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Hydrogen sulfide (H2S), a critical gas signaling molecule, and N-acetyltransferase 2 (NAT2), a key enzyme in drug metabolism, are both known active biomarkers for liver function. However, the interactions and effects of H2S and NAT2 in living cells or lesion sites remain unknown due to the lack of imaging tools to achieve simultaneous detection of these two substances, making it challenging to implement real-time imaging and precise tracking. Herein, we report an activity-based two-photon fluorescent probe, TPSP-1, for the cascade detection of H2S and NAT2 in living liver cells. Continuous conversion from TPSP-1 to TPSP-3 was achieved in liver cells and tissues. Significantly, leveraging the outstanding optical properties of this two-photon fluorescent probe, TPSP-1, has been effectively used to identify pathological tissue samples directly from clinical liver cancer patients. This work provides us with this novel sensing and two-photon imaging probe, which can be used as a powerful tool to study the physiological functions of H2S and NAT2 and will help facilitate rapid and accurate diagnosis and therapeutic evaluation of hepatocellular carcinoma.
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Arilamina N-Acetiltransferase , Carcinoma Hepatocelular , Corantes Fluorescentes , Sulfeto de Hidrogênio , Neoplasias Hepáticas , Fótons , Sulfeto de Hidrogênio/análise , Sulfeto de Hidrogênio/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Humanos , Arilamina N-Acetiltransferase/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Animais , Camundongos , Células Hep G2 , Imagem ÓpticaRESUMO
A new efficient method for considering the long-range effect of reactive scattering processes in ultra-cold conditions has been developed using the time-dependent quantum wave packet theory, where the initial wave packet could be placed at a position near the interaction region. This is in contrast to previous methods, where the initial wave packet has to be placed far from the interaction region. The new method reduces the numerical effort significantly. Typical reactions, such as S(1D) + H2, D+ + H2, and 7Li + 7Li2 (v0 = 1, j0 = 0), under cold or ultra-cold conditions, are used to demonstrate the numerical efficiency of the new method.
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In this work, using the time-dependent quantum wave packet method, quite a few typical higher-order split operators (HOSOs) were for the first time applied to calculate the tetratomic reactive scattering processes in the hyperspherical coordinate. It was found that the HOSOs were hardly efficient for a tetratomic reaction calculation, unlike those for a triatomic reactive scattering calculation. We proposed an efficient HOSO with a force gradient (denoted as 2G1 in the main text) for efficiently and accurately calculating a tetratomic reaction using the quantum wave packet method. Several typical tetratomic reactions, such as H2 + OH, HF + OH, and H2 + OH+, are calculated for demonstrating the effectiveness of the proposed 2G1 in terms of (product state-resolved) reaction probability and inelastic probability, by comparing with the performance of the previously reported various HOSOs. We suggest that the 2G1 propagator could be applied to efficiently calculate a general tetratomic reaction.
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The typical hydrogen atom plus halogen molecule reaction H + Cl2 â HCl + Cl has implications across many fields. In this paper, product state-resolved quantum dynamics calculations for the vibrationally excited reaction H + Cl2 (v0 = 1-3, j0 = 0) â HCl + Cl were conducted using the time-dependent wave packet method on a newly developed accurate potential energy surface. Numerical results indicate that the initial vibrational excitation of Cl2 does enhance the reactivity for this early barrier reaction, although less than the enhancement of the translational energy. The calculated product vibrational state-resolved integral cross sections and rate constants reveal that the product vibrational state distribution and the initial vibrational state of Cl2 are highly correlated. The thermal rate constant in the temperature range from 100 to 1000 K was given and is found to be in reasonable agreement with the experimental measurements.
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The interaction-asymptotic region decomposition (IARD) technique has been proven to be a good solution to the long-standing coordinate problem in reactive scattering calculations. In this work, the IARD technique was further developed using Jacobi coordinates for the interaction region, instead of the previously used hyperspherical coordinates. Although the Jacobi coordinate may not be as optimal as the hyperspherical coordinates for describing the interaction region in reactive scattering processes, it has simpler kinetic operators and provides a more physically intuitive picture. By developing an intermediate interpolation method, which could efficiently transform the overlapped wave functions from the asymptotic regions to the interaction region, the new implementation of the IARD technique for triatomic reactive scatterings is similarly efficient and accurate. The differential cross sections of the H+H2, and product state-resolved reaction probabilities of the F+HD and16O+36O2 reactions, which involve products of extremely low translational energy and are challenging for a single coordinate-based method, were calculated as numerical examples to show the ability of the new method.
