Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
J Hazard Mater ; 469: 133932, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38484659

RESUMO

The extensive use of aluminum (Al) poses an escalating ecological risk to aquatic ecosystems. The epiphytic biofilm on submerged plant leaves plays a crucial role in the regulation nutrient cycling and energy flow within aquatic environments. Here, we conducted a mesocosm experiment aimed at elucidating the impact of different Al concentrations (0, 0.6, 1.2, 2.0 mg/L) on microbial communities in epiphytic biofilms on Vallisneria natans. At 1.2 mg/L, the highest biofilms thickness (101.94 µm) was observed. Al treatment at 2.0 mg/L significantly reduced bacterial diversity, while micro-eukaryotic diversity increased. Pseudomonadota and Bacteroidota decreased, whereas Cyanobacteriota increased at 1.2 mg/L and 2.0 mg/L. At 1.2 and 2.0 mg/L. Furthermore, Al at concentrations of 1.2 and 2.0 mg/L enhanced the bacterial network complexity, while micro-eukaryotic networks showed reduced complexity. An increase in positive correlations among microbial co-occurrence patterns from 49.51% (CK) to 57.05% (2.0 mg/L) was indicative of augmented microbial cooperation under Al stress. The shift in keystone taxa with increasing Al concentration pointed to alterations in the functional dynamics of microbial communities. Additionally, Al treatments induced antioxidant responses in V. natans, elevating leaf reactive oxygen species (ROS) content. This study highlights the critical need to control appropriate concentration Al concentrations to preserve microbial diversity, sustain ecological functions, and enhance lake remediation in aquatic ecosystems.


Assuntos
Hydrocharitaceae , Microbiota , Alumínio/toxicidade , Biofilmes , Folhas de Planta , Interações Microbianas
2.
Br J Ophthalmol ; 108(2): 285-293, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-36596662

RESUMO

BACKGROUND: The visual outcome of open globe injury (OGI)-no light perception (NLP) eyes is unpredictable traditionally. This study aimed to develop a model to predict the visual outcomes of vitrectomy surgery in OGI-NLP eyes using a machine learning algorithm and to provide an interpretable system for the prediction results. METHODS: Clinical data of 459 OGI-NLP eyes were retrospectively collected from 19 medical centres across China to establish a training data set for developing a model, called 'VisionGo', which can predict the visual outcome of the patients involved and compare with the Ocular Trauma Score (OTS). Another 72 cases were retrospectively collected and used for human-machine comparison, and an additional 27 cases were prospectively collected for real-world validation of the model. The SHapley Additive exPlanations method was applied to analyse feature contribution to the model. An online platform was built for real-world application. RESULTS: The area under the receiver operating characteristic curve (AUC) of VisionGo was 0.75 and 0.90 in previtrectomy and intravitrectomy application scenarios, which was much higher than the OTS (AUC=0.49). VisionGo showed better performance than ophthalmologists in both previtrectomy and intravitrectomy application scenarios (AUC=0.73 vs 0.57 and 0.87 vs 0.64). In real-world validation, VisionGo achieved an AUC of 0.60 and 0.91 in previtrectomy and intravitrectomy application scenarios. Feature contribution analysis indicated that wound length-related indicators, vitreous status and retina-related indicators contributed highly to visual outcomes. CONCLUSIONS: VisionGo has achieved an accurate and reliable prediction in visual outcome after vitrectomy for OGI-NLP eyes.


Assuntos
Ferimentos Oculares Penetrantes , Traumatismos Oculares , Humanos , Estudos Retrospectivos , Acuidade Visual , Retina , Vitrectomia , Prognóstico , Ferimentos Oculares Penetrantes/diagnóstico , Ferimentos Oculares Penetrantes/cirurgia
3.
Redox Biol ; 58: 102541, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36413918

