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1.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38279650

RESUMO

As the application of large language models (LLMs) has broadened into the realm of biological predictions, leveraging their capacity for self-supervised learning to create feature representations of amino acid sequences, these models have set a new benchmark in tackling downstream challenges, such as subcellular localization. However, previous studies have primarily focused on either the structural design of models or differing strategies for fine-tuning, largely overlooking investigations into the nature of the features derived from LLMs. In this research, we propose different ESM2 representation extraction strategies, considering both the character type and position within the ESM2 input sequence. Using model dimensionality reduction, predictive analysis and interpretability techniques, we have illuminated potential associations between diverse feature types and specific subcellular localizations. Particularly, the prediction of Mitochondrion and Golgi apparatus prefer segments feature closer to the N-terminal, and phosphorylation site-based features could mirror phosphorylation properties. We also evaluate the prediction performance and interpretability robustness of Random Forest and Deep Neural Networks with varied feature inputs. This work offers novel insights into maximizing LLMs' utility, understanding their mechanisms, and extracting biological domain knowledge. Furthermore, we have made the code, feature extraction API, and all relevant materials available at https://github.com/yujuan-zhang/feature-representation-for-LLMs.


Assuntos
Biologia Computacional , Redes Neurais de Computação , Biologia Computacional/métodos , Sequência de Aminoácidos , Transporte Proteico
2.
Bioinformatics ; 40(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38806165

RESUMO

MOTIVATION: Recent advances in spatial transcriptomics allow spatially resolved gene expression measurements with cellular or even sub-cellular resolution, directly characterizing the complex spatiotemporal gene expression landscape and cell-to-cell interactions in their native microenvironments. Due to technology limitations, most spatial transcriptomic technologies still yield incomplete expression measurements with excessive missing values. Therefore, gene imputation is critical to filling in missing data, enhancing resolution, and improving overall interpretability. However, existing methods either require additional matched single-cell RNA-seq data, which is rarely available, or ignore spatial proximity or expression similarity information. RESULTS: To address these issues, we introduce Impeller, a path-based heterogeneous graph learning method for spatial transcriptomic data imputation. Impeller has two unique characteristics distinct from existing approaches. First, it builds a heterogeneous graph with two types of edges representing spatial proximity and expression similarity. Therefore, Impeller can simultaneously model smooth gene expression changes across spatial dimensions and capture similar gene expression signatures of faraway cells from the same type. Moreover, Impeller incorporates both short- and long-range cell-to-cell interactions (e.g. via paracrine and endocrine) by stacking multiple GNN layers. We use a learnable path operator in Impeller to avoid the over-smoothing issue of the traditional Laplacian matrices. Extensive experiments on diverse datasets from three popular platforms and two species demonstrate the superiority of Impeller over various state-of-the-art imputation methods. AVAILABILITY AND IMPLEMENTATION: The code and preprocessed data used in this study are available at https://github.com/aicb-ZhangLabs/Impeller and https://zenodo.org/records/11212604.


Assuntos
Transcriptoma , Transcriptoma/genética , Algoritmos , Perfilação da Expressão Gênica/métodos , Humanos , Software , Biologia Computacional/métodos , Aprendizado de Máquina , Análise de Célula Única/métodos
3.
Cancer Sci ; 115(3): 763-776, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38243657

RESUMO

Hepatocellular carcinoma (HCC) does not respond well to current treatments, even immune checkpoint inhibitors. PD-L1 (programmed cell death ligand 1 or CD274 molecule)-mediated immune escape of tumor cells may be a key factor affecting the efficacy of immune checkpoint inhibitor (ICI) therapy. However, the regulatory mechanisms of PD-L1 expression and immune escape require further exploration. Here, we observed that DDX1 (DEAD-box helicase 1) was overexpressed in HCC tissues and associated with poor prognosis in patients with HCC. Additionally, DDX1 expression correlated negatively with CD8+ T cell frequency. DDX1 overexpression significantly increased interferon gamma (IFN-γ)-mediated PD-L1 expression in HCC cell lines. DDX1 overexpression decreased IFN-γ and granzyme B production in CD8+ T cells and inhibited CD8+ T cell cytotoxic function in vitro and in vivo. In conclusion, DDX1 plays an essential role in developing the immune escape microenvironment, rendering it a potential predictor of ICI therapy efficacy in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Antígeno B7-H1/metabolismo , Carcinoma Hepatocelular/metabolismo , Linfócitos T CD8-Positivos , RNA Helicases DEAD-box/metabolismo , Interferon gama/metabolismo , Neoplasias Hepáticas/metabolismo , Microambiente Tumoral
4.
Small ; 20(2): e2305606, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670544

