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1.
Opt Express ; 32(7): 12243-12256, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571053

RESUMEN

Integral imaging is a kind of true three-dimensional (3D) display technology that uses a lens array to reconstruct vivid 3D images with full parallax and true color. In order to present a high-quality 3D image, it's vital to correct the axial position error caused by the misalignment and deformation of the lens array which makes the reconstructed lights deviate from the correct directions, resulting in severe voxel drifting and image blurring. We proposed a sub-pixel marking method to measure the axial position error of the lenses with great accuracy by addressing the sub-pixels under each lens and forming a homologous sub-pixel pair. The proposed measurement method relies on the geometric center alignment of image points, which is specifically expressed as the overlap between the test 3D voxel and the reference 3D voxel. Hence, measurement accuracy could be higher. Additionally, a depth-based sub-pixel correction method was proposed to eliminate the voxel drifting. The proposed correction method takes the voxel depth into consideration in the correction coefficient, and achieves accurate error correction for 3D images with different depths. The experimental results well confirmed that the proposed measuring and correction methods can greatly suppress the voxel drifting caused by the axial position error of the lenses, and greatly improve the 3D image quality.

2.
Drug Resist Updat ; 66: 100907, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36527888

RESUMEN

The binding of programmed death-1 (PD-1) on the surface of T cells and PD-1 ligand 1 (PD-L1) on tumor cells can prevent the immune-killing effect of T cells on tumor cells and promote the immune escape of tumor cells. Therefore, immune checkpoint blockade targeting PD-1/PD-L1 is a reliable tumor therapy with remarkable efficacy. However, the main challenges of this therapy are low response rate and acquired resistance, so that the outcomes of this therapy are usually unsatisfactory. This review begins with the description of biological structure of the PD-1/PD-L1 immune checkpoint and its role in a variety of cells. Subsequently, the therapeutic effects of immune checkpoint blockers (PD-1 / PD-L1 inhibitors) in various tumors were introduced and analyzed, and the reasons affecting the function of PD-1/PD-L1 were systematically analyzed. Then, we focused on analyzing, sorting out and introducing the possible underlying mechanisms of primary and acquired resistance to PD-1/PD-L1 blockade including abnormal expression of PD-1/PD-L1 and some factors, immune-related pathways, tumor immune microenvironment, and T cell dysfunction and others. Finally, promising therapeutic strategies to sensitize the resistant patients with PD-1/PD-L1 blockade treatment were described. This review is aimed at providing guidance for the treatment of various tumors, and highlighting the drug resistance mechanisms to offer directions for future tumor treatment and improvement of patient prognosis.


Asunto(s)
Resistencia a Antineoplásicos , Neoplasias , Receptor de Muerte Celular Programada 1 , Humanos , Antígeno B7-H1 , Resistencia a Medicamentos , Inmunoterapia , Microambiente Tumoral
3.
Zhongguo Zhong Yao Za Zhi ; 48(22): 6154-6163, 2023 Nov.
Artículo en Zh | MEDLINE | ID: mdl-38114222

RESUMEN

This study aims to investigate the mechanism of muscone in inhibiting the opening of mitochondrial permeability transition pore(mPTP) to alleviate the oxygen and glucose deprivation/reoxygenation(OGD/R)-induced injury of mouse hippocampal neurons(HT22). An in vitro model of HT22 cells injured by OGD/R was established. CCK-8 assay was employed to examine the viability of HT22 cells, fluorescence microscopy to measure the mitochondrial membrane potential, the content of reactive oxygen species(ROS), and the opening of mPTP in HT22 cells. Enzyme-linked immunosorbent assay was employed to determine the level of ATP and the content of cytochrome C(Cyt C) in mitochondria of HT22 cells. Flow cytometry was employed to determine the Ca~(2+) content and apoptosis of HT22 cells. The expression of Bcl-2(B-cell lymphoma-2) and Bcl-2-associated X protein(Bax) was measured by Western blot. Molecular docking and Western blot were employed to examine the binding between muscone and methyl ethyl ketone(MEK) after pronase hydrolysis of HT22 cell proteins. After the HT22 cells were treated with U0126, an inhibitor of MEK, the expression levels of MEK, p-ERK, and CypD were measured by Western blot. The results showed that compared with the OGD/R model group, muscone significantly increased the viability, mitochondrial ATP activity, and mitochondrial membrane potential, lowered the levels of ROS, Cyt C, and Ca~(2+), and reduced mPTP opening to inhibit the apoptosis of HT22 cells. In addition, muscone up-regulated the expression of MEK, p-ERK, and down-regulated that of CypD. Molecular docking showed strong binding activity between muscone and MEK. In conclusion, muscone inhibits the opening of mPTP to inhibit apoptosis, thus exerting a protective effect on OGD/R-injured HT22 cells, which is associated with the activation of MEK/ERK/CypD signaling pathway.


