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1.
Cell ; 148(1-2): 259-72, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22225612

RESUMO

Identification of the factors critical to the tumor-initiating cell (TIC) state may open new avenues in cancer therapy. Here we show that the metabolic enzyme glycine decarboxylase (GLDC) is critical for TICs in non-small cell lung cancer (NSCLC). TICs from primary NSCLC tumors express high levels of the oncogenic stem cell factor LIN28B and GLDC, which are both required for TIC growth and tumorigenesis. Overexpression of GLDC and other glycine/serine enzymes, but not catalytically inactive GLDC, promotes cellular transformation and tumorigenesis. We found that GLDC induces dramatic changes in glycolysis and glycine/serine metabolism, leading to changes in pyrimidine metabolism to regulate cancer cell proliferation. In the clinic, aberrant activation of GLDC correlates with poorer survival in lung cancer patients, and aberrant GLDC expression is observed in multiple cancer types. This link between glycine metabolism and tumorigenesis may provide novel targets for advancing anticancer therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Transformação Celular Neoplásica , Glicina Desidrogenase (Descarboxilante)/metabolismo , Neoplasias Pulmonares/metabolismo , Sequência de Aminoácidos , Antígenos CD/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Moléculas de Adesão Celular Neuronais/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Proteínas Fetais/metabolismo , Glicina/metabolismo , Humanos , Dados de Sequência Molecular , Neoplasias/enzimologia , Neoplasias/genética , Proteínas de Ligação a RNA , Alinhamento de Sequência , Serina/metabolismo , Thermus thermophilus/enzimologia , Transplante Heterólogo
2.
Proc Natl Acad Sci U S A ; 121(6): e2304619121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38289962

RESUMO

Resistance to neoadjuvant chemotherapy leads to poor prognosis of locally advanced rectal cancer (LARC), representing an unmet clinical need that demands further exploration of therapeutic strategies to improve clinical outcomes. Here, we identified a noncanonical role of RB1 for modulating chromatin activity that contributes to oxaliplatin resistance in colorectal cancer (CRC). We demonstrate that oxaliplatin induces RB1 phosphorylation, which is associated with the resistance to neoadjuvant oxaliplatin-based chemotherapy in LARC. Inhibition of RB1 phosphorylation by CDK4/6 inhibitor results in vulnerability to oxaliplatin in both intrinsic and acquired chemoresistant CRC. Mechanistically, we show that RB1 modulates chromatin activity through the TEAD4/HDAC1 complex to epigenetically suppress the expression of DNA repair genes. Antagonizing RB1 phosphorylation through CDK4/6 inhibition enforces RB1/TEAD4/HDAC1 repressor activity, leading to DNA repair defects, thus sensitizing oxaliplatin treatment in LARC. Our study identifies a RB1 function in regulating chromatin activity through TEAD4/HDAC1. It also provides the combination of CDK4/6 inhibitor with oxaliplatin as a potential synthetic lethality strategy to mitigate oxaliplatin resistance in LARC, whereby phosphorylated RB1/TEAD4 can serve as potential biomarkers to guide the patient stratification.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Oxaliplatina/farmacologia , Terapia Neoadjuvante/métodos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/genética , Quimiorradioterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cromatina , Resultado do Tratamento , Fatores de Transcrição de Domínio TEA , Ubiquitina-Proteína Ligases , Proteínas de Ligação a Retinoblastoma
3.
Proc Natl Acad Sci U S A ; 121(4): e2309881120, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38190514

RESUMO

Climate change is increasing the frequency and severity of short-term (~1 y) drought events-the most common duration of drought-globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function-aboveground net primary production (ANPP)-was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought.


Assuntos
Secas , Ecossistema , Pradaria , Ciclo do Carbono , Mudança Climática , Receptores Proteína Tirosina Quinases
4.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38012122

