RESUMO
Cyclic GMP-AMP synthase (cGAS) is a double-stranded DNA (dsDNA) sensor that functions in the innate immune system. Upon binding dsDNA, cGAS and dsDNA form phase-separated condensates in which cGAS catalyzes the synthesis of 2'3'-cyclic GMP-AMP that subsequently triggers a STING-dependent, type I interferon (IFN-I) response. Here, we show that cytoplasmic RNAs regulate cGAS activity. We discover that RNAs do not activate cGAS but rather promote phase separation of cGAS in vitro. In cells, cGAS colocalizes with RNA and forms complexes with RNA. In the presence of cytoplasmic dsDNA, RNAs colocalize with phase-separated condensates of cGAS and dsDNA. Further in vitro assays showed that RNAs promote the formation of cGAS-containing phase separations and enhance cGAS activity when the dsDNA concentration is low. Cotransfection of RNA with a small amount of dsDNA into THP1 cells significantly enhances the production of the downstream signaling molecule interferon beta (IFNB). This enhancement can be blocked by a cGAS-specific inhibitor. Thus, cytoplasmic RNAs could regulate cGAS activity by modulating the formation of cGAS-containing condensates.
Assuntos
Nucleotidiltransferases , RNA , RNA/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Interferon beta/genética , DNA/genética , DNA/metabolismo , Transdução de Sinais/genética , Imunidade Inata/genéticaRESUMO
A series of analogous chain selenite chlorides Ba2M(SeO3)2Cl2 (M = Cu 1, Ni 2, Co 3, Mn 4) and Pb2Cu(SeO3)2Cl2 5 with tunable spin S from S = 1/2 to S = 5/2 have been hydrothermally synthesized and characterized. These analogues crystallized in the orthorhombic Pnnm space group (monoclinic P21/n space group for 5) all containing M2+-SeO3-M2+ spin chains, which are further separated by the Ba2+ ions (Pb2+ for 5). The magnetic susceptibility results of 1, 2, and 5 show broad maxima around 80.0, 18.9, and 78.0 K, respectively, indicating good one-dimensional (1D) magnetism. Meanwhile, no long-range order (LRO) is observed down to 2 K for both 1 and 5, while the isostructural compounds 2, 3, and 4 exhibit LRO at 3.4 K, 10.8 K, and 5.7 K, respectively, which are further confirmed by the heat capacity and electron spin resonance results, as well as the observed spin-flop transitions in the M-H curves measured at 2 K below TN. The magnetizations of 1-5 at 7 T are still far from saturation. In addition, thermal stability and FT-IR and UV-vis-NIR spectroscopy of 1-5 are reported.
RESUMO
The environmental dissemination of extracellular antibiotic resistance genes (eARGs) in wastewater and natural water bodies has aroused growing ecological concerns. The coexisting chemical pollutants in water are known to markedly affect the eARGs transfer behaviors of the environmental microbial community, but the detailed interactions and specific impacts remain elusive so far. Here, we revealed a concentration-dependent impact of dimethyl phthalate (DMP) and several other types of phthalate esters (common water pollutants released from plastics) on the natural transformation of eARGs. The DMP exposure at an environmentally relevant concentration (10 µg/L) resulted in a 4.8-times raised transformation frequency of Acinetobacter baylyi but severely suppressed the transformation at a high concentration (1000 µg/L). The promotion by low-concentration DMP was attributed to multiple mechanisms, including increased bacterial mobility and membrane permeability to facilitate eARGs uptake and improved resistance of the DMP-bounded eARGs (via noncovalent interaction) to enzymatic degradation (with suppressed DNase activity). Similar promoting effects of DMP on the eARGs transformation were also found in real wastewater and biofilm systems. In contrast, higher-concentration DMP suppressed the eARGs transformation by disrupting the DNA structure. Our findings highlight a potentially underestimated eARGs spreading in aquatic environments due to the impacts of coexisting chemical pollutants and deepen our understanding of the risks of biological-chemical combined pollution in wastewater and environmental water bodies.
