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1.
World J Surg Oncol ; 22(1): 156, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38872167

RESUMEN

BACKGROUND: Non-small cell lung cancer (NSCLC) is a prevalent and heterogeneous disease with significant genomic variations between the early and advanced stages. The identification of key genes and pathways driving NSCLC tumor progression is critical for improving the diagnosis and treatment outcomes of this disease. METHODS: In this study, we conducted single-cell transcriptome analysis on 93,406 cells from 22 NSCLC patients to characterize malignant NSCLC cancer cells. Utilizing cNMF, we classified these cells into distinct modules, thus identifying the diverse molecular profiles within NSCLC. Through pseudotime analysis, we delineated temporal gene expression changes during NSCLC evolution, thus demonstrating genes associated with disease progression. Using the XGBoost model, we assessed the significance of these genes in the pseudotime trajectory. Our findings were validated by using transcriptome sequencing data from The Cancer Genome Atlas (TCGA), supplemented via LASSO regression to refine the selection of characteristic genes. Subsequently, we established a risk score model based on these genes, thus providing a potential tool for cancer risk assessment and personalized treatment strategies. RESULTS: We used cNMF to classify malignant NSCLC cells into three functional modules, including the metabolic reprogramming module, cell cycle module, and cell stemness module, which can be used for the functional classification of malignant tumor cells in NSCLC. These findings also indicate that metabolism, the cell cycle, and tumor stemness play important driving roles in the malignant evolution of NSCLC. We integrated cNMF and XGBoost to select marker genes that are indicative of both early and advanced NSCLC stages. The expression of genes such as CHCHD2, GAPDH, and CD24 was strongly correlated with the malignant evolution of NSCLC at the single-cell data level. These genes have been validated via histological data. The risk score model that we established (represented by eight genes) was ultimately validated with GEO data. CONCLUSION: In summary, our study contributes to the identification of temporal heterogeneous biomarkers in NSCLC, thus offering insights into disease progression mechanisms and potential therapeutic targets. The developed workflow demonstrates promise for future applications in clinical practice.


Asunto(s)
Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Aprendizaje Automático , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Pronóstico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Progresión de la Enfermedad , Femenino , Masculino , Transcriptoma , Análisis de la Célula Individual/métodos
2.
Comput Biol Med ; 175: 108532, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703547

RESUMEN

BACKGROUND: Glioma is a malignant brain tumor originating from glial cells, and there still a challenge to accurately predict the prognosis. Programmed cell death (PCD) plays a key role in tumorigenesis and immune response. However, the crosstalk and potential role of various PCDs in prognosis and tumor microenvironment remains unknown. Therefore, we comprehensively discussed the relationship between different models of PCD and the prognosis of glioma and provided new ideas for the optimal targeted therapy of glioma. MATERIALS AND METHODS: We compared and analyzed the role of 14 PCD patterns on the prognosis from different levels. We constructed the cell death risk score (CDRS) index and conducted a comprehensive analysis of CDRS and TME characteristics, clinical characteristics, and drug response. RESULTS: Effects of different PCDs at the genomic, functional, and immune microenvironment levels were discussed. CDRS index containing 6 gene signatures and a nomogram were established. High CDRS is associated with a worse prognosis. Through transcriptome and single-cell data, we found that patients with high CDRS showed stronger immunosuppressive characteristics. Moreover, the high-CDRS group was resistant to the traditional glioma chemotherapy drug Vincristine, but more sensitive to the Temozolomide and the clinical experimental drug Bortezomib. In addition, we identified 19 key potential therapeutic targets during malignant differentiation of tumor cells. CONCLUSION: Overall, we provide the first systematic description of the role of 14 PCDs in glioma. A new CDRS model was built to predict the prognosis and to provide a new idea for the targeted therapy of glioma.