RESUMO

Mild cognitive impairment is considered the prodromal stage of Alzheimer's disease. Accurate diagnosis and the exploration of the pathological mechanism of mild cognitive impairment are extremely valuable for targeted Alzheimer's disease prevention and early intervention. In all, 100 mild cognitive impairment patients and 86 normal controls were recruited in this study. We innovatively constructed the individual morphological brain networks and derived multiple brain connectome features based on 3D-T1 structural magnetic resonance imaging with the Jensen-Shannon divergence similarity estimation method. Our results showed that the most distinguishing morphological brain connectome features in mild cognitive impairment patients were consensus connections and nodal graph metrics, mainly located in the frontal, occipital, limbic lobes, and subcortical gray matter nuclei, corresponding to the default mode network. Topological properties analysis revealed that mild cognitive impairment patients exhibited compensatory changes in the frontal lobe, while abnormal cortical-subcortical circuits associated with cognition were present. Moreover, the combination of multidimensional brain connectome features using multiple kernel-support vector machine achieved the best classification performance in distinguishing mild cognitive impairment patients and normal controls, with an accuracy of 84.21%. Therefore, our findings are of significant importance for developing potential brain imaging biomarkers for early detection of Alzheimer's disease and understanding the neuroimaging mechanisms of the disease.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Conectoma , Humanos , Conectoma/métodos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Imageamento por Ressonância Magnética/métodos
5.
Proc Natl Acad Sci U S A ; 119(30): e2203503119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35867816

RESUMO

Women with polycystic ovary syndrome (PCOS) frequently experience decreased sexual arousal, desire, and sexual satisfaction. While the hypothalamus is known to regulate sexual behavior, the specific neuronal pathways affected in patients with PCOS are not known. To dissect the underlying neural circuitry, we capitalized on a robust preclinical animal model that reliably recapitulates all cardinal PCOS features. We discovered that female mice prenatally treated with anti-Müllerian hormone (PAMH) display impaired sexual behavior and sexual partner preference over the reproductive age. Blunted female sexual behavior was associated with increased sexual rejection and independent of sex steroid hormone status. Structurally, sexual dysfunction was associated with a substantial loss of neuronal nitric oxide synthase (nNOS)-expressing neurons in the ventromedial nucleus of the hypothalamus (VMH) and other areas of hypothalamic nuclei involved in social behaviors. Using in vivo chemogenetic manipulation, we show that nNOSVMH neurons are required for the display of normal sexual behavior in female mice and that pharmacological replenishment of nitric oxide restores normal sexual performance in PAMH mice. Our data provide a framework to investigate facets of hypothalamic nNOS neuron biology with implications for sexual disturbances in PCOS.


Assuntos
Óxido Nítrico Sintase Tipo I , Óxido Nítrico , Síndrome do Ovário Policístico , Comportamento Sexual , Núcleo Hipotalâmico Ventromedial , Animais , Hormônio Antimülleriano/farmacologia , Modelos Animais de Doenças , Feminino , Preferência de Acasalamento Animal , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Síndrome do Ovário Policístico/enzimologia , Síndrome do Ovário Policístico/fisiopatologia , Núcleo Hipotalâmico Ventromedial/efeitos dos fármacos , Núcleo Hipotalâmico Ventromedial/metabolismo
6.
Proc Natl Acad Sci U S A ; 119(31): e2201376119, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35878022

RESUMO

Relapse to anti-HER2 monoclonal antibody (mAb) therapies, such as trastuzumab in HER2+ breast cancer (BC), is associated with residual disease progression due to resistance to therapy. Here, we identify interferon-γ inducible protein 16 (IFI16)-dependent STING signaling as a significant determinant of trastuzumab responses in HER2+ BC. We show that down-regulation of immune-regulated genes (IRG) is specifically associated with poor survival of HER2+, but not other BC subtypes. Among IRG, IFI16 is identified as a direct target of EZH2, the underexpression of which leads to deficient STING activation and downstream CXCL10/11 expression in response to trastuzumab treatment. Dual inhibition of EZH2 and histone deacetylase (HDAC) significantly activates IFI16-dependent immune responses to trastuzumab. Notably, a combination of a novel histone methylation inhibitor with an HDAC inhibitor induces complete tumor eradication and long-term T cell memory in a HER2+ BC mouse model. Our findings demonstrate an epigenetic regulatory mechanism suppressing the expression of the IFI16-CXCL10/11 signaling pathway that provides a survival advantage to HER2+ BC to confer resistance to trastuzumab treatment.