Assuntos
Resistência Microbiana a Medicamentos , Ácidos Ftálicos , Resistência Microbiana a Medicamentos/genética , Águas Residuárias , Biofilmes/efeitos dos fármacos , Poluentes Químicos da Água/toxicidadeRESUMO
The establishment of an appropriate costimulatory phenotype is crucial for dendritic cells (DCs) to maintain a homeostatic state with optimal immune surveillance and immunogenic activities. The upregulation of CD80/86 and CD40 is a hallmark costimulatory phenotypic switch of DCs from a steady state to an activated one for T cell activation. However, knowledge of the regulatory mechanisms underlying this process remains limited. In this study, we identified a Zbtb46 homolog from a zebrafish model. Zbtb46 deficiency resulted in upregulated cd80/86 and cd40 expression in kidney marrow-derived DCs (KMDCs) of zebrafish, which was accompanied with a remarkable expansion of CD4+/CD8+ T cells and accumulation of KMDCs in spleen of naive fish. Zbtb46 -/- splenic KMDCs exhibited strong stimulatory activity for CD4+ T cell activation. Chromatin immunoprecipitation-quantitative PCR and mass spectrometry assays showed that Zbtb46 was associated with promoters of cd80/86 and cd40 genes by binding to a 5'-TGACGT-3' motif in resting KMDCs, wherein it helped establish a repressive histone epigenetic modification pattern (H3K4me0/H3K9me3/H3K27me3) by organizing Mdb3/organizing nucleosome remodeling and deacetylase and Hdac3/nuclear receptor corepressor 1 corepressor complexes through the recruitment of Hdac1/2 and Hdac3. On stimulation with infection signs, Zbtb46 disassociated from the promoters via E3 ubiquitin ligase Cullin1/Fbxw11-mediated degradation, and this reaction can be triggered by the TLR9 signaling pathway. Thereafter, cd80/86 and cd40 promoters underwent epigenetic reprogramming from the repressed histone modification pattern to an activated pattern (H3K4me3/H3K9ac/H3K27ac), leading to cd80/86 and cd40 expression and DC activation. These findings revealed the essential role of Zbtb46 in maintaining DC homeostasis by suppressing cd80/86 and cd40 expression through epigenetic mechanisms.
Assuntos
Linfócitos T CD8-Positivos , Peixe-Zebra , Animais , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Antígenos CD40 , Moléculas de Adesão Celular/metabolismo , Células Dendríticas , Epigênese Genética , Ativação LinfocitáriaRESUMO
Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) that can recognize pathogen-associated molecular patterns (PMPs) and play important roles in the innate immune system in vertebrates. In this study, we identified a teleost-specific tlr22 gene from yellow catfish (Pelteobagrus fulvidraco) and its immune roles in response to different pathogens were also determined. The open reading frame (ORF) of the tlr22 was 2892 bp in length, encoding a protein of 963 amino acids. Multiple protein sequences alignment, secondary and three-dimensional structure analyses revealed that TLR22 is highly conserved among different fish species. Phylogenetic analysis showed that the phylogenetic topology was divided into six families of TLR1, TLR3, TLR4, TLR5, TLR7 and TLR11, and TLR22 subfamily was clustered into TLR11 family. Meanwhile, synteny and gene structure comparisons revealed functional and evolutionary conservation of the tlr22 gene in teleosts. Furthermore, tlr22 gene was shown to be widely expressed in detected tissues except barbel and eye, with highest expression level in liver. The transcription of tlr22 was significantly increased in spleen, kidney, liver and gill tissues at different timepoints after Poly I:C infection, suggesting TLR22 plays critical roles in defensing virus invasion. Similarly, the transcription of tlr22 was also dramatically up-regulated in spleen, kidney and gill tissues with different patterns after Aeromonas hydrophila infection, indicating that TLR22 is also involved in resisting bacteria invasion. Our findings will provide a solid basis for the investigation the immune functions of tlr22 gene in teleosts, as well as provide useful information for disease control and treatment for yellow catfish.