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The reaction of H + Cl2 â HCl + Cl plays a crucial role in various fields. However, no previous study has investigated this reaction using accurate quantum mechanical methods. In this paper, we construct a global potential energy surface (PES) using the neural network method with more than 20,000 ab initio energies obtained by the MRCI-F12+Q method with the aug-cc-pV5Z basis and extrapolated to the complete basis set limit. The spin-orbit coupling of the Cl atom has been considered in the PES. With this new PES, product state-resolved quantum dynamics calculations for the H + Cl2 (v0 = 0, j0 = 0-2) â HCl + Cl reaction was carried out. Numerical results show that the initial rotational excitation of the Cl2 has negligible effects on the reactivity. Product state-resolved integral cross sections (ICS) and rate constants reveal that the HCl is most favorably produced in its v' = 2 vibrational state. The calculated product vibrational state-resolved and total reaction rate constants suggest that the new global PES is accurate enough, as compared with the available experimental measurements.
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New global diabatic potential energy surfaces (DPESs) for the ground (12A') and first excited (22A') states for the Li + H2 system were developed, with more than 30,000 energy points at the IC-MRCI+Q level of theory, utilizing the aug-cc-pV5Z basis set for the H atoms and the cc-pCV5Z basis set for the Li atom, fitted by a single neural network (NN) with symmetry. Product state-resolved quantum dynamics calculations of the nonadiabatic reaction Li (2P) + H2 (X 1 ∑g+, v0 = 0, j0 = 0) â LiH (X 1∑+) + H(2S) were carried out using these new DPESs and also the previous HYLC-DPESs. The numerical results suggested that our newly constructed DPESs provided an accurate description of the LiH2 system.
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Although the reactant-product decoupling (RPD) technique was proposed over two decades ago, it remains an efficient approach for calculating product state-resolved information on some simple direct reactions using the quantum wave packet method. In the past, usually the RPD technique employed the collocation method to transform the wave function between reactant and product arrangements, which requires quite large computational efforts. In this work, the intermediate coordinate (IC) method is employed to realize the RPD technique. Numerical examples demonstrate that this new IC RPD (IRPD) technique has superior computational efficiency compared with the original method employing the collocation method. Especially, the new IRPD technique significantly saves disk space and computer memory. To illustrate the features of our new method, the total reaction probabilities of the H + H2, H + Br2, and F + H2 reactions with J = 0 and the differential cross sections of the H + H2 and F + H2 reactions at a series of collision energy are calculated and presented. With this efficient and effective new RPD technique, the Li + HF reaction, which involves sharp resonances with long-range wave functions in the van der Waals wells in both the reactant and product arrangements, is also calculated with several J at the product state-resolved level to reveal the ability of the RPD technique for describing resonance wave functions. With these numerical examples, it is found that, for the reaction with resonances, the RPD approach should be applied carefully. Otherwise, it is very possible that the resonances could disappear with the application of the RPD technique.
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The impact of non-Born-Oppenheimer couplings on the isotopic effects in the reaction of the Cl(2P) atom with the HD (v = 0, j = 0) molecule is investigated with our recently developed nonadiabatic time-independent quantum scattering methods, where the full open-shell characteristics are included in the six-state model, and also with the recently developed two-state model solving by time-independent methods, where part of the open-shell characteristic is included. The same reaction is also calculated with the simple adiabatic model using the lowest adiabatic potential energy surface. Compared with the results from different models, it is found that the reactivity of the Cl + HD â HCl + D channel is significantly overestimated in the adiabatic model. In contrast, the reactivity of the other channel agrees well with the nonadiabatic models. This is due to the van der Waals well in the reactant channel being changed a lot by including the nonadiabatic couplings. These quantum dynamics calculations suggest that sometimes the adiabatic model should be used with caution; otherwise, it may result in significant deviations for some reactions.
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This corrects the article DOI: 10.1038/nature23667.