RESUMO

Li-rich Mn-based cathodes have been regarded as promising cathodes for lithium-ion batteries because of their low cost of raw materials (compared with Ni-rich layer structure and LiCoO2 cathodes) and high energy density. However, for practical application, it needs to solve the great drawbacks of Li-rich Mn-based cathodes like capacity degradation and operating voltage decline. Herein, an effective method of surface modification by benzene diazonium salts to build a stable interface between the cathode materials and the electrolyte is proposed. The cathodes after modification exhibit excellent cycling performance (the retention of specific capacity is 84.2% after 350 cycles at the current density of 1 C), which is mainly attributed to the better stability of the structure and interface. This work provides a novel way to design the coating layer with benzene diazonium salts for enhancing the structural stability under high voltage condition during cycling.

5.
Lipids Health Dis ; 23(1): 194, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909243

RESUMO

BACKGROUND: Lipid droplet (LD)-laden microglia is a key pathological hallmark of multiple sclerosis. The recent discovery of this novel microglial subtype, lipid-droplet-accumulating microglia (LDAM), is notable for increased inflammatory factor secretion and diminished phagocytic capability. Lipophagy, the autophagy-mediated selective degradation of LDs, plays a critical role in this context. This study investigated the involvement of microRNAs (miRNAs) in lipophagy during demyelinating diseases, assessed their capacity to modulate LDAM subtypes, and elucidated the potential underlying mechanisms involved. METHODS: C57BL/6 mice were used for in vivo experiments. Two weeks post demyelination induction at cervical level 4 (C4), histological assessments and confocal imaging were performed to examine LD accumulation in microglia within the lesion site. Autophagic changes were observed using transmission electron microscopy. miRNA and mRNA multi-omics analyses identified differentially expressed miRNAs and mRNAs under demyelinating conditions and the related autophagy target genes. The role of miR-223 in lipophagy under these conditions was specifically explored. In vitro studies, including miR-223 upregulation in BV2 cells via lentiviral infection, validated the bioinformatics findings. Immunofluorescence staining was used to measure LD accumulation, autophagy levels, target gene expression, and inflammatory mediator levels to elucidate the mechanisms of action of miR-223 in LDAM. RESULTS: Oil Red O staining and confocal imaging revealed substantial LD accumulation in the demyelinated spinal cord. Transmission electron microscopy revealed increased numbers of autophagic vacuoles at the injury site. Multi-omics analysis revealed miR-223 as a crucial regulatory gene in lipophagy during demyelination. It was identified that cathepsin B (CTSB) targets miR-223 in autophagy to integrate miRNA, mRNA, and autophagy gene databases. In vitro, miR-223 upregulation suppressed CTSB expression in BV2 cells, augmented autophagy, alleviated LD accumulation, and decreased the expression of the inflammatory mediator IL-1ß. CONCLUSION: These findings indicate that miR-223 plays a pivotal role in lipophagy under demyelinating conditions. By inhibiting CTSB, miR-223 promotes selective LD degradation, thereby reducing the lipid burden and inflammatory phenotype in LDAM. This study broadens the understanding of the molecular mechanisms of lipophagy and proposes lipophagy induction as a potential therapeutic approach to mitigate inflammatory responses in demyelinating diseases.


