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1.
Small Methods ; : e2400195, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38699929

RESUMO

Existing RNA in situ imaging strategies mostly utilize parallel repetitive nucleic acid self-assembly to achieve multiple analysis, with limitations of complicated systems and cumbersome steps. Here, a Cas9 code key system with key probe (KP) encoder and CRISPR/Cas9 signal exporter is developed. This system triggers T-protospacer adjacent motif (T-PAM structural transitions of multiple KP encoders to form coding products with uniform single-guide RNA (sgRNA) target sequences as tandem nodes. Only single sgRNA/Cas9 complex is required to cleave multiple coding products, enabling efficient "many-to-one" tandem signaling, and non-collateral cleavage activity-dependent automatic signaling output through active introduction of mismatched bases. Compared with conventional parallel multiple signaling analysis model, the proposed system greatly simplifies reaction process and enhances detection efficiency. Further, a rapid multiple RNA in situ imaging system is developed by combining the Cas9 code key system with a T-strand displacement amplification (T-SDA) signal amplifier. The constructed system is applied to tumor cells and clinicopathology slices, generating clear multi-mRNA imaging profiles in less than an hour with just one step. Therefore, this work provides reliable technical support for clinical tumor typing and molecular mechanism investigation.

2.
Medicine (Baltimore) ; 103(8): e37264, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394486

RESUMO

This study aimed to use bioinformatics approaches for predicting the anticancer mechanisms of curcumin on triple-negative breast cancer (TNBC) and to verify these predictions through in vitro experiments. Initially, the Cell Counting Kit-8 (CCK8) assay was employed to rigorously investigate the influence of curcumin on the proliferative capacity of TNBC cells. Subsequently, flow cytometry was employed to meticulously assess the impact of curcumin on cellular apoptosis and the cell cycle regulation. Transwell assays were employed to meticulously evaluate the effect of curcumin on the motility of TNBC cells. RNA sequencing was conducted, followed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses of differentially expressed genes, aiming to elucidate the potential anticancer mechanisms underlying curcumin's effects. To thoroughly elucidate the interactions among multiple proteins, we constructed a protein-protein interaction (PPI) network. Finally, the expression levels of several key proteins, including fibronectin, mTOR, ß-Catenin, p-Akt, Akt, N-Cadherin, p-S6, and S6, were assessed using the western blot. The CCK8 assay results showed that curcumin significantly inhibited the proliferation of Hs578T and MDA-MB-231 cells. Flow cytometry results showed that curcumin induced apoptosis in these cells and arrested the cell cycle at the G2/M phase. Additionally, Transwell assay results showed that curcumin effectively reduced the motility of Hs578T and MDA-MB-231 cells. Enrichment analysis of RNA sequencing data showed that the mechanism of action of curcumin was significantly associated with signaling pathways such as pathways in cancer, focal adhesion, and PI3K-Akt signaling pathways. Subsequently, we constructed a protein-protein interaction network to elucidate the interactions among multiple proteins. Finally, Western blotting analysis showed that curcumin significantly decreased the expression levels of key proteins including Fibronectin, mTOR, ß-Catenin, p-Akt, Akt, N-Cadherin, p-S6, and S6. Curcumin exhibits its therapeutic potential in TNBC by modulating multiple signaling pathways. It may inhibit the epithelial-mesenchymal transition process by downregulating the expression of proteins involved in the mTOR and PI3K-Akt signaling pathways, thereby suppressing the motility of TNBC cells. These findings provide experimental evidence for considering curcumin as a potential therapeutic strategy in the treatment of TNBC.


Assuntos
Curcumina , Neoplasias de Mama Triplo Negativas , Humanos , beta Catenina/genética , Curcumina/farmacologia , Curcumina/uso terapêutico , Fibronectinas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proliferação de Células , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Caderinas/metabolismo , Biologia Computacional , Linhagem Celular Tumoral
3.
Aging (Albany NY) ; 16(4): 4014-4032, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38393698