Assuntos
Peixes-Gato , Doenças dos Peixes , Animais , Regulação da Expressão Gênica , Aeromonas hydrophila/fisiologia , Filogenia , Receptores Toll-Like/genética , Poli I-C , Proteínas de Peixes/genéticaRESUMO
PURPOSE: Transjugular intrahepatic portosystemic shunt (TIPS) and splenectomy with periesophagogastric devascularization (SPD) are widely used to treat cirrhotic portal hypertension (PH) and prevent variceal rebleeding. However, direct comparisons between these two approaches are rare. This study was designed to compare the long-term outcomes of TIPS and SPD in patients with cirrhotic PH and variceal rebleeding. METHODS: The study included cirrhotic PH patients with a history of gastroesophageal variceal bleeding between 18 and 80 years of age who were admitted to the Third Affiliated Hospital of Sun Yat-sen University from January 2012 to January 2022. Patients were enrolled into two groups according to TIPS or SPD was performed. Baseline characteristics were matched using propensity score matching (PSM). RESULTS: A total of 230 patients underwent TIPS, while 184 underwent SPD. PSM was carried out to balance available covariates, resulting in a total of 83 patients in the TIPS group and 83 patients in the SPD group. Patients in SPD group had better liver function during 60 months follow-up. Five-year overall survival rates in SPD group and TIPS group were 72 and 27%, respectively, at 2 years were 88 and 86%, respectively. The 2- and 5-year freedom from variceal rebleeding rates were 95 and 80% in SPD group and 80 and 54% in TIPS group. CONCLUSIONS: SPD is clearly superior to TIPS in terms of OS and freedom from variceal rebleeding in patients with cirrhotic PH. In addition, SPD improved liver function in patients with cirrhotic PH.
Assuntos
Varizes Esofágicas e Gástricas , Hipertensão Portal , Derivação Portossistêmica Transjugular Intra-Hepática , Humanos , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Esplenectomia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Hipertensão Portal/complicações , Hipertensão Portal/cirurgia , Doença CrônicaRESUMO
Despite substantial advances that have been made in understanding the etiology of hepatocellular carcinoma (HCC), the early-stage diagnosis and treatment of advanced-stage HCC remain a major challenge. RNF8, an E3 ligase important for the DNA damage response, has been proven to facilitate the progression of breast and lung cancer, but its role in HCC remains unclear. In this study, we find that the expression of RNF8 is up-regulated in HCC tissues and positively correlated with poor prognosis of HCC. Furthermore, silencing RNF8 by siRNAs attenuates the migration of HCC cells and inhibits epithelial-mesenchymal transition (EMT) by regulating the expressions of proteins including N-cadherin, ß-catenin, snail, and ZO-1. Moreover, KaplanâMeier survival analysis shows that high RNF8 expression predicts poor survival benefits from sorafenib. Finally, cell viability assay demonstrates that RNF8 depletion enhances the sensitivity of HCC cells to sorafenib and lenvatinib treatment. We hypothesize that the inhibitory role of RNF8 in EMT and its enhancing effects on anti-cancer drugs orchestrate the protective effects of RNF8 deficiency in HCC, which indicates its potential in clinical application.
Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Transição Epitelial-Mesenquimal/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a DNA/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Objective To systematically analyze the current status of outcomes reporting in clinical trials on treating stasis acute mastitis with Traditional Chinese Medicine breast massage.Methods We searched CNKI, Wanfang, VIP, SinoMed, PubMed, Web of Science, Embase, Cochrane library, JBI, CINAHL, PsycINFO, Clinical Trials Registry Platform portal, Clinical Trials Registry, Australian New Zealand Clinical Trials Registry, Center Watch Registry from inception to May 15, 2022 to find randomized controlled trials, non-randomized controlled trials, case series and cohort studies which reported the outcomes of stasis acute mastitis managed with Traditional Chinese Medicine breast massage, with search terms of mastitis, acute mastitis, lactation mastitis, puerperal mastitis, breast problem, breast engorgement, milk stasis, blocked ducked, breast pain, breast massage, and acupoint massage. Outcomes and the measurement schemes (measurement methods, timing of assessing outcome, frequency of assessing outcome, measurers) were extracted from the included studies. We used the Management of Otitis Media with Effusion in Children with Cleft Palate (MOMENT) to assess the quality of each study, then categorized outcomes derived from the included studies into different domains according to the Outcome Measures in Rheumatology Arthritis Clinic Trials (OMERACT) Filter 2.1 framework.Results We identified 85 clinical trials, in which 54 different outcomes were reported. A total of 81.2% (69/85) of studies were assessed as medium quality with a mean score of 2.6, and 18.8% (16/85) as low quality with a mean score of 0.9. These outcomes were organized in three core areas. Lump size (89.4%, 76/85) was the most frequently reported outcome, followed by breast pain (69.4%, 59/85) and milk excretion (68.2%, 58/85). Five methods were used to assess lump size and four methods to assess breast pain.Conclusions The outcomes reported in clinical trials regarding stasis acute mastitis treated by Traditional Chinese Medicine breast massage are heterogeneous. Developing a core outcome set to achieve consistent standards for reporting outcomes and modalities for validation of the outcomes is clearly warranted.