Asunto(s)
Neoplasias Encefálicas , Glioma , Microambiente Tumoral , Humanos , Glioma/genética , Glioma/tratamiento farmacológico , Glioma/inmunología , Glioma/patología , Glioma/mortalidad , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/patología , Pronóstico , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Resistencia a Antineoplásicos , Transcriptoma , Apoptosis/efectos de los fármacos
3.
Respir Res ; 25(1): 126, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491375

RESUMEN

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive disease with a five-year survival rate of less than 40%. There is significant variability in survival time among IPF patients, but the underlying mechanisms for this are not clear yet. METHODS AND RESULTS: We collected single-cell RNA sequence data of 13,223 epithelial cells taken from 32 IPF patients and bulk RNA sequence data from 456 IPF patients in GEO. Based on unsupervised clustering analysis at the single-cell level and deconvolution algorithm at bulk RNA sequence data, we discovered a special alveolar type 2 cell subtype characterized by high expression of CCL20 (referred to as ATII-CCL20), and found that IPF patients with a higher proportion of ATII-CCL20 had worse prognoses. Furthermore, we uncovered the upregulation of immune cell infiltration and metabolic functions in IPF patients with a higher proportion of ATII-CCL20. Finally, the comprehensive decision tree and nomogram were constructed to optimize the risk stratification of IPF patients and provide a reference for accurate prognosis evaluation. CONCLUSIONS: Our study by integrating single-cell and bulk RNA sequence data from IPF patients identified a special subtype of ATII cells, ATII-CCL20, which was found to be a risk cell subtype associated with poor prognosis in IPF patients. More importantly, the ATII-CCL20 cell subtype was linked with metabolic functions and immune infiltration.


Asunto(s)
Fibrosis Pulmonar Idiopática , Humanos , Fibrosis Pulmonar Idiopática/diagnóstico , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/metabolismo , Células Epiteliales Alveolares/metabolismo , Células Epiteliales/metabolismo , Perfilación de la Expresión Génica , Pronóstico , Transcriptoma
4.
Database (Oxford) ; 20242024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38242684

RESUMEN

The phenotypes of drug action, including therapeutic actions and adverse drug reactions (ADRs), are important indicators for evaluating the druggability of new drugs and repositioning the approved drugs. Here, we provide a user-friendly database, DAPredict (http://bio-bigdata.hrbmu.edu.cn/DAPredict), in which our novel original drug action phenotypes prediction algorithm (Yang,J., Zhang,D., Liu,L. et al. (2021) Computational drug repositioning based on the relationships between substructure-indication. Brief. Bioinformatics, 22, bbaa348) was embedded. Our algorithm integrates characteristics of chemical genomics and pharmacogenomics, breaking through the limitations that traditional drug development process based on phenotype cannot analyze the mechanism of drug action. Predicting phenotypes of drug action based on the local active structures of drugs and proteins can achieve more innovative drug discovery across drug categories and simultaneously evaluate drug efficacy and safety, rather than traditional one-by-one evaluation. DAPredict contains 305 981 predicted relationships between 1748 approved drugs and 454 ADRs, 83 117 predicted relationships between 1478 approved drugs and 178 Anatomical Therapeutic Chemicals (ATC). More importantly, DAPredict provides an online prediction tool, which researchers can use to predict the action phenotypic spectrum of more than 110 000 000 compounds (including about 168 000 natural products) and corresponding proteins to analyze their potential effect mechanisms. DAPredict can also help researchers obtain the phenotype-corresponding active structures for structural optimization of new drug candidates, making it easier to evaluate the druggability of new drug candidates and develop more innovative drugs across drug categories. Database URL:  http://bio-bigdata.hrbmu.edu.cn/DAPredict/.


Asunto(s)
Algoritmos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Biología Computacional , Genómica , Bases de Datos Factuales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/genética , Fenotipo , Reposicionamiento de Medicamentos
5.
Sci Total Environ ; 877: 162923, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36933735