Asunto(s)
Apoptosis , Oxígeno , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , Simulación del Acoplamiento Molecular , Adenosina Trifosfato/farmacología , Quinasas de Proteína Quinasa Activadas por Mitógenos/farmacología , Glucosa/metabolismo
4.
Insect Sci ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844429

RESUMEN

Psocodean species are emerging as significant sanitary and stored-product pests, posing threats to human health and global food security. Out of an estimated 10 000 species, the whole genome sequences of only 4 species have been published. Genomic resources are crucial for establishing effective pest control and enhancing our understanding of the evolution of psocodean species. In this study, we employed Illumina and PacBio sequencing along with Hi-C scaffolding techniques to generate a chromosome-level genome assembly for the parthenogenetic booklouse Liposcelis bostrychophila. The assembled genome of this booklouse measures 291.67 Mb in length and comprises 9 chromosomes. Notably, the genome of L. bostrychophila exhibits a high level of heterozygosity and features a distinctive nonhomologous chromosome. This heterozygous characteristic of the parthenogenetic booklouse genome may arise from high mutation rates, based on genomic variations analysis across multiple generations. Our analysis revealed significantly expanded gene families, primarily associated with the detoxification and feeding habits of L. bostrychophila. These include integument esterases (ESTs), ATP-binding cassette (ABC) transporter genes and gustatory receptors (GRs). The high-quality genome sequence of L. bostrychophila provides valuable resources for further study on the molecular mechanisms of stress resistance. It enables researchers to identify crucial functional genes and facilitates research on the population genetics, evolution and phylogeny of booklice.

5.
Transl Androl Urol ; 13(5): 812-827, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38855608

RESUMEN

Background: Solasonine has been demonstrated to exert an inhibitory effect on bladder cancer (BC), but the potential mechanisms remain unclear. Therefore, the aim of this study is to explore the association between microRNAs (miRNAs)-mediated regulation and the anti-tumor activities of solasonine in BC. Methods: MiRNA sequencing was performed to identify the differentially expressed microRNAs (DE-miRNAs) associated with solasonine in BC cells. Functional enrichment analyses of the DE-miRNAs activated and inhibited by solasonine were then conducted. The DE-miRNAs with prognostic value for BC and those differentially expressed in the BC samples were subsequently identified as the hub DE-miRNAs. After identifying the messenger RNAs (mRNAs) that were targeted by the hub DE-miRNAs and those differentially expressed in the BC samples, a protein-protein interaction analysis was performed to identify the core downstream genes, which were then used to construct a solasonine-miRNA-mRNA regulatory network. Results: A total of 27 activated and 19 inhibited solasonine-mediated DE-miRNAs were identified that were found to be associated with several tumor-related biological functions and pathways. After integrating the results of the survival analysis and expression assessment, the following nine hub DE-miRNAs were identified: hsa-miR-127-3p, hsa-miR-450b-5p, hsa-miR-99a-5p, hsa-miR-197-3p, hsa-miR-423-3p, hsa-miR-4326, hsa-miR-625-3p, hsa-miR-625-5p, and hsa-miR-92a-3p. The DE-mRNAs targeted by the hub DE-miRNAs were predicted, and 30 core downstream genes were used to construct the solasonine-miRNA-mRNA regulatory network. miR-450b-5p was shown to be associated with the most mRNAs in this network, which suggests that it plays a crucial role in the solasonine-mediated anti-BC effect. Conclusions: A regulatory network, including solasonine, miRNAs, and mRNAs related to BC, was constructed. This network provides extensive insights into the molecular regulatory mechanisms that underlie the anti-cancer efficacy of solasonine in BC.

