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Adsorption-desorption performance, electronic properties, and sensitivity of O-defective g-ZnO (ODZO) gas sensors for volatile organic compounds (VOCs) are calculated using density functional theory and nonequilibrium Green's formalism. The VOCs are CH2O, CH4, C2H4O, CH4O, and C2H6. The intrinsic g-ZnO (IZO) and ODZO exhibit strong adsorption capabilities for C2H4O and CH4O. The IZO (0.118 e) and ODZO (0.059 e), which act as electron donors, exhibit the highest charge transfer to CH2O, indicating a strong interaction. The VOCs adsorption on the IZO and ODZO systems maintain nonmagnetic semiconductor characteristics. Additionally, the introduction of an O-defect causes the adsorption energy and charge transfer amount of ODZO to show an overall decrease, indicating better desorption ability. Notably, the sensitivity results show that the ODZO gas sensors exhibit high sensitivity to CH2O (39.3%), C2H4O (29.0%), and CH4O (19.6%) at a voltage of 2.6 V, consistent with the adsorption-desorption performance and electronic properties.
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Depression triggered by harmful stress during adolescence is a common problem that can affect mental health. To date, the mechanisms underlying this type of depression remain unclear. One mechanism for the promotion of depression by chronic stress in adulthood is the loss of hippocampal microglia. Since deleterious stress in adolescence also activates microglia, we investigated the dynamic changes of microglia in the hippocampus in mice exposed to chronic unpredictable stress (CUS) in adolescence. Our results showed that 12 days of CUS stimulation in adolescence induced typical depression-like behaviors in adult mice, which were accompanied by a significant decrease and dystrophy of microglia in the dentate gyrus of the hippocampus. Further analysis showed that this decrease in microglia was mediated by the initial response of microglia to unpredictable stress in the dentate gyrus of the hippocampus and their subsequent apoptosis. Blocking the initial response of microglia to unpredictable stress by pretreatment with minocycline was able to prevent apoptosis and microglial decline as well as the development of depression-like behaviors in adult mice induced by adolescent CUS. Moreover, administration of lipopolysaccharide (LPS) or macrophage-colony stimulatory factor (M-CSF), two drugs that reversed microglia decline in the dentate gyrus, ameliorated the depression-like behaviors induced by CUS stimulation in adolescence. These findings reveal a novel mechanism for the development of depression-like behaviors in animals triggered by deleterious stress in adolescence and suggest that reversing microglial decline in the hippocampus may be a hopeful strategy for the treatment of depression triggered by deleterious stress in adolescence.
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Apoptose , Comportamento Animal , Depressão , Hipocampo , Microglia , Estresse Psicológico , Animais , Microglia/efeitos dos fármacos , Microglia/patologia , Estresse Psicológico/complicações , Estresse Psicológico/psicologia , Apoptose/efeitos dos fármacos , Camundongos , Masculino , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Comportamento Animal/efeitos dos fármacos , Minociclina/farmacologia , Camundongos Endogâmicos C57BL , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Modelos Animais de Doenças , Fatores Etários , Lipopolissacarídeos/farmacologiaRESUMO
BACKGROUND: Aging is the primary risk factor of most chronic diseases in humans, including cardiovascular diseases, osteoporosis and neurodegenerative diseases, which extensively damage the quality of life for elderly individuals. Aging is a multifaceted process with numerous factors affecting it. Efficient model organisms are essential for the research and development of anti-aging agents, particularly when investigating pharmacological mechanisms are needed. PURPOSE: This review discusses the application of Caenorhabditis elegans for studying aging and its related signaling pathways, and presents an overview of studies exploring the mechanism and screening of anti-aging agents in C. elegans. Additionally, the review summarizes related clinical trials of anti-aging agents to inspire the development of new medications. METHOD: Literature was searched, analyzed, and collected using PubMed, Web of Science, and Science Direct. The search terms used were "anti-aging", "medicinal plants", "synthetic compounds", "C. elegans", "signal pathway", etc. Several combinations of these keywords were used. Studies conducted in C. elegans or humans were included. Articles were excluded, if they were on studies conducted in silico or in vitro or could not offer effective data. RESULTS: Four compounds mainly derived through synthesis (metformin, rapamycin, nicotinamide mononucleotide, alpha-ketoglutarate) and four active ingredients chiefly obtained from plants (resveratrol, quercetin, Astragalus polysaccharide, ginsenosides) are introduced emphatically. These compounds and active ingredients exhibit potential anti-aging effects in preclinical and clinical studies. The screening of these anti-aging agents and the investigation of their pharmacological mechanisms can benefit from the use of C. elegans. CONCLUSION: Medicinal plants provide valuable resource for the treatment of diseases. A wide source of raw materials for the particular plant medicinal compounds having anti-aging effects meet diverse pharmaceutical requirements, such as immunomodulatory, anti-inflammation and alleviating oxidative stress. C. elegans possesses advantages in scientific research including short life cycle, small size, easy maintenance, genetic tractability and conserved biological processes related to aging. C. elegans can be used for the efficient and rapid evaluation of compounds with the potential to slow down aging.
