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Netrins, a family of secreted and membrane-associated proteins, can regulate axonal guidance, morphogenesis, angiogenesis, cell migration, cell survival, and tumorigenesis. Four secreted netrins (netrin 1, 3, 4 and 5) and two glycosylphosphatidylinositols-anchored membrane proteins, netrin-G1 and G2, have been identified in mammals. Netrins and their receptors can serve as a biomarker and molecular therapeutic target for pathological differentiation, diagnosis and prognosis of malignant cancers. We review here the potential roles of the netrins family and their receptors in cancer.
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Neoplasias , Animais , Netrinas , Transporte Biológico , Carcinogênese , Diferenciação Celular , Proteínas de Membrana , MamíferosRESUMO
Fruit length is a crucial agronomic trait of snake gourd (Trichosanthes anguina L); however, genes associated with fruit length have not been characterised. In this study, F2 snake gourd populations were generated by crossing the inbred lines, S1 and S2 (fruit lengths: 110 and 20 cm, respectively). Subsequently, bulk segregant analysis, sequencing, and fine-mapping were performed on the F2 population to identify target genes. Our findings suggest that the fruit length of snake gourd is regulated by a major-effect regulatory gene. Mining of genes regulating fruit length in snake gourd to provide a basis for subsequent selection and breeding of new varieties. Genotype-phenotype association analysis was performed on the segregating F2 population comprising 6,000 plants; the results indicate that the target gene is located on Chr4 (61,846,126-61,865,087 bp, 18.9-kb interval), which only carries the annotated candidate gene, Tan0010544 (designated TFL). TFL belongs to the MADS-box family, one of the largest transcription factor families. Sequence analysis revealed a non-synonymous mutation of base C to G at position 202 in the coding sequence of TFL, resulting in the substitution of amino acid Gln to Glu at position 68 in the protein sequence. Subsequently, an InDel marker was developed to aid the marker-assisted selection of TFL. The TFL in the expression parents within the same period was analysed using quantitative real-time PCR; the TFL expression was significantly higher in short fruits than long fruits. Therefore, TFL can be a candidate gene for determining the fruit length in snake gourd. Collectively, these findings improve our understanding of the genetic components associated with fruit length in snake gourds, which could aid the development of enhanced breeding strategies for plant species.
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Trichosanthes , Trichosanthes/genética , Frutas/genética , Melhoramento Vegetal , Fenótipo , Genes de Plantas/genéticaRESUMO
Adzuki bean (Vigna angularis) is an important legume crop cultivated in over 30 countries worldwide. We developed a high-quality chromosome-level reference genome of adzuki bean cultivar Jingnong6 by combining PacBio Sequel long-read sequencing with short-read and Hi-C technologies. The assembled genome covers 97.8% of the adzuki bean genome with a contig N50 of approximately 16 Mb and a total of 32 738 protein-coding genes. We also generated a comprehensive genome variation map of adzuki bean by whole-genome resequencing (WGRS) of 322 diverse adzuki beans accessions including both wild and cultivated. Furthermore, we have conducted comparative genomics and a genome-wide association study (GWAS) on key agricultural traits to investigate the evolution and domestication. GWAS identified several candidate genes, including VaCycA3;1, VaHB15, VaANR1 and VaBm, that exhibited significant associations with domestication traits. Furthermore, we conducted functional analyses on the roles of VaANR1 and VaBm in regulating seed coat colour. We provided evidence for the highest genetic diversity of wild adzuki (Vigna angularis var. nipponensis) in China with the presence of the most original wild adzuki bean, and the occurrence of domestication process facilitating transition from wild to cultigen. The present study elucidates the genetic basis of adzuki bean domestication traits and provides crucial genomic resources to support future breeding efforts in adzuki bean.