Assuntos
Autofagia , Catepsina B , Doenças Desmielinizantes , Gotículas Lipídicas , Lisofosfatidilcolinas , Camundongos Endogâmicos C57BL , MicroRNAs , Microglia , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Microglia/metabolismo , Microglia/patologia , Camundongos , Gotículas Lipídicas/metabolismo , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/patologia , Catepsina B/metabolismo , Catepsina B/genética , Lisofosfatidilcolinas/metabolismo , Modelos Animais de Doenças , Masculino , Regulação da Expressão Gênica , Linhagem Celular
6.
J Lipid Res ; 64(6): 100390, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209828

RESUMO

Several epidemiological studies suggest a correlation between eating time and obesity. Night eating syndrome characterized by a time-delayed eating pattern is positively associated with obesity in humans as well as in experimental animals. Here, we show that oil intake at night significantly makes more fat than that at day in wild-type mice, and circadian Period 1 (Per1) contributes to this day-night difference. Per1-knockout mice are protected from high-fat diet-induced obesity, which is accompanied by a reduction in the size of the bile acid pool, and the oral administration of bile acids restores fat absorption and accumulation. We identify that PER1 directly binds to the major hepatic enzymes involved in bile acid synthesis such as cholesterol 7alpha-hydroxylase and sterol 12alpha-hydroxylase. A biosynthesis rhythm of bile acids is accompanied by the activity and instability of bile acid synthases with PER1/PKA-mediated phosphorylation pathways. Both fasting and high fat stress enhance Per1 expression, increasing the fat absorption and accumulation. Our findings reveal that Per1 is an energy regulator and controls daily fat absorption and accumulation. Circadian Per1 controls daily fat absorption and accumulation, suggesting Per1 is a potential candidate of a key regulator in stress response and the relevant obesity risk.


Assuntos
Ácidos e Sais Biliares , Ligases , Animais , Camundongos , Ácidos e Sais Biliares/metabolismo , Colesterol 7-alfa-Hidroxilase/metabolismo , Ligases/metabolismo , Fígado/metabolismo , Obesidade/metabolismo , Proteínas Circadianas Period/metabolismo , Fosforilação , Fatores de Transcrição/metabolismo
7.
J Biol Chem ; 298(6): 101968, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35460695

RESUMO

Iron accumulates with age in mammals, and its possible implications in altering metabolic responses are not fully understood. Here, we report that both high-iron diet and advanced age in mice consistently altered gene expression of many pathways, including those governing the oxidative stress response and the circadian clock. We used a metabolomic approach to reveal similarities between metabolic profiles and the daily oscillation of clock genes in old and iron-overloaded mouse livers. In addition, we show that phlebotomy decreased iron accumulation in old mice, partially restoring the metabolic patterns and amplitudes of the oscillatory expression of clock genes Per1 and Per2. We further identified that the transcriptional regulation of iron occurred through a reduction in AMP-modulated methylation of histone H3K9 in the Per1 and H3K4 in the Per2 promoters, respectively. Taken together, our results indicate that iron accumulation with age can affect metabolic patterns and the circadian clock.


Assuntos
Envelhecimento/patologia , Código das Histonas , Proteínas Circadianas Period/genética , Monofosfato de Adenosina , Envelhecimento/metabolismo , Animais , Relógios Circadianos , Ritmo Circadiano , Expressão Gênica , Histonas/metabolismo , Ferro , Mamíferos , Metilação , Camundongos , Fatores de Transcrição/genética
8.
Breast Cancer Res Treat ; 200(1): 151-162, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37199805