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Envelhecimento , Caenorhabditis elegans , Plantas Medicinais , Caenorhabditis elegans/efeitos dos fármacos , Animais , Plantas Medicinais/química , Envelhecimento/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos , Metformina/farmacologia , Sirolimo/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/químicaRESUMO
The photophysical and chiroptical properties of a chiral biquinoline amphiphile were found to be closely related to its aggregate states. Photochromism through photo-induced radical and circularly polarized luminescence were realized in its gel state and thin film state, respectively.
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The precise manipulation of supramolecular polymorphs has been widely applied to control the morphologies and functions of self-assemblies, but is rarely utilized for the fabrication of circularly polarized luminescence (CPL) materials with tailored properties. Here, this work reports that an amphiphilic naphthalene-histidine compound (NIHis) readily self-assembled into distinct chiral nanostructures through pathway-dependent supramolecular polymorphism, which shows opposite and multistimuli responsive CPL signals. Specifically, NIHis display assembly-induced CPL from the polymorphic keto tautomer, which become predominant during enol-keto tautomerization shifting controlled by a bulk solvent effect. Interestingly, chiral polymorphs of nanofiber and microbelt with inverted CPL signals can be prepared from the same NIHis monomer in exactly the same solvent compositions and concentrations by only changing the temperature. The tunable CPL performance of the solid microbelts is realized under multi external physical or chemical stimuli including grinding, acid fuming, and heating. In particular, an emission color and CPL on-off switch based on the microbelt polymorph by reversible heating-cooling protocol is developed. This work brings a new approach for developing smart CPL materials via supramolecular polymorphism engineering.
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The gas sensitivity of the W defect in WS2 (VW/WS2) to five toxic gases-HCHO, CH4, CH3HO, CH3OH, and CH3CH3-has been examined in this article. These five gases were adsorbed on the VW/WS2 surface, and the band, density of state (DOS), charge density difference (CDD), work function (W), current-voltage (I-V) characteristic, and sensitivity of adsorption systems were determined. Interestingly, for HCHO-VW/WS2, the energy level contribution of HCHO is closer to the Fermi level, the charge transfer (B) is the largest (0.104 e), the increase in W is more obvious than other adsorption systems, the slope of the I-V characteristic changes more obviously, and the calculated sensitivity is the highest. To sum up, VW/WS2 is more sensitive to HCHO. In conclusion, VW/WS2 has a great deal of promise for producing HCHO chemical sensors due to its high sensitivity and selectivity for HCHO, which can aid in the precise and efficient detection of toxic gases.
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Solid-state batteries based on lithium metal anodes are expected to meet safety challenges while maintaining a high energy density. One major challenge lies in the fast interface degradation between the electrolyte and the lithium metal. Herein, we propose a quasi-3D interphase on a garnet solid-state electrolyte (SSE) by introducing lithiophilic nanotrenches. The nanotrenches created by the lithiophilic nanowire array can induce the superfilling of lithium metal into the nanotrenches, resulting in a low interfacial resistance (4 Ω cm2). Moreover, the embedded lithium metal anode optimizes the lithium deposition/stripping behavior not limited at the Li-SSE interface (â¼1-10 nm) but extended into the bulk lithium anode (â¼10 µm), realizing a high critical current density of 1.8-2.0 mA cm-2 at room temperature (RT). The embedded lithium metal anode is further applied in Li||LiFePO4 solid-state batteries, demonstrating a high reversible areal capacity of â¼3.0 mAh cm-2 at RT.