RESUMO

BACKGROUND: Breast cancer (BC) is a heterogeneous tumor with a variety of etiology and clinical features. Antibody-dependent cell phagocytosis (ADCP) is the last step of immune checkpoint inhibition (ICI), and macrophages detect and recognize tumor cells, then destroy and engulf tumor cells. Despite the large number, negative regulators that inhibit phagocytic activity are still a key obstacle to the full efficacy of ICI. PATIENTS AND METHODS: An ADCP-related risk score prognostic model for risk stratification as well as prognosis prediction was established in the Cancer Genome Atlas (TCGA) cohort. The predictive value of ADCP risk score in prognosis and immunotherapy was also further validated in the TCGA along with International Cancer Genome Consortium cohorts. To promote the clinical application of the risk score, a nomogram was established, with its effectiveness verified by different methods. RESULTS: In this study, the genes collected from previous studies were defined as ADCP-related genes. In BC patients, two ADCP-related subtypes were identified. The immune characteristics and prognostic stratification were significant different between them. CONCLUSIONS: We identified two subtypes associated with ADCP gene expression in breast cancer. They have significant differences in immune cells, molecular functions, HLA family genes, immune scores, stromal scores, and inflammatory gene expression, which have important guiding significance for the selection of clinical treatment methods. At the same time, we constructed a risk model based on ADCP, and the risk score can be used as a good indicator of prognosis, providing potential therapeutic advantages for chemotherapy and immunotherapy, thus helping the clinical decision-making of BC patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Citofagocitose , Prognóstico , Anticorpos , Nomogramas , Microambiente Tumoral
4.
Anal Chem ; 96(5): 2253-2263, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38277203

RESUMO

Current study in the heterogeneity and physiological behavior of tumor cells is limited by the fluorescence in situ hybridization technology in terms of probe assembly efficiency, background suppression capability, and target compatibility. In a typically well-designed assay, hybridization probes are constructed in a confined nanostructure to achieve a rapid assembly for efficient signal response, while the excessively high local concentration between different probes inevitably leads to nonspecific background leakage. Inspired by the fabric zipper, we propose a novel confinement reaction pattern in a zipper-confined DNA nanoframe (ZCDN), where two kinds of hairpin probes are independently anchored respective tracks. The metastable states of the dual tracks can well avoid signal leakage caused by the nonspecific probe configuration change. Biomarker-mediated proximity ligation reduces the local distance of dual tracks, kinetically triggering an efficient allosteric chain reaction between the hairpin probes. This method circumvents nonspecific background leakage while maintaining a high efficiency in responding to targets. ZCDN is employed to track different cancer biomarkers located in both the cytoplasm and cytomembrane, of which the expression level and oligomerization behavior can provide crucial information regarding intratumoral heterogeneity. ZCDN exhibits high target response efficiency and strong background suppression capabilities and is compatible with various types of biological targets, thus providing a desirable tool for advanced molecular diagnostics.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Hibridização in Situ Fluorescente , DNA/química , Diagnóstico por Imagem , Nanoestruturas/química , Sondas de DNA/genética , Sondas de DNA/química , Técnicas Biossensoriais/métodos
5.
Environ Int ; 179: 108180, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37690220

RESUMO

E-cigarettes, also known as electronic nicotine delivery systems (ENDS), are mainly used among adolescents and young adults. Similar to traditional cigarettes, different concentrations of nicotine are also added to E-cigarette's liquid (E-liquid), but due to the supplementation of chemicals such as propylene glycol (PG), vegetable glycerin (VG) and flavors, it is difficult to determine the risk after using E-cigarettes. And given to the specificity of the aerosol particle composition and atomization process of E-cigarettes, it is necessary to assess the neurotoxic effects of long-term E-cigarettes use. In this study, two commercial nicotine-containing (5%) and nicotine-free E-liquids were diluted to investigate the neurobehavioral changes and addictive tendencies of developing C. elegans after sub-chronic exposure to E-liquid. The results showed that sub-chronic exposure of E-liquid could lead to impaired growth and development of nematodes, abnormal general neuromotor behavior and advanced learning and memory behavior, and nicotine-containing E-liquid could also lead to increased addiction tendency of nematodes. Although the damage effect of nicotine free E-liquid is smaller than that of the nicotine-containing group, its toxic effect cannot be ignored. Further analysis of the neurotoxicity mechanism found that redox imbalance-mediated mitochondrial stress and aging may be important causes of E-liquid-induced biological damage. The biosafety of e-cigarette aerosols was also included in the assessment. The study found that the heated atomization process did not alter the E-liquid components, and E-cigarette aerosols still have the effect of interfering with the growth and development of nematodes and neurobehavior, and its addictive nature is also of concern. This study can provide new ideas for future studies on the neurotoxic effects and safety assessment of the E-cigarettes, and provide theoretical reference for the study on the injury mechanism of E-cigarettes.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Síndromes Neurotóxicas , Adolescente , Humanos , Adulto Jovem , Animais , Caenorhabditis elegans , Nicotina/toxicidade , Aerossóis/toxicidade , Envelhecimento
6.
Retina ; 43(11): 1872-1880, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37418776