RESUMO

PURPOSE: Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer. Oncogenic PELP1 is frequently overexpressed in TNBC, and it has been demonstrated that PELP1 signaling is essential for TNBC progression. The therapeutic utility of targeting PELP1 in TNBC, however, remains unknown. In this study, we investigated the effectiveness of SMIP34, a recently developed PELP1 inhibitor for the treatment of TNBC. METHODS: To ascertain the impact of SMIP34 treatment, we used seven different TNBC models for testing cell viability, colony formation, invasion, apoptosis, and cell cycle analysis. Western blotting and RT-qPCR were used to determine the mechanistic insights of SMIP34 action. Using xenograft and PDX tumors, the ability of SMIP34 in suppressing proliferation was examined both ex vivo and in vivo. RESULTS: TNBC cells' viability, colony formation, and invasiveness were all decreased by SMIP34 in in vitro cell-based assays, while apoptosis was increased. SMIP34 treatment promoted the degradation of PELP1 through the proteasome pathway. RT-qPCR analyses confirmed that SMIP34 treatment downregulated PELP1 target genes. Further, SMIP34 treatment substantially downregulated PELP1 mediated extranuclear signaling including ERK, mTOR, S6 and 4EBP1. Mechanistic studies confirmed downregulation of PELP1 mediated ribosomal biogenesis functions including downregulation of cMyc and Rix complex proteins LAS1L, TEX-10, and SENP3. The proliferation of TNBC tumor tissues was decreased in explant experiments by SMIP34. Additionally, SMIP34 treatment markedly decreased tumor progression in both TNBC xenograft and PDX models. CONCLUSIONS: Together, these findings from in vitro, ex vivo, and in vivo models show that SMIP34 may be a useful therapeutic agent for inhibiting PELP1 signaling in TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Correpressoras , Cisteína Endopeptidases/metabolismo , Transdução de Sinais , Fatores de Transcrição , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
9.
Small ; 19(33): e2301444, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37086140

RESUMO

Due to the scarce of lithium resources, potassium-ion batteries (PIBs) have attracted extensive attention due to their similar electrochemical properties to lithium-ion batteries (LIBs) and more abundant potassium resources. Even though there is considerable progress in SbBi alloy anode for LIBs and PIBs, most studies are focused on the morphology/structure tuning, while the inherent physical features of alloy composition's effect on the electrochemical performance are rarely investigated. Herein, combined the nanonization, carbon compounding, and alloying with composition regulation, the anode of nitrogen-doped carbon-coated Sbx Bi1-x (Sbx Bi1-x @NC) with a series of tuned chemical compositions is designed as an ideal model. The density functional theory (DFT) calculation and experimental investigation results show that the K+ diffusion barrier is lower and the path is easier to carry out when element Bi dominates the potassiation reaction, which is also the reason for better circulation. The optimized Sb0.25 Bi0.75 @NC shows an excellent cycling performance with a reversible specific capacity of 301.9 mA h g-1 after 500 cycles at 0.1 A g-1 . Meanwhile, the charge-discharge mechanism is intuitively invetigated and analyzed by in situ X-ray diffraction (XRD) and transmission electron microscopy (TEM) in detail. Such an alloy-type anode synthesis approach and in situ observation method provide an adjustable strategy for the designing and investigating of PIB anodes.

10.
J Synchrotron Radiat ; 30(Pt 6): 1054-1063, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37860938

RESUMO

Recently, a novel approach has been proposed to produce ultrashort, fully coherent high-repetition-rate EUV and X-ray radiation by combining an energy recovery linac (ERL) with the angular-dispersion-induced microbunching methodology. It is critical to maintain microbunching when the beam passes through bending magnets between the undulators, which results in difficulties supporting multiple beamlines. In this paper, the design of a multiplexed emitting system consisting of multi-bend achromats, matching sections and radiators to facilitate the multi-beamline operation is presented. Theoretical analysis and numerical simulations have been carried out and the results show that the microbunching and beam quality can be well maintained after four times of bending. Five radiation pulses with a central wavelength of 13.5 nm and peak power at the MW level have been produced by the same electron beam via this multiplexed emitting system. The proposed method holds potential in the multi-beamline operation of ERL- or storage-ring-based coherent light sources.