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The ability to control chemical and physical structuring at the nanometre scale is important for developing high-performance thermoelectric materials. Progress in this area has been achieved mainly by enhancing phonon scattering and consequently decreasing the thermal conductivity of the lattice through the design of either interface structures at nanometre or mesoscopic length scales or multiscale hierarchical architectures. A nanostructuring approach that enables electron transport as well as phonon transport to be manipulated could potentially lead to further enhancements in thermoelectric performance. Here we show that by embedding nanoparticles of a soft magnetic material in a thermoelectric matrix we achieve dual control of phonon- and electron-transport properties. The properties of the nanoparticles-in particular, their superparamagnetic behaviour (in which the nanoparticles can be magnetized similarly to a paramagnet under an external magnetic field)-lead to three kinds of thermoelectromagnetic effect: charge transfer from the magnetic inclusions to the matrix; multiple scattering of electrons by superparamagnetic fluctuations; and enhanced phonon scattering as a result of both the magnetic fluctuations and the nanostructures themselves. We show that together these effects can effectively manipulate electron and phonon transport at nanometre and mesoscopic length scales and thereby improve the thermoelectric performance of the resulting nanocomposites.
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BACKGROUND: Endostar is a strong angiogenesis inhibitor that is effective in treating non-small cell lung cancer (NSCLC), but the effect of Endostar in the treatment of patients with EGFR-TKI-resistant NSCLC remains unclear. We evaluated the clinical efficacy and safety of Endostar in EGFR-mutant NSCLC patients resistant to EGFR inhibition treatment. METHODS: From January 1, 2016 to June 30, 2018, 68 patients were selected from the 4 institutions for the study. Patients with NSCLC received Endostar plus chemotherapy every 21-day cycle. Chemotherapy types included platinum-containing dual drugs and platinum-free single drugs. Endostar was administered by intermittent intravenous infusion or continuous microinfusion pump infusion. The overall response rate (ORR), disease control rate (DCR) and adverse events were analyzed. Survival of patients was also evaluated. RESULTS: For all patients, the median progression-free survival (PFS) was 2.8 months, and the median overall survival (OS) was 14.2 months. PFS and OS in the Endostar pump continuous group were better than those in the Endostar intravenous infusion group. The disease control rate (DCR) was 79.4%. A total of 28 (41.2%) patients experienced varying grades of adverse events during treatment. No treatment-associated deaths were observed. The grade 3 treatment-emergent adverse events (TEAEs) were myelosuppression, weakness, and nausea/vomiting. CONCLUSIONS: Endostar was effective and well tolerated in advanced NSCLC patients. Endostar treatment showed promising survival results in EGFR-mutant NSCLC patients.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Estudos Retrospectivos , Receptores ErbB/genética , Inibidores de Proteínas Quinases/efeitos adversos , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
BACKGROUND: High-grade squamous intraepithelial lesion (HSIL) is a disease that is closely related to the development of cervical cancer. In clinical work, cold knife conization and a loop electrosurgical excision procedure (LEEP) are often selected for diagnosis and treatment. OBJECTIVE: In this paper, we aimed to discuss additional cuts, a common practice in cervical conization, and determine whether the doctor's choice to use additional cuts in conization can reduce the occurrence of a positive cone margin. METHODS: From January 2018 to October 2019, 965 patients underwent cervical conization at the First Affiliated Hospital of Dalian Medical University (Dalian, China). Of these, 174 were in the positive cone margin group, and 791 were in the negative cone margin group. Age, preoperative pathology, pathological results of conization, additional cuts, cone depth, and cone volume were studied. Additionally, the additional cut rate and the efficiency of doctors with a habit of additional cuts were analyzed. RESULTS: Of the 965 patients included in the study, the median age was 41 years (range 35-50). Multivariable logistic regression analysis suggested that additional cuts (OR, 2.480; 95% CI 1.608 to 3.826; p = 0.01) and smaller cone depth (OR, 0.591; 95% CI, 0.362 to 0.965, p = 0.036) were independent risk factors for positive margins. Six of the 64 doctors who performed conizations had a habit of making additional cuts, and there was no positive correlation between their additional cut rate and their effective additional cut rate. CONCLUSION: This study showed that a certain proportion of additional cuts can be effectively excised from the positive margin that cannot be removed in the initial conization. The practice of additional cuts in conization tends to be the personal habit of a small number of doctors.
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Carcinoma in Situ , Carcinoma de Células Escamosas , Humanos , Adulto , Pessoa de Meia-Idade , Conização , China , HospitaisRESUMO
BACKGROUND: This meta-analysis was conducted to systematically evaluate the impact of problem-based learning (PBL) and lecture-based learning (LBL) teaching models on students' learning in surgical education. METHODS: We systematically searched the publications related to the application of PBL and LBL in surgical courses in PubMed, Embase, Web of Science and Cochrane Library databases, the last retrieval time is September 20, 2022. After screening the literature according to the inclusion and exclusion criteria, extracting data and evaluating the methodological treatment of the included studies, Stata 17.0 software was used to perform meta-analysis. RESULTS: Nine studies were included totally. The results showed that compared with LBL, PBL was superior in clinical competence (SMD = 0.81, 95% CI: 0.12 ~ 1.49, P = 0.020) and student satisfaction (SMD = 2.13, 95% CI: 1.11 ~ 3.15, P < 0.0001) with significant differences. But the comprehensive scores (SMD = 0.26, 95% CI: -0.37 ~ 0.89, P = 0.421) and theoretical knowledge (SMD=-0.19, 95% CI: -0.71 ~ 0.33, P = 0.482) to PBL and LBL had no significant difference. CONCLUSION: This study showed that the PBL teaching model is more effective than the LBL teaching model in surgical education on the aspects of enhancing clinical competence and student satisfaction. However, further well-designed studies are needed to confirm our findings.
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Educação Médica , Aprendizagem Baseada em Problemas , Humanos , Aprendizagem Baseada em Problemas/métodos , Avaliação Educacional , Estudantes , Educação Médica/métodos , Competência ClínicaRESUMO
The Cyclone Global Navigation Satellite System (CYGNSS), a publicly accessible spaceborne Global Navigation Satellite System Reflectometry (GNSS-R) data, provides a new alternative opportunity for large-scale soil moisture (SM) retrieval, but with interference from complex environmental conditions (i.e., vegetation cover and ground roughness). This study aims to develop a high-accuracy model for CYGNSS SM retrieval. The normalized surface reflectivity calculated by CYGNSS is fused with variables that are highly related to the SM obtained from optical/microwave remote sensing to solve the problem of the influence of complicated environmental conditions. The Gradient Boost Regression Tree (GBRT) model aided by land-type data is then used to construct a multi-variables SM retrieval model with six different land types of multiple models. The methodology is tested in southeastern China, and the results correlate very well with the existing satellite remote sensing products and in situ SM data (R = 0.765, ubRMSE = 0.054 m3m-3 vs. SMAP; R = 0.653, ubRMSE = 0.057 m3 m-3 vs. ERA5 SM; R = 0.691, ubRMSE = 0.057 m3m-3 vs. in situ SM). This study makes contributions from two aspects: (1) improves the accuracy of the CYGNSS retrieval of SM based on fusion with other auxiliary data; (2) constructs the SM retrieval model with multi-layer multiple models, which is suitable for different land properties.
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For the existing visual-inertial SLAM algorithm, when the robot is moving at a constant speed or purely rotating and encounters scenes with insufficient visual features, problems of low accuracy and poor robustness arise. Aiming to solve the problems of low accuracy and robustness of the visual inertial SLAM algorithm, a tightly coupled vision-IMU-2D lidar odometry (VILO) algorithm is proposed. Firstly, low-cost 2D lidar observations and visual-inertial observations are fused in a tightly coupled manner. Secondly, the low-cost 2D lidar odometry model is used to derive the Jacobian matrix of the lidar residual with respect to the state variable to be estimated, and the residual constraint equation of the vision-IMU-2D lidar is constructed. Thirdly, the nonlinear solution method is used to obtain the optimal robot pose, which solves the problem of how to fuse 2D lidar observations with visual-inertial information in a tightly coupled manner. The results show that the algorithm still has reliable pose-estimation accuracy and robustness in many special environments, and the position error and yaw angle error are greatly reduced. Our research improves the accuracy and robustness of the multi-sensor fusion SLAM algorithm.