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Genoma de Planta , Estudo de Associação Genômica Ampla , Vigna , Genoma de Planta/genética , Vigna/genética , Cromossomos de Plantas/genética , Domesticação , Variação Genética , Genômica , Produtos Agrícolas/genética , FenótipoRESUMO
In order to meet the ground calibration requirements of optical detection equipment to identify optical characteristics of dim targets, an optical simulation method of dim targets based on passive detection link analysis and bidirectional scattering distribution function model is proposed. The off-axis collimation system for long focal length, the simulated energy transmission model of dim targets and the simplified model of bidirectional scattering distribution function are established. An internal stray light suppression baffle was designed to effectively suppress secondary scattering, and an optical simulation system for dim targets was built. The experimental results show that the system can simulate +7 Mvâ¼+20 Mv, and the simulation accuracy is better than 0.07 Mv. At the same time, the detection ability of the camera is tested by using the +15 Mv point simulated by the system. The signal-to-noise of the star point target reaches 6.7, which meets the requirements of detection rate and false alarm rate, and realizes the ground test of the camera's detection ability of the dim target.
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Accurate protein-ligand binding poses are the prerequisites of structure-based binding affinity prediction and provide the structural basis for in-depth lead optimization in small molecule drug design. However, it is challenging to provide reasonable predictions of binding poses for different molecules due to the complexity and diversity of the chemical space of small molecules. Similarity-based molecular alignment techniques can effectively narrow the search range, as structurally similar molecules are likely to have similar binding modes, with higher similarity usually correlated to higher success rates. However, molecular similarity is not consistently high because molecules often require changes to achieve specific purposes, leading to reduced alignment precision. To address this issue, we propose a new alignment methodâZ-align. This method uses topological structural information as a criterion for evaluating similarity, reducing the reliance on molecular fingerprint similarity. Our method has achieved success rates significantly higher than those of other methods at moderate levels of similarity. Additionally, our approach can comprehensively and flexibly optimize bond lengths and angles of molecules, maintaining a high accuracy even when dealing with larger molecules. Consequently, our proposed solution helps in achieving more accurate binding poses in protein-ligand docking problems, facilitating the development of small molecule drugs. Z-align is freely available as a web server at https://cloud.zelixir.com/zalign/home.
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Simulação de Acoplamento Molecular , Proteínas , Ligantes , Proteínas/química , Proteínas/metabolismo , Ligação Proteica , Desenho de Fármacos , Conformação Proteica , Sítios de LigaçãoRESUMO
BACKGROUND AND AIM: Lipid metabolism disorder is the primary feature of numerous refractory chronic diseases. Fatty acid oxidation, an essential aerobic biological process, is closely related to the progression of NAFLD. The forkhead transcription factor FOXO1 has been reported to play an important role in lipid metabolism. However, the molecular mechanism through which FOXO1 regulates fatty acid oxidation remains unclear. METHODS: Transcriptomic analysis was performed to examine the cellular expression profile to determine the functional role of FOXO1 in HepG2 cells with palmitic acid (PA)-induced lipid accumulation. FOXO1-binding motifs at the promoter region of aldehyde dehydrogenase 1 family member L2 (ALDH1L2) were predicted via bioinformatic analysis and confirmed via luciferase reporter assay. Overexpression of ALDH1L2 was induced to recover the impaired fatty acid oxidation in FOXO1-knockout cells. RESULTS: Knockout of FOXO1 aggravated lipid deposition in hepatic cells. Transcriptomic profiling revealed that knockout of FOXO1 increased the expression of genes associated with fatty acid synthesis but decreased the expression of carnitine palmitoyltransferase1a (CPT1α) and adipose triglyceride lipase (ATGL), which contribute to fatty acid oxidation. Mechanistically, FOXO1 was identified as a transcription factor of ALDH1L2. Knockout of FOXO1 significantly decreased the protein expression of ALDH1L2 and CPT1α in vitro and in vivo. Furthermore, overexpression of ALDH1L2 restored fatty acid oxidation in FOXO1-knockout cells. CONCLUSION: The findings of this study indicate that FOXO1 modulates fatty acid oxidation by targeting ALDH1L2.