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BACKGROUND: Primary biliary cholangitis (PBC) is a chronic immune-mediated liver disease. Previous genome-wide meta-analysis has identified the association between variants in TMEM163 with PBC. Here we aimed to evaluate the association between variants near the reported risk loci of TMEM163 at 2q21.3 and prognosis of PBC patients. METHODS: We performed a retrospective analysis of 347 PBC patients treated with ursodeoxycholic acid (UDCA) for at least 1 year. We collected clinical data at diagnosis and 1 year after UDCA treatment. SNPs within 200 kb upstream and downstream of the lead variant were genotyped and screened. RESULTS: We identified that rs661899 near MGAT5 and TMEM163 showed the strongest association with prognosis in PBC patients. Patients carrying the rs661899 T allele tended to respond incompletely to UDCA treatment and had worse performances in laboratory values including aspartate aminotransferase (53.5 vs 32 vs 28.5 U/L, p = 0.001), alkaline phosphate (157.25 vs 125 vs 113 U/L, p = 0.001), albumin (41.5 vs 42.3 vs 43.7 g/L, p = 0.008) and bilirubin (19.2 vs 14.9 vs 12.85 µmol/L, p = 0.001). GLOBE scores (p = 4.8 × 10-5) and UK-PBC risk scores (p = 4.6 × 10-4) were strongly correlated with rs661899 genotype. Patients with TT genotype had a higher risk for adverse events compared with CC genotype (p = 0.039) during the 1-year follow-up. Results were also verified in an independent cohort. CONCLUSIONS: PBC patients carrying the rs661899 T allele are associated with poor prognosis and adverse outcomes after 1-year UDCA therapy.
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Colangite , Cirrose Hepática Biliar , Humanos , Ácido Ursodesoxicólico/uso terapêutico , Cirrose Hepática Biliar/tratamento farmacológico , Cirrose Hepática Biliar/genética , Cirrose Hepática Biliar/complicações , Estudos Retrospectivos , Colagogos e Coleréticos/uso terapêutico , Resultado do Tratamento , Prognóstico , Proteínas de Membrana/genéticaRESUMO
A moxibustion device with the functions of auricular fumigation moxibustion and heat-sensitive moxibustion is designed. The smoke of the ignited moxa stick is used for the fumigation moxibustion at the external auditory canal, while the heat generated works on Dazhui (GV 14) for heat-sensitive moxibustion. The device consists of five parts, i.e. combustion chamber, smoke pipe, smoke processing chamber, power module and connector. It solves the limitations such as unpleasant experience in treatment, unfavorable temperature control, easy scalding and excessive manual dependence induced by usual fumigation moxibustion and during heat-sensitive moxibustion. This moxibustion device may improve the safety and convenience when delivering the treatment with fumigation moxibustion and heat-sensitive moxibustion, as well as the work efficiency of medical staff.
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Moxibustão , Humanos , Temperatura Alta , Fumigação , Fumaça , TemperaturaRESUMO
OBJECTIVE: Body fluid mixtures are complex biological samples that frequently occur in crime scenes, and can provide important clues for criminal case analysis. DNA methylation assay has been applied in the identification of human body fluids, and has exhibited excellent performance in predicting single-source body fluids. The present study aims to develop a methylation SNaPshot multiplex system for body fluid identification, and accurately predict the mixture samples. In addition, the value of DNA methylation in the prediction of body fluid mixtures was further explored. METHODS: In the present study, 420 samples of body fluid mixtures and 250 samples of single body fluids were tested using an optimized multiplex methylation system. Each kind of body fluid sample presented the specific methylation profiles of the 10 markers. RESULTS: Significant differences in methylation levels were observed between the mixtures and single body fluids. For all kinds of mixtures, the Spearman's correlation analysis revealed a significantly strong correlation between the methylation levels and component proportions (1:20, 1:10, 1:5, 1:1, 5:1, 10:1 and 20:1). Two random forest classification models were trained for the prediction of mixture types and the prediction of the mixture proportion of 2 components, based on the methylation levels of 10 markers. For the mixture prediction, Model-1 presented outstanding prediction accuracy, which reached up to 99.3% in 427 training samples, and had a remarkable accuracy of 100% in 243 independent test samples. For the mixture proportion prediction, Model-2 demonstrated an excellent accuracy of 98.8% in 252 training samples, and 98.2% in 168 independent test samples. The total prediction accuracy reached 99.3% for body fluid mixtures and 98.6% for the mixture proportions. CONCLUSION: These results indicate the excellent capability and powerful value of the multiplex methylation system in the identification of forensic body fluid mixtures.
