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1.
J Chem Phys ; 161(5)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39092942

RESUMO

Conical intersections (CIs) play a crucial role in photochemical reactions, offering an efficient channel for ultrafast non-adiabatic relaxation of excited states. This significantly influences the reaction pathways and the resulting products. In this work, we utilize the non-Markovian stochastic Schrödinger equation with complex modes method to explore the dynamics of electronic transitions through conical intersections (CIs) in pyrazine. The linear vibronic coupling model serves as the foundational framework, incorporating both intra-state and inter-state electron-vibrational interactions. The dynamics of the excited electronic transitions are analyzed across varying strengths of system-bath coupling and different bath relaxation times. The accuracy of this method is demonstrated by comparing its predictions with those from the hierarchical equations of motion method.

2.
Nutr Cancer ; 71(6): 1007-1018, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31032633

RESUMO

Resistance to chemotherapy drugs, such as adriamycin (ADR), is a common problem in acute myeloid leukemia (AML) patients. We hypothesized that the natural compound resveratrol (Res) may reverse AML drug resistance through the PI3K/Akt/Nrf2 pathway. We investigated the in vitro effect of Res using human promyelocytic leukemia cells (HL-60) and the ADR-resistant cell line (HL-60/ADR) and treated with either Res or ADR + Res. Cellular proliferation inhibition rate, auto-fluorescence intensity of ADR in HL-60/ADR cells and HL-60 cells, mRNA expression of Nrf2 and the drug-resistant gene MRP1, and protein expression of PI3K, Akt, p-Akt, Nrf2, and MRP1 were measured. Results showed ADR + Res had a more significant inhibitory effect than ADR alone on HL-60/ADR cells. Auto-fluorescence intensity of ADR in HL-60/ADR cells treated with ADR + Res significantly increased. No difference of the auto-fluorescence intensity of ADR was observed in HL-60 cells treated with ADR and ADR + Res. mRNA expression of Nrf2 and MRP1 significantly decreased in HL-60/ADR cells treated with both Res and ADR + Res; protein expression of PI3K, p-Akt, Nrf2, and MRP1 significantly decreased in HL-60/ADR cells treated with PI3K inhibitor, Res and ADR + Res. In conclusion, Res reverses the drug resistance of AML HL-60/ADR cells through regulation of the PI3K/Akt/Nrf2 signaling pathway and MRP1 expression.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Doxorrubicina/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resveratrol/farmacologia , Antibióticos Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Células HL-60 , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Transdução de Sinais/efeitos dos fármacos
3.
IEEE Trans Vis Comput Graph ; 30(3): 1837-1852, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38127601

RESUMO

Label quality issues, such as noisy labels and imbalanced class distributions, have negative effects on model performance. Automatic reweighting methods identify problematic samples with label quality issues by recognizing their negative effects on validation samples and assigning lower weights to them. However, these methods fail to achieve satisfactory performance when the validation samples are of low quality. To tackle this, we develop Reweighter, a visual analysis tool for sample reweighting. The reweighting relationships between validation samples and training samples are modeled as a bipartite graph. Based on this graph, a validation sample improvement method is developed to improve the quality of validation samples. Since the automatic improvement may not always be perfect, a co-cluster-based bipartite graph visualization is developed to illustrate the reweighting relationships and support the interactive adjustments to validation samples and reweighting results. The adjustments are converted into the constraints of the validation sample improvement method to further improve validation samples. We demonstrate the effectiveness of Reweighter in improving reweighting results through quantitative evaluation and two case studies.

4.
IEEE Trans Vis Comput Graph ; 30(1): 76-86, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37883267

RESUMO

Existing model evaluation tools mainly focus on evaluating classification models, leaving a gap in evaluating more complex models, such as object detection. In this paper, we develop an open-source visual analysis tool, Uni-Evaluator, to support a unified model evaluation for classification, object detection, and instance segmentation in computer vision. The key idea behind our method is to formulate both discrete and continuous predictions in different tasks as unified probability distributions. Based on these distributions, we develop 1) a matrix-based visualization to provide an overview of model performance; 2) a table visualization to identify the problematic data subsets where the model performs poorly; 3) a grid visualization to display the samples of interest. These visualizations work together to facilitate the model evaluation from a global overview to individual samples. Two case studies demonstrate the effectiveness of Uni-Evaluator in evaluating model performance and making informed improvements.

5.
Front Plant Sci ; 14: 1222755, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731975

RESUMO

The duration of soybean growth and development is regulated by E1-E4 allele genes, which form the basis for ecological adaptation related to biomass accumulation, flowering and pod formation, maturation, and yield. To elucidate the effects of different combinations of E1-E4 allele genes on soybean ecological adaptation, this study conducted competitive allele-specific PCR (KASP) analysis and photoperiod gene typing on 101 main soybean cultivars from different latitudes in China. The ecological adaptation of these cultivars in Sichuan was also investigated. The results showed that within a certain range (60-95 days), soybean varieties with a genotype combination of E1/e2-ns/E3/E4 exhibited a longer growth period and demonstrated higher biomass and yield, displaying overall better performance. These varieties showed strong ecological adaptation in the Chengdu Plain region and are suitable for introduction in similar low to mid-latitude areas like the Chengdu Plain (30°N~32°N). Conversely, soybean varieties carrying a higher number of recessive alleles of E1-E4 are not suitable for introduction in this region.

6.
Plants (Basel) ; 11(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36145811

RESUMO

SMXL6,7,8 are important target proteins in strigolactone (SL) signal pathway, which negatively regulate the reception and response of SL signal, and play an important role in regulating plant branching. However, there is a relative lack of research on soybean SMXL gene family. In this study, 31 soybean SMXL genes were identified by phylogenetic analysis and divided into three groups. Based on the analysis of GmSMXL gene's structure and motif composition, it was found that the GmSMXL members in the same group were similar. The results of cis-element analysis showed that GmSMXL genes may regulate the growth and development of soybean by responding to hormones and environment. Based on the tissue specificity analysis and GR24 treatment, the results showed that four GmSMXLs in G1 group were predominantly expressed in stems, axillary buds and leaves and involved in SL signal pathway. Finally, under shading stress, the expression of four genes in G1 group was slightly different in different varieties, which may be the reason for the difference in branching ability of different varieties under shading stress. We have systematically studied the SMXL gene family in soybean, which may lay a foundation for the study of the function of GmSMXL gene in the future.

7.
Exp Hematol ; 77: 6-11, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31442465

RESUMO

Auer rod-like inclusions are rarely seen in B-cell neoplasms patients. Here, we present a case of B-cell lymphoma with Auer rod-like inclusions in lymphoma cells. By light and transmission electron microscopy, these structures closely resembled Auer rods which were found in acute myeloid leukemia. The Auer rod-like inclusions were negative for cytochemical staining of MPO, α-naphthyl acetate esterase, and periodic acid-Schiff. Immunostaining and flow cytometric analysis confirmed monoclonal Kappa-positive malignant lymphocytes. Interestingly, the Auer rod-like inclusions exhibited diverse ultrastructural features, which ranged from fusiform, to needle-shape, to round, to crystalline cuboid, to long rod, to short rod and others; some were membrane structures, some membrane-free dense structures, and some lamellar structures. The patient was diagnosed with B-cell lymphoma with bone marrow infiltration.


Assuntos
Neoplasias da Medula Óssea , Medula Óssea , Corpos de Inclusão , Linfoma de Células B , Idoso , Medula Óssea/metabolismo , Medula Óssea/patologia , Neoplasias da Medula Óssea/diagnóstico , Neoplasias da Medula Óssea/metabolismo , Neoplasias da Medula Óssea/patologia , Neoplasias da Medula Óssea/secundário , Humanos , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Linfoma de Células B/diagnóstico , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Masculino
8.
Nanoscale ; 10(6): 2774-2780, 2018 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-29323375

RESUMO

A lithium-sulfur (Li-S) battery is regarded as the most promising candidate for next generation energy storage systems, because of its high theoretical specific capacity (1675 mA h g-1) and specific energy (2500 W h kg-1), as well as the abundance, low cost and environmental benignity of sulfur. However, the soluble polysulfides Li2Sx (4 ≤ x ≤ 8) produced during the discharge process can cause the so-called "shuttle effect" and lead to low coulombic efficiency and rapid capacity fading of the batteries, which seriously restrict their practical application. Using porous materials as hosts to immobilize the polysulfides is proved to be an effective strategy. In this article, a dual functional cage-like metal-organic framework (Cu-MOF), Cu-TDPAT, combining the Lewis basic sites from the nitrogen atoms of the ligand H6TDPAT with the Lewis acidic sites from Cu(ii) open metal sites (OMSs), was employed as the sulfur host in a Li-S battery for lithium ions and polysulfide anions (Sx2-). In addition, the size of nano-Cu-TDPAT was also optimized by microwave synthesis to reduce the internal resistance of the batteries. The electrochemical test results showed that the optimized Cu-TDPAT material can efficiently confine the polysulfides within the MOF, and the resultant porous S@Cu-TDPAT composite cathode material with the size of 100 nm shows good cycling performance with a reversible capacity of about 745 mA h g-1 at 1C (1C = 1675 mA g-1) after 500 cycles, to the best of our knowledge, which is higher than those of all reported S@MOF cathode materials. The DFT calculation and XPS data indicate that the good cycling performance mainly results from the dual functional binding sites (that is, Lewis acid and base sites) in nanoporous Cu-TDPAT, providing the comprehensive and robust interaction with the polysulfides to overcome their dissolution and diffusion into the electrolyte. Clearly, our work provides a good example of designing MOFs with suitable interaction sites for the polysulfides to achieve S@MOF cathode materials with excellent cycling performance by multiple synergistic effects between nanoporous host MOFs and the polysulfides.

9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(3): 736-742, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28641627

RESUMO

OBJECTIVE: To explore the mechanism of apoptosis for resvertrol-mediated reversing the drug-resistance of AML HL-60/ADR cells. METHODS: The HL-60/ADR cells were divided into 4 groups: control group, adriamycin (ADR)-treated group, resveratrol(Res)-treated group and ADR+Res-treated group. The inhibitory rate of cell proliferation was analyzed by CCK-8 method. The auto-fluorescence intensity of intracellular ADR and the apoptotic rate of HL-60/ADR cells were detected by flow cytometry. The mRNA expression levels of multidrug-resistance associated protein-1(MRP1), anti-apoptotic gene BCL-2 and pro-apoptotic gene BAX were analyzed by real-time fluorescence quantitative RT-PCR. The protein expression levels of MRP1, BCL-2 and BAX were detected by Western blot. RESULTS: The maximal inhibition rates of cell proliferation were 44%, 61%, 76% and 81%, respectively in different concentration of Res (25, 50, 100, 200 µmol/L) and with concentration-dependent manner(r=0.876, P<0.05). Compared with ADR group (IC50: 8.534±1.111 µmol/L), the half inhibitory concentration (IC50) of HL-60/ADR cells [(1.591±0.373) µmol/L] decreased significantly in ADR+Res group(P<0.05). The auto-fluorescence intensity of ADR in HL-60/ADR cells of ADR+Res group increased significantly (P<0.05). The apoptotic rate of HL-60/ADR cells in Res or ADR+Res group increased significantly (P<0.05). The mRNA expression levels of MRP1 and Bcl-2 in Res or ADR+Res groups decreased and BAX increased significantly (P<0.05). The protein expression levels of MRP1 and BCL-2 were decreased, BAX increased significantly in Res or ADR+Res group (P<0.05). CONCLUSION: Resveratrol shows the effect of reversing the drug resisitance of HL-60/ADR cells in acute myeloid leukemia, possibly via promoting the apoptosis of HL-60/ADR cells and inhibiting the expression of MRP1, which may be related with the inhibition of BCL-2 expression and the promotion of BAX expression.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Promielocítica Aguda/tratamento farmacológico , Estilbenos/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Células HL-60 , Humanos , Resveratrol
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