Assuntos
Mastite , Mastodinia , Criança , Feminino , Humanos , Austrália , Massagem , Mastite/terapia , Medicina Tradicional ChinesaRESUMO
Probing the interfacial dynamics of single bacterial cells in complex environments is crucial for understanding the microbial biofilm formation process and developing antifouling materials, but it remains a challenge. Here, we studied single bacterial interfacial behaviors modulated by surfactants via a plasmonic imaging technique. We quantified the adhesion strength of single bacterial cells by plasmonic measurement of potential energy profiles and dissected the mechanism of surfactant-tuned single bacterial adhesion. The presence of surfactant tuned single bacterial adhesion by increasing the thickness of extracellular polymeric substances (EPS) and reducing the degree of EPS cross-linking. The adhesion kinetics and equilibrium state of bacteria attached to the surface confirmed the decrease in adhesion strength tuned by surfactants. The information obtained is valuable for understanding the interaction mechanism between a single bacterial cell and surface, developing new biofilm control strategies, and designing anticontamination materials. IMPORTANCE Studying the interfacial dynamic of single bacteria in complex environments is crucial for understanding the microbial biofilm formation process and developing antifouling materials. However, quantifying the interactions between microorganisms and surfaces in the presence of pollution at the single-cell level remains a great challenge. This paper presents the analysis of single bacterial interfacial behaviors modulated by surfactants and quantification of the adhesion strength via a plasmonic imaging technique. Our study provided insights into the mechanism of initial bacterial adhesion, facilitating our understanding of the adhesion process at the microscopic scale, and is of great value for controlling membrane fouling biofilm formation.
Assuntos
Aderência Bacteriana , Tensoativos , Tensoativos/farmacologia , Biofilmes , Matriz Extracelular de Substâncias PoliméricasRESUMO
A novel thiolysis-high-performance liquid chromatography method for the quantitative determination of total proanthocyanidins and the mean degree of polymerization in grape seeds has been developed. Following thiolysis with formic acid and benzyl mercaptan, reaction products were separated and purified. Three proanthocyanidin monomers and three derivatives were obtained and their structures were identified by liquid chromatography-mass spectrometry, FTIR spectroscopy, and NMR spectroscopy. A decomposition model of the thiolysis products and a correction formula for proanthocyanidins concentration were established. This thiolysis-high-performance liquid chromatography method displayed good calibration linearity (R2 > 0.999 over the concentration range 0.01 to 10 mg/mL), excellent accuracy (recoveries of 97.9-99.6%), and precision (repeatability relative standard deviations of 0.45-0.75%). This method is suitable for the quantitative analysis of proanthocyanidins in grape seed products.
Assuntos
Proantocianidinas , Vitis , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Proantocianidinas/análise , Sementes/química , Vitis/químicaRESUMO
Information thermodynamics has developed rapidly over past years, and the trapped ions, as a controllable quantum system, have demonstrated feasibility to experimentally verify the theoretical predictions in the information thermodynamics. Here, we address some representative theories of information thermodynamics, such as the quantum Landauer principle, information equality based on the two-point measurement, information-theoretical bound of irreversibility, and speed limit restrained by the entropy production of system, and review their experimental demonstration in the trapped ion system. In these schemes, the typical physical processes, such as the entropy flow, energy transfer, and information flow, build the connection between thermodynamic processes and information variation. We then elucidate the concrete quantum control strategies to simulate these processes by using quantum operators and the decay paths in the trapped-ion system. Based on them, some significantly dynamical processes in the trapped ion system to realize the newly proposed information-thermodynamic models is reviewed. Although only some latest experimental results of information thermodynamics with a single trapped-ion quantum system are reviewed here, we expect to find more exploration in the future with more ions involved in the experimental systems.