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Lithium-sulfur battery is the most promising candidate for the next generation of rechargeable batteries because of the high energy density. However, the severe shuttle effect of lithium polysulfides (LiPSs) and degradation of the lithium anode during cycling are significant issues that hinder the practical application of lithium-sulfur batteries. Herein, monodispersed metal-organic framework (MOF)-modified nanofibers are prepared as building blocks to construct both a separator and a composite polymer electrolyte in lithium-sulfur systems. This building block possesses the intrinsic advantages of good mechanical properties, thermal stability, and good electrolyte affinity. MOFs, grown continuously on the monodispersed nanofibers, can effectively adsorb LiPSs and play a key role in regulating the nucleation and stripping/plating process of the lithium anode. When assembled into the separator, the symmetric battery remains stable for 2500 h at a current density of 1 mA cm-2, and the lithium-sulfur full cell shows improved electrochemical performance. In order to improve the safety property, the composite polymer electrolyte is prepared with the MOF-modified nanofiber as the filler. The quasi-solid-state symmetric battery remains stable for 3000 h at a current density of 0.1 mA cm-2, and the corresponding lithium-sulfur cell can cycle 800 times at 1 C with a capacity decay rate of only 0.038% per cycle.
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An automatic ash-removal heat-sensitive moxibustion device was developed, which could keep relatively constant temperature of heat-sensitive moxibustion, and realize the automatic ignition and automatic ash removal of moxa sticks during heat-sensitive moxibustion. The automatic ash-removal heat-sensitive moxibustion device comprises a bracket and a moxibustion box fixed on the top of the bracket; the bracket is composed of a base and a movable telescopic arm. This device can solve the problems of temperature instability, moxa ash blocking heat transfer and moxa ash falling during heat-sensitive moxibustion, avoiding the scalding caused by moxa ash falling, and reduce the workload of medical staff.
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Temperatura Alta , Moxibustão , Humanos , TemperaturaRESUMO
Scholars have long questioned whether the traditional media effects approach can still be applied in the current digital media era, especially in the non-Western, state-regulated Chinese media environment. This study examines the intermedia agenda setting of traditional media sources and we-media sources in the WeChat Official Accounts through a computational look at the Changsheng Bio-technology vaccine (CBV) crisis. Utilizing LDA topic modeling and Granger causality analysis, results show that both traditional media and we-media (i.e., online news sources operated by individuals or collectives) focus more consistently on two frames, the news facts and the countermeasure and suggestion frames. Interestingly, the traditional media agenda impacts the we-media agenda under the news fact and the countermeasure and suggestion frames, while the we-media agenda influences the traditional media agenda under the moral judgment and causality background frames. Overall, our study demonstrates the mutual effects between the traditional media agenda and the we-media agenda. This study sheds light on the theoretical meaning of network agenda setting and extends its application to social media platforms in Eastern countries and health-related fields.
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Mídias Sociais , Vacinação , Vacinas , Humanos , Povo Asiático , Internet , Meios de Comunicação de Massa , Vacinação/psicologiaRESUMO
Genome-wide association studies have identified 19p13.3 locus associated with primary biliary cholangitis (PBC). Here we aim to identify causative variant(s) and initiate efforts to define the mechanism by which the 19p13.3 locus variant(s) contributes to the pathogenesis of PBC. A genome-wide meta-analysis of 1931 PBC subjects and 7852 controls in two Han Chinese cohorts confirms the strong association between 19p13.3 locus and PBC. By integrating functional annotations, luciferase reporter assay and allele-specific chromatin immunoprecipitation, we prioritize rs2238574, an AT-Rich Interaction Domain 3A (ARID3A) intronic variant, as a potential causal variant at 19p13.3 locus. The risk allele of rs2238574 shows higher binding affinity of transcription factors, leading to an increased enhancer activity in myeloid cells. Genome-editing demonstrates the regulatory effect of rs2238574 on ARID3A expression through allele-specific enhancer activity. Furthermore, knock-down of ARID3A inhibits myeloid differentiation and activation pathway, and overexpression of the gene has the opposite effect. Finally, we find ARID3A expression and rs2238574 genotypes linked to disease severity in PBC. Our work provides several lines of evidence that a non-coding variant regulates ARID3A expression, presenting a mechanistic basis for association of 19p13.3 locus with the susceptibility to PBC.
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Predisposição Genética para Doença , Cirrose Hepática Biliar , Humanos , Estudo de Associação Genômica Ampla , Cirrose Hepática Biliar/genética , Cirrose Hepática Biliar/patologia , Genótipo , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genéticaRESUMO
PURPOSE: Glioblastoma(GBM) is a lethal disease characterized by inevitable recurrence. Here we investigate the molecular pathways mediating resistance, with the goal of identifying novel therapeutic opportunities. EXPERIMENTAL DESIGN: We developed a longitudinal in vivo recurrence model utilizing patient-derived explants to produce paired specimens(pre- and post-recurrence) following temozolomide(TMZ) and radiation(IR). These specimens were evaluated for treatment response and to identify gene expression pathways driving treatment resistance. Findings were clinically validated using spatial transcriptomics of human GBMs. RESULTS: These studies reveal in replicate cohorts, a gene expression profile characterized by upregulation of mesenchymal and stem-like genes at recurrence. Analyses of clinical databases revealed significant association of this transcriptional profile with worse overall survival and upregulation at recurrence. Notably, gene expression analyses identified upregulation of TGFß signaling, and more than one-hundred-fold increase in THY1 levels at recurrence. Furthermore, THY1-positive cells represented <10% of cells in treatment-naïve tumors, compared to 75-96% in recurrent tumors. We then isolated THY1-positive cells from treatment-naïve patient samples and determined that they were inherently resistant to chemoradiation in orthotopic models. Additionally, using image-guided biopsies from treatment-naïve human GBM, we conducted spatial transcriptomic analyses. This revealed rare THY1+ regions characterized by mesenchymal/stem-like gene expression, analogous to our recurrent mouse model, which co-localized with macrophages within the perivascular niche. We then inhibited TGFBRI activity in vivo which decreased mesenchymal/stem-like protein levels, including THY1, and restored sensitivity to TMZ/IR in recurrent tumors. CONCLUSIONS: These findings reveal that GBM recurrence may result from tumor repopulation by pre-existing, therapy-resistant, THY1-positive, mesenchymal cells within the perivascular niche.
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Neoplasias Encefálicas , Glioblastoma , Animais , Camundongos , Humanos , Glioblastoma/metabolismo , Linhagem Celular Tumoral , Neoplasias Encefálicas/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/tratamento farmacológico , Temozolomida/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Antineoplásicos Alquilantes/farmacologiaRESUMO
Lead (Pb) discharged from rural industries poses a significant threat to the environment and human health. Algal-bacterial aerobic granular sludge (A-B AGS) is a promising alternative for sewage treatment with high efficiency and good settleability. In this study, Pb(II) biosorption using fresh A-B AGS was investigated for the first time. The important role of extracellular polymeric substances (EPS) was revealed with the involved mechanisms being clarified. The desorbents for Pb recovery from Pb-loaded A-B AGS were also screened. Results showed that A-B AGS has an excellent maximum Pb adsorption capacity of 72.4 mg·g-1 at pH 6.0. EPS plays an important role in keeping microbial activity, Pb bonding, and providing metal ions (Ca, Na and Mg) for Pb ion exchanges. Electrostatic interaction, ion exchange, and bonding to functional groups may occur orderly in the Pb biosorption process and the formation of pyromorphite (Pb5(PO4)3Cl) contributes to Pb biosorption. About 66 % of the adsorbed Pb was accumulated in the A-B AGS microbial cells. Na2EDTA (0.05 M) can recover 60.3 % of the loaded Pb with the highest microbial activity of granules being remained. All the findings will provide the theoretical basis for the large-scale application of A-B AGS to bioremediate Pb(II)-containing wastewater.
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Matriz Extracelular de Substâncias Poliméricas , Esgotos , Humanos , Biodegradação Ambiental , Chumbo , Águas ResiduáriasRESUMO
Thermal-responsive hydrogel actuators have aroused a wide scope of research interest and have been extensively studied. However, their actuating behaviors are usually monotonous due to their unchangeable shapes and structures. Here, we report thermal-responsive poly(isopropylacrylamide-co-2-(dimethylamino)ethyl methacrylate)/alginate hydrogels with programmable external shapes and internal actuating trajectories. The volume phase transition temperatures of the resulting hydrogels can be tuned in a wide temperature range from 32 to above 50 °C by adjusting the monomer composition. While the formation and photo-dissociation of Fe3+-carboxylate tri-coordinates within the entire hydrogel network enable photo-responsive shape memory property, the insufficient dissociation of the tri-coordinates along the irradiation path gives rise to gradient crosslinking for realizing thermal-responsive actuation. Controlling the evolution of the gradient structure facilitates the regulation of the actuating amplitude. Furthermore, we show that the combination of these two types of shape-changing functionalities leads to more flexible and intricate shape-changing behaviors. One interesting application, a programmable hook with changeable actuating behaviors for lifting different objects with specific shapes, is also demonstrated. The proposed strategy can be extended to other types of actuating hydrogels with more advanced actuating behaviors.