Assuntos
Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Proteínas de Membrana , Proteínas Nucleares , Fosfoproteínas , Trastuzumab , Animais , Antineoplásicos Imunológicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Quimiocina CXCL10 , Quimiocina CXCL11 , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Imunidade , Proteínas de Membrana/metabolismo , Camundongos , Recidiva Local de Neoplasia/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Receptor ErbB-2/genética , Transdução de Sinais , Trastuzumab/farmacologia
7.
BMC Genomics ; 25(1): 126, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291375

RESUMO

Copy-number variations (CNVs), which refer to deletions and duplications of chromosomal segments, represent a significant source of variation among individuals, contributing to human evolution and being implicated in various diseases ranging from mental illness and developmental disorders to cancer. Despite the development of several methods for detecting copy number variations based on next-generation sequencing (NGS) data, achieving robust detection performance for CNVs with arbitrary coverage and amplitude remains challenging due to the inherent complexity of sequencing samples. In this paper, we propose an alternative method called OTSUCNV for CNV detection on whole genome sequencing (WGS) data. This method utilizes a newly designed adaptive sequence segmentation algorithm and an OTSU-based CNV prediction algorithm, which does not rely on any distribution assumptions or involve complex outlier factor calculations. As a result, the effective detection of CNVs is achieved with lower computational complexity. The experimental results indicate that the proposed method demonstrates outstanding performance, and hence it may be used as an effective tool for CNV detection.


Assuntos
Algoritmos , Variações do Número de Cópias de DNA , Humanos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento Completo do Genoma
8.
J Hepatol ; 81(1): 93-107, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38403027

RESUMO

BACKGROUND & AIMS: The effectiveness of immune checkpoint inhibitor (ICI) therapy for hepatocellular carcinoma (HCC) is limited by treatment resistance. However, the mechanisms underlying immunotherapy resistance remain elusive. We aimed to identify the role of CT10 regulator of kinase-like (CRKL) in resistance to anti-PD-1 therapy in HCC. METHODS: Gene expression in HCC specimens from 10 patients receiving anti-PD-1 therapy was identified by RNA-sequencing. A total of 404 HCC samples from tissue microarrays were analyzed by immunohistochemistry. Transgenic mice (Alb-Cre/Trp53fl/fl) received hydrodynamic tail vein injections of a CRKL-overexpressing vector. Mass cytometry by time of flight was used to profile the proportion and status of different immune cell lineages in the mouse tumor tissues. RESULTS: CRKL was identified as a candidate anti-PD-1-resistance gene using a pooled genetic screen. CRKL overexpression nullifies anti-PD-1 treatment efficacy by mobilizing tumor-associated neutrophils (TANs), which block the infiltration and function of CD8+ T cells. PD-L1+ TANs were found to be an essential subset of TANs that were regulated by CRKL expression and display an immunosuppressive phenotype. Mechanistically, CRKL inhibits APC (adenomatous polyposis coli)-mediated proteasomal degradation of ß-catenin by competitively decreasing Axin1 binding, and thus promotes VEGFα and CXCL1 expression. Using human HCC samples, we verified the positive correlations of CRKL/ß-catenin/VEGFα and CXCL1. Targeting CRKL using CRISPR-Cas9 gene editing (CRKL knockout) or its downstream regulators effectively restored the efficacy of anti-PD-1 therapy in an orthotopic mouse model and a patient-derived organotypic tumor spheroid model. CONCLUSIONS: Activation of the CRKL/ß-catenin/VEGFα and CXCL1 axis is a critical obstacle to successful anti-PD-1 therapy. Therefore, CRKL inhibitors combined with anti-PD-1 could be useful for the treatment of HCC. IMPACT AND IMPLICATIONS: Here, we found that CRKL was overexpressed in anti-PD-1-resistant hepatocellular carcinoma (HCC) and that CRKL upregulation promotes anti-PD-1 resistance in HCC. We identified that upregulation of the CRKL/ß-catenin/VEGFα and CXCL1 axis contributes to anti-PD-1 tolerance by promoting infiltration of tumor-associated neutrophils. These findings support the strategy of bevacizumab-based immune checkpoint inhibitor combination therapy, and CRKL inhibitors combined with anti-PD-1 therapy may be developed for the treatment of HCC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Carcinoma Hepatocelular , Resistencia a Medicamentos Antineoplásicos , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Infiltração de Neutrófilos , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Animais , Humanos , Camundongos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Camundongos Transgênicos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Masculino , Quimiocina CXCL1/metabolismo , Quimiocina CXCL1/genética
9.
Nat Mater ; 22(6): 717-724, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36959500