RESUMO

Retinal ganglion cell (RGC) death is a hallmark of traumatic optic neuropathy, glaucoma, and other optic neuropathies that result in irreversible vision loss. However, therapeutic strategies for rescuing RGC loss still remain challenging, and the molecular mechanism underlying RGC loss has not been fully elucidated. Here, we highlight the role of ferroptosis, a non-apoptotic form of programmed cell death characterized by iron-dependent lethal lipid peroxides accumulation, in RGC death using an experimental model of glaucoma and optic nerve crush (ONC). ONC treatment resulted in significant downregulation of glutathione peroxidase 4 (GPx4) and system xc(-) cystine/glutamate antiporter (xCT) in the rat retina, accompanied by increased lipid peroxide and iron levels. The reduction of GPx4 expression in RGCs after ONC was confirmed by laser-capture microdissection and PCR. Transmission electron microscopy (TEM) revealed alterations in mitochondrial morphology, including increased membrane density and reduced mitochondrial cristae in RGCs after ONC. Notably, the ferroptosis inhibitor ferrostatin-1 (Fer-1) significantly promoted RGC survival and preserved retinal function in ONC and microbead-induced glaucoma mouse models. In addition, compared to the apoptosis inhibitor Z-VAD-FMK, Fer-1 showed better effect in rescuing RGCs death in ONC retinas. Mechanistically, we found the downregulation of GPx4 mainly occurred in the mitochondrial compartment, accompanied by increased mitochondrial reactive oxygen species (ROS) and lipid peroxides. The mitochondria-selective antioxidant MitoTEMPO attenuated RGC loss after ONC, implicating mitochondrial ROS and lipid peroxides as major mechanisms in ferroptosis-induced RGC death in ONC retinas. Notably, administering Fer-1 effectively prevented the production of mitochondrial lipid peroxides, the impairment of mitochondrial adenosine 5'-triphosphate (ATP) production, and the downregulation of mitochondrial genes, such as mt-Cytb and MT-ATP6, in ONC retinas. Our findings suggest that ferroptosis is a major form of regulated cell death for RGCs in experimental glaucoma and ONC models and suggesting targeting mitochondria-dependent ferroptosis as a protective strategy for RGC injuries in optic neuropathies.


Assuntos
Ferroptose , Glaucoma , Traumatismos do Nervo Óptico , Camundongos , Ratos , Animais , Células Ganglionares da Retina/metabolismo , Sobrevivência Celular , Peróxidos Lipídicos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismos do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/metabolismo , Modelos Animais de Doenças , Retina/metabolismo , Glaucoma/tratamento farmacológico , Glaucoma/genética , Ferro/metabolismo
4.
Front Immunol ; 13: 960094, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389744

RESUMO

The pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed serious threats to global health and economy and calls for the development of safe treatments and effective vaccines. The receptor-binding domain in the spike protein (SRBD) of SARS-CoV-2 is responsible for its binding to angiotensin-converting enzyme 2 (ACE2) receptor. It contains multiple dominant neutralizing epitopes and serves as an important antigen for the development of COVID-19 vaccines. Here, we showed that dimeric SRBD-Fc and tetrameric 2xSRBD-Fc fusion proteins bind ACE2 with different affinity and block SARS-CoV-2 pseudoviral infection. Immunization of mice with SRBD-Fc fusion proteins elicited high titer of RBD-specific antibodies with robust neutralizing activity against pseudoviral infections. As such, our study indicates that the polymeric SRBD-Fc fusion protein can serve as a treatment agent as well as a vaccine for fighting COVID-19.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Humanos , Camundongos , Animais , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Proteínas do Envelope Viral , Vacinas contra COVID-19 , Glicoproteínas de Membrana/metabolismo
5.
Invest Ophthalmol Vis Sci ; 63(6): 16, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35713893

RESUMO

Purpose: The purpose of this study was to investigate the effects of lysozyme, an antimicrobial enzyme found in tears that protects the eye against pathogens, on pseudotyped severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through corneal epithelial cells. Methods: The expression of the angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease (TMPRSS2) in human corneal epithelial cells (HCECs) was measured by RT-PCR and Western blotting. The altered expression of the pro-inflammatory molecules induced by spike protein and lysozyme was analyzed by RT-PCR. Cell toxicity was tested by CCK8 assay. The cell entry of SAR-CoV-2 in HCECs and primary rabbit corneal epithelial cells (RbCECs) was detected by luciferase assay. Results: ACE2 and TMPRSS2 were highly expressed in HCECs. The spike proteins of SARS-CoV-2 stimulated a robust inflammatory response in HCECs, characterized by increased secretion of pro-inflammatory molecules, including IL-6, TNF-α, iNOS, and MCP-1, and pretreatment with lysozyme in HCECs markedly decreased the production of proinflammatory molecules induced by spike proteins. In addition, the inflammatory cytokine TNF-α enhanced the entry of SARS-CoV-2 into HCECs, which can be mitigated by pretreatment with lysozyme. Conclusions: In this study, we analyzed the susceptibility of human corneal epithelial cells to SARS-CoV-2 infection and suggested the protective effects of lysozyme on SARS-CoV-2 infection.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Animais , Antivirais , Células Epiteliais/metabolismo , Humanos , Inflamação/metabolismo , Muramidase/metabolismo , Peptidil Dipeptidase A , Coelhos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563395