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PURPOSE: This pilot study aimed to investigate the effects of REX exoskeleton rehabilitation robot training on the balance and lower limb function in patients with sub-acute stroke. METHODS: This was a pilot, single-blind, randomized controlled trial. Twenty-four patients with sub-acute stroke (with the course of disease ranging from 3 weeks to 3 months) were randomized into two groups, including a robot group and a control group. Patients in control group received upright bed rehabilitation (n = 12) and those in robot group received exoskeleton rehabilitation robot training (n = 12). The frequency of training in both groups was once a day (60 min each) for 5 days a week for a total of 4 weeks. Besides, the two groups were evaluated before, 2 weeks after and 4 weeks after the intervention, respectively. The primary assessment index was the Berg Balance Scale (BBS), whereas the secondary assessment indexes included the Fugl-Meyer Lower Extremity Motor Function Scale (FMA-LE), the Posture Assessment Scale for Stroke Patients (PASS), the Activities of Daily Living Scale (Modified Barthel Index, MBI), the Tecnobody Balance Tester, and lower extremity muscle surface electromyography (sEMG). RESULTS: The robot group showed significant improvements (P < 0.05) in the primary efficacy index BBS, as well as the secondary efficacy indexes PASS, FMA-LE, MBI, Tecnobody Balance Tester, and sEMG of the lower limb muscles. Besides, there were a significant differences in BBS, PASS, static eye-opening area or dynamic stability limit evaluation indexes between the robotic and control groups (P < 0.05). CONCLUSIONS: This is the first study to investigate the effectiveness of the REX exoskeleton rehabilitation robot in the rehabilitation of patients with stroke. According to our results, the REX exoskeleton rehabilitation robot demonstrated superior potential efficacy in promoting the early recovery of balance and motor functions in patients with sub-acute stroke. Future large-scale randomized controlled studies and follow-up assessments are needed to validate the current findings. CLINICAL TRIALS REGISTRATION: URL: https://www.chictr.org.cn/index.html.Unique identifier: ChiCTR2300068398.
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Exoesqueleto Energizado , Extremidade Inferior , Equilíbrio Postural , Robótica , Reabilitação do Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/instrumentação , Reabilitação do Acidente Vascular Cerebral/métodos , Masculino , Projetos Piloto , Feminino , Pessoa de Meia-Idade , Extremidade Inferior/fisiopatologia , Equilíbrio Postural/fisiologia , Método Simples-Cego , Robótica/instrumentação , Idoso , Adulto , Acidente Vascular Cerebral/fisiopatologia , Eletromiografia , Resultado do Tratamento , Recuperação de Função FisiológicaRESUMO
Due to the limitations of traditional ultraviolet (UV) in microbial inactivation in water, it is necessary to explore a more suitable and efficient UV disinfection method. In this study, an electron beam excitation multi-wavelength ultraviolet (EBE-MW-UV) system was established and aims to analyze its differential microbial inactivation capabilities in comparison to single-wavelength UV-LEDs in waterborne applications. Furthermore, the inactivation mechanisms of this system on microorganisms were explored. The results showed that EBE-MW-UV had significantly higher inactivation effects on the Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans in water compared to UV-LEDs (pï¼0.05), and the inactivation effect of EBE-MW-UV on Escherichia coli and Pseudomonas aeruginosa at the same UV dose was 3.8 and 1.9 log higher than that of UV-LEDs, respectively, EBE-MW-UV exhibited better inactivation effects on Gram-negative bacteria. Further research found that, under the majority of irradiation doses, neither EBE-MW-UV nor UV-LEDs were significantly affected by the concentration of suspended solids (5 and 20 mg/L) or humic acids (2 and 5 mg/L) in the water. Mechanism analysis revealed that during the disinfection process of EBE-MW-UV, microbial DNA and proteins were initially damaged, which prevented the occurrence of dark repair and led to bacterial inactivation. In addition, UV irradiation led to the production of additional reactive oxygen species (ROS) inside the cells, increasing cell membrane permeability and exacerbating membrane damage. This was accompanied by a decrease in energy metabolism and depletion of ATP, ultimately resulting in microbial inactivation. Therefore, EBE-MW-UV demonstrated more effective disinfection than single-wavelength UV-LEDs, showing great potential. Our research gives new insights into the characteristics of multiple wavelength ultraviolet, and provides scientific basis for the selection of new light sources in the field of ultraviolet disinfection.