RESUMO
BACKGROUND: Metabolic syndrome (MetS) is an independent risk factor for the incidence of cardiovascular diseases. We investigated whether or to what extent MetS and its components was associated with coronary collateralization (CC) in chronic total occlusion (CTO). METHODS: This study involved 1653 inpatients with CTO. Data on demographic and clinical characteristics were collected by cardiovascular doctors. The CC condition was defined by the Rentrop scoring system. Subgroup analysis, mixed model regression analysis, scoring systems and receiver operating characteristic (ROC) curve analysis were performed. RESULTS: Overall, 1653 inpatients were assigned to the poor CC group (n = 355) and good CC group (n = 1298) with or without MetS. Compared to the good CCs, the incidence of MetS was higher among the poor CCs for all patients. Poor collateralization was present in 7.6%, 14.2%, 19.3%, 18.2%, 35.6% and 51.1% of the six groups who met the diagnostic criteria of MetS 0, 1, 2, 3, 4 and 5 times, respectively. For multivariable logistic regression, quartiles of BMI remained the risk factors for CC growth in all subgroups (adjusted OR = 1.755, 95% CI 1.510-2.038, P < 0.001 all patients; adjusted OR = 1.897, 95% CI 1.458-2.467, P < 0.001 non-MetS; and adjusted OR = 1.814, 95% CI 1.482-2.220, P < 0.001 MetS). After adjustment for potential confounding factors, MetS was an independent risk factor for CC growth in several models. Assigning a score of one for each component, the AUCs were 0.629 (95% CI 0.595-0.662) in all patients, 0.656 (95% CI 0.614-0.699) in MetS patients and 0.569 (95% CI 0.517-0.621) in non-MetS patients by receiver operating characteristic analysis. CONCLUSIONS: MetS, especially body mass index, confers a greater risk of CC formation in CTO. The value of scoring systems should be explored further for CTO.
Assuntos
Circulação Colateral , Circulação Coronária , Oclusão Coronária/fisiopatologia , Síndrome Metabólica/fisiopatologia , Idoso , Pequim/epidemiologia , Índice de Massa Corporal , Doença Crônica , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/epidemiologia , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Incidência , Pacientes Internados , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de RiscoRESUMO
Kin17 DNA and RNA binding protein (Kin17) is an extremely conserved nuclear protein that is almost expressed in every type of mammal cells. Recently, Kin17 has been implicated into the regulation of tumorigenesis of diverse human cancers. However, its functions in thyroid cancer (TC) are still largely unexplored. Kin17 mRNA and protein level were tested by qRT-PCR and western blot, respectively. Effects of Kin17 on TC cell proliferation were estimated by colony formation assay and flow cytometry analysis in vitro as well as by in vivo tumor growth experiment. TC cell migratory and invasive capacities were assessed via wound-healing and transwell experiments. Epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin and N-cadherin) and p38 MAPAK signaling pathway-related proteins (p-p38, p38, Cyclin D1, and p27) were examined via western blot. Kin17 was remarkably increased in TC tissue samples and cell lines at both mRNA and protein levels compared to normal tissue and control cell line. Knockdown of Kin17 obviously repressed TC cell proliferation, arrested cell cycle, and inhibited TC cell migration and invasion in vitro, while overexpression of Kin17 produced opposite effects. Kin17 knockdown suppressed p38 MAPK signaling pathway, while Kin17 overexpression activated this pathway. Treatment of p38 agonist (p79350) abolished the repressive effects of sh-Kin17 on TC cell proliferation, migration, and invasion, as well as on p38 pathway. Kin17 knockdown was also found to enhance the sensitivity of Doxorubicin of TC cells. In addition, Kin17 knockdown in vivo also markedly repressed TC tumor growth and p38 pathway. Kin17 functioned as an oncogene of TC by activating p38 MAPK signaling pathway.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Doxorrubicina/farmacologia , Proteínas de Ligação a RNA/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Humanos , Masculino , Camundongos Nus , Invasividade Neoplásica , Proteínas de Ligação a RNA/genética , Transdução de Sinais , Neoplasias da Glândula Tireoide/genética , Inibidores da Topoisomerase II/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/genéticaRESUMO
Rapid and accurate detection of pesticide and veterinary drug residues is a continuing challenge because of the complex matrix effects. Thus, appropriate sample pretreatment is a crucial step for the effective extraction of the analytes and removal of the interferences. Recently, the development of nanomaterial adsorbents has greatly promoted the innovation of food sample pretreatment approaches. Porous organic frameworks (POFs), including polymers of intrinsic microporosity, covalent organic frameworks, hyper crosslinked polymers, conjugated microporous polymers, and porous aromatic frameworks, have been widely utilized due to their tailorable skeletons and pores as well as fascinating features. This review summarizes the recent advances for POFs to be utilized in adsorption and sample preparation of pesticide and veterinary drug residues. In addition, future prospects and challenges are discussed, hoping to offer a reference for further study on POFs in sample pretreatment.