RESUMO

Black phosphorus (BP), a fascinating semiconductor with high mobility and a tunable direct bandgap, has emerged as a candidate beyond traditional silicon-based devices for next-generation electronics and optoelectronics. The ability to grow large-scale, high-quality BP films is a prerequisite for scalable integrated applications but has thus far remained a challenge due to unmanageable nucleation events. Here we develop a sustained feedstock release strategy to achieve subcentimetre-size single-crystal BP films by facilitating the lateral growth mode under a low nucleation rate. The as-grown single-crystal BP films exhibit high crystal quality, which brings excellent field-effect electrical properties and observation of pronounced Shubnikov-de Haas oscillations, with high mobilities up to ~6,500 cm2 V-1 s-1 at low temperatures. We further extend this approach to the growth of single-crystal BP alloy films, which broaden the infrared emission regime of BP from 3.7 µm to 6.9 µm at room temperature. This work will greatly facilitate the development of high-performance electronics and optoelectronics based on BP family materials.

10.
Plant Physiol ; 191(2): 1272-1287, 2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36437699

RESUMO

Increasing planting density is one of the most effective ways to improve crop yield. However, one major factor that limits crop planting density is the weakened immunity of plants to pathogens and insects caused by dim light (DL) under shade conditions. The molecular mechanism underlying how DL compromises plant immunity remains unclear. Here, we report that DL reduces rice (Oryza sativa) resistance against brown planthopper (BPH; Nilaparvata lugens) by elevating ethylene (ET) biosynthesis and signaling in a Phytochrome B (OsPHYB)-dependent manner. The DL-reduced BPH resistance is relieved in osphyB mutants, but aggravated in OsPHYB overexpressing plants. Further, we found that DL reduces the nuclear accumulation of OsphyB, thus alleviating Phytochrome Interacting Factor Like14 (OsPIL14) degradation, consequently leading to the up-regulation of 1-Aminocyclopropane-1-Carboxylate Oxidase1 (OsACO1) and an increase in ET levels. In addition, we found that nuclear OsphyB stabilizes Ethylene Insensitive Like2 (OsEIL2) by competitively interacting with EIN3 Binding F-Box Protein (OsEBF1) to enhance ET signaling in rice, which contrasts with previous findings that phyB blocks ET signaling by facilitating Ethylene Insensitive3 (EIN3) degradation in other plant species. Thus, enhanced ET biosynthesis and signaling reduces BPH resistance under DL conditions. Our findings provide insights into the molecular mechanism of the light-regulated ET pathway and host-insect interactions and potential strategies for sustainable insect management.


Assuntos
Etilenos , Hemípteros , Oryza , Fitocromo B , Animais , Etilenos/metabolismo , Hemípteros/metabolismo , Oryza/metabolismo , Fitocromo B/genética , Fitocromo B/metabolismo
11.
Opt Lett ; 49(13): 3564-3567, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950210

RESUMO

Vectorial optical fields (VOFs) with extra degrees of freedom hold promise for many photonic applications. However, current methods to generate VOFs are either bulky in size or exhibit limited functionalities. Here, we demonstrate a tunable VOF generator by exciting plasmonic surface lattice resonances (SLRs) with axial symmetry. By meticulously arranging bilayer circular arrays with opposite handedness, we achieve a high Q-factor of 103 via just a few particles despite the general belief that too small array size suppresses the SLRs. This work presents tunable complex VOFs with distinct inhomogeneous spatial polarization distributions, which may enable various applications in integrated and polarization optics.

12.
Psychol Med ; : 1-11, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563283

RESUMO

BACKGROUND: The comorbidity between schizophrenia (SCZ) and inflammatory bowel disease (IBD) observed in epidemiological studies is partially attributed to genetic overlap, but the magnitude of shared genetic components and the causality relationship between them remains unclear. METHODS: By leveraging large-scale genome-wide association study (GWAS) summary statistics for SCZ, IBD, ulcerative colitis (UC), and Crohn's disease (CD), we conducted a comprehensive genetic pleiotropic analysis to uncover shared loci, genes, or biological processes between SCZ and each of IBD, UC, and CD, independently. Univariable and multivariable Mendelian randomization (MR) analyses were applied to assess the causality across these two disorders. RESULTS: SCZ genetically correlated with IBD (rg = 0.14, p = 3.65 × 10−9), UC (rg = 0.15, p = 4.88 × 10−8), and CD (rg = 0.12, p = 2.27 × 10−6), all surpassed the Bonferroni correction. Cross-trait meta-analysis identified 64, 52, and 66 significantly independent loci associated with SCZ and IBD, UC, and CD, respectively. Follow-up gene-based analysis found 11 novel pleiotropic genes (KAT5, RABEP1, ELP5, CSNK1G1, etc) in all joint phenotypes. Co-expression and pathway enrichment analysis illustrated those novel genes were mainly involved in core immune-related signal transduction and cerebral disorder-related pathways. In univariable MR, genetic predisposition to SCZ was associated with an increased risk of IBD (OR 1.11, 95% CI 1.07­1.15, p = 1.85 × 10−6). Multivariable MR indicated a causal effect of genetic liability to SCZ on IBD risk independent of Actinobacteria (OR 1.11, 95% CI 1.06­1.16, p = 1.34 × 10−6) or BMI (OR 1.11, 95% CI 1.04­1.18, p = 1.84 × 10−3). CONCLUSIONS: We confirmed a shared genetic basis, pleiotropic loci/genes, and causal relationship between SCZ and IBD, providing novel insights into the biological mechanism and therapeutic targets underlying these two disorders.

13.
Langmuir ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990344

RESUMO

The size or the curvature of nanoparticles (NPs) plays an important role in regulating the composition of the protein corona. However, the molecular mechanisms of how curvature affects the interaction of NPs with serum proteins still remain elusive. In this study, we employ all-atom molecular dynamics simulations to investigate the interactions between two typical serum proteins and PEGylated Au NPs with three different surface curvatures (0, 0.1, and 0.5 nm-1, respectively). The results show that for proteins with a regular shape, the binding strength between the serum protein and Au NPs decreases with increasing curvature. For irregularly shaped proteins with noticeable grooves, the binding strength between the protein and Au NPs does not change obviously with increasing curvature in the cases of smaller curvature. However, as the curvature continues to increase, Au NPs may act as ligands firmly adsorbed in the protein grooves, significantly enhancing the binding strength. Overall, our findings suggest that the impact of NP curvature on protein adsorption may be nonmonotonic, which may provide useful guidelines for better design of functionalized NPs in biomedical applications.

14.
Langmuir ; 40(2): 1295-1304, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38173387

RESUMO

The fluorinated decorations have recently been widely used in many biomedical applications. However, the potential mechanism of the fluorination effect on the cellular delivery of nanoparticles (NPs) still remains elusive. In this work, we systemically explore the penetration of a perfluoro-octanethiol-coated gold NP (PF-Au NP) and, for comparison, an octanethiol-coated gold NP (OT-Au NP) across lipid bilayers. We also investigated the effect of these two types of NPs on the properties of lipid bilayers. Our findings indicate that the lipid type and the surface tension of the lipid bilayer significantly impact the penetration capabilities of the fluorinated gold NP. By examining the distribution of ligands on the surface of the two types of NPs in water and during the penetration process, we unveil their distinct penetration characteristics. Specifically, the PF-Au NP exhibits amphiphobic behavior (both hydrophobic and lipophobic), while the OT-Au NP exhibits solely hydrophobic characteristics. Finally, we observe that the penetration capabilities can be increased by adjusting the degree of fluorination of the ligands on the NP surface. Overall, this study provides useful physical insights into the unique properties of the fluorinated decorations in NP permeation.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Bicamadas Lipídicas/química , Halogenação , Nanopartículas Metálicas/química , Nanopartículas/química , Modelos Moleculares , Ouro/química , Ligantes
15.
BMC Gastroenterol ; 24(1): 197, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877387

RESUMO

BACKGROUND: Innate/adaptive immunity is the key to anti-tumor therapy. However, its causal relationship to Gastrointestinal (GI) cancer remains unclear. METHODS: Immunity genes were extracted from the MSigDB database. The Genome-wide association studies (GWAS) summary data of GI cancer were integrated with expression quantitative trait loci (eQTL) and DNA methylation quantitative trait loci (mQTL) associated with genes. Summary-data-based Mendelian randomization (SMR) and co-localization analysis were used to reveal causal relationships between genes and GI cancer. Two-sample MR analysis was used for sensitivity analysis. Single cell analysis clarified the enrichment of genes. RESULTS: Three-step SMR analysis showed that a putative mechanism, cg17294865 CpG site regulating HLA-DRA expression was negatively associated with gastric cancer risk. HLA-DRA was significantly differentially expressed in monocyte/macrophage and myeloid cells in gastric cancer. CONCLUSION: This study provides evidence that upregulating the expression level of HLA-DRA can reduce the risk of gastric cancer.


Assuntos
Imunidade Adaptativa , Metilação de DNA , Neoplasias Gastrointestinais , Estudo de Associação Genômica Ampla , Imunidade Inata , Análise da Randomização Mendeliana , Locos de Características Quantitativas , Humanos , Imunidade Inata/genética , Imunidade Adaptativa/genética , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/imunologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/imunologia , Cadeias alfa de HLA-DR/genética , Ilhas de CpG/genética , Multiômica
16.
Artigo em Inglês | MEDLINE | ID: mdl-38981855

RESUMO

BACKGROUND AND AIM: Insomnia has been implicated in gastrointestinal diseases (GIs), but the causal effect between insomnia and GIs and underlying mechanisms remain unknown. METHODS: By using the released summary-level data, we conducted a two-step Mendelian randomization (MR) analysis to examine the relationship between insomnia and four GIs and estimate the mediating role of candidate mediators. The first step was to investigate the causal association between insomnia and GIs using univariable MR analysis. The second step was to estimate the mediation proportion of selected mediators in these associations using multivariable MR analysis. Subsequently, results from different datasets were combined using the fixed-effect meta-analysis. RESULTS: Univariable MR analysis provided strong evidence for the causal effects of insomnia on four GIs after Bonferroni correction for multiple comparisons, including peptic ulcer disease (PUD) (odds ratio [OR] = 1.15, 95% interval confidence [CI] = 1.10-1.20, P = 1.83 × 10-9), gastroesophageal reflux (GORD) (OR = 1.19, 95% CI = 1.16-1.22, P = 5.95 × 10-42), irritable bowel syndrome (IBS) (OR = 1.18, 95% CI = 1.15-1.22, P = 8.69 × 10-25), and inflammatory bowel disease (IBD) (OR = 1.09, 95% CI = 1.03-1.05, P = 3.46 × 10-3). In the mediation analysis, body mass index (BMI) and waist-to-hip ratio (WHR) were selected as mediators in the association between insomnia and PUD (BMI: mediation proportion [95% CI]: 13.61% [7.64%-20.70%]; WHR: 8.74% [5.50%-12.44%]) and GORD (BMI: 11.82% [5.94%-18.74%]; WHR: 7.68% [4.73%-11.12%]). CONCLUSIONS: Our findings suggest that genetically instrumented insomnia has causal effects on PUD, GORD, IBS, and IBD, respectively. Adiposity traits partially mediated the associations between insomnia and GIs. Further clinical studies are warranted to evaluate the protective effect of insomnia treatment on GIs.

17.
Phys Chem Chem Phys ; 26(23): 16883-16890, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38833213

RESUMO

Non-volatile magnetic random-access memories have proposed the need for spin channel switching. However, this presents a challenge as each spin channel reacts differently to the external field. Tellurene is a semiconductor with a tunable bandgap, excellent stability, and high carrier concentration, but its lack of magnetic properties has hindered its application in spintronics. In this work, the influence of an external field on transition metal (TM)-doped ß-tellurene is systematically analysed from first principles. First, the active-learning moment-tensor-potential (MTP) is used to verify the thermal stability of the V-doped system with the MTP proving to be 900 times faster than the traditional method. Subsequently, under biaxial strain ranging from -2% to 10%, the V-doped system undergoes a gradual transition from a magnetic semiconductor to a spin-gapless semiconductor, and further to a half-metal and magnetic metal. The band structure can be maintained under an electric field. By examining the magnetic anisotropy energy, the lattice changes profoundly impact the electromagnetic properties, particularly with the TMs being sensitive to strain. Moreover, the band structure is reflected in the spin resolution current of the magnetic tunnel junction. This work investigates the response of doped ß-Te to external fields, revealing its potential applications in spintronics.