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Purificação da Água , Água , Elétrons , Purificação da Água/métodos , Microbiologia da Água , Raios Ultravioleta , Escherichia coli , Desinfecção/métodosRESUMO
Left-behind children, as a large-scale disadvantaged group, encounter an array of risk factors that impede their academic development because of parental migration. The current study aimed at investigating the roles of left-behind cumulative risk and growth mindset on academic adjustment and exploring whether growth mindset moderated the association between left-behind cumulative risk and academic adjustment in left-behind middle school students. A total of 1184 left-behind middle school students (615 males; 12-16 years) participated in the study. Results indicated that left-behind cumulative risk is negatively associated with academic adjustment in middle school students (ß = -.199, t(1183) = -7.229, p < .001). Besides, growth mindset has a protective effect on left-behind middle school students' academic adjustment (ß = .386, t(1183) = 14.070, p < .001) and a moderating effect on the relationship between left-behind cumulative risk and academic adjustment (ß = .394, t(1182) = 4.057, p < .001, ΔR2 = .012). These findings suggest that family risk factors related to left-behind status affect the academic adjustment of left-behind middle school students in a superposition way, while the positive individual factor of growth mindset could protect the negative impact caused by parental migration.
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BACKGROUND: In plants, RNA silencing is an important conserved mechanism to regulate gene expression and combat against abiotic and biotic stresses. Dicer-like (DCL) and Argonaute (AGO) proteins and RNA-dependent RNA polymerase (RDR) are the core elements involved in gene silencing and their gene families have been explored in many plants. However, these genes and their responses to stresses have not yet been well characterized in adzuki bean. RESULTS: A total of 11 AGO, 7 DCL and 6 RDR proteins were identified, and phylogenetic analyses of these proteins showed that they clustered into six, four and four clades respectively. The expression patterns of these genes in susceptible or resistant adzuki bean cultivars challenged with drought, bean common mosaic virus and Podosphaera xanthii infections were further validated by quantitative RT-PCR. The different responses of these proteins under abiotic and biotic stresses indicated their specialized regulatory mechanisms. CONCLUSIONS: In this study, 24 genes of the DCL, AGO and RDR gene families in adzuki bean were identified, and the sequence characterization, structure of the encoded proteins, evolutionary relationship with orthologues in other legumes and gene expression patterns under drought and biotic stresses were primarily explored, which enriched our understanding of these genes in adzuki bean. Our findings provide a foundation for the comparative genomic analyses of RNA silencing elements in legume plants and further new insights into the functional complexity of RNA silencing in the response to various stresses in adzuki bean.