Assuntos
Estruturas Metalorgânicas , Praguicidas , Drogas Veterinárias , Adsorção , Praguicidas/análise , PorosidadeRESUMO
Discovery of new high-conductivity solid-state ionic conductors has been a long-lasting interest in the field of solid-state ionics for their important applications in solid-state electrochemical devices. Here, we report the mixed oxide-ion and Li-ion conductions, together with their conducting mechanisms in the Li2W2O7 material with triclinic symmetry. The process for the ionic identity is supported by several electrochemical measurements including electrochemical impedance spectroscopy, DC polarization, oxygen concentration cell, and theoretical analysis of neutron diffraction data and bond-valence-based energy landscape calculations. We show from electrochemical measurements strong evidences of the predominating oxide-ion conducting and minor Li-ion chemistry in Li2W2O7 at high temperatures, while the bond-valence-based energy landscape analysis reveals possible multidimensional ionic migration pathways for both oxide-ions and Li-ions. Thus, the presented results provide fundamental insights into new mixed ionic conduction mechanisms in low-symmetry materials and have implications for discoveries of new ionic conductors in years to come.
RESUMO
Mayenite Ca12Al14O33, as an oxide-ion conductor, has the potential of being applied in many fields, such as solid-oxide fuel cells. However, its relatively low oxide-ion conductivity hinders its wide practical applications and thus needs to be further optimized. Herein, a new recently developed glass crystallization route was used to prepare a series of Ga-doped Ca12Al14-xGaxO33 (0 ≤ x ≤ 14) materials, which is not accessible by the traditional solid-state reaction method. Phase evolution with the content of gallium, the corresponding structures, and their electrical properties were studied in detail. The X-ray diffraction data revealed that a pure mayenite phase can be obtained for 0 ≤ x ≤ 7, whereas when x > 7, the samples crystallize into a melilite-like orthorhombic Ca5Ga6O14-based phase. The electrical conduction studies evidence no apparent enhancement in the total conductivity for compositions 0 ≤ x ≤ 7 with the mayenite phase, and therefore, the rigidity of the framework cations and the width of the windows between cages are not key factors for oxide-ion conductivity in mayenite Ca12Al14O33-based materials, and changing the free oxygen content through aliovalent cation substitution may be the right direction. For compositions with a pure melilite-like orthorhombic phase, the conductivities also mirrored each other and are all slightly higher than those of the mayenite phases. These melilite-like Ca5Ga6O14-based materials show mixed Ca-ion, oxide-ion, and electron conduction. Furthermore, the conduction mechanisms of Ca ions and oxide ions in this composition were studied by a bond-valence-based method. The results suggested that Ca-ion conduction is mainly due to the severely underbonded Ca3 ions and that the oxide ions are most likely transported via oxygen vacancies.