11.
BMC Cancer ; 23(1): 1185, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049741

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a major health concern, necessitating a deeper understanding of its prognosis and underlying mechanisms. This study aimed to investigate the mechanism and prognostic value of CD8+ T Cell exhaustion (CD8+ TEX)-related genes in HCC and construct a survival prognosis prediction model for patients with HCC. METHODS: CD8+ TEX-related genes associated with HCC prognosis were analysed and identified, and a prognostic prediction model was constructed using the 'least absolute shrinkage and selection operator' Cox regression model. Immunohistochemistry was used to verify the expression of the model genes in HCC tissues. A nomogram was constructed based on risk scores and clinical features, and its predictive efficacy was verified. The expression of STAM, ANXA5, and MAD2L2 in HCC cell lines was detected by western blotting; subsequently, these genes were knocked down in HCC cell lines by small interfering RNA, and their effects on the proliferation and migration of HCC cell lines were detected by colony formation assay, cck8, wound healing, and transwell assays. RESULTS: Six genes related to CD8+ TEX were included in the risk-prediction model. The prognosis of patients with HCC in the low-risk group was significantly better than that of those in the high-risk group. Cox regression analysis revealed that the risk score was an independent risk factor for the prognosis of patients with HCC. The differentially expressed genes in patients with high-risk HCC were mainly enriched in the nucleotide-binding oligomerization domain-containing protein-like receptor, hypoxia-inducible factor-1, and tumour programmed cell death protein (PD)-1/PD-L1 immune checkpoint pathways. The CD8+ TEX-related genes STAM, ANXA5, and MAD2L2 were knocked down in HCC cell lines to significantly inhibit cell proliferation and migration. The prediction results of the nomogram based on the risk score showed a good fit and application value. CONCLUSION: The prediction model based on CD8+ TEX-related genes can predict the prognosis of HCC and provide a theoretical basis for the early identification of patients with poor HCC prognosis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Exaustão das Células T , Neoplasias Hepáticas/genética , Genes cdc , Anexina A5 , Linfócitos T CD8-Positivos , Prognóstico , Proteínas Mad2
12.
J Therm Biol ; 114: 103563, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37344025

RESUMO

Thermal burn injury is a severe and life-threatening form of trauma that presents a significant challenge to clinical therapy. Therapeutic hypothermia has been shown to be beneficial in various human pathologies. Adenosine triphosphate (ATP) induces a hypothermic state that resembles hibernation-like suspended animation in mammals. This study investigates the potential protective role of ATP-induced hypothermia in thermal burn injury. Male C57BL/6 mice underwent a sham procedure or third-degree burn, and ATP-induced hypothermia was applied immediately or 1 h after burn injury. Our results show that ATP-induced hypothermia significantly improved burn depth progression and reduced collagen degradation. Moreover, hypothermia induced by ATP alleviated burn-induced hyperinflammatory responses and oxidative stress. Metabolomic profiling revealed that ATP-induced hypothermia reversed the shifts of metabolic profiles of the skin in burn mice. In addition, ATP-induced hypothermia relieved nociceptive and inflammatory pain, as observed in the antinociceptive test. Our findings suggest that ATP-induced hypothermia attenuates burn injury and provides new insights into first-aid therapy after thermal burn injury.


Assuntos
Queimaduras , Hipotermia Induzida , Hipotermia , Animais , Masculino , Camundongos , Trifosfato de Adenosina , Queimaduras/complicações , Queimaduras/terapia , Hipotermia/terapia , Hipotermia Induzida/métodos , Mamíferos , Camundongos Endogâmicos C57BL , Dor
13.
Int J Mol Sci ; 24(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37686219

RESUMO

Digital PCR (dPCR) has great potential for assessing gene editing or gene mutation due to its ability to independently inspect each DNA template in parallel. However, current dPCR methods use a fluorescence-labeled probe to detect gene variation events, and their ability to distinguish variated sequences from the wild-type sequence is limited by the probe's tolerance to mismatch. To address this, we have developed a novel dPCR method that uses a primer instead of a probe to sense gene variation. The enhanced Taq DNA polymerase in the PCR system has a high mismatch sensitivity, which enables our dPCR method to distinguish gene mutations from wild-type sequences. Compared to current dPCR methods, our method shows superior precision in assessing gene editing efficiency and single-base DNA mutation. This presents a promising opportunity to advance gene editing research and rare gene mutation detection.


Assuntos
Reação em Cadeia da Polimerase , Replicação do DNA , Corantes Fluorescentes , Edição de Genes , Mutação , Reação em Cadeia da Polimerase/métodos
14.
Breast Cancer Res ; 24(1): 26, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395812

RESUMO

BACKGROUND: Methyltransferase SETDB1 is highly expressed in breast cancer (BC), however, the mechanisms by which SETDB1 promotes BC progression to endocrine therapy resistance remains elusive. In this study, we examined the mechanisms by which SETDB1 contribute to BC endocrine therapy resistance. METHODS: We utilized therapy sensitive (MCF7 and ZR75), therapy resistant (MCF7-TamR, MCF7-FR, MCF7-PELP1cyto, MCF7-SETDB1) estrogen receptor alpha positive (ER+)BC models and conducted in vitro cell viability, colony formation, 3-dimensional cell growth assays to investigate the role of SETDB1 in endocrine resistance. RNA-seq of parental and SETDB1 knock down ER+ BC cells was used to identify unique pathways. SETDB1 interaction with PELP1 was identified by yeast-two hybrid screen and confirmed by immunoprecipitation and GST-pull down assays. Mechanistic studies were conducted using Western blotting, reporter gene assays, RT-qPCR, and in vitro methylation assays. Xenograft assays were used to establish the role of PELP1 in SETDB1 mediated BC progression. RESULTS: RNA-seq analyses showed that SETDB1 regulates expression of a subset of estrogen receptor (ER) and Akt target genes that contribute to endocrine therapy resistance. Importantly, using yeast-two hybrid screen, we identified ER coregulator PELP1 as a novel interacting protein of SETDB1. Biochemical analyses confirmed SETDB1 and PELP1 interactions in multiple BC cells. Mechanistic studies confirmed that PELP1 is necessary for SETDB1 mediated Akt methylation and phosphorylation. Further, SETDB1 overexpression promotes tamoxifen resistance in BC cells, and PELP1 knockdown abolished these effects. Using xenograft model, we provided genetic evidence that PELP1 is essential for SETDB1 mediated BC progression in vivo. Analyses of TCGA datasets revealed SETDB1 expression is positively correlated with PELP1 expression in ER+ BC patients. CONCLUSIONS: This study suggests that the PELP1/SETDB1 axis play an important role in aberrant Akt activation and serves as a novel target for treating endocrine therapy resistance in breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Proteínas Correpressoras/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/farmacologia , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Tamoxifeno/farmacologia , Fatores de Transcrição/genética
15.
Small ; 18(13): e2105958, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35362270

RESUMO

Shape memory polymers (SMPs) are a class of smart materials that change shape when stimulated by environmental stimuli. Different from the shape memory effect at the macro level, the introduction of micro-patterning technology into SMPs strengthens the exploration of the shape memory effect at the micro/nano level. The emergence of shape memory micro/nano patterns provides a new direction for the future development of smart polymers, and their applications in the fields of biomedicine/textile/micro-optics/adhesives show huge potential. In this review, the authors introduce the types of shape memory micro/nano patterns, summarize the preparation methods, then explore the imminent and potential applications in various fields. In the end, their shortcomings and future development direction are also proposed.


Assuntos
Polímeros , Têxteis
16.
FASEB J ; 35(7): e21735, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34143440

RESUMO

Neuroinflammation is recognized as a hallmark of spinal cord injury (SCI). Although neuroinflammation is an important pathogenic factor that leads to secondary injuries after SCI, neuroprotective anti-inflammatory treatments remain ineffective in the management of SCI. Moreover, the molecular signatures involved in the pathophysiological changes that occur during the course of SCI remain ambiguous. The current study investigated the proteins and pathways involved in C5 spinal cord hemi-contusion injury using a rat model by means of 4-D label-free proteomic analysis. Furthermore, two Gene Expression Omnibus (GEO) transcriptomic datasets, Western blot assays, and immunofluorescent staining were used to validate the expression levels and localization of dysregulated proteins. The present study observed that the rat models of SCI were associated with the enrichment of proteins related to the complement and coagulation cascades, cholesterol metabolism, and lysosome pathway throughout the acute and subacute phases of injury. Intriguingly, the current study also observed that 75 genes were significantly altered in both the GEO datasets, including ANXA1, C1QC, CTSZ, GM2A, GPNMB, and PYCARD. Further temporal clustering analysis revealed that the continuously upregulated protein cluster was associated with immune response, lipid regulation, lysosome pathway, and myeloid cells. Additionally, five proteins were further validated by means of Western blot assays and the immunofluorescent staining showed that these proteins coexisted with the F4/80+ reactive microglia and infiltrating macrophages. In conclusion, the proteomic data pertaining to the current study indicate the notable proteins and pathways that may be novel therapeutic targets for the treatment of SCI.


Assuntos
Contusões/metabolismo , Inflamação/metabolismo , Neurônios/metabolismo , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/metabolismo , Animais , Biologia Computacional/métodos , Modelos Animais de Doenças , Imunidade/fisiologia , Macrófagos/metabolismo , Masculino , Microglia/metabolismo , Células Mieloides/metabolismo , Proteômica/métodos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia
17.
J Gastroenterol Hepatol ; 37(4): 700-713, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35030640

RESUMO

BACKGROUND AND AIM: Colorectal cancer (CRC) is one of the major health issues in the world. Circ_0000677 has been shown to be upregulated in CRC with unclarified function and mechanism. Methyltransferase-like 3 (METTL3) acts as a regulator for gene expression via the mechanism of RNA N6 -methyladenosine (m6 A) in different types of cancer, which is under the control of SUMO1-based SUMOylation. We aim to investigate their roles in CRC progression. METHODS: Quantitative real-time polymerase chain reaction and Western blot were used to detect the expressions of METTL3, circ_0000677, and ATP binding cassette subfamily c member 1(ABCC1) in CRC patients' tissues and cell lines. The functions of ABCC1 and circ_0000677 in CRC were studied by manipulating their level via knocking down or overexpression. RNA pull-down and RNA immunoprecipitation assays were performed to identify the specific binding of target genes. The biological function of SUMOylation of METTL3 was investigated in vivo by xenograft mice tumor model. RESULTS: METTL3, circ_0000677, and ABCC1 were upregulated in CRC patients' samples and cell lines. Circ_0000677 positively regulates CRC cell proliferation and drug resistance via affecting ABCC1 expression. METTL3 facilitated circ_0000677 level via m6 A modification. METTL3 was regulated by SUMO1-mediated SUMOylation in CRC. Mutation of METTL3-K459 could suppress tumor growth in vivo via regulating circ_0000677/ABCC1 axis. CONCLUSIONS: Overall, our study revealed that circ_0000677 and its downstream target ABCC1 were upregulated in CRC cells, induced by the METTL3-mediated m6 A modification of circ_0000677 and SUMO1-mediated SUMOylation of METTL3. This work provided a new strategy for the therapeutic treatment of CRC.


Assuntos
Neoplasias Colorretais , Metiltransferases , Animais , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Humanos , Metiltransferases/genética , Camundongos , Sumoilação/genética
18.
J Cell Mol Med ; 25(14): 6535-6549, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34046994

RESUMO

Mounting data have shown that long non-coding RNAs (lncRNAs) widely participate in tumour initiation, development, progression and glycolysis in a variety of tumours. However, the clinical prognosis and molecular mechanisms of TMEM161B-AS1 in oesophageal squamous cell carcinoma (ESCC) remain still unknown. Here, TMEM161B-AS1 and HIF1AN were significantly lower in ESCC tissues than in normal samples, and their low expressions were both related to TNM stage, lymph node metastasis and poor prognosis of ESCC patients. Functionally, TMEM161B-AS1 overexpression or miR-23a-3p depletion suppressed the proliferation, invasion and glycolysis as well as reduced glucose consumption and lactate production in ESCC cells. Mechanistically, TMEM161B-AS1 manipulated HIF1AN expression by competitively sponging miR-23a-3p in ESCC cells. MiR-23a-3p mimic and HIF1AN siRNA partly reversed cell phenotypes mediated by TMEM161B-AS1 in ESCC cells. Collectively, TMEM161B-AS1, miR-23a-3p and HIF1AN may be tightly involved in ESCC development and progression as well as patients' prognosis, and TMEM161B-AS1/miR-23a-3p/HIF1AN signal axis may be a promising target for the treatment of ESCC patients.