RESUMEN

Rampant use of antibiotics has caused a rapid dissemination of antibiotic resistance genes (ARGs) in environment, posing great threats to ecosystems and human health. Applying biochar (BC) in natural systems to combat the spread of ARGs arises as an attention-grabbing solution. Unfortunately, the effectiveness of BC is still unmanageable due to the incomprehensive knowledge over correlations between BC properties and extracellular ARGs transformation. To pinpoint the crucial factors, we primarily explored transformation behaviors of plasmid-mediated ARGs exposed to BC (in suspensions or extraction solutions), adsorption capacities of ARGs on BC, and growth inhibition of E. coli imposed by BC. Specifically, the effects of BC properties including particle size (large-particulate 150 µm and colloidal 0.45-2 µm) and pyrolytic temperature (300, 400, 500, 600, and 700 °C) on the ARGs transformation were emphasized. Results showed that both large-particulate BC and colloidal BC, irrespective of their pyrolytic temperature, would induce significant inhibitory effects on the ARGs transformation, while the BC extraction solutions showed little effect except BC pyrolyzed at 300 °C. Correlation analysis uncovered that the inhibition effect of BC on ARGs transformation was tightly correlated with its adsorption capacity towards plasmid. Accordingly, greater inhibitory effects from those BCs with higher pyrolytic temperatures and smaller particle sizes mainly originated from their greater adsorption capacities. Intriguingly, E. coli was unable to ingest the plasmid adsorbed on BC, which led to ARGs blocked outside the cell membrane, although this inhibitory effect was partially affected by survival inhibition of BC on E. coli. Particularly, significant plasmid aggregation could occur in the extraction solution of large-particulate BC pyrolyzed at 300 °C, leading to a significant inhibition of ARGs transformation. Overall, our findings complete the insufficient understanding over the effects of BC on ARGs transformation behavior, and potentially provide new insights to scientific communities in mitigating ARGs spreading.


Asunto(s)
Antibacterianos , Ecosistema , Humanos , Antibacterianos/farmacología , Temperatura , Tamaño de la Partícula , Escherichia coli/genética , Carbón Orgánico , Farmacorresistencia Microbiana/genética , Genes Bacterianos
6.
Cancers (Basel) ; 14(19)2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36230722

RESUMEN

At present, most patients with oral squamous cell carcinoma (OSCC) are in the middle or advanced stages at the time of diagnosis. Advanced OSCC patients have a poor prognosis after traditional therapy, and the complex heterogeneity of OSCC has been proven to be one of the main reasons. Single-cell sequencing technology provides a powerful tool for dissecting the heterogeneity of cancer. However, most of the current studies at the single-cell level are static, while the development of cancer is a dynamic process. Thus, understanding the development of cancer from a dynamic perspective and formulating corresponding therapeutic measures for achieving precise treatment are highly necessary, and this is also one of the main study directions in the field of oncology. In this study, we combined the static and dynamic analysis methods based on single-cell RNA-Seq data to comprehensively dissect the complex heterogeneity and evolutionary process of OSCC. Subsequently, for clinical practice, we revealed the association between cancer heterogeneity and the prognosis of patients. More importantly, we pioneered the concept of pseudo-time score of patients, and we quantified the levels of heterogeneity based on the dynamic development process to evaluate the relationship between the score and the survival status at the same stage, finding that it is closely related to the prognostic status. The pseudo-time score of patients could not only reflect the tumor status of patients but also be used as an indicator of the effects of drugs on the patients so that the medication strategy can be adjusted on time. Finally, we identified candidate drugs and proposed precision medication strategies to control the condition of OSCC in two respects: treatment and blocking.

7.
Oxid Med Cell Longev ; 2022: 3472179, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105485

RESUMEN

The accumulation of multiple genetic mutations is essential during the occurrence and development of hepatocellular carcinoma induced by hepatitis B (HBV-HCC), but understanding their cooperative effects and identifying the warning transition point from hepatitis B to HCC are challenges. In the genomic analysis of somatic mutations of the patient with HBV-HCC in a patient-specific protein-protein interaction (ps-PPI) network, we find mutation influence can propagate along the ps-PPI network. Therefore, in the article, we got the mutation cluster as a new research unit using the Random Walks with Restarts algorithm that is used to describe the efficient boundary of mutation influences. The connection of mutation cluster leads to dysregulation of signaling pathways corresponding to HCC, while dysregulated signaling pathways accumulate gradually and experience a process from quantitative to qualitative changes including a critical mutation cluster called transition point (TP) from hepatitis B to HCC. Moreover, two subtypes of HCC patients with different prognosis and their corresponding biological and clinical characteristics were identified according to TP. The poor prognosis HCC subtype was associated with significant metabolic pathway dysregulation and lower immune cell infiltration, while we also identified several preventive drugs to block the transformation of hepatitis B to hepatocellular carcinoma. The network-level study integrated multiomics data not only showed the sequence of multiple somatic mutations and their cooperative effect but also identified the warning transition point in HCC tumorigenesis for each patient. Our study provides new insight into exploring the cooperative molecular mechanism of chronic inflammatory malignancy in the liver and lays the foundation for the development of new approaches for early prediction and diagnosis of hepatocellular carcinoma and personalized targeted therapy.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Diagnóstico Precoz , Hepatitis B/complicaciones , Hepatitis B/tratamiento farmacológico , Hepatitis B/genética , Virus de la Hepatitis B/genética , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Acumulación de Mutaciones
8.
J Hazard Mater ; 423(Pt B): 127150, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-34530277

RESUMEN

The rapid spread of antibiotic resistance genes (ARGs) has posed a risk to human health. Here, the effects of biochar (BC) on the horizontal transfer of ARG-carrying plasmids to Escherichia coli via transformation were systematically investigated. BC could significantly inhibit the transformation of ARGs and the inhibition degree increased with pyrolysis temperature. Rice straw-derived BC showed a stronger inhibitory effect on the transformation of ARGs than that of peanut shell-derived BC from the same pyrolysis temperature. The inhibitory effect of BC from low pyrolysis temperature (300 â„ƒ) was mainly caused by BC dissolutions, while it was mainly attributed to BC solids for high pyrolysis temperature (700 â„ƒ) BC. BC dissolutions could induce intramolecular condensation and even agglomeration of plasmids, hindering their transformation into competent bacteria. The cell membrane permeability was slightly decreased in BC dissolutions, which might also contribute to the inhibitory effect. Plasmid can be adsorbed by BC solids and the adsorption increased with BC pyrolysis temperature. Meanwhile, BC-adsorbed plasmid could hardly be transformed into E. coli. BC solids could also deactivate E. coli and thereby inhibit their uptake of ARGs. These findings provide a way using BC to limit the spread of ARGs in the environment.


Asunto(s)
Antibacterianos , Escherichia coli , Antibacterianos/farmacología , Carbón Orgánico , Farmacorresistencia Microbiana/genética , Escherichia coli/genética , Genes Bacterianos , Humanos , Plásmidos/genética
9.
BMC Cancer ; 21(1): 918, 2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34388989

RESUMEN

BACKGROUND: Breast cancer (BC) is a complex disease with high heterogeneity, which often leads to great differences in treatment results. Current common molecular typing method is PAM50, which shows positive results for precision medicine; however, room for improvement still remains because of the different prognoses of subtypes. Therefore, in this article, we used lncRNAs, which are more tissue-specific and developmental stage-specific than other RNAs, as typing markers and combined single-cell expression profiles to retype BC, to provide a new method for BC classification and explore new precise therapeutic strategies based on this method. METHODS: Based on lncRNA expression profiles of 317 single cells from 11 BC patients, SC3 was used to retype BC, and differential expression analysis and enrichment analysis were performed to identify biological characteristics of new subtypes. The results were validated for survival analysis using data from TCGA. Then, the downstream regulatory genes of lncRNA markers of each subtype were searched by expression correlation analysis, and these genes were used as targets to screen therapeutic drugs, thus proposing new precision treatment strategies according to the different subtype compositions of patients. RESULTS: Seven lncRNA subtypes and their specific biological characteristics are obtained. Then, 57 targets and 210 drugs of 7 subtypes were acquired. New precision medicine strategies were proposed according to the different compositions of patient subtypes. CONCLUSIONS: For patients with different subtype compositions, we propose a strategy to select different drugs for different patients, which means using drugs targeting multi subtype or combinations of drugs targeting a single subtype to simultaneously kill different cancer cells by personalized treatment, thus reducing the possibility of drug resistance and even recurrence.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama/genética , Heterogeneidad Genética , ARN Largo no Codificante/genética , Análisis de la Célula Individual , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Toma de Decisiones Clínicas , Biología Computacional/métodos , Manejo de la Enfermedad , Femenino , Perfilación de la Expresión Génica/métodos , Predisposición Genética a la Enfermedad , Humanos , Medicina de Precisión/métodos , Pronóstico , Análisis de la Célula Individual/métodos
10.
Future Med Chem ; 13(15): 1271-1283, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34137272

RESUMEN

Background: A comprehensive approach to drug repositioning will be required to overcome translational hurdles and identify more neuroprotective drugs. Results & methods: Gene Set Enrichment Analysis was applied to identify related pathways and enriched genes. Candidate genes were optimized using ToppGene, ToppGenet and pBRIT. From the perspective of the local structures, gene-domain-substructure-drug relationships were constructed. Using the MCODE algorithm and K-means clustering, 31 functional subnetworks were obtained, and 252 drugs with proposed neuroprotective function were identified. Using computational analysis, 72 substructures with different scores were found to correspond to neuroprotective functions. The protective effects of benidipine and barnidipine were confirmed in vitro. Conclusion: The authors' research has great potential to discover more neuroprotective drugs and obtain more information regarding mechanisms of action and functional substructures.


Asunto(s)
Biología Computacional/métodos , Reposicionamiento de Medicamentos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Algoritmos , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Dihidropiridinas/química , Dihidropiridinas/farmacología , Dihidropiridinas/uso terapéutico , Descubrimiento de Drogas , Humanos , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/patología , Ratones , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Nifedipino/análogos & derivados , Nifedipino/química , Nifedipino/farmacología , Nifedipino/uso terapéutico , Estrés Oxidativo/efectos de los fármacos
11.
J Cancer Res Clin Oncol ; 147(7): 1881-1895, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33693962

RESUMEN

INTRODUCTION: Glioblastoma (GBM) is a complex disease with high intratumoral heterogeneity, understanding the molecular characteristics of intratumoral heterogeneity accurately is the basis for precision treatment. Although the existing typing strategy based on tumor molecular characteristics has a positive effect, there is still room for improvement, which is mainly because the traditional typing is completed based on the sequencing data of tissue samples, that is, the obtained data are the average level of patient tumor tissues, masking the intratumoral heterogeneity of a single patient and cannot reflect the real level of patient tumor cells. At present, cancer molecular typing is mostly performed based on transcriptome (RNA-seq) without considering lncRNA molecules that are also tissue-specific and developmental stage-specific. Therefore, in this study, we used lncRNAs as typing markers and combined single-cell expression profiles to retype glioblastoma, providing new ideas for GBM molecular typing, and further analyzed the shortcomings of traditional therapies at the singlecell level based on typing results and proposed new precise therapeutic insights. METHODS: We downloaded GBM single-cell sequencing data from GSE84465 and performed a series of preprocessing. The intratumoral heterogeneity of patients at the single-cell level was revealed using t-SNE, and the room for improvement of the existing traditional histotyping method was revealed using heat map and density curve. Subsequently, to validate the feasibility of lncRNA typing, we compared the similarities and differences of expression patterns between lncRNAs and mRNAs in GBM cells. Then, we used the R package "Seurat" to perform unsupervised clustering of GBM cells for re-typing and performed a detailed analysis of the biological characteristics of each subtype, including differentially expressed lncRNAs and marker lncRNAs. For validation, we performed survival analysis on GBM tissue data from the TCGA database to reveal the impact of different subtypes on patient survival prognosis. Eventually, based on the results, we screened the therapeutic drugs of each subtype by targeting the downstream regulatory genes of lncRNAs and proposed a new precision therapeutic strategy. RESULTS: GBM has significant intratumoral heterogeneity at the single-cell level, with more than one traditional subtype highly expressed in each patient, which reflects the shortcomings of traditional histotyping. LncRNAs and mRNAs have similar expression patterns in GBM cells, and the expression coefficient of variation of lncRNAs is higher than that of mRNAs, meaning that lncRNAs will better reflect the intratumoral heterogeneity. GBM was reclassified into four subtypes by unsupervised clustering, with different subtypes having different biological characteristics. Survival analysis showed that patients with different subtype compositions had different prognostic outcomes, so different subtypes had different effects on patient prognosis. Based on this, 47 drugs were screened for treatment. There are both shared and unique drugs between different subtypes. A new precision treatment strategy was proposed: for patients with different subtypes, in addition to the combination of drugs targeting single subtype, drugs targeting multiple subtypes can also be selected. CONCLUSION: Intratumoral heterogeneity may lead to poor prognosis or recurrence after treatment, and more precise typing of GBM can be performed based on single-cell lncRNA expression profiles. The biological characteristics possessed by different subtypes will have different effects on patients, such as survival time. For different subtypes, there are both drugs targeting single subtype and drugs targeting multiple subtypes, and we prefer drugs targeting multiple subtypes because this strategy can maximize medication efficiency and reduce the types of medication to reduce risks and side effects.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Glioblastoma/genética , Medicina de Precisión , ARN Largo no Codificante/genética , Análisis de la Célula Individual/métodos , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Glioblastoma/patología , Glioblastoma/terapia , Humanos , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia
12.
J Environ Sci (China) ; 101: 205-216, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33334516