RESUMO

Recently developed Prime Editor 3 (PE3) has been implemented to induce genome editing in various cell types but has not been proven in human hematopoietic stem and progenitor cells. Using PE3, we successfully installed the beta-thalassemia (beta-thal) mutations in the HBB gene in the erythroid progenitor cell line HUDEP-2. We inserted the mCherry reporter gene cassette into editing plasmids, each including the prime editing guide RNA (pegRNA) and nick sgRNA. The plasmids were electroporated into HUDEP-2 cells, and the PE3 modified cells were identified by mCherry expression and collected using fluorescence-activated cell sorting (FACS). Sanger sequencing of the positive cells confirmed that PE3 induced precise beta-thal mutations with editing ratios from 4.55 to 100%. Furthermore, an off-target analysis showed no unintentional edits occurred in the cells. The editing ratios and parameters of pegRNA and nick sgRNA were also analyzed and summarized and will contribute to enhanced PE3 design in future studies. The characterization of the HUDEP-2 beta-thal cells showed typical thalassemia phenotypes, involving ineffective erythropoiesis, abnormal erythroid differentiation, high apoptosis rate, defective alpha-globin colocalization, cell viability deterioration, and ROS resisting deficiency. These HUDEP-2 beta-thal cells could provide ideal models for future beta-thal gene therapy studies.


Assuntos
Células Precursoras Eritroides , Edição de Genes , Hemoglobinas , Talassemia beta , Células Precursoras Eritroides/metabolismo , Edição de Genes/métodos , Hemoglobinas/genética , Hemoglobinas/uso terapêutico , Humanos , Mutação , alfa-Globinas/genética , Globinas beta/genética , Talassemia beta/genética , Talassemia beta/terapia
7.
Int J Mol Sci ; 23(5)2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35269949

RESUMO

ß-thalassemia is a hematologic disease that may be associated with significant morbidity and mortality. Increased expression of HBG1/2 can ameliorate the severity of ß-thalassemia. Compared to the unaffected population, some ß-thalassemia patients display elevated HBG1/2 expression levels in their red blood cells. However, the magnitude of up-regulation does not reach the threshold of self-healing, and thus, the molecular mechanism underlying HBG1/2 expression in the context of HBB-deficiency requires further elucidation. Here, we performed a multi-omics study examining chromatin accessibility, transcriptome, proteome, and phosphorylation patterns in the HBB homozygous knockout of the HUDEP2 cell line (HBB-KO). We found that up-regulation of HBG1/2 in HBB-KO cells was not induced by the H3K4me3-mediated genetic compensation response. Deletion of HBB in human erythroid progenitor cells resulted in increased ROS levels and production of oxidative stress, which led to an increased rate of apoptosis. Furthermore, in response to oxidative stress, slower cell cycle progression and proliferation were observed. In addition, stress erythropoiesis was initiated leading to increased intracellular HBG1/2 expression. This molecular model was also validated in the single-cell transcriptome of hematopoietic stem cells from ß-hemoglobinopathy patients. These findings further the understanding of HBG1/2 gene regulatory networks and provide novel clinical insights into ß-thalassemia phenotypic diversity.


Assuntos
Talassemia beta , Contagem de Eritrócitos , Eritrócitos/metabolismo , Células Precursoras Eritroides/metabolismo , Eritropoese/genética , Humanos
8.
Gene ; 820: 146289, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35143940

RESUMO

Reactivation of fetal hemoglobin by editing the B-cell lymphoma/leukemia 11A (BCL11A) erythroid enhancer is an effective gene therapy for ß-thalassemia. Using the CRISPR/Cas9 system, fetal γ-globin expression can be robustly reactivated to mitigate the clinical course of ß-thalassemia. In our study, we found that the transfection efficiencies of CD34+ hematopoietic stem/progenitor cells (HSPCs) were significantly and negatively correlated with the length of plasmids and greatly affected by the linearization of plasmids. Furthermore, the transgene expression of minicircles (MC) without plasmid backbone sequences was better both in vitro and in vivo compared with conventional plasmids. Thus, MC DNA was used to deliver the cassette of Staphylococcus aureus Cas9 (SaCas9) into HSPCs, and a single-guide RNA targeting the erythroid enhancer region of BCL11A was selected. After electroporation with MC DNA, an evident efficiency of gene editing and reactivation of γ-globin expression in erythroblasts derived from unsorted HSPCs was acquired. No significant off-target effects were found by deep sequencing. Furthermore, fragments derived from lentiviral vectors, but not MC DNA, were highly enriched in promoter, exon, intron, distal-intergenic, and cancer-associated genes, indicating that MC DNA provided a relatively safe and efficient vector for delivering transgenes. The developed MC DNA vector provided a potential approach for the delivery of SaCas9 cassette and the reactivation of γ-globin expression for ameliorating syndromes of ß-thalassemia.