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Fabaceae , Vigna , Vigna/genética , Filogenia , Interferência de RNA , Secas , Genoma de Planta , Fabaceae/genética , Fabaceae/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Elevated impulsivity has been frequently reported in individuals with opioid addiction receiving methadone maintenance therapy (MMT), but the underlying neural mechanisms and cognitive subprocesses are not fully understood. We acquired functional magnetic resonance imaging (fMRI) data from 37 subjects with heroin addiction receiving long-term MMT and 33 healthy controls who performed a probabilistic reversal learning task, and measured their resting-state brain glucose using fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET). Subjects receiving MMT exhibited significantly elevated self-reported impulsivity, and computational modeling revealed a marked impulsive decision bias manifested as switching more frequently without available evidence. Moreover, this impulsive decision bias was associated with the dose and duration of methadone use, irrelevant to the duration of heroin use. During the task, the switch-related hypoactivation in the left rostral middle frontal gyrus was correlated with the impulsive decision bias while the function of reward sensitivity was intact in subjects receiving MMT. Using prior brain-wide receptor density data, we found that the highest variance of regional metabolic abnormalities was explained by the spatial distribution of µ-opioid receptors among 10 types of neurotransmitter receptors. Heightened impulsivity in individuals receiving prolonged MMT is manifested as atypical choice bias and noise in decision-making processes, which is further driven by deficits in top-down cognitive control, other than reward sensitivity. Our findings uncover multifaceted mechanisms underlying elevated impulsivity in subjects receiving MMT, which might provide insights for developing complementary therapies to improve retention during MMT.
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Dependência de Heroína , Humanos , Dependência de Heroína/tratamento farmacológico , Metadona/uso terapêutico , Heroína/efeitos adversos , Encéfalo/diagnóstico por imagem , Comportamento ImpulsivoRESUMO
Although extensive research has been carried out on the epigenetic regulation of single RNA modifications in gastric cancer, little is known regarding the crosstalk of four major RNA adenosine modifications, namely, m6A, m1A, alternative polyadenylation and adenosine-to-inosine RNA editing. By analyzing 26 RNA modification "writers" in 1750 gastric cancer samples, we creatively constructed a scoring model called the "Writers" of the RNA Modification Score (WRM_Score), which was able to quantify the RNA modification subtypes of individual patients. In addition, we explored the relationship between WRM_Score and transcriptional and posttranscriptional regulation, tumor microenvironment, clinical features and molecular subtypes. We constructed an RNA modification scoring model including two different subgroups: WRM_Score_low and WRM_Score_high. The former was associated with survival benefit and good efficacy of immune checkpoint inhibitors (ICIs) due to gene repair and immune activation, while the latter was related to poor prognosis and bad efficacy of ICIs because of stromal activation and immunosuppression. The WRM score based on immune and molecular characteristics of the RNA modification pattern is a reliable predictor of the prognosis of gastric cancer and the therapeutic efficacy of immune checkpoint inhibitors in gastric cancer.
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Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Epigênese Genética , Inibidores de Checkpoint Imunológico , Imunoterapia , Adenosina/genética , RNA/genética , Microambiente Tumoral/genéticaRESUMO
BACKGROUND: CD133 is considered a marker for cancer stem cells (CSCs) in several types of tumours, including hepatocellular carcinoma (HCC). Chimeric antigen receptor-specific T (CAR-T) cells targeting CD133-positive CSCs have emerged as a tool for the clinical treatment of HCC, but immunogenicity, the high cost of clinical-grade recombinant viral vectors and potential insertional mutagenesis limit their clinical application. METHODS: CD133-specific CAR-T cells secreting PD-1 blocking scFv (CD133 CAR-T and PD-1 s cells) were constructed using a sleeping beauty transposon system from minicircle technology, and the antitumour efficacy of CD133 CAR-T and PD-1 s cells was analysed in vitro and in vivo. RESULTS: A univariate analysis showed that CD133 expression in male patients at the late stage (II and III) was significantly associated with worse progression-free survival (PFS) (P = 0.0057) and overall survival (OS) (P = 0.015), and a multivariate analysis showed a trend toward worse OS (P = 0.041). Male patients with advanced HCC exhibited an approximately 20-fold higher PD-L1 combined positive score (CPS) compared with those with HCC at an early stage. We successfully generated CD133 CAR-T and PD-1 s cells that could secrete PD-1 blocking scFv based on a sleeping beauty system involving minicircle vectors. CD133 CAR-T and PD-1 s cells exhibited significant antitumour activity against HCC in vitro and in xenograft mouse models. Thus, CD133 CAR-T and PD-1 s cells may be a therapeutically tractable strategy for targeting CD133-positive CSCs in male patients with advanced HCC. CONCLUSIONS: Our study provides a nonviral strategy for constructing CAR-T cells that could also secrete checkpoint blockade inhibitors based on a Sleeping Beauty system from minicircle vectors and revealed a potential benefit of this strategy for male patients with advanced HCC and high CD133 expression (median immunohistochemistry score > 2.284).