RESUMEN

With increasing environmental application, biochar (BC) will inevitably interact with and impact environmental behaviors of widely distributed extracellular DNA (eDNA), which however still remains to be studied. Herein, the adsorption/desorption and the degradation by nucleases of eDNA on three aromatized BCs pyrolyzed at 700 °C were firstly investigated. The results show that the eDNA was irreversibly adsorbed by aromatized BCs and the pseudo-second-order and Freundlich models accurately described the adsorption process. Increasing solution ionic strength or decreasing pH below 5.0 significantly increased the eDNA adsorption on BCs. However, increasing pH from 5.0 to 10.0 faintly decreased eDNA adsorption. Electrostatic interaction, Ca ion bridge interaction, and π-π interaction between eDNA and BC could dominate the eDNA adsorption, while ligand exchange and hydrophobic interactions were minor contributors. The presence of BCs provided a certain protection to eDNA against degradation by DNase I. BC-bound eDNA could be partly degraded by nuclease, while BC-bound nuclease completely lost its degradability. These findings are of fundamental significance for the potential application of biochar in eDNA dissemination management and evaluating the environmental fate of eDNA.


Asunto(s)
Carbón Orgánico , Desoxirribonucleasa I , Adsorción , ADN , Cinética
13.
J Environ Sci (China) ; 100: 269-278, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33279039

RESUMEN

The release of biochar colloids considerably affects the stability of biochar in environment. Currently, information on the release behavior and suspension stability of biochar colloids in real soil solutions is scarce. In this study, 20 soils were collected from different districts in China and the release behavior of biochar colloids and their suspension stability in soil solutions were systematically examined. The results showed that both pyrolysis temperature and biomass source had important effects on the formation of biochar colloids in soil solutions. The formation amount of biochar colloids from low pyrolysis temperatures (400 °C) (average amount of 9.33-16.41 mg/g) were significantly higher than those from high pyrolysis temperatures (700 °C) (average amount of less than 2 mg/g). The formation amount of wheat straw-derived biochar colloids were higher than those of rice straw-derived biochar colloids probably due to the higher O/C ratio in wheat-straw biochar. Further, biochar colloidal formation amount was negatively correlated with comprehensive effect of dissolved organic carbon, Fe and Al in soil solutions. The sedimentation curve of biochar colloids in soil solutions is well described by an exponential model and demonstrated high suspension stability. Around 40% of the biochar colloids were maintained in the suspension at the final sedimentation equilibrium. The settling efficiency of biochar colloids was positively correlated with comprehensive effect of the ionic strength and K, Ca, Na, and Mg contents in soil solutions. Our findings help promote a deeper understanding of biochar loss and stability in the soil-water environment.


Asunto(s)
Carbón Orgánico , Suelo , China , Coloides , Soluciones
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