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Ecological restoration practices have been widely adopted to increase soil carbon stocks by improving soil organic carbon (SOC). However, the effects of these practices on the other important soil carbon component, soil inorganic carbon (SIC), remain unclear. To address this, a meta-analysis based on 45 publications and 37 sites was conducted to quantitatively assess the dynamic changes in SIC stocks due to typical restoration practices, including conversion of cropland to forest (C-F), cropland to grassland (C-G), desert to cropland (D-C), conservation agriculture (CA), and desert to forest (D-F). Results showed that, among the restoration practices increasing the SOC stocks, the SIC stocks decreased after the C-F (-34.7%) and C-G (-15.8%) conversions and CA (-6.8%), but increased after the conversion of D-C (2.6%) and D-F (46.9%). Additionally, in terms of recovery duration, the negative effect of C-G on SIC stocks may vanish with increased recovery duration, whereas SIC stocks showed a prominent increase initially after CA and then decreased over time; the response to D-F conversion of SIC stocks remained consistently positive over time. Furthermore, the non-synergistic changes with SIC and SOC could be due to variations in edaphic factors, while the effects edaphic factors on SIC stocks were different under various ecological restoration practices. Among all the impact factors, mean annual temperature, initial SIC stocks, and types of ecological restoration practice, were the most crucial factors explaining the variation in SIC stocks with ecological restoration. Collectively, the results highlight that the change in SIC stocks is asynchronous with the increase in SOC stocks in space and time after ecological restoration, further indicating that changes in SIC stocks should be paid more attention when assessing and predicting carbon sequestration following various ecological restoration practices.
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Carbono , Solo , Agricultura/métodos , Florestas , Sequestro de CarbonoRESUMO
BACKGROUND: N6-methyladenosine (m6A) is a dynamic and reversible internal RNA structure of eukaryotic mRNA. YTH domain family 2 (YTHDF2), an m6A-specific reader YTH domain family, plays fundamental roles in several types of cancer. However, the function of YTHDF2 in lung squamous cell carcinoma (LUSC) remains elusive. METHODS: The knockdown and overexpression of YTHDF2 in LUSC cells were conducted to detect the biological characteristics of YTHDF2. In vivo assays, the role of YTHDF2 in tumor growth was further uncovered. In vitro assays, YTHDF2 was confirmed to be involved in activating the mTOR/AKT signaling and YTHDF2 overexpression induced the EMT process in LUSC. Clinically, immunohistochemical staining revealed the relationship between YTHDF2 expression levels and the clinicopathological characteristics of lung squamous cell carcinoma patients. Moreover, quantitative PCR (qPCR), western blot, CCK8 assay, transwell assay, and wound-healing assay were used to detect the expression level and function of YTHDF2 under hypoxia exposure in LUSC cells. RESULTS: The results showed that hypoxia-mediated YTHDF2 overexpression promotes cell proliferation and invasion by activating the mTOR/AKT axis, and YTHDF2 overexpression induces the EMT process in LUSC. Moreover, YTHDF2 is closely associated with pN (pN- 37.0%, pN + 73.9%; P = 0.002) and pTNM stage (pI 50.0%, PII 43.3%, pIIIa 80.6%; P = 0.007), ultimately resulting in poor survival for LUSC patients. CONCLUSION: In brief, the results highlight high-YTHDF2 expression predicted a worse prognosis of LUSC, while hypoxia-mediated YTHDF2 overexpression promotes lung squamous cell carcinoma progression by activation of the mTOR/AKT signaling pathway.
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Lung cancer remains one of the major causes of cancer-related death globally. Recent studies have shown that aberrant m6A levels caused by METTL3 are involved in the malignant progression of various tumors, including lung cancer. The m6A modification, the most abundant RNA chemical modification, regulates RNA stabilization, splicing, translation, decay, and nuclear export. The methyltransferase complex plays a key role in the occurrence and development of many tumors by installing m6A modification. In this complex, METTL3 is the first identified methyltransferase, which is also the major catalytic enzyme. Recent findings have revealed that METTL3 is remarkably associated with different aspects of lung cancer progression, influencing the prognosis of patients. In this review, we will focus on the underlying mechanism of METT3 in lung cancer and predict the future work and potential clinical application of targeting METTL3 for lung cancer therapy.
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As the most common endocrine-related malignant tumor, the prevalence of thyroid cancer (TC) has soared strikingly over the past thirty years then verged to stabilization or even descension temporally. Distributed in a cell-specific manner, circular RNAs (circRNAs) is a novel class of non-coding RNAs characterized by its covalently closed loop without 5'-terminal cap and 3'-terminal poly A tail, which guarantee its distinctive evolutionary conservation and exonucleases resistance. Emerging evidence indicates that circRNA participates in the pathogenesis and carcinogenesis of several cancers including thyroid cancer. In this review, we concentrated on the connection between circRNAs and thyroid cancer so as to obtain a more profound understanding. We aim to discuss this relationship between TC and circRNAs by summarizing the effect of various circRNAs on tumor biological behaviors and clinical application, and systematically outlook the conceivable application of circRNAs in TC diagnosis and therapy.