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Receptores de Antígenos Quiméricos , Humanos , Masculino , Animais , Camundongos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Receptor de Morte Celular Programada 1 , Receptores de Antígenos Quiméricos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Modelos Animais de Doenças , Linfócitos TRESUMO
The discovery of carbon-based quantum dots (CQDs) has allowed opportunities for fluorescence bioimaging, tumor diagnosis and treatment, and photo-/electro-catalysis. Nevertheless, in the existing reviews related to the "bottom-up" approaches, attention is mainly paid to the applications of CQDs but not the formation mechanism of CQDs, which mainly derived from the high complexities during the synthesis of CQDs. Among the various synthetic methods, using small molecules as "building blocks", the development of a "bottom-up" approach has promoted the structural design, modulation of the photoluminescence properties, and control of the interfacial properties of CQDs. On the other hand, many works have demonstrated the "building blocks"-dependent properties of CQDs. In this review, from one of the most important variables, the relationships among intrinsic properties of "building blocks" and photoluminescence properties of CQDs are summarized. The topology, chirality, and free radical process are selected as descriptors for the intrinsic properties of "building blocks". This review focuses on the induction and summary of recent research results from the "bottom-up" process. Moreover, several empirical rules pertaining thereto are also proposed.
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Immune checkpoint inhibitor (ICI) therapy is insensitive for Colorectal cancer (CRC) patients with microsatellite stable (MSS). Genomic data of three CRC cohort, n = 35), and the Cancer Genome Atlas (TCGA CRC cohort, n = 377), were analyzed. A cohort treated with ICIs from Memorial Sloan Kettering Cancer Center (MSKCC CRC cohort, n = 110) and two cases from the local hospital were characterized the impact of the HRR mutation on prognosis of CRC. Homologous recombination repair (HRR) gene mutations were more common in CN and HL cohorts (27.85%; 48.57%) than in TCGA CRC cohort (15.92%), especially in the MSS populations, the frequencies of HRR mutation were higher in CN and HL cohort (27.45%, 51.72%) than in TCGA cohort (6.85%). HRR mutations were associated with high tumor mutational burden (TMB-H). Although HRR mutation uncorrelated with an improved overall survival in the MSKCC CRC cohort (p = 0.97), HRR mutated patients had a significantly improved OS compared to the HRR wildtype population particularly in MSS subgroups (p = 0.0407) under ICI treatment. It probably contributed by a higher neoantigen and increased CD4+ T cell infiltration which found in the TCGA MSS HRR mutated CRC cohort. The similar phenomenon on cases was observed that MSS metastatic CRC patient with HRR mutation seemed more sensitive to ICI after multi-line chemotherapy in clinical practice than HRR wildtype. This finding suggests the feasibility of HRR mutation as an immunotherapy response predictor in MSS CRC, which highlights a potential therapeutic approach for these patients.