Assuntos
Carcinoma de Células Escamosas do Esôfago/genética , Proteínas de Membrana/genética , MicroRNAs/genética , Oxigenases de Função Mista/genética , RNA Longo não Codificante/genética , Proteínas Repressoras/genética , Idoso , Idoso de 80 Anos ou mais , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Glicólise/genética , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Transdução de Sinais
19.
Breast Cancer Res Treat ; 185(2): 343-357, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33057995

RESUMO

PURPOSE: Cancer stem cells (CSCs) are highly tumorigenic, spared by chemotherapy, sustain tumor growth, and are implicated in tumor recurrence after conventional therapies in triple negative breast cancer (TNBC). Lysine-specific histone demethylase 1A (KDM1A) is highly expressed in several human malignancies and CSCs including TNBC. However, the precise mechanistic role of KDM1A in CSC functions and therapeutic utility of KDM1A inhibitor for treating TNBC is poorly understood. METHODS: The effect of KDM1A inhibition on cell viability, apoptosis, and invasion were examined by Cell Titer Glo, Caspase 3/7 Glo, and matrigel invasion assays, respectively. Stemness and self-renewal of CSCs were examined using mammosphere formation and extreme limiting dilution assays. Mechanistic studies were conducted using RNA-sequencing, RT-qPCR, Western blotting and reporter gene assays. Mouse xenograft and patient derived xenograft models were used for preclinical evaluation of KDM1A inhibitor. RESULTS: TCGA data sets indicated that KDM1A is highly expressed in TNBC. CSCs express high levels of KDM1A and inhibition of KDM1A reduced the CSCs enrichment in TNBC cells. KDM1A inhibition reduced cell viability, mammosphere formation, self-renewal and promoted apoptosis of CSCs. Mechanistic studies suggested that IL6-JAK-STAT3 and EMT pathways were downregulated in KDM1A knockdown and KDM1A inhibitor treated cells. Importantly, doxycycline inducible knockout of KDM1A reduced tumor progression in orthotopic xenograft models and KDM1A inhibitor NCD38 treatment significantly reduced tumor growth in patient derived xenograft (PDX) models. CONCLUSIONS: Our results establish that KDM1A inhibition mitigates CSCs functions via inhibition of STAT3 and EMT signaling, and KDM1A inhibitor NCD38 may represent a novel class of drug for treating TNBC.


Assuntos
Histona Desmetilases , Neoplasias de Mama Triplo Negativas , Animais , Linhagem Celular Tumoral , Proliferação de Células , Histona Desmetilases/antagonistas & inibidores , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Camundongos , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Opt Express ; 29(8): 12266-12277, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984990

RESUMO

Tunable high-order sideband generation has important applications in the realization of the optical frequency comb with a varying spectral region (corresponding to the sideband range) and frequency resolution (corresponding to the sideband interval). In this paper, we propose a theoretical scheme to tune both the range and the interval of the high-order sidebands in a coupled double-cavity optomechanical system, which consists of an optomechanical cavity and an auxiliary cavity. Our proposal can be realized by driving the optomechanical cavity with a control field and a probe field simultaneously, driving the auxiliary cavity with a pump field. Furthermore, we assume that the frequency detuning between the control field and the probe field (the pump field) equals ωb/n (ωb/m), where ωb is the mechanical frequency, m and n are integers. When n = m = 1, we find that the sideband range can be effectively enlarged by increasing the pump amplitude or the photon-hopping coupling rate, or by decreasing the auxiliary cavity damping rate. When n = 1 and m > 1, the output spectrum consists of a series of integer-order sidebands, fraction-order sidebands, and the sum and difference sidebands, and the sideband interval becomes ωb/m and can be diminished by simultaneously increasing m and the pump amplitude.

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