RESUMO

PURPOSE: To compare three different internal limiting membrane (ILM) peeling techniques, including standard ILM peeling, fovea-sparing ILM peeling, and inverted ILM flap (ILMF), in the treatment of myopic traction maculopathy with high risk of postoperative macular hole development. METHOD: This retrospective cohort study enrolled 101 eyes suffering from lamellar macular hole combined with myopic traction maculopathy in 98 consecutive patients who underwent vitrectomy with either standard ILM peeling, fovea-sparing ILM peeling, or ILMF from July 2017 to August 2020. All patients were followed up for at least 12 months after surgery. Best-corrected visual acuity, macular anatomical outcomes, and postoperative full-thickness macular hole (FTMH) formation were evaluated. RESULTS: No significant differences were found among the three surgical groups in baseline characteristics. 12 months after surgery, the mean best-corrected visual acuity was significantly improved ( P < 0.001) and showed no significant differences among groups ( P = 0.452). None of the eyes in the ILMF group, five eyes (15.6%) in the standard ILM peeling group, and six eyes (17.1%) in the fovea-sparing ILM peeling group developed a postoperative FTMH ( P = 0.026). Logistic regression showed that the ILM peeling technique was an independent influencing factor for FTMH formation (OR = 0.209, P = 0.014). CONCLUSION: Compared with the standard ILM peeling or fovea-sparing ILM peeling technique, the ILMF technique resulted in similar visual outcomes but a relatively low incidence of postoperative FTMH in the treatment of lamellar macular hole combined with myopic traction maculopathy. Inverted ILM flap is an effective technique for treating myopic traction maculopathy with high risk of postoperative FTMH development.


Assuntos
Membrana Epirretiniana , Degeneração Macular , Perfurações Retinianas , Humanos , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/etiologia , Perfurações Retinianas/cirurgia , Estudos Retrospectivos , Tração , Membrana Epirretiniana/etiologia , Membrana Epirretiniana/cirurgia , Membrana Basal/cirurgia , Acuidade Visual , Vitrectomia/métodos , Degeneração Macular/cirurgia , Tomografia de Coerência Óptica
7.
Signal Transduct Target Ther ; 8(1): 186, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37193687

RESUMO

Seizures due to cortical dysplasia are notorious for their poor prognosis even with medications and surgery, likely due to the widespread seizure network. Previous studies have primarily focused on the disruption of dysplastic lesions, rather than remote regions such as the hippocampus. Here, we first quantified the epileptogenicity of the hippocampus in patients with late-stage cortical dysplasia. We further investigated the cellular substrates leading to the epileptic hippocampus, using multiscale tools including calcium imaging, optogenetics, immunohistochemistry and electrophysiology. For the first time, we revealed the role of hippocampal somatostatin-positive interneurons in cortical dysplasia-related seizures. Somatostatin-positive were recruited during cortical dysplasia-related seizures. Interestingly, optogenetic studies suggested that somatostatin-positive interneurons paradoxically facilitated seizure generalization. By contrast, parvalbumin-positive interneurons retained an inhibitory role as in controls. Electrophysiological recordings and immunohistochemical studies revealed glutamate-mediated excitatory transmission from somatostatin-positive interneurons in the dentate gyrus. Taken together, our study reveals a novel role of excitatory somatostatin-positive neurons in the seizure network and brings new insights into the cellular basis of cortical dysplasia.


Assuntos
Interneurônios , Convulsões , Humanos , Interneurônios/metabolismo , Hipocampo , Somatostatina/genética , Somatostatina/metabolismo , Giro Denteado/metabolismo
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 38-43, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36861153