Assuntos
DNA Circular/uso terapêutico , Hemoglobina Fetal/metabolismo , Proteínas Repressoras/metabolismo , Talassemia beta/genética , Talassemia beta/terapia , gama-Globinas/genética , gama-Globinas/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas , DNA Circular/metabolismo , Edição de Genes , Terapia Genética/métodos , Vetores Genéticos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasmídeos , Regiões Promotoras Genéticas , RNA Guia de Cinetoplastídeos/metabolismo , RNA Guia de Cinetoplastídeos/uso terapêutico
9.
Photodiagnosis Photodyn Ther ; 36: 102481, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34403826

RESUMO

BACKGROUND: To explore the association of cigarette smoking with retinal thickness and vascular structure in an elderly Chinese population. METHODS: This cross-sectional study enrolled employees and retirees aged over 50 years at Tianjin University of Sport from October 2020 to December 2020. Information on smoking status and lifestyle was obtained using a detailed questionnaire. All participants underwent full ophthalmic examination. OCTA image was acquired. Vascular and the thickness parameters in central fovea and peripapillary parameters were automatically calculated. Multiple linear regression analyses were utilized to assess the association of smoking with retinal thickness and vascular structure after controlling potential confounders. RESULTS: Compared with non-smoking adults, current smokers (ß=-36.78; P = 0.01) and ever smokers (ß=-35.45; P = 0.00) tended to have thinner macular fovea. Cigarettes daily, pack-years of smoking and CSI were negatively related to macular thickness (cigarettes daily: ß=-1.43; pack-years: ß=-14.73; CSI: ß=-14.70), while they were positively associated with the circumference (cigarettes daily: ß=0.03; pack-years: ß=0.30; CSI: ß=0.31) and the area of FAZ (cigarettes daily: ß=0.01; pack-years: ß=0.07). CONCLUSIONS: Cigarette smoking seems associated with decreased macular fovea thickness and elevated circumference and area of the FAZ compared to non-smokers. Our data add to evidence of smoking on retinal thickness and the microvascular system in the macular area.


Assuntos
Fumar Cigarros , Fotoquimioterapia , Adulto , Idoso , China/epidemiologia , Estudos Transversais , Angiofluoresceinografia , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica
10.
Biomed Res Int ; 2021: 5512624, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124242

RESUMO

Prostate cancer is currently associated with higher morbidity and mortality in men in the United States and Western Europe, so it is important to identify genes that regulate prostate cancer. The high-dimension gene expression profile impedes the discovery of biclusters which are of great significance to the identification of the basic cellular processes controlled by multiple genes and the identification of large-scale unknown effects hidden in the data. We applied the biclustering method MCbiclust to explore large biclusters in the TCGA cohort through a large number of iterations. Two biclusters were found with the highest silhouette coefficient value. The expression patterns of one bicluster are highly similar to those found by the gene expression profile of the known androgen-regulated genes. Further gene set enrichment revealed that mitochondrial function-related genes were negatively correlated with AR regulation-related genes. Then, we performed differential analysis, AR binding site analysis, and survival analysis on the core genes with high phenotypic contribution. Among the core genes, NDUFA10 showed a low expression value in cancer patients across different expression profiles, while NDUFV2 showed a high expression value in cancer patients. Survival analysis of NDUFA10 and NDUFV2 demonstrated that both genes were unfavorable prognostic markers.


Assuntos
Biomarcadores Tumorais , Bases de Dados de Ácidos Nucleicos , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas Mitocondriais , NADH Desidrogenase , Proteínas de Neoplasias , Neoplasias da Próstata , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Intervalo Livre de Doença , Perfilação da Expressão Gênica , Humanos , Masculino , Proteínas Mitocondriais/biossíntese , Proteínas Mitocondriais/genética , NADH Desidrogenase/biossíntese , NADH Desidrogenase/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/mortalidade , Taxa de Sobrevida
11.
Front Oncol ; 11: 656675, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33987091

RESUMO

Single-cell RNA sequencing is a powerful tool to explore the heterogeneity of breast cancer. The identification of the cell subtype that responds to estrogen has profound significance in breast cancer research and treatment. The transcriptional regulation of estrogen is an intricate network involving crosstalk between protein-coding and non-coding RNAs, which is still largely unknown, particularly at the single cell level. Therefore, we proposed a novel strategy to specify cell subtypes based on a cell-specific ceRNA network (CCN). The CCN was constructed by integrating a cell-specific RNA-RNA co-expression network (RCN) with an existing ceRNA network. The cell-specific RCN was built based on single cell expression profiles with predefined reference cells. Heterogeneous cell subtypes were inferred by enriching RNAs in CCN to the estrogen response hallmark. Edge biomarkers were identified in the early estrogen response subtype. Topological analysis revealed that NEAT1 was a hub lncRNA for the early response subtype, and its ceRNAs could predict patient survival. Another hub lncRNA, DLEU2, could potentially be involved in GPCR signaling, based on CCN. The CCN method that we proposed here facilitates the inference of cell subtypes from a network perspective and explores the function of hub lncRNAs, which are promising targets for RNA-based therapeutics.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA