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1.
Anal Chem ; 96(22): 9026-9033, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38771095

RESUMO

Precise detection of a trace substance that intrinsically possesses weak chemical activity and less-distinctive spatial structure is of great significance, but full of challenges, as it could not be effectively recognized via either an active covalent reaction process or multiple noncovalent interactions toward its simple structure. Here, the electronic-effect-driven recognition strategy was proposed to visually sense an illicit drug, γ-hydroxybutyric acid (GHB), which was treated as an analyte model due to its inherent simple structure. In particular, a sensing system composed of two probes substituted by the nitro (-NO2) and the hydrogen (-H), was constructed with the characteristic yellow coloring and blue fluorescence, as well as high sensitivity (0.586 ng/mL), fast response (0.2 s), and specific recognition, even in the presence of 22 interferents. In addition, a portable eyeshadow box-like sensing chip was fabricated and proven to be reliable and feasible in sensing GHB disguised in liquors for self-protection in a covert manner. Hence, this work developed an electronic-effect-driven modulation strategy of the recognition interaction between the probe and the analyte and, thus, would open up a new thought for detecting the analyte with weak activity and a simple structure, as well as propel the relevant application in real scenarios.

2.
Small ; : e2401024, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597755

RESUMO

Exposing different facets on metal-organic frameworks (MOFs) is highly desirable to enhance the performance for various applications, however, exploiting a concise and effective approach to achieve facet-controlled synthesis of MOFs remains challenging. Here, by modulating the ratio of metal precursors to ligands, the facet-engineered iron-based MOFs (Fe-MOFs) exhibits enhanced catalytic activity for Fenton reaction are explored, and the mechanism of facet-dependent performance is revealed in detail. Fully exposed (101) and (100) facets on spindle-shaped Fe-MOFs enable rapid oxidation of colorless o-phenylenediamine (OPD) to colored products, thereby establishing a dual-mode platform for the detection of hydrogen peroxide (H2O2) and triacetone triperoxide (TATP). Thus, a detection limit as low as 2.06 nm is achieved, and robust selectivity against a wide range of common substances (>16 types) is obtained, which is further improved by incorporating a deep learning architecture with an SE-VGG16 network model, enabling precise differentiation of oxidizing agents from captured images. The present strategy is expected will shine light on both the rational synthesis of nanomaterials with modulated morphologies and the exploitation of high-performance trace chemical sensors.

3.
BMC Gastroenterol ; 24(1): 146, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689244

RESUMO

BACKGROUND: The prevalence of neoplastic polyps in gallbladder polyps (GPs) increases sharply with age and is associated with gallbladder carcinoma (GBC). This study aims to predict neoplastic polyps and provide appropriate treatment strategies based on preoperative ultrasound features in patients with different age level. METHODS: According to the age classification of WHO, 1523 patients with GPs who underwent cholecystectomy from January 2015 to December 2019 at 11 tertiary hospitals in China were divided into young adults group (n=622), middle-aged group (n=665) and elderly group (n=236). Linear scoring models were established based on independent risk variables screened by the Logistic regression model in different age groups. The area under ROC (AUC) to evaluate the predictive ability of linear scoring models, long- and short- diameter of GPs. RESULTS: Independent risk factors for neoplastic polyps included the number of polyps, polyp size (long diameter), and fundus in the young adults and elderly groups, while the number of polyps, polyp size (long diameter), and polyp size (short diameter) in the middle-aged groups. In different age groups, the AUCs of its linear scoring model were higher than the AUCs of the long- and short- diameter of GPs for differentiating neoplastic and non-neoplastic polyps (all P<0.05), and Hosmer-Lemeshow goodness of fit test showed that the prediction accuracy of the linear scoring models was higher than the long- and short- diameter of GPs (all P>0.05). CONCLUSION: The linear scoring models of the young adults, middle-aged and elderly groups can effectively distinguish neoplastic polyps from non-neoplastic polyps based on preoperative ultrasound features.


Assuntos
Neoplasias da Vesícula Biliar , Pólipos , Ultrassonografia , Humanos , Pessoa de Meia-Idade , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/patologia , Feminino , Masculino , Estudos Retrospectivos , Adulto , Pólipos/diagnóstico por imagem , Pólipos/patologia , Fatores Etários , Idoso , Fatores de Risco , Colecistectomia , China/epidemiologia , Período Pré-Operatório , Adulto Jovem , Cuidados Pré-Operatórios
4.
BMC Infect Dis ; 24(1): 9, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166827

RESUMO

PURPOSE: The present study aims to investigate the potential of platelet distribution width as an useful parameter to assess the severity of influenza in children. METHODS: Baseline characteristics and laboratory results were collected and analyzed. Receiver operating characteristic (ROC) curve analysis was used to joint detection of inflammatory markers for influenza positive children, and the scatter-dot plots were used to compare the differences between severe and non-severe group. RESULTS: Influenza B positive children had more bronchitis and pneumonia (P < 0.05), influenza A infected children had more other serious symptoms (P = 0.007). Neutrophil count, lymphocyte count, neutrophil-to-lymphocyte ratio (NLR), and platelet parameters performed differently among < 4 years and ≥ 4 years children with influenza. Combined detection of platelet parameters and other indicators could better separate healthy children from influenza infected children than single indicator detection. The levels of platelet distribution width of children with severe influenza (A and B) infection was significantly dropped, compared with non-severe group (P < 0.05). CONCLUSIONS: Platelet distribution width could be a very useful and economic indicator in distinction and severity assessment for children with influenza.


Assuntos
Influenza Humana , Volume Plaquetário Médio , Criança , Humanos , Influenza Humana/diagnóstico , Contagem de Plaquetas , Contagem de Leucócitos , Linfócitos , Neutrófilos , Estudos Retrospectivos , Curva ROC
5.
J Phys Chem A ; 128(18): 3571-3578, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38656182

RESUMO

It is of great importance to understand the intrinsic relationship between phototautomerization and photoelectric properties for the exploration of novel organic materials. Here, in order to chemically control the protonation process, the aminated isoxazole derivative (2,2'-(isoxazolo[5,4-d]isoxazole-3,6-diyl)dibenzenaminium, DP-DA-DPIxz) with -N═ as the proton acceptor was designed to achieve the twisted intramolecular charge transfer (TICT) state which was triggered by an excited-state intramolecular proton transfer (ESIPT) process. This kind of protonation enhanced the intramolecular hydrogen bonding, conjugative effect, and steric hindrance effects, ensuring a barrierless spontaneous TICT process. Through the intramolecular proton transfer, the configuration torsion and conjugation dissociation of the DP-DA-DPIxz molecule was favored, which led to efficient charge separation and remarkable variations in light-emitting properties. We hope the present investigation will provide a new approach to design novel optoelectronic organic materials and shine light on the understanding of the charge transfer and separation process in molecular science.

6.
Nano Lett ; 23(5): 1726-1734, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36794942

RESUMO

Zn metal has received immense interest as a promising anode of rechargeable aqueous batteries for grid-scale energy storage. Nevertheless, the uncontrollable dendrite growth and surface parasitic reactions greatly retard its practical implementation. Herein, we demonstrate a seamless and multifunctional metal-organic framework (MOF) interphase for building corrosion-free and dendrite-free Zn anodes. The on-site coordinated MOF interphase with 3D open framework structure could function as a highly zincophilic mediator and ion sifter that synergistically induces fast and uniform Zn nucleation/deposition. In addition, the surface corrosion and hydrogen evolution are significantly suppressed by the interface shielding of the seamless interphase. An ultrastable Zn plating/stripping is achieved with elevated Coulombic efficiency of 99.2% over 1000 cycles and prolonged lifetime of 1100 h at 10 mA cm-2 with a high cumulative plated capacity of 5.5 Ah cm-2. Moreover, the modified Zn anode assures the MnO2-based full cells with superior rate and cycling performance.

7.
Angew Chem Int Ed Engl ; 63(15): e202400453, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38323751

RESUMO

Aggregation-induced emission (AIE) shows promising performance in chemical sensing relying on the change of the emission behavior of the probe molecule monomers to the aggregated product. However, whether the response contrast could be further boosted by utilizing the emission property of the aggregated probe and the aggregated product remains a big challenge. Here, an exciting AIE probe regulation strategy was proposed by coherently modulating the aggregation behavior and the intramolecular charge transfer (ICT) property of the probes and thus an aggregated-to-aggregated colorimetric-fluorescent dual-mode detection was achieved. The blue emissive film obtained with the optimal AIE probe has been proven to be effective to recognize the vapor of nerve agent analog DCP in air by emitting a sharp green fluorescence. In addition, a porous polymer-based wet sensing chip loaded with the probe enables the immediate response to DCP vapor with a limit of detection (LOD) of 1.7 ppb, and it was further integrated into a wearable watch device for long-term monitoring of DCP vapor up to two weeks. We expect the present probe design strategy would greatly deepen the AIE-based science and provide new insights for long-term monitoring sensors toward trace hazardous substances.


Assuntos
Corantes Fluorescentes , Agentes Neurotóxicos , Corantes Fluorescentes/química , Espectrometria de Fluorescência , Colorimetria
8.
Anal Chem ; 95(23): 9014-9024, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37260031

RESUMO

The precise regulation of the electron-withdrawing/electron-donating strength in a probe is of great significance for the design of reaction-based fluorescent probes with specific functionalities. Here, a family of excited-state intramolecular proton transfer (ESIPT)-based probes with fluorescence turn-on sensing properties toward KMnO4 was designed by precisely modulating the electron-withdrawing strength of the substituents located at the para-position of the recognition group. It is found that -F, -CHO, and -H as the electron-withdrawing groups bound at the probe can specifically recognize KMnO4, which ensures a blue emission displayed by the reaction products. Especially with -CHO as the electron-withdrawing group, the reaction product shows the most stable fluorescence. The probe 2-(benzo[d]oxazol-2-yl)-4-formylphenyl acrylate (BOPA-CHO) demonstrated a more superior sensing performance toward KMnO4, including a low limit of detection (LOD, 0.96 nM), a rapid response (<3 s), and a rather good selectivity even in the presence of 21 interferents. Moreover, the practicality of the probe was further verified by a test pen comprising a BOPA-CHO-embedded sponge, which is capable of detecting KMnO4 solid with a naked-eye LOD of 11.62 ng. The present probe design and modulation strategy would open up a new path for the design of high-performance fluorescent probes.

9.
Org Biomol Chem ; 21(2): 315-322, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36524697

RESUMO

A deep understanding of the fluorescence response mechanisms is the foundation for design-oriented strategies for D-π-A probes for trace hazardous chemicals. Here, from the perspective of electronegativity regulation of the π-bridge recognition site, an electron-donation modulation strategy involving various comprehensive evaluations of the optical and chemical properties is proposed through a series of theoretical analyses. Due to the preferential combined interaction between the π-bridge recognition site and MnO4-, high electrophilic reactivity and feasible chemical reaction energy barrier, a high-performance filter paper chip and hydrogel chip for the detection of aqueous and air-suspended environmental KMnO4 was achieved. We expect the present modulation strategy will facilitate efficient fluorescent probe design and provide a universal methodology for the exploration of functional D-π-A molecules.


Assuntos
Elétrons , Corantes Fluorescentes , Corantes Fluorescentes/química , Teoria da Densidade Funcional , Fluorescência
10.
J Phys Chem A ; 127(4): 902-912, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36669096

RESUMO

The exploration of the intrinsic relationship between the phototautomerization and photoelectric properties is of great significance for the application of the emerging novel organic materials, such as the (bi)heterocyclic thiazolo[5,4-d]thiazole derivatives (TzTz). Here, by introducing the chemical-controlling protonation, a barrierless spontaneous rotation movement of the designed TzTz derivative (2,5-diyl-amino-thiazolo[5,4-d]thiazole, DA-TzTz) was ensured through the facilitation of the excited-state intramolecular proton transfer (ESIPT) triggered twisted intramolecular charge transfer (TICT) process by the enhancement of the intramolecular hydrogen bonds, steric hindrance effect, and conjugative effect. It is further verified that the hetero S atoms could mostly effect the proton accepting ability of -N═ through comparing with the influences to the intramolecular H-bond between the protonated/nonprotonated amino groups and the -N═ atoms brought by the replacement of them with N or O atoms. As a result, the dissociation and rearrangement of the π conjugation in DA-TzTz accompanying with the variation of the optoelectronic characteristics was benefited from the establishment of the preferential charge-transfer and separation. We expect this tentative study could establish a new concept of designing an efficient charge-transfer and separation method, paving the way for the development of the TzTz derivatives and other optoelectronic organic materials.

11.
Surg Endosc ; 37(1): 518-527, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36002683

RESUMO

BACKGROUND: It is important to identify gallbladder polyps (GPs) with malignant potential and avoid unnecessary cholecystectomy by constructing prediction model. The aim of the study is to develop a Bayesian network (BN) prediction model for GPs with malignant potential in a long diameter of 8-15 mm based on preoperative ultrasound. METHODS: The independent risk factors for GPs with malignant potential were screened by χ2 test and Logistic regression model. Prediction model was established and validated using data from 1296 patients with GPs who underwent cholecystectomy from January 2015 to December 2019 at 11 tertiary hospitals in China. A BN model was established based on the independent risk variables. RESULTS: Independent risk factors for GPs with malignant potential included age, number of polyps, polyp size (long diameter), polyp size (short diameter), and fundus. The BN prediction model identified relationships between polyp size (long diameter) and three other variables [polyp size (short diameter), fundus and number of polyps]. Each variable was assigned scores under different status and the probabilities of GPs with malignant potential were classified as [0-0.2), [0.2-0.5), [0.5-0.8) and [0.8-1] according to the total points of [- 337, - 234], [- 197, - 145], [- 123, - 108], and [- 62,500], respectively. The AUC was 77.38% and 75.13%, and the model accuracy was 75.58% and 80.47% for the BN model in the training set and testing set, respectively. CONCLUSION: A BN prediction model was accurate and practical for predicting GPs with malignant potential patients in a long diameter of 8-15 mm undergoing cholecystectomy based on preoperative ultrasound.


Assuntos
Doenças da Vesícula Biliar , Neoplasias da Vesícula Biliar , Pólipos , Humanos , Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/patologia , Teorema de Bayes , Doenças da Vesícula Biliar/cirurgia , Colecistectomia , Ultrassonografia , Pólipos/diagnóstico por imagem , Pólipos/cirurgia , Pólipos/patologia , Estudos Retrospectivos
12.
Surg Endosc ; 37(7): 5453-5463, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37041283

RESUMO

BACKGROUND: Polyp size of 10 mm is insufficient to discriminate neoplastic and non-neoplastic risk in patients with gallbladder polyps (GPs). The aim of the study is to develop a Bayesian network (BN) prediction model to identify neoplastic polyps and create more precise criteria for surgical indications in patients with GPs lager than 10 mm based on preoperative ultrasound features. METHODS: A BN prediction model was established and validated based on the independent risk variables using data from 759 patients with GPs who underwent cholecystectomy from January 2015 to August 2022 at 11 tertiary hospitals in China. The area under receiver operating characteristic curves (AUCs) were used to evaluate the predictive ability of the BN model and current guidelines, and Delong test was used to compare the AUCs. RESULTS: The mean values of polyp cross-sectional area (CSA), long, and short diameter of neoplastic polyps were higher than those of non-neoplastic polyps (P < 0.0001). Independent neoplastic risk factors for GPs included single polyp, polyp CSA ≥ 85 mm 2, fundus with broad base, and medium echogenicity. The accuracy of the BN model established based on the above independent variables was 81.88% and 82.35% in the training and testing sets, respectively. Delong test also showed that the AUCs of the BN model was better than that of JSHBPS, ESGAR, US-reported, and CCBS in training and testing sets, respectively (P < 0.05). CONCLUSION: A Bayesian network model was accurate and practical for predicting neoplastic risk in patients with gallbladder polyps larger than 10 mm based on preoperative ultrasound features.


Assuntos
Doenças da Vesícula Biliar , Neoplasias da Vesícula Biliar , Pólipos , Humanos , Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/patologia , Teorema de Bayes , Doenças da Vesícula Biliar/cirurgia , Ultrassonografia , Pólipos/diagnóstico por imagem , Pólipos/cirurgia , Pólipos/patologia , Estudos Retrospectivos
13.
Hepatobiliary Pancreat Dis Int ; 22(1): 28-33, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36210313

RESUMO

BACKGROUND: The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation (LT). Gastroduodenal artery (GDA) disconnection increased proper hepatic artery flow. Whether this procedure attenuates biliary non-anastomotic stricture (NAS) is not clear. METHODS: A total of 241 patients with LT were retrospectively analyzed. The patients were divided into the GDA disconnection (GDA-) and GDA preservation (GDA+) groups. Propensity score matching (PSM) was administrated to reduce bias. Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM. Postoperative complications were compared. Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival. RESULTS: In all, 99 patients (41.1%) underwent GDA disconnection, and 49 (20.3%) developed NAS. Multivariate logistic regression revealed that GDA preservation (OR = 2.24, 95% CI: 1.11-4.53; P = 0.025) and model for end-stage liver disease (MELD) score > 15 (OR = 2.14, 95% CI: 1.12-4.11; P = 0.022) were risk factors for biliary NAS. PSM provided 66 pairs using 1:2 matching method, including 66 GDA disconnection and 99 GDA preservation patients. Multivariate logistic regression after PSM also showed that GDA preservation (OR = 3.15, 95% CI: 1.26-7.89; P = 0.014) and MELD score > 15 (OR = 2.41, 95% CI: 1.08-5.36; P = 0.031) were risk factors for NAS. When comparing complications between the two groups, GDA preservation was associated with a higher incidence of biliary NAS before and after PSM (P = 0.031 and 0.017, respectively). In contrast, other complications including early allograft dysfunction (P = 0.620), small-for-size graft syndrome (P = 0.441), abdominal hemorrhage (P = 1.000), major complications (Clavien-Dindo grade ≥ 3, P = 0.318), and overall survival (P = 0.088) were not significantly different between the two groups. CONCLUSIONS: GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.


Assuntos
Constrição Patológica , Artéria Hepática , Transplante de Fígado , Humanos , Constrição Patológica/epidemiologia , Constrição Patológica/prevenção & controle , Doença Hepática Terminal/cirurgia , Artéria Hepática/cirurgia , Incidência , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Fatores de Risco
14.
Entropy (Basel) ; 25(4)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37190401

RESUMO

In this paper, the major problems associated with detached eddy simulation (DES) (namely, modeled stress depletion (MSD) and slowing of the RANS to LES transition (RLT)) are discussed and reviewed, and relevant improvements are developed. A modified version for the delayed DES (DDES) method with adaptive modified adequate shielding and rapid transition is proposed; this is called MSRT DDES. The modified shielding strategy can be adjusted adaptively according to the local flow conditions: keeping the RANS behavior in the whole boundary layer when there is no resolved turbulence, and weakening the shielding function when resolved turbulence exists in the mainstream over the boundary layer. This strategy can significantly ameliorate the MSD in the RANS boundary layer, regardless of the mesh refinement, and avoid excessive shielding in the fully developed resolved turbulence that may otherwise delay the development of the separated and reattached flow. Three cases are designed to test the modified DDES, namely, complete shielding in the RANS zone of a boundary layer (the zero-pressure gradient turbulent boundary layer with the refined mesh), modified adaptive improved shielding with a rapid transition (the flow over a hump), and the overall performance in a complex 3D separation (the corner separation in a compressor cascade). The results show that the modified shielding function is more physical than earlier proposals compared to shielding functions, and according to detailed comparisons of the wall skin friction coefficients, velocity profiles, total pressure-loss coefficients, entropy production analyses, and so on, the MSD and RLT problems are moderately alleviated by the MSRT DDES.

15.
Anal Chem ; 94(25): 9184-9192, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35713422

RESUMO

Although a set of functional molecules with the D-π-A structure has been explored as optical probes for the detection of target analytes, it remains a great challenge to elaborately design a single probe for distinguishing different analytes by their intrinsic oxidation or reduction capabilities and thus to generate distinct optical responses. Here, a unique TCF-based probe (DMA-CN) containing two unsaturated double bonds in the π-conjugation bridge and TCF with different reaction activities that could be cut off by KMnO4 and NaClO in varying degrees was developed, causing remarkably distinguishable responses for both fluorescence and colorimetric channels to discriminate KMnO4 and NaClO from each other. The fluorescence and colorimetric limits of detection (LODs) of the proposed DMA-CN toward KMnO4 were calculated as 60 and 91 nM, respectively, while those for NaClO were 13.3 and 214 nM, and all the optical signal change can be observed within 1 s with good specificity. Based on the proposed probe design strategy, a well-fabricated test strip was proven to be promising for the rapid, in-field detection and risk management. We expect that the present probe design methodology would provide a powerful strategy for efficient probe exploration, especially for discriminating the substances with similar oxidizing properties.


Assuntos
Colorimetria , Oxidantes , Colorimetria/métodos , Limite de Detecção , Oxirredução
16.
Anal Chem ; 94(16): 6318-6328, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35427131

RESUMO

Achieving sensitive and robust colorimetry is of great significance for on-site chemical detection, but has always been a dilemma or at the expense of practicality. Here, from the perspective of solvent, which is commonly the indispensable medium for chemical sensing, the solvent induction strategy concerning the hydrophobic shielding and hydrophilic bonding solvent cage was proposed considering the configuration branching ratio in the reagent and the prevention of the autoxidation channel. Due to the competitive delocalized charge transfer in the probe and the effective viscous drag in the reagent, remarkable sensing signal concentrating and moisture retention capability were achieved. We expect the present strategy would facilitate the active but robust chemical reaction design and provide a universal methodology for the exploration of high-performance chemical sensors.


Assuntos
Colorimetria , Ureia , Colorimetria/métodos , Solventes
17.
Anal Chem ; 94(33): 11679-11687, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35948453

RESUMO

Inhibition of twisting intramolecular charge transfer (TICT) is one of the most attractive methods for fluorescence-on analysis, whereas it remains enigmatic whether the fluorescence in a TICT-based probe could be thoroughly lightened. Here, for maximizing the fluorescence-on signal of the TICT-based probe, we develop a model by employing chemical reaction to directly cleave the linkage between the rotational electron donor and acceptor with a predisposed fluorescent signal close to zero. To validate this assumption, a nonfluorescent probe with barrierless rotation is successfully achieved by grafting acryloyl with -C═C- recognition sites onto coumarin, and 7-hydroxycoumarin with bright blue fluorescence could be released within 3 s upon probing KMnO4 with an amount as low as 0.95 nM and 6.6 pg. We believe that the present strategy could not only deepen the insights of photochemistry but also facilitate the development of a theranostic drug delivery system, energy conversion, pollution control, and health risk reduction.


Assuntos
Corantes , Fluorescência , Fotoquímica , Rotação
18.
Sensors (Basel) ; 23(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36617037

RESUMO

Airborne transient electromagnetic (ATEM) technology is a technique often used in mineral exploration and geological mapping. Due to inductive polarization (IP) phenomena, the ATEM response curve often shows a negative response or declines rapidly to the attenuation curve. Traditional resistivity inversion techniques do not explain the IP response of a signal well, so the negative response is usually removed during data processing, resulting in a reduced correctness and authenticity of the findings. In this paper, in the parameter inversion based on the Cole-Cole model, the Jacobian matrix chain analysis method is used to calculate, and the current waveform calculation is also considered in the inversion. The results show that compared with the perturbation method, the analysis technique can greatly reduce the calculation time and improve the inversion efficiency. In the single-point one-dimensional inversion and lateral constraint quasi-two-dimensional inversion, the Cole-Cole four-parameter forward response has strong inversion accuracy, which can successfully invert the actual exploration content and the Cole-Cole four-parameter response. Some measured sounding data in the Qingchengzi survey area of Liaoning Province, China have a negative response to IP, and the resistivity scheme cannot be used alone for inversion, but the real underground resistivity structure can be obtained through the method studied in this paper, and good exploration results can be obtained.