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In autoimmune hepatitis (AIH), the persisting inflammation contributes to fibrosis progression, for which conventional biochemical markers manifest relatively unsatisfactory prediction. Herein, we assessed the value of serum CD48 (sCD48) as an indicator for inflammation and fibrosis in AIH type 1. The levels of sCD48 were detected first in an exploratory cohort using ELISA. In this cohort, compared with healthy controls (4.90 ng/mL, P < 0.0001), primary biliary cholangitis (7.32 ng/mL, P < 0.0001), and non-alcoholic fatty liver disease (7.76 ng/mL, P < 0.0001), sCD48 levels were elevated in AIH (12.81 ng/mL) and correlated with histological inflammation and fibrosis. Further using multivariate logistic regression analysis, sCD48 was identified as an independent predictor for both significant inflammation (G3-4) and advanced fibrosis (S3-4). Two predictive scores, based on sCD48, were constructed for diagnosing significant inflammation and advanced fibrosis (sCD48-AIH-SI and sCD48-AIH-AF, respectively). Using these data as a premise, predictive abilities were subsequently evaluated and verified in a validation cohort. In the exploratory cohort, the area under the receiver operating characteristic curve of sCD48 and sCD48-AIH-SI, for significant inflammation, were 0.748 and 0.813, respectively. Besides, during treatment follow-up, sCD48 levels gradually decreased from immunosuppression initiation to re-evaluation biopsy, in parallel with aspartate transaminase, total sera IgG, and fibrosis-4 score. For AIH patients in a re-evaluation biopsy cohort, sCD48 could predict significant fibrosis (S2-4). Further using immunohistochemistry, hepatic CD48 expression was elevated in AIH patients and decreased after treatment. In conclusion, sCD48 and sCD48-based predictive scores predict histological inflammation and fibrosis in AIH-1. Detecting sCD48 might help in the clinical management of AIH.
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Hepatite Autoimune , Humanos , Biomarcadores , Inflamação , FibroseRESUMO
Here, we combined the merits of emergent excitation-dependent (ExD) emission and circularly polarized luminescence to develop an excitation-dependent circularly polarized luminescence (ExD CPL) material showing unique features. A series of acylhydrazones based on a chiral tartaric skeleton was designed and found to self-assemble into helical nanostructures through non-covalent bonds. The helical assemblies showed ExD CPL due to the cooperation of chirality transfer and excited state intramolecular proton transfer (ESIPT). Remarkably, not only the emission wavelength could be tuned by the excitation wavelength but the handedness of CPL could be modulated in an inverted or ON/OFF manner as well, thus leading to the first example of an ExD inverted or ON/OFF switchable CPL system. Time-dependent density functional theory (TD-DFT) calculations were carried out to explain the inversion of ExD CPL. This work provided a new insight into the unprecedented handedness controllable ExD CPL, which showcased a new paradigm of the advanced CPL materials.
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Luminescência , Teoria da Densidade Funcional , TartaratosRESUMO
An ultrasensitive photoelectrochemical (PEC) analysis method based on terminal deoxynucleotidyl transferase (TdT) amplification effect and G-quadruplex/hemin (G4/hemin) catalytic reaction assisted signal amplification was prepared for the determination of ampicillin. A novel Au NPs@SnIn4S8-graphene sensitized structure was used as photoactive material to attain an intense basic photocurrent. In the presence of the target, P1 obtained by strand displacement reaction was introduced into the electrode surface, and abundant G4/hemin was formed in the presence of TdT and hemin. Subsequently, G4/hemin with horseradish peroxidase-mimicking activity catalyzed the oxidation of 4-chloro-1-naphthol by H2O2 to form benzo-4-chlorohexadienone precipitation on the modified electrode surface, which severely hindered the electron transfer and effectively inhibited the photocurrent output. The detection range of the PEC aptasensor for ampicillin was 10 fM-30 nM, and the limit of detection was 4.97 fM. The aptasensor had good stability and high sensitivity, and possessed a promising application in biological analysis and environmental monitoring.