18.
Phys Chem Chem Phys ; 26(18): 13751-13761, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38683175

RESUMO

Understanding the dynamics of neurotransmitters is crucial for unraveling synaptic transmission mechanisms in neuroscience. In this study, we investigated the impact of terahertz (THz) waves on the aggregation of four common neurotransmitters through all-atom molecular dynamics (MD) simulations. The simulations revealed enhanced nicotine (NCT) aggregation under 11.05 and 21.44 THz, with a minimal effect at 42.55 THz. Structural analysis further indicated strengthened intermolecular interactions and weakened hydration effects under specific THz stimulation. In addition, enhanced aggregation was observed at stronger field strengths, particularly at 21.44 THz. Furthermore, similar investigations on epinephrine (EPI), 5-hydroxytryptamine (5-HT), and γ-aminobutyric acid (GABA) corroborated these findings. Notably, EPI showed increased aggregation at 19.05 THz, emphasizing the influence of vibrational modes on aggregation. However, 5-HT and GABA, with charged or hydrophilic functional groups, exhibited minimal aggregation under THz stimulation. The present study sheds some light on neurotransmitter responses to THz waves, offering implications for neuroscience and interdisciplinary applications.


Assuntos
Simulação de Dinâmica Molecular , Neurotransmissores , Serotonina , Radiação Terahertz , Ácido gama-Aminobutírico , Neurotransmissores/química , Ácido gama-Aminobutírico/química , Serotonina/química , Serotonina/metabolismo , Nicotina/química , Epinefrina/química
19.
J Nat Prod ; 87(4): 924-934, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38513270

RESUMO

A diverse array of biologically active derivatives was derived by modifying the chemically active sites of dehydroabietylamine. Herein, we describe the synthesis of a new series of C-19-arylated dehydroabietylamine derivatives using a palladium-catalyzed C(sp3)-H activation reaction. Five analogues (3b, 3d, 3h, 3n, and 4a) exhibited antibacterial activity against Escherichia coli. Compound 4a exhibited strong inhibitory activity against DNA Topo II and Topo IV. Molecular docking modeling indicated that it can bind effectively to the target through interactions with amino acid residues. The synthesized compounds were tested in vitro for their antifungal activity against six common phytopathogenic fungi. The mechanism of action of compound 4c against Rhizoctorzia solani was investigated, revealing that it disrupts the morphology of the mycelium and enhances cell membrane permeability.


Assuntos
Abietanos , Antibacterianos , Antifúngicos , Abietanos/farmacologia , Abietanos/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Antifúngicos/farmacologia , Antifúngicos/química , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular
20.
Bioorg Chem ; 150: 107593, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38971093

RESUMO

Nitric oxide (NO) and reactive oxygen species (ROS) embody excellent potential in cancer therapy. However, as a small molecule, their targeted delivery and precise, controllable release are urgently needed to achieve accurate cancer therapy. In this paper, a novel US-responsive bifunctional molecule (SD) and hyaluronic acid-modified MnO2 nanocarrier was developed, and a US-responsive NO and ROS controlled released nanoplatform was constructed. US can trigger SD to release ROS and NO simultaneously at the tumor site. Thus, SD served as acoustic sensitizer for sonodynamic therapy and NO donor for gas therapy. In the tumor microenvironment, the MnO2 nanocarrier can effectively deplete the highly expressed GSH, and the released Mn2+ can make H2O2 to produce .OH by Fenton-like reaction, which exhibited a strong chemodynamic effect. The high concentration of ROS and NO in cancer cell can induce cancer cell apoptosis ultimately. In addition, toxic ONOO-, which was generated by the reaction of NO and ROS, can effectively cause mitochondrial dysfunction, which induced the apoptosis of tumor cells. The 131I was labeled on the nanoplatform, which exhibited internal radiation therapy for tumor therapy. In -vitro and -vivo experiments showed that the nanoplatform has enhanced biocompatibility, and efficient anti-tumor potential, and it achieves synergistic sonodynamic/NO/chemodynamic/radionuclide therapy for cancer.


Assuntos
Radioisótopos do Iodo , Compostos de Manganês , Óxido Nítrico , Óxidos , Espécies Reativas de Oxigênio , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Humanos , Animais , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Óxidos/química , Óxidos/farmacologia , Radioisótopos do Iodo/química , Apoptose/efeitos dos fármacos , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Camundongos , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Camundongos Endogâmicos BALB C , Terapia por Ultrassom , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ondas Ultrassônicas , Linhagem Celular Tumoral
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