6.
Transl Cancer Res ; 12(8): 1992-2007, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37701108

RESUMEN

Background: High-grade bladder cancer (HGBC) has a higher malignant potential, recurrence and progression rate compared to low-grade phenotype. Its early symptoms are often vague, making non-invasive diagnosis using urinary biomarkers a promising approach. Methods: The gene expression data from urine samples of patients with HGBC was extracted from the GSE68020 dataset. The clinical information and gene expression data in tumor tissues of HGBC patients were obtained from The Cancer Genome Atlas (TCGA) database. Multivariate Cox analysis was used to predict the optimal risk model. The protein-protein interaction (PPI) analysis was performed via the Search Tool for the Retrieval of Interacting Genes (STRING) database and visualized using Cytoscape. Overall survival (OS) was evaluated in the Gene Expression Profiling Interactive Analysis (GEPIA) online platform. Competing endogenous RNA (ceRNA) network was also visualized using Cytoscape. The expression levels of specific genes were assessed through quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Moreover, co-expressed genes and potential biological functions related to specific genes were explored based on the Cancer Cell Line Encyclopedia (CCLE) database. Results: A total of 560 differentially expressed genes (DEGs) were identified when comparing the urine sediment samples from HGBC patients with the benign ones. Using these urinary DEGs and the clinical information of HGBC patients, we developed an optimal risk model consisting of eight genes to predict the patient outcome. By integrating the node degree values in the PPI network with the expression changes in both urine and tissue samples, eighteen hub genes were selected out. Among them, DKC1 and SNRPG had the most prominent comprehensive values, and EFTUD2, LOR and EBNA1BP2 were relevant to a worse OS in bladder cancer patients. The ceRNA network of hub genes indicated that DKC1 may be directly regulated by miR-150 in HGBC. The upregulation of both SNRPG and DKC1 were detected in HGBC cells, which were also observed in various tumor tissues and malignant cell lines, displaying high correlations with other hub genes. Conclusions: Our study may provide theoretical basis for the development of effective non-invasive detection and treatment strategies, and further research is necessary to explore the clinical applications of these findings.

7.
Adv Sci (Weinh) ; 10(23): e2300256, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37232232

RESUMEN

Lead halide perovskites have made remarkable progress in the field of radiation detection owing to the excellent and unique optoelectronic properties. However, the instability and the toxicity of lead-based perovskites have greatly hindered its practical applications. Alternatively, lead-free perovskites with high stability and environmental friendliness thus have fascinated significant research attention for direct X-ray detection. In this review, the current research progress of X-ray detectors based on lead-free halide perovskites is focused. First, the synthesis methods of lead-free perovskites including single crystals and films are discussed. In addition, the properties of these materials and the detectors, which can provide a better understanding and designing satisfactory devices are also presented. Finally, the challenge and outlook for developing high-performance lead-free perovskite X-ray detectors are also provided.

8.
Adv Mater ; 35(47): e2304128, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37540571

RESUMEN

A high configurational entropy, achieved through a proper design of compositions, can minimize the Gibbs free energy and stabilize the quasi-equilibrium phases in a solid-solution form. This leads to the development of high-entropy materials with unique structural characteristics and excellent performance, which otherwise could not be achieved through conventional pathways. This work develops a high-entropy nonlinear dielectric system, based on the expansion of lead magnesium niobate-lead titanate. A dense and uniform distribution of nano-polar regions is observed in the samples owing to the addition of Ba, Hf, and Zr ions, which lead to enhanced performance of nonlinear dielectrics. The fact that no structural phase transformation is detected up to 250 °C, and no noticeable change or a steep drop in structural and electrical characteristics is observed at high temperatures suggests a robust thermal stability of the dielectric systems developed. With these advantages, these materials hold vast potential for applications such as dielectric energy storage, dielectric tunability, and electrocaloric effect. Thus, this work offers a new high-entropy configuration with elemental modulation, with enhanced dielectric material features.

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