RESUMO
Peroxynitrite (ONOO-), a highly reactive species, is profoundly involved in many physiological and pathological processes. Change of the ONOO- level usually indicates an abnormal body function. Thus, it is desired to develop a highly reliable ONOO- assay to elucidate its roles in a related disease environment. In this work, we have constructed a ratiometric molecule fluorescent probe RTFP toward ONOO- with high specificity by the combination strategy of probe screening and a rational design method. RTFP displayed excellent detection sensitivity (detection limit: 4.1 nM) and produced a highly ratiometric emission signal (130-fold). Leveraging this probe, we showed the change of ONOO- content in the free-fatty-acid-induced nonalcoholic fatty liver disease (NAFLD) and acetaminophen-induced drug-induced liver injury (DILI) cellular model and for the first time disclosed the involved mechanism of cytochrome P450 2E1 (CYP2E1) enzyme in NAFLD with a DILI pathological environment. Furthermore, RTFP also was utilized to visualize ONOO- fluctuation of living liver tissues in a high-fat-diet-caused NAFLD model. We expected that this probe may help the study of liver injury in the exploration of mechanism and signal path.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Corantes Fluorescentes/química , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ácido Peroxinitroso/análise , Acetaminofen , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Cumarínicos/química , Citocromo P-450 CYP2E1/metabolismo , Dieta Hiperlipídica , Ácidos Graxos , Células Hep G2 , Humanos , Limite de Detecção , Fígado/patologia , Camundongos , Microscopia de Fluorescência , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/patologiaRESUMO
Beyond their widespread application as genome-editing and regulatory tools, clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) systems also play a critical role in nucleic acid detection due to their high sensitivity and specificity. Recently developed Cas family effectors have opened the door to the development of new strategies for detecting different types of nucleic acids for a variety of purposes. Precise and efficient nucleic acid detection using CRISPR-Cas systems has the potential to advance both basic and applied biological research. In this review, we summarize the CRISPR-Cas systems used for the recognition and detection of specific nucleic acids for different purposes, including the detection of genomic DNA, nongenomic DNA, RNA, and pathogenic microbe genomes. Current challenges and further applications of CRISPR-based detection methods will be discussed according to the most recent developments.
Assuntos
Sistemas CRISPR-Cas , DNA/genética , RNA/genética , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , DNA/análise , Humanos , Polimorfismo de Nucleotídeo Único , RNA/análiseRESUMO
The unique physical structure and chemical and electrical properties of graphene make it an ideal choice for sensor materials. The sensing platform of biomolecule functionalized graphene has received extensive attention due to its high sensitivity and selectivity, especially the biosensors constructed by combining antibodies, nucleic acids and enzymes that efficiently recognize specific targets with graphene having a large specific surface area and a fast electron transfer rate, which has become a significant research direction. In this paper, electrochemical biosensors based on graphene materials developed in recent years are summarized. The methods of functional modification of graphene, graphene oxide and reduced graphene oxide with antibodies, nucleic acids and enzymes are briefly described. In addition, the advantages and disadvantages of the constructed electrochemical biosensors in detecting pathogens and disease markers are also reviewed. Finally, we are optimistic about this prospect for the development direction and application prospects of such electrochemical biosensors.
Assuntos
Anticorpos/química , Biomarcadores/análise , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Enzimas/química , Grafite/química , Ácidos Nucleicos/química , Doença/classificação , HumanosRESUMO
BACKGROUND: Midkine (MK), a heparin-binding protein, participates in multiple cellular processes, such as immunity, cellular growth and apoptosis. Overwhelming evidence indicates that MK plays an important role in various pathological processes, including chronic inflammation, autoimmunity, cancer, and infection. Recent studies demonstrated that MK may be involved in the development of atherosclerosis, yet the mechanism has not been fully explored. Therefore, this study aims to investigate the effect and mechanism of MK on macrophage cholesterol efflux.MethodsâandâResults:Using Oil Red O staining, NBD-cholesterol fluorescence labeling and enzymatic methods, it observed that MK markedly promoted macrophage lipid accumulation. Liquid scintillation counting (LSC) showed that MK decreased cholesterol efflux. Moreover, cell immunofluorescence, western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) showed that MK downregulated ATP-binding membrane cassette transport protein A1 (ABCA1) expression. Functional promotion of ABCA1 expression attenuated the inhibitory effects of MK on cholesterol efflux, which reduced lipid accumulation. Additionally, intervention of adenosine monophosphate activated protein (AMPK)-mammalian target of rapamycin (mTOR) signaling molecule by the AMPK activator, AICAR, increased p-AMPK and ABCA1 expression, decreased p-mTOR expression and promoted cholesterol efflux, resulting in an obvious reduction in intracellular lipid content. CONCLUSIONS: These data suggest that MK reduces the expression of ABCA1, inhibits the efflux of cholesterol and promotes the accumulation of lipids in RAW264.7 macrophages, and AMPK-mTOR signaling is involved in MK-mediated regulation of cholesterol metabolism in RAW264.7 macrophages.