19.
Angew Chem Int Ed Engl ; 61(29): e202203358, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363416

RESUMO

Manipulation of a multi-physical quantity to steer a molecular photophysical property is of great significance in improving sensing performance. Here, an investigation on how a physical quantity rooted in the molecular structure induces an optical behavior change to facilitate ultrasensitive detection of ethylenediamine (EDA) is performed by varying a set of thiols. The model molecule consisting of a thiol with dual-carboxyl exhibits the strongest fluorescence, which is ascribed to the electron-donating ability and prompted larger orbital overlap and oscillator strength. The elevated fluorescence positively corelated to the increased EDA, endowing an ultrasensitive response to the nanomolar-liquid/ppm-vapor. A gas detector with superior performance fulfills a contactless and real-time management of EDA. We envisage this electron-tuning strategy-enabled fluorescence enhancement can offer in-depth insight in advancing molecule-customized design, further paving the way to widening applications.


Assuntos
Corantes , Etilenodiaminas , Eletrônica , Etilenodiaminas/química , Espectrometria de Fluorescência , Compostos de Sulfidrila
20.
J Hepatol ; 74(1): 96-108, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738450

RESUMO

BACKGROUND & AIMS: p53 mutations occur frequently in human HCC. Activation of the mammalian target of rapamycin (mTOR) pathway is also associated with HCC. However, it is still unknown whether these changes together initiate HCC and can be targeted as a potential therapeutic strategy. METHODS: We generated mouse models in which mTOR was hyperactivated by loss of tuberous sclerosis complex 1 (Tsc1) with or without p53 haplodeficiency. Primary cells were isolated from mouse livers. Oncogenic signalling was assessed in vitro and in vivo, with or without targeted inhibition of a single molecule or multiple molecules. Transcriptional profiling was used to identify biomarkers predictive of HCC. Human HCC materials were used to corroborate the findings from mouse models. RESULTS: p53 haploinsufficiency facilitates mTOR signalling via the PTEN/PI3K/Akt axis, promoting HCC tumorigenesis and lung metastasis. Inhibition of PI3K/Akt reduced mTOR activity, which effectively enhanced the anticancer effort of an mTOR inhibitor. ATP-binding cassette subfamily C member 4 (Abcc4) was found to be responsible for p53 haploinsufficiency- and Tsc1 loss-driven HCC tumorigenesis. Moreover, in clinical HCC samples, Abcc4 was specifically identified an aggressive subtype. The mTOR inhibitor rapamycin significantly reduced hepatocarcinogenesis triggered by Tsc1 loss and p53 haploinsufficiency in vivo, as well as the biomarker Abcc4. CONCLUSIONS: Our data advance the current understanding of the activation of the PTEN/PI3K/Akt/mTOR axis and its downstream target Abcc4 in hepatocarcinogenesis driven by p53 reduction and Tsc1 loss. Targeting mTOR, an unexpected vulnerability in p53 (haplo)deficiency HCC, can be exploited therapeutically to treat Abcc4-positive patients with HCC. LAY SUMMARY: Tsc1 loss facilitates the p53 (haplo)insufficiency-mediated activation of the PTEN/Akt/mTOR axis, leading to the elevated expression of Abcc4 to drive HCC tumorigenesis and metastasis in mice. Inhibition of mTOR protects against p53 haploinsufficiency and Tsc1 loss-triggered tumour-promoting activity, providing a new approach for treating an aggressive subtype of HCC exhibiting high Abcc4 expression.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Pirazóis/farmacologia , Pirimidinas/farmacologia , Serina-Treonina Quinases TOR/genética , Proteína Supressora de Tumor p53/genética , Animais , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Haploinsuficiência/efeitos dos fármacos , Haploinsuficiência/genética , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Inibidores de MTOR/farmacologia , Camundongos , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Proteína 1 do Complexo Esclerose Tuberosa/genética
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