RESUMO

Objective To explore the risk factors of clopidogrel resistance (CR) in the elderly patients with atherosclerotic cardiovascular disease and to provide evidence for the antiplatelet therapy. Methods A total of 223 elderly patients (≥80 years old) with atherosclerotic cardiovascular disease treated in the Department of Geriatrics in the Peking University People's Hospital from January 18,2013 to November 30,2019 and meeting the inclusion criteria were enrolled in this study.The clinical data and laboratory test results were collected,including clinical disease,drug use,physical examination,complete blood cell analysis,biochemical indicators,and thromboelastogram (TEG).The rate of platelet inhibition induced by adenosine diphosphate was calculated according to the TEG.We assigned the patients into a CR group (n=84) and a control group (n=139) to analyze the incidence and influence factors of CR in the elderly patients with atherosclerotic cardiovascular disease. Results The incidence of CR was 37.7% in the elderly patients with atherosclerotic cardiovascular disease.The CR group had lower hemoglobin (t=3.533,P=0.001) and higher hypertension prevalence rate (χ2=6.581,P=0.006),proportion of multiple drugs (χ2=3.332,P=0.048),body mass index (BMI) (t=-2.181,P=0.030),total cholesterol (t=-2.264,P=0.025),triglycerides (Z=-2.937,P=0.003),low-density lipoprotein cholesterol (LDL-C) (t=-2.347,P=0.020),and proportion of women (χ2=5.562,P=0.014) than the control group.The results of multivariate Logistic regression showed that hemoglobin (OR=0.962,P<0.001),BMI (OR=1.154,P=0.003),and LDL-C (OR=1.688,P=0.018) were the factors influencing CR in the elderly patients with atherosclerotic cardiovascular disease. Conclusion Hemoglobin,BMI,and LDL-C may be independent factors associated with the occurrence of CR in the elderly patients with atherosclerotic cardiovascular disease.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , LDL-Colesterol , Clopidogrel/uso terapêutico , Fatores de Risco
9.
Nat Commun ; 14(1): 1028, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823172

RESUMO

Diffuse midline glioma-H3K27M mutant (DMG) and glioblastoma (GBM) are the most lethal brain tumors that primarily occur in pediatric and adult patients, respectively. Both tumors exhibit significant heterogeneity, shaped by distinct genetic/epigenetic drivers, transcriptional programs including RNA splicing, and microenvironmental cues in glioma niches. However, the spatial organization of cellular states and niche-specific regulatory programs remain to be investigated. Here, we perform a spatial profiling of DMG and GBM combining short- and long-read spatial transcriptomics, and single-cell transcriptomic datasets. We identify clinically relevant transcriptional programs, RNA isoform diversity, and multi-cellular ecosystems across different glioma niches. We find that while the tumor core enriches for oligodendrocyte precursor-like cells, radial glial stem-like (RG-like) cells are enriched in the neuron-rich invasive niche in both DMG and GBM. Further, we identify niche-specific regulatory programs for RG-like cells, and functionally confirm that FAM20C mediates invasive growth of RG-like cells in a neuron-rich microenvironment in a human neural stem cell derived orthotopic DMG model. Together, our results provide a blueprint for understanding the spatial architecture and niche-specific vulnerabilities of DMG and GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Adulto , Humanos , Criança , Transcriptoma/genética , Ecossistema , Células Ependimogliais , Glioma/genética , Glioma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Microambiente Tumoral/genética
10.
Front Mol Biosci ; 10: 1334083, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259687

RESUMO

Introduction: Depression is a common illness worldwide. However, the current treatments available for depression only achieve relative success, often come with several side effects, and are associated with high costs. Aurantii Fructus Immaturus (AFI) has a rich historical legacy in Traditional Chinese Medicine (TCM) for its traditional use as a treatment for depression. In this research, our primary objective is to examine the potential antidepressant properties and the mechanisms at play behind a particular bioactive compound found in AFI, which is referred to as carbon dots derived from AFI Carbonisata (AFIC-CDs). Methods: Extracted and isolated the AFIC-CDs from the decoction of AFIC, then characterized the morphological structure and functional groups comprehensively. We then utilized two distinct models to investigate the anti-depressive properties of AFIC-CDs: the chronic unpredictable mild stress (CUMS) model and the reserpine-induced pain-depression dyad model. In the CUMS model, we assessed immobile time and measured neurotransmitter levels in the mouse brain cortex. In the pain-depression dyad model, we evaluated immobile time, neurotransmitter levels, interleukin-1 (IL-1ß) and tumor necrosis factor-α (TNF-α) levels, and the expression of mRNA of brain-derived neurotrophic factor (BDNF) and tryptophan hydroxylase 2 (Tph2). Results: AFIC-CDs were found to have abundant chemical groups, and their diameter ranged from 2 to 10 nm. In the CUMS model, AFIC-CDs demonstrated significant effects. They reduced the immobile time of the mice and increased the levels of serotonin (5-HT), dopamine (DA), and norepinephrine (NE) in the mouse brain cortex. In the pain-depression dyad model, the AFIC-CDs groups decreased the immobile time, showed effect in increasing both the neurotransmitters' levels and the expression of mRNA of BDNF and Tph2, and decreased the IL-1ß and TNF-α levels in mouse brain cortex. Taken together, these results strongly indicate that AFIC-CDs possess significant antidepressant activity. Conclusion: AFIC-CDs demonstrate promising therapeutic potential in the treatment of depression, suggesting that they may become a valuable candidate for depression management. This not only extends the understanding of the biological activity of carbon dots (CDs) but also opens up new possibilities for the development of effective depression treatment strategies.

11.
Transl Vis Sci Technol ; 11(6): 18, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35727187

RESUMO

Purpose: The purpose of this study was to investigate the clinical characteristics of paravascular abnormalities (PVAs) and retinoschisis, and their associations with choroidal thickness (ChT) in young highly myopic (HM) adults. Methods: A total number of 645 eyes were included. Paravascular microfolds (PMs), paravascular cystoid spaces (PCs), paravascular lamellar holes (PLHs), and retinoschisis were detected using swept-source optical coherence tomography. Their associations with macular ChT and risk factors were analyzed. Results: PMs, PCs, and PLHs were detected in 203 (31.5%), 141 (21.9%), and 30 (4.7%) eyes, respectively. Retinoschisis was found in 50 (7.8%) eyes, 43 (86.0%) of which were located around the retinal vessels surrounding the optic disc. A decreasing trend of macular ChT (P < 0.001) was observed in the eyes with PMs only, with both PCs and PMs, and with PLHs, PCs, and PMs. After adjustments for age, sex, and axial length (AL), the presence of PCs, PLHs, or retinoschisis around the optic disc was negatively associated with macular ChT (all P < 0.05). Eyes with longer AL, incomplete posterior vitreous detachment (PVD), and myopic atrophic maculopathy (MAM) were more likely to have PCs (all P < 0.01) and retinoschisis around the optic disc (all P < 0.05). Conclusions: PVAs were observed in approximately one third of the young HM adults in this study. The presence of PCs, PLHs, or retinoschisis around the optic disc was associated with thinner macular ChT. Eyes with longer AL, incomplete PVD, and MAM may be at risk of developing PVAs and retinoschisis around the optic disc. Translational Relevance: PCs, PLHs, and retinoschisis around the optic disc could serve as early indicators for myopia progression.


Assuntos
Miopia Degenerativa , Retinosquise , Descolamento do Vítreo , Adulto , Corioide/diagnóstico por imagem , Humanos , Miopia Degenerativa/complicações , Vasos Retinianos , Retinosquise/complicações , Tomografia de Coerência Óptica/métodos , Descolamento do Vítreo/complicações
12.
Plant Cell Rep ; 41(6): 1449-1460, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35362736

RESUMO

KEY MESSAGE: EgMYB108 regulates VLCFA anabolism in oil palm. Very long-chain fatty acids (VLCFAs), which are fatty acids with more than 18 C, can not only be used as a form of triglyceride (TAG) but also provide precursors for the biosynthesis of cuticle wax, and they exist in plant epidermal cells in the form of wax in higher plants. However, which and how transcriptional factors (TFs) regulate this process is largely unknown in oil palm. In this study, a MYB transcription factor (EgMYB108) with high expression in the mesocarp of oil palm fruit was characterized. Overexpression of EgMYB108 promoted not only total lipid content but also VLCFA accumulation in oil palm embryoids. Subsequently, transient transformation in protoplasts and qRT-PCR analysis indicated that the EgKCS5 and EgLACS4 genes were significantly increased with the overexpression of EgMYB108. Furthermore, yeast one­hybrid assays, dual-luciferase assays and EMSAs demonstrated that EgMYB108 binds to the promoters of EgKCS5 and EgLACS4 and regulates their transcription. Finally, EgMYB108 interacts with the promoters of EgLACS and EgKCS simultaneously and finally improves the VLCFA and total lipid contents; a pathway summarizing this interaction was depicted.. The results provide new insight into the mechanism by which EgMYB108 regulates lipid and VLCFA accumulation in oil palm.


Assuntos
Arecaceae , Arecaceae/genética , Arecaceae/metabolismo , Ácidos Graxos/metabolismo , Frutas/genética , Frutas/metabolismo , Óleo de Palmeira/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triglicerídeos/metabolismo
13.
ACS Omega ; 6(37): 23643-23653, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34568644

RESUMO

In this paper, the brief development of chemical kinetic modeling of natural gas is discussed, with emphasis on the development of chemical kinetic mechanisms describing fuel oxidation. The addition of ethane and/or propane to natural gas not only decreases the ignition delay times but also increases flame speeds. Thus, the mixture of methane, ethane, and propane rather than bare methane obtains more accurate predictions for the combustion and emission characteristics of natural gas. This paper also evaluates different comprehensive mechanisms employed for natural gas engines and pointed out their advantages and disadvantages, giving guidance for the selection of mechanisms during the development of natural gas engines.

14.
Nat Commun ; 12(1): 2024, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795666

RESUMO

The end-Permian mass extinction (EPME) was the most severe extinction event in the past 540 million years, and the Siberian Traps large igneous province (STLIP) is widely hypothesized to have been the primary trigger for the environmental catastrophe. The killing mechanisms depend critically on the nature of volatiles ejected during STLIP eruptions, initiating about 300 kyr before the extinction event, because the atmosphere is the primary interface between magmatism and extinction. Here we report Ni isotopes for Permian-Triassic sedimentary rocks from Arctic Canada. The δ60Ni data range from -1.09‰ to 0.35‰, and exhibit the lightest δ60Ni compositions ever reported for sedimentary rocks. Our results provide strong evidence for global dispersion and loading of Ni-rich aerosol particles into the Panthalassic Ocean. Our data demonstrate that environmental degradation had begun well before the extinction event and provide a link between global dispersion of Ni-rich aerosols, ocean chemistry changes, and the EPME.

15.
Sci Total Environ ; 772: 145475, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33770885

RESUMO

Electronic cigarettes (E-cigarette) are an alternative for traditional cigarette smokers to quit smoking. Based on the current understanding, electronic cigarettes have rapidly become popular among existing smokers and former non-smokers. However, increasing research at different levels reveals that e-cigarettes are unsafe. This review provides an overview of the toxicology of e-cigarettes based on existing in vivo and in vitro studies and compares their toxicity with that of traditional cigarettes. Moreover, we describe the associated toxicity components in e-cigarettes, as well as the potential mechanism by which e-cigarettes exert toxic effects. As is known to all, the nicotine in traditional cigarettes and e-cigarettes has certain toxicity. Besides, a few studies have shown that propylene glycol and vegetable glycerin mixture and flavoring agents in e-cigarettes also are the key components causing adverse effects in animals or cells. There is insufficient scientific evidence on the toxicity of e-cigarettes due to the lack of standardized research methods, prompting the need to conduct a comprehensive toxicity assessment of e-cigarette toxicity to elucidate the safety issues of e-cigarettes. Eventually, a basis for decision-making on whether people use e-cigarettes will be obtained.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Animais , Glicerol , Nicotina/toxicidade , Fumar
16.
J Plant Physiol ; 253: 153273, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32927134

RESUMO

Global warming has multifarious effects on crop growth and productivity. Nonetheless, the effects of moderate-high temperatures and melatonin on tea yield and quality remain unclear. In this study, we found that melatonin, a universal growth stimulatory molecule, not only promotes photosynthesis and biomass accumulation in tea plants (Camellia sinensis L.) but also improves tea quality under sub high temperature (SHT). SHT increased the dry biomass and photosynthesis by 40.8% and 28.1%, respectively, and exogenous melatonin caused a further improvement. Moreover, SHT increased the total polyphenol concentrations and decreased the free amino acid concentrations, leading to a significant increase (68.2%) in polyphenol to free amino acid ratio. However, melatonin decreased the polyphenol to free amino acid ratio by delicately improving the concentrations of polyphenols and amino acids. Consistent with the total polyphenol, melatonin increased the concentrations of (-)-catechin, (-)-gallocatechin (GC), and (-)-epigallocatechin-3-gallate (EGCG) in tea leaves. The qRT-PCR analysis revealed that melatonin increased the transcript levels of catechins biosynthesis genes, such as CsCHS, CsCH1, CsF3H, CsDFR, CsANS, CsLAR, and CsANR under SHT. Meanwhile, the theanine concentration was decreased by SHT, which was attributed to the attenuated expression of CsGS, CsGOGAT, CsGDH, and CsTS1. Nonetheless, melatonin significantly increased those transcripts and the content of theanine under SHT. Melatonin also increased the caffeine content by inducing the expression of CsTIDH, CssAMS, and CsTCS1. These results suggest that melatonin could positively alter tea growth and quality by modulating the photosynthesis and biosynthesis of polyphenols, amino acids, and caffeine in tea leaves under SHT.


Assuntos
Camellia sinensis/efeitos dos fármacos , Catequina/análogos & derivados , Glutamatos/biossíntese , Melatonina/farmacologia , Fotossíntese/efeitos dos fármacos , Cafeína/metabolismo , Camellia sinensis/genética , Camellia sinensis/fisiologia , Catequina/biossíntese , Clima , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/fisiologia , Chá/efeitos dos fármacos , Chá/normas , Temperatura
17.
Mol Med Rep ; 19(5): 3963-3971, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30942418

RESUMO

Histone arginine methylation is a universal post­translational modification that has been implicated in multiple cellular and sub­cellular processes, including pre­mRNA splicing, DNA damage signaling, mRNA translation, cell signaling and cell death. Despite these important roles, the understanding of its regulation with respect to certain other modifications, such as phosphorylation and acetylation, is very poor. Thus far, few histone arginine demethylases have been identified in mammalian cells, compared with nine protein arginine methyltransferases (PRMTs) that have been reported. Studies have reported that aberrant histone arginine methylation is strongly associated with carcinogenesis and metastasis. This increases the requirement for understanding the regulation of histone arginine demethylation. The present review summarizes the published studies and provides further insights into histone arginine methylases and demethylases.


Assuntos
Histona Desmetilases/metabolismo , Histonas/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Dano ao DNA , Histona Desmetilases/química , Humanos , Metilação , Proteína-Arginina N-Metiltransferases/química , Transdução de Sinais
18.
Mol Genet Genomic Med ; 7(6): e677, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30968603

RESUMO

BACKGROUND: Breast cancer is the most common cancer among women worldwide. Here, we report the prevalence of BRCA1/2 mutations in patients with high-risk breast cancer from Inner Mongolia and Jilin, China, which was a part of a nationwide project on the detection of BRCA1/2 mutations in Chinese patients with hereditary breast cancer. METHODS: According to the criteria, index patients from a total of 245 independent families were initially recruited. All 49 exons of BRCA1 and BRCA2 and adjacent noncoding regions were screened for mutations based on next-generation sequencing from collected saliva. RESULTS: We detected 17 BRCA1/2 variants in 18 of 216 (8.3%) index patients with high-risk breast cancer. Among these, seven mutations were novel, including four BRCA1 mutations (c.123_124delCAinsAT, c.5093_5096delCTAA, c.5396-2A>G, and c.2054delinsGAAGAGTAACAAGTAAGAAGAGTAACAAGAAG), and three BRCA2 mutations (c.304A>T, c.7552_7553insT, and c.9548_9549insA). The BRCA1/2 variants were identified in 14% (8/57) of the patients with triple-negative breast cancer and in 6.3% (10/159) of the patients with non-triple-negative breast cancer. There was no significant difference between the two groups (p = 0.07). A higher frequency for BRCA1 mutations was observed in patients with triple-negative breast cancer than in those with non-triple-negative breast cancer (12.3% vs. 2.5%, p = 0.004). The frequencies of the BRCA2 mutations were not significantly different between patients with triple-negative breast cancer and those with non-triple-negative breast cancer (1.8% vs. 3.8%, p = 0.46). CONCLUSION: We found that patients with triple-negative breast cancer had a higher frequency of BRCA1 mutations than those with non-triple-negative breast cancer. In this study, no significant associations between the BRCA1/2 mutation status and age, family history of breast cancer, ovarian cancer, pancreatic cancer and prostate cancer, number of primary lesions, tumor size, or lymph node metastasis were observed.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Taxa de Mutação , Neoplasias de Mama Triplo Negativas/genética , Adulto , Idoso , China , Feminino , Síndrome Hereditária de Câncer de Mama e Ovário/epidemiologia , Humanos , Pessoa de Meia-Idade , Prevalência , Neoplasias de Mama Triplo Negativas/epidemiologia
19.
Oncogene ; 38(26): 5250-5264, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30894683

RESUMO

As a transcription factor critical for embryonic and adult stem cell self-renewal and function, SOX2 gene amplification has been recognized as a driving factor for various cancers including esophageal cancer. SOX2 overexpression occurs more broadly in cancer than gene amplification, but the mechanism is poorly understood. Here we showed that in esophageal cancer cell lines the levels of SOX2 proteins are not directly correlated to the copy numbers of SOX2 genes and are strongly influenced by proteostasis. We showed that AKT is a major determinant for SOX2 overexpression and does so by protecting SOX2 from ubiquitin-dependent protein degradation. We identified UBR5 as a major ubiquitin E3 ligase that induces SOX2 degradation through ubiquitinating SOX2 at lysine 115. Phosphorylation of SOX2 at threonine 116 by AKT inhibits the interaction of UBR5 with SOX2 and thus stabilizes SOX2. We provided evidence that AKT inhibitor can effectively downregulate SOX2 and suppress esopheageal cancer cell proliferation and stemness. Taken together, our study provides new insight into the mechanism of SOX2 overexpression in cancer and evidence for targeting AKT as a potential therapeutic strategy for SOX2-positive cancers.


Assuntos
Neoplasias Esofágicas/patologia , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Amplificação de Genes , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Células-Tronco Neoplásicas/metabolismo , Proteólise , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Regulação para Cima/genética
20.
Medicine (Baltimore) ; 98(7): e14479, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30762770

RESUMO

INTRODUCTION: Poststroke depression is a serious and common complication of stroke, especially the ischemic poststroke depression. Antidepressants are used in poststroke depression, and acupuncture may be an alternative approach. However, the efficacy and mechanism of acupuncture for poststroke depression has not been confirmed. METHODS/DESIGN: This is a multicenter, central-randomized, single-blind, sham-controlled clinical trial. We will allocate 208 subjects aged between 40 and 80 years old, diagnosed with initial poststroke depression (PSD) within 6 months to 2 groups randomly in a ratio of 1:1. Patients in the experimental group will be treated with traditional acupuncture and placebo pills, whereas the others in the control group will be treated with sham-acupoints acupuncture and antidepressant (fluoxetine hydrochloride tablets). All will be given acupuncture and/or medication treatment for 12 weeks, and then received 12-week follow-up. Patients will be evaluated with the 17-item Hamilton Depression Scale and Se1f-rating Depression Scale for depression state, National Institute of Health Stroke Scale for neurological deficit, Modified Barthel Index for activities of daily living, Treatment Emergent Symptom Scale for side effects of treatments, diagnosis and evaluation criteria of traditional Chinese medicine for stroke (try out) for curative effects of stroke, and clinical global impression for synthesize effect before and the 2nd, 4th, 8th, and 12th week of treatment, 24th week of follow-up. Study on mechanisms of acupuncture will be revealed through the diversity of brain metabolites (choline-containing compounds [Cho], N-acetylaspartate [NAA], myoinositol, glutamine and glutamate complex, creatine [Cr], Cho/Cr, Cho/NAA, Cr/NAA) in bilateral dorsolateral prefrontal cortex and anterior cingulate cortex monitored by proton magnetic resonance spectroscopy, and serum monoamine neurotransmitters (5-hydroxytryptamine, norepinephrine, dopamine) and cytokines (brain-derived neurotrophic factor [BDNF], interleukin [IL]-4, IL-6, IL-10, IL-18, IL-1ß, tumor necrosis factor alpha) before and the 12th week of treatment. Baseline characteristics of patients will be summarized by groups and compared with chi-square for categorical variables, and 2-sample t tests or Wilcoxon rank-sum test for the continuous variables. Primary and secondary outcomes according to the measurement times are applicable to univariate repetitive measurement deviation analysis or 2-sample t tests, or Wilcoxon rank-sum test. CONCLUSION: The present research is designed to investigate efficacy and mechanism of traditional acupuncture therapy on ischemic PSD, also to explore the correlation between cerebra metabolic and serologic factors, and ischemic PSD. With this research, we are looking forward to find out an appropriate alternative nondrug therapy for PSD people to alleviate the adverse effects and drug dependence caused by antidepressants.


Assuntos
Terapia por Acupuntura/métodos , Depressão/etiologia , Depressão/terapia , Projetos de Pesquisa , Acidente Vascular Cerebral/complicações , Atividades Cotidianas , Adulto , Idoso , Antidepressivos/uso terapêutico , Encéfalo/patologia , Citocinas/biossíntese , Depressão/tratamento farmacológico , Feminino , Fluoxetina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Neurotransmissores/biossíntese , Escalas de Graduação Psiquiátrica , Método Simples-Cego
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