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Neoplasias Colorretais , Inibidores de Checkpoint Imunológico , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Reparo de DNA por Recombinação , Imunoterapia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , MutaçãoRESUMO
Immune checkpoint blockade (ICB) therapies, such as monoclonal antibodies against the PD-1/PD-L1 immune checkpoint pathway, have been a major breakthrough in the treatment of lung cancer especially lung adenocarcinoma (LUAD), but their effectiveness is limited. High expression of PD-L1 in tumor cells is one of the key reasons evading immune surveillance, yet the mechanisms that regulate PD-L1 expression are not fully understood. By analyzing the chromatin immunoprecipitation sequencing data of MYC-associated X-factor (MAX) based on lung cancer cell lines, we found that the transcriptional regulator MAX is able to bind to the promoter region of the PD-L1 gene. Further, we performed several molecular biology experiments to determine that MAX promotes PD-L1 transcription in LUAD cells, which in turn assists LUAD cells to evade killing by CD8+ T cells, an effect that can be reversed by anti-PD-L1 antibody. In LUAD, the expression of MAX is positively correlated with PD-L1 and the infiltration of CD8+ T cells. Importantly, we further identified that high expression of the MAX/PD-L1 axis is associated with poor overall survival and fist progression of patients with LUAD. Thus, this study sheds light on the mechanism by which MAX inhibits CD8+ T cell-mediated killing of LUAD cells by activating PD-L1 transcription, and MAX may serve as a potential combinatorial target for ICB therapies that block the PD-1/PD-L1 pathway in LUAD.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos , Imunoterapia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismoRESUMO
The increasing miniaturization of electronics requires a better understanding of material properties at the nanoscale. Many studies have shown that there is a ferroelectric size limit in oxides, below which the ferroelectricity will be strongly suppressed due to the depolarization field, and whether such a limit still exists in the absence of the depolarization field remains unclear. Here, by applying uniaxial strain, we obtain pure in-plane polarized ferroelectricity in ultrathin SrTiO_{3} membranes, providing a clean system with high tunability to explore ferroelectric size effects especially the thickness-dependent ferroelectric instability with no depolarization field. Surprisingly, the domain size, ferroelectric transition temperature, and critical strain for room-temperature ferroelectricity all exhibit significant thickness dependence. These results indicate that the stability of ferroelectricity is suppressed (enhanced) by increasing the surface or bulk ratio (strain), which can be explained by considering the thickness-dependent dipole-dipole interactions within the transverse Ising model. Our study provides new insights into ferroelectric size effects and sheds light on the applications of ferroelectric thin films in nanoelectronics.
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BACKGROUND: Jujube is an economically important fruit tree and native to China. Viral disease is a new threat to jujube production, and several new viruses have been identified infecting jujube plants. During our field survey, jujube mosaic disease was widely distributed in Beijing, but the associated causal agents are still unknown. METHODS: Small RNA deep sequencing was conducted to identify the candidate viruses associated with jujube mosaic. Further complete genome sequences of the viruses were cloned, and the genomic characterization of each virus was analyzed. The field distribution of these viruses was further explored with PCR/RT-PCR detection of field samples. RESULTS: Mixed infection of four viruses was identified in a plant sample with the symptom of mosaic and leaf twisting, including the previously reported jujube yellow mottle-associated virus (JYMaV), persimmon ampelovirus (PAmpV), a new badnavirus tentatively named jujube-associated badnavirus (JaBV), and a new secovirus tentatively named jujube-associated secovirus (JaSV). PAmpV-jujube was 14,093 nt in length with seven putative open reading frames (ORFs) and shared highest (79.4%) nucleotide (nt) sequence identity with PAmpV PBs3. Recombination analysis showed that PAmpV-jujube was a recombinant originating from plum bark necrosis stem pitting-associated virus isolates nanjing (KC590347) and bark (EF546442). JaBV was 6449 bp in length with conserved genomic organization typical of badnaviruses. The conserved RT and RNAse H region shared highest 67.6% nt sequence identity with jujube mosaic-associated virus, which was below the 80% nt sequence identity value used as the species demarcation threshold in Badnavirus. The genome of JaSV composed of two RNA molecules of 5878 and 3337 nts in length, excluding the polyA tails. Each genome segment contained one large ORF that shared homology and phylogenetic identity with members of the family Secoviridae. Field survey showed JYMaV and JaBV were widely distributed in jujube trees in Beijing. CONCLUSION: Two new viruses were identified from jujube plants, and mixed infections of JYMaV and JaBV were common in jujube in Beijing.
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Badnavirus , Coinfecção , Ziziphus , Filogenia , Ziziphus/genética , Coinfecção/genética , Frutas , Genoma Viral , Badnavirus/genética , RNARESUMO
BACKGROUND AND AIMS: Mitochondrial dysfunction plays a crucial role in the progression of non-alcoholic steatohepatitis (NASH). Mitochondrial division inhibitor 1 (Mdivi1) is a potential inhibitor of dynamin-related protein (Drp1) and mitochondrial fission. However, the therapeutic effect of Mdivi1 against NASH and its underlying molecular mechanisms remain unclear. METHODS: In this study, we established mouse models of NASH by inducing high-fat/high-cholesterol (HFHC) or methionine- and choline-deficient (MCD) diets and treated the animals with 5 mg/kg/day Mdivi1 or placebo. RESULTS: Treatment with Mdivi1 significantly alleviated diet-induced fatty liver phenotypes, including increased liver weight/body weight ratio, insulin resistance, hepatic lipid accumulation, steatohepatitis, and liver injury. Furthermore, Mdivi1 treatment suppressed HFHC or MCD diet-induced changes in the expression of genes related to lipid metabolism and inflammatory cytokines. Additionally, Mdivi1 reduced macrophage infiltration in the injured liver and promoted polarization of macrophages towards the M1 phenotype. At the molecular level, Mdivi1 attenuated mitochondrial fission by reducing Drp1 activation and expression, thereby decreasing mitochondrial reactive oxygen species accumulation and mitochondrial DNA damage. Moreover, Mdivi1-treated mice exhibited elevated levels of phosphorylated-c-Jun N-terminal kinase (p-JNK), mitochondrial fission factor (MFF), cleaved caspase 3 protein, and TUNEL-positive cell expression in the liver, suggesting that Mdivi1 might ameliorate mitochondrial dysfunction and reduce hepatocyte apoptosis by inhibiting the JNK/MFF pathway. CONCLUSION: Collectively, Mdivi1 protected against diet-induced NASH by restoring mitochondrial homeostasis and function, potentially through its inhibitory effect on the JNK/MFF pathway. Consequently, further investigation of Mdivi1 as a promising drug for NASH treatment is warranted.
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Doenças Mitocondriais , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo , Citocinas/metabolismo , Mitocôndrias/metabolismo , Fatores de Transcrição/metabolismo , Colina/metabolismo , Dinaminas , Doenças Mitocondriais/metabolismo , Camundongos Endogâmicos C57BL , Metionina , Modelos Animais de DoençasRESUMO
Fluidic transport down to the nanometer scale is of great importance for a wide range of applications such as energy harvesting, seawater desalination, and water treatment and may help to understand many biological processes. In this work, we studied the interfacial friction of liquid water on a series of nanostructures through molecular dynamics (MD) simulations. Our results reveal that the friction coefficient of the water-solid interface cannot be described using a previously reported simple function of the free energy corrugation. Considering that the water-solid friction is firmly correlated with the microscopic water motion, we proposed a probability parameter P(d, t) to classify water motion modes on a surface. We demonstrate that this parameter can be used to accurately predict the water-solid friction by simply monitoring the water binding time on a nanosurface. More importantly, according to the relationship between P(d, t) and friction, we found that the friction coefficient can be used as an indicative criterion for quantitatively assessing hydrophobic or hydrophilic materials, where the borderline is roughly 2 × 105 N s m-3. That is if the water-solid friction is less than 2 × 105 N s m-3, the surface is considered hydrophobic. But if the friction is larger than this value, the surface is hydrophilic. The present findings could help to better understand fluidic transport at the nanoscale and guide the future design of functional materials, such as super-hydrophobic and super-hydrophilic surfaces by structure engineering.