellow light region (600 nm) in aqueous solution. And it showed good selectivity, high sensitivity and a fast response to FA (less than 5 s) due to a new recognition mechanism. Moreover, SWJT-10 has been applied to monitor FA in living cells and zebrafish.